[V2,2/2] media: i2c: Add DW9768 VCM driver
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Message ID 20190905072142.14606-3-dongchun.zhu@mediatek.com
State New
Headers show
Series
  • media: i2c: add support for DW9768 VCM driver
Related show

Commit Message

Dongchun Zhu Sept. 5, 2019, 7:21 a.m. UTC
From: Dongchun Zhu <dongchun.zhu@mediatek.com>

This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
and provides control to set the desired focus.

The DW9768 is a 10 bit DAC with 100mA output current sink capability
from Dongwoon, designed for linear control of voice coil motor,
and controlled via I2C serial interface.

Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
---
 MAINTAINERS                |   1 +
 drivers/media/i2c/Kconfig  |  10 ++
 drivers/media/i2c/Makefile |   1 +
 drivers/media/i2c/dw9768.c | 349 +++++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 361 insertions(+)
 create mode 100644 drivers/media/i2c/dw9768.c

Comments

Sakari Ailus Sept. 5, 2019, 8:21 a.m. UTC | #1
Hi Dongchun,

Thanks for the update. A few comments below.

On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> 
> This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
> and provides control to set the desired focus.
> 
> The DW9768 is a 10 bit DAC with 100mA output current sink capability
> from Dongwoon, designed for linear control of voice coil motor,
> and controlled via I2C serial interface.
> 
> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  MAINTAINERS                |   1 +
>  drivers/media/i2c/Kconfig  |  10 ++
>  drivers/media/i2c/Makefile |   1 +
>  drivers/media/i2c/dw9768.c | 349 +++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 361 insertions(+)
>  create mode 100644 drivers/media/i2c/dw9768.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 192a671..c5c9a0e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4976,6 +4976,7 @@ M:	Dongchun Zhu <dongchun.zhu@mediatek.com>
>  L:	linux-media@vger.kernel.org
>  T:	git git://linuxtv.org/media_tree.git
>  S:	Maintained
> +F:	drivers/media/i2c/dw9768.c
>  F:	Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.txt
>  
>  DONGWOON DW9807 LENS VOICE COIL DRIVER
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 79ce9ec..dfb665c 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -1016,6 +1016,16 @@ config VIDEO_DW9714
>  	  capability. This is designed for linear control of
>  	  voice coil motors, controlled via I2C serial interface.
>  
> +config VIDEO_DW9768
> +	tristate "DW9768 lens voice coil support"
> +	depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
> +	depends on VIDEO_V4L2_SUBDEV_API
> +	help
> +	  This is a driver for the DW9768 camera lens voice coil.
> +	  DW9768 is a 10 bit DAC with 100mA output current sink
> +	  capability. This is designed for linear control of
> +	  voice coil motors, controlled via I2C serial interface.
> +
>  config VIDEO_DW9807_VCM
>  	tristate "DW9807 lens voice coil support"
>  	depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index fd4ea86..2561239 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -24,6 +24,7 @@ obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o
>  obj-$(CONFIG_VIDEO_AD5820)  += ad5820.o
>  obj-$(CONFIG_VIDEO_AK7375)  += ak7375.o
>  obj-$(CONFIG_VIDEO_DW9714)  += dw9714.o
> +obj-$(CONFIG_VIDEO_DW9768)  += dw9768.o
>  obj-$(CONFIG_VIDEO_DW9807_VCM)  += dw9807-vcm.o
>  obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
>  obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o
> diff --git a/drivers/media/i2c/dw9768.c b/drivers/media/i2c/dw9768.c
> new file mode 100644
> index 0000000..66d1712
> --- /dev/null
> +++ b/drivers/media/i2c/dw9768.c
> @@ -0,0 +1,349 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2019 MediaTek Inc.
> +
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/pm_runtime.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-subdev.h>
> +
> +#define DW9768_NAME				"dw9768"
> +#define DW9768_MAX_FOCUS_POS			1023
> +/*
> + * This sets the minimum granularity for the focus positions.
> + * A value of 1 gives maximum accuracy for a desired focus position
> + */
> +#define DW9768_FOCUS_STEPS			1
> +/*
> + * DW9768 separates two registers to control the VCM position.
> + * One for MSB value, another is LSB value.
> + */
> +#define DW9768_REG_MASK_MSB			0x03
> +#define DW9768_REG_MASK_LSB			0xff
> +#define DW9768_SET_POSITION_ADDR                0x03
> +
> +#define DW9768_CMD_DELAY			0xff
> +#define DW9768_CTRL_DELAY_US			5000
> +
> +#define DW9768_DAC_SHIFT			8
> +
> +/* dw9768 device structure */
> +struct dw9768 {
> +	struct v4l2_ctrl_handler ctrls;
> +	struct v4l2_subdev sd;
> +	struct regulator *vin;
> +	struct regulator *vdd;
> +};
> +
> +static inline struct dw9768 *to_dw9768_vcm(struct v4l2_ctrl *ctrl)
> +{
> +	return container_of(ctrl->handler, struct dw9768, ctrls);
> +}
> +
> +static inline struct dw9768 *sd_to_dw9768_vcm(struct v4l2_subdev *subdev)
> +{
> +	return container_of(subdev, struct dw9768, sd);
> +}
> +
> +struct regval_list {
> +	unsigned char reg_num;
> +	unsigned char value;
> +};
> +
> +static struct regval_list dw9768_init_regs[] = {
> +	{0x02, 0x02},
> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +	{0x06, 0x41},
> +	{0x07, 0x39},

These need to be documented. Please add #defines for the register addresses
and bits in the registers as needed.

The writes would better be done as function calls; the same applies to the
delays.

> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static struct regval_list dw9768_release_regs[] = {
> +	{0x02, 0x00},
> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +	{0x01, 0x00},

Same here.

> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
> +			      unsigned char value)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +	int ret;
> +
> +	if (reg == DW9768_CMD_DELAY  && value == DW9768_CMD_DELAY)
> +		usleep_range(DW9768_CTRL_DELAY_US,
> +			     DW9768_CTRL_DELAY_US + 100);
> +	else
> +		ret = i2c_smbus_write_byte_data(client, reg, value);
> +	return ret;
> +}
> +
> +static int dw9768_write_array(struct dw9768 *dw9768, struct regval_list *vals,
> +			      u32 len)
> +{
> +	unsigned int i;
> +	int ret;
> +
> +	for (i = 0; i < len; i++) {
> +		ret = dw9768_write_smbus(dw9768, vals->reg_num, vals->value);
> +		if (ret < 0)
> +			return ret;
> +	}
> +	return 0;
> +}
> +
> +static int dw9768_set_position(struct dw9768 *dw9768, u16 val)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +	u8 addr[2];
> +
> +	addr[0] = (val >> DW9768_DAC_SHIFT) & DW9768_REG_MASK_MSB;
> +	addr[1] = val & DW9768_REG_MASK_LSB;
> +
> +	return i2c_smbus_write_block_data(client, DW9768_SET_POSITION_ADDR,
> +					  ARRAY_SIZE(addr), addr);
> +}
> +
> +static int dw9768_release(struct dw9768 *dw9768)
> +{
> +	return dw9768_write_array(dw9768, dw9768_release_regs,
> +				  ARRAY_SIZE(dw9768_release_regs));
> +}
> +
> +static int dw9768_init(struct dw9768 *dw9768)
> +{
> +	return dw9768_write_array(dw9768, dw9768_init_regs,
> +				  ARRAY_SIZE(dw9768_init_regs));
> +}
> +
> +/* Power handling */
> +static int dw9768_power_off(struct dw9768 *dw9768)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +	int ret;
> +
> +	ret = dw9768_release(dw9768);
> +	if (ret)
> +		dev_err(&client->dev, "dw9768 release failed!\n");
> +
> +	ret = regulator_disable(dw9768->vin);
> +	if (ret)
> +		return ret;

You'll need to disable the other regulator unconditionally here.

> +
> +	return regulator_disable(dw9768->vdd);
> +}
> +
> +static int dw9768_power_on(struct dw9768 *dw9768)
> +{
> +	int ret;
> +
> +	ret = regulator_enable(dw9768->vin);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = regulator_enable(dw9768->vdd);
> +	if (ret < 0)

You'll need another label to disable only vin.

> +		return ret;
> +
> +	ret = dw9768_init(dw9768);
> +	if (ret < 0)
> +		goto fail;
> +
> +	return 0;
> +
> +fail:
> +	regulator_disable(dw9768->vin);
> +	regulator_disable(dw9768->vdd);
> +
> +	return ret;
> +}
> +
> +static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +	struct dw9768 *dw9768 = to_dw9768_vcm(ctrl);
> +
> +	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
> +		return dw9768_set_position(dw9768, ctrl->val);
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_ctrl_ops dw9768_vcm_ctrl_ops = {
> +	.s_ctrl = dw9768_set_ctrl,
> +};
> +
> +static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> +	int ret;
> +
> +	ret = pm_runtime_get_sync(sd->dev);
> +	if (ret < 0) {
> +		pm_runtime_put_noidle(sd->dev);
> +		return ret;
> +	}
> +
> +	return 0;
> +}
> +
> +static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> +	pm_runtime_put(sd->dev);
> +
> +	return 0;
> +}
> +
> +static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
> +	.open = dw9768_open,
> +	.close = dw9768_close,
> +};
> +
> +static const struct v4l2_subdev_ops dw9768_ops = { };
> +
> +static void dw9768_subdev_cleanup(struct dw9768 *dw9768)
> +{
> +	v4l2_async_unregister_subdev(&dw9768->sd);
> +	v4l2_ctrl_handler_free(&dw9768->ctrls);
> +	media_entity_cleanup(&dw9768->sd.entity);
> +}
> +
> +static int dw9768_init_controls(struct dw9768 *dw9768)
> +{
> +	struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
> +	const struct v4l2_ctrl_ops *ops = &dw9768_vcm_ctrl_ops;
> +
> +	v4l2_ctrl_handler_init(hdl, 1);
> +
> +	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
> +			  0, DW9768_MAX_FOCUS_POS, DW9768_FOCUS_STEPS, 0);
> +
> +	if (hdl->error)
> +		return hdl->error;
> +
> +	dw9768->sd.ctrl_handler = hdl;
> +
> +	return 0;
> +}
> +
> +static int dw9768_probe(struct i2c_client *client)
> +{
> +	struct device *dev = &client->dev;
> +	struct dw9768 *dw9768;
> +	int ret;
> +
> +	dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
> +	if (!dw9768)
> +		return -ENOMEM;
> +
> +	dw9768->vin = devm_regulator_get(dev, "vin");
> +	if (IS_ERR(dw9768->vin)) {
> +		ret = PTR_ERR(dw9768->vin);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "cannot get vin regulator\n");
> +		return ret;
> +	}
> +
> +	dw9768->vdd = devm_regulator_get(dev, "vdd");
> +	if (IS_ERR(dw9768->vdd)) {
> +		ret = PTR_ERR(dw9768->vdd);
> +		if (ret != -EPROBE_DEFER)
> +			dev_err(dev, "cannot get vdd regulator\n");
> +		return ret;
> +	}
> +
> +	v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
> +	dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
> +	dw9768->sd.internal_ops = &dw9768_int_ops;
> +
> +	ret = dw9768_init_controls(dw9768);
> +	if (ret)
> +		goto err_cleanup;
> +
> +	ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
> +	if (ret < 0)
> +		goto err_cleanup;
> +
> +	dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
> +
> +	ret = v4l2_async_register_subdev(&dw9768->sd);
> +	if (ret < 0)
> +		goto err_cleanup;
> +
> +	pm_runtime_enable(dev);
> +
> +	return 0;
> +
> +err_cleanup:
> +	dw9768_subdev_cleanup(dw9768);
> +	return ret;
> +}
> +
> +static int dw9768_remove(struct i2c_client *client)
> +{
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> +
> +	dw9768_subdev_cleanup(dw9768);
> +	pm_runtime_disable(&client->dev);
> +	if (!pm_runtime_status_suspended(&client->dev))
> +		dw9768_power_off(dw9768);
> +	pm_runtime_set_suspended(&client->dev);
> +
> +	return 0;
> +}
> +
> +static int __maybe_unused dw9768_vcm_suspend(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> +
> +	return dw9768_power_off(dw9768);

Please merge this function with dw9768_power_off(); same for
dw9768_vcm_resume() below.

> +}
> +
> +static int __maybe_unused dw9768_vcm_resume(struct device *dev)
> +{
> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);
> +	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> +
> +	return dw9768_power_on(dw9768);
> +}
> +
> +static const struct i2c_device_id dw9768_id_table[] = {
> +	{ DW9768_NAME, 0 },
> +	{ },

Could you drop the I²C ID table?

