[PATCH 2/6] ARM: s3c24xx: rx1950: Use PWM lookup table
Krzysztof Kozlowski
k.kozlowski at samsung.com
Wed Oct 7 18:00:23 PDT 2015
On 08.10.2015 00:31, Thierry Reding wrote:
> On Wed, Oct 07, 2015 at 10:35:54AM +0900, Krzysztof Kozlowski wrote:
>> On 05.10.2015 21:47, Thierry Reding wrote:
>>> Use a PWM lookup table to provide the PWM to the pwm-backlight device.
>>> The driver has a legacy code path that is required only because boards
>>> still use the legacy method of requesting PWMs by global ID. Replacing
>>> these usages allows that legacy fallback to be removed.
>>>
>>> Cc: Kukjin Kim <kgene at kernel.org>
>>> Cc: Krzysztof Kozlowski <k.kozlowski at samsung.com>
>>> Signed-off-by: Thierry Reding <thierry.reding at gmail.com>
>>> ---
>>> arch/arm/mach-s3c24xx/mach-rx1950.c | 8 ++++++--
>>> 1 file changed, 6 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/arch/arm/mach-s3c24xx/mach-rx1950.c b/arch/arm/mach-s3c24xx/mach-rx1950.c
>>> index 1d35ff375a01..774c982a7b7e 100644
>>> --- a/arch/arm/mach-s3c24xx/mach-rx1950.c
>>> +++ b/arch/arm/mach-s3c24xx/mach-rx1950.c
>>> @@ -375,6 +375,11 @@ static struct s3c2410fb_mach_info rx1950_lcd_cfg = {
>>>
>>> };
>>>
>>> +static struct pwm_lookup rx1950_pwm_lookup[] = {
>>> + PWM_LOOKUP("samsung-pwm", 0, "pwm-backlight.0", NULL, 48000,
>>
>> Why the dev_id is "pwm-backlight.0"? Created platform device name is
>> "pwm-backlight".
>
> "pwm-backlight" is only the base name. The platform bus code will use
> the platform_device.id field and append it to the name as .<id> unless
> it is -1 in which case it will be skipped. So in the rx1950_backlight
> device the .id field isn't initialized at all, so it will be zeroed
> out and hence the device name will become "pwm-backlight.0".
Right, I missed the difference in device id.
The patch is fine:
Reviewed-by: Krzysztof Kozlowski <k.kozlowski at samsung.com>
Best regards,
Krzysztof
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