[PATCH AUTOSEL 5.2 167/185] mmc: dw_mmc: Re-store SDIO IRQs mask at system resume

Sasha Levin
2019-09-22T19:21:06Z

From: Ulf Hansson <ulf.hansson@linaro.org>

[ Upstream commit 7c526608d5afb62cbc967225e2ccaacfdd142e9d ]

In cases when SDIO IRQs have been enabled, runtime suspend is prevented by
the driver. However, this still means dw_mci_runtime_suspend|resume() gets
called during system suspend/resume, via pm_runtime_force_suspend|resume().
This means during system suspend/resume, the register context of the dw_mmc
device most likely loses its register context, even in cases when SDIO IRQs
have been enabled.

To re-enable the SDIO IRQs during system resume, the dw_mmc driver
currently relies on the mmc core to re-enable the SDIO IRQs when it resumes
the SDIO card, but this isn't the recommended solution. Instead, it's
better to deal with this locally in the dw_mmc driver, so let's do that.

Tested-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/mmc/host/dw_mmc.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 60c3a06e3469a..45c3490546839 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -3482,6 +3482,10 @@ int dw_mci_runtime_resume(struct device *dev)
/* Force setup bus to guarantee available clock output */
dw_mci_setup_bus(host->slot, true);

+ /* Re-enable SDIO interrupts. */
+ if (sdio_irq_claimed(host->slot->mmc))
+ __dw_mci_enable_sdio_irq(host->slot, 1);
+
/* Now that slots are all setup, we can enable card detect */
dw_mci_enable_cd(host);

--
2.20.1