From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932855AbaHVSBs (ORCPT ); Fri, 22 Aug 2014 14:01:48 -0400 Received: from regular1.263xmail.com ([211.150.99.135]:41948 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932410AbaHVSBq (ORCPT ); Fri, 22 Aug 2014 14:01:46 -0400 X-263anti-spam: KSV:0; X-MAIL-GRAY: 0 X-MAIL-DELIVERY: 1 X-ABS-CHECKED: 4 X-KSVirus-check: 0 X-RL-SENDER: addy.ke@rock-chips.com X-FST-TO: wsa@the-dreams.de X-SENDER-IP: 127.0.0.1 X-LOGIN-NAME: addy.ke@rock-chips.com X-UNIQUE-TAG: X-DNS-TYPE: 1 From: Addy Ke To: wsa@the-dreams.de, max.schwarz@online.de, heiko@sntech.de, olof@lixom.net, dianders@chromium.org, dmitry.torokhov@gmail.com Cc: sergei.shtylyov@cogentembedded.com, linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org, cf@rock-chips.com, xjq@rock-chips.com, huangtao@rock-chips.com, zyw@rock-chips.com, yzq@rock-chips.com, hj@rock-chips.com, kever.yang@rock-chips.com, hl@rock-chips.com, caesar.wang@rock-chips.com, zhengsq@rock-chips.com, Addy Ke Subject: [PATCH v4] i2c: rk3x: fix bug that cause transfer fails in master receive mode Date: Sat, 23 Aug 2014 02:00:52 +0800 Message-Id: <1408730452-3552-1-git-send-email-addy.ke@rock-chips.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1408669991-9703-1-git-send-email-addy.ke@rock-chips.com> References: <1408669991-9703-1-git-send-email-addy.ke@rock-chips.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org In rk3x SOC, the I2C controller can receive/transmit up to 32 bytes data in one chunk, so the size of data to be write/read to/from TXDATAx/RXDATAx must be less than or equal 32 bytes at a time. Tested on rk3288-pinky board, elan receive 158 bytes data. Suggested-by: Dmitry Torokhov Signed-off-by: Addy Ke Acked-by: Max Schwarz --- Changes in v2: - Use cleaner syntax as suggested by Sergei. - Update commit message as suggested by Wolfram. Changes in v3: - fix typo: maste --> master and double spaces after 'len' drivers/i2c/busses/i2c-rk3x.c | 4 ++++ Changes in v4: - remove unlikely() annotations, suggested by Dmitry Torokhov diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c index b8b2b89..31de730 100644 --- a/drivers/i2c/busses/i2c-rk3x.c +++ b/drivers/i2c/busses/i2c-rk3x.c @@ -323,6 +323,10 @@ static void rk3x_i2c_handle_read(struct rk3x_i2c *i2c, unsigned int ipd) /* ack interrupt */ i2c_writel(i2c, REG_INT_MBRF, REG_IPD); + /* Can only handle a maximum of 32 bytes at a time */ + if (len > 32) + len = 32; + /* read the data from receive buffer */ for (i = 0; i < len; ++i) { if (i % 4 == 0) -- 1.8.3.2