| Message ID | 20200719221103.91644-3-contact@artur-rojek.eu (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | input: ADC joystick driver & DT bindings | expand |
On Mon, 20 Jul 2020 00:11:03 +0200 Artur Rojek <contact@artur-rojek.eu> wrote: > Add a driver for joystick devices connected to ADC controllers > supporting the Industrial I/O subsystem. > > Signed-off-by: Artur Rojek <contact@artur-rojek.eu> > Tested-by: Paul Cercueil <paul@crapouillou.net> > Tested-by: Heiko Stuebner <heiko@sntech.de> > Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Looks good to me. Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> I'm assuming this will got through input. Jonathan > --- > > Changes: > > v2: - sanity check supported channel format on probe, > - rename adc_joystick_disable to a more sensible adc_joystick_cleanup, > - enforce correct axis order by checking the `reg` property of > child nodes > > v3-v5: no change > > v6: - remove redundant `<linux/of.h>` > - set `val` for each endianness case in their respective branches > - pass received error codes to return value of `adc_joystick_set_axes` > - change `(bits >> 3) > 2` to `bits > 16` for readability > - drop `of_match_ptr` > > v7: no change > > v8: - respect scan index when reading channel data, > - solve sparse warnings related to *_to_cpu calls, > - simplify channel count logic, > - drop the redundant comma from adc_joystick_of_match[] > > drivers/input/joystick/Kconfig | 10 + > drivers/input/joystick/Makefile | 1 + > drivers/input/joystick/adc-joystick.c | 253 ++++++++++++++++++++++++++ > 3 files changed, 264 insertions(+) > create mode 100644 drivers/input/joystick/adc-joystick.c > > diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig > index eb031b7a4866..b080f0cfb068 100644 > --- a/drivers/input/joystick/Kconfig > +++ b/drivers/input/joystick/Kconfig > @@ -42,6 +42,16 @@ config JOYSTICK_A3D > To compile this driver as a module, choose M here: the > module will be called a3d. > > +config JOYSTICK_ADC > + tristate "Simple joystick connected over ADC" > + depends on IIO > + select IIO_BUFFER_CB > + help > + Say Y here if you have a simple joystick connected over ADC. > + > + To compile this driver as a module, choose M here: the > + module will be called adc-joystick. > + > config JOYSTICK_ADI > tristate "Logitech ADI digital joysticks and gamepads" > select GAMEPORT > diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile > index 8656023f6ef5..58232b3057d3 100644 > --- a/drivers/input/joystick/Makefile > +++ b/drivers/input/joystick/Makefile > @@ -6,6 +6,7 @@ > # Each configuration option enables a list of files. > > obj-$(CONFIG_JOYSTICK_A3D) += a3d.o > +obj-$(CONFIG_JOYSTICK_ADC) += adc-joystick.o > obj-$(CONFIG_JOYSTICK_ADI) += adi.o > obj-$(CONFIG_JOYSTICK_AMIGA) += amijoy.o > obj-$(CONFIG_JOYSTICK_AS5011) += as5011.o > diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c > new file mode 100644 > index 000000000000..a2c570de0b8a > --- /dev/null > +++ b/drivers/input/joystick/adc-joystick.c > @@ -0,0 +1,253 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Input driver for joysticks connected over ADC. > + * Copyright (c) 2019-2020 Artur Rojek <contact@artur-rojek.eu> > + */ > +#include <linux/ctype.h> > +#include <linux/input.h> > +#include <linux/iio/iio.h> > +#include <linux/iio/consumer.h> > +#include <linux/module.h> > +#include <linux/platform_device.h> > +#include <linux/property.h> > + > +struct adc_joystick_axis { > + u32 code; > + s32 range[2]; > + s32 fuzz; > + s32 flat; > +}; > + > +struct adc_joystick { > + struct input_dev *input; > + struct iio_cb_buffer *buffer; > + struct adc_joystick_axis *axes; > + struct iio_channel *chans; > + int num_chans; > +}; > + > +static int adc_joystick_handle(const void *data, void *private) > +{ > + struct adc_joystick *joy = private; > + enum iio_endian endianness; > + int bytes, msb, val, idx, i; > + bool sign; > + > + bytes = joy->chans[0].channel->scan_type.storagebits >> 3; > + > + for (i = 0; i < joy->num_chans; ++i) { > + idx = joy->chans[i].channel->scan_index; > + endianness = joy->chans[i].channel->scan_type.endianness; > + msb = joy->chans[i].channel->scan_type.realbits - 1; > + sign = (tolower(joy->chans[i].channel->scan_type.sign) == 's'); > + > + switch (bytes) { > + case 1: > + val = ((const u8 *)data)[idx]; > + break; > + case 2: > + if (endianness == IIO_BE) > + val = be16_to_cpu(((const __be16 *)data)[idx]); > + else if (endianness == IIO_LE) > + val = le16_to_cpu(((const __le16 *)data)[idx]); > + else /* IIO_CPU */ > + val = ((const u16 *)data)[idx]; > + break; > + default: > + return -EINVAL; > + } > + > + val >>= joy->chans[i].channel->scan_type.shift; > + if (sign) > + val = sign_extend32(val, msb); > + else > + val &= GENMASK(msb, 0); > + input_report_abs(joy->input, joy->axes[i].code, val); > + } > + > + input_sync(joy->input); > + > + return 0; > +} > + > +static int adc_joystick_open(struct input_dev *dev) > +{ > + struct adc_joystick *joy = input_get_drvdata(dev); > + int ret; > + > + ret = iio_channel_start_all_cb(joy->buffer); > + if (ret) > + dev_err(dev->dev.parent, "Unable to start callback buffer"); > + > + return ret; > +} > + > +static void adc_joystick_close(struct input_dev *dev) > +{ > + struct adc_joystick *joy = input_get_drvdata(dev); > + > + iio_channel_stop_all_cb(joy->buffer); > +} > + > +static void adc_joystick_cleanup(void *data) > +{ > + iio_channel_release_all_cb(data); > +} > + > +static int adc_joystick_set_axes(struct device *dev, struct adc_joystick *joy) > +{ > + struct adc_joystick_axis *axes; > + struct fwnode_handle *child; > + int num_axes, ret, i; > + > + num_axes = device_get_child_node_count(dev); > + if (!num_axes) { > + dev_err(dev, "Unable to find child nodes"); > + return -EINVAL; > + } > + > + if (num_axes != joy->num_chans) { > + dev_err(dev, "Got %d child nodes for %d channels", > + num_axes, joy->num_chans); > + return -EINVAL; > + } > + > + axes = devm_kmalloc_array(dev, num_axes, sizeof(*axes), GFP_KERNEL); > + if (!axes) > + return -ENOMEM; > + > + device_for_each_child_node(dev, child) { > + ret = fwnode_property_read_u32(child, "reg", &i); > + if (ret) { > + dev_err(dev, "reg invalid or missing"); > + goto err; > + } > + > + if (i >= num_axes) { > + ret = -EINVAL; > + dev_err(dev, "No matching axis for reg %d", i); > + goto err; > + } > + > + ret = fwnode_property_read_u32(child, "linux,code", > + &axes[i].code); > + if (ret) { > + dev_err(dev, "linux,code invalid or missing"); > + goto err; > + } > + > + ret = fwnode_property_read_u32_array(child, "abs-range", > + axes[i].range, 2); > + if (ret) { > + dev_err(dev, "abs-range invalid or missing"); > + goto