[RFC PATCH v1 4/6] spi: rockchip: Suspend and resume the bus during NOIRQ_SYSTEM_SLEEP_PM ops

From: Jon Lin
Date: Thu Feb 10 2022 - 22:50:01 EST


From: shengfei Xu <xsf@xxxxxxxxxxxxxx>

the wakeup interrupt handler which is guaranteed not to run while
@resume noirq() is being executed. the patch can help to avoid the
wakeup source try to access spi when the spi is in suspend mode.

Signed-off-by: shengfei Xu <xsf@xxxxxxxxxxxxxx>
Signed-off-by: Jon Lin <jon.lin@xxxxxxxxxxxxxx>
---

drivers/spi/spi-rockchip.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)

diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c
index 5f6a70664871..5457af616a44 100644
--- a/drivers/spi/spi-rockchip.c
+++ b/drivers/spi/spi-rockchip.c
@@ -959,14 +959,14 @@ static int rockchip_spi_suspend(struct device *dev)
{
int ret;
struct spi_controller *ctlr = dev_get_drvdata(dev);
+ struct rockchip_spi *rs = spi_controller_get_devdata(ctlr);

ret = spi_controller_suspend(ctlr);
if (ret < 0)
return ret;

- ret = pm_runtime_force_suspend(dev);
- if (ret < 0)
- return ret;
+ clk_disable_unprepare(rs->spiclk);
+ clk_disable_unprepare(rs->apb_pclk);

pinctrl_pm_select_sleep_state(dev);

@@ -981,10 +981,14 @@ static int rockchip_spi_resume(struct device *dev)

pinctrl_pm_select_default_state(dev);

- ret = pm_runtime_force_resume(dev);
+ ret = clk_prepare_enable(rs->apb_pclk);
if (ret < 0)
return ret;

+ ret = clk_prepare_enable(rs->spiclk);
+ if (ret < 0)
+ clk_disable_unprepare(rs->apb_pclk);
+
ret = spi_controller_resume(ctlr);
if (ret < 0) {
clk_disable_unprepare(rs->spiclk);
@@ -1026,7 +1030,7 @@ static int rockchip_spi_runtime_resume(struct device *dev)
#endif /* CONFIG_PM */

static const struct dev_pm_ops rockchip_spi_pm = {
- SET_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(rockchip_spi_suspend, rockchip_spi_resume)
SET_RUNTIME_PM_OPS(rockchip_spi_runtime_suspend,
rockchip_spi_runtime_resume, NULL)
};
--
2.17.1