From patchwork Sun Mar 24 17:49:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867633 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DBCBB922 for ; Sun, 24 Mar 2019 17:50:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id C3F4928870 for ; Sun, 24 Mar 2019 17:50:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id B469E2913A; Sun, 24 Mar 2019 17:50:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 4CCD628870 for ; Sun, 24 Mar 2019 17:50:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=BNYK2IktDz6SlUvD89sCQeJlv1OwzYa0NTlp3Weca/M=; b=mJD7ALxesvs3V4B17eFXikX8Zl GC8CUbNdvezW13NIPJ+5DjCM5eIwO372b2nf6bUvlhOjkpUkCQ7qXyE7aA6rYGGxZlyNPw0IDMnyr YfZq1KigO8T090ZV3igAgcV7swR4WgYQ+LbR/vKi+veLaRFucUVfjlkpEG/T8I6K1uAjZYP+9Gz0g XODJHB+SnEzjdWK6rSvmieeOIk5oZEimann7bQFZMaLpaDAIF7yvVRjga8uDiuaxDZE8opPTioQBk EFBn/bQcvq5/iBlHK4R3z28sXcWtC8pxNSXJBUUZYaNI15Uz75RmOBzQ3upU99S48OxNsqpA2QDwK jMi9JH3g==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87Gd-0007tL-6O; Sun, 24 Mar 2019 17:50:43 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87GI-0007UD-LE; Sun, 24 Mar 2019 17:50:24 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759425; Sun, 24 Mar 2019 17:50:10 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 1/9] spi: bcm2835aux: unifying code between polling and interrupt driven code Date: Sun, 24 Mar 2019 17:49:54 +0000 Message-Id: <20190324175002.28969-2-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105023_038934_9818396F X-CRM114-Status: GOOD ( 11.54 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl Sharing more code between polling and interrupt-driven mode. Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 51 ++++++++++++++++---------------------------- 1 file changed, 18 insertions(+), 33 deletions(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index f7e054848ca5..41366d0a16af 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -178,23 +178,13 @@ static void bcm2835aux_spi_reset_hw(struct bcm2835aux_spi *bs) BCM2835_AUX_SPI_CNTL0_CLEARFIFO); } -static irqreturn_t bcm2835aux_spi_interrupt(int irq, void *dev_id) +static void bcm2835aux_spi_transfer_helper(struct bcm2835aux_spi *bs) { - struct spi_master *master = dev_id; - struct bcm2835aux_spi *bs = spi_master_get_devdata(master); - irqreturn_t ret = IRQ_NONE; - - /* IRQ may be shared, so return if our interrupts are disabled */ - if (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_CNTL1) & - (BCM2835_AUX_SPI_CNTL1_TXEMPTY | BCM2835_AUX_SPI_CNTL1_IDLE))) - return ret; - /* check if we have data to read */ while (bs->rx_len && (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT) & BCM2835_AUX_SPI_STAT_RX_EMPTY))) { bcm2835aux_rd_fifo(bs); - ret = IRQ_HANDLED; } /* check if we have data to write */ @@ -203,7 +193,6 @@ static irqreturn_t bcm2835aux_spi_interrupt(int irq, void *dev_id) (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT) & BCM2835_AUX_SPI_STAT_TX_FULL))) { bcm2835aux_wr_fifo(bs); - ret = IRQ_HANDLED; } /* and check if we have reached "done" */ @@ -211,8 +200,21 @@ static irqreturn_t bcm2835aux_spi_interrupt(int irq, void *dev_id) (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT) & BCM2835_AUX_SPI_STAT_BUSY))) { bcm2835aux_rd_fifo(bs); - ret = IRQ_HANDLED; } +} + +static irqreturn_t bcm2835aux_spi_interrupt(int irq, void *dev_id) +{ + struct spi_master *master = dev_id; + struct bcm2835aux_spi *bs = spi_master_get_devdata(master); + + /* IRQ may be shared, so return if our interrupts are disabled */ + if (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_CNTL1) & + (BCM2835_AUX_SPI_CNTL1_TXEMPTY | BCM2835_AUX_SPI_CNTL1_IDLE))) + return IRQ_NONE; + + /* do common fifo handling */ + bcm2835aux_spi_transfer_helper(bs); if (!bs->tx_len) { /* disable tx fifo empty interrupt */ @@ -226,8 +228,7 @@ static irqreturn_t bcm2835aux_spi_interrupt(int irq, void *dev_id) complete(&master->xfer_completion); } - /* and return */ - return ret; + return IRQ_HANDLED; } static int __bcm2835aux_spi_transfer_one_irq(struct spi_master *master, @@ -273,7 +274,6 @@ static int bcm2835aux_spi_transfer_one_poll(struct spi_master *master, { struct bcm2835aux_spi *bs = spi_master_get_devdata(master); unsigned long timeout; - u32 stat; /* configure spi */ bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL1, bs->cntl[1]); @@ -284,24 +284,9 @@ static int bcm2835aux_spi_transfer_one_poll(struct spi_master *master, /* loop until finished the transfer */ while (bs->rx_len) { - /* read status */ - stat = bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT); - - /* fill in tx fifo with remaining data */ - if ((bs->tx_len) && (!(stat & BCM2835_AUX_SPI_STAT_TX_FULL))) { - bcm2835aux_wr_fifo(bs); - continue; - } - /* read data from fifo for both cases */ - if (!(stat & BCM2835_AUX_SPI_STAT_RX_EMPTY)) { - bcm2835aux_rd_fifo(bs); - continue; - } - if (!(stat & BCM2835_AUX_SPI_STAT_BUSY)) { - bcm2835aux_rd_fifo(bs); - continue; - } + /* do common fifo handling */ + bcm2835aux_spi_transfer_helper(bs); /* there is still data pending to read check the timeout */ if (bs->rx_len && time_after(jiffies, timeout)) { From patchwork Sun Mar 24 17:49:55 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867635 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C106C922 for ; Sun, 24 Mar 2019 17:51:02 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A6FE028870 for ; Sun, 24 Mar 2019 17:51:02 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 97C832913A; Sun, 24 Mar 2019 17:51:02 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 50E2328870 for ; 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Sun, 24 Mar 2019 17:50:56 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87GL-0007UD-Pz; Sun, 24 Mar 2019 17:50:29 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759423; Sun, 24 Mar 2019 17:50:10 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 2/9] spi: bcm2835aux: remove dangerous uncontrolled read of fifo Date: Sun, 24 Mar 2019 17:49:55 +0000 Message-Id: <20190324175002.28969-3-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105026_326487_062E9787 X-CRM114-Status: UNSURE ( 6.46 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl This read of the fifo is a potential candidate for a race condition as the spi transfer is not necessarily finished and so can lead to an early read of the fifo that still misses data. So it has been removed. Fixes: 1ea29b39f4c812ece2f936065a0a3d6fe44a263e Suggested-by: Hubert Denkmair Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 7 ------- 1 file changed, 7 deletions(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index 41366d0a16af..0838dbda57c7 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -194,13 +194,6 @@ static void bcm2835aux_spi_transfer_helper(struct bcm2835aux_spi *bs) BCM2835_AUX_SPI_STAT_TX_FULL))) { bcm2835aux_wr_fifo(bs); } - - /* and check if we have reached "done" */ - while (bs->rx_len && - (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT) & - BCM2835_AUX_SPI_STAT_BUSY))) { - bcm2835aux_rd_fifo(bs); - } } static irqreturn_t bcm2835aux_spi_interrupt(int irq, void *dev_id) From patchwork Sun Mar 24 17:49:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867637 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1EC6B922 for ; Sun, 24 Mar 2019 17:51:16 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 075BB28870 for ; Sun, 24 Mar 2019 17:51:16 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id EFD7C2913A; Sun, 24 Mar 2019 17:51:15 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A435228870 for ; Sun, 24 Mar 2019 17:51:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=keChGtpjwRGIn11fM1/7eBk+9wuv0hbfhF0jOy4axmk=; b=M5yFfOvAk5m+AYhCnWzWqPe6uQ PFx85bm7NM2wopjpBlXRD5FGo/67C/FIW6djla1/sMfQvoKH1t+DpztGHMkdBlQeR96kSqKNe3ckU y6jHwYU1OmM1bzTxE10xCLR5JykYSBe6KYzsfxYSr097+KHfu/pBrA4qqWGfVC4kO41ktnZNEunvk foJ+5jH9aVTjKw2xqiEbJNpaB6wnpoY7tMXOTNtsRK4wL7yIieemiun0/1RR+nv4p77Xrn1MZoR1e