2018-02-04 21:38:07

by Philippe Cornu

[permalink] [raw]
Subject: [PATCH] drm/bridge/synopsys: dsi: readl_poll_timeout return value clean up

The readl_poll_timeout() return value is 0 in case of success
so it is better to detect errors without taking care of the
return value sign.

Signed-off-by: Philippe Cornu <[email protected]>
---
drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index 65aeb3f78b48..4d0e8471a15c 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -342,7 +342,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
val, !(val & GEN_CMD_FULL), 1000,
CMD_PKT_STATUS_TIMEOUT_US);
- if (ret < 0) {
+ if (ret) {
dev_err(dsi->dev, "failed to get available command FIFO\n");
return ret;
}
@@ -353,7 +353,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
val, (val & mask) == mask,
1000, CMD_PKT_STATUS_TIMEOUT_US);
- if (ret < 0) {
+ if (ret) {
dev_err(dsi->dev, "failed to write command FIFO\n");
return ret;
}
@@ -385,7 +385,7 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
val, !(val & GEN_PLD_W_FULL), 1000,
CMD_PKT_STATUS_TIMEOUT_US);
- if (ret < 0) {
+ if (ret) {
dev_err(dsi->dev,
"failed to get available write payload FIFO\n");
return ret;
@@ -716,13 +716,13 @@ static void dw_mipi_dsi_dphy_enable(struct dw_mipi_dsi *dsi)

ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS, val,
val & PHY_LOCK, 1000, PHY_STATUS_TIMEOUT_US);
- if (ret < 0)
+ if (ret)
DRM_DEBUG_DRIVER("failed to wait phy lock state\n");

ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS,
val, val & PHY_STOP_STATE_CLK_LANE, 1000,
PHY_STATUS_TIMEOUT_US);
- if (ret < 0)
+ if (ret)
DRM_DEBUG_DRIVER("failed to wait phy clk lane stop state\n");
}

--
2.15.1



2018-03-01 09:02:38

by Philippe Cornu

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge/synopsys: dsi: readl_poll_timeout return value clean up

Hi Archit, Andrzej & Laurent,

May I ask you please your feedback on this small patch?
Many thanks,

Philippe :-)

On 02/04/2018 10:36 PM, Philippe Cornu wrote:
> The readl_poll_timeout() return value is 0 in case of success
> so it is better to detect errors without taking care of the
> return value sign.
>
> Signed-off-by: Philippe Cornu <[email protected]>
> ---
> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 10 +++++-----
> 1 file changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> index 65aeb3f78b48..4d0e8471a15c 100644
> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
> @@ -342,7 +342,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> val, !(val & GEN_CMD_FULL), 1000,
> CMD_PKT_STATUS_TIMEOUT_US);
> - if (ret < 0) {
> + if (ret) {
> dev_err(dsi->dev, "failed to get available command FIFO\n");
> return ret;
> }
> @@ -353,7 +353,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> val, (val & mask) == mask,
> 1000, CMD_PKT_STATUS_TIMEOUT_US);
> - if (ret < 0) {
> + if (ret) {
> dev_err(dsi->dev, "failed to write command FIFO\n");
> return ret;
> }
> @@ -385,7 +385,7 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
> val, !(val & GEN_PLD_W_FULL), 1000,
> CMD_PKT_STATUS_TIMEOUT_US);
> - if (ret < 0) {
> + if (ret) {
> dev_err(dsi->dev,
> "failed to get available write payload FIFO\n");
> return ret;
> @@ -716,13 +716,13 @@ static void dw_mipi_dsi_dphy_enable(struct dw_mipi_dsi *dsi)
>
> ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS, val,
> val & PHY_LOCK, 1000, PHY_STATUS_TIMEOUT_US);
> - if (ret < 0)
> + if (ret)
> DRM_DEBUG_DRIVER("failed to wait phy lock state\n");
>
> ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS,
> val, val & PHY_STOP_STATE_CLK_LANE, 1000,
> PHY_STATUS_TIMEOUT_US);
> - if (ret < 0)
> + if (ret)
> DRM_DEBUG_DRIVER("failed to wait phy clk lane stop state\n");
> }
>
>

