"Sudhakar Rajashekhara" <[email protected]> writes: > Kevin, > > On Wed, Jan 27, 2010 at 20:20:08, Kevin Hilman wrote: >> "Sudhakar Rajashekhara" <[email protected]> writes: >> >> > Hi, >> > >> > On Wed, Jan 27, 2010 at 05:11:28, Kevin Hilman wrote: >> >> From: Dirk Behme <[email protected]> >> >> >> >> This fixes Oops at kernel startup while "scanning" for TLV320AIC23IDx >> >> addresses. >> >> >> >> Signed-off-by: Alexander Vasiliev <[email protected]> >> >> Signed-off-by: Brad Griffis <[email protected]> >> >> Signed-off-by: Dirk Behme <[email protected]> >> >> Acked-by: Kevin Hilman <[email protected]> >> >> --- >> >> drivers/i2c/busses/i2c-davinci.c | 29 +++++++++++++++++++++++++---- >> >> 1 files changed, 25 insertions(+), 4 deletions(-) >> >> >> >> diff --git a/drivers/i2c/busses/i2c-davinci.c >> >> b/drivers/i2c/busses/i2c-davinci.c >> >> index c89687a..444a9f2 100644 >> >> --- a/drivers/i2c/busses/i2c-davinci.c >> >> +++ b/drivers/i2c/busses/i2c-davinci.c >> > >> > [...] >> > >> >> @@ -290,6 +293,16 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, >> >> struct i2c_msg *msg, int stop) >> >> davinci_i2c_write_reg(dev, DAVINCI_I2C_IMR_REG, w); >> >> >> >> dev->terminate = 0; >> >> + >> >> + /* First byte should be set here, not after interrupt, >> >> + * because transmit-data-ready interrupt can come before >> >> + * NACK-interrupt during sending of previous message and >> >> + * ICDXR may have wrong data */ >> >> + if ((!(msg->flags & I2C_M_RD)) && dev->buf_len) { >> >> + davinci_i2c_write_reg(dev, DAVINCI_I2C_DXR_REG, *dev->buf++); >> >> + dev->buf_len--; >> >> + } >> >> + >> > >> > I found an issue on DA850 while using this patch. >> >> ok, I'll drop this one for 2.6.34 until we figure this out. >> >> > I think the above code should come after the >> > below lines because an I2C transaction is being carried out before >> > configuring the I2C mode >> > register (which has bits to configure Master, Start condition etc), which >> > causes undefined >> > behavior. >> >> hmm, are you seeing this behavior on davinci git too? This is the same >> patch that has been in davinci git for some time? >> > > The following patch fixes the issue I reported. I have tested it extensively > on DA850/OMAP-L138. > You can roll-in these changes into the current patch.
Thanks, I rolled it into the original, and updated the 'davinci-upstream-submitted' branch. Kevin > Signed-off-by: Sudhakar Rajashekhara <[email protected]> > --- > drivers/i2c/busses/i2c-davinci.c | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-davinci.c > b/drivers/i2c/busses/i2c-davinci.c > index 35f9daa..8526bce 100644 > --- a/drivers/i2c/busses/i2c-davinci.c > +++ b/drivers/i2c/busses/i2c-davinci.c > @@ -308,6 +308,9 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct > i2c_msg *msg, int stop) > > dev->terminate = 0; > > + /* write the data into mode register */ > + davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); > + > /* First byte should be set here, not after interrupt, > * because transmit-data-ready interrupt can come before > * NACK-interrupt during sending of previous message and > @@ -317,9 +320,6 @@ i2c_davinci_xfer_msg(struct i2c_adapter *adap, struct > i2c_msg *msg, int stop) > dev->buf_len--; > } > > - /* write the data into mode register */ > - davinci_i2c_write_reg(dev, DAVINCI_I2C_MDR_REG, flag); > - > r = wait_for_completion_interruptible_timeout(&dev->cmd_complete, > dev->adapter.timeout); > if (r == 0) { > -- > > Regards, > Sudhakar -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
