From mboxrd@z Thu Jan 1 00:00:00 1970 From: Sinan Kaya Subject: [PATCH V3 0/3] dmaengine: qcom_hidma: add error reporting Date: Tue, 23 Aug 2016 00:48:08 -0400 Message-ID: <1471927691-28827-1-git-send-email-okaya@codeaurora.org> Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:50098 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932638AbcHWEsT (ORCPT ); Tue, 23 Aug 2016 00:48:19 -0400 Sender: linux-arm-msm-owner@vger.kernel.org List-Id: linux-arm-msm@vger.kernel.org To: dmaengine@vger.kernel.org, timur@codeaurora.org, cov@codeaurora.org, vinod.koul@intel.com, jcm@redhat.com Cc: agross@codeaurora.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, Sinan Kaya Three changes: 1. There is a race condition between data transfer callback and descriptor free code. The callback routine may decide to clear the resources even though the descriptor has not yet been freed. 2. DMA Engine framework now supports direct error reporting to the client via the callback. Pass the DMA errors to the client by passing a result argument. The HW only supports a generic error when something goes wrong. That's why, using DMA_TRANS_ABORTED all the time. 3. The HIDMA driver is capable of error detection. However, the error was not being passed back to the client when tx_status API is called. ------------------------ Changes from v2 (https://patchwork.kernel.org/patch/9253379/) ------------------------ - Implement the error passing to the client. - Get rid of the reset in the interrupt handler when an error happens and put the HW into disabled state. The only way to recover is for the client to terminate the channel. Sinan Kaya (3): dmaengine: qcom_hidma: release the descriptor before the callback dmaengine: qcom_hidma: report transfer errors with new interface dmaengine: qcom_hidma: add error reporting for tx_status drivers/dma/qcom/hidma.c | 50 +++++++++++++++++++++++++++++++++++---------- drivers/dma/qcom/hidma.h | 1 + drivers/dma/qcom/hidma_ll.c | 32 +++++++---------------------- 3 files changed, 47 insertions(+), 36 deletions(-) -- 1.8.2.1 From mboxrd@z Thu Jan 1 00:00:00 1970 From: okaya@codeaurora.org (Sinan Kaya) Date: Tue, 23 Aug 2016 00:48:08 -0400 Subject: [PATCH V3 0/3] dmaengine: qcom_hidma: add error reporting Message-ID: <1471927691-28827-1-git-send-email-okaya@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Three changes: 1. There is a race condition between data transfer callback and descriptor free code. The callback routine may decide to clear the resources even though the descriptor has not yet been freed. 2. DMA Engine framework now supports direct error reporting to the client via the callback. Pass the DMA errors to the client by passing a result argument. The HW only supports a generic error when something goes wrong. That's why, using DMA_TRANS_ABORTED all the time. 3. The HIDMA driver is capable of error detection. However, the error was not being passed back to the client when tx_status API is called. ------------------------ Changes from v2 (https://patchwork.kernel.org/patch/9253379/) ------------------------ - Implement the error passing to the client. - Get rid of the reset in the interrupt handler when an error happens and put the HW into disabled state. The only way to recover is for the client to terminate the channel. Sinan Kaya (3): dmaengine: qcom_hidma: release the descriptor before the callback dmaengine: qcom_hidma: report transfer errors with new interface dmaengine: qcom_hidma: add error reporting for tx_status drivers/dma/qcom/hidma.c | 50 +++++++++++++++++++++++++++++++++++---------- drivers/dma/qcom/hidma.h | 1 + drivers/dma/qcom/hidma_ll.c | 32 +++++++---------------------- 3 files changed, 47 insertions(+), 36 deletions(-) -- 1.8.2.1