Ym5yjiSs57c5arbxleI2pEVfA6TgBHKhHK7uvPTH5m67nVfVtiVzU2/8pYDVtxzUGKMRYH1b8nNqS cOx8yQNw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87H6-0008WJ-P1; Sun, 24 Mar 2019 17:51:12 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87GQ-0007UD-Bq; Sun, 24 Mar 2019 17:50:34 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759426; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 3/9] spi: bcm2835aux: use BCM2835_AUX_SPI_STAT_RX_LVL Date: Sun, 24 Mar 2019 17:49:56 +0000 Message-Id: <20190324175002.28969-4-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105031_193868_1A23831C X-CRM114-Status: UNSURE ( 9.52 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl On long running tests with a mcp2517fd can controller it showed that on rare occations the data read shows corruptions for longer spi transfers. Example of a 22 byte transfer: expected (as captured on logic analyzer): FF FF 78 00 00 00 08 06 00 00 91 20 77 56 84 85 86 87 88 89 8a 8b read by the driver: FF FF 78 00 00 00 08 06 00 00 91 20 77 56 84 88 89 8a 00 00 8b 9b To fix this use BCM2835_AUX_SPI_STAT_RX_LVL to determine when we may read data from the fifo reliably without any corruption. Surprisingly the only values ever empirically read in BCM2835_AUX_SPI_STAT_RX_LVL are 0x00, 0x10, 0x20 and 0x30. So whenever the mask is not 0 we can read from the fifo in a safe manner. The patch has now been tested intensively and we are no longer able to reproduce the "RX" issue any longer. Fixes: 1ea29b39f4c812ece2f936065a0a3d6fe44a263e Reported-by: Hubert Denkmair Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index 0838dbda57c7..d9e62f717a45 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -180,12 +180,12 @@ static void bcm2835aux_spi_reset_hw(struct bcm2835aux_spi *bs) static void bcm2835aux_spi_transfer_helper(struct bcm2835aux_spi *bs) { + u32 stat = bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT); + /* check if we have data to read */ - while (bs->rx_len && - (!(bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT) & - BCM2835_AUX_SPI_STAT_RX_EMPTY))) { + for (; bs->rx_len && (stat & BCM2835_AUX_SPI_STAT_RX_LVL); + stat = bcm2835aux_rd(bs, BCM2835_AUX_SPI_STAT)) bcm2835aux_rd_fifo(bs); - } /* check if we have data to write */ while (bs->tx_len && From patchwork Sun Mar 24 17:49:57 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867639 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 3380C922 for ; Sun, 24 Mar 2019 17:51:33 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1DAAC28870 for ; Sun, 24 Mar 2019 17:51:33 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0FC0D2913A; Sun, 24 Mar 2019 17:51:33 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id BBCE628870 for ; Sun, 24 Mar 2019 17:51:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=2dTt1FC3sC2TBQ1+NLNVmpT7AJz0WsAOAVq4SrkGUFs=; b=LllrRvHm5ExOjVh5q0Jxnbu2BV I2wa9wkd3nkVI0y/frXsMdR7hX9dizJ4Jp1wmkUT4D074bds08RlZuup5RFYmSAgKDCPdKLl4/b6z SJXC+H53vHiPuXVbcyLiT0dVC0xOxtaOEJHYdBncl3cm6dQvw7np4II/gMbXnuS0ebvy21ofORlBh eQyxAc/DSMEmmmMPk7KvS1w5zETy0ZTA9btD2v8k1aHc8DRwNvTKAoTiDZGnyQoLn39C6gPMKg4cl UbzuMXRiku613t1IJdZ2xnEz3UIzwZCAAUe5beHtLqv22cg+G0Iz2biQvhlt0v8qutvDdGVuc29+e cShwytOA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87HI-0000Lx-Fy; Sun, 24 Mar 2019 17:51:24 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87GV-0007UD-LW; Sun, 24 Mar 2019 17:50:37 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759427; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 4/9] spi: bcm2835aux: remove dead code Date: Sun, 24 Mar 2019 17:49:57 +0000 Message-Id: <20190324175002.28969-5-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105035_957840_FBDDB4E6 X-CRM114-Status: UNSURE ( 5.67 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl Remove dead code that never can get reached, as we limit count to a max of 3. Suggested-by: Hubert Denkmair Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 3 --- 1 file changed, 3 deletions(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index