Re: [PATCH net-next 5/6] net: dsa: realtek-smi: add rtl8365mb subdriver for RTL8365MB-VC

[Linus Walleij]

On Tue, Oct 12, 2021 at 2:37 PM Alvin Šipraga <alvin@xxxxxxx> wrote:

> This patch adds a realtek-smi subdriver for the RTL8365MB-VC 4+1 port
> 10/100/1000M switch controller. The driver has been developed based on a
> GPL-licensed OS-agnostic Realtek vendor driver known as rtl8367c found
> in the OpenWrt source tree.
(...)
> Co-developed-by: Michael Rasmussen <mir@xxxxxxxxxxxxxxx>
> Signed-off-by: Michael Rasmussen <mir@xxxxxxxxxxxxxxx>
> Signed-off-by: Alvin Šipraga <alsi@xxxxxxxxxxxxxxx>

Overall this driver looks very good :)

Some minor nits below:

> +static irqreturn_t rtl8365mb_irq(int irq, void *data)
> +{
(...)
> +       if (!line_changes)
> +               goto out_none;
> +
> +       while (line_changes) {
> +               int line = __ffs(line_changes);
> +               int child_irq;
> +
> +               line_changes &= ~BIT(line);
> +
> +               child_irq = irq_find_mapping(smi->irqdomain, line);
> +               handle_nested_irq(child_irq);
> +       }

What about just:

for_each_set_bit(offset, &line_changes, 32) {
  child_irq = irq_find_mapping(smi->irqdomain, line);
  handle_nested_irq(child_irq);
}

?

I don't know how many or which bits are valid IRQs, 16 maybe rather
than 32.

> +static struct irq_chip rtl8365mb_irq_chip = {
> +       .name = "rtl8365mb",
> +       /* The hardware doesn't support masking IRQs on a per-port basis */
> +};

I would rathe make this a dynamically allocated struct inside
struct rtl8365mb, so the irqchip lives with the instance of the
chip. (Which is nice if there would happen to be two of these
chips in a system.)

> +static int _rtl8365mb_irq_enable(struct realtek_smi *smi, bool enable)

I'm personally a bit allergic to _rand_underscore_naming, as sometimes
that means "inner function" and sometimes it means "compiler intrinsic"
I would just name it rtl8365mb_irq_config_commit()

(no strong opinion)

> +       /* Configure chip interrupt signal polarity */
> +       irq_trig = irqd_get_trigger_type(irq_get_irq_data(irq));

Nice that you preserve this edge trigger config from the machine
description (DT)!

With this fixed or not (your preference)
Reviewed-by: Linus Walleij <linus.walleij@xxxxxxxxxx>

Yours,
Linus Walleij