diff mbox series

[v2,2/3] Input: adc-joystick - Add polled input device support

Message ID 20220601204927.10256-3-macroalpha82@gmail.com (mailing list archive)
State Superseded
Headers show
Series adc-joystick: Add polled support | expand

Commit Message

Chris Morgan June 1, 2022, 8:49 p.m. UTC
From: Chris Morgan <macromorgan@hotmail.com>

Add polled input device support to the adc-joystick driver. This is
useful for devices which do not have hardware capable triggers on
their SARADC. Code modified from adc-joystick.c changes made by Maya
Matuszczyk.

Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
---
 drivers/input/joystick/adc-joystick.c | 52 +++++++++++++++++++++------
 1 file changed, 41 insertions(+), 11 deletions(-)

Comments

Dmitry Torokhov June 1, 2022, 10 p.m. UTC | #1
On Wed, Jun 01, 2022 at 03:49:26PM -0500, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add polled input device support to the adc-joystick driver. This is
> useful for devices which do not have hardware capable triggers on
> their SARADC. Code modified from adc-joystick.c changes made by Maya
> Matuszczyk.

I'd like to hear Jonathan's take on this...

> 
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  drivers/input/joystick/adc-joystick.c | 52 +++++++++++++++++++++------
>  1 file changed, 41 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c
> index 78ebca7d400a..5a28fe7b8ebc 100644
> --- a/drivers/input/joystick/adc-joystick.c
> +++ b/drivers/input/joystick/adc-joystick.c
> @@ -13,6 +13,10 @@
>  
>  #include <asm/unaligned.h>
>  
> +#define ADC_JSK_POLL_INTERVAL	16
> +#define ADC_JSK_POLL_MIN	8
> +#define ADC_JSK_POLL_MAX	32
> +
>  struct adc_joystick_axis {
>  	u32 code;
>  	s32 range[2];
> @@ -26,8 +30,21 @@ struct adc_joystick {
>  	struct adc_joystick_axis *axes;
>  	struct iio_channel *chans;
>  	int num_chans;
> +	bool polled;
>  };
>  
> +static void adc_joystick_poll(struct input_dev *input)
> +{
> +	struct adc_joystick *joy = input_get_drvdata(input);
> +	int i, val;
> +
> +	for (i = 0; i < joy->num_chans; i++) {
> +		iio_read_channel_raw(&joy->chans[i], &val);
> +		input_report_abs(input, joy->axes[i].code, val);
> +	}
> +	input_sync(input);
> +}
> +
>  static int adc_joystick_handle(const void *data, void *private)
>  {
>  	struct adc_joystick *joy = private;
> @@ -215,8 +232,19 @@ static int adc_joystick_probe(struct platform_device *pdev)
>  	joy->input = input;
>  	input->name = pdev->name;
>  	input->id.bustype = BUS_HOST;
> -	input->open = adc_joystick_open;
> -	input->close = adc_joystick_close;
> +
> +	if (device_property_read_bool(dev, "adc-joystick,polled"))
> +		joy->polled = 1;
> +
> +	if (joy->polled) {
> +		input_setup_polling(input, adc_joystick_poll);
> +		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
> +		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
> +		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
> +	} else {
> +		input->open = adc_joystick_open;
> +		input->close = adc_joystick_close;
> +	}
>  
>  	error = adc_joystick_set_axes(dev, joy);
>  	if (error)
> @@ -229,16 +257,18 @@ static int adc_joystick_probe(struct platform_device *pdev)
>  		return error;
>  	}
>  
> -	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\n");
> -		return PTR_ERR(joy->buffer);
> -	}
> +	if (!joy->polled) {
> +		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\n");
> +			return PTR_ERR(joy->buffer);
> +		}
>  
> -	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
> -	if (error)  {
> -		dev_err(dev, "Unable to add action\n");
> -		return error;
> +		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
> +		if (error)  {
> +			dev_err(dev, "Unable to add action\n");
> +			return error;
> +		}
>  	}
>  
>  	return 0;
> -- 
> 2.25.1
>
Artur Rojek June 1, 2022, 10:14 p.m. UTC | #2
On 2022-06-01 22:49, Chris Morgan wrote:
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add polled input device support to the adc-joystick driver. This is
> useful for devices which do not have hardware capable triggers on
> their SARADC. Code modified from adc-joystick.c changes made by Maya
> Matuszczyk.
> 
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  drivers/input/joystick/adc-joystick.c | 52 +++++++++++++++++++++------
>  1 file changed, 41 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/input/joystick/adc-joystick.c
> b/drivers/input/joystick/adc-joystick.c
> index 78ebca7d400a..5a28fe7b8ebc 100644
> --- a/drivers/input/joystick/adc-joystick.c
> +++ b/drivers/input/joystick/adc-joystick.c
> @@ -13,6 +13,10 @@
> 
>  #include <asm/unaligned.h>
> 
> +#define ADC_JSK_POLL_INTERVAL	16
> +#define ADC_JSK_POLL_MIN	8
> +#define ADC_JSK_POLL_MAX	32
> +
>  struct adc_joystick_axis {
>  	u32 code;
>  	s32 range[2];
> @@ -26,8 +30,21 @@ struct adc_joystick {
>  	struct adc_joystick_axis *axes;
>  	struct iio_channel *chans;
>  	int num_chans;
> +	bool polled;
>  };
> 
> +static void adc_joystick_poll(struct input_dev *input)
> +{
> +	struct adc_joystick *joy = input_get_drvdata(input);
> +	int i, val;
> +
> +	for (i = 0; i < joy->num_chans; i++) {
> +		iio_read_channel_raw(&joy->chans[i], &val);
> +		input_report_abs(input, joy->axes[i].code, val);
> +	}
> +	input_sync(input);
> +}
> +
>  static int adc_joystick_handle(const void *data, void *private)
>  {
>  	struct adc_joystick *joy = private;
> @@ -215,8 +232,19 @@ static int adc_joystick_probe(struct 
> platform_device *pdev)
>  	joy->input = input;
>  	input->name = pdev->name;
>  	input->id.bustype = BUS_HOST;
> -	input->open = adc_joystick_open;
> -	input->close = adc_joystick_close;
> +
> +	if (device_property_read_bool(dev, "adc-joystick,polled"))
> +		joy->polled = 1;
No need for branching, you can simply do:
	joy->polled = device_property_read_bool(dev, "adc-joystick,polled");