d9e62f717a45..890aca4873a7 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -123,9 +123,6 @@ static inline void bcm2835aux_rd_fifo(struct bcm2835aux_spi *bs) data = bcm2835aux_rd(bs, BCM2835_AUX_SPI_IO); if (bs->rx_buf) { switch (count) { - case 4: - *bs->rx_buf++ = (data >> 24) & 0xff; - /* fallthrough */ case 3: *bs->rx_buf++ = (data >> 16) & 0xff; /* fallthrough */ From patchwork Sun Mar 24 17:49:58 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867645 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id A19E81575 for ; Sun, 24 Mar 2019 17:52:28 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8BA80290DB for ; Sun, 24 Mar 2019 17:52:28 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7C4F82914B; Sun, 24 Mar 2019 17:52:28 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 34B56290DB for ; Sun, 24 Mar 2019 17:52:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=KcG2eVwBH1FCy4yI3iXdmARyaCHUM1r8iKN9N3E9Zko=; b=KMjGBdZEmCiAyJylpSKHSciisY 1nYLuj3c2hqti7QEQ8OuibYqqY7Cpy6ArGfy4/EGDCFF/6tjfNnQikurMRSvIrpvrU6XD//H+aqOC NVNLkqvcjYnJRWm1iTmfGk5857AXBbSfBgZmWW1ZNTcM8w/4rB/gBHXRPGKPpa0SJIxNKT7P7H9tu OBtmphyEcfZVkWbDG8umVcO/oWH6rrBBb2g6BHb8uoHtblG7g1CRWVljJNGd9kPbCaO7fSevM7hlP EqT0l/PsBFVBAhD53vLKDrUzrK6sLyGFfeVO9dtrOYWg2zqFiHWnLx1ufQjwIZ91izD6EaLJjYm10 Ha7skqqA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87IE-0001HP-JY; Sun, 24 Mar 2019 17:52:22 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87GY-0007UD-3v; Sun, 24 Mar 2019 17:50:40 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759420; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 5/9] spi: bcm2835aux: fix driver to not allow 65535 (=-1) cs-gpios Date: Sun, 24 Mar 2019 17:49:58 +0000 Message-Id: <20190324175002.28969-6-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105038_475198_08E77649 X-CRM114-Status: GOOD ( 10.56 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl The original driver by default defines num_chipselects as -1. This actually allicates an array of 65535 entries in of_spi_register_master. There is a side-effect for buggy device trees that (contrary to dt-binding documentation) have no cs-gpio defined. This mode was never supported by the driver due to limitations of native cs and additional code complexity and is explicitly not stated to be implemented. To keep backwards compatibility with such buggy DTs we limit the number of chip_selects to 1, as for all practical purposes it is only ever realistic to use a single chip select in native cs mode without negative side-effects. Fixes: 1ea29b39f4c812ece2f936065a0a3d6fe44a263e Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index 890aca4873a7..c8acde017b6a 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -413,7 +413,18 @@ static int bcm2835aux_spi_probe(struct platform_device *pdev) platform_set_drvdata(pdev, master); master->mode_bits = (SPI_CPOL | SPI_CS_HIGH | SPI_NO_CS); master->bits_per_word_mask = SPI_BPW_MASK(8); - master->num_chipselect = -1; + /* even though the driver never officially supported native CS + * allow a single native CS for legacy DT support purposes when + * no cs-gpio is configured. + * Known limitations for native cs are: + * * multiple chip-selects: cs0-cs2 are all simultaniously asserted + * whenever there is a transfer - this even includes SPI_NO_CS + * * SPI_CS_HIGH: is ignores - cs are always asserted low + * * cs_change: cs is deasserted after each spi_transfer + * * cs_delay_usec: cs is always deasserted one SCK cycle after + * a spi_transfer + */ + master->num_chipselect = 1; master->transfer_one = bcm2835aux_spi_transfer_one; master->handle_err = bcm2835aux_spi_handle_err; master->prepare_message = bcm2835aux_spi_prepare_message; From patchwork Sun Mar 24 17:49:59 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867641 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 81142922 for ; Sun, 24 Mar 2019 17:51:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 