[PATCH 6/8] spi: stm32: add runtime PM support

From: Amelie Delaunay
Date: Fri Jun 23 2017 - 08:56:47 EST


This patch reworks suspend and resume callbacks and add runtime_suspend
and runtime_resume callbacks.

Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
---
drivers/spi/spi-stm32.c | 43 ++++++++++++++++++++++++++++++++++++-------
1 file changed, 36 insertions(+), 7 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index 72efc63..209afda 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -27,6 +27,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_platform.h>
+#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/spi/spi.h>

@@ -1164,6 +1165,9 @@ static int stm32_spi_probe(struct platform_device *pdev)
if (spi->dma_tx || spi->dma_rx)
master->can_dma = stm32_spi_can_dma;

+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
ret = devm_spi_register_master(&pdev->dev, master);
if (ret) {
dev_err(&pdev->dev, "spi master registration failed: %d\n",
@@ -1203,6 +1207,8 @@ static int stm32_spi_probe(struct platform_device *pdev)
dma_release_channel(spi->dma_tx);
if (spi->dma_rx)
dma_release_channel(spi->dma_rx);
+
+ pm_runtime_disable(&pdev->dev);
err_clk_disable:
clk_disable_unprepare(spi->clk);
err_master_put:
@@ -1225,23 +1231,42 @@ static int stm32_spi_remove(struct platform_device *pdev)

clk_disable_unprepare(spi->clk);

+ pm_runtime_disable(&pdev->dev);
+
return 0;
}

+#ifdef CONFIG_PM
+static int stm32_spi_runtime_suspend(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct stm32_spi *spi = spi_master_get_devdata(master);
+
+ clk_disable_unprepare(spi->clk);
+
+ return 0;
+}
+
+static int stm32_spi_runtime_resume(struct device *dev)
+{
+ struct spi_master *master = dev_get_drvdata(dev);
+ struct stm32_spi *spi = spi_master_get_devdata(master);
+
+ return clk_prepare_enable(spi->clk);
+}
+#endif
+
#ifdef CONFIG_PM_SLEEP
static int stm32_spi_suspend(struct device *dev)
{
struct spi_master *master = dev_get_drvdata(dev);
- struct stm32_spi *spi = spi_master_get_devdata(master);
int ret;

ret = spi_master_suspend(master);
if (ret)
return ret;

- clk_disable_unprepare(spi->clk);
-
- return ret;
+ return pm_runtime_force_suspend(dev);
}

static int stm32_spi_resume(struct device *dev)
@@ -1250,9 +1275,10 @@ static int stm32_spi_resume(struct device *dev)
struct stm32_spi *spi = spi_master_get_devdata(master);
int ret;

- ret = clk_prepare_enable(spi->clk);
+ ret = pm_runtime_force_resume(dev);
if (ret)
return ret;
+
ret = spi_master_resume(master);
if (ret)
clk_disable_unprepare(spi->clk);
@@ -1261,8 +1287,11 @@ static int stm32_spi_resume(struct device *dev)
}
#endif

-static SIMPLE_DEV_PM_OPS(stm32_spi_pm_ops,
- stm32_spi_suspend, stm32_spi_resume);
+static const struct dev_pm_ops stm32_spi_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(stm32_spi_suspend, stm32_spi_resume)
+ SET_RUNTIME_PM_OPS(stm32_spi_runtime_suspend,
+ stm32_spi_runtime_resume, NULL)
+};

static struct platform_driver stm32_spi_driver = {
.probe = stm32_spi_probe,
--
1.9.1