> +};
> +MODULE_DEVICE_TABLE(i2c, dw9768_id_table);
> +
> +static const struct of_device_id dw9768_of_table[] = {
> +	{ .compatible = "dongwoon,dw9768" },
> +	{ },
> +};
> +MODULE_DEVICE_TABLE(of, dw9768_of_table);
> +
> +static const struct dev_pm_ops dw9768_pm_ops = {
> +	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
> +				pm_runtime_force_resume)
> +	SET_RUNTIME_PM_OPS(dw9768_vcm_suspend, dw9768_vcm_resume, NULL)
> +};
> +
> +static struct i2c_driver dw9768_i2c_driver = {
> +	.driver = {
> +		.name = DW9768_NAME,
> +		.pm = &dw9768_pm_ops,
> +		.of_match_table = dw9768_of_table,
> +	},
> +	.probe_new  = dw9768_probe,
> +	.remove = dw9768_remove,
> +	.id_table = dw9768_id_table,
> +};
> +
> +module_i2c_driver(dw9768_i2c_driver);
> +
> +MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
> +MODULE_DESCRIPTION("DW9768 VCM driver");
> +MODULE_LICENSE("GPL v2");
Tomasz Figa Sept. 5, 2019, 8:28 a.m. UTC | #2
Hi Dongchun,

On Thu, Sep 5, 2019 at 4:22 PM <dongchun.zhu@mediatek.com> wrote:
>
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
>
> This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
> and provides control to set the desired focus.
>
> The DW9768 is a 10 bit DAC with 100mA output current sink capability
> from Dongwoon, designed for linear control of voice coil motor,
> and controlled via I2C serial interface.
>
> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  MAINTAINERS                |   1 +
>  drivers/media/i2c/Kconfig  |  10 ++
>  drivers/media/i2c/Makefile |   1 +
>  drivers/media/i2c/dw9768.c | 349 +++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 361 insertions(+)
>  create mode 100644 drivers/media/i2c/dw9768.c
>

Thanks for v2! Please see my comments inline.

> diff --git a/MAINTAINERS b/MAINTAINERS
> index 192a671..c5c9a0e 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -4976,6 +4976,7 @@ M:        Dongchun Zhu <dongchun.zhu@mediatek.com>
>  L:     linux-media@vger.kernel.org
>  T:     git git://linuxtv.org/media_tree.git
>  S:     Maintained
> +F:     drivers/media/i2c/dw9768.c
>  F:     Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.txt
>
>  DONGWOON DW9807 LENS VOICE COIL DRIVER
> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
> index 79ce9ec..dfb665c 100644
> --- a/drivers/media/i2c/Kconfig
> +++ b/drivers/media/i2c/Kconfig
> @@ -1016,6 +1016,16 @@ config VIDEO_DW9714
>           capability. This is designed for linear control of
>           voice coil motors, controlled via I2C serial interface.
>
> +config VIDEO_DW9768
> +       tristate "DW9768 lens voice coil support"
> +       depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
> +       depends on VIDEO_V4L2_SUBDEV_API
> +       help
> +         This is a driver for the DW9768 camera lens voice coil.
> +         DW9768 is a 10 bit DAC with 100mA output current sink
> +         capability. This is designed for linear control of
> +         voice coil motors, controlled via I2C serial interface.
> +
>  config VIDEO_DW9807_VCM
>         tristate "DW9807 lens voice coil support"
>         depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
> index fd4ea86..2561239 100644
> --- a/drivers/media/i2c/Makefile
> +++ b/drivers/media/i2c/Makefile
> @@ -24,6 +24,7 @@ obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o
>  obj-$(CONFIG_VIDEO_AD5820)  += ad5820.o
>  obj-$(CONFIG_VIDEO_AK7375)  += ak7375.o
>  obj-$(CONFIG_VIDEO_DW9714)  += dw9714.o
> +obj-$(CONFIG_VIDEO_DW9768)  += dw9768.o
>  obj-$(CONFIG_VIDEO_DW9807_VCM)  += dw9807-vcm.o
>  obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
>  obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o
> diff --git a/drivers/media/i2c/dw9768.c b/drivers/media/i2c/dw9768.c
> new file mode 100644
> index 0000000..66d1712
> --- /dev/null
> +++ b/drivers/media/i2c/dw9768.c
> @@ -0,0 +1,349 @@
> +// SPDX-License-Identifier: GPL-2.0
> +// Copyright (c) 2019 MediaTek Inc.
> +
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/module.h>
> +#include <linux/regulator/consumer.h>
> +#include <linux/pm_runtime.h>
> +#include <media/v4l2-ctrls.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-subdev.h>
> +
> +#define DW9768_NAME                            "dw9768"
> +#define DW9768_MAX_FOCUS_POS                   1023
> +/*
> + * This sets the minimum granularity for the focus positions.
> + * A value of 1 gives maximum accuracy for a desired focus position
> + */
> +#define DW9768_FOCUS_STEPS                     1
> +/*
> + * DW9768 separates two registers to control the VCM position.
> + * One for MSB value, another is LSB value.
> + */
> +#define DW9768_REG_MASK_MSB                    0x03
> +#define DW9768_REG_MASK_LSB                    0xff
> +#define DW9768_SET_POSITION_ADDR                0x03
> +
> +#define DW9768_CMD_DELAY                       0xff
> +#define DW9768_CTRL_DELAY_US                   5000
> +
> +#define DW9768_DAC_SHIFT                       8
> +
> +/* dw9768 device structure */
> +struct dw9768 {
> +       struct v4l2_ctrl_handler ctrls;
> +       struct v4l2_subdev sd;
> +       struct regulator *vin;
> +       struct regulator *vdd;
> +};
> +
> +static inline struct dw9768 *to_dw9768_vcm(struct v4l2_ctrl *ctrl)
> +{
> +       return container_of(ctrl->handler, struct dw9768, ctrls);
> +}
> +
> +static inline struct dw9768 *sd_to_dw9768_vcm(struct v4l2_subdev *subdev)
> +{
> +       return container_of(subdev, struct dw9768, sd);
> +}
> +
> +struct regval_list {
> +       unsigned char reg_num;
> +       unsigned char value;
> +};
> +
> +static struct regval_list dw9768_init_regs[] = {
> +       {0x02, 0x02},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +       {0x06, 0x41},
> +       {0x07, 0x39},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static struct regval_list dw9768_release_regs[] = {
> +       {0x02, 0x00},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +       {0x01, 0x00},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
> +                             unsigned char value)
> +{
> +       struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +       int ret;
> +
> +       if (reg == DW9768_CMD_DELAY  && value == DW9768_CMD_DELAY)

Do we really need both to be set to this command?

> +               usleep_range(DW9768_CTRL_DELAY_US,
> +                            DW9768_CTRL_DELAY_US + 100);
> +       else
> +               ret = i2c_smbus_write_byte_data(client, reg, value);
> +       return ret;
> +}

Is there any reason to have this as a separate function and not just
implemented inside the function below?

