phy: ti-pipe3: fix suspend
authorRoger Quadros <rogerq@ti.com>
Tue, 2 Jun 2015 09:10:40 +0000 (12:10 +0300)
committerKishon Vijay Abraham I <kishon@ti.com>
Wed, 15 Jul 2015 14:32:09 +0000 (20:02 +0530)
Relying on PM-ops for shutting down PHY clocks was a
bad idea since the users (e.g. PCIe/SATA) might not
have been suspended by then.

The main culprit for not shutting down the clocks was
the stray pm_runtime_get() call in probe.

Fix the whole thing in the right way by getting rid
of that pm_runtime_get() call from probe and
removing all PM-ops. It is the sole responsibility
of the PHY user to properly turn OFF and de-initialize
the PHY as part of its suspend routine.

As PHY core serializes init/exit we don't need
to use a spinlock in this driver. So get rid of it.

Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
drivers/phy/phy-ti-pipe3.c

index 53f295c1bab1a72108d84b955714b8aef4d7e951..3510b81db3faabcda59a7148e31a32ce403805a5 100644 (file)
@@ -28,7 +28,6 @@
 #include <linux/delay.h>
 #include <linux/phy/omap_control_phy.h>
 #include <linux/of_platform.h>
-#include <linux/spinlock.h>
 
 #define        PLL_STATUS              0x00000004
 #define        PLL_GO                  0x00000008
@@ -83,10 +82,6 @@ struct ti_pipe3 {
        struct clk              *refclk;
        struct clk              *div_clk;
        struct pipe3_dpll_map   *dpll_map;
-       bool                    enabled;
-       spinlock_t              lock;   /* serialize clock enable/disable */
-       /* the below flag is needed specifically for SATA */
-       bool                    refclk_enabled;
 };
 
 static struct pipe3_dpll_map dpll_map_usb[] = {
@@ -137,6 +132,9 @@ static struct pipe3_dpll_params *ti_pipe3_get_dpll_params(struct ti_pipe3 *phy)
        return NULL;
 }
 
+static int ti_pipe3_enable_clocks(struct ti_pipe3 *phy);
+static void ti_pipe3_disable_clocks(struct ti_pipe3 *phy);
+
 static int ti_pipe3_power_off(struct phy *x)
 {
        struct ti_pipe3 *phy = phy_get_drvdata(x);
@@ -217,6 +215,7 @@ static int ti_pipe3_init(struct phy *x)
        u32 val;
        int ret = 0;
 
+       ti_pipe3_enable_clocks(phy);
        /*
         * Set pcie_pcs register to 0x96 for proper functioning of phy
         * as recommended in AM572x TRM SPRUHZ6, section 18.5.2.2, table
@@ -250,33 +249,35 @@ static int ti_pipe3_exit(struct phy *x)
        u32 val;
        unsigned long timeout;
 
-       /* SATA DPLL can't be powered down due to Errata i783 and PCIe
-        * does not have internal DPLL
-        */
-       if (of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-sata") ||
-           of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-pcie"))
+       /* SATA DPLL can't be powered down due to Errata i783 */
+       if (of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-sata"))
                return 0;
 
-       /* Put DPLL in IDLE mode */
-       val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
-       val |= PLL_IDLE;
-       ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
-
-       /* wait for LDO and Oscillator to power down */
-       timeout = jiffies + msecs_to_jiffies(PLL_IDLE_TIME);
-       do {
-               cpu_relax();
-               val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_STATUS);
-               if ((val & PLL_TICOPWDN) && (val & PLL_LDOPWDN))
-                       break;
-       } while (!time_after(jiffies, timeout));
+       /* PCIe doesn't have internal DPLL */
+       if (!of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-pcie")) {
+               /* Put DPLL in IDLE mode */
+               val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
+               val |= PLL_IDLE;
+               ti_pipe3_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
 
