[PATCH 4/8] spi: pl022: Don't ignore power domain and amba bus at system suspend

Ulf Hansson ulf.hansson at linaro.org
Sat Mar 1 05:56:07 EST 2014


Previously only the resources controlled by the driver were put into
low power state at system suspend. Both the amba bus and a potential
power domain were ignored.

Moreover, while putting the device into low power state we first
brought it back to full power, but for no particular reason.

To handle both issues above, use pm_runtime_force_suspend|resume() from
the system suspend|resume callbacks.

Cc: Mark Brown <broonie at kernel.org>
Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>
---
 drivers/spi/spi-pl022.c |   54 ++++++++++++++++-------------------------------
 1 file changed, 18 insertions(+), 36 deletions(-)

diff --git a/drivers/spi/spi-pl022.c b/drivers/spi/spi-pl022.c
index 6dfcabf..d37e840 100644
--- a/drivers/spi/spi-pl022.c
+++ b/drivers/spi/spi-pl022.c
@@ -2277,35 +2277,7 @@ pl022_remove(struct amba_device *adev)
 	return 0;
 }
 
-#ifdef CONFIG_PM
-/*
- * These two functions are used from both suspend/resume and
- * the runtime counterparts to handle external resources like
- * clocks, pins and regulators when going to sleep.
- */
-static void pl022_suspend_resources(struct pl022 *pl022, bool runtime)
-{
-	clk_disable_unprepare(pl022->clk);
-
-	if (runtime)
-		pinctrl_pm_select_idle_state(&pl022->adev->dev);
-	else
-		pinctrl_pm_select_sleep_state(&pl022->adev->dev);
-}
-
-static void pl022_resume_resources(struct pl022 *pl022, bool runtime)
-{
-	/* First go to the default state */
-	pinctrl_pm_select_default_state(&pl022->adev->dev);
-	if (!runtime)
-		/* Then let's idle the pins until the next transfer happens */
-		pinctrl_pm_select_idle_state(&pl022->adev->dev);
-
-	clk_prepare_enable(pl022->clk);
-}
-#endif
-
-#ifdef CONFIG_SUSPEND
+#ifdef CONFIG_PM_SLEEP
 static int pl022_suspend(struct device *dev)
 {
 	struct pl022 *pl022 = dev_get_drvdata(dev);
@@ -2317,8 +2289,13 @@ static int pl022_suspend(struct device *dev)
 		return ret;
 	}
 
-	pm_runtime_get_sync(dev);
-	pl022_suspend_resources(pl022, false);
+	ret = pm_runtime_force_suspend(dev);
+	if (ret) {
+		spi_master_resume(pl022->master);
+		return ret;
+	}
+
+	pinctrl_pm_select_sleep_state(dev);
 
 	dev_dbg(dev, "suspended\n");
 	return 0;
@@ -2329,8 +2306,9 @@ static int pl022_resume(struct device *dev)
 	struct pl022 *pl022 = dev_get_drvdata(dev);
 	int ret;
 
-	pl022_resume_resources(pl022, false);
-	pm_runtime_put(dev);
+	ret = pm_runtime_force_resume(dev);
+	if (ret)
+		dev_err(dev, "problem resuming\n");
 
 	/* Start the queue running */
 	ret = spi_master_resume(pl022->master);
@@ -2341,14 +2319,16 @@ static int pl022_resume(struct device *dev)
 
 	return ret;
 }
-#endif	/* CONFIG_PM */
+#endif
 
 #ifdef CONFIG_PM
 static int pl022_runtime_suspend(struct device *dev)
 {
 	struct pl022 *pl022 = dev_get_drvdata(dev);
 
-	pl022_suspend_resources(pl022, true);
+	clk_disable_unprepare(pl022->clk);
+	pinctrl_pm_select_idle_state(dev);
+
 	return 0;
 }
 
@@ -2356,7 +2336,9 @@ static int pl022_runtime_resume(struct device *dev)
 {
 	struct pl022 *pl022 = dev_get_drvdata(dev);
 
-	pl022_resume_resources(pl022, true);
+	pinctrl_pm_select_default_state(dev);
+	clk_prepare_enable(pl022->clk);
+
 	return 0;
 }
 #endif
-- 
1.7.9.5




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