| Message ID | 1494156804-9784-1-git-send-email-rajmohan.mani@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Rajmohan, Thanks for the patch! A quick code review: On 05/07/2017 01:33 PM, rajmohan.mani@intel.com wrote: > From: Rajmohan Mani <rajmohan.mani@intel.com> > > DW9714 is a 10 bit DAC, designed for linear > control of voice coil motor. > > This driver creates a V4L2 subdevice and > provides control to set the desired focus. > > Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com> > --- > drivers/media/i2c/Kconfig | 9 ++ > drivers/media/i2c/Makefile | 1 + > drivers/media/i2c/dw9714.c | 333 +++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 343 insertions(+) > create mode 100644 drivers/media/i2c/dw9714.c > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > index fd181c9..4f0a7ad 100644 > --- a/drivers/media/i2c/Kconfig > +++ b/drivers/media/i2c/Kconfig > @@ -300,6 +300,15 @@ config VIDEO_AD5820 > This is a driver for the AD5820 camera lens voice coil. > It is used for example in Nokia N900 (RX-51). > > +config VIDEO_DW9714 > + tristate "DW9714 lens voice coil support" > + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER > + ---help--- > + This is a driver for the DW9714 camera lens voice coil. > + DW9714 is a 10 bit DAC with 120mA output current sink > + capability. This is designed for linear control of > + voice coil motors, controlled via I2C serial interface. > + > config VIDEO_SAA7110 > tristate "Philips SAA7110 video decoder" > depends on VIDEO_V4L2 && I2C > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > index 62323ec..987bd1f 100644 > --- a/drivers/media/i2c/Makefile > +++ b/drivers/media/i2c/Makefile > @@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_SAA7127) += saa7127.o > obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o > obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o > obj-$(CONFIG_VIDEO_AD5820) += ad5820.o > +obj-$(CONFIG_VIDEO_DW9714) += dw9714.o > obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o > obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o > obj-$(CONFIG_VIDEO_ADV7180) += adv7180.o > diff --git a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c > new file mode 100644 > index 0000000..276d3f2 > --- /dev/null > +++ b/drivers/media/i2c/dw9714.c > @@ -0,0 +1,333 @@ > +/* > + * Copyright (c) 2015--2017 Intel Corporation. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License version > + * 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/acpi.h> > +#include <linux/delay.h> > +#include <linux/i2c.h> > +#include <linux/module.h> > +#include <linux/pm_runtime.h> > +#include <media/v4l2-ctrls.h> > +#include <media/v4l2-device.h> > + > +#define DW9714_NAME "dw9714" > +#define DW9714_MAX_FOCUS_POS 1023 > +#define DW9714_CTRL_STEPS 16 /* Keep this value power of 2 */ > +#define DW9714_CTRL_DELAY_US 1000 > +/* > + * S[3:2] = 0x00, codes per step for "Linear Slope Control" > + * S[1:0] = 0x00, step period > + */ > +#define DW9714_DEFAULT_S 0x0 > +#define DW9714_VAL(data, s) (u16)((data) << 4 | (s)) > + > +/* dw9714 device structure */ > +struct dw9714_device { > + struct i2c_client *client; > + struct v4l2_ctrl_handler ctrls_vcm; > + struct v4l2_subdev sd; > + u16 current_val; > +}; > + > +#define to_dw9714_vcm(_ctrl) \ > + container_of(_ctrl->handler, struct dw9714_device, ctrls_vcm) > + > +static int dw9714_i2c_write(struct i2c_client *client, u16 data) > +{ > + const int num_msg = 1; > + int ret; > + u16 val = cpu_to_be16(data); > + struct i2c_msg msg = { > + .addr = client->addr, > + .flags = 0, > + .len = sizeof(val), > + .buf = (u8 *) &val, > + }; > + > + ret = i2c_transfer(client->adapter, &msg, num_msg); > + > + /*One retry */ > + if (ret != num_msg) > + ret = i2c_transfer(client->adapter, &msg, num_msg); > + > + if (ret != num_msg) { > + dev_err(&client->dev, "I2C write fail fail\n"); > + return -EIO; > + } else { No need for the 'else' here, since the 'if' already returns. > + return 0; > + } > +} > + > +static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val) > +{ > + struct i2c_client *client = dw9714_dev->client; > + int ret = -EINVAL; > + > + dev_dbg(&client->dev, "Setting new value VCM: %d\n", val); > + dw9714_dev->current_val = val; > + > + ret = dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S)); > + return ret; Just do return dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S)); Thus dropping the 'ret' variable. > +} > + > +static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl) > +{ > + struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl); > + > + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) > + return dw9714_t_focus_vcm(dev_vcm, ctrl->val); Personally I would merge the dw9714_t_focus_vcm in here. And probably use a switch instead of an if. Up to you, though. > + else No need for 'else' > + return -EINVAL; > +} > + > +static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = { > + .s_ctrl = dw9714_set_ctrl, > +}; > + > +static int dw9714_init_controls(struct dw9714_device *dev_vcm) > +{ > + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; > + const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops; > + struct i2c_client *client = dev_vcm->client; > + > + v4l2_ctrl_handler_init(hdl, 1); > + > + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, > + 0, DW9714_MAX_FOCUS_POS, 1, 0); > + > + if (hdl->error) > + dev_err(&client->dev, "dw9714_init_controls fail\n"); > + dev_vcm->sd.ctrl_handler = hdl; > + return hdl->error; > +} > + > +static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev) > +{ > + v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm); > + v4l2_async_unregister_subdev(&dw9714_dev->sd); > + v4l2_device_unregister_subdev(&dw9714_dev->sd); > + media_entity_cleanup(&dw9714_dev->sd.entity); > +} > + > +static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + struct device *dev = &dw9714_dev->client->dev; > + int rval; > + > + rval = pm_runtime_get_sync(dev); > + dev_dbg(dev, "%s rval = %d\n", __func__, rval); The error is propagated to userspace anyway as errno, so do you really need a dev_dbg here? > + > + return rval; > +} > + > +static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + struct device *dev = &dw9714_dev->client->dev; > + > + dev_dbg(dev, "%s\n", __func__); Seems useless here as well. > + pm_runtime_put(dev); > + > + return 0; > +} > + > +static const struct v4l2_subdev_internal_ops dw9714_int_ops = { > + .open = dw9714_open, > + .close = dw9714_close, > +}; > + > +static const struct v4l2_subdev_ops dw9714_ops = { }; > + > +static int dw9714_probe(struct i2c_client *client, > + const struct i2c_device_id *devid) > +{ > + struct dw9714_device *dw9714_dev; > + int rval; > + > + dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev), > + GFP_KERNEL); > + > + if (dw9714_dev == NULL) > + return -ENOMEM; > + > + dw9714_dev->client = client; > + > + v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); > + dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; > + dw9714_dev->sd.internal_ops = &dw9714_int_ops; > + > + snprintf(dw9714_dev->sd.name, > + sizeof(dw9714_dev->sd.name), > + DW9714_NAME " %d-%4.4x", i2c_adapter_id(client->adapter), > + client->addr); v4l2_i2c_subdev_init() already fills in the sd.name, so this can be dropped. > + > + rval = dw9714_init_controls(dw9714_dev); > + if (rval) > + goto err_cleanup; > + > + rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL); > + if (rval < 0) > + goto err_cleanup; > + > + dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS; > + > + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > + if (rval < 0) > + goto err_cleanup; > + > + pm_runtime_enable(&client->dev); > + > + return 0; > + > +err_cleanup: > + dw9714_subdev_cleanup(dw9714_dev); > + dev_err(&client->dev, "Probe failed: %d\n", rval); > + return rval; > +} > + > +static int dw9714_remove(struct i2c_client *client) > +{ > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + > + pm_runtime_disable(&client->dev); > + dw9714_subdev_cleanup(dw9714_dev); > + > + return 0; > +} > + > +#ifdef CONFIG_PM > + > +static int dw9714_runtime_suspend(struct device *dev) > +{ > + return 0; > +} > + > +static int dw9714_runtime_resume(struct device *dev) > +{ > + return 0; > +} > + > +/* This function sets the vcm position, so it consumes least current */ > +static int dw9714_suspend(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + int ret, val; > + > + dev_dbg(dev, "%s\n", __func__); > + > + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > + val >= 0; val -= DW9714_CTRL_STEPS) { > + ret = dw9714_i2c_write(client, > + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > + if (ret) > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > + } > + return 0; > +} > + > +/* > + * This function sets the vcm position, so the focus position is set > + * closer to the camera > + */ > +static int dw9714_resume(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + int ret, val; > + > + dev_dbg(dev, "%s\n", __func__); > + > + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > + val += DW9714_CTRL_STEPS) { > + ret = dw9714_i2c_write(client, > + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > + if (ret) > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > + } > + > + /* restore v4l2 control values */ > + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); > + dev_dbg(dev, "%s ret = %d\n", __func__, ret); > + return ret; > +} > + > +#else > + > +#define dw9714_suspend NULL > +#define dw9714_resume NULL > +#define dw9714_runtime_suspend NULL > +#define dw9714_runtime_resume NULL > + > +#endif /* CONFIG_PM */ > + > +#ifdef CONFIG_ACPI > +static const struct acpi_device_id dw9714_acpi_match[] = { > + {"DW9714", 0}, > + {}, > +}; > +MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match); > +#endif > + > +static const struct i2c_device_id dw9714_id_table[] = { > + {DW9714_NAME, 0}, > + {} > +}; > + > +MODULE_DEVICE_TABLE(i2c, dw9714_id_table); > + > +static const struct dev_pm_ops dw9714_pm_ops = { > + .suspend = dw9714_suspend, > + .resume = dw9714_resume, > + .runtime_suspend = dw9714_runtime_suspend, > + .runtime_resume = dw9714_runtime_resume, > +}; > + > +static struct i2c_driver dw9714_i2c_driver = { > + .driver = { > + .name = DW9714_NAME, > + .pm = &dw9714_pm_ops, > +#ifdef CONFIG_ACPI > + .acpi_match_table = ACPI_PTR(dw9714_acpi_match), > +#endif > + }, > + .probe = dw9714_probe, > + .remove = dw9714_remove, > + .id_table = dw9714_id_table, > +}; > + > +module_i2c_driver(dw9714_i2c_driver); > + > +MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); > +MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>"); > +MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>"); > +MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>"); > +MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>"); > +MODULE_DESCRIPTION("DW9714 VCM driver"); > +MODULE_LICENSE("GPL"); > Regards, Hans