-       if (!(val & PLL_TICOPWDN) || !(val & PLL_LDOPWDN)) {
-               dev_err(phy->dev, "Failed to power down: PLL_STATUS 0x%x\n",
-                       val);
-               return -EBUSY;
+               /* wait for LDO and Oscillator to power down */
+               timeout = jiffies + msecs_to_jiffies(PLL_IDLE_TIME);
+               do {
+                       cpu_relax();
+                       val = ti_pipe3_readl(phy->pll_ctrl_base, PLL_STATUS);
+                       if ((val & PLL_TICOPWDN) && (val & PLL_LDOPWDN))
+                               break;
+               } while (!time_after(jiffies, timeout));
+
+               if (!(val & PLL_TICOPWDN) || !(val & PLL_LDOPWDN)) {
+                       dev_err(phy->dev, "Failed to power down: PLL_STATUS 0x%x\n",
+                               val);
+                       return -EBUSY;
+               }
        }
 
+       ti_pipe3_disable_clocks(phy);
+
        return 0;
 }
 static struct phy_ops ops = {
@@ -306,7 +307,6 @@ static int ti_pipe3_probe(struct platform_device *pdev)
                return -ENOMEM;
 
        phy->dev                = &pdev->dev;
-       spin_lock_init(&phy->lock);
 
        if (!of_device_is_compatible(node, "ti,phy-pipe3-pcie")) {
                match = of_match_device(ti_pipe3_id_table, &pdev->dev);
@@ -402,6 +402,10 @@ static int ti_pipe3_probe(struct platform_device *pdev)
 
        platform_set_drvdata(pdev, phy);
        pm_runtime_enable(phy->dev);
+       /* Prevent auto-disable of refclk for SATA PHY due to Errata i783 */
+       if (of_device_is_compatible(node, "ti,phy-pipe3-sata"))
+               if (!IS_ERR(phy->refclk))
+                       clk_prepare_enable(phy->refclk);
 
        generic_phy = devm_phy_create(phy->dev, NULL, &ops);
        if (IS_ERR(generic_phy))
@@ -413,63 +417,33 @@ static int ti_pipe3_probe(struct platform_device *pdev)
        if (IS_ERR(phy_provider))
                return PTR_ERR(phy_provider);
 
-       pm_runtime_get(&pdev->dev);
-
        return 0;
 }
 
 static int ti_pipe3_remove(struct platform_device *pdev)
 {
-       if (!pm_runtime_suspended(&pdev->dev))
-               pm_runtime_put(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
 
        return 0;
 }
 
-#ifdef CONFIG_PM
-static int ti_pipe3_enable_refclk(struct ti_pipe3 *phy)
+static int ti_pipe3_enable_clocks(struct ti_pipe3 *phy)
 {
-       if (!IS_ERR(phy->refclk) && !phy->refclk_enabled) {
-               int ret;
+       int ret = 0;
 
+       if (!IS_ERR(phy->refclk)) {
                ret = clk_prepare_enable(phy->refclk);
                if (ret) {
                        dev_err(phy->dev, "Failed to enable refclk %d\n", ret);
                        return ret;
                }
-               phy->refclk_enabled = true;
        }
 
-       return 0;
-}
-
-static void ti_pipe3_disable_refclk(struct ti_pipe3 *phy)
-{
-       if (!IS_ERR(phy->refclk))
-               clk_disable_unprepare(phy->refclk);
-
-       phy->refclk_enabled = false;
-}
-
-static int ti_pipe3_enable_clocks(struct ti_pipe3 *phy)
-{
-       int ret = 0;
-       unsigned long flags;
-
-       spin_lock_irqsave(&phy->lock, flags);
-       if (phy->enabled)
-               goto err1;
-
-       ret = ti_pipe3_enable_refclk(phy);
-       if (ret)
-               goto err1;
-
        if (!IS_ERR(phy->wkupclk)) {
                ret = clk_prepare_enable(phy->wkupclk);
                if (ret) {
                        dev_err(phy->dev, "Failed to enable wkupclk %d\n", ret);
-                       goto err2;
+                       goto disable_refclk;
                }
        }
 
