[PATCH v3 1/3] phy: exynos-dp-video: Use syscon support to control pmu register

[Vivek Gautam]

Currently the DP_PHY_ENABLE register is mapped in the driver,
and accessed to control power to the PHY.
With mfd-syscon and regmap interface available at our disposal,
it's wise to use that instead of using a 'reg' property for the
controller and allocating a memory resource for that.

To facilitate this, we have added another compatible string
for Exynso5420 SoC to acquire driver data which contains
different DP-PHY-CONTROL register offset.

Signed-off-by: Vivek Gautam <gautam.vivek at samsung.com>
Cc: Jingoo Han <jg1.han at samsung.com>
Cc: Kishon Vijay Abraham I <kishon at ti.com>
---

Changes since v2:
 - Using 'EXYNOS5_PHY_ENABLE' macro instead of 'EXYNOS_DPTX_PHY_ENABLE'
   since that's available with us in "linux/mfd/syscon/exynos5-pmu.h" file.

Changes since v1:
 - state->regs should have been "struct regmap *" instead of
   "void __iomem *". So corrected the same.

 .../devicetree/bindings/phy/samsung-phy.txt        |    7 +-
 drivers/phy/phy-exynos-dp-video.c                  |   79 +++++++++++++-------
 2 files changed, 59 insertions(+), 27 deletions(-)

diff --git a/Documentation/devicetree/bindings/phy/samsung-phy.txt b/Documentation/devicetree/bindings/phy/samsung-phy.txt
index 7a6feea..15e0f2c 100644
--- a/Documentation/devicetree/bindings/phy/samsung-phy.txt
+++ b/Documentation/devicetree/bindings/phy/samsung-phy.txt
@@ -17,8 +17,11 @@ Samsung EXYNOS SoC series Display Port PHY
 -------------------------------------------------
 
 Required properties:
-- compatible : should be "samsung,exynos5250-dp-video-phy";
-- reg : offset and length of the Display Port PHY register set;
+- compatible : should be one of the following supported values:
+	 - "samsung,exynos5250-dp-video-phy"
+	 - "samsung,exynos5420-dp-video-phy"
+- samsung,pmu-syscon: phandle for PMU system controller interface, used to
+		      control pmu registers for power isolation.
 - #phy-cells : from the generic PHY bindings, must be 0;
 
 Samsung S5P/EXYNOS SoC series USB PHY
diff --git a/drivers/phy/phy-exynos-dp-video.c b/drivers/phy/phy-exynos-dp-video.c
index 8b3026e..53f44a0 100644
--- a/drivers/phy/phy-exynos-dp-video.c
+++ b/drivers/phy/phy-exynos-dp-video.c
@@ -13,44 +13,55 @@
 #include <linux/io.h>
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/exynos5-pmu.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
 #include <linux/phy/phy.h>
 #include <linux/platform_device.h>
+#include <linux/regmap.h>
 
-/* DPTX_PHY_CONTROL register */
-#define EXYNOS_DPTX_PHY_ENABLE		(1 << 0)
+struct exynos_dp_video_phy_drvdata {
+	u32 phy_ctrl_offset;
+};
 
 struct exynos_dp_video_phy {
-	void __iomem *regs;
+	struct regmap *regs;
+	const struct exynos_dp_video_phy_drvdata *drvdata;
 };
 
-static int __set_phy_state(struct exynos_dp_video_phy *state, unsigned int on)
+static void exynos_dp_video_phy_pwr_isol(struct exynos_dp_video_phy *state,
+							unsigned int on)
 {
-	u32 reg;
+	unsigned int val;
+
+	if (IS_ERR(state->regs))
+		return;
 
-	reg = readl(state->regs);
-	if (on)
-		reg |= EXYNOS_DPTX_PHY_ENABLE;
-	else
-		reg &= ~EXYNOS_DPTX_PHY_ENABLE;
-	writel(reg, state->regs);
+	val = on ? 0 : EXYNOS5_PHY_ENABLE;
 
-	return 0;
+	regmap_update_bits(state->regs, state->drvdata->phy_ctrl_offset,
+			   EXYNOS5_PHY_ENABLE, val);
 }
 
 static int exynos_dp_video_phy_power_on(struct phy *phy)
 {
 	struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
 
-	return __set_phy_state(state, 1);
+	/* Disable power isolation on DP-PHY */
+	exynos_dp_video_phy_pwr_isol(state, 0);
+
+	return 0;
 }
 
 static int exynos_dp_video_phy_power_off(struct phy *phy)
 {
 	struct exynos_dp_video_phy *state = phy_get_drvdata(phy);
 
-	return __set_phy_state(state, 0);
+	/* Enable power isolation on DP-PHY */
+	exynos_dp_video_phy_pwr_isol(state, 1);
+
+	return 0;
 }
 
 static struct phy_ops exynos_dp_video_phy_ops = {
@@ -59,11 +70,31 @@ static struct phy_ops exynos_dp_video_phy_ops = {
 	.owner		= THIS_MODULE,
 };
 
+static const struct exynos_dp_video_phy_drvdata exynos5250_dp_video_phy = {
+	.phy_ctrl_offset	= EXYNOS5_DPTX_PHY_CONTROL,
+};
+
+static const struct exynos_dp_video_phy_drvdata exynos5420_dp_video_phy = {
+	.phy_ctrl_offset	= EXYNOS5420_DPTX_PHY_CONTROL,
+};
+
+static const struct of_device_id exynos_dp_video_phy_of_match[] = {
+	{
+		.compatible = "samsung,exynos5250-dp-video-phy",
+		.data = &exynos5250_dp_video_phy,
+	}, {
+		.compatible = "samsung,exynos5420-dp-video-phy",
+		.data = &exynos5420_dp_video_phy,
+	},
+	{ },
+};
+MODULE_DEVICE_TABLE(of, exynos_dp_video_phy_of_match);
+
 static int exynos_dp_video_phy_probe(struct platform_device *pdev)
 {
 	struct exynos_dp_video_phy *state;
 	struct device *dev = &pdev->dev;
-	struct resource *res;
+	const struct of_device_id *match;
 	struct phy_provider *phy_provider;
 	struct phy *phy;
 
@@ -71,11 +102,15 @@ static int exynos_dp_video_phy_probe(struct platform_device *pdev)
 	if (!state)
 		return -ENOMEM;
 
-	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
-
-	state->regs = devm_ioremap_resource(dev, res);
-	if (IS_ERR(state->regs))
+	state->regs = syscon_regmap_lookup_by_phandle(dev->of_node,
+						      "samsung,pmu-syscon");
+	if (IS_ERR(state->regs)) {
+		dev_err(dev, "Failed to lookup PMU regmap\n");
 		return PTR_ERR(state->regs);
+	}
+
+	match = of_match_node(exynos_dp_video_phy_of_match, dev->of_node);
+	state->drvdata = match->data;
 
 	phy = devm_phy_create(dev, NULL, &exynos_dp_video_phy_ops, NULL);
 	if (IS_ERR(phy)) {
@@ -89,12 +124,6 @@ static int exynos_dp_video_phy_probe(struct platform_device *pdev)
 	return PTR_ERR_OR_ZERO(phy_provider);
 }
 
-static const struct of_device_id exynos_dp_video_phy_of_match[] = {
-	{ .compatible = "samsung,exynos5250-dp-video-phy" },
-	{ },
-};
-MODULE_DEVICE_TABLE(of, exynos_dp_video_phy_of_match);
-
 static struct platform_driver exynos_dp_video_phy_driver = {
 	.probe	= exynos_dp_video_phy_probe,
 	.driver = {
-- 
1.7.10.4