[PATCH v6 6/9] pinctrl: meson: add support for GPIO interrupts
Heiner Kallweit
hkallweit1 at gmail.com
Thu Jun 8 12:39:14 PDT 2017
Add support for GPIO interrupts and make use of the just introduced
irqchip driver handling the GPIO interrupt-controller.
Signed-off-by: Heiner Kallweit <hkallweit1 at gmail.com>
---
v5:
- changed Kconfig entry based on Neil's suggestion
- extended comments
- fixed indentation
v6:
- no changes
---
drivers/pinctrl/Kconfig | 1 +
drivers/pinctrl/meson/pinctrl-meson.c | 170 +++++++++++++++++++++++++++++++++-
2 files changed, 170 insertions(+), 1 deletion(-)
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 7ae04a97..86834dea 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -166,6 +166,7 @@ config PINCTRL_MESON
select PINCONF
select GENERIC_PINCONF
select GPIOLIB
+ select GPIOLIB_IRQCHIP
select OF_GPIO
select REGMAP_MMIO
diff --git a/drivers/pinctrl/meson/pinctrl-meson.c b/drivers/pinctrl/meson/pinctrl-meson.c
index 66ed70c1..7bacd4e3 100644
--- a/drivers/pinctrl/meson/pinctrl-meson.c
+++ b/drivers/pinctrl/meson/pinctrl-meson.c
@@ -62,6 +62,8 @@
#include "../pinctrl-utils.h"
#include "pinctrl-meson.h"
+static struct irq_domain *meson_pinctrl_irq_domain;
+
/**
* meson_get_bank() - find the bank containing a given pin
*
@@ -497,6 +499,154 @@ static int meson_gpio_get(struct gpio_chip *chip, unsigned gpio)
return !!(val & BIT(bit));
}
+static struct meson_pinctrl *meson_gpio_data_to_pc(struct irq_data *data)
+{
+ struct gpio_chip *chip = irq_data_get_irq_chip_data(data);
+
+ return gpiochip_get_data(chip);
+}
+
+static int meson_gpio_bank_hwirq(struct meson_bank *bank, unsigned int offset)
+{
+ int hwirq;
+
+ if (bank->irq_first < 0)
+ /* this bank cannot generate irqs */
+ return 0;
+
+ hwirq = offset - bank->first + bank->irq_first;
+
+ if (hwirq > bank->irq_last)
+ /* this pin cannot generate irqs */
+ return 0;
+
+ return hwirq;
+}
+
+static int meson_gpio_to_hwirq(struct irq_data *data)
+{
+ struct meson_pinctrl *pc = meson_gpio_data_to_pc(data);
+ unsigned int offset = data->hwirq;
+ struct meson_bank *bank;
+ int hwirq, ret;
+
+ offset += pc->data->pin_base;
+
+ ret = meson_get_bank(pc, offset, &bank);
+ if (ret)
+ return ret;
+
+ hwirq = meson_gpio_bank_hwirq(bank, offset);
+ if (!hwirq)
+ dev_dbg(pc->dev, "no interrupt for pin %u\n", offset);
+
+ return hwirq;
+}
+
+static void meson_gpio_irq_handler(struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ struct irq_data *gpio_irq_data = irq_desc_get_handler_data(desc);
+
+ chained_irq_enter(chip, desc);
+
+ if (gpio_irq_data)
+ generic_handle_irq(gpio_irq_data->irq);
+
+ chained_irq_exit(chip, desc);
+}
+
+static void meson_gpio_irq_unmask(struct irq_data *data) {}
+static void meson_gpio_irq_mask(struct irq_data *data) {}
+
+static void meson_gpio_irq_shutdown(struct irq_data *data)
+{
+ int hwirq = meson_gpio_to_hwirq(data);
+ int irq;
+
+ if (hwirq <= 0)
+ return;
+
+ /*
+ * In case of IRQ_TYPE_EDGE_BOTH we need two parent interrupts,
+ * one for each edge. That's due to HW constraints.
+ * We use format 2 * GPIO_HWIRQ +(0|1) for the hwirq, so we can
+ * have one GPIO_HWIRQ twice and derive the GPIO_HWIRQ from hwirq
+ * by shifting hwirq one bit to the right.
