From mboxrd@z Thu Jan 1 00:00:00 1970 From: Vinod Koul Subject: Re: [PATCH] dmaengine: qcom_hidma: release the descriptor before the callback Date: Fri, 19 Aug 2016 22:32:08 +0530 Message-ID: <20160819170208.GC9343@localhost> References: <20160808090203.GY9681@localhost> <21475c6e-a5f8-5125-3998-f3995ce67c4d@codeaurora.org> <20160810172805.GH9681@localhost> <20160819024853.GR9681@localhost> <8c096fee-9749-a7df-7e04-25d21c0ea9ac@codeaurora.org> <20160819034249.GS9681@localhost> <3592cfe2-a563-7c26-9a9e-925051cc1934@codeaurora.org> <20160819055252.GT9681@localhost> <37b059dcb67d1c83c2193acecef0ab96@codeaurora.org> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <37b059dcb67d1c83c2193acecef0ab96@codeaurora.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: okaya@codeaurora.org Cc: linux-arm-msm@vger.kernel.org, timur@codeaurora.org, Russell King - ARM Linux , linux-kernel@vger.kernel.org, Christopher Covington , dmaengine@vger.kernel.org, linux-arm-kernel@lists.infradead.org List-Id: linux-arm-msm@vger.kernel.org On Fri, Aug 19, 2016 at 07:13:43AM -0400, okaya@codeaurora.org wrote: > On 2016-08-19 01:52, Vinod Koul wrote: > >On Thu, Aug 18, 2016 at 11:48:52PM -0400, Sinan Kaya wrote: > >>On 8/18/2016 11:42 PM, Vinod Koul wrote: > >>> On Thu, Aug 18, 2016 at 11:26:28PM -0400, Sinan Kaya wrote: > >>>> On 8/18/2016 10:48 PM, Vinod Koul wrote: > >>>>>> Keep a size limited list with error cookies and flush them in terminate all? > >>>>> I think so, terminate_all anyway cleans up the channel. Btw what is the > >>>>> behaviour on error? Do you terminate or somthing else? > >>>>> > >>>> > >>>> On error, I flush all outstanding transactions with an error code and I reset > >>>> the channel. After the reset, the DMA channel is functional again. The client > >>>> doesn't need to shutdown anything. > >>> > >>> You mean from the client context or driver? > >>> > >> > >>The client doesn't need to call device_free_chan_resources and > >>device_terminate_all > >>to be specific. Client can certainly call these if it needs to > >>but it is not > >>required to recover the channel. > > > >You didn't answer my question! > > > >On error you said you flush, so who does that? > > This is done by the driver in interrupt context when an error > interrupt is received. All transactions are posted and hw is reset. Hmmm, waht about the txn which are pending? DO you clear them..? -- ~Vinod