[v7 2/2] gpio: aspeed: Add SGPIO driver

[Linus Walleij]

Hi Hongwei,

thanks for your patch!

I have now merged the bindings so you only need to respin
this patch.

On Wed, Jul 31, 2019 at 10:02 PM Hongwei Zhang <hongweiz at ami.com> wrote:

> Add SGPIO driver support for Aspeed AST2500 SoC.
>
> Signed-off-by: Hongwei Zhang <hongweiz at ami.com>
> Reviewed-by:   Andrew Jeffery <andrew at aj.id.au>

I guess I need to go with this, there are some minor things
I still want to be fixed:

> +static void __aspeed_sgpio_set(struct gpio_chip *gc, unsigned int offset, int val)

I don't like __underscore_functions because their semantic
is ambiguous.

Rename this something like aspeed_sgpio_commit() or
whatever best fits the actual use.

> +static int aspeed_sgpio_setup_irqs(struct aspeed_sgpio *gpio,
> +                                  struct platform_device *pdev)
> +{
(...)
> +       rc = gpiochip_irqchip_add(&gpio->chip, &aspeed_sgpio_irqchip,
> +                                 0, handle_bad_irq, IRQ_TYPE_NONE);
(...)
> +       gpiochip_set_chained_irqchip(&gpio->chip, &aspeed_sgpio_irqchip,
> +                                    gpio->irq, aspeed_sgpio_irq_handler);

We do not set up chained irqchips like this anymore, sorry.

I am currently rewriting all existing chained drivers to pass
an initialized irqchip when registering the whole gpio chip.
See drivers/gpio/TODO.

Here are examples:
https://lore.kernel.org/linux-gpio/20190811080539.15647-1-linus.walleij@linaro.org/
https://lore.kernel.org/linux-gpio/20190812132554.18313-1-linus.walleij@linaro.org/

> +       /* set all SGPIO pins as input (1). */
> +       memset(gpio->dir_in, 0xff, sizeof(gpio->dir_in));

Do the irqchip set-up here, before adding the gpio_chip.

> +       rc = devm_gpiochip_add_data(&pdev->dev, &gpio->chip, gpio);
> +       if (rc < 0)
> +               return rc;
> +
> +       return aspeed_sgpio_setup_irqs(gpio, pdev);

Yours,
Linus Walleij