[PATCH] ARM: pxa: hx4700: Fix backlight PWM device number

[Paul Parsons]

Hello Thierry,

On 26/09/12 07:03, Thierry Reding wrote:
> On Wed, Sep 26, 2012 at 03:15:06AM +0100, Paul Parsons wrote:
>> Recent changes to PXA PWM support changed the PXA27X PWM device
>> numbering scheme.
>>
>> The linux-3.5 PXA PWM driver followed the hardware numbering scheme for
>> the 4 PWMs, while the linux-3.6-rc1 PXA PWM driver has adopted a linear
>> numbering scheme:
>>
>> Address		Hardware	3.5 pwm_id	3.6-rc1 pwm_id
>> 0x40b00000	PWM0		0		0
>> 0x40b00010	PWM2		2		1
>> 0x40c00000	PWM1		1		2
>> 0x40c00010	PWM3		3		3
>>
>> The hx4700 backlight uses PWM1 at 0x40c00000. Consequently the pwm_id
>> must be changed from 1 to 2.
>>
>> Signed-off-by: Paul Parsons <lost.distance at yahoo.com>
>> Cc: Thierry Reding <thierry.reding at avionic-design.de>
>> ---
>>   arch/arm/mach-pxa/hx4700.c |    2 +-
>>   1 files changed, 1 insertions(+), 1 deletions(-)
>
> I wasn't aware of this difference. Sorry for breaking your board. While
> at it, would you mind converting this to the new style PWM lookup table?
>
> You can find the information in Documentation/pwm.txt, but it should be
> roughly something like this:
>
> 	static struct pwm_lookup hx4700_pwm_lookup[] = {
> 		PWM_LOOKUP("pxa27x-pwm.1", 0, "pwm-backlight", NULL),
> 	};
>
> You can then call:
>
> 	pwm_add_table(hx4700_pwm_lookup, ARRAY_SIZE(hx4700_pwm_lookup));
>
> from hx4700_init(). The pwm-backlight driver will then be able to use
> the new pwm_get() to obtain the PWM device. Note that pwm_request() will
> go away sometime soon, so this conversion will have to be done anyway.
> If you do it now I won't have to take care of it anymore. =)

OK, will do.

BTW, it is possible that the changed numbering scheme will also have
broken three other PXA27X/PXA3XX boards which use PWM1 or PWM2:

cm-x300
tavorevb
z2

Unfortunately I have no way of testing these.

Regards,
Paul