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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=ham 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 B15C9C4360C for ; Mon, 12 Apr 2021 09:01:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8A68A61248 for ; Mon, 12 Apr 2021 09:01:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238733AbhDLJB6 (ORCPT ); Mon, 12 Apr 2021 05:01:58 -0400 Received: from mail.kernel.org ([198.145.29.99]:49694 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238808AbhDLI5u (ORCPT ); Mon, 12 Apr 2021 04:57:50 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2BFD061221; Mon, 12 Apr 2021 08:56:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1618217816; bh=Gs8Mok6pUNRSTlJ+vELUt1S67amvbgujMW3lkWone0k=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=zlggXExZGHzgn+zC927W0kBeZHB6FiddxPKZxDKgVVKBVfL2ZYHj35LZ5L3YB2cdp aLZYqvJKRVw+MMfbbyZDXShzxUbTRJq2Bm14DyBHLA2aF43jW1gh9qk1USdWguA5Vo 5j9h8r8JzltfO06uudugdVqukL+QxUy/8VDBeZco= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tim Harvey , Gerhard Bertelsmann , Marc Kleine-Budde , Sasha Levin Subject: [PATCH 5.10 155/188] can: mcp251x: fix support for half duplex SPI host controllers Date: Mon, 12 Apr 2021 10:41:09 +0200 Message-Id: <20210412084018.780508685@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210412084013.643370347@linuxfoundation.org> References: <20210412084013.643370347@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Marc Kleine-Budde [ Upstream commit 617085fca6375e2c1667d1fbfc6adc4034c85f04 ] Some SPI host controllers do not support full-duplex SPI transfers. The function mcp251x_spi_trans() does a full duplex transfer. It is used in several places in the driver, where a TX half duplex transfer is sufficient. To fix support for half duplex SPI host controllers, this patch introduces a new function mcp251x_spi_write() and changes all callers that do a TX half duplex transfer to use mcp251x_spi_write(). Fixes: e0e25001d088 ("can: mcp251x: add support for half duplex controllers") Link: https://lore.kernel.org/r/20210330100246.1074375-1-mkl@pengutronix.de Cc: Tim Harvey Tested-By: Tim Harvey Reported-by: Gerhard Bertelsmann Signed-off-by: Marc Kleine-Budde Signed-off-by: Sasha Levin --- drivers/net/can/spi/mcp251x.c | 24 ++++++++++++++++++------ 1 file changed, 18 insertions(+), 6 deletions(-) diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c index 22d814ae4edc..42c3046fa304 100644 --- a/drivers/net/can/spi/mcp251x.c +++ b/drivers/net/can/spi/mcp251x.c @@ -314,6 +314,18 @@ static int mcp251x_spi_trans(struct spi_device *spi, int len) return ret; } +static int mcp251x_spi_write(struct spi_device *spi, int len) +{ + struct mcp251x_priv *priv = spi_get_drvdata(spi); + int ret; + + ret = spi_write(spi, priv->spi_tx_buf, len); + if (ret) + dev_err(&spi->dev, "spi write failed: ret = %d\n", ret); + + return ret; +} + static u8 mcp251x_read_reg(struct spi_device *spi, u8 reg) { struct mcp251x_priv *priv = spi_get_drvdata(spi); @@ -361,7 +373,7 @@ static void mcp251x_write_reg(struct spi_device *spi, u8 reg, u8 val) priv->spi_tx_buf[1] = reg; priv->spi_tx_buf[2] = val; - mcp251x_spi_trans(spi, 3); + mcp251x_spi_write(spi, 3); } static void mcp251x_write_2regs(struct spi_device *spi, u8 reg, u8 v1, u8 v2) @@ -373,7 +385,7 @@ static void mcp251x_write_2regs(struct spi_device *spi, u8 reg, u8 v1, u8 v2) priv->spi_tx_buf[2] = v1; priv->spi_tx_buf[3] = v2; - mcp251x_spi_trans(spi, 4); + mcp251x_spi_write(spi, 4); } static void mcp251x_write_bits(struct spi_device *spi, u8 reg, @@ -386,7 +398,7 @@ static void mcp251x_write_bits(struct spi_device *spi, u8 reg, priv->spi_tx_buf[2] = mask; priv->spi_tx_buf[3] = val; - mcp251x_spi_trans(spi, 4); + mcp251x_spi_write(spi, 4); } static u8 mcp251x_read_stat(struct spi_device *spi) @@ -618,7 +630,7 @@ static void mcp251x_hw_tx_frame(struct spi_device *spi, u8 *buf, buf[i]); } else { memcpy(priv->spi_tx_buf, buf, TXBDAT_OFF + len); - mcp251x_spi_trans(spi, TXBDAT_OFF + len); + mcp251x_spi_write(spi, TXBDAT_OFF + len); } } @@ -650,7 +662,7 @@ static void mcp251x_hw_tx(struct spi_device *spi, struct can_frame *frame, /* use INSTRUCTION_RTS, to avoid "repeated frame problem" */ priv->spi_tx_buf[0] = INSTRUCTION_RTS(1 << tx_buf_idx); - mcp251x_spi_trans(priv->spi, 1); + mcp251x_spi_write(priv->spi, 1); } static void mcp251x_hw_rx_frame(struct spi_device *spi, u8 *buf, @@ -888,7 +900,7 @@ static int mcp251x_hw_reset(struct spi_device *spi) mdelay(MCP251X_OST_DELAY_MS); priv->spi_tx_buf[0] = INSTRUCTION_RESET; - ret = mcp251x_spi_trans(spi, 1); + ret = mcp251x_spi_write(spi, 1); if (ret) return ret; -- 2.30.2