omap_hsmmc: prevent races with irq handler
commit4dffd7a251172d78a157ff45ec1207012f44774a
authorAdrian Hunter <adrian.hunter@nokia.com>
Tue, 22 Sep 2009 23:44:58 +0000 (22 16:44 -0700)
committerLinus Torvalds <torvalds@linux-foundation.org>
Wed, 23 Sep 2009 14:39:35 +0000 (23 07:39 -0700)
tree35db86950a7c43ba4b69dc64220c57d10e15f693
parent23050103c21d4d5314b7c978187e6e4305a00495
omap_hsmmc: prevent races with irq handler

If an unexpected interrupt occurs while preparing the next request, an
oops can occur.

For example, a new request is setting up DMA for data transfer so
host->data is not NULL.  An unexpected transfer complete (TC) interrupt
comes along and the interrupt handler sets host->data to NULL.  Oops!

Prevent that by adding a spinlock.

Signed-off-by: Adrian Hunter <adrian.hunter@nokia.com>
Acked-by: Matt Fleming <matt@console-pimps.org>
Cc: Ian Molton <ian@mnementh.co.uk>
Cc: "Roberto A. Foglietta" <roberto.foglietta@gmail.com>
Cc: Jarkko Lavinen <jarkko.lavinen@nokia.com>
Cc: Denis Karpov <ext-denis.2.karpov@nokia.com>
Cc: Pierre Ossman <pierre@ossman.eu>
Cc: Philip Langdale <philipl@overt.org>
Cc: "Madhusudhan" <madhu.cr@ti.com>
Cc: <linux-mmc@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
drivers/mmc/host/omap_hsmmc.c