> +
> +static int dw9768_write_array(struct dw9768 *dw9768, struct regval_list *vals,
> +                             u32 len)
> +{
> +       unsigned int i;
> +       int ret;
> +
> +       for (i = 0; i < len; i++) {
> +               ret = dw9768_write_smbus(dw9768, vals->reg_num, vals->value);
> +               if (ret < 0)
> +                       return ret;
> +       }
> +       return 0;
> +}
> +
> +static int dw9768_set_position(struct dw9768 *dw9768, u16 val)
> +{
> +       struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +       u8 addr[2];
> +
> +       addr[0] = (val >> DW9768_DAC_SHIFT) & DW9768_REG_MASK_MSB;
> +       addr[1] = val & DW9768_REG_MASK_LSB;
> +
> +       return i2c_smbus_write_block_data(client, DW9768_SET_POSITION_ADDR,
> +                                         ARRAY_SIZE(addr), addr);
> +}
> +
> +static int dw9768_release(struct dw9768 *dw9768)
> +{
> +       return dw9768_write_array(dw9768, dw9768_release_regs,
> +                                 ARRAY_SIZE(dw9768_release_regs));
> +}
> +
> +static int dw9768_init(struct dw9768 *dw9768)
> +{
> +       return dw9768_write_array(dw9768, dw9768_init_regs,
> +                                 ARRAY_SIZE(dw9768_init_regs));
> +}

Given that the 2 functions above are just called from 1 place,
wouldn't it make sense to just call dw9768_write_array() directly from
there?

> +
> +/* Power handling */
> +static int dw9768_power_off(struct dw9768 *dw9768)
> +{
> +       struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +       int ret;
> +
> +       ret = dw9768_release(dw9768);
> +       if (ret)
> +               dev_err(&client->dev, "dw9768 release failed!\n");
> +
> +       ret = regulator_disable(dw9768->vin);
> +       if (ret)
> +               return ret;
> +
> +       return regulator_disable(dw9768->vdd);
> +}
> +
> +static int dw9768_power_on(struct dw9768 *dw9768)
> +{
> +       int ret;
> +
> +       ret = regulator_enable(dw9768->vin);
> +       if (ret < 0)
> +               return ret;
> +
> +       ret = regulator_enable(dw9768->vdd);
> +       if (ret < 0)
> +               return ret;
> +
> +       ret = dw9768_init(dw9768);
> +       if (ret < 0)
> +               goto fail;
> +
> +       return 0;
> +
> +fail:
> +       regulator_disable(dw9768->vin);
> +       regulator_disable(dw9768->vdd);
> +
> +       return ret;
> +}
> +
> +static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
> +{
> +       struct dw9768 *dw9768 = to_dw9768_vcm(ctrl);
> +
> +       if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
> +               return dw9768_set_position(dw9768, ctrl->val);
> +
> +       return 0;
> +}
> +
> +static const struct v4l2_ctrl_ops dw9768_vcm_ctrl_ops = {
> +       .s_ctrl = dw9768_set_ctrl,
> +};
> +
> +static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> +       int ret;
> +
> +       ret = pm_runtime_get_sync(sd->dev);
> +       if (ret < 0) {
> +               pm_runtime_put_noidle(sd->dev);
> +               return ret;
> +       }
> +
> +       return 0;
> +}
> +
> +static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
> +{
> +       pm_runtime_put(sd->dev);
> +
> +       return 0;
> +}
> +
> +static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
> +       .open = dw9768_open,
> +       .close = dw9768_close,
> +};
> +
> +static const struct v4l2_subdev_ops dw9768_ops = { };
> +
> +static void dw9768_subdev_cleanup(struct dw9768 *dw9768)
> +{
> +       v4l2_async_unregister_subdev(&dw9768->sd);
> +       v4l2_ctrl_handler_free(&dw9768->ctrls);
> +       media_entity_cleanup(&dw9768->sd.entity);
> +}
> +
> +static int dw9768_init_controls(struct dw9768 *dw9768)
> +{
> +       struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
> +       const struct v4l2_ctrl_ops *ops = &dw9768_vcm_ctrl_ops;
> +
> +       v4l2_ctrl_handler_init(hdl, 1);
> +
> +       v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
> +                         0, DW9768_MAX_FOCUS_POS, DW9768_FOCUS_STEPS, 0);
> +
> +       if (hdl->error)
> +               return hdl->error;
> +
> +       dw9768->sd.ctrl_handler = hdl;
> +
> +       return 0;
> +}
> +
> +static int dw9768_probe(struct i2c_client *client)
> +{
> +       struct device *dev = &client->dev;
> +       struct dw9768 *dw9768;
> +       int ret;
> +
> +       dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
> +       if (!dw9768)
> +               return -ENOMEM;
> +
> +       dw9768->vin = devm_regulator_get(dev, "vin");
> +       if (IS_ERR(dw9768->vin)) {
> +               ret = PTR_ERR(dw9768->vin);
> +               if (ret != -EPROBE_DEFER)
> +                       dev_err(dev, "cannot get vin regulator\n");
> +               return ret;
> +       }
> +
> +       dw9768->vdd = devm_regulator_get(dev, "vdd");
> +       if (IS_ERR(dw9768->vdd)) {
> +               ret = PTR_ERR(dw9768->vdd);
> +               if (ret != -EPROBE_DEFER)
> +                       dev_err(dev, "cannot get vdd regulator\n");
> +               return ret;
> +       }

Any reason not to use the regulator bulk API, as already done in the
fixup patch I shared with you earlier [1]?

[1] https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+/1757579

Best regards,
Tomasz
Andy Shevchenko Sept. 5, 2019, 10:19 a.m. UTC | #3
On Thu, Sep 05, 2019 at 11:21:34AM +0300, Sakari Ailus wrote:
> On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
> > From: Dongchun Zhu <dongchun.zhu@mediatek.com>

> > +static const struct i2c_device_id dw9768_id_table[] = {
> > +	{ DW9768_NAME, 0 },
> > +	{ },
> 
> Could you drop the I²C ID table?

But why?
It will allow you to instanciate the device from user space.

+Cc: Javier.

Javier, is it needed in new code?
Andy Shevchenko Sept. 5, 2019, 10:26 a.m. UTC | #4
On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> 
> This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
> and provides control to set the desired focus.
> 
> The DW9768 is a 10 bit DAC with 100mA output current sink capability
> from Dongwoon, designed for linear control of voice coil motor,
> and controlled via I2C serial interface.

> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  MAINTAINERS                |   1 +

This should go to the same patch, where you introduce a record in the
MAINTAINERS database.

> +#define DW9768_SET_POSITION_ADDR                0x03

Indentation issue.

> +static struct regval_list dw9768_init_regs[] = {
> +	{0x02, 0x02},
> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +	{0x06, 0x41},
> +	{0x07, 0x39},
> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static struct regval_list dw9768_release_regs[] = {
> +	{0x02, 0x00},
> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +	{0x01, 0x00},
> +	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
> +			      unsigned char value)
> +{
> +	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +	int ret;
> +

> +	if (reg == DW9768_CMD_DELAY  && value == DW9768_CMD_DELAY)

Indentation issue.
But see other's comments.

> +		usleep_range(DW9768_CTRL_DELAY_US,
> +			     DW9768_CTRL_DELAY_US + 100);

> +	else

This needs an explanation.

> +		ret = i2c_smbus_write_byte_data(client, reg, value);
> +	return ret;
> +}

I'm wondering if we can benefit from regmap I²C API in this driver.

> +static int __maybe_unused dw9768_vcm_suspend(struct device *dev)
> +{

> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);

isn't is simple dev_get_drvdata() ?

> +	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> +
> +	return dw9768_power_off(dw9768);
> +}
> +
> +static int __maybe_unused dw9768_vcm_resume(struct device *dev)
> +{

> +	struct i2c_client *client = to_i2c_client(dev);
> +	struct v4l2_subdev *sd = i2c_get_clientdata(client);

Ditto.

> +	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> +
> +	return dw9768_power_on(dw9768);
> +}

> +static const struct i2c_device_id dw9768_id_table[] = {
> +	{ DW9768_NAME, 0 },

> +	{ },

No comma.

> +};

> +static const struct of_device_id dw9768_of_table[] = {
> +	{ .compatible = "dongwoon,dw9768" },

> +	{ },

Ditto.

> +};
Sakari Ailus Sept. 5, 2019, 10:40 a.m. UTC | #5
On Thu, Sep 05, 2019 at 01:19:08PM +0300, Andy Shevchenko wrote:
> On Thu, Sep 05, 2019 at 11:21:34AM +0300, Sakari Ailus wrote:
> > On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
> > > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> 
> > > +static const struct i2c_device_id dw9768_id_table[] = {
> > > +	{ DW9768_NAME, 0 },
> > > +	{ },
> > 
> > Could you drop the I²C ID table?
> 
> But why?
> It will allow you to instanciate the device from user space.

The device is supposed to be present in DT (or ACPI tables) already.

> 
> +Cc: Javier.
> 
> Javier, is it needed in new code?
Javier Martinez Canillas Sept. 5, 2019, 10:57 a.m. UTC | #6
On 9/5/19 12:40 PM, Sakari Ailus wrote:
> On Thu, Sep 05, 2019 at 01:19:08PM +0300, Andy Shevchenko wrote:
>> On Thu, Sep 05, 2019 at 11:21:34AM +0300, Sakari Ailus wrote:
>>> On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
>>>> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
>>
>>>> +static const struct i2c_device_id dw9768_id_table[] = {
>>>> +	{ DW9768_NAME, 0 },
>>>> +	{ },
>>>
>>> Could you drop the I²C ID table?
>>
>> But why?
>> It will allow you to instanciate the device from user space.

Yes, the I2C device table is still needed if the device can be instantiated
from user-space using the sysfs interface, or otherwise the module won't be
automatically loaded.

Kieran posted a "[PATCH RFC] modpost: Support I2C Aliases from OF tables"
patch that adds a MODULE_DEVICE_TABLE(i2c_of, ..) macro so modpost could
add legacy I2C modalias using the information in the OF device ID tables:

https://patchwork.kernel.org/patch/11038861/

If that lands, then we could get rid of the I2C device tables altogether
for non-legacy I2C drivers.

> 
> The device is supposed to be present in DT (or ACPI tables) already.
>

Agreed. Also by looking at the driver's probe function I see that the
device lookups a 'vin' and 'vdd' regulators supplies and it fails if
aren't defined, so it can't be instantiated from user-space anyways.

BTW, these two regulators supplies should be listed as 'vin-supply'
and 'vdd-supply' as required properties in the DT binding document.

Best regards,
Andy Shevchenko Sept. 5, 2019, 11:36 a.m. UTC | #7
On Thu, Sep 05, 2019 at 12:57:34PM +0200, Javier Martinez Canillas wrote:
> On 9/5/19 12:40 PM, Sakari Ailus wrote:
> > On Thu, Sep 05, 2019 at 01:19:08PM +0300, Andy Shevchenko wrote:
> >> On Thu, Sep 05, 2019 at 11:21:34AM +0300, Sakari Ailus wrote:
> >>> On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
> >>>> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> >>
> >>>> +static const struct i2c_device_id dw9768_id_table[] = {
> >>>> +	{ DW9768_NAME, 0 },
> >>>> +	{ },
> >>>
> >>> Could you drop the I²C ID table?
> >>
> >> But why?
> >> It will allow you to instanciate the device from user space.
> 
> Yes, the I2C device table is still needed if the device can be instantiated
> from user-space using the sysfs interface, or otherwise the module won't be
> automatically loaded.
> 
> Kieran posted a "[PATCH RFC] modpost: Support I2C Aliases from OF tables"
> patch that adds a MODULE_DEVICE_TABLE(i2c_of, ..) macro so modpost could
> add legacy I2C modalias using the information in the OF device ID tables:
> 
> https://patchwork.kernel.org/patch/11038861/
> 
> If that lands, then we could get rid of the I2C device tables altogether
> for non-legacy I2C drivers.
> 
> > 
> > The device is supposed to be present in DT (or ACPI tables) already.
> >
> 
> Agreed. Also by looking at the driver's probe function I see that the
> device lookups a 'vin' and 'vdd' regulators supplies and it fails if
> aren't defined, so it can't be instantiated from user-space anyways.

Thank you for clarifications!

So, it can use ->probe_new() in that case.

> 
> BTW, these two regulators supplies should be listed as 'vin-supply'
> and 'vdd-supply' as required properties in the DT binding document.
Tomasz Figa Oct. 9, 2019, 4:40 a.m. UTC | #8
Hi Dongchun,

On Thu, Sep 5, 2019 at 4:22 PM <dongchun.zhu@mediatek.com> wrote:
>
> From: Dongchun Zhu <dongchun.zhu@mediatek.com>
>
> This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
> and provides control to set the desired focus.
>
> The DW9768 is a 10 bit DAC with 100mA output current sink capability
> from Dongwoon, designed for linear control of voice coil motor,
> and controlled via I2C serial interface.
>
> Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> ---
>  MAINTAINERS                |   1 +
>  drivers/media/i2c/Kconfig  |  10 ++
>  drivers/media/i2c/Makefile |   1 +
>  drivers/media/i2c/dw9768.c | 349 +++++++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 361 insertions(+)
>  create mode 100644 drivers/media/i2c/dw9768.c
>

Please see my further comments inline.

