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* [PATCH 1/1] dw_mmc: insmod followed by rmmod will hung for eMMC
@ 2015-05-18 14:23 Prabu Thangamuthu
  2015-05-22 13:21 ` Ulf Hansson
  0 siblings, 1 reply; 4+ messages in thread
From: Prabu Thangamuthu @ 2015-05-18 14:23 UTC (permalink / raw)
  To: Seungwon Jeon, Jaehoon Chung, Ulf Hansson,
	linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org
  Cc: Manjunath M Bettegowda, prabu.t@synopsys.com

Removing dw_mmc driver immediately after inserting the dw_mmc driver is 
getting hung for eMMC device. Root cause for this issue is, dw_mci_remove
will disable all the interrupts then it will call dw_mci_cleanup_slot.
dw_mci_cleanup_slot is issuing CMD6 to disable boot partition access and
it's waiting for command complete interrupt. Since INTMASK was already
cleared by dw_mci_remove, command complete interrupt is not reaching 
the system. This leads to process hung.

Signed-off-by: Prabu Thangamuthu <prabu.t@synopsys.com>
---
 drivers/mmc/host/dw_mmc.c |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/mmc/host/dw_mmc.c b/drivers/mmc/host/dw_mmc.c
index 5f5adaf..f0a0aff 100644
--- a/drivers/mmc/host/dw_mmc.c
+++ b/drivers/mmc/host/dw_mmc.c
@@ -2941,15 +2941,15 @@ void dw_mci_remove(struct dw_mci *host)
 {
 	int i;
 
-	mci_writel(host, RINTSTS, 0xFFFFFFFF);
-	mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
-
 	for (i = 0; i < host->num_slots; i++) {
 		dev_dbg(host->dev, "remove slot %d\n", i);
 		if (host->slot[i])
 			dw_mci_cleanup_slot(host->slot[i], i);
 	}
 
+	mci_writel(host, RINTSTS, 0xFFFFFFFF);
+	mci_writel(host, INTMASK, 0); /* disable all mmc interrupt first */
+
 	/* disable clock to CIU */
 	mci_writel(host, CLKENA, 0);
 	mci_writel(host, CLKSRC, 0);
-- 
1.7.6.5

^ permalink raw reply related	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2015-05-27  5:15 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2015-05-18 14:23 [PATCH 1/1] dw_mmc: insmod followed by rmmod will hung for eMMC Prabu Thangamuthu
2015-05-22 13:21 ` Ulf Hansson
2015-05-27  1:50   ` Jaehoon Chung
2015-05-27  5:15     ` Prabu Thangamuthu

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