[PATCH 4/9] pinctrl: meson: allow gpio to request irq
From: Linus Walleij <hidden>
Date: 2016-10-20 19:21:09
Also in:
linux-amlogic, linux-devicetree, linux-gpio, lkml
On Wed, Oct 19, 2016 at 12:08 PM, Jerome Brunet [off-list ref] wrote:
Add the ability for gpio to request irq from the gpio interrupt controller if present. We have to specificaly that the parent interrupt controller is the gpio interrupt controller because gpio on meson SoCs can't generate interrupt directly on the GIC. Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
(...)
quoted hunk ↗ jump to hunk
+ select IRQ_DOMAIN select OF_GPIO + select OF_IRQ
(...)
quoted hunk ↗ jump to hunk
+static int meson_gpio_to_hwirq(struct meson_bank *bank, unsigned int offset) +{ + unsigned int hwirq; + + if (bank->irq_first < 0) + /* this bank cannot generate irqs */ + return -1; + + hwirq = offset - bank->first + bank->irq_first; + + if (hwirq > bank->irq_last) + /* this pin cannot generate irqs */ + return -1; + + return hwirq; +}
This is reimplementing irqdomain.
+static int meson_gpio_to_irq(struct gpio_chip *chip, unsigned int offset)
+{(...)
quoted hunk ↗ jump to hunk
+ hwirq = meson_gpio_to_hwirq(bank, offset); + if (hwirq < 0) { + dev_dbg(pc->dev, "no interrupt for pin %u\n", offset); + return 0; + }
Isn't this usecase (also as described in the cover letter) a textbook example of when you should be using hierarchical irqdomain? Please check with Marc et al on hierarchical irqdomains. Yours, Linus Walleij