697B328870 for ; Sun, 24 Mar 2019 17:51:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5D8F02913A; Sun, 24 Mar 2019 17:51:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 05DA128870 for ; 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Sun, 24 Mar 2019 17:51:40 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87Ga-0007UD-Ui; Sun, 24 Mar 2019 17:50:47 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759428; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 6/9] spi: bcm2835aux: warn in dmesg that native cs is not really supported Date: Sun, 24 Mar 2019 17:49:59 +0000 Message-Id: <20190324175002.28969-7-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105041_477160_11BD9C76 X-CRM114-Status: GOOD ( 12.26 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl From personal bad experience (even as the author of the original driver) it shows that native-cs is "somewhat" supported by the spi bus driver when using a buggy device tree. So make sure that the driver is warning in dmesg about this fact that we are running in a not supported mode that may have surprizing limitations. Signed-off-by: Martin Sperl Fixes: 1ea29b39f4c812ece2f936065a0a3d6fe44a263e --- drivers/spi/spi-bcm2835aux.c | 33 +++++++++++++++++++++++++++++++++ 1 file changed, 33 insertions(+) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index c8acde017b6a..6af07dec5fdc 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -396,6 +396,38 @@ static void bcm2835aux_spi_handle_err(struct spi_master *master, bcm2835aux_spi_reset_hw(bs); } +static int bcm2835aux_spi_setup(struct spi_device *spi) +{ + int ret; + + if (spi->mode & SPI_NO_CS) + return 0; + /* sanity check for native cs */ + if (!gpio_is_valid(spi->cs_gpio)) { + /* for dt-backwards compatibility: only support native on CS0 + * known things not supported with broken native CS: + * * multiple chip-selects: cs0-cs2 are all + * simultaniously asserted whenever there is a transfer + * this even includes SPI_NO_CS + * * SPI_CS_HIGH: cs are always asserted low + * * cs_change: cs is deasserted after each spi_transfer + * * cs_delay_usec: cs is always deasserted one SCK cycle + * after the last transfer + * probably more... + */ + if (spi->chip_select == 0) { + dev_err(&spi->dev, + "native CS is not supported but may work for some use-cases for cs = 0 - please define a valid value cs-gpios in DT for complete feature set\n"); + return 0; + } + dev_err(&spi->dev, + "native CS is not supported for cs > 0 - please define a valid value cs-gpios in DT to enable multiple cs\n"); + return -EINVAL; + } + + return 0; +} + static int bcm2835aux_spi_probe(struct platform_device *pdev) { struct spi_master *master; @@ -425,6 +457,7 @@ static int bcm2835aux_spi_probe(struct platform_device *pdev) * a spi_transfer */ master->num_chipselect = 1; + master->setup = bcm2835aux_spi_setup; master->transfer_one = bcm2835aux_spi_transfer_one; master->handle_err = bcm2835aux_spi_handle_err; master->prepare_message = bcm2835aux_spi_prepare_message; From patchwork Sun Mar 24 17:50:00 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867647 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 69254922 for ; Sun, 24 Mar 2019 17:52:38 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 536F428FBD for ; Sun, 24 Mar 2019 17:52:38 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 47CFE2914B; Sun, 24 Mar 2019 17:52:38 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D7F6D28FBD for ; Sun, 24 Mar 2019 17:52:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=yfLcjFiVAvmpT4Glsa4OqaXrZNrAdQqDBQB8802U0bk=; b=DmU0uxt6ochHuL+PXr6oqCDHNc 4Qxqs9NkKdC9mos58LHAgEHoU/w0eHJj4MCpaSQqD7lkzLpnQAzFlcQz1t71oucUvM7eoum3+0/7D EGWYo4mZ8qj1MLqmZfqmNInVow7KZ1tysBhGAQz/IrsPFLsCZQ1mPTvmIRvap4QSjc1Q11UPQA8br OdbpbADXtPZN0OOJxODyKdct76mtZHFvFWmrVROt40i7VylC7eQZOvmBGg0+1PelaP7vd+lr3Iion lQMiStzmfzeow2k3G3pP1IosruYloTSFBhGQPX4rVnHQCq0AkyPERYlLfkSRdj0WJNTA3/mEsY5tR wOxTI5gA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87IR-0001YG-Cg; Sun, 