[PATCH 2/2] sunxi-mci: Fix hang on boot caused by irq storm

[Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>]

On power up / reboot sometimes the mmc controller will have its irq line
asserted. Getting this de-asserted requires enabling the clocks and then
resetting the mmc controller.

Signed-off-by: Hans de Goede <hdegoede-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
---
 drivers/mmc/host/sunxi-mci.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/mmc/host/sunxi-mci.c b/drivers/mmc/host/sunxi-mci.c
index 0eb59be..8b47c99 100644
--- a/drivers/mmc/host/sunxi-mci.c
+++ b/drivers/mmc/host/sunxi-mci.c
@@ -737,13 +737,6 @@ static int sunxi_mmc_resource_request(struct sunxi_mmc_host *host,
 	if (IS_ERR(host->reg_base))
 		return PTR_ERR(host->reg_base);
 
-	host->irq = platform_get_irq(pdev, 0);
-	ret = devm_request_irq(&pdev->dev, host->irq, sunxi_mmc_irq, 0,
-			       "sunxi-mci", host);
-	if (ret)
-		return ret;
-	disable_irq(host->irq);
-
 	host->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
 	if (IS_ERR(host->clk_ahb)) {
 		dev_err(&pdev->dev, "Could not get ahb clock\n");
@@ -756,7 +749,21 @@ static int sunxi_mmc_resource_request(struct sunxi_mmc_host *host,
 		return PTR_ERR(host->clk_mod);
 	}
 
-	return 0;
+	/* Make sure the controller is in a sane state before enabling irqs */
+	ret = sunxi_mmc_init_host(host->mmc);
+	if (ret)
+		return ret;
+
+	host->irq = platform_get_irq(pdev, 0);
+	ret = devm_request_irq(&pdev->dev, host->irq, sunxi_mmc_irq, 0,
+			       "sunxi-mci", host);
+	if (ret == 0)
+		disable_irq(host->irq);
+
+	/* And put it back in reset */
+	sunxi_mmc_exit_host(host);
+
+	return ret;
 }
 
 static int sunxi_mmc_probe(struct platform_device *pdev)
-- 
1.8.4.2