phy: ti-pipe3: Disable clocks on system suspend

On system suspend, the runtime_suspend() driver hook doesn't get
called for USB phy and so the clocks are not disabled in the driver.
This causes the L3INIT_960M_GFCLK and L3INIT_480M_GFCLK to remain
active on the DRA7 platform while in system suspend.

In case of pcie-phy, the runtime_suspend hook gets called after
the suspend hook so we introduce a flag phy->enabled to keep
track if our clocks are enabled or not to prevent multiple
enable/disables.

Add suspend/resume hooks to the driver.
Move enabling/disabling clock code into helper functions.

Reported-by: Nishant Menon <nm@ti.com>
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

1 files changed, 77 insertions, 22 deletions

diff --git a/drivers/phy/phy-ti-pipe3.c b/drivers/phy/phy-ti-pipe3.c
index 465de2c800f2..8c854685a1a7 100644
--- a/drivers/phy/phy-ti-pipe3.c
+++ b/drivers/phy/phy-ti-pipe3.c
@@ -28,6 +28,7 @@
 #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
@@ -82,6 +83,8 @@ 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 */
 };
 
 static struct pipe3_dpll_map dpll_map_usb[] = {
@@ -307,6 +310,7 @@ 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(of_match_ptr(ti_pipe3_id_table),
@@ -427,24 +431,14 @@ static int ti_pipe3_remove(struct platform_device *pdev)
 
 #ifdef CONFIG_PM
 
-static int ti_pipe3_runtime_suspend(struct device *dev)
+static int ti_pipe3_enable_clocks(struct ti_pipe3 *phy)
 {
-        struct ti_pipe3 *phy = dev_get_drvdata(dev);
-
-        if (!IS_ERR(phy->wkupclk))
-                clk_disable_unprepare(phy->wkupclk);
-        if (!IS_ERR(phy->refclk))
-                clk_disable_unprepare(phy->refclk);
-        if (!IS_ERR(phy->div_clk))
-                clk_disable_unprepare(phy->div_clk);
-
-        return 0;
-}
+        int ret = 0;
+        unsigned long flags;
 
-static int ti_pipe3_runtime_resume(struct device *dev)
-{
-        u32 ret = 0;
-        struct ti_pipe3 *phy = dev_get_drvdata(dev);
+        spin_lock_irqsave(&phy->lock, flags);
+        if (phy->enabled)
+                goto err1;
 
         if (!IS_ERR(phy->refclk)) {
                 ret = clk_prepare_enable(phy->refclk);
@@ -469,6 +463,9 @@ static int ti_pipe3_runtime_resume(struct device *dev)
                         goto err3;
                 }
         }
+
+        phy->enabled = true;
+        spin_unlock_irqrestore(&phy->lock, flags);
         return 0;
 
 err3:
@@ -480,19 +477,77 @@ err2:
                 clk_disable_unprepare(phy->refclk);
 
 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);
+        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)
 };
 
-#define DEV_PM_OPS     (&ti_pipe3_pm_ops)
-#else
-#define DEV_PM_OPS     NULL
-#endif
-
 #ifdef CONFIG_OF
 static const struct of_device_id ti_pipe3_id_table[] = {
         {
@@ -520,7 +575,7 @@ static struct platform_driver ti_pipe3_driver = {
         .remove         = ti_pipe3_remove,
         .driver         = {
                 .name   = "ti-pipe3",
-                .pm     = DEV_PM_OPS,
+                .pm     = &ti_pipe3_pm_ops,
                 .of_match_table = of_match_ptr(ti_pipe3_id_table),
         },
 };