Re: [PATCH v2 5/5] rtc: add mxc driver for i.MX53 SRTC

[Sascha Hauer]

On Wed, Dec 06, 2017 at 10:17:06AM +0000, Patrick Brünn wrote:
> >From: Sascha Hauer [mailto:s.hauer@xxxxxxxxxxxxxx]
> >Sent: Mittwoch, 6. Dezember 2017 09:36
> >On Tue, Dec 05, 2017 at 03:06:46PM +0100, linux-kernel-dev@xxxxxxxxxxxx
> >wrote:
> >> +static int mxc_rtc_wait_for_flag(void *__iomem ioaddr, int flag)
> >> +{
> >> +    unsigned int timeout = REG_READ_TIMEOUT;
> >> +
> >> +    while (!(readl(ioaddr) & flag)) {
> >> +            if (!--timeout) {
> >> +                    pr_err("Wait timeout for 0x%x@%p!\n", flag, ioaddr);
> >
> >Please use dev_* functions for printing. In this case the message should
> >probably be printed from the caller.
> Do you have a link at hand about dev_* vs. pr_*? I just choose pr_err here,
> because I would have to change the functions signature to get a device.
> However, I will drop the message and move it to the caller.

No, I don't have a link. However, a message printed with pr_err comes
with absolutely no context, so without grepping the source you do not
get a clue which device has a problem. You could add more context
using some prefix either to each message or by using

#define pr_fmt(fmt) "mydriver: " fmt

but then you still not know which instance the message throws. Using
dev_* just does the right thing without much thinking.

Sascha

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