Hi Hans, Thanks for the quick review. Please see my comments inline... I will post the new v2 patch soon. > -----Original Message----- > From: Hans Verkuil [mailto:hverkuil@xs4all.nl] > Sent: Monday, May 08, 2017 6:59 PM > To: Mani, Rajmohan <rajmohan.mani@intel.com>; linux- > media@vger.kernel.org; mchehab@kernel.org > Subject: Re: [PATCH] dw9714: Initial driver for dw9714 VCM > > Hi Rajmohan, > > Thanks for the patch! > > A quick code review: > > On 05/07/2017 01:33 PM, rajmohan.mani@intel.com wrote: > > From: Rajmohan Mani <rajmohan.mani@intel.com> > > > > DW9714 is a 10 bit DAC, designed for linear control of voice coil > > motor. > > > > This driver creates a V4L2 subdevice and provides control to set the > > desired focus. > > > > Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com> > > --- > > drivers/media/i2c/Kconfig | 9 ++ > > drivers/media/i2c/Makefile | 1 + > > drivers/media/i2c/dw9714.c | 333 > > +++++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 343 insertions(+) > > create mode 100644 drivers/media/i2c/dw9714.c > > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > > index fd181c9..4f0a7ad 100644 > > --- a/drivers/media/i2c/Kconfig > > +++ b/drivers/media/i2c/Kconfig > > @@ -300,6 +300,15 @@ config VIDEO_AD5820 > > This is a driver for the AD5820 camera lens voice coil. > > It is used for example in Nokia N900 (RX-51). > > > > +config VIDEO_DW9714 > > + tristate "DW9714 lens voice coil support" > > + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER > > + ---help--- > > + This is a driver for the DW9714 camera lens voice coil. > > + DW9714 is a 10 bit DAC with 120mA output current sink > > + capability. This is designed for linear control of > > + voice coil motors, controlled via I2C serial interface. > > + > > config VIDEO_SAA7110 > > tristate "Philips SAA7110 video decoder" > > depends on VIDEO_V4L2 && I2C > > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > > index 62323ec..987bd1f 100644 > > --- a/drivers/media/i2c/Makefile > > +++ b/drivers/media/i2c/Makefile > > @@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_SAA7127) += saa7127.o > > obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o > > obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o > > obj-$(CONFIG_VIDEO_AD5820) += ad5820.o > > +obj-$(CONFIG_VIDEO_DW9714) += dw9714.o > > obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o > > obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o > > obj-$(CONFIG_VIDEO_ADV7180) += adv7180.o diff --git > > a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c new file > > mode 100644 index 0000000..276d3f2 > > --- /dev/null > > +++ b/drivers/media/i2c/dw9714.c > > @@ -0,0 +1,333 @@ > > +/* > > + * Copyright (c) 2015--2017 Intel Corporation. > > + * > > + * This program is free software; you can redistribute it and/or > > + * modify it under the terms of the GNU General Public License > > +version > > + * 2 as published by the Free Software Foundation. > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + */ > > + > > +#include <linux/acpi.h> > > +#include <linux/delay.h> > > +#include <linux/i2c.h> > > +#include <linux/module.h> > > +#include <linux/pm_runtime.h> > > +#include <media/v4l2-ctrls.h> > > +#include <media/v4l2-device.h> > > + > > +#define DW9714_NAME "dw9714" > > +#define DW9714_MAX_FOCUS_POS 1023 > > +#define DW9714_CTRL_STEPS 16 /* Keep this value power of 2 > */ > > +#define DW9714_CTRL_DELAY_US 1000 > > +/* > > + * S[3:2] = 0x00, codes per step for "Linear Slope Control" > > + * S[1:0] = 0x00, step period > > + */ > > +#define DW9714_DEFAULT_S 0x0 > > +#define DW9714_VAL(data, s) (u16)((data) << 4 | (s)) > > + > > +/* dw9714 device structure */ > > +struct dw9714_device { > > + struct i2c_client *client; > > + struct v4l2_ctrl_handler ctrls_vcm; > > + struct v4l2_subdev sd; > > + u16 current_val; > > +}; > > + > > +#define to_dw9714_vcm(_ctrl) \ > > + container_of(_ctrl->handler, struct dw9714_device, ctrls_vcm) > > + > > +static int dw9714_i2c_write(struct i2c_client *client, u16 data) { > > + const int num_msg = 1; > > + int ret; > > + u16 val = cpu_to_be16(data); > > + struct i2c_msg msg = { > > + .addr = client->addr, > > + .flags = 0, > > + .len = sizeof(val), > > + .buf = (u8 *) &val, > > + }; > > + > > + ret = i2c_transfer(client->adapter, &msg, num_msg); > > + > > + /*One retry */ > > + if (ret != num_msg) > > + ret = i2c_transfer(client->adapter, &msg, num_msg); > > + > > + if (ret != num_msg) { > > + dev_err(&client->dev, "I2C write fail fail\n"); > > + return -EIO; > > + } else { > > No need for the 'else' here, since the 'if' already returns. Ack I also removed the redundant " fail" in the dev_err() message. > > > + return 0; > > + } > > +} > > + > > +static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 > > +val) { > > + struct i2c_client *client = dw9714_dev->client; > > + int ret = -EINVAL; > > + > > + dev_dbg(&client->dev, "Setting new value VCM: %d\n", val); > > + dw9714_dev->current_val = val; > > + > > + ret = dw9714_i2c_write(client, DW9714_VAL(val, > DW9714_DEFAULT_S)); > > + return ret; > > Just do return dw9714_i2c_write(client, DW9714_VAL(val, > DW9714_DEFAULT_S)); > > Thus dropping the 'ret' variable. Ack > > > +} > > + > > +static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl) { > > + struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl); > > + > > + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) > > + return dw9714_t_focus_vcm(dev_vcm, ctrl->val); > > Personally I would merge the dw9714_t_focus_vcm in here. And probably use a > switch instead of an if. Up to you, though. With just one ctrl->id, dw9714_set_ctrl() looks to be more readable with the if and dw9714_t_focus_vcm() call. When more ids are added, merging of dw9714_t_focus_vcm() and switch statement becomes more apt. So, for now, I am leaving it as such. > > > + else > > No need for 'else' Ack > > > + return -EINVAL; > > +} > > + > > +static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = { > > + .s_ctrl = dw9714_set_ctrl, > > +}; > > + > > +static int dw9714_init_controls(struct dw9714_device *dev_vcm) { > > + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; > > + const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops; > > + struct i2c_client *client = dev_vcm->client; > > + > > + v4l2_ctrl_handler_init(hdl, 1); > > + > > + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, > > + 0, DW9714_MAX_FOCUS_POS, 1, 0); > > + > > + if (hdl->error) > > + dev_err(&client->dev, "dw9714_init_controls fail\n"); > > + dev_vcm->sd.ctrl_handler = hdl; > > + return hdl->error; > > +} > > + > > +static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev) { > > + v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm); > > + v4l2_async_unregister_subdev(&dw9714_dev->sd); > > + v4l2_device_unregister_subdev(&dw9714_dev->sd); > > + media_entity_cleanup(&dw9714_dev->sd.entity); > > +} > > + > > +static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh > > +*fh) { > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + struct device *dev = &dw9714_dev->client->dev; > > + int rval; > > + > > + rval = pm_runtime_get_sync(dev); > > + dev_dbg(dev, "%s rval = %d\n", __func__, rval); > > The error is propagated to userspace anyway as errno, so do you really need a > dev_dbg here? Ack I removed the dev_dbg message. I also got rid of rval, by just doing ret pm_runtime_get_sync(dev) > > > + > > + return rval; > > +} > > + > > +static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh > > +*fh) { > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + struct device *dev = &dw9714_dev->client->dev; > > + > > + dev_dbg(dev, "%s\n", __func__); > > Seems useless here as well. Ack > > > + pm_runtime_put(dev); > > + > > + return 0; > > +} > > + > > +static const struct v4l2_subdev_internal_ops dw9714_int_ops = { > > + .open = dw9714_open, > > + .close = dw9714_close, > > +}; > > + > > +static const struct v4l2_subdev_ops dw9714_ops = { }; > > + > > +static int dw9714_probe(struct i2c_client *client, > > + const struct i2c_device_id *devid) { > > + struct dw9714_device *dw9714_dev; > > + int rval; > > + > > + dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev), > > + GFP_KERNEL); > > + > > + if (dw9714_dev == NULL) > > + return -ENOMEM; > > + > > + dw9714_dev->client = client; > > + > > + v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); > > + dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; > > + dw9714_dev->sd.internal_ops = &dw9714_int_ops; > > + > > + snprintf(dw9714_dev->sd.name, > > + sizeof(dw9714_dev->sd.name), > > + DW9714_NAME " %d-%4.4x", i2c_adapter_id(client- > >adapter), > > + client->addr); > > v4l2_i2c_subdev_init() already fills in the sd.name, so this can be dropped. Ack > > > + > > + rval = dw9714_init_controls(dw9714_dev); > > + if (rval) > > + goto err_cleanup; > > + > > + rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL); > > + if (rval < 0) > > + goto err_cleanup; > > + > > + dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS; > > + > > + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > > + if (rval < 0) > > + goto err_cleanup; > > + > > + pm_runtime_enable(&client->dev); > > + > > + return 0; > > + > > +err_cleanup: > > + dw9714_subdev_cleanup(dw9714_dev); > > + dev_err(&client->dev, "Probe failed: %d\n", rval); > > + return rval; > > +} > > + > > +static int dw9714_remove(struct i2c_client *client) { > > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + > > + pm_runtime_disable(&client->dev); > > + dw9714_subdev_cleanup(dw9714_dev); > > + > > + return 0; > > +} > > + > > +#ifdef CONFIG_PM > > + > > +static int dw9714_runtime_suspend(struct device *dev) { > > + return 0; > > +} > > + > > +static int dw9714_runtime_resume(struct device *dev) { > > + return 0; > > +} > > + > > +/* This function sets the vcm position, so it consumes least current > > +*/ static int dw9714_suspend(struct device *dev) { > > + struct i2c_client *client = to_i2c_client(dev); > > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + int ret, val; > > + > > + dev_dbg(dev, "%s\n", __func__); > > + > > + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > > + val >= 0; val -= DW9714_CTRL_STEPS) { > > + ret = dw9714_i2c_write(client, > > + DW9714_VAL((u16) val, > DW9714_DEFAULT_S)); > > + if (ret) > > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > > + usleep_range(DW9714_CTRL_DELAY_US, > DW9714_CTRL_DELAY_US + 10); > > + } > > + return 0; > > +} > > + > > +/* > > + * This function sets the vcm position, so the focus position is set > > + * closer to the camera > > + */ > > +static int dw9714_resume(struct device *dev) { > > + struct i2c_client *client = to_i2c_client(dev); > > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + int ret, val; > > + > > + dev_dbg(dev, "%s\n", __func__); > > + > > + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > > + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > > + val += DW9714_CTRL_STEPS) { > > + ret = dw9714_i2c_write(client, > > + DW9714_VAL((u16) val, > DW9714_DEFAULT_S)); > > + if (ret) > > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > > + usleep_range(DW9714_CTRL_DELAY_US, > DW9714_CTRL_DELAY_US + 10); > > + } > > + > > + /* restore v4l2 control values */ > > + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); > > + dev_dbg(dev, "%s ret = %d\n", __func__, ret); > > + return ret; > > +} > > + > > +#else > > + > > +#define dw9714_suspend NULL > > +#define dw9714_resume NULL > > +#define dw9714_runtime_suspend NULL > > +#define dw9714_runtime_resume NULL > > + > > +#endif /* CONFIG_PM */ > > + > > +#ifdef CONFIG_ACPI > > +static const struct acpi_device_id dw9714_acpi_match[] = { > > + {"DW9714", 0}, > > + {}, > > +}; > > +MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match); #endif > > + > > +static const struct i2c_device_id dw9714_id_table[] = { > > + {DW9714_NAME, 0}, > > + {} > > +}; > > + > > +MODULE_DEVICE_TABLE(i2c, dw9714_id_table); > > + > > +static const struct dev_pm_ops dw9714_pm_ops = { > > + .suspend = dw9714_suspend, > > + .resume = dw9714_resume, > > + .runtime_suspend = dw9714_runtime_suspend, > > + .runtime_resume = dw9714_runtime_resume, }; > > + > > +static struct i2c_driver dw9714_i2c_driver = { > > + .driver = { > > + .name = DW9714_NAME, > > + .pm = &dw9714_pm_ops, > > +#ifdef CONFIG_ACPI > > + .acpi_match_table = ACPI_PTR(dw9714_acpi_match), #endif > > + }, > > + .probe = dw9714_probe, > > + .remove = dw9714_remove, > > + .id_table = dw9714_id_table, > > +}; > > + > > +module_i2c_driver(dw9714_i2c_driver); > > + > > +MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); > > +MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>"); > > +MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>"); > > +MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>"); > > +MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>"); > > +MODULE_DESCRIPTION("DW9714 VCM driver"); MODULE_LICENSE("GPL"); > > > > Regards, > > Hans
Hi Rajmohan, A few comments below... On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: > From: Rajmohan Mani <rajmohan.mani@intel.com> > > DW9714 is a 10 bit DAC, designed for linear > control of voice coil motor. > > This driver creates a V4L2 subdevice and > provides control to set the desired focus. > > Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com> > --- > drivers/media/i2c/Kconfig | 9 ++ > drivers/media/i2c/Makefile | 1 + > drivers/media/i2c/dw9714.c | 333 +++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 343 insertions(+) > create mode 100644 drivers/media/i2c/dw9714.c > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > index fd181c9..4f0a7ad 100644 > --- a/drivers/media/i2c/Kconfig > +++ b/drivers/media/i2c/Kconfig > @@ -300,6 +300,15 @@ config VIDEO_AD5820 > This is a driver for the AD5820 camera lens voice coil. > It is used for example in Nokia N900 (RX-51). > > +config VIDEO_DW9714 > + tristate "DW9714 lens voice coil support" > + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER You should also depend on VIDEO_V4L2_SUBDEV_API . > + ---help--- > + This is a driver for the DW9714 camera lens voice coil. > + DW9714 is a 10 bit DAC with 120mA output current sink > + capability. This is designed for linear control of > + voice coil motors, controlled via I2C serial interface. > + > config VIDEO_SAA7110 > tristate "Philips SAA7110 video decoder" > depends on VIDEO_V4L2 && I2C > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > index 62323ec..987bd1f 100644 > --- a/drivers/media/i2c/Makefile > +++ b/drivers/media/i2c/Makefile > @@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_SAA7127) += saa7127.o > obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o > obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o > obj-$(CONFIG_VIDEO_AD5820) += ad5820.o > +obj-$(CONFIG_VIDEO_DW9714) += dw9714.o > obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o > obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o > obj-$(CONFIG_VIDEO_ADV7180) += adv7180.o > diff --git a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c > new file mode 100644 > index 0000000..276d3f2 > --- /dev/null > +++ b/drivers/media/i2c/dw9714.c > @@ -0,0 +1,333 @@ > +/* > + * Copyright (c) 2015--2017 Intel Corporation. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License version > + * 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include <linux/acpi.h> > +#include <linux/delay.h> > +#include <linux/i2c.h> > +#include <linux/module.h> > +#include <linux/pm_runtime.h> > +#include <media/v4l2-ctrls.h> > +#include <media/v4l2-device.h> > + > +#define DW9714_NAME "dw9714" > +#define DW9714_MAX_FOCUS_POS 1023 > +#define DW9714_CTRL_STEPS 16 /* Keep this value power of 2 */ > +#define DW9714_CTRL_DELAY_US 1000 > +/* > + * S[3:2] = 0x00, codes per step for "Linear Slope Control" > + * S[1:0] = 0x00, step period > + */ > +#define DW9714_DEFAULT_S 0x0 > +#define DW9714_VAL(data, s) (u16)((data) << 4 | (s)) > + > +/* dw9714 device structure */ > +struct dw9714_device { > + struct i2c_client *client; > + struct v4l2_ctrl_handler ctrls_vcm; > + struct v4l2_subdev sd; > + u16 current_val; > +}; > + > +#define to_dw9714_vcm(_ctrl) \ > + container_of(_ctrl->handler, struct dw9714_device, ctrls_vcm) > + > +static int dw9714_i2c_write(struct i2c_client *client, u16 data) > +{ > + const int num_msg = 1; > + int ret; > + u16 val = cpu_to_be16(data); > + struct i2c_msg msg = { > + .addr = client->addr, > + .flags = 0, > + .len = sizeof(val), > + .buf = (u8 *) &val, > + }; > + > + ret = i2c_transfer(client->adapter, &msg, num_msg); > + > + /*One retry */ > + if (ret != num_msg) > + ret = i2c_transfer(client->adapter, &msg, num_msg); > + > + if (ret != num_msg) { > + dev_err(&client->dev, "I2C write fail fail\n"); > + return -EIO; > + } else { > + return 0; > + } > +} > + > +static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val) > +{ > + struct i2c_client *client = dw9714_dev->client; > + int ret = -EINVAL; > + > + dev_dbg(&client->dev, "Setting new value VCM: %d\n", val); > + dw9714_dev->current_val = val; > + > + ret = dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S)); > + return ret; > +} > + > +static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl) > +{ > + struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl); > + > + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) > + return dw9714_t_focus_vcm(dev_vcm, ctrl->val); > + else > + return -EINVAL; > +} > + > +static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = { > + .s_ctrl = dw9714_set_ctrl, > +}; > + > +static int dw9714_init_controls(struct dw9714_device *dev_vcm) > +{ > + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; > + const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops; > + struct i2c_client *client = dev_vcm->client; > + > + v4l2_ctrl_handler_init(hdl, 1); > + > + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, > + 0, DW9714_MAX_FOCUS_POS, 1, 0); > + > + if (hdl->error) > + dev_err(&client->dev, "dw9714_init_controls fail\n"); > + dev_vcm->sd.ctrl_handler = hdl; > + return hdl->error; > +} > + > +static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev) > +{ > + v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm); Please release the control handler after unregistering the sub-device. > + v4l2_async_unregister_subdev(&dw9714_dev->sd); > + v4l2_device_unregister_subdev(&dw9714_dev->sd); > + media_entity_cleanup(&dw9714_dev->sd.entity); > +} > + > +static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + struct device *dev = &dw9714_dev->client->dev; > + int rval; > + > + rval = pm_runtime_get_sync(dev); If this fails you'll need to do pm_runtime_put(dev); > + dev_dbg(dev, "%s rval = %d\n", __func__, rval); > + > + return rval; > +} > + > +static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + struct device *dev = &dw9714_dev->client->dev; > + > + dev_dbg(dev, "%s\n", __func__); > + pm_runtime_put(dev); > + > + return 0; > +} > + > +static const struct v4l2_subdev_internal_ops dw9714_int_ops = { > + .open = dw9714_open, > + .close = dw9714_close, > +}; > + > +static const struct v4l2_subdev_ops dw9714_ops = { }; You should use v4l2_subdev_internal_ops here. > + > +static int dw9714_probe(struct i2c_client *client, > + const struct i2c_device_id *devid) > +{ > + struct dw9714_device *dw9714_dev; > + int rval; > + > + dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev), > + GFP_KERNEL); > + > + if (dw9714_dev == NULL) > + return -ENOMEM; > + > + dw9714_dev->client = client; > + > + v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); > + dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; > + dw9714_dev->sd.internal_ops = &dw9714_int_ops; > + > + snprintf(dw9714_dev->sd.name, > + sizeof(dw9714_dev->sd.name), > + DW9714_NAME " %d-%4.4x", i2c_adapter_id(client->adapter), > + client->addr); > + > + rval = dw9714_init_controls(dw9714_dev); > + if (rval) > + goto err_cleanup; > + > + rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL); > + if (rval < 0) > + goto err_cleanup; > + > + dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS; > + > + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > + if (rval < 0) > + goto err_cleanup; > + > + pm_runtime_enable(&client->dev); Getting PM runtime right doesn't seem to be easy. :-I pm_runtime_enable() alone doesn't do the trick. I wonder if adding pm_runtime_suspend() would do the trick. > + > + return 0; > + > +err_cleanup: > + dw9714_subdev_cleanup(dw9714_dev); > + dev_err(&client->dev, "Probe failed: %d\n", rval); > + return rval; > +} > + > +static int dw9714_remove(struct i2c_client *client) > +{ > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + > + pm_runtime_disable(&client->dev); > + dw9714_subdev_cleanup(dw9714_dev); > + > + return 0; > +} > + > +#ifdef CONFIG_PM > + > +static int dw9714_runtime_suspend(struct device *dev) > +{ > + return 0; > +} > + > +static int dw9714_runtime_resume(struct device *dev) > +{ > + return 0; I think it'd be fine to remove empty callbacks. > +} > + > +/* This function sets the vcm position, so