From patchwork Fri Oct 30 14:59:59 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Roja Rani Yarubandi X-Patchwork-Id: 11869989 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id B8672157C for ; Fri, 30 Oct 2020 15:00:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9D99B22241 for ; Fri, 30 Oct 2020 15:00:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727056AbgJ3PAz (ORCPT ); Fri, 30 Oct 2020 11:00:55 -0400 Received: from alexa-out.qualcomm.com ([129.46.98.28]:15998 "EHLO alexa-out.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726779AbgJ3PAn (ORCPT ); Fri, 30 Oct 2020 11:00:43 -0400 Received: from ironmsg-lv-alpha.qualcomm.com ([10.47.202.13]) by alexa-out.qualcomm.com with ESMTP; 30 Oct 2020 08:00:43 -0700 X-QCInternal: smtphost Received: from ironmsg02-blr.qualcomm.com ([10.86.208.131]) by ironmsg-lv-alpha.qualcomm.com with ESMTP/TLS/AES256-SHA; 30 Oct 2020 08:00:41 -0700 X-QCInternal: smtphost Received: from c-rojay-linux.qualcomm.com ([10.206.21.80]) by ironmsg02-blr.qualcomm.com with ESMTP; 30 Oct 2020 20:30:08 +0530 Received: by c-rojay-linux.qualcomm.com (Postfix, from userid 88981) id 21BEE26B6; Fri, 30 Oct 2020 20:30:07 +0530 (IST) From: Roja Rani Yarubandi To: wsa@kernel.org Cc: swboyd@chromium.org, dianders@chromium.org, saiprakash.ranjan@codeaurora.org, gregkh@linuxfoundation.org, mka@chromium.org, akashast@codeaurora.org, msavaliy@qti.qualcomm.com, skakit@codeaurora.org, vkaur@codeaurora.org, pyarlaga@codeaurora.org, rnayak@codeaurora.org, agross@kernel.org, bjorn.andersson@linaro.org, linux-arm-msm@vger.kernel.org, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, sumit.semwal@linaro.org, linux-media@vger.kernel.org, Roja Rani Yarubandi Subject: [PATCH V6 3/3] i2c: i2c-qcom-geni: Add shutdown callback for i2c Date: Fri, 30 Oct 2020 20:29:59 +0530 Message-Id: <20201030145959.505-4-rojay@codeaurora.org> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20201030145959.505-1-rojay@codeaurora.org> References: <20201030145959.505-1-rojay@codeaurora.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org If the hardware is still accessing memory after SMMU translation is disabled (as part of smmu shutdown callback), then the IOVAs (I/O virtual address) which it was using will go on the bus as the physical addresses which will result in unknown crashes like NoC/interconnect errors. So, implement shutdown callback to i2c driver to stop on-going transfer and unmap DMA mappings during system "reboot" or "shutdown". Fixes: 37692de5d523 ("i2c: i2c-qcom-geni: Add bus driver for the Qualcomm GENI I2C controller") Signed-off-by: Roja Rani Yarubandi --- Changes in V2: - As per Stephen's comments added seperate function for stop transfer, fixed minor nitpicks. - As per Stephen's comments, changed commit text. Changes in V3: - As per Stephen's comments, squashed patch 1 into patch 2, added Fixes tag. - As per Akash's comments, included FIFO case in stop_xfer, fixed minor nitpicks. Changes in V4: - As per Stephen's comments cleaned up geni_i2c_stop_xfer function, added dma_buf in geni_i2c_dev struct to call i2c_put_dma_safe_msg_buf() from other functions, removed "iova" check in geni_se_rx_dma_unprep() and geni_se_tx_dma_unprep() functions. - Added two helper functions geni_i2c_rx_one_msg_done() and geni_i2c_tx_one_msg_done() to unwrap the things after rx/tx FIFO/DMA transfers, so that the same can be used in geni_i2c_stop_xfer() function during shutdown callback. Updated commit text accordingly. - Checking whether it is tx/rx transfer using I2C_M_RD which is valid for both FIFO and DMA cases, so dropped DMA_RX_ACTIVE and DMA_TX_ACTIVE bit checking Changes in V5: - As per Stephen's comments, added spin_lock_irqsave & spin_unlock_irqsave in geni_i2c_stop_xfer() function. Changes in V6: - As per Stephen's comments, taken care of unsafe lock order in geni_i2c_stop_xfer(). - Moved spin_lock/unlock to geni_i2c_rx_msg_cleanup() and geni_i2c_tx_msg_cleanup() functions. drivers/i2c/busses/i2c-qcom-geni.c | 35 ++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) diff --git a/drivers/i2c/busses/i2c-qcom-geni.c b/drivers/i2c/busses/i2c-qcom-geni.c index e3a4ae88ed31..0c35e3e27a01 100644 --- a/drivers/i2c/busses/i2c-qcom-geni.c +++ b/drivers/i2c/busses/i2c-qcom-geni.c @@ -385,6 +385,33 @@ static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c, spin_unlock_irqrestore(&gi2c->lock, flags); } +static void geni_i2c_stop_xfer(struct geni_i2c_dev *gi2c) +{ + int ret; + u32 geni_status; + struct i2c_msg *cur; + + /* Resume device, as runtime suspend can happen anytime during transfer */ + ret = pm_runtime_get_sync(gi2c->se.dev); + if (ret < 0) { + dev_err(gi2c->se.dev, "Failed to resume device: %d\n", ret); + return; + } + + geni_status = readl_relaxed(gi2c->se.base + SE_GENI_STATUS); + if (!(geni_status & M_GENI_CMD_ACTIVE)) + goto out; + + cur = gi2c->cur; + geni_i2c_abort_xfer(gi2c); + if (cur->flags & I2C_M_RD) + geni_i2c_rx_msg_cleanup(gi2c, cur); + else + geni_i2c_tx_msg_cleanup(gi2c, cur); +out: + pm_runtime_put_sync_suspend(gi2c->se.dev); +} + static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg, u32 m_param) { @@ -666,6 +693,13 @@ static int geni_i2c_remove(struct platform_device *pdev) return 0; } +static void geni_i2c_shutdown(struct platform_device *pdev) +{ + struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev); + + geni_i2c_stop_xfer(gi2c); +} + static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev) { int ret; @@ -730,6 +764,7 @@ MODULE_DEVICE_TABLE(of, geni_i2c_dt_match); static struct platform_driver geni_i2c_driver = { .probe = geni_i2c_probe, .remove = geni_i2c_remove, + .shutdown = geni_i2c_shutdown, .driver = { .name = "geni_i2c", .pm = &geni_i2c_pm_ops,