24 Mar 2019 17:52:35 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87Gi-0007UD-GP; Sun, 24 Mar 2019 17:50:58 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759429; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 7/9] spi: bcm2835aux: setup gpio-cs to output and correct level during setup Date: Sun, 24 Mar 2019 17:50:00 +0000 Message-Id: <20190324175002.28969-8-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105049_390963_B6E7D972 X-CRM114-Status: GOOD ( 10.24 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl Setup gpio-cs to the correct levels during setup and also make the gpio definitely an output GPIO. This is transparently fixing some badly configured DTs in the process where cs-gpio is set but the gpios are still configured with native cs. It also makes 100% sure that the initial CS levels are as expected - especially on systems with devices on a bus with mixed CS_HIGH/CS_LOW settings. Fixes: 1ea29b39f4c812ece2f936065a0a3d6fe44a263e Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index 6af07dec5fdc..dd0446968da6 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -425,7 +425,17 @@ static int bcm2835aux_spi_setup(struct spi_device *spi) return -EINVAL; } - return 0; + /* with gpio-cs set the GPIO to the correct level + * and as output (in case the dt has the gpio not configured + * as output but native cs) + */ + ret = gpio_direction_output(spi->cs_gpio, + (spi->mode & SPI_CS_HIGH) ? 0 : 1); + if (ret) + dev_err(&spi->dev, "could not set gpio %i as output: %i\n", + spi->cs_gpio, ret); + + return ret; } static int bcm2835aux_spi_probe(struct platform_device *pdev) From patchwork Sun Mar 24 17:50:01 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867643 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AFF011575 for ; Sun, 24 Mar 2019 17:52:18 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 96055290DB for ; Sun, 24 Mar 2019 17:52:18 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8490D2914B; Sun, 24 Mar 2019 17:52:18 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 22D69290DB for ; Sun, 24 Mar 2019 17:52:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:MIME-Version:Cc:List-Subscribe: List-Help:List-Post:List-Archive:List-Unsubscribe:List-Id:References: In-Reply-To:Message-Id:Date:Subject:To:From:Reply-To:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Owner; bh=RKvjxqmRC6w5DjokZ/Y7nWpj3mZHsKiDzfCuB+De+40=; b=JienSX/p09lxybLcm1x6O4ph3O GdxAFOdcGrplyVKBy4+baS/xiwHzDubUtKJBHgLTtwkWwpdc/OHYfgibgkNm687p28BlbWZ4ylI0G l19RFEkngP7CPxl2Fzqr9zbPKvI03Abtx7OIuGet+FiZ2ytJY8qL6O91pwYN+OlQcCg34krnceZ/F jrEnEpzHFUiyi9G2s0Zvn+OhicHuwGQ01fj8ZiFL5Lz7Oxm4+YowWxvCKQC4gq+KSBniGxdbCeooe 3YOj2riy8Fd+BeabM3hHFgmSfqOnST7GKmFXHqKWQv1ZiKKT6wCupWzVL9PaA2+GCXaUoLpc21saH AMRjrYcg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87I8-00018i-7v; Sun, 24 Mar 2019 17:52:16 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87Gt-0007UD-M9; Sun, 24 Mar 2019 17:51:35 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759431; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 8/9] spi: bcm2835aux: add driver stats to debugfs Date: Sun, 24 Mar 2019 17:50:01 +0000 Message-Id: <20190324175002.28969-9-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105100_451415_776FE790 X-CRM114-Status: UNSURE ( 8.66 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl To estimate efficiency add statistics on transfer types (polling and interrupt) used to debugfs. Signed-off-by: Martin Sperl --- drivers/spi/spi-bcm2835aux.c | 61 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index dd0446968da6..d2b58060b333 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -21,6 +21,7 @@ #include #include +#include #include #include #include @@ -102,8 +103,57 @@ struct bcm2835aux_spi { int tx_len; int rx_len; int pending; + +#if defined(CONFIG_DEBUG_FS) +#define BCM2835_AUX_INCR(field) ((field)++) + u64 count_transfer_polling; + u64 count_transfer_irq; + u64 