Re: [PATCH] pinctrl: st: constify gpio_chip structure

[Gustavo A. R. Silva]

Hi Patrice,

Quoting Patrice CHOTARD <patrice.chotard@xxxxxx>:

> Hi Gustavo
>
> On 07/11/2017 08:15 PM, Gustavo A. R. Silva wrote:
> > This structure is only used to copy into other structure, so declare
> > it as const.
> >
> > This issue was detected using Coccinelle and the following semantic patch:
> >
> > @r disable optional_qualifier@
> > identifier i;
> > position p;
> > @@
> > static struct gpio_chip i@p = { ... };
> >
> > @ok@
> > identifier r.i;
> > expression e;
> > position p;
> > @@
> > e = i@p;
> >
> > @bad@
> > position p != {r.p,ok.p};
> > identifier r.i;
> > struct gpio_chip e;
> > @@
> > e@i@p
> >
> > @depends on !bad disable optional_qualifier@
> > identifier r.i;
> > @@
> > static
> > +const
> >   struct gpio_chip i = { ... };
> >
> > In the following log you can see a significant difference in the code size
> > and data segment, hence in the dec segment. This log is the output
> > of the size command, before and after the code change:
> >
> > before:
> >     text    data     bss     dec     hex filename
> >    21671    3632     128   25431    6357 drivers/pinctrl/pinctrl-st.o
> >
> > after:
> >     text    data     bss     dec     hex filename
> >    21366    3576     128   25070    61ee drivers/pinctrl/pinctrl-st.o
> >
> > Signed-off-by: Gustavo A. R. Silva <garsilva@xxxxxxxxxxxxxx>
> > ---
> >   drivers/pinctrl/pinctrl-st.c | 2 +-
> >   1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/pinctrl/pinctrl-st.c b/drivers/pinctrl/pinctrl-st.c
> > index 3ae8066..5d4789d 100644
> > --- a/drivers/pinctrl/pinctrl-st.c
> > +++ b/drivers/pinctrl/pinctrl-st.c
> > @@ -1442,7 +1442,7 @@ static void st_gpio_irqmux_handler(struct  
> > irq_desc *desc)
> >   	chained_irq_exit(chip, desc);
> >   }
> >
> > -static struct gpio_chip st_gpio_template = {
> > +static const struct gpio_chip st_gpio_template = {
> >   	.request		= gpiochip_generic_request,
> >   	.free			= gpiochip_generic_free,
> >   	.get			= st_gpio_get,
>
> Acked-by: Patrice Chotard <patrice.chotard@xxxxxx>
>
> Thanks

Glad to help. :)

Thanks
--
Gustavo A. R. Silva