> +
> +	if (joy->polled) {
> +		input_setup_polling(input, adc_joystick_poll);
> +		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
> +		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
> +		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
> +	} else {
> +		input->open = adc_joystick_open;
> +		input->close = adc_joystick_close;
> +	}
> 
>  	error = adc_joystick_set_axes(dev, joy);
>  	if (error)
> @@ -229,16 +257,18 @@ static int adc_joystick_probe(struct
> platform_device *pdev)
>  		return error;
>  	}
> 
> -	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\n");
> -		return PTR_ERR(joy->buffer);
> -	}
> +	if (!joy->polled) {
> +		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\n");
> +			return PTR_ERR(joy->buffer);
> +		}
> 
> -	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> joy->buffer);
> -	if (error)  {
> -		dev_err(dev, "Unable to add action\n");
> -		return error;
> +		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> joy->buffer);
> +		if (error)  {
> +			dev_err(dev, "Unable to add action\n");
> +			return error;
> +		}
>  	}
> 
>  	return 0;
Paul Cercueil June 2, 2022, 9:22 a.m. UTC | #3
Hi Chris,

Le mer., juin 1 2022 at 15:49:26 -0500, Chris Morgan 
<macroalpha82@gmail.com> a écrit :
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add polled input device support to the adc-joystick driver. This is
> useful for devices which do not have hardware capable triggers on
> their SARADC. Code modified from adc-joystick.c changes made by Maya
> Matuszczyk.