[snip]
> +struct regval_list {
> +       unsigned char reg_num;
> +       unsigned char value;

nit: Since we have strictly sized values here, should we use u8 for
both fields instead?

> +};
> +
> +static struct regval_list dw9768_init_regs[] = {
> +       {0x02, 0x02},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +       {0x06, 0x41},
> +       {0x07, 0x39},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static struct regval_list dw9768_release_regs[] = {
> +       {0x02, 0x00},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +       {0x01, 0x00},
> +       {DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> +};
> +
> +static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
> +                             unsigned char value)

Should we use u8 for the last two arguments here as well?

> +{
> +       struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +       int ret;
> +
> +       if (reg == DW9768_CMD_DELAY  && value == DW9768_CMD_DELAY)
> +               usleep_range(DW9768_CTRL_DELAY_US,
> +                            DW9768_CTRL_DELAY_US + 100);

ret will be uninitialized if we go this path.

> +       else
> +               ret = i2c_smbus_write_byte_data(client, reg, value);
> +       return ret;
> +}
> +
> +static int dw9768_write_array(struct dw9768 *dw9768, struct regval_list *vals,
> +                             u32 len)

Since len is an array size, should we use size_t instead?

> +{
> +       unsigned int i;

size_t?

> +       int ret;
> +
> +       for (i = 0; i < len; i++) {
> +               ret = dw9768_write_smbus(dw9768, vals->reg_num, vals->value);

This should refer to vals[i] instead.

> +               if (ret < 0)
> +                       return ret;
> +       }
> +       return 0;
> +}
> +
> +static int dw9768_set_position(struct dw9768 *dw9768, u16 val)
> +{
> +       struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +       u8 addr[2];
> +
> +       addr[0] = (val >> DW9768_DAC_SHIFT) & DW9768_REG_MASK_MSB;
> +       addr[1] = val & DW9768_REG_MASK_LSB;
> +
> +       return i2c_smbus_write_block_data(client, DW9768_SET_POSITION_ADDR,
> +                                         ARRAY_SIZE(addr), addr);

As we discovered earlier, i2c_smbus_write_block_data() uses a
different protocol from what we expected. Please change to
i2c_smbus_write_word_data(), as per our downstream changes.

> +}
> +
> +static int dw9768_release(struct dw9768 *dw9768)
> +{
> +       return dw9768_write_array(dw9768, dw9768_release_regs,
> +                                 ARRAY_SIZE(dw9768_release_regs));
> +}
> +
> +static int dw9768_init(struct dw9768 *dw9768)
> +{
> +       return dw9768_write_array(dw9768, dw9768_init_regs,
> +                                 ARRAY_SIZE(dw9768_init_regs));
> +}
> +
> +/* Power handling */
> +static int dw9768_power_off(struct dw9768 *dw9768)
> +{
> +       struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> +       int ret;
> +
> +       ret = dw9768_release(dw9768);
> +       if (ret)
> +               dev_err(&client->dev, "dw9768 release failed!\n");
> +
> +       ret = regulator_disable(dw9768->vin);
> +       if (ret)
> +               return ret;
> +
> +       return regulator_disable(dw9768->vdd);
> +}
> +
> +static int dw9768_power_on(struct dw9768 *dw9768)
> +{
> +       int ret;
> +
> +       ret = regulator_enable(dw9768->vin);
> +       if (ret < 0)
> +               return ret;
> +
> +       ret = regulator_enable(dw9768->vdd);
> +       if (ret < 0)
> +               return ret;

There is at least T_opr = 200 us of delay needed here. Would you be
able to add a comment and a corresponding usleep_range() call? I guess
the range of (300, 400) would be enough on the safe side.

Best regards,
Tomasz
Dongchun Zhu Jan. 20, 2020, 8:34 a.m. UTC | #9
Hello Andy,

Thanks for the review. Please see the replies below.

On Mon, 2019-09-05 at 12:26 +0200, Andy Shevchenko wrote:
> On Thu, Sep 05, 2019 at 03:21:42PM +0800, dongchun.zhu@mediatek.com wrote:
> > From: Dongchun Zhu <dongchun.zhu@mediatek.com>
> >
> > This patch adds a V4L2 sub-device driver for DW9768 lens voice coil,
> > and provides control to set the desired focus.
> >
> > The DW9768 is a 10 bit DAC with 100mA output current sink capability
> > from Dongwoon, designed for linear control of voice coil motor, and
> > controlled via I2C serial interface.
> 
> > Signed-off-by: Dongchun Zhu <dongchun.zhu@mediatek.com>
> > ---
> >  MAINTAINERS                |   1 +
> 
> This should go to the same patch, where you introduce a record in the MAINTAINERS database.
> 
> > +#define DW9768_SET_POSITION_ADDR                0x03
> 
> Indentation issue.
> 

Fixed in next release.

> > +static struct regval_list dw9768_init_regs[] = {
> > +{0x02, 0x02},
> > +{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> > +{0x06, 0x41},
> > +{0x07, 0x39},
> > +{DW9768_CMD_DELAY, DW9768_CMD_DELAY}, };
> > +
> > +static struct regval_list dw9768_release_regs[] = {
> > +{0x02, 0x00},
> > +{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
> > +{0x01, 0x00},
> > +{DW9768_CMD_DELAY, DW9768_CMD_DELAY}, };
> > +
> > +static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
> > +      unsigned char value)
> > +{
> > +struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
> > +int ret;
> > +
> 
> > +if (reg == DW9768_CMD_DELAY  && value == DW9768_CMD_DELAY)
> 
> Indentation issue.
> But see other's comments.
> 
> > +usleep_range(DW9768_CTRL_DELAY_US,
> > +     DW9768_CTRL_DELAY_US + 100);
> 
> > +else
> 
> This needs an explanation.
> 

Fixed in next release.