err; > + } > + > + fwnode_property_read_u32(child, "abs-fuzz", > + &axes[i].fuzz); > + fwnode_property_read_u32(child, "abs-flat", > + &axes[i].flat); > + > + input_set_abs_params(joy->input, axes[i].code, > + axes[i].range[0], axes[i].range[1], > + axes[i].fuzz, > + axes[i].flat); > + input_set_capability(joy->input, EV_ABS, axes[i].code); > + } > + > + joy->axes = axes; > + > + return 0; > + > +err: > + fwnode_handle_put(child); > + return ret; > +} > + > +static int adc_joystick_probe(struct platform_device *pdev) > +{ > + struct device *dev = &pdev->dev; > + struct adc_joystick *joy; > + struct input_dev *input; > + int bits, ret, i; > + > + joy = devm_kzalloc(dev, sizeof(*joy), GFP_KERNEL); > + if (!joy) > + return -ENOMEM; > + > + joy->chans = devm_iio_channel_get_all(dev); > + if (IS_ERR(joy->chans)) { > + ret = PTR_ERR(joy->chans); > + if (ret != -EPROBE_DEFER) > + dev_err(dev, "Unable to get IIO channels"); > + return ret; > + } > + > + /* Count how many channels we got. NULL terminated. */ > + for (i = 0; joy->chans[i].indio_dev; ++i) { > + bits = joy->chans[i].channel->scan_type.storagebits; > + if (!bits || (bits > 16)) { > + dev_err(dev, "Unsupported channel storage size"); > + return -EINVAL; > + } > + if (bits != joy->chans[0].channel->scan_type.storagebits) { > + dev_err(dev, "Channels must have equal storage size"); > + return -EINVAL; > + } > + } > + joy->num_chans = i; > + > + input = devm_input_allocate_device(dev); > + if (!input) { > + dev_err(dev, "Unable to allocate input device"); > + return -ENOMEM; > + } > + > + joy->input = input; > + input->name = pdev->name; > + input->id.bustype = BUS_HOST; > + input->open = adc_joystick_open; > + input->close = adc_joystick_close; > + > + ret = adc_joystick_set_axes(dev, joy); > + if (ret) > + return ret; > + > + input_set_drvdata(input, joy); > + ret = input_register_device(input); > + if (ret) { > + dev_err(dev, "Unable to register input device: %d", ret); > + return ret; > + } > + > + joy->buffer = iio_channel_get_all_cb(dev, adc_joystick_handle, joy); > + if (IS_ERR(joy->buffer)) { > + dev_err(dev, "Unable to allocate callback buffer"); > + return PTR_ERR(joy->buffer); > + } > + > + ret = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer); > + if (ret) > + dev_err(dev, "Unable to add action"); > + > + return ret; > +} > + > +static const struct of_device_id adc_joystick_of_match[] = { > + { .compatible = "adc-joystick", }, > + { } > +}; > +MODULE_DEVICE_TABLE(of, adc_joystick_of_match); > + > +static struct platform_driver adc_joystick_driver = { > + .driver = { > + .name = "adc-joystick", > + .of_match_table = adc_joystick_of_match, > + }, > + .probe = adc_joystick_probe, > +}; > +module_platform_driver(adc_joystick_driver); > + > +MODULE_DESCRIPTION("Input driver for joysticks connected over ADC"); > +MODULE_AUTHOR("Artur Rojek <contact@artur-rojek.eu>"); > +MODULE_LICENSE("GPL");
diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig index eb031b7a4866..b080f0cfb068 100644 --- a/drivers/input/joystick/Kconfig +++ b/drivers/input/joystick/Kconfig @@ -42,6 +42,16 @@ config JOYSTICK_A3D To compile this driver as a module, choose M here: the module will be called a3d. +config JOYSTICK_ADC + tristate "Simple joystick connected over ADC" + depends on IIO + select IIO_BUFFER_CB + help + Say Y here if you have a simple joystick connected over ADC. + + To compile this driver as a module, choose M here: the + module will be called adc-joystick. + config JOYSTICK_ADI tristate "Logitech ADI digital joysticks and gamepads" select GAMEPORT diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile index 8656023f6ef5..58232b3057d3 100644 --- a/drivers/input/joystick/Makefile +++ b/drivers/input/joystick/Makefile @@ -6,6 +6,7 @@ # Each configuration option enables a list of files. obj-$(CONFIG_JOYSTICK_A3D) += a3d.o +obj-$(CONFIG_JOYSTICK_ADC) += adc-joystick.o obj-$(CONFIG_JOYSTICK_ADI) += adi.o obj-$(CONFIG_JOYSTICK_AMIGA) += amijoy.o obj-$(CONFIG_JOYSTICK_AS5011) += as5011.o diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c new file mode 100644 index 000000000000..a2c570de0b8a --- /dev/null +++ b/drivers/input/joystick/adc-joystick.c @@ -0,0 +1,253 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Input driver for joysticks connected over ADC. + * Copyright (c) 2019-2020 Artur Rojek <contact@artur-rojek.eu> + */ +#include <linux/ctype.h> +#include <linux/input.h> +#include <linux/iio/iio.h> +#include <linux/iio/consumer.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/property.h> + +struct adc_joystick_axis { + u32 code; + s32 range[2]; + s32 fuzz; + s32 flat; +}; + +struct adc_joystick { + struct input_dev *input; + struct iio_cb_buffer *buffer; + struct adc_joystick_axis *axes; + struct iio_channel *chans; + int num_chans; +}; + +static int adc_joystick_handle(const void *data, void *private) +{ + struct adc_joystick *joy = private; + enum iio_endian endianness; + int bytes, msb, val, idx, i; + bool sign; + + bytes = joy->chans[0].channel->scan_type.storagebits >> 3; + + for (i = 0; i < joy->num_chans; ++i) { + idx = joy->chans[i].channel->scan_index; + endianness = joy->chans[i].channel->scan_type.endianness; + msb = joy->chans[i].channel->scan_type.realbits - 1; + sign = (tolower(joy->chans[i].channel->scan_type.sign) == 's'); + + switch (bytes) { + case 1: + val = ((const u8 *)data)[idx]; + break; + case 2: + if (endianness == IIO_BE) + val = be16_to_cpu(((const __be16 *)data)[idx]); + else if (endianness == IIO_LE) + val = le16_to_cpu(((const __le16 *)data)[idx]); + else /* IIO_CPU */ + val = ((const u16 *)data)[idx]; + break; + default: + return -EINVAL; + } + + val >>= joy->chans[i].channel->scan_type.shift; + if (sign) + val = sign_extend32(val, msb); + else + val &= GENMASK(msb, 0); + input_report_abs(joy->input, joy->axes[i].code, val); + } + + input_sync(joy->input); + + return 0; +} + +static int adc_joystick_open(struct input_dev *dev) +{ + struct adc_joystick *joy = input_get_drvdata(dev); + int ret; + + ret = iio_channel_start_all_cb(joy->buffer); + if (ret) + dev_err(dev->dev.parent, "Unable to start callback buffer"); + + return ret; +} + +static void adc_joystick_close(struct input_dev *dev) +{ + struct adc_joystick *joy = input_get_drvdata(dev); + + iio_channel_stop_all_cb(joy->buffer); +} + +static void adc_joystick_cleanup(void *data) +{ + iio_channel_release_all_cb(data); +} + +static int adc_joystick_set_axes(struct device *dev, struct adc_joystick *joy) +{ + struct adc_joystick_axis *axes; + struct fwnode_handle *child; + int num_axes, ret, i; + + num_axes = device_get_child_node_count(dev); + if (!num_axes) { + dev_err(dev, "Unable to find child nodes"); + return -EINVAL; + } + + if (num_axes != joy->num_chans) { + dev_err(dev, "Got %d child nodes for %d channels", + num_axes, joy->num_chans); + return -EINVAL; + } + + axes = devm_kmalloc_array(dev, num_axes, sizeof(*axes), GFP_KERNEL); + if (!axes) + return -ENOMEM; + + device_for_each_child_node(dev, child) { + ret = fwnode_property_read_u32(child, "reg", &i); + if (ret) { + dev_err(dev, "reg invalid or missing"); + goto err; + } + + if (i >= num_axes) { + ret = -EINVAL; + dev_err(dev, "No matching axis for reg %d", i); + goto err; + } + + ret = fwnode_property_read_u32(child, "linux,code", + &axes[i].code); + if (ret) { + dev_err(dev, "linux,code invalid or missing"); + goto err; + } + + ret = fwnode_property_read_u32_array(child, "abs-range", + axes[i].range, 2); + if (ret) { + dev_err(dev, "abs-range invalid or missing"); + goto err; + } + + fwnode_property_read_u32(child, "abs-fuzz", + &axes[i].fuzz); + fwnode_property_read_u32(child, "abs-flat", + &axes[i].flat); + + input_set_abs_params(joy->input, axes[i].code, + axes[i].range[0], axes[i].range[1], + axes[i].fuzz, + axes[i].flat); + input_set_capability(joy->input, EV_ABS, axes[i].code); + } + + joy->axes = axes; + + return 0; + +err: + fwnode_handle_put(child); + return ret; +} + +static int adc_joystick_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct adc_joystick *joy; + struct input_dev *input; + int bits, ret, i; + + joy = devm_kzalloc(dev, sizeof(*joy), GFP_KERNEL); + if (!joy) + return -ENOMEM; + + joy->chans = devm_iio_channel_get_all(dev); + if (IS_ERR(joy->chans)) { + ret = PTR_ERR(joy->chans); + if (ret != -EPROBE_DEFER) + dev_err(dev, "Unable to get IIO channels"); + return ret; + } + + /* Count how many channels we got. NULL terminated. */ + for (i = 0; joy->chans[i].indio_dev; ++i) { + bits = joy->chans[i].channel->scan_type.storagebits; + if (!bits || (bits > 16)) { + dev_err(dev, "Unsupported channel storage size"); + return -EINVAL; + } + if (bits != joy->chans[0].channel->scan_type.storagebits) { + dev_err(dev, "Channels must have equal storage size"); + return -EINVAL; + } + } + joy->num_chans = i; + + input = devm_input_allocate_device(dev); + if (!input) { + dev_err(dev, "Unable to allocate input device"); + return -ENOMEM; + } + + joy->input = input; + input->name = pdev->name; + input->id.bustype = BUS_HOST; + input->open = adc_joystick_open; + input->close = adc_joystick_close; + + ret = adc_joystick_set_axes(dev, joy); + if (ret) + return ret; + + input_set_drvdata(input, joy); + ret = input_register_device(input); + if (ret) { + dev_err(dev, "Unable to register input device: %d", ret); + return ret; + } + + joy->buffer = iio_channel_get_all_cb(dev, adc_joystick_handle, joy); + if (IS_ERR(joy->buffer)) { + dev_err(dev, "Unable to allocate callback buffer"); + return PTR_ERR(joy->buffer); + } + + ret = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer); + if (ret) + dev_err(dev, "Unable to add action"); + + return ret; +} + +static const struct of_device_id adc_joystick_of_match[] = { + { .compatible = "adc-joystick", }, + { } +}; +MODULE_DEVICE_TABLE(of, adc_joystick_of_match); + +static struct platform_driver adc_joystick_driver = { + .driver = { + .name = "adc-joystick", + .of_match_table = adc_joystick_of_match, + }, + .probe = adc_joystick_probe, +}; +module_platform_driver(adc_joystick_driver); + +MODULE_DESCRIPTION("Input driver for joysticks connected over ADC"); +MODULE_AUTHOR("Artur Rojek <contact@artur-rojek.eu>"); +MODULE_LICENSE("GPL");