From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Re: [PATCH v2 1/2] omap i2c: make errata 1.153 workaround a separate function Date: Mon, 28 Dec 2009 16:13:56 -0800 Message-ID: <20091229001356.GU3512@atomide.com> References: <1261394999-20857-1-git-send-email-virtuoso@slind.org> <1261394999-20857-2-git-send-email-virtuoso@slind.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: <1261394999-20857-2-git-send-email-virtuoso-0lOfPCoBze7YtjvyW6yDsg@public.gmane.org> Sender: linux-i2c-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Alexander Shishkin Cc: ben-linux-elnMNo+KYs3YtjvyW6yDsg@public.gmane.org, nm-l0cyMroinI0@public.gmane.org, linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-i2c@vger.kernel.org * Alexander Shishkin [091221 03:29]: > This is to avoid insanely long lines and levels of indentation. > > Signed-off-by: Alexander Shishkin > CC: linux-i2c-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > CC: linux-omap-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > CC: nm-l0cyMroinI0@public.gmane.org Nice, this driver sure could use some clean-up. Acked-by: Tony Lindgren > --- > drivers/i2c/busses/i2c-omap.c | 43 ++++++++++++++++++++++------------------ > 1 files changed, 24 insertions(+), 19 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c > index 75bf3ad..2d146ac 100644 > --- a/drivers/i2c/busses/i2c-omap.c > +++ b/drivers/i2c/busses/i2c-omap.c > @@ -671,6 +671,27 @@ omap_i2c_rev1_isr(int this_irq, void *dev_id) > #define omap_i2c_rev1_isr NULL > #endif > > +/* > + * OMAP3430 Errata 1.153: When an XRDY/XDR is hit, wait for XUDF before writing > + * 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_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err) > +{ > + while (!(*stat & OMAP_I2C_STAT_XUDF)) { > + if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { > + omap_i2c_ack_stat(dev, *stat & (OMAP_I2C_STAT_XRDY | > + OMAP_I2C_STAT_XDR)); > + *err |= OMAP_I2C_STAT_XUDF; > + return -ETIMEDOUT; > + } > + cpu_relax(); > + *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); > + } > + > + return 0; > +} > + > static irqreturn_t > omap_i2c_isr(int this_irq, void *dev_id) > { > @@ -794,25 +815,9 @@ complete: > break; > } > > - /* > - * OMAP3430 Errata 1.153: When an XRDY/XDR > - * is hit, wait for XUDF before writing data > - * to DATA_REG. Otherwise some data bytes can > - * be lost while transferring them from the > - * memory to the I2C interface. > - */ > - > - if (dev->rev <= OMAP_I2C_REV_ON_3430) { > - while (!(stat & OMAP_I2C_STAT_XUDF)) { > - if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) { > - omap_i2c_ack_stat(dev, stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)); > - err |= OMAP_I2C_STAT_XUDF; > - goto complete; > - } > - cpu_relax(); > - stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG); > - } > - } > + if ((dev->rev <= OMAP_I2C_REV_ON_3430) && > + errata_omap3_1p153(dev, &stat, &err)) > + goto complete; > > omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w); > } > -- > 1.6.3.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-i2c" in > the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org > More majordomo info at http://vger.kernel.org/majordomo-info.html