For RK3399, the grf clk should be enabled before writing grf registers, otherwise the register value can not be changed.
Signed-off-by: Chris Zhong zyw@rock-chips.com ---
drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 24 ++++++++++++++++++++++++ 1 file changed, 24 insertions(+)
diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c index f84f9ae..d8f24f2 100644 --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c @@ -291,6 +291,7 @@ struct dw_mipi_dsi { struct regmap *grf_regmap; void __iomem *base;
+ struct clk *grf_clk; struct clk *pllref_clk; struct clk *pclk; struct clk *phy_cfg_clk; @@ -979,6 +980,16 @@ static void dw_mipi_dsi_encoder_enable(struct drm_encoder *encoder) dw_mipi_dsi_dphy_interface_config(dsi); dw_mipi_dsi_clear_err(dsi);
+ /* + * For the RK3399, the clk of grf must be enabled before writing grf + * register. + */ + ret = clk_prepare_enable(dsi->grf_clk); + if (ret) { + dev_err(dsi->dev, "Failed to enable grf_clk\n"); + return; + } + if (pdata->grf_dsi0_mode_reg) regmap_write(dsi->grf_regmap, pdata->grf_dsi0_mode_reg, pdata->grf_dsi0_mode); @@ -1003,6 +1014,8 @@ static void dw_mipi_dsi_encoder_enable(struct drm_encoder *encoder) regmap_write(dsi->grf_regmap, pdata->grf_switch_reg, val); dev_dbg(dsi->dev, "vop %s output to dsi0\n", (mux) ? "LIT" : "BIG"); dsi->dpms_mode = DRM_MODE_DPMS_ON; + + clk_disable_unprepare(dsi->grf_clk); }
static int @@ -1238,6 +1251,17 @@ static int dw_mipi_dsi_bind(struct device *dev, struct device *master, dev_dbg(dev, "have not phy_cfg_clk\n"); }
+ dsi->grf_clk = devm_clk_get(dev, "grf"); + if (IS_ERR(dsi->grf_clk)) { + ret = PTR_ERR(dsi->grf_clk); + if (ret != -ENOENT) { + dev_err(dev, "Unable to get grf_clk: %d\n", ret); + return ret; + } + dsi->grf_clk = NULL; + dev_dbg(dev, "have not grf_clk\n"); + } + ret = clk_prepare_enable(dsi->pllref_clk); if (ret) { dev_err(dev, "%s: Failed to enable pllref_clk\n", __func__);