From fc52d0ed11188cae53912a13b44c1a77f058ae26 Mon Sep 17 00:00:00 2001 From: Sean Paul Date: Mon, 13 Aug 2018 17:30:44 -0400 Subject: drm/bridge: ti-sn65dsi86: Poll for DP PLL Lock Instead of just waiting and hoping, actually poll for the pll lock to be acquired. As a bonus, this should be significantly faster than the sleep. Changes in v3: - Added to the set Cc: Sandeep Panda Reviewed-by: Sandeep Panda Signed-off-by: Sean Paul Link: https://patchwork.freedesktop.org/patch/msgid/20180813213058.184821-6-sean@poorly.run --- drivers/gpu/drm/bridge/ti-sn65dsi86.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/ti-sn65dsi86.c b/drivers/gpu/drm/bridge/ti-sn65dsi86.c index d2119ab54614..f02bdedae1e5 100644 --- a/drivers/gpu/drm/bridge/ti-sn65dsi86.c +++ b/drivers/gpu/drm/bridge/ti-sn65dsi86.c @@ -456,6 +456,7 @@ static void ti_sn_bridge_enable(struct drm_bridge *bridge) { struct ti_sn_bridge *pdata = bridge_to_ti_sn_bridge(bridge); unsigned int val; + int ret; /* DSI_A lane config */ val = CHA_DSI_LANES(4 - pdata->dsi->lanes); @@ -472,7 +473,14 @@ static void ti_sn_bridge_enable(struct drm_bridge *bridge) /* enable DP PLL */ regmap_write(pdata->regmap, SN_PLL_ENABLE_REG, 1); - usleep_range(10000, 10500); /* 10ms delay recommended by spec */ + + ret = regmap_read_poll_timeout(pdata->regmap, SN_DPPLL_SRC_REG, val, + val & DPPLL_SRC_DP_PLL_LOCK, 1000, + 50 * 1000); + if (ret) { + DRM_ERROR("DP_PLL_LOCK polling failed (%d)\n", ret); + return; + } /** * The SN65DSI86 only supports ASSR Display Authentication method and -- cgit v1.2.3