From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755291AbaHUViq (ORCPT ); Thu, 21 Aug 2014 17:38:46 -0400 Received: from regular1.263xmail.com ([211.150.99.130]:60027 "EHLO regular1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755242AbaHUVin (ORCPT ); Thu, 21 Aug 2014 17:38:43 -0400 X-Greylist: delayed 13646 seconds by postgrey-1.27 at vger.kernel.org; Thu, 21 Aug 2014 17:38:43 EDT 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: <13879d8b5b4835dd93934f902291459e> X-ATTACHMENT-NUM: 0 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 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 v2] i2c: rk3x: fix bug that cause transfer fails in maste receive mode Date: Fri, 22 Aug 2014 05:38:27 +0800 Message-Id: <1408657107-8715-1-git-send-email-addy.ke@rock-chips.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <0001-i2c-rk3x-fix-bug-that-cause-transfer-fails-in-master.patch> References: <0001-i2c-rk3x-fix-bug-that-cause-transfer-fails-in-master.patch> 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. Acked-by: Max Schwarz Signed-off-by: Addy Ke --- Changes in v2: - Use cleaner syntax as suggested by Sergei. - Update commit message as suggested by Wolfram. drivers/i2c/busses/i2c-rk3x.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/drivers/i2c/busses/i2c-rk3x.c b/drivers/i2c/busses/i2c-rk3x.c index 69e1185..806724a 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 (unlikely(len > 32)) + len = 32; + /* read the data from receive buffer */ for (i = 0; i < len; ++i) { if (i % 4 == 0) -- 1.8.3.2