[RFC PATCH 3/3] drm: bridge: samsung-dsim: Remove init quirk for Exynos

From: Frieder Schrempf
Date: Tue Apr 18 2023 - 06:43:10 EST


From: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>

Assuming that with the init flow fixed to meet the documentation at
[1] and the pre_enable_prev_first flag set in downstream bridge/panel
drivers which require it, we can use the default flow for Exynos as
already done for i.MX8M.

[1] https://docs.kernel.org/gpu/drm-kms-helpers.html#mipi-dsi-bridge-operation

Signed-off-by: Frieder Schrempf <frieder.schrempf@xxxxxxxxxx>
---
I have no idea if my assumptions are correct and if this works at all.
There's a very good chance it doesn't...
---
drivers/gpu/drm/bridge/samsung-dsim.c | 39 ++++++++-------------------
1 file changed, 11 insertions(+), 28 deletions(-)

diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c b/drivers/gpu/drm/bridge/samsung-dsim.c
index 9775779721d9..8c68b767ae50 100644
--- a/drivers/gpu/drm/bridge/samsung-dsim.c
+++ b/drivers/gpu/drm/bridge/samsung-dsim.c
@@ -1336,18 +1336,12 @@ static void samsung_dsim_atomic_pre_enable(struct drm_bridge *bridge,

dsi->state |= DSIM_STATE_ENABLED;

- /*
- * For Exynos-DSIM the downstream bridge, or panel are expecting
- * the host initialization during DSI transfer.
- */
- if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
- ret = samsung_dsim_init(dsi);
- if (ret)
- return;
+ ret = samsung_dsim_init(dsi);
+ if (ret)
+ return;

- samsung_dsim_set_display_mode(dsi);
- samsung_dsim_set_display_enable(dsi, true);
- }
+ samsung_dsim_set_display_mode(dsi);
+ samsung_dsim_set_display_enable(dsi, true);
}

static void samsung_dsim_atomic_enable(struct drm_bridge *bridge,
@@ -1356,14 +1350,9 @@ static void samsung_dsim_atomic_enable(struct drm_bridge *bridge,
struct samsung_dsim *dsi = bridge_to_dsi(bridge);
u32 reg;

- if (samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
- samsung_dsim_set_display_mode(dsi);
- samsung_dsim_set_display_enable(dsi, true);
- } else {
- reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
- reg &= ~DSIM_FORCE_STOP_STATE;
- samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
- }
+ reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
+ reg &= ~DSIM_FORCE_STOP_STATE;
+ samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);

dsi->state |= DSIM_STATE_VIDOUT_AVAILABLE;
}
@@ -1377,11 +1366,9 @@ static void samsung_dsim_atomic_disable(struct drm_bridge *bridge,
if (!(dsi->state & DSIM_STATE_ENABLED))
return;

- if (!samsung_dsim_hw_is_exynos(dsi->plat_data->hw_type)) {
- reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
- reg |= DSIM_FORCE_STOP_STATE;
- samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);
- }
+ reg = samsung_dsim_read(dsi, DSIM_ESCMODE_REG);
+ reg |= DSIM_FORCE_STOP_STATE;
+ samsung_dsim_write(dsi, DSIM_ESCMODE_REG, reg);

dsi->state &= ~DSIM_STATE_VIDOUT_AVAILABLE;
}
@@ -1680,10 +1667,6 @@ static ssize_t samsung_dsim_host_transfer(struct mipi_dsi_host *host,
if (!(dsi->state & DSIM_STATE_ENABLED))
return -EINVAL;

- ret = samsung_dsim_init(dsi);
- if (ret)
- return ret;
-
ret = mipi_dsi_create_packet(&xfer.packet, msg);
if (ret < 0)
return ret;
--
2.40.0