Re: [PATCH] iio: sca3000: Remove an erroneous 'get_device()'

[Jonathan Cameron <Jonathan.Cameron@Huawei.com>]

On Wed, 6 May 2020 19:31:38 +0200
Marion & Christophe JAILLET <christophe.jaillet@wanadoo.fr> wrote:

> Le 06/05/2020 à 12:38, Andy Shevchenko a écrit :
> > On Wed, May 6, 2020 at 6:55 AM Christophe JAILLET
> > <christophe.jaillet@wanadoo.fr> wrote:  
> >> This looks really unusual to have a 'get_device()' hidden in a 'dev_err()'
> >> call.
> >> Remove it.
> >>
> >> While at it add a missing \n at the end of the message.
> >>  
> > It should have Fixes tag because it is a quite an issue (get_device()
> > breaks reference counting with all problems we may expect).  
> 
> Agreed and I usually do, but here, I've lost track when this driver has 
> gone out of staging.
> 
> Based on:
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/drivers/iio/accel/sca3000.c
> The issue was already there on 2016/10/23, but when I try to go one step 
> further:
> 
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/staging/iio/accel/sca3000.c?id=2ccf61442ff142d2dde7c47471c2798a4d78b0ad
> ^^^^         ^^^^^^^
> works but if I try to see the log for that:
> https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/drivers/staging/iio/accel/sca3000.c
> ^^^         ^^^^^^^
> is empty.
> 
> Most of the time, when I do it like that it works just fine, but not on 
> this file.

Oddity of the web interface. Edit the url to get a log form a commit

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/drivers/staging/iio/accel/sca3000.c?id=2ccf61442ff142d2dde7c47471c2798a4d78b0ad
                                                                    ^^^
Then for more fun you have to deal with another rename
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/staging/iio/accel/?id=ced5c03d360aeebaac6faa7dd8d6d0a77733ab16

Next bit of log...
https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/log/drivers/staging/iio/accel/sca3000_ring.c?id=ced5c03d360aeebaac6faa7dd8d6d0a77733ab16 

It goes all the way..

https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/drivers/staging/iio/accel/sca3000_core.c?id=574fb258d63658e4564c32c1940068a3bad666a0

Fixes: 574fb258d636 ("Staging: IIO: VTI sca3000 series accelerometer driver (spi)")

Which was in the initial IIO patch set nearly 11 years ago in the merge window for 2.6.32.

What can I say - I was young and just as capable of writing dumb bugs as I am today :)

I'll get this queued up when I'm on the right computer...

Thanks,

Jonathan


> 
> Any other way to navigate in history of moved file would be appreciated.
> 
> CJ
> 
> >  
> >> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> >> ---
> >> This patch is purely speculative.
> >> I've looked a bit arround and see no point for this get_device() but other
> >> eyes are welcomed :)
> >> ---
> >>   drivers/iio/accel/sca3000.c | 2 +-
> >>   1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/drivers/iio/accel/sca3000.c b/drivers/iio/accel/sca3000.c
> >> index 66d768d971e1..6e429072e44a 100644
> >> --- a/drivers/iio/accel/sca3000.c
> >> +++ b/drivers/iio/accel/sca3000.c
> >> @@ -980,7 +980,7 @@ static int sca3000_read_data(struct sca3000_state *st,
> >>          st->tx[0] = SCA3000_READ_REG(reg_address_high);
> >>          ret = spi_sync_transfer(st->us, xfer, ARRAY_SIZE(xfer));
> >>          if (ret) {
> >> -               dev_err(get_device(&st->us->dev), "problem reading register");
> >> +               dev_err(&st->us->dev, "problem reading register\n");
> >>                  return ret;
> >>          }
> >>
> >> --
> >> 2.25.1
> >>  
> >