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 <philippe.cornu at st.com> > > 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 <a.hajda at samsung.com> 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"); >>> } >>> > >