[PATCH v2] drm/bridge/sii8620: simplify hardware reset procedure

[Andrzej Hajda]

On 13.06.2018 15:08, Maciej Purski wrote:
> Hi Andrzej,
>
> On 06/08/2018 08:04 AM, Andrzej Hajda wrote:
>> There is no need to flip reset pin twice. Also delays can be changed to
>> values present in vendor's code.
>>
>> Signed-off-by: Andrzej Hajda <a.hajda at samsung.com>
> Reviewed-by: Maciej Purski <m.purski at samsung.com>

Finally, thanks for the review.
Merged to drm-misc-fixes this and other dependand fixes:

drm/bridge/sii8620: simplify hardware reset procedure
drm/bridge/sii8620: fix loops in EDID fetch logic
drm/bridge/sii8620: fix display modes validation
drm/bridge/sii8620: fix potential buffer overflow
drm/bridge/sii8620: start MHL transmission after HDMI signal detection
drm/bridge/sii8620: remove HSIC initialization
drm/bridge/sii8620: fix HDMI cable connection to dongle

Regards
Andrzej


>
>> ---
>> Hi,
>>
>> This is v2 of forgotten patch, awaiting reviewers, any volunteers.
>> Also "drm/bridge/sii8620: fix loops in EDID fetch logic" waits for reviewers.
>>
>> In this version I have completely removed reset function, and moved its body
>> to sii8620_hw_on.
>>
>> Regards
>> Andrzej
>> ---
>>   drivers/gpu/drm/bridge/sil-sii8620.c | 23 ++++++++++-------------
>>   1 file changed, 10 insertions(+), 13 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/sil-sii8620.c b/drivers/gpu/drm/bridge/sil-sii8620.c
>> index 7ab36042a822..d1e780fba4b6 100644
>> --- a/drivers/gpu/drm/bridge/sil-sii8620.c
>> +++ b/drivers/gpu/drm/bridge/sil-sii8620.c
>> @@ -971,8 +971,17 @@ static int sii8620_hw_on(struct sii8620 *ctx)
>>   	ret = regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
>>   	if (ret)
>>   		return ret;
>> +
>>   	usleep_range(10000, 20000);
>> -	return clk_prepare_enable(ctx->clk_xtal);
>> +	ret = clk_prepare_enable(ctx->clk_xtal);
>> +	if (ret)
>> +		return ret;
>> +
>> +	msleep(100);
>> +	gpiod_set_value(ctx->gpio_reset, 0);
>> +	msleep(100);
>> +
>> +	return 0;
>>   }
>>   
>>   static int sii8620_hw_off(struct sii8620 *ctx)
>> @@ -982,17 +991,6 @@ static int sii8620_hw_off(struct sii8620 *ctx)
>>   	return regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
>>   }
>>   
>> -static void sii8620_hw_reset(struct sii8620 *ctx)
>> -{
>> -	usleep_range(10000, 20000);
>> -	gpiod_set_value(ctx->gpio_reset, 0);
>> -	usleep_range(5000, 20000);
>> -	gpiod_set_value(ctx->gpio_reset, 1);
>> -	usleep_range(10000, 20000);
>> -	gpiod_set_value(ctx->gpio_reset, 0);
>> -	msleep(300);
>> -}
>> -
>>   static void sii8620_cbus_reset(struct sii8620 *ctx)
>>   {
>>   	sii8620_write(ctx, REG_PWD_SRST, BIT_PWD_SRST_CBUS_RST
>> @@ -2112,7 +2110,6 @@ static void sii8620_cable_in(struct sii8620 *ctx)
>>   		dev_err(dev, "Error powering on, %d.\n", ret);
>>   		return;
>>   	}
>> -	sii8620_hw_reset(ctx);
>>   
>>   	sii8620_read_buf(ctx, REG_VND_IDL, ver, ARRAY_SIZE(ver));
>>   	ret = sii8620_clear_error(ctx);
>>
>