@@ -477,96 +451,33 @@ static int ti_pipe3_enable_clocks(struct ti_pipe3 *phy)
                ret = clk_prepare_enable(phy->div_clk);
                if (ret) {
                        dev_err(phy->dev, "Failed to enable div_clk %d\n", ret);
-                       goto err3;
+                       goto disable_wkupclk;
                }
        }
 
-       phy->enabled = true;
-       spin_unlock_irqrestore(&phy->lock, flags);
        return 0;
 
-err3:
+disable_wkupclk:
        if (!IS_ERR(phy->wkupclk))
                clk_disable_unprepare(phy->wkupclk);
 
-err2:
+disable_refclk:
        if (!IS_ERR(phy->refclk))
                clk_disable_unprepare(phy->refclk);
 
-       ti_pipe3_disable_refclk(phy);
-err1:
-       spin_unlock_irqrestore(&phy->lock, flags);
        return ret;
 }
 
 static void ti_pipe3_disable_clocks(struct ti_pipe3 *phy)
 {
-       unsigned long flags;
-
-       spin_lock_irqsave(&phy->lock, flags);
-       if (!phy->enabled) {
-               spin_unlock_irqrestore(&phy->lock, flags);
-               return;
-       }
-
        if (!IS_ERR(phy->wkupclk))
                clk_disable_unprepare(phy->wkupclk);
-       /* Don't disable refclk for SATA PHY due to Errata i783 */
-       if (!of_device_is_compatible(phy->dev->of_node, "ti,phy-pipe3-sata"))
-               ti_pipe3_disable_refclk(phy);
+       if (!IS_ERR(phy->refclk))
+               clk_disable_unprepare(phy->refclk);
        if (!IS_ERR(phy->div_clk))
                clk_disable_unprepare(phy->div_clk);
-       phy->enabled = false;
-       spin_unlock_irqrestore(&phy->lock, flags);
-}
-
-static int ti_pipe3_runtime_suspend(struct device *dev)
-{
-       struct ti_pipe3 *phy = dev_get_drvdata(dev);
-
-       ti_pipe3_disable_clocks(phy);
-       return 0;
 }
 
-static int ti_pipe3_runtime_resume(struct device *dev)
-{
-       struct ti_pipe3 *phy = dev_get_drvdata(dev);
-       int ret = 0;
-
-       ret = ti_pipe3_enable_clocks(phy);
-       return ret;
-}
-
-static int ti_pipe3_suspend(struct device *dev)
-{
-       struct ti_pipe3 *phy = dev_get_drvdata(dev);
-
-       ti_pipe3_disable_clocks(phy);
-       return 0;
-}
-
-static int ti_pipe3_resume(struct device *dev)
-{
-       struct ti_pipe3 *phy = dev_get_drvdata(dev);
-       int ret;
-
-       ret = ti_pipe3_enable_clocks(phy);
-       if (ret)
-               return ret;
-
-       pm_runtime_disable(dev);
-       pm_runtime_set_active(dev);
-       pm_runtime_enable(dev);
-       return 0;
-}
-#endif
-
-static const struct dev_pm_ops ti_pipe3_pm_ops = {
-       SET_RUNTIME_PM_OPS(ti_pipe3_runtime_suspend,
-                          ti_pipe3_runtime_resume, NULL)
-       SET_SYSTEM_SLEEP_PM_OPS(ti_pipe3_suspend, ti_pipe3_resume)
-};
-
 static const struct of_device_id ti_pipe3_id_table[] = {
        {
                .compatible = "ti,phy-usb3",
@@ -592,7 +503,6 @@ static struct platform_driver ti_pipe3_driver = {
        .remove         = ti_pipe3_remove,
        .driver         = {
                .name   = "ti-pipe3",
-               .pm     = &ti_pipe3_pm_ops,
                .of_match_table = ti_pipe3_id_table,
        },
 };