usb: phy: samsung: Add support to set pmu isolation

Adding support to parse device node data in order to get
required properties to set pmu isolation for usb-phy.

Signed-off-by: Vivek Gautam <gautam.vivek@samsung.com>
Acked-by: Kukjin Kim <kgene.kim@samsung.com>
Reviewed-by: Sylwester Nawrocki <s.nawrocki@samsung.com>
Reviewed-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Felipe Balbi <balbi@ti.com>

1 files changed, 141 insertions, 22 deletions

diff --git a/drivers/usb/phy/samsung-usbphy.c b/drivers/usb/phy/samsung-usbphy.c
index 5c5e1bb5de7b..30aebb59d803 100644
--- a/drivers/usb/phy/samsung-usbphy.c
+++ b/drivers/usb/phy/samsung-usbphy.c
@@ -24,6 +24,7 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/of.h>
+#include <linux/of_address.h>
 #include <linux/usb/otg.h>
 #include <linux/platform_data/samsung-usbphy.h>
 
@@ -60,20 +61,46 @@
 #define MHZ (1000*1000)
 #endif
 
+#define S3C64XX_USBPHY_ENABLE                   (0x1 << 16)
+#define EXYNOS_USBPHY_ENABLE                    (0x1 << 0)
+
 enum samsung_cpu_type {
         TYPE_S3C64XX,
         TYPE_EXYNOS4210,
 };
 
 /*
+ * struct samsung_usbphy_drvdata - driver data for various SoC variants
+ * @cpu_type: machine identifier
+ * @devphy_en_mask: device phy enable mask for PHY CONTROL register
+ * @devphy_reg_offset: offset to DEVICE PHY CONTROL register from
+ *                     mapped address of system controller.
+ *
+ *      Here we have a separate mask for device type phy.
+ *      Having different masks for host and device type phy helps
+ *      in setting independent masks in case of SoCs like S5PV210,
+ *      in which PHY0 and PHY1 enable bits belong to same register
+ *      placed at position 0 and 1 respectively.
+ *      Although for newer SoCs like exynos these bits belong to
+ *      different registers altogether placed at position 0.
+ */
+struct samsung_usbphy_drvdata {
+        int cpu_type;
+        int devphy_en_mask;
+        u32 devphy_reg_offset;
+};
+
+/*
  * struct samsung_usbphy - transceiver driver state
  * @phy: transceiver structure
  * @plat: platform data
  * @dev: The parent device supplied to the probe function
  * @clk: usb phy clock
- * @regs: usb phy register memory base
+ * @regs: usb phy controller registers memory base
+ * @pmuregs: USB device PHY_CONTROL register memory base
  * @ref_clk_freq: reference clock frequency selection
- * @cpu_type: machine identifier
+ * @drv_data: driver data available for different SoCs
+ * @lock: lock for phy operations
  */
 struct samsung_usbphy {
         struct usb_phy  phy;
@@ -81,12 +108,66 @@ struct samsung_usbphy {
         struct device   *dev;
         struct clk      *clk;
         void __iomem    *regs;
+        void __iomem    *pmuregs;
         int             ref_clk_freq;
-        int             cpu_type;
+        const struct samsung_usbphy_drvdata *drv_data;
+        spinlock_t      lock;
 };
 
 #define phy_to_sphy(x)          container_of((x), struct samsung_usbphy, phy)
 
