From: Marek Vasut <marex@denx.de>
To: Andreas Werner <wernerandy@gmx.de>
Cc: wsa@the-dreams.de, jacmet@sunsite.dk, baohua.song@csr.com,
linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] I2C: busses: Do not print error message in syslog if no ACK received
Date: Wed, 13 Nov 2013 20:24:06 +0100 [thread overview]
Message-ID: <201311132024.06853.marex@denx.de> (raw)
In-Reply-To: <20131113182415.GA1458@thinkpad.fritz.box>
Dear Andreas Werner,
> On Tue, Nov 12, 2013 at 07:33:40PM +0100, Marek Vasut wrote:
> > Dear Andreas Werner,
> >
> > > On Tue, Nov 12, 2013 at 07:00:59PM +0100, Marek Vasut wrote:
> > > > Dear Andreas Werner,
> > > >
> > > > > Using the i2c-eg20t driver and call i2cdetect or probe on the bus,
> > > > > the driver will print a lot of error messages if there was no ACK
> > > > > received.
> > > > >
> > > > > i2cdetect normally print a table with all the available devices. If
> > > > > there is no device on the address, the table will be empty.
> > > > > Currently with the i2c-eg20t driver, the table is not visible
> > > > > because the error messages destroy the table.
> > > > >
> > > > > Error message: pch_i2c_getack return -71
> > > > >
> > > > > This patch prevent the driver to print the messages to syslog if
> > > > > debug is not set.
> > > > >
> > > > > Tested on Intel Atom E6xx and Eg20t Chipset.
> > > > >
> > > > > Signed-off-by: Andreas Werner <wernerandy@gmx.de>
> > > > > ---
> > > > >
> > > > > drivers/i2c/busses/i2c-eg20t.c | 2 +-
> > > > > 1 file changed, 1 insertion(+), 1 deletion(-)
> > > > >
> > > > > diff --git a/drivers/i2c/busses/i2c-eg20t.c
> > > > > b/drivers/i2c/busses/i2c-eg20t.c index 0f37529..b10c651 100644
> > > > > --- a/drivers/i2c/busses/i2c-eg20t.c
> > > > > +++ b/drivers/i2c/busses/i2c-eg20t.c
> > > > > @@ -322,7 +322,7 @@ static s32 pch_i2c_getack(struct
> > > > > i2c_algo_pch_data *adap) reg_val = ioread32(p + PCH_I2CSR) &
> > > > > PCH_GETACK;
> > > > >
> > > > > if (reg_val != 0) {
> > > > >
> > > > > - pch_err(adap, "return%d\n", -EPROTO);
> > > > > + pch_dbg(adap, "return%d\n", -EPROTO);
> > > > >
> > > > > return -EPROTO;
> > > > >
> > > > > }
> > > >
> > > > I'd just kill the pch_err() line altogether:
> > > But why? I think there a few pch_err message which are interesting to
> > >
> > > have in syslog, without building the dbg driver.
> >
> > See below for explanation why this one particular pch_err() line can go.
> > Sorry if I was not clear enough, I meant only this one particular
> > pch_err() line, NOT all of them.
> >
> > > > if (reg_val)
> > > >
> > > > return -EPROTO;
> > > >
> > > > That is because if you look at the only caller of this function,
> > > > which is pch_i2c_wait_for_check_xfer(), you will see that at the
> > > > only place where pch_i2c_getack() is called there is already
> > > > pch_dbg():
> > > >
> > > > 369 if (pch_i2c_getack(adap)) {
> > > > 370 pch_dbg(adap, "Receive NACK for slave address"
> > > > 371 "setting\n");
> > > > 372 return -EIO;
> > > > 373 }
>
> Sorry i misunderstood that. You are absolutly right, thats the best
> solution for that. Remove the pch_err at getack so that only the pch_dbg
> get printed where getack is called. This should be enough information.
No problem ;-)
next prev parent reply other threads:[~2013-11-14 2:33 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-11-12 17:45 [PATCH] I2C: busses: Do not print error message in syslog if no ACK received Andreas Werner
2013-11-12 18:00 ` Marek Vasut
2013-11-12 18:23 ` Andreas Werner
2013-11-12 18:33 ` Marek Vasut
2013-11-13 18:24 ` Andreas Werner
2013-11-13 19:24 ` Marek Vasut [this message]
2013-11-14 13:39 ` Joe Perches
2013-11-14 18:26 ` Andreas Werner
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