From 2dd151ab2792cd27a2268a6e4f3248193beed504 Mon Sep 17 00:00:00 2001 From: Alexander Shishkin Date: Tue, 11 May 2010 11:35:14 -0700 Subject: [PATCH] omap: i2c: make errata 1.153 workaround a separate function This is to avoid insanely long lines and levels of indentation. Signed-off-by: Alexander Shishkin Cc: Nishant Menon Signed-off-by: Tony Lindgren Signed-off-by: Ben Dooks --- drivers/i2c/busses/i2c-omap.c | 43 +++++++++++++++++++---------------- 1 file changed, 24 insertions(+), 19 deletions(-) diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c index 42c0b9108c7f..ef73483efb84 100644 --- a/drivers/i2c/busses/i2c-omap.c +++ b/drivers/i2c/busses/i2c-omap.c @@ -756,6 +756,27 @@ 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) { @@ -885,25 +906,9 @@ 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); } -- 2.20.1