From mboxrd@z Thu Jan 1 00:00:00 1970 From: santosh.shilimkar@ti.com (Santosh Shilimkar) Date: Sun, 28 Oct 2012 09:41:05 +0530 Subject: [PATCH] i2c: omap: ensure writes to dev->buf_len are ordered In-Reply-To: References: <1351155648-20429-1-git-send-email-balbi@ti.com> <508BBC59.60504@ti.com> Message-ID: <508CB059.8000203@ti.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Saturday 27 October 2012 09:29 PM, Paul Walmsley wrote: > On Sat, 27 Oct 2012, Santosh Shilimkar wrote: > >> Another alternative, which I will recommend to just make use of the >> read*/wrire* instead __raw versions. The barriers are taken care >> already and driver point of view, it is transparent. > > Those barriers will disappear if CONFIG_ARM_DMA_MEM_BUFFERABLE is set to > N, so that's probably not the right thing to do in this case. The barrier > here isn't DMA-related, it's needed due to the design of the driver. > Good point. > In fact the wmb() is probably overkill, since only a compiler reordering > barrier is needed. It can probably just be barrier(). > I agree. Just barrier() is enough to avoid compiler re-ordering. Regards Santosh