[PATCH 4/5] spi: stm32: fixes suspend/resume management

From: Alain Volmat
Date: Fri Aug 07 2020 - 09:25:40 EST


From: Amelie Delaunay <amelie.delaunay@xxxxxx>

This patch adds pinctrl power management, and reconfigure spi controller
in case of resume.

Fixes: 038ac869c9d2 ("spi: stm32: add runtime PM support")

Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
Signed-off-by: Alain Volmat <alain.volmat@xxxxxx>
---
drivers/spi/spi-stm32.c | 27 ++++++++++++++++++++++++---
1 file changed, 24 insertions(+), 3 deletions(-)

diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c
index bdd4e70c3f10..e196dbc5c432 100644
--- a/drivers/spi/spi-stm32.c
+++ b/drivers/spi/spi-stm32.c
@@ -13,6 +13,7 @@
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/of_platform.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/pm_runtime.h>
#include <linux/reset.h>
#include <linux/spi/spi.h>
@@ -2004,6 +2005,8 @@ static int stm32_spi_remove(struct platform_device *pdev)

pm_runtime_disable(&pdev->dev);

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

@@ -2015,13 +2018,18 @@ static int stm32_spi_runtime_suspend(struct device *dev)

clk_disable_unprepare(spi->clk);

- return 0;
+ return pinctrl_pm_select_sleep_state(dev);
}

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);
+ int ret;
+
+ ret = pinctrl_pm_select_default_state(dev);
+ if (ret)
+ return ret;

return clk_prepare_enable(spi->clk);
}
@@ -2051,10 +2059,23 @@ static int stm32_spi_resume(struct device *dev)
return ret;

ret = spi_master_resume(master);
- if (ret)
+ if (ret) {
clk_disable_unprepare(spi->clk);
+ return ret;
+ }

- return ret;
+ ret = pm_runtime_get_sync(dev);
+ if (ret) {
+ dev_err(dev, "Unable to power device:%d\n", ret);
+ return ret;
+ }
+
+ spi->cfg->config(spi);
+
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return 0;
}
#endif

--
2.7.4