From: Vladimir Lypak <vladimir.lypak@xxxxxxxxx> There is currently two function for performing reset: dsi_sw_reset and dsi_sw_reset_restore. Only difference betwean those is that latter one assumes that DSI controller is enabled. In contrary former one assumes that controller is disabled and executed during power-on. However this assumtion is not true mobile devices which have boot splash set up by boot-loader. This patch removes dsi_sw_reset_restore and makes dsi_sw_reset disable DSI controller during reset sequence if it's enabled. Signed-off-by: Vladimir Lypak <vladimir.lypak@xxxxxxxxx> Signed-off-by: Luca Weiss <luca@xxxxxxxxx> --- drivers/gpu/drm/msm/dsi/dsi_host.c | 48 +++++++++++++----------------- 1 file changed, 21 insertions(+), 27 deletions(-) diff --git a/drivers/gpu/drm/msm/dsi/dsi_host.c b/drivers/gpu/drm/msm/dsi/dsi_host.c index a95d5df52653..bab2634ebd11 100644 --- a/drivers/gpu/drm/msm/dsi/dsi_host.c +++ b/drivers/gpu/drm/msm/dsi/dsi_host.c @@ -1080,12 +1080,32 @@ static void dsi_timing_setup(struct msm_dsi_host *msm_host, bool is_bonded_dsi) static void dsi_sw_reset(struct msm_dsi_host *msm_host) { + u32 ctrl; + + ctrl = dsi_read(msm_host, REG_DSI_CTRL); + + if (ctrl & DSI_CTRL_ENABLE) { + dsi_write(msm_host, REG_DSI_CTRL, ctrl & ~DSI_CTRL_ENABLE); + /* + * dsi controller need to be disabled before + * clocks turned on + */ + wmb(); + } + dsi_write(msm_host, REG_DSI_CLK_CTRL, DSI_CLK_CTRL_ENABLE_CLKS); wmb(); /* clocks need to be enabled before reset */ + /* dsi controller can only be reset while clocks are running */ dsi_write(msm_host, REG_DSI_RESET, 1); msleep(DSI_RESET_TOGGLE_DELAY_MS); /* make sure reset happen */ dsi_write(msm_host, REG_DSI_RESET, 0); + wmb(); /* controller out of reset */ + + if (ctrl & DSI_CTRL_ENABLE) { + dsi_write(msm_host, REG_DSI_CTRL, ctrl); + wmb(); /* make sure dsi controller enabled again */ + } } static void dsi_op_mode_config(struct msm_dsi_host *msm_host, @@ -1478,32 +1498,6 @@ static int dsi_cmds2buf_tx(struct msm_dsi_host *msm_host, return len; } -static void dsi_sw_reset_restore(struct msm_dsi_host *msm_host) -{ - u32 data0, data1; - - data0 = dsi_read(msm_host, REG_DSI_CTRL); - data1 = data0; - data1 &= ~DSI_CTRL_ENABLE; - dsi_write(msm_host, REG_DSI_CTRL, data1); - /* - * dsi controller need to be disabled before - * clocks turned on - */ - wmb(); - - dsi_write(msm_host, REG_DSI_CLK_CTRL, DSI_CLK_CTRL_ENABLE_CLKS); - wmb(); /* make sure clocks enabled */ - - /* dsi controller can only be reset while clocks are running */ - dsi_write(msm_host, REG_DSI_RESET, 1); - msleep(DSI_RESET_TOGGLE_DELAY_MS); /* make sure reset happen */ - dsi_write(msm_host, REG_DSI_RESET, 0); - wmb(); /* controller out of reset */ - dsi_write(msm_host, REG_DSI_CTRL, data0); - wmb(); /* make sure dsi controller enabled again */ -} - static void dsi_hpd_worker(struct work_struct *work) { struct msm_dsi_host *msm_host = @@ -1520,7 +1514,7 @@ static void dsi_err_worker(struct work_struct *work) pr_err_ratelimited("%s: status=%x\n", __func__, status); if (status & DSI_ERR_STATE_MDP_FIFO_UNDERFLOW) - dsi_sw_reset_restore(msm_host); + dsi_sw_reset(msm_host); /* It is safe to clear here because error irq is disabled. */ msm_host->err_work_state = 0; -- 2.36.1