Re: [PATCH] pinctrl: sh-pfc: r8a77970: remove SH_PFC_PIN_CFG_DRIVE_STRENGTH flag

[Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>]

CC Sergei,

Thanks for your patch!

On Mon, Jul 2, 2018 at 10:06 AM Niklas Söderlund
<niklas.soderlund+renesas@xxxxxxxxxxxx> wrote:
> The datasheet do not document any registers to control drive strength,

does

> and no drive strength registers are for this reason described for this
> SoC. The flag indicating that drive strength can be controlled are

flags

> however set for some pins in the driver.
>
> This leads to a NULL pointer dereference when the sh-pfc core tries to
> access the struct describing the drive strength registers, for example
> when reading the sysfs file pinconf-pins.
>
> Fix this by removing the SH_PFC_PIN_CFG_DRIVE_STRENGTH from all pins.
>
> Signed-off-by: Niklas Söderlund <niklas.soderlund+renesas@xxxxxxxxxxxx>

Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>

I'll wait a bit for Sergei's response.
Perhaps his version of the datasheet does document drive strength registers?

> --- a/drivers/pinctrl/sh-pfc/pfc-r8a77970.c
> +++ b/drivers/pinctrl/sh-pfc/pfc-r8a77970.c
> @@ -21,15 +21,13 @@
>  #include "core.h"
>  #include "sh_pfc.h"
>
> -#define CFG_FLAGS SH_PFC_PIN_CFG_DRIVE_STRENGTH
> -
>  #define CPU_ALL_PORT(fn, sfx)                                          \
> -       PORT_GP_CFG_22(0, fn, sfx, CFG_FLAGS | SH_PFC_PIN_CFG_IO_VOLTAGE), \
> -       PORT_GP_CFG_28(1, fn, sfx, CFG_FLAGS),                          \
> -       PORT_GP_CFG_17(2, fn, sfx, CFG_FLAGS | SH_PFC_PIN_CFG_IO_VOLTAGE), \
> -       PORT_GP_CFG_17(3, fn, sfx, CFG_FLAGS | SH_PFC_PIN_CFG_IO_VOLTAGE), \
> -       PORT_GP_CFG_6(4,  fn, sfx, CFG_FLAGS),                          \
> -       PORT_GP_CFG_15(5, fn, sfx, CFG_FLAGS)
> +       PORT_GP_CFG_22(0, fn, sfx, SH_PFC_PIN_CFG_IO_VOLTAGE),          \
> +       PORT_GP_28(1, fn, sfx),                                         \
> +       PORT_GP_CFG_17(2, fn, sfx, SH_PFC_PIN_CFG_IO_VOLTAGE),          \
> +       PORT_GP_CFG_17(3, fn, sfx, SH_PFC_PIN_CFG_IO_VOLTAGE),          \
> +       PORT_GP_6(4,  fn, sfx),                                         \
> +       PORT_GP_15(5, fn, sfx)
>  /*
>   * F_() : just information
>   * FM() : macro for FN_xxx / xxx_MARK

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds
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