it consumes least current */ > +static int dw9714_suspend(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + int ret, val; > + > + dev_dbg(dev, "%s\n", __func__); > + > + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > + val >= 0; val -= DW9714_CTRL_STEPS) { > + ret = dw9714_i2c_write(client, > + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > + if (ret) > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > + } > + return 0; > +} > + > +/* > + * This function sets the vcm position, so the focus position is set > + * closer to the camera > + */ > +static int dw9714_resume(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + int ret, val; > + > + dev_dbg(dev, "%s\n", __func__); > + > + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > + val += DW9714_CTRL_STEPS) { > + ret = dw9714_i2c_write(client, > + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > + if (ret) > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > + } > + > + /* restore v4l2 control values */ > + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); Doesn't this need to be done for runtime_resume as well? > + dev_dbg(dev, "%s ret = %d\n", __func__, ret); > + return ret; > +} > + > +#else > + > +#define dw9714_suspend NULL > +#define dw9714_resume NULL > +#define dw9714_runtime_suspend NULL > +#define dw9714_runtime_resume NULL > + > +#endif /* CONFIG_PM */ > + > +#ifdef CONFIG_ACPI > +static const struct acpi_device_id dw9714_acpi_match[] = { > + {"DW9714", 0}, > + {}, > +}; > +MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match); > +#endif > + > +static const struct i2c_device_id dw9714_id_table[] = { > + {DW9714_NAME, 0}, > + {} > +}; > + > +MODULE_DEVICE_TABLE(i2c, dw9714_id_table); > + > +static const struct dev_pm_ops dw9714_pm_ops = { > + .suspend = dw9714_suspend, > + .resume = dw9714_resume, > + .runtime_suspend = dw9714_runtime_suspend, > + .runtime_resume = dw9714_runtime_resume, > +}; > + > +static struct i2c_driver dw9714_i2c_driver = { > + .driver = { > + .name = DW9714_NAME, > + .pm = &dw9714_pm_ops, > +#ifdef CONFIG_ACPI > + .acpi_match_table = ACPI_PTR(dw9714_acpi_match), > +#endif > + }, > + .probe = dw9714_probe, > + .remove = dw9714_remove, > + .id_table = dw9714_id_table, > +}; > + > +module_i2c_driver(dw9714_i2c_driver); > + > +MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); > +MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>"); > +MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>"); > +MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>"); > +MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>"); > +MODULE_DESCRIPTION("DW9714 VCM driver"); > +MODULE_LICENSE("GPL");
Hi Sakari, On Tue, May 9, 2017 at 4:55 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote: > Hi Rajmohan, > > A few comments below... > > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: [snip] >> + rval = v4l2_async_register_subdev(&dw9714_dev->sd); >> + if (rval < 0) >> + goto err_cleanup; >> + >> + pm_runtime_enable(&client->dev); > > Getting PM runtime right doesn't seem to be easy. :-I > > pm_runtime_enable() alone doesn't do the trick. I wonder if adding > pm_runtime_suspend() would do the trick. Is this something specific for I2C devices? For platform devices, typically pm_runtime_enable() is the only thing you would need to do. > >> + >> + return 0; >> + >> +err_cleanup: >> + dw9714_subdev_cleanup(dw9714_dev); >> + dev_err(&client->dev, "Probe failed: %d\n", rval); >> + return rval; >> +} >> + >> +static int dw9714_remove(struct i2c_client *client) >> +{ >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> + struct dw9714_device *dw9714_dev = container_of(sd, >> + struct dw9714_device, >> + sd); >> + >> + pm_runtime_disable(&client->dev); >> + dw9714_subdev_cleanup(dw9714_dev); >> + >> + return 0; >> +} >> + >> +#ifdef CONFIG_PM >> + >> +static int dw9714_runtime_suspend(struct device *dev) >> +{ >> + return 0; >> +} >> + >> +static int dw9714_runtime_resume(struct device *dev) >> +{ >> + return 0; > > I think it'd be fine to remove empty callbacks. It's actually a bit more complicated (if a PM domain is attached, the callbacks must be present), however in case of external I2C devices it should be fine indeed. However, AFAIK, pm_runtime_no_callbacks() should be called. > >> +} >> + >> +/* This function sets the vcm position, so it consumes least current */ >> +static int dw9714_suspend(struct device *dev) >> +{ >> + struct i2c_client *client = to_i2c_client(dev); >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> + struct dw9714_device *dw9714_dev = container_of(sd, >> + struct dw9714_device, >> + sd); >> + int ret, val; >> + >> + dev_dbg(dev, "%s\n", __func__); >> + >> + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); >> + val >= 0; val -= DW9714_CTRL_STEPS) { >> + ret = dw9714_i2c_write(client, >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); >> + if (ret) >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); >> + } >> + return 0; >> +} >> + >> +/* >> + * This function sets the vcm position, so the focus position is set >> + * closer to the camera >> + */ >> +static int dw9714_resume(struct device *dev) >> +{ >> + struct i2c_client *client = to_i2c_client(dev); >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> + struct dw9714_device *dw9714_dev = container_of(sd, >> + struct dw9714_device, >> + sd); >> + int ret, val; >> + >> + dev_dbg(dev, "%s\n", __func__); >> + >> + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; >> + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; >> + val += DW9714_CTRL_STEPS) { >> + ret = dw9714_i2c_write(client, >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); >> + if (ret) >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); >> + } >> + >> + /* restore v4l2 control values */ >> + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); > > Doesn't this need to be done for runtime_resume as well? This driver doesn't seem to be doing any physical power off in its runtime_suspend and I don't expect an I2C device to be put in a PM domain, so possibly no need for it. Best regards, Tomasz
Hi Tomasz, On Tue, May 09, 2017 at 04:30:40PM +0800, Tomasz Figa wrote: > Hi Sakari, > > On Tue, May 9, 2017 at 4:55 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote: > > Hi Rajmohan, > > > > A few comments below... > > > > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: > [snip] > >> + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > >> + if (rval < 0) > >> + goto err_cleanup; > >> + > >> + pm_runtime_enable(&client->dev); > > > > Getting PM runtime right doesn't seem to be easy. :-I > > > > pm_runtime_enable() alone doesn't do the trick. I wonder if adding > > pm_runtime_suspend() would do the trick. > > Is this something specific for I2C devices? For platform devices, > typically pm_runtime_enable() is the only thing you would need to do. I think you're right --- driver_probe_device() will call pm_request_idle() to the device right after probe. So indeed calling pm_runtime_enable() is enough. > >> + > >> + return 0; > >> + > >> +err_cleanup: > >> + dw9714_subdev_cleanup(dw9714_dev); > >> + dev_err(&client->dev, "Probe failed: %d\n", rval); > >> + return rval; > >> +} > >> + > >> +static int dw9714_remove(struct i2c_client *client) > >> +{ > >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); > >> + struct dw9714_device *dw9714_dev = container_of(sd, > >> + struct dw9714_device, > >> + sd); > >> + > >> + pm_runtime_disable(&client->dev); > >> + dw9714_subdev_cleanup(dw9714_dev); > >> + > >> + return 0; > >> +} > >> + > >> +#ifdef CONFIG_PM > >> + > >> +static int dw9714_runtime_suspend(struct device *dev) > >> +{ > >> + return 0; > >> +} > >> + > >> +static int dw9714_runtime_resume(struct device *dev) > >> +{ > >> + return 0; > > > > I think it'd be fine to remove empty callbacks. > > It's actually a bit more complicated (if a PM domain is attached, the > callbacks must be present), however in case of external I2C devices it > should be fine indeed. However, AFAIK, pm_runtime_no_callbacks() > should be called. I wonder if I'm missing something --- acpi_subsys_runtime_resume() first calls acpi_dev_runtime_resume() and if all goes well, the proceeds to call pm_generic_runtime_resume() which calls device's runtime_resume() if it's non-NULL. In other words, having a runtime_resume() and runtime_suspend() callbacks that return zero is equivalent of having neither of the callbacks. > > > > >> +} > >> + > >> +/* This function sets the vcm position, so it consumes least current */ > >> +static int dw9714_suspend(struct device *dev) > >> +{ > >> + struct i2c_client *client = to_i2c_client(dev); > >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); > >> + struct dw9714_device *dw9714_dev = container_of(sd, > >> + struct dw9714_device, > >> + sd); > >> + int ret, val; > >> + > >> + dev_dbg(dev, "%s\n", __func__); > >> + > >> + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > >> + val >= 0; val -= DW9714_CTRL_STEPS) { > >> + ret = dw9714_i2c_write(client, > >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > >> + if (ret) > >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); > >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > >> + } > >> + return 0; > >> +} > >> + > >> +/* > >> + * This function sets the vcm position, so the focus position is set > >> + * closer to the camera > >> + */ > >> +static int dw9714_resume(struct device *dev) > >> +{ > >> + struct i2c_client *client = to_i2c_client(dev); > >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); > >> + struct dw9714_device *dw9714_dev = container_of(sd, > >> + struct dw9714_device, > >> + sd); > >> + int ret, val; > >> + > >> + dev_dbg(dev, "%s\n", __func__); > >> + > >> + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > >> + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > >> + val += DW9714_CTRL_STEPS) { > >> + ret = dw9714_i2c_write(client, > >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > >> + if (ret) > >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); > >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > >> + } > >> + > >> + /* restore v4l2 control values */ > >> + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); > > > > Doesn't this need to be done for runtime_resume as well? > > This driver doesn't seem to be doing any physical power off in its > runtime_suspend and I don't expect an I2C device to be put in a PM > domain, so possibly no need for it. I'd expect runtime PM suspend callback to power the device off through ACPI PM. For this reason the device state must be restored when it's powered on, i.e. its runtime_resume callback.