I understand what you're trying to do, but maybe there's a better way.

It would be better if pollable IIO devices would also be able to be 
used with a buffer, with the client driver manually triggering the IIO 
device through a function call.

Jonathan (Cc'd) might have his reasons why this isn't done this way, 
and in this case your patch makes sense, but I'd like to hear 
Jonathan's thoughts first.

As for "adc-joystick,polled"... it doesn't describe the hardware but 
rather a specific configuration, so it shouldn't appear in the device 
tree.

Cheers,
-Paul

> 
> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  drivers/input/joystick/adc-joystick.c | 52 
> +++++++++++++++++++++------
>  1 file changed, 41 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/input/joystick/adc-joystick.c 
> b/drivers/input/joystick/adc-joystick.c
> index 78ebca7d400a..5a28fe7b8ebc 100644
> --- a/drivers/input/joystick/adc-joystick.c
> +++ b/drivers/input/joystick/adc-joystick.c
> @@ -13,6 +13,10 @@
> 
>  #include <asm/unaligned.h>
> 
> +#define ADC_JSK_POLL_INTERVAL	16
> +#define ADC_JSK_POLL_MIN	8
> +#define ADC_JSK_POLL_MAX	32
> +
>  struct adc_joystick_axis {
>  	u32 code;
>  	s32 range[2];
> @@ -26,8 +30,21 @@ struct adc_joystick {
>  	struct adc_joystick_axis *axes;
>  	struct iio_channel *chans;
>  	int num_chans;
> +	bool polled;
>  };
> 
> +static void adc_joystick_poll(struct input_dev *input)
> +{
> +	struct adc_joystick *joy = input_get_drvdata(input);
> +	int i, val;
> +
> +	for (i = 0; i < joy->num_chans; i++) {
> +		iio_read_channel_raw(&joy->chans[i], &val);
> +		input_report_abs(input, joy->axes[i].code, val);
> +	}
> +	input_sync(input);
> +}
> +
>  static int adc_joystick_handle(const void *data, void *private)
>  {
>  	struct adc_joystick *joy = private;
> @@ -215,8 +232,19 @@ static int adc_joystick_probe(struct 
> platform_device *pdev)
>  	joy->input = input;
>  	input->name = pdev->name;
>  	input->id.bustype = BUS_HOST;
> -	input->open = adc_joystick_open;
> -	input->close = adc_joystick_close;
> +
> +	if (device_property_read_bool(dev, "adc-joystick,polled"))
> +		joy->polled = 1;
> +
> +	if (joy->polled) {
> +		input_setup_polling(input, adc_joystick_poll);
> +		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
> +		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
> +		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
> +	} else {
> +		input->open = adc_joystick_open;
> +		input->close = adc_joystick_close;
> +	}
> 
>  	error = adc_joystick_set_axes(dev, joy);
>  	if (error)
> @@ -229,16 +257,18 @@ static int adc_joystick_probe(struct 
> platform_device *pdev)
>  		return error;
>  	}
> 
> -	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\n");
> -		return PTR_ERR(joy->buffer);
> -	}
> +	if (!joy->polled) {
> +		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\n");
> +			return PTR_ERR(joy->buffer);
> +		}
> 
> -	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> joy->buffer);
> -	if (error)  {
> -		dev_err(dev, "Unable to add action\n");
> -		return error;
> +		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> joy->buffer);
> +		if (error)  {
> +			dev_err(dev, "Unable to add action\n");
> +			return error;
> +		}
>  	}
> 
>  	return 0;
Heiko Stübner June 2, 2022, 11:01 a.m. UTC | #4
Am Mittwoch, 1. Juni 2022, 22:49:26 CEST schrieb Chris Morgan:
> From: Chris Morgan <macromorgan@hotmail.com>
> 
> Add polled input device support to the adc-joystick driver. This is
> useful for devices which do not have hardware capable triggers on
> their SARADC. Code modified from adc-joystick.c changes made by Maya
> Matuszczyk.

as the dts patch mentiones the odroid go2, this probably means the
Rockchip-saradc?