count_transfer_irq_after_poll; + + struct dentry *debugfs_dir; +#else +#define BCM2835_AUX_INCR(field) +#endif /* CONFIG_DEBUG_FS */ }; +#if defined(CONFIG_DEBUG_FS) +static void bcm2835aux_debugfs_create(struct bcm2835aux_spi *bs, + const char *dname) +{ + char name[64]; + struct dentry *dir; + + /* get full name */ + snprintf(name, sizeof(name), "spi-bcm2835aux-%s", dname); + + /* the base directory */ + dir = debugfs_create_dir(name, NULL); + bs->debugfs_dir = dir; + + /* the counters */ + debugfs_create_u64("count_transfer_polling", 0444, dir, + &bs->count_transfer_polling); + debugfs_create_u64("count_transfer_irq", 0444, dir, + &bs->count_transfer_irq); + debugfs_create_u64("count_transfer_irq_after_poll", 0444, dir, + &bs->count_transfer_irq_after_poll); +} + +static void bcm2835aux_debugfs_remove(struct bcm2835aux_spi *bs) +{ + debugfs_remove_recursive(bs->debugfs_dir); + bs->debugfs_dir = NULL; +} +#else +static void bcm2835aux_debugfs_create(struct bcm2835aux_spi *bs) +{ +} + +static void bcm2835aux_debugfs_remove(struct bcm2835aux_spi *bs) +{ +} +#endif /* CONFIG_DEBUG_FS */ + static inline u32 bcm2835aux_rd(struct bcm2835aux_spi *bs, unsigned reg) { return readl(bs->regs + reg); @@ -242,6 +292,9 @@ static int bcm2835aux_spi_transfer_one_irq(struct spi_master *master, { struct bcm2835aux_spi *bs = spi_master_get_devdata(master); + /* update statistics */ + BCM2835_AUX_INCR(bs->count_transfer_irq); + /* fill in registers and fifos before enabling interrupts */ bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL1, bs->cntl[1]); bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL0, bs->cntl[0]); @@ -265,6 +318,9 @@ static int bcm2835aux_spi_transfer_one_poll(struct spi_master *master, struct bcm2835aux_spi *bs = spi_master_get_devdata(master); unsigned long timeout; + /* update statistics */ + BCM2835_AUX_INCR(bs->count_transfer_polling); + /* configure spi */ bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL1, bs->cntl[1]); bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL0, bs->cntl[0]); @@ -285,6 +341,7 @@ static int bcm2835aux_spi_transfer_one_poll(struct spi_master *master, jiffies - timeout, bs->tx_len, bs->rx_len); /* forward to interrupt handler */ + BCM2835_AUX_INCR(bs->count_transfer_irq_after_poll); return __bcm2835aux_spi_transfer_one_irq(master, spi, tfr); } @@ -531,6 +588,8 @@ static int bcm2835aux_spi_probe(struct platform_device *pdev) goto out_clk_disable; } + bcm2835aux_debugfs_create(bs, dev_name(&pdev->dev)); + return 0; out_clk_disable: @@ -545,6 +604,8 @@ static int bcm2835aux_spi_remove(struct platform_device *pdev) struct spi_master *master = platform_get_drvdata(pdev); struct bcm2835aux_spi *bs = spi_master_get_devdata(master); + bcm2835aux_debugfs_remove(bs); + bcm2835aux_spi_reset_hw(bs); /* disable the HW block by releasing the clock */ From patchwork Sun Mar 24 17:50:02 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Martin Sperl X-Patchwork-Id: 10867649 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E6FD3922 for ; Sun, 24 Mar 2019 17:53:04 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D3C8A2914B for ; Sun, 24 Mar 2019 17:53:04 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C2E6228FBD; Sun, 24 Mar 2019 17:53:04 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 52F1728FBD for ; Sun, 24 Mar 2019 17:53:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=Kgh0tAyYWQtIL3/nF0xLDgyCzGKxM77EsvxRK1efTIs=; b=cvHDdQ5+N2XqfD mQKfvcLfqRlRUsfjNBzX0ViA6B0QnxOKQq1YekD+VEvu0JOdYEjqbiQ0TRcZ5dA9Ls+SgfBpd5Bjb fjwZgd/Y72TyOfp26b+SRC5NT+V0hckeol1KmIL3JuYT5gvSSh1xDNfXDmd9NgAbpjF3mW/wsAH9l 7MXtpbBeUP+aYHP6Qoydc6/XCFb+ERhtUOv5BaG239Hwx0WiRgyCoHA//7DIKjJSwEZ/HeEa8q1zO syiKb6NB+HSSU0Z1wmMZkh5VDbPYJd43K/pZaMK3OAcjade2CNJaYGZapDpgCxl+oBoOzkAhWlimz VPyKHC7KTi/lSYBWojBg==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87It-0001xR-2b; Sun, 24 Mar 2019 17:53:03 +0000 Received: from 212-186-180-163.static.upcbusiness.at ([212.186.180.163] helo=cgate.sperl.