On Thu, 27 Feb 2020, afzal mohammed wrote:
On Thu, Feb 27, 2020 at 09:32:46AM +0100, Geert Uytterhoeven wrote:
On Thu, Feb 27, 2020 at 9:18 AM afzal mohammed <afzal.mohd.ma@xxxxxxxxx> wrote:
Since most of the existing setup_irq() didn't even check & handle
error return, my first thought was just s/setup_irq/request_irq, it
was easier from scripting pointing of view. i felt uncomfortable
doing nothing in case of error. Also noted that request_irq()
definition has a "__much_check", so decided to add it.
Most (all?) of the code calling setup_irq() is very old, and most of
the calls happen very early, so any such failures are hard failures
that prevent the system from booting at all. Hence printing a message
may be futile, as it may happen before the console has been
initialized (modulo early-printk).
The main reason to at least acknowledge the return value was due to
__much_check in request_irq() definition, though w/ the compiler that i
used, there were no warnings, i feared that it might warn w/ some other
compilers & in some cases (may be W=[1-3] ?).
This isn't new code, so I'd assume it's been "checked" in the sense of
"reviewed and tested".
So the lack of an error message could be taken to mean that there's no
need for an error message.
If you want to stop the compiler complaining about an unchecked return
value, assuming that it does so, please consider using
if (request_irq(...))
pr_debug(...);
That way there is no penalty paid for adding error messages that the
original author apparently did not want.
