[PATCH v3.1 11/21] ARM: pxa: support ICP DAS LP-8x4x FPGA irq

Linus Walleij
2014-01-15T07:46:47Z

This is looking much better!

On Fri, Jan 10, 2014 at 12:07 AM, Sergei Ianovich <ynvich@gmail.com> wrote:

> +++ b/drivers/irqchip/irq-lp8x4x.c
(...)

You could add some kerneldoc to this following struct (OK nitpick, but
still nice, especially for the last two variables).

> +struct lp8x4x_irq_data {
> + void *base;
> + struct irq_domain *domain;
> + unsigned long num_irq;
> + unsigned char irq_sys_enabled;
> + unsigned char irq_high_enabled;
> +};
> +
> +static void lp8x4x_mask_irq(struct irq_data *d)
> +{
> + unsigned mask;
> + unsigned long irq = d->hwirq;

Name the local variable hwirq too so we know what it is.

> + struct lp8x4x_irq_data *host = irq_data_get_irq_chip_data(d);
> +
> + if (!host) {
> + pr_err("lp8x4x: missing host data for irq %i\n", d->irq);
> + return;
> + }
> +
> + if (irq >= host->num_irq) {
> + pr_err("lp8x4x: wrong irq handler for irq %i\n", d->irq);
> + return;
> + }

This is on the hotpath. Do you *really* need these two checks?

(...)
> +static void lp8x4x_unmask_irq(struct irq_data *d)
> +{
> + unsigned mask;
> + unsigned long irq = d->hwirq;

Name the variable "hwirq".

> + struct lp8x4x_irq_data *host = irq_data_get_irq_chip_data(d);
> +
> + if (!host) {
> + pr_err("lp8x4x: missing host data for irq %i\n", d->irq);
> + return;
> + }
> +
> + if (irq >= host->num_irq) {
> + pr_err("lp8x4x: wrong irq handler for irq %i\n", d->irq);
> + return;
> + }

Again overzealous error checks.

(...)
> +static void lp8x4x_irq_handler(unsigned int irq, struct irq_desc *desc)
> +{
> + int n;
> + unsigned long mask;
> + struct irq_chip *chip = irq_desc_get_chip(desc);
> + struct lp8x4x_irq_data *host = irq_desc_get_handler_data(desc);
> +
> + if (!host)
> + return;

I don't think this happens either?

> + chained_irq_enter(chip, desc);
> +
> + for (;;) {
> + mask = ioread8(host->base + CLRHILVINT) & 0xff;
> + mask |= (ioread8(host->base + SECOINT) & SECOINT_MASK) << 8;
> + mask |= (ioread8(host->base + PRIMINT) & PRIMINT_MASK) << 8;
> + mask &= host->irq_high_enabled | (host->irq_sys_enabled << 8);
> + if (mask == 0)
> + break;
> + for_each_set_bit(n, &mask, BITS_PER_LONG)
> + generic_handle_irq(irq_find_mapping(host->domain, n));
> + }

I like the looks of this.

If you fix this:
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>

Yours,
Linus Walleij