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authorAlexander Shishkin <virtuoso@slind.org>2010-05-11 20:35:14 +0200
committerBen Dooks <ben-linux@fluff.org>2010-05-20 01:18:59 +0200
commit2dd151ab2792cd27a2268a6e4f3248193beed504 (patch)
treee12ad3c787db9770db5850e163ef1875127bb1ce /drivers/i2c
parenti2c-omap: add mpu wake up latency constraint in i2c (diff)
downloadlinux-2dd151ab2792cd27a2268a6e4f3248193beed504.tar.xz
linux-2dd151ab2792cd27a2268a6e4f3248193beed504.zip
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 <virtuoso@slind.org> Cc: Nishant Menon <nm@ti.com> Signed-off-by: Tony Lindgren <tony@atomide.com> Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Diffstat (limited to 'drivers/i2c')
-rw-r--r--drivers/i2c/busses/i2c-omap.c43
1 files 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);
}