From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from devils.ext.ti.com ([198.47.26.153]) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1Vm0Ja-0001tN-Np for linux-mtd@lists.infradead.org; Thu, 28 Nov 2013 12:03:27 +0000 Message-ID: <529730F2.5070807@ti.com> Date: Thu, 28 Nov 2013 17:32:58 +0530 From: Sourav Poddar MIME-Version: 1.0 To: Mark Brown Subject: Re: [PATCH 12/17] spi/qspi: convert driver to enable/disable memory mapped. References: <1385451313-1875-1-git-send-email-sourav.poddar@ti.com> <1385451313-1875-13-git-send-email-sourav.poddar@ti.com> <20131126131138.GJ14725@sirena.org.uk> <5296D37C.2020003@ti.com> <20131128104922.GK14725@sirena.org.uk> <5297242B.3040807@ti.com> <20131128115934.GE27568@sirena.org.uk> In-Reply-To: <20131128115934.GE27568@sirena.org.uk> Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Cc: devicetree@vger.kernel.org, computersforpeace@gmail.com, balbi@ti.com, linux-spi@vger.kernel.org, linux-mtd@lists.infradead.org, bcousson@baylibre.com, linux-omap@vger.kernel.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Thursday 28 November 2013 05:29 PM, Mark Brown wrote: > On Thu, Nov 28, 2013 at 04:38:27PM +0530, Sourav Poddar wrote: >> On Thursday 28 November 2013 04:19 PM, Mark Brown wrote: >>> Removing the mapping isn't going to stop another context which has >>> obtained a handle on the map trying to look at the mapping. >> hmm..so the 'memcpy' part should be made atomic.(if possible?). > Or holding the memory region should prevent normal SPI use (so any users > ought to drop the memory region when they don't need it). hmm.ok i will unmap the memory region when not in use. > I'm still a bit surprised there's no DMA controllers for this... Yes, but thats the truth :(