| Message ID | 20200126161236.63631-5-contact@artur-rojek.eu (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | [v2,1/5] IIO: Ingenic JZ47xx: Add xlate cb to retrieve correct channel idx | expand |
On Sun, 26 Jan 2020 17:12:36 +0100 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> > Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> This also looks good to me. Just that dt patch to tidy up. Thanks, 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 > > drivers/input/joystick/Kconfig | 10 ++ > drivers/input/joystick/Makefile | 1 + > drivers/input/joystick/adc-joystick.c | 245 ++++++++++++++++++++++++++ > 3 files changed, 256 insertions(+) > create mode 100644 drivers/input/joystick/adc-joystick.c > > diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig > index 940b744639c7..efbc20ec5099 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..9cb9896da26e > --- /dev/null > +++ b/drivers/input/joystick/adc-joystick.c > @@ -0,0 +1,245 @@ > +// 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/of.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, i; > + bool sign; > + > + bytes = joy->chans[0].channel->scan_type.storagebits >> 3; > + > + for (i = 0; i < joy->num_chans; ++i) { > + 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)[i]; > + break; > + case 2: > + val = ((const u16 *)data)[i]; > + if (endianness == IIO_BE) > + val = be16_to_cpu(val); > + else if (endianness == IIO_LE) > + val = le16_to_cpu(val); > + 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 || i >= num_axes) { > + dev_err(dev, "reg invalid or missing"); > + goto err; > + } > + > + if (fwnode_property_read_u32(child, "linux,code", > + &axes[i].code)) { > + dev_err(dev, "linux,code invalid or missing"); > + goto err; > + } > + > + if (fwnode_property_read_u32_array(child, "abs-range", > + axes[i].range, 2)) { > + 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 -EINVAL; > +} > + > +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. */ > + while (joy->chans[joy->num_chans].indio_dev) > + joy->num_chans++; > + > + bits = joy->chans[0].channel->scan_type.storagebits; > + if (!bits || (bits >> 3) > 2) { > + dev_err(dev, "Unsupported channel storage size"); > + return -EINVAL; > + } > + for (i = 1; i < joy->num_chans; ++i) > + if (joy->chans[i].channel->scan_type.storagebits != bits) { > + dev_err(dev, "Channels must have equal storage size"); > + return -EINVAL; > + } > + > + 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 = of_match_ptr(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");
Hi Jonathan, Rob, The DT check does succeed here, as long as patch [2/5] is applied. I believe Rob's automated test does not apply all patches and that's why it fails here, as the DTS example includes a file that is added in patch 2/5. -Paul Le dim., févr. 2, 2020 at 14:58, Jonathan Cameron <jic23@jic23.retrosnub.co.uk> a écrit : > On Sun, 26 Jan 2020 17:12:36 +0100 > 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> >> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> > > This also looks good to me. Just that dt patch to tidy up. > > Thanks, > > 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 >> >> drivers/input/joystick/Kconfig | 10 ++ >> drivers/input/joystick/Makefile | 1 + >> drivers/input/joystick/adc-joystick.c | 245 >> ++++++++++++++++++++++++++ >> 3 files changed, 256 insertions(+) >> create mode 100644 drivers/input/joystick/adc-joystick.c >> >> diff --git a/drivers/input/joystick/Kconfig >> b/drivers/input/joystick/Kconfig >> index 940b744639c7..efbc20ec5099 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..9cb9896da26e >> --- /dev/null >> +++ b/drivers/input/joystick/adc-joystick.c >> @@ -0,0 +1,245 @@ >> +// 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/of.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, i; >> + bool sign; >> + >> + bytes = joy->chans[0].channel->scan_type.storagebits >> 3; >> + >> + for (i = 0; i < joy->num_chans; ++i) { >> + 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)[i]; >> + break; >> + case 2: >> + val = ((const u16 *)data)[i]; >> + if (endianness == IIO_BE) >> + val = be16_to_cpu(val); >> + else if (endianness == IIO_LE) >> + val = le16_to_cpu(val); >> + 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 || i >= num_axes) { >> + dev_err(dev, "reg invalid or missing"); >> + goto err; >> + } >> + >> + if (fwnode_property_read_u32(child, "linux,code", >> + &axes[i].code)) { >> + dev_err(dev, "linux,code invalid or missing"); >> + goto err; >> + } >> + >> + if (fwnode_property_read_u32_array(child, "abs-range", >> + axes[i].range, 2)) { >> + 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 -EINVAL; >> +} >> + >> +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. */ >> + while (joy->chans[joy->num_chans].indio_dev) >> + joy->num_chans++; >> + >> + bits = joy->chans[0].channel->scan_type.storagebits; >> + if (!bits || (bits >> 3) > 2) { >> + dev_err(dev, "Unsupported channel storage size"); >> + return -EINVAL; >> + } >> + for (i = 1; i < joy->num_chans; ++i) >> + if (joy->chans[i].channel->scan_type.storagebits != bits) { >> + dev_err(dev, "Channels must have equal storage size"); >> + return -EINVAL; >> + } >> + >> + 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 = of_match_ptr(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"); >
Am Sonntag, 26. Januar 2020, 17:12:36 CET schrieb Artur Rojek: > 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> > Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> On a rk3326-based Odroid Go Advance Tested-by: Heiko Stuebner <heiko@sntech.de> would be cool to get this merged ;-) Thanks Heiko
diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig index 940b744639c7..efbc20ec5099 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..9cb9896da26e --- /dev/null +++ b/drivers/input/joystick/adc-joystick.c @@ -0,0 +1,245 @@ +// 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/of.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, i; + bool sign; + + bytes = joy->chans[0].channel->scan_type.storagebits >> 3; + + for (i = 0; i < joy->num_chans; ++i) { + 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)[i]; + break; + case 2: + val = ((const u16 *)data)[i]; + if (endianness == IIO_BE) + val = be16_to_cpu(val); + else if (endianness == IIO_LE) + val = le16_to_cpu(val); + 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 || i >= num_axes) { + dev_err(dev, "reg invalid or missing"); + goto err; + } + + if (fwnode_property_read_u32(child, "linux,code", + &axes[i].code)) { + dev_err(dev, "linux,code invalid or missing"); + goto err; + } + + if (fwnode_property_read_u32_array(child, "abs-range", + axes[i].range, 2)) { + 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 -EINVAL; +} + +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. */ + while (joy->chans[joy->num_chans].indio_dev) + joy->num_chans++; + + bits = joy->chans[0].channel->scan_type.storagebits; + if (!bits || (bits >> 3) > 2) { + dev_err(dev, "Unsupported channel storage size"); + return -EINVAL; + } + for (i = 1; i < joy->num_chans; ++i) + if (joy->chans[i].channel->scan_type.storagebits != bits) { + dev_err(dev, "Channels must have equal storage size"); + return -EINVAL; + } + + 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 = of_match_ptr(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");