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1h87HU-0007UD-HF; Sun, 24 Mar 2019 17:52:03 +0000 Received: from hc1.intern.sperl.org (account martin@sperl.org [10.10.10.59] verified) by sperl.org (CommuniGate Pro SMTP 6.2.1 _community_) with ESMTPSA id 7759432; Sun, 24 Mar 2019 17:50:11 +0000 From: kernel@martin.sperl.org To: Mark Brown , Eric Anholt , Stefan Wahren , Hubert Denkmair , linux-spi@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH V2 9/9] spi: bcm2835aux: make the polling duration limits configurable Date: Sun, 24 Mar 2019 17:50:02 +0000 Message-Id: <20190324175002.28969-10-kernel@martin.sperl.org> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20190324175002.28969-1-kernel@martin.sperl.org> References: <20190324175002.28969-1-kernel@martin.sperl.org> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190324_105137_451506_0C2315E8 X-CRM114-Status: GOOD ( 11.15 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Martin Sperl Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Martin Sperl Under some circumstances the default 30 us polling limit is not optimal and may lead to long delays because we are waiting on an interrupt. with this patch we have the possibility to influence this policy. So make this limit (in us) configurable via a module parameters (but also modifyable via /sys/modules/...) Signed-off-by: Martin Sperl --- Changelog: V1 -> V2: remove the dependency on a different patchset focused on making cs_change delay configurable --- drivers/spi/spi-bcm2835aux.c | 25 ++++++++++++++----------- 1 file changed, 14 insertions(+), 11 deletions(-) -- 2.11.0 diff --git a/drivers/spi/spi-bcm2835aux.c b/drivers/spi/spi-bcm2835aux.c index d2b58060b333..df065108122b 100644 --- a/drivers/spi/spi-bcm2835aux.c +++ b/drivers/spi/spi-bcm2835aux.c @@ -37,6 +37,12 @@ #include #include +/* define polling limits */ +unsigned int polling_limit_us = 30; +module_param(polling_limit_us, uint, 0664); +MODULE_PARM_DESC(polling_limit_us, + "time in us to run a transfer in polling mode\n"); + /* * spi register defines * @@ -89,10 +95,6 @@ #define BCM2835_AUX_SPI_STAT_BUSY 0x00000040 #define BCM2835_AUX_SPI_STAT_BITCOUNT 0x0000003F -/* timeout values */ -#define BCM2835_AUX_SPI_POLLING_LIMIT_US 30 -#define BCM2835_AUX_SPI_POLLING_JIFFIES 2 - struct bcm2835aux_spi { void __iomem *regs; struct clk *clk; @@ -325,8 +327,8 @@ static int bcm2835aux_spi_transfer_one_poll(struct spi_master *master, bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL1, bs->cntl[1]); bcm2835aux_wr(bs, BCM2835_AUX_SPI_CNTL0, bs->cntl[0]); - /* set the timeout */ - timeout = jiffies + BCM2835_AUX_SPI_POLLING_JIFFIES; + /* set the timeout to at least 2 jiffies */ + timeout = jiffies + 2 + HZ * polling_limit_us / 1000000; /* loop until finished the transfer */ while (bs->rx_len) { @@ -356,8 +358,8 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master, struct spi_transfer *tfr) { struct bcm2835aux_spi *bs = spi_master_get_devdata(master); - unsigned long spi_hz, clk_hz, speed; - unsigned long spi_used_hz; + unsigned long spi_hz, clk_hz, speed, spi_used_hz; + unsigned long hz_per_byte, byte_limit; /* calculate the registers to handle * @@ -401,14 +403,15 @@ static int bcm2835aux_spi_transfer_one(struct spi_master *master, * of Hz per byte per polling limit. E.g., we can transfer 1 byte in * 30 µs per 300,000 Hz of bus clock. */ -#define HZ_PER_BYTE ((9 * 1000000) / BCM2835_AUX_SPI_POLLING_LIMIT_US) + hz_per_byte = polling_limit_us ? (9 * 1000000) / polling_limit_us : 0; + byte_limit = hz_per_byte ? spi_used_hz / hz_per_byte : 1; + /* run in polling mode for short transfers */ - if (tfr->len < spi_used_hz / HZ_PER_BYTE) + if (tfr->len < byte_limit) return bcm2835aux_spi_transfer_one_poll(master, spi, tfr); /* run in interrupt mode for all others */ return bcm2835aux_spi_transfer_one_irq(master, spi, tfr); -#undef HZ_PER_BYTE } static int bcm2835aux_spi_prepare_message(struct spi_master *master,