[PATCH 1/2] phy: ti-pipe3: Disable clocks on system suspend

From: Roger Quadros
Date: Fri Dec 19 2014 - 07:05:36 EST


On system suspend, the runtime_suspend() driver hook doesn't get
called 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.

Add suspend/resume hooks to the driver.
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.

Move enabling/disabling clock code into helper functions.

Reported-by: Nishant Menon <nm@xxxxxx>
Signed-off-by: Roger Quadros <rogerq@xxxxxx>
---
drivers/phy/phy-ti-pipe3.c | 99 +++++++++++++++++++++++++++++++++++-----------
1 file changed, 77 insertions(+), 22 deletions(-)

diff --git a/drivers/phy/phy-ti-pipe3.c b/drivers/phy/phy-ti-pipe3.c
index 1387b4d..e60ff14 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
@@ -83,6 +84,8 @@ struct ti_pipe3 {
struct clk *div_clk;
struct pipe3_dpll_map *dpll_map;
u8 id;
+ bool enabled;
+ spinlock_t lock; /* serialize clock enable/disable */
};

static struct pipe3_dpll_map dpll_map_usb[] = {
@@ -303,6 +306,7 @@ 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),
@@ -425,24 +429,14 @@ 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);
@@ -467,6 +461,9 @@ static int ti_pipe3_runtime_resume(struct device *dev)
goto err3;
}
}
+
+ phy->enabled = true;
+ spin_unlock_irqrestore(&phy->lock, flags);
return 0;

err3:
@@ -478,19 +475,77 @@ 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[] = {
{
@@ -518,7 +573,7 @@ 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),
},
};
--
2.1.0

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