lkml.org 
[lkml]   [2016]   [Nov]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [RFC][PATCH 1/3] drm/bridge: adv7511: Rework adv7511_power_on/off() so they can be reused internally
On Tue, Nov 22, 2016 at 12:14 AM, Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
> Hi John,
>
> Thank you for the patch.
>
> On Monday 21 Nov 2016 16:37:30 John Stultz wrote:
>> In chasing down issues with EDID probing, I found some
>> duplicated but incomplete logic used to power the chip on and
>> off.
>>
>> This patch refactors the adv7511_power_on/off functions, so
>> they can be used for internal needs, and replaces duplicative
>> logic that powers the chip on and off around the EDID probing
>> with the common logic.
>>
>> Cc: David Airlie <airlied@linux.ie>
>> Cc: Archit Taneja <architt@codeaurora.org>
>> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com>
>> Cc: Lars-Peter Clausen <lars@metafoo.de>
>> Cc: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
>> Cc: dri-devel@lists.freedesktop.org
>> Signed-off-by: John Stultz <john.stultz@linaro.org>
>> ---
>> drivers/gpu/drm/bridge/adv7511/adv7511_drv.c | 30 +++++++++++--------------
>> 1 file changed, 14 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
>> b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c index 8dba729..b240e05
>> 100644
>> --- a/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
>> +++ b/drivers/gpu/drm/bridge/adv7511/adv7511_drv.c
>> @@ -325,7 +325,7 @@ static void adv7511_set_link_config(struct adv7511
>> *adv7511, adv7511->rgb = config->input_colorspace == HDMI_COLORSPACE_RGB;
>> }
>>
>> -static void adv7511_power_on(struct adv7511 *adv7511)
>> +static void __adv7511_power_on(struct adv7511 *adv7511)
>> {
>> adv7511->current_edid_segment = -1;
>>
>> @@ -343,6 +343,7 @@ static void adv7511_power_on(struct adv7511 *adv7511)
>> ADV7511_INT1_DDC_ERROR);
>> }
>>
>> +
>
> This isn't needed.

Apologies. I saw this right after I sent it!

>> /*
>> * Per spec it is allowed to pulse the HPD signal to indicate that the
>> * EDID information has changed. Some monitors do this when they
> wakeup
>> @@ -362,11 +363,15 @@ static void adv7511_power_on(struct adv7511 *adv7511)
>>
>> if (adv7511->type == ADV7533)
>> adv7533_dsi_power_on(adv7511);
>> +}
>>
>> +static void adv7511_power_on(struct adv7511 *adv7511)
>> +{
>> + __adv7511_power_on(adv7511);
>> adv7511->powered = true;
>> }
>>
>> -static void adv7511_power_off(struct adv7511 *adv7511)
>> +static void __adv7511_power_off(struct adv7511 *adv7511)
>> {
>> /* TODO: setup additional power down modes */
>> regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
>> @@ -376,7 +381,11 @@ static void adv7511_power_off(struct adv7511 *adv7511)
>>
>> if (adv7511->type == ADV7533)
>> adv7533_dsi_power_off(adv7511);
>> +}
>>
>> +static void adv7511_power_off(struct adv7511 *adv7511)
>> +{
>> + __adv7511_power_off(adv7511);
>> adv7511->powered = false;
>> }
>>
>> @@ -545,24 +554,13 @@ static int adv7511_get_modes(struct adv7511 *adv7511,
>> unsigned int count;
>>
>> /* Reading the EDID only works if the device is powered */
>> - if (!adv7511->powered) {
>> - regmap_update_bits(adv7511->regmap, ADV7511_REG_POWER,
>> - ADV7511_POWER_POWER_DOWN, 0);
>> - if (adv7511->i2c_main->irq) {
>> - regmap_write(adv7511->regmap,
> ADV7511_REG_INT_ENABLE(0),
>> - ADV7511_INT0_EDID_READY);
>> - regmap_write(adv7511->regmap,
> ADV7511_REG_INT_ENABLE(1),
>> - ADV7511_INT1_DDC_ERROR);
>> - }
>> - adv7511->current_edid_segment = -1;
>> - }
>> + if (!adv7511->powered)
>> + __adv7511_power_on(adv7511);
>
> The __adv7511_power_on() function does more than the above, in particular it
> performs an expensive regcache_sync() and calls adv7533_dsi_power_on() for the
> ADV7533. Don't those operations have side effects that are either not wanted
> or not needed here ? In any case this patch modifies the behaviour of the
> driver, which needs to be documented in the kernel message.

Sorry, what do you mean by kernel message? Commit message, maybe?

Fair point, I'll review the adv7533_dsi_power_on bits and see if they
should move out to the external function rather then the internal one.
Similarly for the regcache_sync.

Thanks so much for the review!

thanks
-john

\
 
 \ /
  Last update: 2016-11-22 09:17    [W:0.256 / U:0.060 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site