I very much remember that we converted the saradc to also support
triggered buffers [0] two years ago, and as I remember that worked
rather nicely on the Go-1 at least - similar hardware I think.

So it would be really helpful to provide some more explanation on
why this isn't enough for your use-case.


[0] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=4e130dc7b41348b13684f0758c26cc6cf72a3449


> Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> ---
>  drivers/input/joystick/adc-joystick.c | 52 +++++++++++++++++++++------
>  1 file changed, 41 insertions(+), 11 deletions(-)
> 
> diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c
> index 78ebca7d400a..5a28fe7b8ebc 100644
> --- a/drivers/input/joystick/adc-joystick.c
> +++ b/drivers/input/joystick/adc-joystick.c
> @@ -13,6 +13,10 @@
>  
>  #include <asm/unaligned.h>
>  
> +#define ADC_JSK_POLL_INTERVAL	16
> +#define ADC_JSK_POLL_MIN	8
> +#define ADC_JSK_POLL_MAX	32
> +
>  struct adc_joystick_axis {
>  	u32 code;
>  	s32 range[2];
> @@ -26,8 +30,21 @@ struct adc_joystick {
>  	struct adc_joystick_axis *axes;
>  	struct iio_channel *chans;
>  	int num_chans;
> +	bool polled;
>  };
>  
> +static void adc_joystick_poll(struct input_dev *input)
> +{
> +	struct adc_joystick *joy = input_get_drvdata(input);
> +	int i, val;
> +
> +	for (i = 0; i < joy->num_chans; i++) {
> +		iio_read_channel_raw(&joy->chans[i], &val);
> +		input_report_abs(input, joy->axes[i].code, val);
> +	}
> +	input_sync(input);
> +}
> +
>  static int adc_joystick_handle(const void *data, void *private)
>  {
>  	struct adc_joystick *joy = private;
> @@ -215,8 +232,19 @@ static int adc_joystick_probe(struct platform_device *pdev)
>  	joy->input = input;
>  	input->name = pdev->name;
>  	input->id.bustype = BUS_HOST;
> -	input->open = adc_joystick_open;
> -	input->close = adc_joystick_close;
> +
> +	if (device_property_read_bool(dev, "adc-joystick,polled"))
> +		joy->polled = 1;
> +
> +	if (joy->polled) {
> +		input_setup_polling(input, adc_joystick_poll);
> +		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
> +		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
> +		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
> +	} else {
> +		input->open = adc_joystick_open;
> +		input->close = adc_joystick_close;
> +	}
>  
>  	error = adc_joystick_set_axes(dev, joy);
>  	if (error)
> @@ -229,16 +257,18 @@ static int adc_joystick_probe(struct platform_device *pdev)
>  		return error;
>  	}
>  
> -	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\n");
> -		return PTR_ERR(joy->buffer);
> -	}
> +	if (!joy->polled) {
> +		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\n");
> +			return PTR_ERR(joy->buffer);
> +		}
>  
> -	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
> -	if (error)  {
> -		dev_err(dev, "Unable to add action\n");
> -		return error;
> +		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
> +		if (error)  {
> +			dev_err(dev, "Unable to add action\n");
> +			return error;
> +		}
>  	}
>  
>  	return 0;
>
Jonathan Cameron June 19, 2022, 3:17 p.m. UTC | #5
On Thu, 02 Jun 2022 10:22:11 +0100
Paul Cercueil <paul@crapouillou.net> wrote:

> Hi Chris,
> 
> Le mer., juin 1 2022 at 15:49:26 -0500, Chris Morgan 
> <macroalpha82@gmail.com> a écrit :
> > From: Chris Morgan <macromorgan@hotmail.com>
> > 
> > Add polled input device support to the adc-joystick driver. This is
> > useful for devices which do not have hardware capable triggers on
> > their SARADC. Code modified from adc-joystick.c changes made by Maya
> > Matuszczyk.  
> 
> I understand what you're trying to do, but maybe there's a better way.
> 
> It would be better if pollable IIO devices would also be able to be 
> used with a buffer, with the client driver manually triggering the IIO 
> device through a function call.

