tree c8146848269f29b5a610eb749f8d78452eabd813
parent a0006477c6af2b0b9b59beb6695d469ebb48f9b2
author Atsushi Nemoto <atsushi.nemoto@sord.co.jp> 1588943568 +0900
committer Greg Kroah-Hartman <gregkh@linuxfoundation.org> 1591528676 +0200

i2c: altera: Fix race between xfer_msg and isr thread

[ Upstream commit 5d4c7977499a736f3f80826bdc9744344ad55589 ]

Use a mutex to protect access to idev->msg_len, idev->buf, etc. which
are modified by both altr_i2c_xfer_msg() and altr_i2c_isr().

This is the minimal fix for easy backporting. A cleanup to remove the
spinlock will be added later.

Signed-off-by: Atsushi Nemoto <atsushi.nemoto@sord.co.jp>
Acked-by: Thor Thayer <thor.thayer@linux.intel.com>
[wsa: updated commit message]
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>