2018-03-02 10:40:21

by Andrzej Hajda

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge/synopsys: dsi: readl_poll_timeout return value clean up

On 01.03.2018 10:00, Philippe CORNU wrote:
> Hi Archit, Andrzej & Laurent,
>
> May I ask you please your feedback on this small patch?
> Many thanks,
>
> Philippe :-)
>
> On 02/04/2018 10:36 PM, Philippe Cornu wrote:
>> The readl_poll_timeout() return value is 0 in case of success
>> so it is better to detect errors without taking care of the
>> return value sign.
>>
>> Signed-off-by: Philippe Cornu <[email protected]>

The patch is of course correct. However I am not sure if necessary. For
sure functionally it does not change anything.
AFAIK kernel CodingStyle says nothing about it, so I suppose it is
matter of personal taste.
Anyway I can give it:
Reviewed-by: Andrzej Hajda <[email protected]>

 --
Regards
Andrzej

>> ---
>> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 10 +++++-----
>> 1 file changed, 5 insertions(+), 5 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> index 65aeb3f78b48..4d0e8471a15c 100644
>> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>> @@ -342,7 +342,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>> ret = qq(dsi->base + DSI_CMD_PKT_STATUS,
>> val, !(val & GEN_CMD_FULL), 1000,
>> CMD_PKT_STATUS_TIMEOUT_US);
>> - if (ret < 0) {
>> + if (ret) {
>> dev_err(dsi->dev, "failed to get available command FIFO\n");
>> return ret;
>> }
>> @@ -353,7 +353,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
>> val, (val & mask) == mask,
>> 1000, CMD_PKT_STATUS_TIMEOUT_US);
>> - if (ret < 0) {
>> + if (ret) {
>> dev_err(dsi->dev, "failed to write command FIFO\n");
>> return ret;
>> }
>> @@ -385,7 +385,7 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
>> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
>> val, !(val & GEN_PLD_W_FULL), 1000,
>> CMD_PKT_STATUS_TIMEOUT_US);
>> - if (ret < 0) {
>> + if (ret) {
>> dev_err(dsi->dev,
>> "failed to get available write payload FIFO\n");
>> return ret;
>> @@ -716,13 +716,13 @@ static void dw_mipi_dsi_dphy_enable(struct dw_mipi_dsi *dsi)
>>
>> ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS, val,
>> val & PHY_LOCK, 1000, PHY_STATUS_TIMEOUT_US);
>> - if (ret < 0)
>> + if (ret)
>> DRM_DEBUG_DRIVER("failed to wait phy lock state\n");
>>
>> ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS,
>> val, val & PHY_STOP_STATE_CLK_LANE, 1000,
>> PHY_STATUS_TIMEOUT_US);
>> - if (ret < 0)
>> + if (ret)
>> DRM_DEBUG_DRIVER("failed to wait phy clk lane stop state\n");
>> }
>>



2018-03-02 15:33:05

by Philippe Cornu

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge/synopsys: dsi: readl_poll_timeout return value clean up

Hi Andrzej,


On 03/02/2018 11:21 AM, Andrzej Hajda wrote:
> On 01.03.2018 10:00, Philippe CORNU wrote:
>> Hi Archit, Andrzej & Laurent,
>>
>> May I ask you please your feedback on this small patch?
>> Many thanks,
>>
>> Philippe :-)
>>
>> On 02/04/2018 10:36 PM, Philippe Cornu wrote:
>>> The readl_poll_timeout() return value is 0 in case of success
>>> so it is better to detect errors without taking care of the
>>> return value sign.
>>>
>>> Signed-off-by: Philippe Cornu <[email protected]>
>
> The patch is of course correct. However I am not sure if necessary. For
> sure functionally it does not change anything.
> AFAIK kernel CodingStyle says nothing about it, so I suppose it is
> matter of personal taste.

I sent this tiny patch in order to homogenize the dw mipi driver because
there were both cases "if (ret)" & "if (ret < 0)" in the source code.

