2022-11-22 08:55:28

by Frieder Schrempf

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Subject: [PATCH] drm/bridge: ti-sn65dsi83: Fix delay after reset deassert to match spec

From: Frieder Schrempf <[email protected]>

The datasheet specifies a delay of 10 milliseconds, but the current
driver only waits for 1 ms. Fix this to make sure the initialization
sequence meets the spec.

Fixes: ceb515ba29ba ("drm/bridge: ti-sn65dsi83: Add TI SN65DSI83 and SN65DSI84 driver")
Signed-off-by: Frieder Schrempf <[email protected]>
---
drivers/gpu/drm/bridge/ti-sn65dsi83.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
index 7ba9467fff12..047c14ddbbf1 100644
--- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
+++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
@@ -346,7 +346,7 @@ static void sn65dsi83_atomic_enable(struct drm_bridge *bridge,

/* Deassert reset */
gpiod_set_value_cansleep(ctx->enable_gpio, 1);
- usleep_range(1000, 1100);
+ usleep_range(10000, 11000);

/* Get the LVDS format from the bridge state. */
bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
--
2.38.1


2022-11-24 11:17:09

by Alexander Stein

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Subject: Re: [PATCH] drm/bridge: ti-sn65dsi83: Fix delay after reset deassert to match spec

Am Dienstag, 22. November 2022, 09:12:18 CET schrieb Frieder Schrempf:
> From: Frieder Schrempf <[email protected]>
>
> The datasheet specifies a delay of 10 milliseconds, but the current
> driver only waits for 1 ms. Fix this to make sure the initialization
> sequence meets the spec.
>
> Fixes: ceb515ba29ba ("drm/bridge: ti-sn65dsi83: Add TI SN65DSI83 and
> SN65DSI84 driver") Signed-off-by: Frieder Schrempf
> <[email protected]>
> ---
> drivers/gpu/drm/bridge/ti-sn65dsi83.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
> b/drivers/gpu/drm/bridge/ti-sn65dsi83.c index 7ba9467fff12..047c14ddbbf1
> 100644
> --- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
> @@ -346,7 +346,7 @@ static void sn65dsi83_atomic_enable(struct drm_bridge
> *bridge,
>
> /* Deassert reset */
> gpiod_set_value_cansleep(ctx->enable_gpio, 1);
> - usleep_range(1000, 1100);
> + usleep_range(10000, 11000);
>
> /* Get the LVDS format from the bridge state. */
> bridge_state = drm_atomic_get_new_bridge_state(state, bridge);

How about using fsleep?

Either way:
Reviewed-by: Alexander Stein <[email protected]>


2022-11-24 11:54:12

by Frieder Schrempf

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Subject: Re: [PATCH] drm/bridge: ti-sn65dsi83: Fix delay after reset deassert to match spec

On 24.11.22 12:00, Alexander Stein wrote:
> Am Dienstag, 22. November 2022, 09:12:18 CET schrieb Frieder Schrempf:
>> From: Frieder Schrempf <[email protected]>
>>
>> The datasheet specifies a delay of 10 milliseconds, but the current
>> driver only waits for 1 ms. Fix this to make sure the initialization
>> sequence meets the spec.
>>
>> Fixes: ceb515ba29ba ("drm/bridge: ti-sn65dsi83: Add TI SN65DSI83 and
>> SN65DSI84 driver") Signed-off-by: Frieder Schrempf
>> <[email protected]>
>> ---
>> drivers/gpu/drm/bridge/ti-sn65dsi83.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
>> b/drivers/gpu/drm/bridge/ti-sn65dsi83.c index 7ba9467fff12..047c14ddbbf1
>> 100644
>> --- a/drivers/gpu/drm/bridge/ti-sn65dsi83.c
>> +++ b/drivers/gpu/drm/bridge/ti-sn65dsi83.c
>> @@ -346,7 +346,7 @@ static void sn65dsi83_atomic_enable(struct drm_bridge
>> *bridge,
>>
>> /* Deassert reset */
>> gpiod_set_value_cansleep(ctx->enable_gpio, 1);
>> - usleep_range(1000, 1100);
>> + usleep_range(10000, 11000);
>>
>> /* Get the LVDS format from the bridge state. */
>> bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
>
> How about using fsleep?
>
> Either way:
> Reviewed-by: Alexander Stein <[email protected]>

Thanks for the review! I didn't know about fsleep. Anyway this would
probably be a separate change as the driver currently uses usleep
everywhere else. But I will keep it in mind for the future.

2022-11-24 12:47:04

by Robert Foss

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Subject: Re: [PATCH] drm/bridge: ti-sn65dsi83: Fix delay after reset deassert to match spec

Applied to drm-misc-next.