From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B61A5C433E9 for ; Mon, 21 Dec 2020 12:35:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 83EAE224D3 for ; Mon, 21 Dec 2020 12:35:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726746AbgLUMfH (ORCPT ); Mon, 21 Dec 2020 07:35:07 -0500 Received: from so254-31.mailgun.net ([198.61.254.31]:45434 "EHLO so254-31.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726614AbgLUMfH (ORCPT ); Mon, 21 Dec 2020 07:35:07 -0500 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1608554088; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=tDvl9tDLfGJ7JN2lYUJAQJ9Ss9Zsrq4uuuiex7ki2+Q=; b=WiAc5hhdA+tAw6IlO1Zgv5rOK8WqyKXOv1+uSzgQvaW720IgB2Sma/8r56hoMfQUn7Zq9lcf m3agyUIyGhH3ESRxdH9C5xicqb7IsFunporaES/gKumiG6zDncmV/3l5H8cj2VsAipzHB6OI XRhA2qwUxBHg/Tw8G6MdG4mPCd8= X-Mailgun-Sending-Ip: 198.61.254.31 X-Mailgun-Sid: WyI5ZGU3NiIsICJsaW51eC1pMmNAdmdlci5rZXJuZWwub3JnIiwgImJlOWU0YSJd Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n08.prod.us-west-2.postgun.com with SMTP id 5fe09646cfe5dd67dbcda5b5 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Mon, 21 Dec 2020 12:34:14 GMT Sender: rojay=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id 8FFD3C433ED; Mon, 21 Dec 2020 12:34:14 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: rojay) by smtp.codeaurora.org (Postfix) with ESMTPSA id 4CAD8C433C6; Mon, 21 Dec 2020 12:34:13 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Mon, 21 Dec 2020 18:04:13 +0530 From: rojay@codeaurora.org To: Akash Asthana Cc: wsa@kernel.org, swboyd@chromium.org, dianders@chromium.org, saiprakash.ranjan@codeaurora.org, gregkh@linuxfoundation.org, mka@chromium.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 Subject: Re: [RESEND PATCH V6 1/2] i2c: i2c-qcom-geni: Store DMA mapping data in geni_i2c_dev struct In-Reply-To: <049c28e9-1211-377f-941d-ba169645dd24@codeaurora.org> References: <20201203103156.32595-1-rojay@codeaurora.org> <20201203103156.32595-2-rojay@codeaurora.org> <049c28e9-1211-377f-941d-ba169645dd24@codeaurora.org> Message-ID: <585a9b7ab44e3a99eb803536af6334e5@codeaurora.org> X-Sender: rojay@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-i2c@vger.kernel.org On 2020-12-09 18:29, Akash Asthana wrote: > Hi Roja, > > On 12/3/2020 4:01 PM, Roja Rani Yarubandi wrote: >> Store DMA mapping data in geni_i2c_dev struct to enhance DMA mapping >> data scope. For example during shutdown callback to unmap DMA mapping, >> this stored DMA mapping data can be used to call geni_se_tx_dma_unprep >> and geni_se_rx_dma_unprep functions. >> >> Add two helper functions geni_i2c_rx_msg_cleanup and >> geni_i2c_tx_msg_cleanup 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. >> >> Signed-off-by: Roja Rani Yarubandi >> --- >> Changes in V5: >> - As per Stephen's comments separated this patch from shutdown >> callback patch, gi2c->cur = NULL is not removed from >> geni_i2c_abort_xfer(), and made a copy of gi2c->cur and passed >> to cleanup functions. >> >> Changes in V6: >> - Added spin_lock/unlock in geni_i2c_rx_msg_cleanup() and >> geni_i2c_tx_msg_cleanup() functions. >> >> drivers/i2c/busses/i2c-qcom-geni.c | 69 >> +++++++++++++++++++++++------- >> 1 file changed, 53 insertions(+), 16 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-qcom-geni.c >> b/drivers/i2c/busses/i2c-qcom-geni.c >> index dce75b85253c..bfbc80f65006 100644 >> --- a/drivers/i2c/busses/i2c-qcom-geni.c >> +++ b/drivers/i2c/busses/i2c-qcom-geni.c >> @@ -86,6 +86,9 @@ struct geni_i2c_dev { >> u32 clk_freq_out; >> const struct geni_i2c_clk_fld *clk_fld; >> int suspended; >> + void *dma_buf; >> + size_t xfer_len; >> + dma_addr_t dma_addr; >> }; >> struct geni_i2c_err_log { >> @@ -348,14 +351,49 @@ static void geni_i2c_tx_fsm_rst(struct >> geni_i2c_dev *gi2c) >> dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n"); >> } >> +static void geni_i2c_rx_msg_cleanup(struct geni_i2c_dev *gi2c, >> + struct i2c_msg *cur) >> +{ >> + struct geni_se *se = &gi2c->se; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&gi2c->lock, flags); >> + gi2c->cur_rd = 0; >> + if (gi2c->dma_buf) { >> + if (gi2c->err) >> + geni_i2c_rx_fsm_rst(gi2c); > > Which race we are trying to avoid here by holding spinlock? > Thought that race might occur with "cur" here. > We cannot call any sleeping API by holding spinlock, > geni_i2c_rx_fsm_rst calls *wait-for-completion*, which is a sleeping > call. > Fixed this. >> + geni_se_rx_dma_unprep(se, gi2c->dma_addr, gi2c->xfer_len); >> + i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err); >> + } >> + spin_unlock_irqrestore(&gi2c->lock, flags); >> +} >> + >> +static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c, >> + struct i2c_msg *cur) >> +{ >> + struct geni_se *se = &gi2c->se; >> + unsigned long flags; >> + >> + spin_lock_irqsave(&gi2c->lock, flags); >> + gi2c->cur_wr = 0; >> + if (gi2c->dma_buf) { >> + if (gi2c->err) >> + geni_i2c_tx_fsm_rst(gi2c); > > Same here > > Regards, > > Akash > >> + geni_se_tx_dma_unprep(se, gi2c->dma_addr, gi2c->xfer_len); >> + i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err); >> + } >> + spin_unlock_irqrestore(&gi2c->lock, flags); >> +} >> + >> static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct >> i2c_msg *msg, >> u32 m_param) >> { >> - dma_addr_t rx_dma; >> + dma_addr_t rx_dma = 0; >> unsigned long time_left; >> void *dma_buf = NULL; >> struct geni_se *se = &gi2c->se; >> size_t len = msg->len; >> + struct i2c_msg *cur; >> if (!of_machine_is_compatible("lenovo,yoga-c630")) >> dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); >> @@ -372,19 +410,18 @@ static int geni_i2c_rx_one_msg(struct >> geni_i2c_dev *gi2c, struct i2c_msg *msg, >> geni_se_select_mode(se, GENI_SE_FIFO); >> i2c_put_dma_safe_msg_buf(dma_buf, msg, false); >> dma_buf = NULL; >> + } else { >> + gi2c->xfer_len = len; >> + gi2c->dma_addr = rx_dma; >> + gi2c->dma_buf = dma_buf; >> } >> + cur = gi2c->cur; >> time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); >> if (!time_left) >> geni_i2c_abort_xfer(gi2c); >> - gi2c->cur_rd = 0; >> - if (dma_buf) { >> - if (gi2c->err) >> - geni_i2c_rx_fsm_rst(gi2c); >> - geni_se_rx_dma_unprep(se, rx_dma, len); >> - i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); >> - } >> + geni_i2c_rx_msg_cleanup(gi2c, cur); >> return gi2c->err; >> } >> @@ -392,11 +429,12 @@ static int geni_i2c_rx_one_msg(struct >> geni_i2c_dev *gi2c, struct i2c_msg *msg, >> static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct >> i2c_msg *msg, >> u32 m_param) >> { >> - dma_addr_t tx_dma; >> + dma_addr_t tx_dma = 0; >> unsigned long time_left; >> void *dma_buf = NULL; >> struct geni_se *se = &gi2c->se; >> size_t len = msg->len; >> + struct i2c_msg *cur; >> if (!of_machine_is_compatible("lenovo,yoga-c630")) >> dma_buf = i2c_get_dma_safe_msg_buf(msg, 32); >> @@ -413,22 +451,21 @@ static int geni_i2c_tx_one_msg(struct >> geni_i2c_dev *gi2c, struct i2c_msg *msg, >> geni_se_select_mode(se, GENI_SE_FIFO); >> i2c_put_dma_safe_msg_buf(dma_buf, msg, false); >> dma_buf = NULL; >> + } else { >> + gi2c->xfer_len = len; >> + gi2c->dma_addr = tx_dma; >> + gi2c->dma_buf = dma_buf; >> } >> if (!dma_buf) /* Get FIFO IRQ */ >> writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG); >> + cur = gi2c->cur; >> time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT); >> if (!time_left) >> geni_i2c_abort_xfer(gi2c); >> - gi2c->cur_wr = 0; >> - if (dma_buf) { >> - if (gi2c->err) >> - geni_i2c_tx_fsm_rst(gi2c); >> - geni_se_tx_dma_unprep(se, tx_dma, len); >> - i2c_put_dma_safe_msg_buf(dma_buf, msg, !gi2c->err); >> - } >> + geni_i2c_tx_msg_cleanup(gi2c, cur); >> return gi2c->err; >> }