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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 67CABC169C4 for ; Sun, 3 Feb 2019 13:55:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 41054218D8 for ; Sun, 3 Feb 2019 13:55:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728679AbfBCNzg (ORCPT ); Sun, 3 Feb 2019 08:55:36 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:54538 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729096AbfBCNyq (ORCPT ); Sun, 3 Feb 2019 08:54:46 -0500 Received: from cable-78.29.236.164.coditel.net ([78.29.236.164] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gqIEO-0004R6-K9; Sun, 03 Feb 2019 13:54:44 +0000 Received: from ben by deadeye with local (Exim 4.92-RC4) (envelope-from ) id 1gqIDX-0000Ax-32; Sun, 03 Feb 2019 14:53:51 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Christophe Leroy" , "Linus Walleij" Date: Sun, 03 Feb 2019 14:45:08 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 303/305] gpio: max7301: fix driver for use with CONFIG_VMAP_STACK In-Reply-To: X-SA-Exim-Connect-IP: 78.29.236.164 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.63-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Christophe Leroy commit abf221d2f51b8ce7b9959a8953f880a8b0a1400d upstream. spi_read() and spi_write() require DMA-safe memory. When CONFIG_VMAP_STACK is selected, those functions cannot be used with buffers on stack. This patch replaces calls to spi_read() and spi_write() by spi_write_then_read() which doesn't require DMA-safe buffers. Fixes: 0c36ec314735 ("gpio: gpio driver for max7301 SPI GPIO expander") Signed-off-by: Christophe Leroy Signed-off-by: Linus Walleij Signed-off-by: Ben Hutchings --- drivers/gpio/gpio-max7301.c | 12 +++--------- 1 file changed, 3 insertions(+), 9 deletions(-) --- a/drivers/gpio/gpio-max7301.c +++ b/drivers/gpio/gpio-max7301.c @@ -25,7 +25,7 @@ static int max7301_spi_write(struct devi struct spi_device *spi = to_spi_device(dev); u16 word = ((reg & 0x7F) << 8) | (val & 0xFF); - return spi_write(spi, (const u8 *)&word, sizeof(word)); + return spi_write_then_read(spi, &word, sizeof(word), NULL, 0); } /* A read from the MAX7301 means two transfers; here, one message each */ @@ -37,14 +37,8 @@ static int max7301_spi_read(struct devic struct spi_device *spi = to_spi_device(dev); word = 0x8000 | (reg << 8); - ret = spi_write(spi, (const u8 *)&word, sizeof(word)); - if (ret) - return ret; - /* - * This relies on the fact, that a transfer with NULL tx_buf shifts out - * zero bytes (=NOOP for MAX7301) - */ - ret = spi_read(spi, (u8 *)&word, sizeof(word)); + ret = spi_write_then_read(spi, &word, sizeof(word), &word, + sizeof(word)); if (ret) return ret; return word & 0xff;