+static int samsung_usbphy_parse_dt(struct samsung_usbphy *sphy)
+{
+        struct device_node *usbphy_sys;
+
+        /* Getting node for system controller interface for usb-phy */
+        usbphy_sys = of_get_child_by_name(sphy->dev->of_node, "usbphy-sys");
+        if (!usbphy_sys) {
+                dev_err(sphy->dev, "No sys-controller interface for usb-phy\n");
+                return -ENODEV;
+        }
+
+        sphy->pmuregs = of_iomap(usbphy_sys, 0);
+
+        of_node_put(usbphy_sys);
+
+        if (sphy->pmuregs == NULL) {
+                dev_err(sphy->dev, "Can't get usb-phy pmu control register\n");
+                return -ENODEV;
+        }
+
+        return 0;
+}
+
+/*
+ * Set isolation here for phy.
+ * Here 'on = true' would mean USB PHY block is isolated, hence
+ * de-activated and vice-versa.
+ */
+static void samsung_usbphy_set_isolation(struct samsung_usbphy *sphy, bool on)
+{
+        void __iomem *reg;
+        u32 reg_val;
+        u32 en_mask;
+
+        if (!sphy->pmuregs) {
+                dev_warn(sphy->dev, "Can't set pmu isolation\n");
+                return;
+        }
+
+        reg = sphy->pmuregs + sphy->drv_data->devphy_reg_offset;
+        en_mask = sphy->drv_data->devphy_en_mask;
+
+        reg_val = readl(reg);
+
+        if (on)
+                reg_val &= ~en_mask;
+        else
+                reg_val |= en_mask;
+
+        writel(reg_val, reg);
+}
+
 /*
  * Returns reference clock frequency selection value
  */
@@ -112,7 +193,7 @@ static int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
                 refclk_freq = PHYCLK_CLKSEL_48M;
                 break;
         default:
-                if (sphy->cpu_type == TYPE_S3C64XX)
+                if (sphy->drv_data->cpu_type == TYPE_S3C64XX)
                         refclk_freq = PHYCLK_CLKSEL_48M;
                 else
                         refclk_freq = PHYCLK_CLKSEL_24M;
@@ -135,7 +216,7 @@ static void samsung_usbphy_enable(struct samsung_usbphy *sphy)
         phypwr = readl(regs + SAMSUNG_PHYPWR);
         rstcon = readl(regs + SAMSUNG_RSTCON);
 
-        switch (sphy->cpu_type) {
+        switch (sphy->drv_data->cpu_type) {
         case TYPE_S3C64XX:
                 phyclk &= ~PHYCLK_COMMON_ON_N;
                 phypwr &= ~PHYPWR_NORMAL_MASK;
@@ -165,7 +246,7 @@ static void samsung_usbphy_disable(struct samsung_usbphy *sphy)
 
         phypwr = readl(regs + SAMSUNG_PHYPWR);
 
-        switch (sphy->cpu_type) {
+        switch (sphy->drv_data->cpu_type) {
         case TYPE_S3C64XX:
                 phypwr |= PHYPWR_NORMAL_MASK;
                 break;
@@ -185,6 +266,7 @@ static void samsung_usbphy_disable(struct samsung_usbphy *sphy)
 static int samsung_usbphy_init(struct usb_phy *phy)
 {
         struct samsung_usbphy *sphy;
+        unsigned long flags;
         int ret = 0;
 
         sphy = phy_to_sphy(phy);
@@ -196,13 +278,19 @@ static int samsung_usbphy_init(struct usb_phy *phy)
                 return ret;
         }
 
+        spin_lock_irqsave(&sphy->lock, flags);
+
         /* Disable phy isolation */
         if (sphy->plat && sphy->plat->pmu_isolation)
                 sphy->plat->pmu_isolation(false);
+        else
+                samsung_usbphy_set_isolation(sphy, false);
 
         /* Initialize usb phy registers */
         samsung_usbphy_enable(sphy);
 
+        spin_unlock_irqrestore(&sphy->lock, flags);
+
         /* Disable the phy clock */
         clk_disable_unprepare(sphy->clk);
         return ret;
@@ -214,6 +302,7 @@ static int samsung_usbphy_init(struct usb_phy *phy)
 static void samsung_usbphy_shutdown(struct usb_phy *phy)
 {
         struct samsung_usbphy *sphy;
+        unsigned long flags;
 
         sphy = phy_to_sphy(phy);
 
@@ -222,44 +311,47 @@ static void samsung_usbphy_shutdown(struct usb_phy *phy)
                 return;
         }
 
+        spin_lock_irqsave(&sphy->lock, flags);
+
         /* De-initialize usb phy registers */
         samsung_usbphy_disable(sphy);
 
         /* Enable phy isolation */
         if (sphy->plat && sphy->plat->pmu_isolation)
                 sphy->plat->pmu_isolation(true);
+        else
+                samsung_usbphy_set_isolation(sphy, true);
+
+        spin_unlock_irqrestore(&sphy->lock, flags);
 
         clk_disable_unprepare(sphy->clk);
 }
 
 static const struct of_device_id samsung_usbphy_dt_match[];
 