I did not really find a preferred way in the kernel source code so I
selected what sounds the best to me ie "if (ret)" but it is not a
problem to make another patch for "if (ret < 0)" everywhere :-)

In any case, the most important from my pov is to have a homogeneous
source code :-)

Does anyone have a preferred choice between "if (ret)" & "if (ret < 0)"
after a "ret = readl_poll_timeout()"?

> Anyway I can give it:
> Reviewed-by: Andrzej Hajda <[email protected]>

Many thanks,
Philippe :)

>
>  --
> Regards
> Andrzej
>
>>> ---
>>> drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 10 +++++-----
>>> 1 file changed, 5 insertions(+), 5 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>> index 65aeb3f78b48..4d0e8471a15c 100644
>>> --- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>> +++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
>>> @@ -342,7 +342,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>>> ret = qq(dsi->base + DSI_CMD_PKT_STATUS,
>>> val, !(val & GEN_CMD_FULL), 1000,
>>> CMD_PKT_STATUS_TIMEOUT_US);
>>> - if (ret < 0) {
>>> + if (ret) {
>>> dev_err(dsi->dev, "failed to get available command FIFO\n");
>>> return ret;
>>> }
>>> @@ -353,7 +353,7 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>>> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
>>> val, (val & mask) == mask,
>>> 1000, CMD_PKT_STATUS_TIMEOUT_US);
>>> - if (ret < 0) {
>>> + if (ret) {
>>> dev_err(dsi->dev, "failed to write command FIFO\n");
>>> return ret;
>>> }
>>> @@ -385,7 +385,7 @@ static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
>>> ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
>>> val, !(val & GEN_PLD_W_FULL), 1000,
>>> CMD_PKT_STATUS_TIMEOUT_US);
>>> - if (ret < 0) {
>>> + if (ret) {
>>> dev_err(dsi->dev,
>>> "failed to get available write payload FIFO\n");
>>> return ret;
>>> @@ -716,13 +716,13 @@ static void dw_mipi_dsi_dphy_enable(struct dw_mipi_dsi *dsi)
>>>
>>> ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS, val,
>>> val & PHY_LOCK, 1000, PHY_STATUS_TIMEOUT_US);
>>> - if (ret < 0)
>>> + if (ret)
>>> DRM_DEBUG_DRIVER("failed to wait phy lock state\n");
>>>
>>> ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS,
>>> val, val & PHY_STOP_STATE_CLK_LANE, 1000,
>>> PHY_STATUS_TIMEOUT_US);
>>> - if (ret < 0)
>>> + if (ret)
>>> DRM_DEBUG_DRIVER("failed to wait phy clk lane stop state\n");
>>> }
>>>
>
>

2018-03-05 14:19:26

by Andrzej Hajda

[permalink] [raw]
Subject: Re: [PATCH] drm/bridge/synopsys: dsi: readl_poll_timeout return value clean up

On 02.03.2018 14:15, Philippe CORNU wrote:
> Hi Andrzej,
>
>
> On 03/02/2018 11:21 AM, Andrzej Hajda wrote:
>> On 01.03.2018 10:00, Philippe CORNU wrote:
>>> Hi Archit, Andrzej & Laurent,
>>>
>>> May I ask you please your feedback on this small patch?
>>> Many thanks,
>>>
>>> Philippe :-)
>>>
>>> On 02/04/2018 10:36 PM, Philippe Cornu wrote:
>>>> The readl_poll_timeout() return value is 0 in case of success
>>>> so it is better to detect errors without taking care of the
>>>> return value sign.
>>>>
>>>> Signed-off-by: Philippe Cornu <[email protected]>
>> The patch is of course correct. However I am not sure if necessary. For
>> sure functionally it does not change anything.
>> AFAIK kernel CodingStyle says nothing about it, so I suppose it is
>> matter of personal taste.
> I sent this tiny patch in order to homogenize the dw mipi driver because
> there were both cases "if (ret)" & "if (ret < 0)" in the source code.
>
> I did not really find a preferred way in the kernel source code so I
> selected what sounds the best to me ie "if (ret)" but it is not a
> problem to make another patch for "if (ret < 0)" everywhere :-)
>
> In any case, the most important from my pov is to have a homogeneous
> source code :-)

OK

Queued to drm-misc-next.

Regards
Andrzej