On Tue, May 9, 2017 at 6:40 PM, Sakari Ailus <sakari.ailus@iki.fi> wrote: > Hi Tomasz, > > On Tue, May 09, 2017 at 04:30:40PM +0800, Tomasz Figa wrote: >> Hi Sakari, >> >> On Tue, May 9, 2017 at 4:55 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote: >> > Hi Rajmohan, >> > >> > A few comments below... >> > >> > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: >> [snip] >> >> + rval = v4l2_async_register_subdev(&dw9714_dev->sd); >> >> + if (rval < 0) >> >> + goto err_cleanup; >> >> + >> >> + pm_runtime_enable(&client->dev); >> > >> > Getting PM runtime right doesn't seem to be easy. :-I >> > >> > pm_runtime_enable() alone doesn't do the trick. I wonder if adding >> > pm_runtime_suspend() would do the trick. >> >> Is this something specific for I2C devices? For platform devices, >> typically pm_runtime_enable() is the only thing you would need to do. > > I think you're right --- driver_probe_device() will call pm_request_idle() > to the device right after probe. So indeed calling pm_runtime_enable() is > enough. > >> >> + >> >> + return 0; >> >> + >> >> +err_cleanup: >> >> + dw9714_subdev_cleanup(dw9714_dev); >> >> + dev_err(&client->dev, "Probe failed: %d\n", rval); >> >> + return rval; >> >> +} >> >> + >> >> +static int dw9714_remove(struct i2c_client *client) >> >> +{ >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> >> + struct dw9714_device *dw9714_dev = container_of(sd, >> >> + struct dw9714_device, >> >> + sd); >> >> + >> >> + pm_runtime_disable(&client->dev); >> >> + dw9714_subdev_cleanup(dw9714_dev); >> >> + >> >> + return 0; >> >> +} >> >> + >> >> +#ifdef CONFIG_PM >> >> + >> >> +static int dw9714_runtime_suspend(struct device *dev) >> >> +{ >> >> + return 0; >> >> +} >> >> + >> >> +static int dw9714_runtime_resume(struct device *dev) >> >> +{ >> >> + return 0; >> > >> > I think it'd be fine to remove empty callbacks. >> >> It's actually a bit more complicated (if a PM domain is attached, the >> callbacks must be present), however in case of external I2C devices it >> should be fine indeed. However, AFAIK, pm_runtime_no_callbacks() >> should be called. > > I wonder if I'm missing something --- acpi_subsys_runtime_resume() first > calls acpi_dev_runtime_resume() and if all goes well, the proceeds to call > pm_generic_runtime_resume() which calls device's runtime_resume() if it's > non-NULL. > > In other words, having a runtime_resume() and runtime_suspend() callbacks > that return zero is equivalent of having neither of the callbacks. Ah, I missed the fact this device is instantiated by ACPI and it has different handling of runtime PM, which apparently means it doesn't use the code paths affected by the PM domain thing I mentioned. > >> >> > >> >> +} >> >> + >> >> +/* This function sets the vcm position, so it consumes least current */ >> >> +static int dw9714_suspend(struct device *dev) >> >> +{ >> >> + struct i2c_client *client = to_i2c_client(dev); >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> >> + struct dw9714_device *dw9714_dev = container_of(sd, >> >> + struct dw9714_device, >> >> + sd); >> >> + int ret, val; >> >> + >> >> + dev_dbg(dev, "%s\n", __func__); >> >> + >> >> + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); >> >> + val >= 0; val -= DW9714_CTRL_STEPS) { >> >> + ret = dw9714_i2c_write(client, >> >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); >> >> + if (ret) >> >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); >> >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); >> >> + } >> >> + return 0; >> >> +} >> >> + >> >> +/* >> >> + * This function sets the vcm position, so the focus position is set >> >> + * closer to the camera >> >> + */ >> >> +static int dw9714_resume(struct device *dev) >> >> +{ >> >> + struct i2c_client *client = to_i2c_client(dev); >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> >> + struct dw9714_device *dw9714_dev = container_of(sd, >> >> + struct dw9714_device, >> >> + sd); >> >> + int ret, val; >> >> + >> >> + dev_dbg(dev, "%s\n", __func__); >> >> + >> >> + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; >> >> + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; >> >> + val += DW9714_CTRL_STEPS) { >> >> + ret = dw9714_i2c_write(client, >> >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); >> >> + if (ret) >> >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); >> >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); >> >> + } >> >> + >> >> + /* restore v4l2 control values */ >> >> + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); >> > >> > Doesn't this need to be done for runtime_resume as well? >> >> This driver doesn't seem to be doing any physical power off in its >> runtime_suspend and I don't expect an I2C device to be put in a PM >> domain, so possibly no need for it. > > I'd expect runtime PM suspend callback to power the device off through ACPI > PM. For this reason the device state must be restored when it's powered on, > i.e. its runtime_resume callback. Ah, again ACPI here, that's something not usual for me. Sorry for the noise. Best regards, Tomasz
Hi Tomasz, On Tue, May 09, 2017 at 07:38:26PM +0800, Tomasz Figa wrote: > On Tue, May 9, 2017 at 6:40 PM, Sakari Ailus <sakari.ailus@iki.fi> wrote: > > Hi Tomasz, > > > > On Tue, May 09, 2017 at 04:30:40PM +0800, Tomasz Figa wrote: > >> Hi Sakari, > >> > >> On Tue, May 9, 2017 at 4:55 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote: > >> > Hi Rajmohan, > >> > > >> > A few comments below... > >> > > >> > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: > >> [snip] > >> >> + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > >> >> + if (rval < 0) > >> >> + goto err_cleanup; > >> >> + > >> >> + pm_runtime_enable(&client->dev); > >> > > >> > Getting PM runtime right doesn't seem to be easy. :-I > >> > > >> > pm_runtime_enable() alone doesn't do the trick. I wonder if adding > >> > pm_runtime_suspend() would do the trick. > >> > >> Is this something specific for I2C devices? For platform devices, > >> typically pm_runtime_enable() is the only thing you would need to do. > > > > I think you're right --- driver_probe_device() will call pm_request_idle() > > to the device right after probe. So indeed calling pm_runtime_enable() is > > enough. > > > >> >> + > >> >> + return 0; > >> >> + > >> >> +err_cleanup: > >> >> + dw9714_subdev_cleanup(dw9714_dev); > >> >> + dev_err(&client->dev, "Probe failed: %d\n", rval); > >> >> + return rval; > >> >> +} > >> >> + > >> >> +static int dw9714_remove(struct i2c_client *client) > >> >> +{ > >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); > >> >> + struct dw9714_device *dw9714_dev = container_of(sd, > >> >> + struct dw9714_device, > >> >> + sd); > >> >> + > >> >> + pm_runtime_disable(&client->dev); > >> >> + dw9714_subdev_cleanup(dw9714_dev); > >> >> + > >> >> + return 0; > >> >> +} > >> >> + > >> >> +#ifdef CONFIG_PM > >> >> + > >> >> +static int dw9714_runtime_suspend(struct device *dev) > >> >> +{ > >> >> + return 0; > >> >> +} > >> >> + > >> >> +static int dw9714_runtime_resume(struct device *dev) > >> >> +{ > >> >> + return 0; > >> > > >> > I think it'd be fine to remove empty callbacks. > >> > >> It's actually a bit more complicated (if a PM domain is attached, the > >> callbacks must be present), however in case of external I2C devices it > >> should be fine indeed. However, AFAIK, pm_runtime_no_callbacks() > >> should be called. > > > > I wonder if I'm missing something --- acpi_subsys_runtime_resume() first > > calls acpi_dev_runtime_resume() and if all goes well, the proceeds to call > > pm_generic_runtime_resume() which calls device's runtime_resume() if it's > > non-NULL. > > > > In other words, having a runtime_resume() and runtime_suspend() callbacks > > that return zero is equivalent of having neither of the callbacks. > > Ah, I missed the fact this device is instantiated by ACPI and it has > different handling of runtime PM, which apparently means it doesn't > use the code paths affected by the PM domain thing I mentioned. I have to admit I'm no expert in the topic but I'd presume that other implementations should still maintain consistent behaviour towards drivers. acpi_subsys_runtime_resume() is the PM domain runtime_resume() callback in acpi_general_pm_domain. > > > > >> > >> > > >> >> +} > >> >> + > >> >> +/* This function sets the vcm position, so it consumes least current */ > >> >> +static int dw9714_suspend(struct device *dev) > >> >> +{ > >> >> + struct i2c_client *client = to_i2c_client(dev); > >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); > >> >> + struct dw9714_device *dw9714_dev = container_of(sd, > >> >> + struct dw9714_device, > >> >> + sd); > >> >> + int ret, val; > >> >> + > >> >> + dev_dbg(dev, "%s\n", __func__); > >> >> + > >> >> + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > >> >> + val >= 0; val -= DW9714_CTRL_STEPS) { > >> >> + ret = dw9714_i2c_write(client, > >> >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > >> >> + if (ret) > >> >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); > >> >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > >> >> + } > >> >> + return 0; > >> >> +} > >> >> + > >> >> +/* > >> >> + * This function sets the vcm position, so the focus position is set > >> >> + * closer to the camera > >> >> + */ > >> >> +static int dw9714_resume(struct device *dev) > >> >> +{ > >> >> + struct i2c_client *client = to_i2c_client(dev); > >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); > >> >> + struct dw9714_device *dw9714_dev = container_of(sd, > >> >> + struct dw9714_device, > >> >> + sd); > >> >> + int ret, val; > >> >> + > >> >> + dev_dbg(dev, "%s\n", __func__); > >> >> + > >> >> + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > >> >> + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > >> >> + val += DW9714_CTRL_STEPS) { > >> >> + ret = dw9714_i2c_write(client, > >> >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > >> >> + if (ret) > >> >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); > >> >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > >> >> + } > >> >> + > >> >> + /* restore v4l2 control values */ > >> >> + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); > >> > > >> > Doesn't this need to be done for runtime_resume as well? > >> > >> This driver doesn't seem to be doing any physical power off in its > >> runtime_suspend and I don't expect an I2C device to be put in a PM > >> domain, so possibly no need for it. > > > > I'd expect runtime PM suspend callback to power the device off through ACPI > > PM. For this reason the device state must be restored when it's powered on, > > i.e. its runtime_resume callback. > > Ah, again ACPI here, that's something not usual for me. Sorry for the noise. No harm done. Very good comments in general IMO, thanks for those!