-static inline int samsung_usbphy_get_driver_data(struct platform_device *pdev)
+static inline const struct samsung_usbphy_drvdata
+*samsung_usbphy_get_driver_data(struct platform_device *pdev)
 {
         if (pdev->dev.of_node) {
                 const struct of_device_id *match;
                 match = of_match_node(samsung_usbphy_dt_match,
                                                         pdev->dev.of_node);
-                return (int) match->data;
+                return match->data;
         }
 
-        return platform_get_device_id(pdev)->driver_data;
+        return (struct samsung_usbphy_drvdata *)
+                                platform_get_device_id(pdev)->driver_data;
 }
 
 static int __devinit samsung_usbphy_probe(struct platform_device *pdev)
 {
         struct samsung_usbphy *sphy;
-        struct samsung_usbphy_data *pdata;
+        struct samsung_usbphy_data *pdata = pdev->dev.platform_data;
         struct device *dev = &pdev->dev;
         struct resource *phy_mem;
         void __iomem    *phy_base;
         struct clk *clk;
-
-        pdata = pdev->dev.platform_data;
-        if (!pdata) {
-                dev_err(&pdev->dev, "%s: no platform data defined\n", __func__);
-                return -EINVAL;
-        }
+        int ret;
 
         phy_mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
         if (!phy_mem) {
@@ -283,7 +375,19 @@ static int __devinit samsung_usbphy_probe(struct platform_device *pdev)
                 return PTR_ERR(clk);
         }
 
-        sphy->dev               = &pdev->dev;
+        sphy->dev = dev;
+
+        if (dev->of_node) {
+                ret = samsung_usbphy_parse_dt(sphy);
+                if (ret < 0)
+                        return ret;
+        } else {
+                if (!pdata) {
+                        dev_err(dev, "no platform data specified\n");
+                        return -EINVAL;
+                }
+        }
+
         sphy->plat              = pdata;
         sphy->regs              = phy_base;
         sphy->clk               = clk;
@@ -291,9 +395,11 @@ static int __devinit samsung_usbphy_probe(struct platform_device *pdev)
         sphy->phy.label         = "samsung-usbphy";
         sphy->phy.init          = samsung_usbphy_init;
         sphy->phy.shutdown      = samsung_usbphy_shutdown;
-        sphy->cpu_type          = samsung_usbphy_get_driver_data(pdev);
+        sphy->drv_data          = samsung_usbphy_get_driver_data(pdev);
         sphy->ref_clk_freq      = samsung_usbphy_get_refclk_freq(sphy);
 
+        spin_lock_init(&sphy->lock);
+
         platform_set_drvdata(pdev, sphy);
 
         return usb_add_phy(&sphy->phy, USB_PHY_TYPE_USB2);
@@ -305,17 +411,30 @@ static int __exit samsung_usbphy_remove(struct platform_device *pdev)
 
         usb_remove_phy(&sphy->phy);
 
+        if (sphy->pmuregs)
+                iounmap(sphy->pmuregs);
+
         return 0;
 }
 
+static const struct samsung_usbphy_drvdata usbphy_s3c64xx = {
+        .cpu_type               = TYPE_S3C64XX,
+        .devphy_en_mask         = S3C64XX_USBPHY_ENABLE,
+};
+
+static const struct samsung_usbphy_drvdata usbphy_exynos4 = {
+        .cpu_type               = TYPE_EXYNOS4210,
+        .devphy_en_mask         = EXYNOS_USBPHY_ENABLE,
+};
+
 #ifdef CONFIG_OF
 static const struct of_device_id samsung_usbphy_dt_match[] = {
         {
                 .compatible = "samsung,s3c64xx-usbphy",
-                .data = (void *)TYPE_S3C64XX,
+                .data = &usbphy_s3c64xx,
         }, {
                 .compatible = "samsung,exynos4210-usbphy",
-                .data = (void *)TYPE_EXYNOS4210,
+                .data = &usbphy_exynos4,
         },
         {},
 };
@@ -325,10 +444,10 @@ MODULE_DEVICE_TABLE(of, samsung_usbphy_dt_match);
 static struct platform_device_id samsung_usbphy_driver_ids[] = {
         {
                 .name           = "s3c64xx-usbphy",
-                .driver_data    = TYPE_S3C64XX,
+                .driver_data    = (unsigned long)&usbphy_s3c64xx,
         }, {
                 .name           = "exynos4210-usbphy",
-                .driver_data    = TYPE_EXYNOS4210,
+                .driver_data    = (unsigned long)&usbphy_exynos4,
         },
         {},
 };