[PATCH v2] realtek: fix RTL8231 gpio expander for high GPIOs

[Sander Vanheule]

On Mon, 2021-09-20 at 20:13 +0300, Paul Fertser wrote:
> GPIOs > 31 require special handling. This patch fixes both the
> initialisation and direction get/set operations.
> 
> Signed-off-by: Paul Fertser <fercerpav at gmail.com>
> ---
> 
> Notes:
>     Changes from v1:
>      - Do not modify high GPIOs direction bits on init

Thanks for the update.

Reviewed-by: Sander Vanheule <sander at svanheule.net>

> 
>  .../realtek/files-5.4/drivers/gpio/gpio-rtl8231.c   | 13 ++++++++-----
>  1 file changed, 8 insertions(+), 5 deletions(-)
> 
> diff --git a/target/linux/realtek/files-5.4/drivers/gpio/gpio-rtl8231.c
> b/target/linux/realtek/files-5.4/drivers/gpio/gpio-rtl8231.c
> index 031f60f5307c..a8ffcdc31368 100644
> --- a/target/linux/realtek/files-5.4/drivers/gpio/gpio-rtl8231.c
> +++ b/target/linux/realtek/files-5.4/drivers/gpio/gpio-rtl8231.c
> @@ -106,12 +106,11 @@ static int rtl8231_pin_dir(struct rtl8231_gpios *gpios, u32 gpio,
> u32 dir)
>         u32 v;
>         int pin_sel_addr = RTL8231_GPIO_PIN_SEL(gpio);
>         int pin_dir_addr = RTL8231_GPIO_DIR(gpio);
> -       int pin = gpio % 16;
> -       int dpin = pin;
> +       int dpin = gpio % 16;
>  
>         if (gpio > 31) {
>                 pr_debug("WARNING: HIGH pin\n");
> -               dpin = pin << 5;
> +               dpin += 5;
>                 pin_dir_addr = pin_sel_addr;
>         }
>  
> @@ -140,7 +139,7 @@ static int rtl8231_pin_dir_get(struct rtl8231_gpios *gpios, u32
> gpio, u32 *dir)
>  
>         if (gpio > 31) {
>                 pin_dir_addr = RTL8231_GPIO_PIN_SEL(gpio);
> -               pin = pin << 5;
> +               pin += 5;
>         }
>  
>         v = rtl8231_read(gpios, pin_dir_addr);
> @@ -240,6 +239,8 @@ void rtl8231_gpio_set(struct gpio_chip *gc, unsigned int offset, int
> value)
>  
>  int rtl8231_init(struct rtl8231_gpios *gpios)
>  {
> +       u32 v;
> +
>         pr_info("%s called, MDIO bus ID: %d\n", __func__, gpios->smi_bus_id);
>  
>         gpios->reg_cached = 0;
> @@ -253,9 +254,11 @@ int rtl8231_init(struct rtl8231_gpios *gpios)
>                 sw_w32_mask(3, 1, RTL838X_DMY_REG5);
>         }
>  
> -       /*Select GPIO functionality for pins 0-15, 16-31 and 32-37 */
> +       /* Select GPIO functionality for pins 0-34 */
>         rtl8231_write(gpios, RTL8231_GPIO_PIN_SEL(0), 0xffff);
>         rtl8231_write(gpios, RTL8231_GPIO_PIN_SEL(16), 0xffff);
> +       v = rtl8231_read(gpios, RTL8231_GPIO_PIN_SEL(32));
> +       rtl8231_write(gpios, RTL8231_GPIO_PIN_SEL(32), v | 0x7);
>  
>         return 0;
>  }