> > +ret = i2c_smbus_write_byte_data(client, reg, value);
> > +return ret;
> > +}
> 
> I'm wondering if we can benefit from regmap I²C API in this driver.
> 
> > +static int __maybe_unused dw9768_vcm_suspend(struct device *dev) {
> 
> > +struct i2c_client *client = to_i2c_client(dev);
> > +struct v4l2_subdev *sd = i2c_get_clientdata(client);
> 
> isn't is simple dev_get_drvdata() ?
> 

As discussed in another group mail, even dev_set_drvdata() is set when
probe, the pointer that point to the private device struct changes when
using dev_get_drvdata() API.
Then resume/power on would result in kernel exception in
regulator_enable.

This is so weird.
We filed one Google issue to trace this behavior.
https://partnerissuetracker.corp.google.com/issues/147957975

I am wondering whether there is any condition of the use of
dev_get_drvdata().
I checked the other drivers and found that most devices that use
dev_get_drvdata() are platform devices or non i2c client devices.
So maybe dw9768 or other media/i2c devices cannot support
dev_get_drvdata()?

> > +struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> > +
> > +return dw9768_power_off(dw9768);
> > +}
> > +
> > +static int __maybe_unused dw9768_vcm_resume(struct device *dev) {
> 
> > +struct i2c_client *client = to_i2c_client(dev);
> > +struct v4l2_subdev *sd = i2c_get_clientdata(client);
> 
> Ditto.
> 
> > +struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
> > +
> > +return dw9768_power_on(dw9768);
> > +}
> 
> > +static const struct i2c_device_id dw9768_id_table[] = {
> > +{ DW9768_NAME, 0 },
> 
> > +{ },
> 
> No comma.
> 

This struct would be removed in next release.

> > +};
> 
> > +static const struct of_device_id dw9768_of_table[] = {
> > +{ .compatible = "dongwoon,dw9768" },
> 
> > +{ },
> 
> Ditto.
> 

Fixed in next release.

> > +};
> 
> --
> With Best Regards,
> Andy Shevchenko
> 
> 
> *********************MEDIATEK Confidential/Internal Use*********************

Patch
diff mbox series

diff --git a/MAINTAINERS b/MAINTAINERS
index 192a671..c5c9a0e 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -4976,6 +4976,7 @@  M:	Dongchun Zhu <dongchun.zhu@mediatek.com>
 L:	linux-media@vger.kernel.org
 T:	git git://linuxtv.org/media_tree.git
 S:	Maintained
+F:	drivers/media/i2c/dw9768.c
 F:	Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.txt
 
 DONGWOON DW9807 LENS VOICE COIL DRIVER
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index 79ce9ec..dfb665c 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -1016,6 +1016,16 @@  config VIDEO_DW9714
 	  capability. This is designed for linear control of
 	  voice coil motors, controlled via I2C serial interface.
 
