Re: [PATCH v3 3/3] input: pwm-beeper: add devicetree bindings to set volume levels

[Frieder Schrempf <frieder.schrempf@exceet.de>]

On 19.01.2017 22:30, Dmitry Torokhov wrote:
> On Thu, Jan 19, 2017 at 04:24:10PM +0100, Frieder Schrempf wrote:
>> This patch adds the devicetree bindings to set the volume levels
>> and the default volume level.
>>
>> Signed-off-by: Frieder Schrempf <frieder.schrempf@exceet.de>
>> ---
>> Changes in v3:
>>  - none
>>
>>  drivers/input/misc/pwm-beeper.c | 49 ++++++++++++++++++++++++++++++++++++++---
>>  1 file changed, 46 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/input/misc/pwm-beeper.c b/drivers/input/misc/pwm-beeper.c
>> index 3ed21da..a7f9d70 100644
>> --- a/drivers/input/misc/pwm-beeper.c
>> +++ b/drivers/input/misc/pwm-beeper.c
>> @@ -32,7 +32,7 @@ struct pwm_beeper {
>>  	struct work_struct work;
>>  	unsigned long period;
>>  	unsigned int volume;
>> -	unsigned int volume_levels[] = {0, 8, 20, 40, 500};
>> +	unsigned int *volume_levels;
>>  	unsigned int max_volume_level;
>>  };
>>
>> @@ -161,8 +161,11 @@ static void pwm_beeper_close(struct input_dev *input)
>>  static int pwm_beeper_probe(struct platform_device *pdev)
>>  {
>>  	unsigned long pwm_id = (unsigned long)dev_get_platdata(&pdev->dev);
>> +	struct device_node *np = pdev->dev.of_node;
>>  	struct pwm_beeper *beeper;
>> -	int error;
>> +	struct property *prop;
>> +	int error, length;
>> +	u32 value;
>>
>>  	beeper = kzalloc(sizeof(*beeper), GFP_KERNEL);
>>  	if (!beeper)
>> @@ -188,7 +191,47 @@ static int pwm_beeper_probe(struct platform_device *pdev)
>>
>>  	INIT_WORK(&beeper->work, pwm_beeper_work);
>>
>> -	beeper->max_volume_level = ARRAY_SIZE(beeper->volume_levels) - 1;
>> +	/* determine the number of volume levels */
>> +	prop = of_find_property(np, "volume-levels", &length);
>
> Please use generic device properties, not OF-specific ones.

Ok, I will change this in v4.
>
>> +	if (!prop) {
>> +		dev_dbg(&pdev->dev, "no volume levels specified, using max volume\n");
>> +		beeper->max_volume_level = 1;
>> +	} else
>> +		beeper->max_volume_level = length / sizeof(u32);
>> +
>> +	/* read volume levels from DT property */
>> +	if (beeper->max_volume_level > 0) {
>> +		size_t size = sizeof(*beeper->volume_levels) *
>> +			beeper->max_volume_level;
>> +
>> +		beeper->volume_levels = devm_kzalloc(&(pdev->dev), size,
>> +			GFP_KERNEL);
>> +		if (!beeper->volume_levels)
>> +			return -ENOMEM;
>> +
>> +		if (prop) {
>> +			error = of_property_read_u32_array(np, "volume-levels",
>> +						beeper->volume_levels,
>> +						beeper->max_volume_level);
>> +
>> +			if (error < 0)
>> +				return error;
>> +
>> +			error = of_property_read_u32(np, "default-volume-level",
>> +						   &value);
>> +
>> +			if (error < 0) {
>> +				dev_dbg(&pdev->dev, "no default volume specified, using max volume\n");
>> +				value = beeper->max_volume_level - 1;
>> +			}
>> +		} else {
>> +			beeper->volume_levels[0] = 500;
>> +			value = 0;
>> +		}
>> +
>> +		beeper->volume = value;
>> +		beeper->max_volume_level--;
>> +	}
>>
>>  	beeper->input = input_allocate_device();
>>  	if (!beeper->input) {
>> --
>> 2.7.4
>>
>