We've done exactly that in the past for some of the weirder consumer
drivers.  Though it's done by hooking up a trigger that is provided
by the channel consumer to the supplier device.

> 
> Jonathan (Cc'd) might have his reasons why this isn't done this way, 
> and in this case your patch makes sense, but I'd like to hear 
> Jonathan's thoughts first.

It rarely makes sense to have a sysfs only ADC and it's usually trivial
to add basic support for buffered mode to use with a trigger from elsewhere.
It's rare that their aren't optimizations around batching etc that
make sense though in this path and not the sysfs polling path where only
one channel is being read.   Hence it's not worth a generic route to
hooking them together.

> 
> As for "adc-joystick,polled"... it doesn't describe the hardware but 
> rather a specific configuration, so it shouldn't appear in the device 
> tree.

Sorry, got lost in my email.

I'll take a look at v3.

Jonathan

> 
> Cheers,
> -Paul
> 
> > 
> > Signed-off-by: Maya Matuszczyk <maccraft123mc@gmail.com>
> > Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
> > ---
> >  drivers/input/joystick/adc-joystick.c | 52 
> > +++++++++++++++++++++------
> >  1 file changed, 41 insertions(+), 11 deletions(-)
> > 
> > diff --git a/drivers/input/joystick/adc-joystick.c 
> > b/drivers/input/joystick/adc-joystick.c
> > index 78ebca7d400a..5a28fe7b8ebc 100644
> > --- a/drivers/input/joystick/adc-joystick.c
> > +++ b/drivers/input/joystick/adc-joystick.c
> > @@ -13,6 +13,10 @@
> > 
> >  #include <asm/unaligned.h>
> > 
> > +#define ADC_JSK_POLL_INTERVAL	16
> > +#define ADC_JSK_POLL_MIN	8
> > +#define ADC_JSK_POLL_MAX	32
> > +
> >  struct adc_joystick_axis {
> >  	u32 code;
> >  	s32 range[2];
> > @@ -26,8 +30,21 @@ struct adc_joystick {
> >  	struct adc_joystick_axis *axes;
> >  	struct iio_channel *chans;
> >  	int num_chans;
> > +	bool polled;
> >  };
> > 
> > +static void adc_joystick_poll(struct input_dev *input)
> > +{
> > +	struct adc_joystick *joy = input_get_drvdata(input);
> > +	int i, val;
> > +
> > +	for (i = 0; i < joy->num_chans; i++) {
> > +		iio_read_channel_raw(&joy->chans[i], &val);
> > +		input_report_abs(input, joy->axes[i].code, val);
> > +	}
> > +	input_sync(input);
> > +}
> > +
> >  static int adc_joystick_handle(const void *data, void *private)
> >  {
> >  	struct adc_joystick *joy = private;
> > @@ -215,8 +232,19 @@ static int adc_joystick_probe(struct 
> > platform_device *pdev)
> >  	joy->input = input;
> >  	input->name = pdev->name;
> >  	input->id.bustype = BUS_HOST;
> > -	input->open = adc_joystick_open;
> > -	input->close = adc_joystick_close;
> > +
> > +	if (device_property_read_bool(dev, "adc-joystick,polled"))
> > +		joy->polled = 1;
> > +
> > +	if (joy->polled) {
> > +		input_setup_polling(input, adc_joystick_poll);
> > +		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
> > +		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
> > +		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
> > +	} else {
> > +		input->open = adc_joystick_open;
> > +		input->close = adc_joystick_close;
> > +	}
> > 
> >  	error = adc_joystick_set_axes(dev, joy);
> >  	if (error)
> > @@ -229,16 +257,18 @@ static int adc_joystick_probe(struct 
> > platform_device *pdev)
> >  		return error;
> >  	}
> > 
> > -	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\n");
> > -		return PTR_ERR(joy->buffer);
> > -	}
> > +	if (!joy->polled) {
> > +		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\n");
> > +			return PTR_ERR(joy->buffer);
> > +		}
> > 
> > -	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> > joy->buffer);
> > -	if (error)  {
> > -		dev_err(dev, "Unable to add action\n");
> > -		return error;
> > +		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, 
> > joy->buffer);
> > +		if (error)  {
> > +			dev_err(dev, "Unable to add action\n");
> > +			return error;
> > +		}
> >  	}
> > 
> >  	return 0;  
> 
>
diff mbox series

