From patchwork Thu Jul 19 14:37:57 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shubhrajyoti Datta X-Patchwork-Id: 1217421 Return-Path: X-Original-To: patchwork-linux-omap@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id F3A3CDF24C for ; Thu, 19 Jul 2012 14:43:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752615Ab2GSOmx (ORCPT ); Thu, 19 Jul 2012 10:42:53 -0400 Received: from comal.ext.ti.com ([198.47.26.152]:35971 "EHLO comal.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752527Ab2GSOmv (ORCPT ); Thu, 19 Jul 2012 10:42:51 -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 q6JEcR8p031797; Thu, 19 Jul 2012 09:38:28 -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 q6JEcPIf003813; Thu, 19 Jul 2012 20:08:27 +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; Thu, 19 Jul 2012 20:08:26 +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 q6JEcLWO030469; Thu, 19 Jul 2012 20:08:25 +0530 From: Shubhrajyoti D To: CC: , , , , , Felipe Balbi , Shubhrajyoti D Subject: [PATCHv5 07/18] i2c: omap: improve i462 errata handling Date: Thu, 19 Jul 2012 20:07:57 +0530 Message-ID: <1342708688-2342-8-git-send-email-shubhrajyoti@ti.com> X-Mailer: git-send-email 1.7.5.4 In-Reply-To: <1342708688-2342-1-git-send-email-shubhrajyoti@ti.com> References: <1342708688-2342-1-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 [Avoid flagging the XUDF] 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 5f6d9c5..6f98812 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -722,27 +722,30 @@ 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; } @@ -900,9 +903,16 @@ 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); } @@ -940,9 +950,16 @@ 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); }