From: Ulf Hansson <ulf.hansson@linaro.org>
Date: Sun, 8 Sep 2019 12:12:27 +0200
Subject: mmc: dw_mmc: Re-store SDIO IRQs mask at system resume
Git-commit: 7c526608d5afb62cbc967225e2ccaacfdd142e9d
Patch-mainline: 5.4-rc1
References: bnc#1151927 5.3.4

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: Jiri Slaby <jslaby@suse.cz>
---
 drivers/mmc/host/dw_mmc.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -3460,6 +3460,10 @@ int dw_mci_runtime_resume(struct device
 	/* 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);