[PATCH 4.19 075/191] drm/bridge/synopsys: dsi: add support for non-continuous HS clock

From: Greg Kroah-Hartman
Date: Tue Nov 03 2020 - 16:04:05 EST


From: Antonio Borneo <antonio.borneo@xxxxxx>

[ Upstream commit c6d94e37bdbb6dfe7e581e937a915ab58399b8a5 ]

Current code enables the HS clock when video mode is started or to
send out a HS command, and disables the HS clock to send out a LP
command. This is not what DSI spec specify.

Enable HS clock either in command and in video mode.
Set automatic HS clock management for panels and devices that
support non-continuous HS clock.

Signed-off-by: Antonio Borneo <antonio.borneo@xxxxxx>
Tested-by: Philippe Cornu <philippe.cornu@xxxxxx>
Reviewed-by: Philippe Cornu <philippe.cornu@xxxxxx>
Acked-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Signed-off-by: Neil Armstrong <narmstrong@xxxxxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20200701194234.18123-1-yannick.fertre@xxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
index fd7999642cf8a..8b5f9241a8876 100644
--- a/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/bridge/synopsys/dw-mipi-dsi.c
@@ -326,7 +326,6 @@ static void dw_mipi_message_config(struct dw_mipi_dsi *dsi,
if (lpm)
val |= CMD_MODE_ALL_LP;

- dsi_write(dsi, DSI_LPCLK_CTRL, lpm ? 0 : PHY_TXREQUESTCLKHS);
dsi_write(dsi, DSI_CMD_MODE_CFG, val);
}

@@ -488,16 +487,22 @@ static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
static void dw_mipi_dsi_set_mode(struct dw_mipi_dsi *dsi,
unsigned long mode_flags)
{
+ u32 val;
+
dsi_write(dsi, DSI_PWR_UP, RESET);

if (mode_flags & MIPI_DSI_MODE_VIDEO) {
dsi_write(dsi, DSI_MODE_CFG, ENABLE_VIDEO_MODE);
dw_mipi_dsi_video_mode_config(dsi);
- dsi_write(dsi, DSI_LPCLK_CTRL, PHY_TXREQUESTCLKHS);
} else {
dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
}

+ val = PHY_TXREQUESTCLKHS;
+ if (dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
+ val |= AUTO_CLKLANE_CTRL;
+ dsi_write(dsi, DSI_LPCLK_CTRL, val);
+
dsi_write(dsi, DSI_PWR_UP, POWERUP);
}

--
2.27.0