drm/rockchip: dw-mipi: Add reset control for APB

[firefly-linux-kernel-4.4.55.git] / drivers / gpu / drm / rockchip / dw-mipi-dsi.c

diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
index 1931247949ffdd25482ed7627a2c9e3acb80ec17..f938f2be3b718b3c15259ab6f7bc07b5195177b3 100644 (file)
--- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
+++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
@@ -15,6 +15,7 @@
 #include <linux/phy/phy.h>
 #include <linux/pm_runtime.h>
 #include <linux/regmap.h>
+#include <linux/reset.h>
 #include <linux/mfd/syscon.h>
 #include <drm/drm_atomic_helper.h>
 #include <drm/drm_crtc.h>
@@ -298,6 +299,7 @@ struct dw_mipi_dsi {
        struct drm_panel *panel;
        struct device *dev;
        struct regmap *grf_regmap;
+       struct reset_control *rst;
        void __iomem *base;
 
        struct clk *pllref_clk;
@@ -927,6 +929,14 @@ static void dw_mipi_dsi_encoder_enable(struct drm_encoder *encoder)
                return;
        }
 
+       if (dsi->rst) {
+               /* MIPI DSI APB software reset request. */
+               reset_control_assert(dsi->rst);
+               udelay(10);
+               reset_control_deassert(dsi->rst);
+               udelay(10);
+       }
+
        ret = dw_mipi_dsi_get_lane_bps(dsi);
        if (ret < 0)
                return;
@@ -1250,6 +1260,12 @@ static int dw_mipi_dsi_bind(struct device *dev, struct device *master,
                return ret;
        }
 
+       dsi->rst = devm_reset_control_get_optional(dev, "apb");
+       if (IS_ERR(dsi->rst)) {
+               dev_info(dev, "no reset control specified\n");
+               dsi->rst = NULL;
+       }
+
        ret = dw_mipi_dsi_register(drm, dsi);
        if (ret) {
                dev_err(dev, "Failed to register mipi_dsi: %d\n", ret);