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SubjectRe: [PATCH] pinctrl: st: constify gpio_chip structure
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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@embeddedor.com>
> ---
> 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@st.com>

Thanks
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