Re: [PATCH v2 2/4] i2c: designware: Ensure tx_buf_len is nonzero for SMBus block reads
From: Andy Shevchenko
Date: Thu Sep 17 2020 - 15:56:19 EST
On Thu, Sep 17, 2020 at 04:44:18PM +0300, Jarkko Nikula wrote:
> On 9/17/20 8:22 AM, Sultan Alsawaf wrote:
> > From: Sultan Alsawaf <sultan@xxxxxxxxxxxxxxx>
> > The point of adding a byte to len in i2c_dw_recv_len() is to make sure
> > that tx_buf_len is nonzero, so that i2c_dw_xfer_msg() can let the i2c
> > controller know that the i2c transaction can end. Otherwise, the i2c
> > controller will think that the transaction can never end for block
> > reads, which results in the stop-detection bit never being set and thus
> > the transaction timing out.
> > Adding a byte to len is not a reliable way to do this though; sometimes
> > it lets tx_buf_len become zero, which results in the scenario described
> > above. Therefore, just directly ensure tx_buf_len cannot be zero to fix
> > the issue.
> > Fixes: c3ae106050b9 ("i2c: designware: Implement support for SMBus block read and write")
> > Signed-off-by: Sultan Alsawaf <sultan@xxxxxxxxxxxxxxx>
> > ---
> > drivers/i2c/busses/i2c-designware-master.c | 5 +++--
> > 1 file changed, 3 insertions(+), 2 deletions(-)
> Were other patches in series dropped somewhere? I received only this.
@linux.intel.com has some issues in delivery (accepting) messages. You may
download thru lore.kernel.org entire series and reply.
With Best Regards,