From patchwork Tue Sep 11 09:42:02 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shubhrajyoti Datta X-Patchwork-Id: 1436631 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 A97033FC33 for ; Tue, 11 Sep 2012 09:44:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758397Ab2IKJnY (ORCPT ); Tue, 11 Sep 2012 05:43:24 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:47520 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757946Ab2IKJnV (ORCPT ); Tue, 11 Sep 2012 05:43:21 -0400 Received: from dbdp20.itg.ti.com ([172.24.170.38]) by comal.ext.ti.com (8.13.7/8.13.7) with ESMTP id q8B9ggWJ008264; Tue, 11 Sep 2012 04:42:43 -0500 Received: from DBDE71.ent.ti.com (localhost [127.0.0.1]) by dbdp20.itg.ti.com (8.13.8/8.13.8) with ESMTP id q8B9gg7r009097; Tue, 11 Sep 2012 15:12:42 +0530 (IST) Received: from dbdp32.itg.ti.com (172.24.170.251) by DBDE71.ent.ti.com (172.24.170.149) with Microsoft SMTP Server id 14.1.323.3; Tue, 11 Sep 2012 15:12:41 +0530 Received: from ula0393217.india.ti.com (smtpvbd.itg.ti.com [172.24.170.250]) by dbdp32.itg.ti.com (8.13.8/8.13.8) with ESMTP id q8B9gKDV010282; Tue, 11 Sep 2012 15:12:41 +0530 From: Shubhrajyoti D To: CC: , , , , , Felipe Balbi , Shubhrajyoti D Subject: [PATCHv7 07/23] i2c: omap: improve i462 errata handling Date: Tue, 11 Sep 2012 15:12:02 +0530 Message-ID: <1347356538-23835-8-git-send-email-shubhrajyoti@ti.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1347356538-23835-1-git-send-email-shubhrajyoti@ti.com> References: <1347356538-23835-1-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); }