Patch

diff --git a/drivers/input/joystick/adc-joystick.c b/drivers/input/joystick/adc-joystick.c
index 78ebca7d400a..5a28fe7b8ebc 100644
--- a/drivers/input/joystick/adc-joystick.c
+++ b/drivers/input/joystick/adc-joystick.c
@@ -13,6 +13,10 @@ 
 
 #include <asm/unaligned.h>
 
+#define ADC_JSK_POLL_INTERVAL	16
+#define ADC_JSK_POLL_MIN	8
+#define ADC_JSK_POLL_MAX	32
+
 struct adc_joystick_axis {
 	u32 code;
 	s32 range[2];
@@ -26,8 +30,21 @@  struct adc_joystick {
 	struct adc_joystick_axis *axes;
 	struct iio_channel *chans;
 	int num_chans;
+	bool polled;
 };
 
+static void adc_joystick_poll(struct input_dev *input)
+{
+	struct adc_joystick *joy = input_get_drvdata(input);
+	int i, val;
+
+	for (i = 0; i < joy->num_chans; i++) {
+		iio_read_channel_raw(&joy->chans[i], &val);
+		input_report_abs(input, joy->axes[i].code, val);
+	}
+	input_sync(input);
+}
+
 static int adc_joystick_handle(const void *data, void *private)
 {
 	struct adc_joystick *joy = private;
@@ -215,8 +232,19 @@  static int adc_joystick_probe(struct platform_device *pdev)
 	joy->input = input;
 	input->name = pdev->name;
 	input->id.bustype = BUS_HOST;
-	input->open = adc_joystick_open;
-	input->close = adc_joystick_close;
+
+	if (device_property_read_bool(dev, "adc-joystick,polled"))
+		joy->polled = 1;
+
+	if (joy->polled) {
+		input_setup_polling(input, adc_joystick_poll);
+		input_set_poll_interval(input, ADC_JSK_POLL_INTERVAL);
+		input_set_min_poll_interval(input, ADC_JSK_POLL_MIN);
+		input_set_max_poll_interval(input, ADC_JSK_POLL_MAX);
+	} else {
+		input->open = adc_joystick_open;
+		input->close = adc_joystick_close;
+	}
 
 	error = adc_joystick_set_axes(dev, joy);
 	if (error)
@@ -229,16 +257,18 @@  static int adc_joystick_probe(struct platform_device *pdev)
 		return error;
 	}
 
-	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\n");
-		return PTR_ERR(joy->buffer);
-	}
+	if (!joy->polled) {
+		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\n");
+			return PTR_ERR(joy->buffer);
+		}
 
-	error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
-	if (error)  {
-		dev_err(dev, "Unable to add action\n");
-		return error;
+		error = devm_add_action_or_reset(dev, adc_joystick_cleanup, joy->buffer);
+		if (error)  {
+			dev_err(dev, "Unable to add action\n");
+			return error;
+		}
 	}
 
 	return 0;