Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Michal Suchanek <msuchanek@suse.de>
To:     Ulf Hansson <ulf.hansson@linaro.org>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Ray Jui <rjui@broadcom.com>,
        Scott Branden <sbranden@broadcom.com>,
        bcm-kernel-feedback-list@broadcom.com,
        Eric Anholt <eric@anholt.net>,
        Stefan Wahren <stefan.wahren@i2se.com>,
        Michal Suchanek <msuchanek@suse.de>,
        Gerd Hoffmann <kraxel@redhat.com>,
        "Gustavo A. R. Silva" <garsilva@embeddedor.com>,
        Julia Lawall <Julia.Lawall@lip6.fr>, linux-mmc@vger.kernel.org,
        linux-rpi-kernel@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
Subject: [PATCH 1/2] mmc: bcm2835: reset host on timeout
Date:   Wed, 14 Feb 2018 15:38:57 +0100
Message-Id: <97593d6e1a41af1baff61f7d9e6e68a450fc9da6.1518619058.git.msuchanek@suse.de>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

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@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