From: WeiYong Bi <bivvy.bi@rock-chips.com>
Date: Wed, 29 Mar 2017 08:12:34 +0000 (+0800)
Subject: drm/rockchip: dw-mipi: Add reset control for APB
X-Git-Tag: firefly_0821_release~89
X-Git-Url: http://plrg.eecs.uci.edu/git/?p=firefly-linux-kernel-4.4.55.git;a=commitdiff_plain;h=5c7c3607a69cf81753864cce81abc7bdfb64b17a

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

Change-Id: I740b5f6311bfaa6303870ef726be3b1a42b7c4d7
Signed-off-by: WeiYong Bi <bivvy.bi@rock-chips.com>
---

diff --git a/Documentation/devicetree/bindings/display/rockchip/dw_mipi_dsi_rockchip.txt b/Documentation/devicetree/bindings/display/rockchip/dw_mipi_dsi_rockchip.txt
index dc4952e8a0e2..e26bfd4d819e 100644
--- a/Documentation/devicetree/bindings/display/rockchip/dw_mipi_dsi_rockchip.txt
+++ b/Documentation/devicetree/bindings/display/rockchip/dw_mipi_dsi_rockchip.txt
@@ -21,9 +21,12 @@ Optional properties
 - phys: phandle to third party MIPI PHY node
 - phy-names: the string "mipi_dphy" when is found in a node, along with "phys"
   attribute, provides phandle to MIPI PHY node
+- resets : phandle to the reset of MIPI DSI APB Clock.
+- reset-names : should be "apb".
 
 [1] Documentation/devicetree/bindings/clock/clock-bindings.txt
 [2] Documentation/devicetree/bindings/media/video-interfaces.txt
+[3] Documentation/devicetree/bindings/reset/reset.txt
 
 Example:
 
@@ -78,6 +81,8 @@ mipi_dsi_host: mipi-dsi-host@ff960000 {
 	compatible = "rockchip,rk3368-mipi-dsi";
 	phys = <&mipi_dphy>;
 	phy-names = "mipi_dphy";
+	resets = <&cru SRST_MIPIDSI0>;
+	reset-names = "apb";
 	...
 
 	ports@1 {
diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
index 1931247949ff..f938f2be3b71 100644
--- 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);