[PATCH] mmc: tmio: Fix hang during suspend

From: Geert Uytterhoeven
Date: Thu Aug 14 2014 - 11:24:17 EST


On R-Car Gen 2, the SDHI registers cannot be accessed while the SDHI
module clock is disabled. Doing so will cause a lock-up.

When suspending, enable the module clock before disabling the SDHI
interrupts, and disable the clock again afterwards.

This fixes suspend and resume on r8a7791/koelsch.

Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
drivers/mmc/host/tmio_mmc_pio.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index faf0924e71cb..83192420a7e3 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -1147,8 +1147,18 @@ int tmio_mmc_host_suspend(struct device *dev)
{
struct mmc_host *mmc = dev_get_drvdata(dev);
struct tmio_mmc_host *host = mmc_priv(mmc);
+ struct tmio_mmc_data *pdata = host->pdata;
+
+ if (pdata->clk_enable) {
+ unsigned int f;
+ pdata->clk_enable(host->pdev, &f);
+ }

tmio_mmc_disable_mmc_irqs(host, TMIO_MASK_ALL);
+
+ if (pdata->clk_disable)
+ pdata->clk_disable(host->pdev);
+
return 0;
}
EXPORT_SYMBOL(tmio_mmc_host_suspend);
--
1.9.1

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