Re: [PATCH 3/3] staging:iio: Proof of concept input driver.

[Jonathan Cameron <jic23@kernel.org>]

On 03/04/2012 04:11 PM, Dmitry Torokhov wrote:
> Hi Jonathan,
> 
> On Sat, Mar 03, 2012 at 12:09:11PM +0000, Jonathan Cameron wrote:
>> From: Jonathan Cameron <jic23@cam.ac.uk>
>>
>> This is no where near ready to merge.  Lots of stuff missing.
>>
>> Signed-off-by: Jonathan Cameron <jic23@kernel.org>
>> ---
>>  drivers/staging/iio/Kconfig     |   10 ++++
>>  drivers/staging/iio/Makefile    |    1 +
>>  drivers/staging/iio/iio_input.c |  106 +++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 117 insertions(+)
>>
>> diff --git a/drivers/staging/iio/Kconfig b/drivers/staging/iio/Kconfig
>> index 4aff125..a599f16 100644
>> --- a/drivers/staging/iio/Kconfig
>> +++ b/drivers/staging/iio/Kconfig
>> @@ -11,6 +11,16 @@ menuconfig IIO
>>  	  number of different physical interfaces (i2c, spi, etc). See
>>  	  drivers/staging/iio/Documentation for more information.
>>  if IIO
>> +
>> +config IIO_ST_INPUT
>> +	tristate "Input driver that uses channels specified via iio maps"
>> +	depends on INPUT
>> +	depends on IIO_BUFFER
>> +	select IIO_BUFFER_CB
>> +	help
>> +	  Proof of concept user of the in kernel push interface.  Not anywhere
>> +	  near ready for production use.
>> +
>>  config IIO_ST_HWMON
>>  	tristate "Hwmon driver that uses channels specified via iio maps"
>>  	depends on HWMON
>> diff --git a/drivers/staging/iio/Makefile b/drivers/staging/iio/Makefile
>> index f55de94..f64c93b 100644
>> --- a/drivers/staging/iio/Makefile
>> +++ b/drivers/staging/iio/Makefile
>> @@ -19,6 +19,7 @@ iio_dummy-$(CONFIG_IIO_SIMPLE_DUMMY_BUFFER) += iio_simple_dummy_buffer.o
>>  obj-$(CONFIG_IIO_DUMMY_EVGEN) += iio_dummy_evgen.o
>>  
>>  obj-$(CONFIG_IIO_ST_HWMON) += iio_hwmon.o
>> +obj-$(CONFIG_IIO_ST_INPUT) += iio_input.o
>>  
>>  obj-y += accel/
>>  obj-y += adc/
>> diff --git a/drivers/staging/iio/iio_input.c b/drivers/staging/iio/iio_input.c
>> new file mode 100644
>> index 0000000..2481901
>> --- /dev/null
>> +++ b/drivers/staging/iio/iio_input.c
>> @@ -0,0 +1,106 @@
>> +#include <linux/kernel.h>
>> +#include <linux/slab.h>
>> +#include <linux/module.h>
>> +#include <linux/err.h>
>> +#include <linux/platform_device.h>
>> +#include <linux/input.h>
>> +#include "buffer.h"
>> +#include "consumer.h"
>> +
>> +struct iio_input_state {
>> +	struct iio_cb_buffer *buff;
>> +	struct input_dev *idev;
>> +};
>> +
>> +static int iio_input_store_to(u8 *data, void *private)
>> +{
>> +	struct iio_input_state *st = private;
>> +
>> +	/* DUMMY - need to put boiler plate conversion code
>> +	 * in place */
>> +	input_report_abs(st->idev, ABS_X, data[0]);
>> +	input_sync(st->idev);
>> +
>> +	return 0;
>> +}
>> +
>> +static int __devinit iio_input_probe(struct platform_device *pdev)
>> +{
>> +	struct iio_input_state *st;
>> +	int ret;
>> +
>> +	st = kzalloc(sizeof(*st), GFP_KERNEL);
>> +	if (st == NULL)
>> +		return -ENOMEM;
>> +	platform_set_drvdata(pdev, st);
>> +	st->buff = iio_st_channel_get_all_cb(dev_name(&pdev->dev),
>> +					     &iio_input_store_to,
>> +					     st);
>> +	if (IS_ERR(st->buff)) {
>> +		ret = PTR_ERR(st->buff);
>> +		goto error_free_state;
>> +	}
>> +
>> +	st->idev = input_allocate_device();
>> +	if (!st->idev) {
>> +		ret = -ENOMEM;
>> +		goto error_channels_release_all;
>> +	}
>> +
>> +	__set_bit(EV_ABS, st->idev->evbit);
>> +	/* DUMMY DATA - need to actually make this available */
>> +	input_set_abs_params(st->idev, ABS_X, 0, 100, 0, 0);
>> +
>> +	ret = input_register_device(st->idev);
>> +	if (ret < 0)
>> +		goto error_free_idev;
>> +
>> +	/* NORMALLY IN THE OPEN */
>> +	iio_st_channel_start_all_cb(st->buff);
>> +
>> +	return 0;
>> +error_free_idev:
>> +	input_free_device(st->idev);
>> +error_channels_release_all:
>> +	iio_st_channel_release_all_cb(st->buff);
>> +error_free_state:
>> +	kfree(st);
>> +	return ret;
>> +}
>> +
>> +static int __devexit iio_input_remove(struct platform_device *pdev)
>> +{
>> +	struct iio_input_state *st = platform_get_drvdata(pdev);
>> +	/* NORMALLY IN THE CLOSE */
>> +	iio_st_channel_stop_all_cb(st->buff);
>> +	input_unregister_device(st->idev);
>> +	iio_st_channel_release_all_cb(st->buff);
>> +
>> +	kfree(st);
>> +	return 0;
>> +}
>> +
>> +static struct platform_driver __refdata iio_input_driver = {
> 
> Why is this __refdata?
No idea :)  Will drop that.  Also can use the platform_device_module
stuff below to get rid of some of this boiler plate.

Will clear all this up for a version that actually does something
beyond the proof of concept here!

Thanks for taking a look,

Jonathan
> 
>> +	.driver = {
>> +		.name = "iio_snoop",
>> +		.owner = THIS_MODULE,
>> +	},
>> +	.probe = iio_input_probe,
>> +	.remove = __devexit_p(iio_input_remove),
>> +};
>> +
>> +static int iio_input_init(void)
> 
> __init
> 
>> +{
>> +	return platform_driver_register(&iio_input_driver);
>> +}
>> +module_init(iio_input_init);
>> +
>> +static void iio_input_exit(void)
> 
> __exit
good point. Thanks!
> 
>> +{
>> +	platform_driver_unregister(&iio_input_driver);
>> +}
>> +module_exit(iio_input_exit);
>> +
>> +MODULE_AUTHOR("Jonathan Cameron <jic23@cam.ac.uk>");
>> +MODULE_DESCRIPTION("IIO input buffer driver");
>> +MODULE_LICENSE("GPL v2");
>> -- 
>> 1.7.9.2
>>
> 
> Thanks.
>