diff options
Diffstat (limited to 'recipes/linux/linux-omap1-2.6.19-omap1/i2c-fix.patch')
| -rw-r--r-- | recipes/linux/linux-omap1-2.6.19-omap1/i2c-fix.patch | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/recipes/linux/linux-omap1-2.6.19-omap1/i2c-fix.patch b/recipes/linux/linux-omap1-2.6.19-omap1/i2c-fix.patch new file mode 100644 index 0000000000..3b35ce23a2 --- /dev/null +++ b/recipes/linux/linux-omap1-2.6.19-omap1/i2c-fix.patch @@ -0,0 +1,56 @@ +Hack to add I2C zero length transfers and SMBus quick mode +necessary for AIC23 sound again. + +Signed-off-by: Dirk Behme <dirk.behme_at_gmail.com> + + +-------------- next part -------------- +Index: linux-osk/drivers/i2c/busses/i2c-omap.c +=================================================================== +--- linux-osk.orig/drivers/i2c/busses/i2c-omap.c ++++ linux-osk/drivers/i2c/busses/i2c-omap.c +@@ -285,20 +285,29 @@ static int omap_i2c_xfer_msg(struct i2c_ + struct i2c_msg *msg, int stop) + { + struct omap_i2c_dev *dev = i2c_get_adapdata(adap); ++ u8 zero_byte = 0; + int r; + u16 w; + + dev_dbg(dev->dev, "addr: 0x%04x, len: %d, flags: 0x%x, stop: %d\n", + msg->addr, msg->len, msg->flags, stop); + +- if (msg->len == 0) +- return -EINVAL; +- + omap_i2c_write_reg(dev, OMAP_I2C_SA_REG, msg->addr); + +- /* REVISIT: Could the STB bit of I2C_CON be used with probing? */ +- dev->buf = msg->buf; +- dev->buf_len = msg->len; ++ /* Sigh, seems we can't do zero length transactions. Thus, we ++ * can't probe for devices w/o actually sending/receiving at least ++ * a single byte. So we'll set count to 1 for the zero length ++ * transaction case and hope we don't cause grief for some ++ * arbitrary device due to random byte write/read during ++ * probes. ++ */ ++ if (msg->len == 0) { ++ dev->buf = &zero_byte; ++ dev->buf_len = 1; ++ } else { ++ dev->buf = msg->buf; ++ dev->buf_len = msg->len; ++ } + + omap_i2c_write_reg(dev, OMAP_I2C_CNT_REG, dev->buf_len); + +@@ -383,7 +392,7 @@ out: + static u32 + omap_i2c_func(struct i2c_adapter *adap) + { +- return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK); ++ return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL; + } + + static inline void |