2023-07-21 13:31:59

by Andy Shevchenko

[permalink] [raw]
Subject: Re: [PATCH v3 01/42] gpio: ep93xx: split device in multiple

On Thu, Jul 20, 2023 at 02:29:01PM +0300, Nikita Shubin via B4 Relay wrote:
> From: Nikita Shubin <[email protected]>
>
> This prepares ep93xx SOC gpio to convert into device tree driver:
> - dropped banks and legacy defines
> - split AB IRQ and make it shared
>
> We are relying on IRQ number information A, B ports have single shared
> IRQ, while F port have dedicated IRQ for each line.
>
> Also we had to split single ep93xx platform_device into multiple, one
> for each port, without this we can't do a full working transition from
> legacy platform code into device tree capable. All GPIO_LOOKUP were
> change to match new chip namings.

...

> -static void ep93xx_gpio_ab_irq_handler(struct irq_desc *desc)
> +static u32 ep93xx_gpio_ab_irq_handler(struct gpio_chip *gc)
> {
> - struct gpio_chip *gc = irq_desc_get_handler_data(desc);
> - struct ep93xx_gpio *epg = gpiochip_get_data(gc);
> - struct irq_chip *irqchip = irq_desc_get_chip(desc);
> + struct ep93xx_gpio_irq_chip *eic = to_ep93xx_gpio_irq_chip(gc);
> unsigned long stat;
> int offset;
>
> - chained_irq_enter(irqchip, desc);
> -
> - /*
> - * Dispatch the IRQs to the irqdomain of each A and B
> - * gpiochip irqdomains depending on what has fired.
> - * The tricky part is that the IRQ line is shared
> - * between bank A and B and each has their own gpiochip.
> - */
> - stat = readb(epg->base + EP93XX_GPIO_A_INT_STATUS);
> + stat = readb(eic->base + EP93XX_INT_STATUS_OFFSET);
> for_each_set_bit(offset, &stat, 8)
> - generic_handle_domain_irq(epg->gc[0].gc.irq.domain,
> - offset);
> + generic_handle_domain_irq(gc->irq.domain, offset);
>
> - stat = readb(epg->base + EP93XX_GPIO_B_INT_STATUS);
> - for_each_set_bit(offset, &stat, 8)
> - generic_handle_domain_irq(epg->gc[1].gc.irq.domain,
> - offset);
> + return stat;
> +}
>
> - chained_irq_exit(irqchip, desc);
> +static irqreturn_t ep93xx_ab_irq_handler(int irq, void *dev_id)
> +{
> + return IRQ_RETVAL(ep93xx_gpio_ab_irq_handler(dev_id));
> }
>
> static void ep93xx_gpio_f_irq_handler(struct irq_desc *desc)
> {
> - /*
> - * map discontiguous hw irq range to continuous sw irq range:
> - *
> - * IRQ_EP93XX_GPIO{0..7}MUX -> EP93XX_GPIO_LINE_F{0..7}
> - */
> struct irq_chip *irqchip = irq_desc_get_chip(desc);
> - unsigned int irq = irq_desc_get_irq(desc);
> - int port_f_idx = (irq & 7) ^ 4; /* {20..23,48..51} -> {0..7} */
> - int gpio_irq = EP93XX_GPIO_F_IRQ_BASE + port_f_idx;
> + struct gpio_chip *gc = irq_desc_get_handler_data(desc);
> + struct gpio_irq_chip *gic = &gc->irq;
> + unsigned int parent = irq_desc_get_irq(desc);
> + unsigned int i;
>
> chained_irq_enter(irqchip, desc);
> - generic_handle_irq(gpio_irq);
> + for (i = 0; i < gic->num_parents; i++)
> + if (gic->parents[i] == parent)
> + break;
> +
> + if (i < gic->num_parents)
> + generic_handle_irq(irq_find_mapping(gc->irq.domain, i));

Can we use

generic_handle_domain_irq(gc->irq.domain, i);

here as well?

> chained_irq_exit(irqchip, desc);
> }

...

> - int offset = d->irq & 7;
> + int offset = irqd_to_hwirq(d);

irq_hw_number_t ?

> irq_flow_handler_t handler;

...

> + int ret, irq, i = 0;

What do you need this assignment for?

...

> + ret = devm_request_irq(dev, irq,
> + ep93xx_ab_irq_handler,

It can be located on the previous line.

> + IRQF_SHARED, gc->label, gc);
> + if (ret)
> + return dev_err_probe(dev, ret, "error requesting IRQ : %d\n", irq);

Drop duplicating word 'error' in the message.
Space is not needed before colon.

...

> + /* TODO: replace with handle_bad_irq once we are fully hierarchical */

To be pedantic: handle_bad_irq()

> + gc->label = dev_name(&pdev->dev);
> + if (platform_irq_count(pdev) > 0) {
> + dev_dbg(&pdev->dev, "setting up irqs for %s\n", dev_name(&pdev->dev));
> + ret = ep93xx_setup_irqs(pdev, egc);
> + if (ret)

> + dev_err(&pdev->dev, "setup irqs failed for %s\n", dev_name(&pdev->dev));

What's the point to print dev name twice? Esp. taking into account
gc->label assignment above. Why not use dev_err_probe() to unify
the format of the messages from ->probe()?

--
With Best Regards,
Andy Shevchenko