[PATCH 5/6] ARM: s3c64xx: hmt: Use PWM lookup table

Thierry Reding thierry.reding at gmail.com
Wed Oct 7 08:37:24 PDT 2015


On Wed, Oct 07, 2015 at 10:37:42AM +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-s3c64xx/mach-hmt.c | 9 +++++++--
> >  1 file changed, 7 insertions(+), 2 deletions(-)
> > 
> > diff --git a/arch/arm/mach-s3c64xx/mach-hmt.c b/arch/arm/mach-s3c64xx/mach-hmt.c
> > index e4b087c58ee6..816b39d1e6d1 100644
> > --- a/arch/arm/mach-s3c64xx/mach-hmt.c
> > +++ b/arch/arm/mach-s3c64xx/mach-hmt.c
> > @@ -19,6 +19,7 @@
> >  #include <linux/gpio.h>
> >  #include <linux/delay.h>
> >  #include <linux/leds.h>
> > +#include <linux/pwm.h>
> >  #include <linux/pwm_backlight.h>
> >  #include <linux/mtd/mtd.h>
> >  #include <linux/mtd/partitions.h>
> > @@ -73,6 +74,11 @@ static struct s3c2410_uartcfg hmt_uartcfgs[] __initdata = {
> >  	},
> >  };
> >  
> > +static struct pwm_lookup hmt_pwm_lookup[] = {
> > +	PWM_LOOKUP("samsung-pwm", 1, "pwm-backlight.0", NULL,
> 
> Same questions as in patch 2 - why suffix ".0" for "pwm-backlight"?

For the same reason that I explained in patch 2. Not sure if the .id = 0
was really supposed to be. For most devices it would probably make sense
to initialize it to -1 because they typically only have a single
backlight. But given that userspace might be using the name to control
the backlight via sysfs it's probably not a good idea to go and change
that.

Thierry
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: not available
URL: <http://lists.infradead.org/pipermail/linux-arm-kernel/attachments/20151007/0a97cee3/attachment-0001.sig>


More information about the linux-arm-kernel mailing list