+ */
+ irq = irq_find_mapping(meson_pinctrl_irq_domain, hwirq * 2);
+ if (irq) {
+ irq_set_chained_handler_and_data(irq, handle_bad_irq, NULL);
+ irq_domain_free_irqs(irq, 1);
+ }
+
+ irq = irq_find_mapping(meson_pinctrl_irq_domain, hwirq * 2 + 1);
+ if (irq) {
+ irq_set_chained_handler_and_data(irq, handle_bad_irq, NULL);
+ irq_domain_free_irqs(irq, 1);
+ }
+}
+
+static int meson_gpio_irq_set_type(struct irq_data *data, unsigned int type)
+{
+ int hwirq = meson_gpio_to_hwirq(data);
+ struct irq_fwspec fwspec;
+ int irq, irq2, num_slots;
+
+ if (irqd_is_activated(data))
+ return -EBUSY;
+
+ if (hwirq < 0)
+ return hwirq;
+
+ if (!hwirq)
+ return -ENXIO;
+
+ fwspec.fwnode = meson_pinctrl_irq_domain->fwnode;
+ fwspec.param_count = 2;
+
+ /*
+ * The chip can create an interrupt for either rising or falling edge
+ * only. Therefore use two interrupts in case of IRQ_TYPE_EDGE_BOTH,
+ * first for falling edge and second one for rising edge.
+ */
+ num_slots = (type == IRQ_TYPE_EDGE_BOTH) ? 2 : 1;
+
+ /* see comment in meson_gpio_irq_shutdown why we shift one bit here */
+ fwspec.param[0] = hwirq << 1;
+ if (num_slots == 1)
+ fwspec.param[1] = type;
+ else
+ fwspec.param[1] = IRQ_TYPE_EDGE_FALLING;
+
+ irq = irq_create_fwspec_mapping(&fwspec);
+ if (!irq)
+ return -EINVAL;
+
+ irq_set_chained_handler_and_data(irq, meson_gpio_irq_handler, data);
+
+ if (num_slots > 1) {
+ fwspec.param[0]++;
+ fwspec.param[1] = IRQ_TYPE_EDGE_RISING;
+ irq2 = irq_create_fwspec_mapping(&fwspec);
+ if (!irq2) {
+ irq_domain_free_irqs(irq, 1);
+ return -EINVAL;
+ }
+ irq_set_chained_handler_and_data(irq2, meson_gpio_irq_handler, data);
+ }
+
+ return 0;
+}
+
+static struct irq_chip meson_gpio_irq_chip = {
+ .name = "GPIO",
+ .irq_set_type = meson_gpio_irq_set_type,
+ .irq_mask = meson_gpio_irq_mask,
+ .irq_unmask = meson_gpio_irq_unmask,
+ .irq_shutdown = meson_gpio_irq_shutdown,
+};
+
static const struct of_device_id meson_pinctrl_dt_match[] = {
{
.compatible = "amlogic,meson8-cbus-pinctrl",
@@ -558,7 +708,8 @@ static int meson_gpiolib_register(struct meson_pinctrl *pc)
return ret;
}
- return 0;
+ return gpiochip_irqchip_add(&pc->chip, &meson_gpio_irq_chip, 0,
+ handle_simple_irq, IRQ_TYPE_NONE);
}
static struct regmap_config meson_regmap_config = {
@@ -637,6 +788,23 @@ static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc,
return PTR_ERR(pc->reg_gpio);
}
+ if (!meson_pinctrl_irq_domain) {
+ np = of_find_compatible_node(NULL, NULL, "amlogic,meson-gpio-intc");
+ if (!np) {
+ dev_err(pc->dev, "interrupt controller DT node not found\n");
+ return -EINVAL;
+ }
+
+ meson_pinctrl_irq_domain = irq_find_host(np);
+ if (!meson_pinctrl_irq_domain) {
+ dev_err(pc->dev, "interrupt controller not found\n");
+ of_node_put(np);
+ return -EINVAL;
+ }
+
+ of_node_put(np);
+ }
+
return 0;
}
--
2.13.0
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