Re: [PATCH 1/1] i2c: at91: constify at91_twi_pdata
From: Michał Mirosław
Date: Sun Jul 02 2023 - 06:42:41 EST
On Fri, Jun 30, 2023 at 12:38:25AM +0200, Andi Shyti wrote:
> Hi Michal,
>
> [...]
>
> > -static struct at91_twi_pdata *at91_twi_get_driver_data(
> > +static const struct at91_twi_pdata *at91_twi_get_driver_data(
> > struct platform_device *pdev)
> > {
> > if (pdev->dev.of_node) {
> > @@ -189,9 +189,9 @@ static struct at91_twi_pdata *at91_twi_get_driver_data(
> > match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
> > if (!match)
> > return NULL;
> > - return (struct at91_twi_pdata *)match->data;
> > + return match->data;
> > }
> > - return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
> > + return (const void *) platform_get_device_id(pdev)->driver_data;
>
> the const's always confuse me... do you get an error here? Is
> this cast really needed?
platform_device_id.driver_data is an ulong, not a void pointer. So, the
cast is needed. It could be just (void *), but I think it's better to
document the constness in the code.
--
Michał Mirosław