[v2,02/11] mmc: dw_mmc: Re-store SDIO IRQs mask at system resume

Message ID 20190908101236.2802-3-ulf.hansson@linaro.org
State New
Headers show
Series
  • mmc: core: PM fixes/improvements for SDIO IRQs
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Commit Message

Ulf Hansson Sept. 8, 2019, 10:12 a.m.
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>

---
 drivers/mmc/host/dw_mmc.c | 4 ++++
 1 file changed, 4 insertions(+)

-- 
2.17.1

Comments

Doug Anderson Sept. 9, 2019, 10:32 p.m. | #1
Hi,

On Sun, Sep 8, 2019 at 3:12 AM Ulf Hansson <ulf.hansson@linaro.org> wrote:
>

> 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>

> ---

>  drivers/mmc/host/dw_mmc.c | 4 ++++

>  1 file changed, 4 insertions(+)


Reviewed-by: Douglas Anderson <dianders@chromium.org>

Patch

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index eea52e2c5a0c..79c55c7b4afd 100644
--- 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 *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);