On 20.07.2022 17:52, Jagan Teki wrote: > Host transfer() in DSI master will invoke only when the DSI commands > are sent from DSI devices like DSI Panel or DSI bridges and this > host transfer wouldn't invoke for I2C-based-DSI bridge drivers. > > Handling DSI host initialization in transfer calls misses the > controller setup for I2C configured DSI bridges. > > This patch adds the DSI initialization from transfer to bridge > pre_enable as the bridge pre_enable API is invoked by core as > it is common across all classes of DSI device drivers.
This is still problematic in case of Exynos. Without a workaround like this https://github.com/mszyprow/linux/commit/11bbfc61272da9610dd5c574bb8ef838dc150961 the display on the all real DSI panels on my Exynos based boards is broken. > > v3: > * none > > v2: > * check initialized state in samsung_dsim_init > > v1: > * keep DSI init in host transfer > > Signed-off-by: Jagan Teki <ja...@amarulasolutions.com> > --- > drivers/gpu/drm/bridge/samsung-dsim.c | 18 ++++++++++++------ > 1 file changed, 12 insertions(+), 6 deletions(-) > > diff --git a/drivers/gpu/drm/bridge/samsung-dsim.c > b/drivers/gpu/drm/bridge/samsung-dsim.c > index 9b74a3f98a17..b07909a52f2d 100644 > --- a/drivers/gpu/drm/bridge/samsung-dsim.c > +++ b/drivers/gpu/drm/bridge/samsung-dsim.c > @@ -1258,6 +1258,9 @@ static int samsung_dsim_init(struct samsung_dsim *dsi) > { > const struct samsung_dsim_driver_data *driver_data = dsi->driver_data; > > + if (dsi->state & DSIM_STATE_INITIALIZED) > + return 0; > + > samsung_dsim_reset(dsi); > samsung_dsim_enable_irq(dsi); > > @@ -1270,6 +1273,8 @@ static int samsung_dsim_init(struct samsung_dsim *dsi) > samsung_dsim_set_phy_ctrl(dsi); > samsung_dsim_init_link(dsi); > > + dsi->state |= DSIM_STATE_INITIALIZED; > + > return 0; > } > > @@ -1289,6 +1294,10 @@ static void samsung_dsim_atomic_pre_enable(struct > drm_bridge *bridge, > } > > dsi->state |= DSIM_STATE_ENABLED; > + > + ret = samsung_dsim_init(dsi); > + if (ret) > + return; > } > > static void samsung_dsim_atomic_enable(struct drm_bridge *bridge, > @@ -1464,12 +1473,9 @@ static ssize_t samsung_dsim_host_transfer(struct > mipi_dsi_host *host, > if (!(dsi->state & DSIM_STATE_ENABLED)) > return -EINVAL; > > - if (!(dsi->state & DSIM_STATE_INITIALIZED)) { > - ret = samsung_dsim_init(dsi); > - if (ret) > - return ret; > - dsi->state |= DSIM_STATE_INITIALIZED; > - } > + ret = samsung_dsim_init(dsi); > + if (ret) > + return ret; > > ret = mipi_dsi_create_packet(&xfer.packet, msg); > if (ret < 0) Best regards -- Marek Szyprowski, PhD Samsung R&D Institute Poland