+Rafael, Kevin and Ulf, On Tue, May 9, 2017 at 8:16 PM, Sakari Ailus <sakari.ailus@iki.fi> wrote: > Hi Tomasz, > > On Tue, May 09, 2017 at 07:38:26PM +0800, Tomasz Figa wrote: >> On Tue, May 9, 2017 at 6:40 PM, Sakari Ailus <sakari.ailus@iki.fi> wrote: >> > Hi Tomasz, >> > >> > On Tue, May 09, 2017 at 04:30:40PM +0800, Tomasz Figa wrote: >> >> Hi Sakari, >> >> >> >> On Tue, May 9, 2017 at 4:55 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote: >> >> > Hi Rajmohan, >> >> > >> >> > A few comments below... >> >> > >> >> > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: >> >> [snip] >> >> >> + rval = v4l2_async_register_subdev(&dw9714_dev->sd); >> >> >> + if (rval < 0) >> >> >> + goto err_cleanup; >> >> >> + >> >> >> + pm_runtime_enable(&client->dev); >> >> > >> >> > Getting PM runtime right doesn't seem to be easy. :-I >> >> > >> >> > pm_runtime_enable() alone doesn't do the trick. I wonder if adding >> >> > pm_runtime_suspend() would do the trick. >> >> >> >> Is this something specific for I2C devices? For platform devices, >> >> typically pm_runtime_enable() is the only thing you would need to do. >> > >> > I think you're right --- driver_probe_device() will call pm_request_idle() >> > to the device right after probe. So indeed calling pm_runtime_enable() is >> > enough. >> > >> >> >> + >> >> >> + return 0; >> >> >> + >> >> >> +err_cleanup: >> >> >> + dw9714_subdev_cleanup(dw9714_dev); >> >> >> + dev_err(&client->dev, "Probe failed: %d\n", rval); >> >> >> + return rval; >> >> >> +} >> >> >> + >> >> >> +static int dw9714_remove(struct i2c_client *client) >> >> >> +{ >> >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> >> >> + struct dw9714_device *dw9714_dev = container_of(sd, >> >> >> + struct dw9714_device, >> >> >> + sd); >> >> >> + >> >> >> + pm_runtime_disable(&client->dev); >> >> >> + dw9714_subdev_cleanup(dw9714_dev); >> >> >> + >> >> >> + return 0; >> >> >> +} >> >> >> + >> >> >> +#ifdef CONFIG_PM >> >> >> + >> >> >> +static int dw9714_runtime_suspend(struct device *dev) >> >> >> +{ >> >> >> + return 0; >> >> >> +} >> >> >> + >> >> >> +static int dw9714_runtime_resume(struct device *dev) >> >> >> +{ >> >> >> + return 0; >> >> > >> >> > I think it'd be fine to remove empty callbacks. >> >> >> >> It's actually a bit more complicated (if a PM domain is attached, the >> >> callbacks must be present), however in case of external I2C devices it >> >> should be fine indeed. However, AFAIK, pm_runtime_no_callbacks() >> >> should be called. >> > >> > I wonder if I'm missing something --- acpi_subsys_runtime_resume() first >> > calls acpi_dev_runtime_resume() and if all goes well, the proceeds to call >> > pm_generic_runtime_resume() which calls device's runtime_resume() if it's >> > non-NULL. >> > >> > In other words, having a runtime_resume() and runtime_suspend() callbacks >> > that return zero is equivalent of having neither of the callbacks. >> >> Ah, I missed the fact this device is instantiated by ACPI and it has >> different handling of runtime PM, which apparently means it doesn't >> use the code paths affected by the PM domain thing I mentioned. > > I have to admit I'm no expert in the topic but I'd presume that other > implementations should still maintain consistent behaviour towards drivers. > acpi_subsys_runtime_resume() is the PM domain runtime_resume() callback in > acpi_general_pm_domain. Let's see. For platform bus this seems to be reasonable indeed - __rpm_get_callback() will use the callbacks of PM domain, device type, device class or device bus, whichever is available first, in this order. Looking at platform_bus_type, the equivalent resume callback is pm_generic_runtime_resume() and it will indeed silently return 0 if there is no dev->pm->runtime_resume. However for I2C bus, i2c_bus_type doesn't seem to have .pm defined. Type and class are device/driver-specific things, so let's assume they don't have .pm set. If the driver doesn't have .pm, then the only way __rpm_get_callback() can return a non-NULL value is when dev->pm_domain is non NULL (which seems to be the ACPI case actually). Otherwise, if __rpm_get_callback() returns NULL, pm_runtime_get*() will fail with -ENOSYS. This is because rpm_resume() calls rpm_callback(callback, dev), where callback is the value returned by __rpm_get_callback() and rpm_callback() returns -ENOSYS if callback is NULL. This is where pm_runtime_no_callbacks() comes handy, as it bypasses the code getting and calling the callback, so it doesn't return the error anymore. There is however the other side of the coin. If pm_runtime_no_callbacks() is called, all kind of callbacks are bypassed, so even the PM domain code is not invoked. This is kind of tricky, because the driver must be now aware of whether it's running under a PM domain or not and call this pm_runtime_no_callbacks() depending on the outcome, to guarantee correct operation (PM domain callbacks must be called, even if device driver doesn't have its own)... Which IMHO doesn't make sense. I guess the correct way to proceed here would be adding .pm ops to i2c_bus_type, just as it's done with platform_bus_type. > >> >> > >> >> >> >> > >> >> >> +} >> >> >> + >> >> >> +/* This function sets the vcm position, so it consumes least current */ >> >> >> +static int dw9714_suspend(struct device *dev) >> >> >> +{ >> >> >> + struct i2c_client *client = to_i2c_client(dev); >> >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> >> >> + struct dw9714_device *dw9714_dev = container_of(sd, >> >> >> + struct dw9714_device, >> >> >> + sd); >> >> >> + int ret, val; >> >> >> + >> >> >> + dev_dbg(dev, "%s\n", __func__); >> >> >> + >> >> >> + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); >> >> >> + val >= 0; val -= DW9714_CTRL_STEPS) { >> >> >> + ret = dw9714_i2c_write(client, >> >> >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); >> >> >> + if (ret) >> >> >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); >> >> >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); >> >> >> + } >> >> >> + return 0; >> >> >> +} >> >> >> + >> >> >> +/* >> >> >> + * This function sets the vcm position, so the focus position is set >> >> >> + * closer to the camera >> >> >> + */ >> >> >> +static int dw9714_resume(struct device *dev) >> >> >> +{ >> >> >> + struct i2c_client *client = to_i2c_client(dev); >> >> >> + struct v4l2_subdev *sd = i2c_get_clientdata(client); >> >> >> + struct dw9714_device *dw9714_dev = container_of(sd, >> >> >> + struct dw9714_device, >> >> >> + sd); >> >> >> + int ret, val; >> >> >> + >> >> >> + dev_dbg(dev, "%s\n", __func__); >> >> >> + >> >> >> + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; >> >> >> + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; >> >> >> + val += DW9714_CTRL_STEPS) { >> >> >> + ret = dw9714_i2c_write(client, >> >> >> + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); >> >> >> + if (ret) >> >> >> + dev_err(dev, "%s I2C failure: %d", __func__, ret); >> >> >> + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); >> >> >> + } >> >> >> + >> >> >> + /* restore v4l2 control values */ >> >> >> + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); >> >> > >> >> > Doesn't this need to be done for runtime_resume as well? >> >> >> >> This driver doesn't seem to be doing any physical power off in its >> >> runtime_suspend and I don't expect an I2C device to be put in a PM >> >> domain, so possibly no need for it. >> > >> > I'd expect runtime PM suspend callback to power the device off through ACPI >> > PM. For this reason the device state must be restored when it's powered on, >> > i.e. its runtime_resume callback. >> >> Ah, again ACPI here, that's something not usual for me. Sorry for the noise. > > No harm done. Very good comments in general IMO, thanks for those! > > -- > Kind regards, > > Sakari Ailus > e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk
On Tue, May 9, 2017 at 9:22 PM, Tomasz Figa <tfiga@chromium.org> wrote: > +Rafael, Kevin and Ulf, > > On Tue, May 9, 2017 at 8:16 PM, Sakari Ailus <sakari.ailus@iki.fi> wrote: >> Hi Tomasz, >> >> On Tue, May 09, 2017 at 07:38:26PM +0800, Tomasz Figa wrote: >>> On Tue, May 9, 2017 at 6:40 PM, Sakari Ailus <sakari.ailus@iki.fi> wrote: >>> > Hi Tomasz, >>> > >>> > On Tue, May 09, 2017 at 04:30:40PM +0800, Tomasz Figa wrote: >>> >> Hi Sakari, >>> >> >>> >> On Tue, May 9, 2017 at 4:55 AM, Sakari Ailus <sakari.ailus@iki.fi> wrote: >>> >> > Hi Rajmohan, >>> >> > >>> >> > A few comments below... >>> >> > >>> >> > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: >>> >> >> +#ifdef CONFIG_PM >>> >> >> + >>> >> >> +static int dw9714_runtime_suspend(struct device *dev) >>> >> >> +{ >>> >> >> + return 0; >>> >> >> +} >>> >> >> + >>> >> >> +static int dw9714_runtime_resume(struct device *dev) >>> >> >> +{ >>> >> >> + return 0; >>> >> > >>> >> > I think it'd be fine to remove empty callbacks. >>> >> >>> >> It's actually a bit more complicated (if a PM domain is attached, the >>> >> callbacks must be present), however in case of external I2C devices it >>> >> should be fine indeed. However, AFAIK, pm_runtime_no_callbacks() >>> >> should be called. >>> > >>> > I wonder if I'm missing something --- acpi_subsys_runtime_resume() first >>> > calls acpi_dev_runtime_resume() and if all goes well, the proceeds to call >>> > pm_generic_runtime_resume() which calls device's runtime_resume() if it's >>> > non-NULL. >>> > >>> > In other words, having a runtime_resume() and runtime_suspend() callbacks >>> > that return zero is equivalent of having neither of the callbacks. >>> >>> Ah, I missed the fact this device is instantiated by ACPI and it has >>> different handling of runtime PM, which apparently means it doesn't >>> use the code paths affected by the PM domain thing I mentioned. >> >> I have to admit I'm no expert in the topic but I'd presume that other >> implementations should still maintain consistent behaviour towards drivers. >> acpi_subsys_runtime_resume() is the PM domain runtime_resume() callback in >> acpi_general_pm_domain. > > Let's see. For platform bus this seems to be reasonable indeed - > __rpm_get_callback() will use the callbacks of PM domain, device type, > device class or device bus, whichever is available first, in this > order. Looking at platform_bus_type, the equivalent resume callback is > pm_generic_runtime_resume() and it will indeed silently return 0 if > there is no dev->pm->runtime_resume. > > However for I2C bus, i2c_bus_type doesn't seem to have .pm defined. > Type and class are device/driver-specific things, so let's assume they > don't have .pm set. If the driver doesn't have .pm, then the only way > __rpm_get_callback() can return a non-NULL value is when > dev->pm_domain is non NULL (which seems to be the ACPI case actually). > Otherwise, if __rpm_get_callback() returns NULL, pm_runtime_get*() > will fail with -ENOSYS. This is because rpm_resume() calls > rpm_callback(callback, dev), where callback is the value returned by > __rpm_get_callback() and rpm_callback() returns -ENOSYS if callback is > NULL. This is where pm_runtime_no_callbacks() comes handy, as it > bypasses the code getting and calling the callback, so it doesn't > return the error anymore. > > There is however the other side of the coin. If > pm_runtime_no_callbacks() is called, all kind of callbacks are > bypassed, so even the PM domain code is not invoked. This is kind of > tricky, because the driver must be now aware of whether it's running > under a PM domain or not and call this pm_runtime_no_callbacks() > depending on the outcome, to guarantee correct operation (PM domain > callbacks must be called, even if device driver doesn't have its > own)... Which IMHO doesn't make sense. > > I guess the correct way to proceed here would be adding .pm ops to > i2c_bus_type, just as it's done with platform_bus_type. Ah, sorry, I mean, the correct way to proceed here to make the behavior consistent. For Raj's patch, since a) the driver needs to restore the control value and b) it's supposed to be primarily instantiated by ACPI, we shouldn't hit the above problem for now. Best regards, Tomasz
