From patchwork Wed Sep 12 10:58:01 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shubhrajyoti Datta X-Patchwork-Id: 1442391 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork1.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork1.kernel.org (Postfix) with ESMTP id 246354025E for ; Wed, 12 Sep 2012 10:59:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757550Ab2ILK7H (ORCPT ); Wed, 12 Sep 2012 06:59:07 -0400 Received: from devils.ext.ti.com ([198.47.26.153]:57173 "EHLO devils.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757518Ab2ILK7A (ORCPT ); Wed, 12 Sep 2012 06:59:00 -0400 Received: from dbdp20.itg.ti.com ([172.24.170.38]) by devils.ext.ti.com (8.13.7/8.13.7) with ESMTP id q8CAwRAs006555; Wed, 12 Sep 2012 05:58:28 -0500 Received: from DBDE70.ent.ti.com (localhost [127.0.0.1]) by dbdp20.itg.ti.com (8.13.8/8.13.8) with ESMTP id q8CAwNX5018579; Wed, 12 Sep 2012 16:28:27 +0530 (IST) Received: from dbdp33.itg.ti.com (172.24.170.252) by dbde70.ent.ti.com (172.24.170.148) with Microsoft SMTP Server id 14.1.323.3; Wed, 12 Sep 2012 16:28:24 +0530 Received: from ula0393217.india.ti.com (smtpvbd.itg.ti.com [172.24.170.250]) by dbdp33.itg.ti.com (8.13.8/8.13.8) with ESMTP id q8CAwJZE009194; Wed, 12 Sep 2012 16:28:24 +0530 From: Shubhrajyoti D To: CC: , , , , , Felipe Balbi , Shubhrajyoti D Subject: [PATCHv8 07/22] i2c: omap: improve i462 errata handling Date: Wed, 12 Sep 2012 16:28:01 +0530 Message-ID: <1347447496-16793-8-git-send-email-shubhrajyoti@ti.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1347447496-16793-1-git-send-email-shubhrajyoti@ti.com> References: <1347447496-16793-1-git-send-email-shubhrajyoti@ti.com> MIME-Version: 1.0 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org From: Felipe Balbi Make it not depend on ISR's local variables in order to make it easier to re-factor the transmit data loop. Also since we are waiting for XUDF(Transmitter underflow) just before writing data lets not flag the underflow. This is anyways going to go once we write the data. Signed-off-by: Felipe Balbi Signed-off-by: Shubhrajyoti D --- drivers/i2c/busses/i2c-omap.c | 43 ++++++++++++++++++++++++++++------------ 1 files changed, 30 insertions(+), 13 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 815577b..fb57221 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -725,27 +725,30 @@ omap_i2c_omap1_isr(int this_irq, void *dev_id) * data to DATA_REG. Otherwise some data bytes can be lost while transferring * them from the memory to the I2C interface. */ -static int errata_omap3_i462(struct omap_i2c_dev *dev, u16 *stat, int *err) +static int errata_omap3_i462(struct omap_i2c_dev *dev) { unsigned long timeout = 10000; + u16 stat; - while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) { - if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { + do { + stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); + if (stat & OMAP_I2C_STAT_XUDF) + break; + + if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); - return -ETIMEDOUT; + return -EIO; } cpu_relax(); - *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); - } + } while (--timeout); if (!timeout) { dev_err(dev->dev, "timeout waiting on XUDF bit\n"); return 0; } - *err |= OMAP_I2C_STAT_XUDF; return 0; } @@ -903,9 +906,16 @@ complete: } } - if ((dev->errata & I2C_OMAP_ERRATA_I462) && - errata_omap3_i462(dev, &stat, &err)) - goto complete; + if (dev->errata & I2C_OMAP_ERRATA_I462) { + int ret; + + ret = errata_omap3_i462(dev); + stat = omap_i2c_read_reg(dev, + OMAP_I2C_STAT_REG); + + if (ret < 0) + goto complete; + } omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); } @@ -943,9 +953,16 @@ complete: } } - if ((dev->errata & I2C_OMAP_ERRATA_I462) && - errata_omap3_i462(dev, &stat, &err)) - goto complete; + if (dev->errata & I2C_OMAP_ERRATA_I462) { + int ret; + + ret = errata_omap3_i462(dev); + stat = omap_i2c_read_reg(dev, + OMAP_I2C_STAT_REG); + + if (ret < 0) + goto complete; + } omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); }