+config VIDEO_DW9768
+	tristate "DW9768 lens voice coil support"
+	depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
+	depends on VIDEO_V4L2_SUBDEV_API
+	help
+	  This is a driver for the DW9768 camera lens voice coil.
+	  DW9768 is a 10 bit DAC with 100mA output current sink
+	  capability. This is designed for linear control of
+	  voice coil motors, controlled via I2C serial interface.
+
 config VIDEO_DW9807_VCM
 	tristate "DW9807 lens voice coil support"
 	depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index fd4ea86..2561239 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -24,6 +24,7 @@  obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o
 obj-$(CONFIG_VIDEO_AD5820)  += ad5820.o
 obj-$(CONFIG_VIDEO_AK7375)  += ak7375.o
 obj-$(CONFIG_VIDEO_DW9714)  += dw9714.o
+obj-$(CONFIG_VIDEO_DW9768)  += dw9768.o
 obj-$(CONFIG_VIDEO_DW9807_VCM)  += dw9807-vcm.o
 obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
 obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o
diff --git a/drivers/media/i2c/dw9768.c b/drivers/media/i2c/dw9768.c
new file mode 100644
index 0000000..66d1712
--- /dev/null
+++ b/drivers/media/i2c/dw9768.c
@@ -0,0 +1,349 @@ 
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 MediaTek Inc.
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/pm_runtime.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-subdev.h>
+
+#define DW9768_NAME				"dw9768"
+#define DW9768_MAX_FOCUS_POS			1023
+/*
+ * This sets the minimum granularity for the focus positions.
+ * A value of 1 gives maximum accuracy for a desired focus position
+ */
+#define DW9768_FOCUS_STEPS			1
+/*
+ * DW9768 separates two registers to control the VCM position.
+ * One for MSB value, another is LSB value.
+ */
+#define DW9768_REG_MASK_MSB			0x03
+#define DW9768_REG_MASK_LSB			0xff
+#define DW9768_SET_POSITION_ADDR                0x03
+
+#define DW9768_CMD_DELAY			0xff
+#define DW9768_CTRL_DELAY_US			5000
+
+#define DW9768_DAC_SHIFT			8
+
+/* dw9768 device structure */
+struct dw9768 {
+	struct v4l2_ctrl_handler ctrls;
+	struct v4l2_subdev sd;
+	struct regulator *vin;
+	struct regulator *vdd;
+};
+
+static inline struct dw9768 *to_dw9768_vcm(struct v4l2_ctrl *ctrl)
+{
+	return container_of(ctrl->handler, struct dw9768, ctrls);
+}
+
+static inline struct dw9768 *sd_to_dw9768_vcm(struct v4l2_subdev *subdev)
+{
+	return container_of(subdev, struct dw9768, sd);
+}
+
+struct regval_list {
+	unsigned char reg_num;
+	unsigned char value;
+};
+
+static struct regval_list dw9768_init_regs[] = {
+	{0x02, 0x02},
+	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+	{0x06, 0x41},
+	{0x07, 0x39},
+	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+};
+
+static struct regval_list dw9768_release_regs[] = {
+	{0x02, 0x00},
+	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+	{0x01, 0x00},
+	{DW9768_CMD_DELAY, DW9768_CMD_DELAY},
+};
+
+static int dw9768_write_smbus(struct dw9768 *dw9768, unsigned char reg,
+			      unsigned char value)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+	int ret;
+
+	if (reg == DW9768_CMD_DELAY  && value == DW9768_CMD_DELAY)
+		usleep_range(DW9768_CTRL_DELAY_US,
+			     DW9768_CTRL_DELAY_US + 100);
+	else
+		ret = i2c_smbus_write_byte_data(client, reg, value);
+	return ret;
+}
+
+static int dw9768_write_array(struct dw9768 *dw9768, struct regval_list *vals,
+			      u32 len)
+{
+	unsigned int i;
+	int ret;
+
+	for (i = 0; i < len; i++) {
+		ret = dw9768_write_smbus(dw9768, vals->reg_num, vals->value);
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
+static int dw9768_set_position(struct dw9768 *dw9768, u16 val)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+	u8 addr[2];
+
+	addr[0] = (val >> DW9768_DAC_SHIFT) & DW9768_REG_MASK_MSB;
+	addr[1] = val & DW9768_REG_MASK_LSB;
+
+	return i2c_smbus_write_block_data(client, DW9768_SET_POSITION_ADDR,
+					  ARRAY_SIZE(addr), addr);
+}
+
+static int dw9768_release(struct dw9768 *dw9768)
+{
+	return dw9768_write_array(dw9768, dw9768_release_regs,
+				  ARRAY_SIZE(dw9768_release_regs));
+}
+
+static int dw9768_init(struct dw9768 *dw9768)
+{
+	return dw9768_write_array(dw9768, dw9768_init_regs,
+				  ARRAY_SIZE(dw9768_init_regs));
+}
+
+/* Power handling */
+static int dw9768_power_off(struct dw9768 *dw9768)
+{
+	struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+	int ret;
+
+	ret = dw9768_release(dw9768);
+	if (ret)
+		dev_err(&client->dev, "dw9768 release failed!\n");
+
+	ret = regulator_disable(dw9768->vin);
+	if (ret)
+		return ret;
+
+	return regulator_disable(dw9768->vdd);
+}
+
+static int dw9768_power_on(struct dw9768 *dw9768)
+{
+	int ret;
+
+	ret = regulator_enable(dw9768->vin);
+	if (ret < 0)
+		return ret;
+
+	ret = regulator_enable(dw9768->vdd);
+	if (ret < 0)
+		return ret;
+
+	ret = dw9768_init(dw9768);
+	if (ret < 0)
+		goto fail;
+
+	return 0;
+
+fail:
+	regulator_disable(dw9768->vin);
+	regulator_disable(dw9768->vdd);
+
+	return ret;
+}
+
+static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+	struct dw9768 *dw9768 = to_dw9768_vcm(ctrl);
+
+	if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
+		return dw9768_set_position(dw9768, ctrl->val);
+
+	return 0;
+}
+
+static const struct v4l2_ctrl_ops dw9768_vcm_ctrl_ops = {
+	.s_ctrl = dw9768_set_ctrl,
+};
+
+static int dw9768_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	int ret;
+
+	ret = pm_runtime_get_sync(sd->dev);
+	if (ret < 0) {
+		pm_runtime_put_noidle(sd->dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+	pm_runtime_put(sd->dev);
+
+	return 0;
+}
+
+static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
+	.open = dw9768_open,
+	.close = dw9768_close,
+};
+
+static const struct v4l2_subdev_ops dw9768_ops = { };
+
+static void dw9768_subdev_cleanup(struct dw9768 *dw9768)
+{
+	v4l2_async_unregister_subdev(&dw9768->sd);
+	v4l2_ctrl_handler_free(&dw9768->ctrls);
+	media_entity_cleanup(&dw9768->sd.entity);
+}
+
+static int dw9768_init_controls(struct dw9768 *dw9768)
+{
+	struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
+	const struct v4l2_ctrl_ops *ops = &dw9768_vcm_ctrl_ops;
+
+	v4l2_ctrl_handler_init(hdl, 1);
+
+	v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE,
+			  0, DW9768_MAX_FOCUS_POS, DW9768_FOCUS_STEPS, 0);
+
+	if (hdl->error)
+		return hdl->error;
+
+	dw9768->sd.ctrl_handler = hdl;
+
+	return 0;
+}
+
+static int dw9768_probe(struct i2c_client *client)
+{
+	struct device *dev = &client->dev;
+	struct dw9768 *dw9768;
+	int ret;
+
+	dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
+	if (!dw9768)
+		return -ENOMEM;
+
+	dw9768->vin = devm_regulator_get(dev, "vin");
+	if (IS_ERR(dw9768->vin)) {
+		ret = PTR_ERR(dw9768->vin);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "cannot get vin regulator\n");
+		return ret;
+	}
+
+	dw9768->vdd = devm_regulator_get(dev, "vdd");
+	if (IS_ERR(dw9768->vdd)) {
+		ret = PTR_ERR(dw9768->vdd);
+		if (ret != -EPROBE_DEFER)
+			dev_err(dev, "cannot get vdd regulator\n");
+		return ret;
+	}
+
+	v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
+	dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+	dw9768->sd.internal_ops = &dw9768_int_ops;
+
+	ret = dw9768_init_controls(dw9768);
+	if (ret)
+		goto err_cleanup;
+
+	ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
+	if (ret < 0)
+		goto err_cleanup;
+
+	dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
+
+	ret = v4l2_async_register_subdev(&dw9768->sd);
+	if (ret < 0)
+		goto err_cleanup;
+
+	pm_runtime_enable(dev);
+
+	return 0;
+
+err_cleanup:
+	dw9768_subdev_cleanup(dw9768);
+	return ret;
+}
+
+static int dw9768_remove(struct i2c_client *client)
+{
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
+
+	dw9768_subdev_cleanup(dw9768);
+	pm_runtime_disable(&client->dev);
+	if (!pm_runtime_status_suspended(&client->dev))
+		dw9768_power_off(dw9768);
+	pm_runtime_set_suspended(&client->dev);
+
+	return 0;
+}
+
+static int __maybe_unused dw9768_vcm_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
+
+	return dw9768_power_off(dw9768);
+}
+
+static int __maybe_unused dw9768_vcm_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct dw9768 *dw9768 = sd_to_dw9768_vcm(sd);
+
+	return dw9768_power_on(dw9768);
+}
+
+static const struct i2c_device_id dw9768_id_table[] = {
+	{ DW9768_NAME, 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(i2c, dw9768_id_table);
+
+static const struct of_device_id dw9768_of_table[] = {
+	{ .compatible = "dongwoon,dw9768" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, dw9768_of_table);
+
+static const struct dev_pm_ops dw9768_pm_ops = {
+	SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+				pm_runtime_force_resume)
+	SET_RUNTIME_PM_OPS(dw9768_vcm_suspend, dw9768_vcm_resume, NULL)
+};
+
+static struct i2c_driver dw9768_i2c_driver = {
+	.driver = {
+		.name = DW9768_NAME,
+		.pm = &dw9768_pm_ops,
+		.of_match_table = dw9768_of_table,
+	},
+	.probe_new  = dw9768_probe,
+	.remove = dw9768_remove,
+	.id_table = dw9768_id_table,
+};
+
+module_i2c_driver(dw9768_i2c_driver);
+
+MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu@mediatek.com>");
+MODULE_DESCRIPTION("DW9768 VCM driver");
+MODULE_LICENSE("GPL v2");