Hi Sakari, Please see comments inline below. > -----Original Message----- > From: Sakari Ailus [mailto:sakari.ailus@iki.fi] > Sent: Tuesday, May 09, 2017 4:55 AM > To: Mani, Rajmohan <rajmohan.mani@intel.com> > Cc: linux-media@vger.kernel.org; mchehab@kernel.org > Subject: Re: [PATCH] dw9714: Initial driver for dw9714 VCM > > Hi Rajmohan, > > A few comments below... > > On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com > wrote: > > From: Rajmohan Mani <rajmohan.mani@intel.com> > > > > DW9714 is a 10 bit DAC, designed for linear control of voice coil > > motor. > > > > This driver creates a V4L2 subdevice and provides control to set the > > desired focus. > > > > Signed-off-by: Rajmohan Mani <rajmohan.mani@intel.com> > > --- > > drivers/media/i2c/Kconfig | 9 ++ > > drivers/media/i2c/Makefile | 1 + > > drivers/media/i2c/dw9714.c | 333 > > +++++++++++++++++++++++++++++++++++++++++++++ > > 3 files changed, 343 insertions(+) > > create mode 100644 drivers/media/i2c/dw9714.c > > > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > > index fd181c9..4f0a7ad 100644 > > --- a/drivers/media/i2c/Kconfig > > +++ b/drivers/media/i2c/Kconfig > > @@ -300,6 +300,15 @@ config VIDEO_AD5820 > > This is a driver for the AD5820 camera lens voice coil. > > It is used for example in Nokia N900 (RX-51). > > > > +config VIDEO_DW9714 > > + tristate "DW9714 lens voice coil support" > > + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER > > You should also depend on VIDEO_V4L2_SUBDEV_API . Ack > > > + ---help--- > > + This is a driver for the DW9714 camera lens voice coil. > > + DW9714 is a 10 bit DAC with 120mA output current sink > > + capability. This is designed for linear control of > > + voice coil motors, controlled via I2C serial interface. > > + > > config VIDEO_SAA7110 > > tristate "Philips SAA7110 video decoder" > > depends on VIDEO_V4L2 && I2C > > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > > index 62323ec..987bd1f 100644 > > --- a/drivers/media/i2c/Makefile > > +++ b/drivers/media/i2c/Makefile > > @@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_SAA7127) += saa7127.o > > obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o > > obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o > > obj-$(CONFIG_VIDEO_AD5820) += ad5820.o > > +obj-$(CONFIG_VIDEO_DW9714) += dw9714.o > > obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o > > obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o > > obj-$(CONFIG_VIDEO_ADV7180) += adv7180.o diff --git > > a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c new file > > mode 100644 index 0000000..276d3f2 > > --- /dev/null > > +++ b/drivers/media/i2c/dw9714.c > > @@ -0,0 +1,333 @@ > > +/* > > + * Copyright (c) 2015--2017 Intel Corporation. > > + * > > + * This program is free software; you can redistribute it and/or > > + * modify it under the terms of the GNU General Public License > > +version > > + * 2 as published by the Free Software Foundation. > > + * > > + * This program is distributed in the hope that it will be useful, > > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > > + * GNU General Public License for more details. > > + */ > > + > > +#include <linux/acpi.h> > > +#include <linux/delay.h> > > +#include <linux/i2c.h> > > +#include <linux/module.h> > > +#include <linux/pm_runtime.h> > > +#include <media/v4l2-ctrls.h> > > +#include <media/v4l2-device.h> > > + > > +#define DW9714_NAME "dw9714" > > +#define DW9714_MAX_FOCUS_POS 1023 > > +#define DW9714_CTRL_STEPS 16 /* Keep this value power of 2 > */ > > +#define DW9714_CTRL_DELAY_US 1000 > > +/* > > + * S[3:2] = 0x00, codes per step for "Linear Slope Control" > > + * S[1:0] = 0x00, step period > > + */ > > +#define DW9714_DEFAULT_S 0x0 > > +#define DW9714_VAL(data, s) (u16)((data) << 4 | (s)) > > + > > +/* dw9714 device structure */ > > +struct dw9714_device { > > + struct i2c_client *client; > > + struct v4l2_ctrl_handler ctrls_vcm; > > + struct v4l2_subdev sd; > > + u16 current_val; > > +}; > > + > > +#define to_dw9714_vcm(_ctrl) \ > > + container_of(_ctrl->handler, struct dw9714_device, ctrls_vcm) > > + > > +static int dw9714_i2c_write(struct i2c_client *client, u16 data) { > > + const int num_msg = 1; > > + int ret; > > + u16 val = cpu_to_be16(data); > > + struct i2c_msg msg = { > > + .addr = client->addr, > > + .flags = 0, > > + .len = sizeof(val), > > + .buf = (u8 *) &val, > > + }; > > + > > + ret = i2c_transfer(client->adapter, &msg, num_msg); > > + > > + /*One retry */ > > + if (ret != num_msg) > > + ret = i2c_transfer(client->adapter, &msg, num_msg); > > + > > + if (ret != num_msg) { > > + dev_err(&client->dev, "I2C write fail fail\n"); > > + return -EIO; > > + } else { > > + return 0; > > + } > > +} > > + > > +static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 > > +val) { > > + struct i2c_client *client = dw9714_dev->client; > > + int ret = -EINVAL; > > + > > + dev_dbg(&client->dev, "Setting new value VCM: %d\n", val); > > + dw9714_dev->current_val = val; > > + > > + ret = dw9714_i2c_write(client, DW9714_VAL(val, > DW9714_DEFAULT_S)); > > + return ret; > > +} > > + > > +static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl) { > > + struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl); > > + > > + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) > > + return dw9714_t_focus_vcm(dev_vcm, ctrl->val); > > + else > > + return -EINVAL; > > +} > > + > > +static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = { > > + .s_ctrl = dw9714_set_ctrl, > > +}; > > + > > +static int dw9714_init_controls(struct dw9714_device *dev_vcm) { > > + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; > > + const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops; > > + struct i2c_client *client = dev_vcm->client; > > + > > + v4l2_ctrl_handler_init(hdl, 1); > > + > > + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, > > + 0, DW9714_MAX_FOCUS_POS, 1, 0); > > + > > + if (hdl->error) > > + dev_err(&client->dev, "dw9714_init_controls fail\n"); > > + dev_vcm->sd.ctrl_handler = hdl; > > + return hdl->error; > > +} > > + > > +static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev) { > > + v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm); > > Please release the control handler after unregistering the sub-device. Ack > > > + v4l2_async_unregister_subdev(&dw9714_dev->sd); > > + v4l2_device_unregister_subdev(&dw9714_dev->sd); > > + media_entity_cleanup(&dw9714_dev->sd.entity); > > +} > > + > > +static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh > > +*fh) { > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + struct device *dev = &dw9714_dev->client->dev; > > + int rval; > > + > > + rval = pm_runtime_get_sync(dev); > > If this fails you'll need to do pm_runtime_put(dev); Ack > > > + dev_dbg(dev, "%s rval = %d\n", __func__, rval); > > + > > + return rval; > > +} > > + > > +static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh > > +*fh) { > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + struct device *dev = &dw9714_dev->client->dev; > > + > > + dev_dbg(dev, "%s\n", __func__); > > + pm_runtime_put(dev); > > + > > + return 0; > > +} > > + > > +static const struct v4l2_subdev_internal_ops dw9714_int_ops = { > > + .open = dw9714_open, > > + .close = dw9714_close, > > +}; > > + > > +static const struct v4l2_subdev_ops dw9714_ops = { }; > > You should use v4l2_subdev_internal_ops here. > I am not sure I understand what you mean here. Can you please elaborate? > > + > > +static int dw9714_probe(struct i2c_client *client, > > + const struct i2c_device_id *devid) { > > + struct dw9714_device *dw9714_dev; > > + int rval; > > + > > + dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev), > > + GFP_KERNEL); > > + > > + if (dw9714_dev == NULL) > > + return -ENOMEM; > > + > > + dw9714_dev->client = client; > > + > > + v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); > > + dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; > > + dw9714_dev->sd.internal_ops = &dw9714_int_ops; > > + > > + snprintf(dw9714_dev->sd.name, > > + sizeof(dw9714_dev->sd.name), > > + DW9714_NAME " %d-%4.4x", i2c_adapter_id(client- > >adapter), > > + client->addr); > > + > > + rval = dw9714_init_controls(dw9714_dev); > > + if (rval) > > + goto err_cleanup; > > + > > + rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL); > > + if (rval < 0) > > + goto err_cleanup; > > + > > + dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS; > > + > > + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > > + if (rval < 0) > > + goto err_cleanup; > > + > > + pm_runtime_enable(&client->dev); > > Getting PM runtime right doesn't seem to be easy. :-I > > pm_runtime_enable() alone doesn't do the trick. I wonder if adding > pm_runtime_suspend() would do the trick. > Based on the comments exchanged between you and Tomasz, I believe it is ok if we stop with just pm_runtime_enable(). P.S: Adding pm_runtime_suspend() did not result in dw9714_runtime_suspend() being invoked. > > + > > + return 0; > > + > > +err_cleanup: > > + dw9714_subdev_cleanup(dw9714_dev); > > + dev_err(&client->dev, "Probe failed: %d\n", rval); > > + return rval; > > +} > > + > > +static int dw9714_remove(struct i2c_client *client) { > > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + > > + pm_runtime_disable(&client->dev); > > + dw9714_subdev_cleanup(dw9714_dev); > > + > > + return 0; > > +} > > + > > +#ifdef CONFIG_PM > > + > > +static int dw9714_runtime_suspend(struct device *dev) { > > + return 0; > > +} > > + > > +static int dw9714_runtime_resume(struct device *dev) { > > + return 0; > > I think it'd be fine to remove empty callbacks. Given that we need to do whatever that's done in dw9714_suspend/resume functions in dw9714_runtime_suspend/resume, these functions are not going to be empty callbacks. > > > +} > > + > > +/* This function sets the vcm position, so it consumes least current > > +*/ static int dw9714_suspend(struct device *dev) { > > + struct i2c_client *client = to_i2c_client(dev); > > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + int ret, val; > > + > > + dev_dbg(dev, "%s\n", __func__); > > + > > + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > > + val >= 0; val -= DW9714_CTRL_STEPS) { > > + ret = dw9714_i2c_write(client, > > + DW9714_VAL((u16) val, > DW9714_DEFAULT_S)); > > + if (ret) > > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > > + usleep_range(DW9714_CTRL_DELAY_US, > DW9714_CTRL_DELAY_US + 10); > > + } > > + return 0; > > +} > > + > > +/* > > + * This function sets the vcm position, so the focus position is set > > + * closer to the camera > > + */ > > +static int dw9714_resume(struct device *dev) { > > + struct i2c_client *client = to_i2c_client(dev); > > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > > + struct dw9714_device *dw9714_dev = container_of(sd, > > + struct > dw9714_device, > > + sd); > > + int ret, val; > > + > > + dev_dbg(dev, "%s\n", __func__); > > + > > + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > > + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > > + val += DW9714_CTRL_STEPS) { > > + ret = dw9714_i2c_write(client, > > + DW9714_VAL((u16) val, > DW9714_DEFAULT_S)); > > + if (ret) > > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > > + usleep_range(DW9714_CTRL_DELAY_US, > DW9714_CTRL_DELAY_US + 10); > > + } > > + > > + /* restore v4l2 control values */ > > + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); > > Doesn't this need to be done for runtime_resume as well? Ack. I will add dw9714_vcm_suspend/resume functions and invoke them from dw9714_suspend/resume and dw9714_runtime_suspend/resume functions > > > + dev_dbg(dev, "%s ret = %d\n", __func__, ret); > > + return ret; > > +} > > + > > +#else > > + > > +#define dw9714_suspend NULL > > +#define dw9714_resume NULL > > +#define dw9714_runtime_suspend NULL > > +#define dw9714_runtime_resume NULL > > + > > +#endif /* CONFIG_PM */ > > + > > +#ifdef CONFIG_ACPI > > +static const struct acpi_device_id dw9714_acpi_match[] = { > > + {"DW9714", 0}, > > + {}, > > +}; > > +MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match); #endif > > + > > +static const struct i2c_device_id dw9714_id_table[] = { > > + {DW9714_NAME, 0}, > > + {} > > +}; > > + > > +MODULE_DEVICE_TABLE(i2c, dw9714_id_table); > > + > > +static const struct dev_pm_ops dw9714_pm_ops = { > > + .suspend = dw9714_suspend, > > + .resume = dw9714_resume, > > + .runtime_suspend = dw9714_runtime_suspend, > > + .runtime_resume = dw9714_runtime_resume, }; > > + > > +static struct i2c_driver dw9714_i2c_driver = { > > + .driver = { > > + .name = DW9714_NAME, > > + .pm = &dw9714_pm_ops, > > +#ifdef CONFIG_ACPI > > + .acpi_match_table = ACPI_PTR(dw9714_acpi_match), #endif > > + }, > > + .probe = dw9714_probe, > > + .remove = dw9714_remove, > > + .id_table = dw9714_id_table, > > +}; > > + > > +module_i2c_driver(dw9714_i2c_driver); > > + > > +MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); > > +MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>"); > > +MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>"); > > +MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>"); > > +MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>"); > > +MODULE_DESCRIPTION("DW9714 VCM driver"); MODULE_LICENSE("GPL"); > > -- > Regards, > > Sakari Ailus > e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig index fd181c9..4f0a7ad 100644 --- a/drivers/media/i2c/Kconfig +++ b/drivers/media/i2c/Kconfig @@ -300,6 +300,15 @@ config VIDEO_AD5820 This is a driver for the AD5820 camera lens voice coil. It is used for example in Nokia N900 (RX-51). +config VIDEO_DW9714 + tristate "DW9714 lens voice coil support" + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER + ---help--- + This is a driver for the DW9714 camera lens voice coil. + DW9714 is a 10 bit DAC with 120mA output current sink + capability. This is designed for linear control of + voice coil motors, controlled via I2C serial interface. + config VIDEO_SAA7110 tristate "Philips SAA7110 video decoder" depends on VIDEO_V4L2 && I2C diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile index 62323ec..987bd1f 100644 --- a/drivers/media/i2c/Makefile +++ b/drivers/media/i2c/Makefile @@ -21,6 +21,7 @@ obj-$(CONFIG_VIDEO_SAA7127) += saa7127.o obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o obj-$(CONFIG_VIDEO_AD5820) += ad5820.o +obj-$(CONFIG_VIDEO_DW9714) += dw9714.o obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o obj-$(CONFIG_VIDEO_ADV7180) += adv7180.o diff --git a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c new file mode 100644 index 0000000..276d3f2 --- /dev/null +++ b/drivers/media/i2c/dw9714.c @@ -0,0 +1,333 @@ +/* + * Copyright (c) 2015--2017 Intel Corporation. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License version + * 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/acpi.h> +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <media/v4l2-ctrls.h> +#include <media/v4l2-device.h> + +#define DW9714_NAME "dw9714" +#define DW9714_MAX_FOCUS_POS 1023 +#define DW9714_CTRL_STEPS 16 /* Keep this value power of 2 */ +#define DW9714_CTRL_DELAY_US 1000 +/* + * S[3:2] = 0x00, codes per step for "Linear Slope Control" + * S[1:0] = 0x00, step period + */ +#define DW9714_DEFAULT_S 0x0 +#define DW9714_VAL(data, s) (u16)((data) << 4 | (s)) + +/* dw9714 device structure */ +struct dw9714_device { + struct i2c_client *client; + struct v4l2_ctrl_handler ctrls_vcm; + struct v4l2_subdev sd; + u16 current_val; +}; + +#define to_dw9714_vcm(_ctrl) \ + container_of(_ctrl->handler, struct dw9714_device, ctrls_vcm) + +static int dw9714_i2c_write(struct i2c_client *client, u16 data) +{ + const int num_msg = 1; + int ret; + u16 val = cpu_to_be16(data); + struct i2c_msg msg = { + .addr = client->addr, + .flags = 0, + .len = sizeof(val), + .buf = (u8 *) &val, + }; + + ret = i2c_transfer(client->adapter, &msg, num_msg); + + /*One retry */ + if (ret != num_msg) + ret = i2c_transfer(client->adapter, &msg, num_msg); + + if (ret != num_msg) { + dev_err(&client->dev, "I2C write fail fail\n"); + return -EIO; + } else { + return 0; + } +} + +static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val) +{ + struct i2c_client *client = dw9714_dev->client; + int ret = -EINVAL; + + dev_dbg(&client->dev, "Setting new value VCM: %d\n", val); + dw9714_dev->current_val = val; + + ret = dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S)); + return ret; +} + +static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl) +{ + struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl); + + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) + return dw9714_t_focus_vcm(dev_vcm, ctrl->val); + else + return -EINVAL; +} + +static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = { + .s_ctrl = dw9714_set_ctrl, +}; + +static int dw9714_init_controls(struct dw9714_device *dev_vcm) +{ + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; + const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops; + struct i2c_client *client = dev_vcm->client; + + v4l2_ctrl_handler_init(hdl, 1); + + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, + 0, DW9714_MAX_FOCUS_POS, 1, 0); + + if (hdl->error) + dev_err(&client->dev, "dw9714_init_controls fail\n"); + dev_vcm->sd.ctrl_handler = hdl; + return hdl->error; +} + +static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev) +{ + v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm); + v4l2_async_unregister_subdev(&dw9714_dev->sd); + v4l2_device_unregister_subdev(&dw9714_dev->sd); + media_entity_cleanup(&dw9714_dev->sd.entity); +} + +static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) +{ + struct dw9714_device *dw9714_dev = container_of(sd, + struct dw9714_device, + sd); + struct device *dev = &dw9714_dev->client->dev; + int rval; + + rval = pm_runtime_get_sync(dev); + dev_dbg(dev, "%s rval = %d\n", __func__, rval); + + return rval; +} + +static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) +{ + struct dw9714_device *dw9714_dev = container_of(sd, + struct dw9714_device, + sd); + struct device *dev = &dw9714_dev->client->dev; + + dev_dbg(dev, "%s\n", __func__); + pm_runtime_put(dev); + + return 0; +} + +static const struct v4l2_subdev_internal_ops dw9714_int_ops = { + .open = dw9714_open, + .close = dw9714_close, +}; + +static const struct v4l2_subdev_ops dw9714_ops = { }; + +static int dw9714_probe(struct i2c_client *client, + const struct i2c_device_id *devid) +{ + struct dw9714_device *dw9714_dev; + int rval; + + dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev), + GFP_KERNEL); + + if (dw9714_dev == NULL) + return -ENOMEM; + + dw9714_dev->client = client; + + v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); + dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; + dw9714_dev->sd.internal_ops = &dw9714_int_ops; + + snprintf(dw9714_dev->sd.name, + sizeof(dw9714_dev->sd.name), + DW9714_NAME " %d-%4.4x", i2c_adapter_id(client->adapter), + client->addr); + + rval = dw9714_init_controls(dw9714_dev); + if (rval) + goto err_cleanup; + + rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL); + if (rval < 0) + goto err_cleanup; + + dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS; + + rval = v4l2_async_register_subdev(&dw9714_dev->sd); + if (rval < 0) + goto err_cleanup; + + pm_runtime_enable(&client->dev); + + return 0; + +err_cleanup: + dw9714_subdev_cleanup(dw9714_dev); + dev_err(&client->dev, "Probe failed: %d\n", rval); + return rval; +} + +static int dw9714_remove(struct i2c_client *client) +{ + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct dw9714_device *dw9714_dev = container_of(sd, + struct dw9714_device, + sd); + + pm_runtime_disable(&client->dev); + dw9714_subdev_cleanup(dw9714_dev); + + return 0; +} + +#ifdef CONFIG_PM + +static int dw9714_runtime_suspend(struct device *dev) +{ + return 0; +} + +static int dw9714_runtime_resume(struct device *dev) +{ + return 0; +} + +/* This function sets the vcm position, so it consumes least current */ +static int dw9714_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct dw9714_device *dw9714_dev = container_of(sd, + struct dw9714_device, + sd); + int ret, val; + + dev_dbg(dev, "%s\n", __func__); + + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); + val >= 0; val -= DW9714_CTRL_STEPS) { + ret = dw9714_i2c_write(client, + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); + if (ret) + dev_err(dev, "%s I2C failure: %d", __func__, ret); + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); + } + return 0; +} + +/* + * This function sets the vcm position, so the focus position is set + * closer to the camera + */ +static int dw9714_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct dw9714_device *dw9714_dev = container_of(sd, + struct dw9714_device, + sd); + int ret, val; + + dev_dbg(dev, "%s\n", __func__); + + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; + val += DW9714_CTRL_STEPS) { + ret = dw9714_i2c_write(client, + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); + if (ret) + dev_err(dev, "%s I2C failure: %d", __func__, ret); + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); + } + + /* restore v4l2 control values */ + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); + dev_dbg(dev, "%s ret = %d\n", __func__, ret); + return ret; +} + +#else + +#define dw9714_suspend NULL +#define dw9714_resume NULL +#define dw9714_runtime_suspend NULL +#define dw9714_runtime_resume NULL + +#endif /* CONFIG_PM */ + +#ifdef CONFIG_ACPI +static const struct acpi_device_id dw9714_acpi_match[] = { + {"DW9714", 0}, + {}, +}; +MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match); +#endif + +static const struct i2c_device_id dw9714_id_table[] = { + {DW9714_NAME, 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, dw9714_id_table); + +static const struct dev_pm_ops dw9714_pm_ops = { + .suspend = dw9714_suspend, + .resume = dw9714_resume, + .runtime_suspend = dw9714_runtime_suspend, + .runtime_resume = dw9714_runtime_resume, +}; + +static struct i2c_driver dw9714_i2c_driver = { + .driver = { + .name = DW9714_NAME, + .pm = &dw9714_pm_ops, +#ifdef CONFIG_ACPI + .acpi_match_table = ACPI_PTR(dw9714_acpi_match), +#endif + }, + .probe = dw9714_probe, + .remove = dw9714_remove, + .id_table = dw9714_id_table, +}; + +module_i2c_driver(dw9714_i2c_driver); + +MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); +MODULE_AUTHOR("Jian Xu Zheng <jian.xu.zheng@intel.com>"); +MODULE_AUTHOR("Yuning Pu <yuning.pu@intel.com>"); +MODULE_AUTHOR("Jouni Ukkonen <jouni.ukkonen@intel.com>"); +MODULE_AUTHOR("Tommi Franttila <tommi.franttila@intel.com>"); +MODULE_DESCRIPTION("DW9714 VCM driver"); +MODULE_LICENSE("GPL");