[PATCH 1/2] mmc: bcm2835: reset host on timeout

[Michal Suchanek]

The bcm2835 mmc host tends to lock up for unknown reason so reset it on
timeout. The upper mmc block layer tries retransimitting with single
blocks which tends to work out after a long wait.

This is better than giving up and leaving the machine broken for no
obvious reason.

Signed-off-by: Michal Suchanek <msuchanek at suse.de>
---
 drivers/mmc/host/bcm2835.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/mmc/host/bcm2835.c b/drivers/mmc/host/bcm2835.c
index 229dc18f0581..ce05fe72f865 100644
--- a/drivers/mmc/host/bcm2835.c
+++ b/drivers/mmc/host/bcm2835.c
@@ -286,6 +286,7 @@ static void bcm2835_reset(struct mmc_host *mmc)
 
 	if (host->dma_chan)
 		dmaengine_terminate_sync(host->dma_chan);
+	host->dma_chan = NULL;
 	bcm2835_reset_internal(host);
 }
 
@@ -837,6 +838,8 @@ static void bcm2835_timeout(struct work_struct *work)
 		dev_err(dev, "timeout waiting for hardware interrupt.\n");
 		bcm2835_dumpregs(host);
 
+		bcm2835_reset(host->mmc);
+
 		if (host->data) {
 			host->data->error = -ETIMEDOUT;
 			bcm2835_finish_data(host);
-- 
2.13.6