From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from zmta01.irigo.dk (zmta01.cabocomm.dk [193.200.44.52]) by ozlabs.org (Postfix) with ESMTP id CE254DDFE2 for ; Thu, 14 May 2009 18:20:15 +1000 (EST) Message-ID: <4A0BD1DB.4090305@doredevelopment.dk> Date: Thu, 14 May 2009 10:10:03 +0200 From: Esben Haabendal MIME-Version: 1.0 To: linux-i2c@vger.kernel.org Subject: [PATCH] i2c-mpc: generate START condition after STOP caused by read i2c_msg Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This fixes MAL (arbitration lost) bug caused by illegal use of RSTA (repeated START) after STOP condition generated after last byte of reads. Signed-off-by: Esben Haabendal --- drivers/i2c/busses/i2c-mpc.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/i2c/busses/i2c-mpc.c b/drivers/i2c/busses/i2c-mpc.c index 4af5c09..9fe05d9 100644 --- a/drivers/i2c/busses/i2c-mpc.c +++ b/drivers/i2c/busses/i2c-mpc.c @@ -456,17 +456,22 @@ static int mpc_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num) } for (i = 0; ret >= 0 && i < num; i++) { + int restart = i; pmsg = &msgs[i]; dev_dbg(i2c->dev, "Doing %s %d bytes to 0x%02x - %d of %d messages\n", pmsg->flags & I2C_M_RD ? "read" : "write", pmsg->len, pmsg->addr, i + 1, num); + if (i > 0 && ((pmsg-1)->flags & I2C_M_RD)) + restart = 0; if (pmsg->flags & I2C_M_RD) ret = - mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); + mpc_read(i2c, pmsg->addr, pmsg->buf, pmsg->len, + restart); else ret = - mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, i); + mpc_write(i2c, pmsg->addr, pmsg->buf, pmsg->len, + restart); } mpc_i2c_stop(i2c); return (ret < 0) ? ret : num; -- 1.6.0.4