pinctrl: st: Add Interrupt support
This patch add interrupt support to the pincontroller driver.
ST Pincontroller GPIO bank can have one of the two possible types of
interrupt-wirings.
First type is via irqmux, single interrupt is used by multiple gpio
banks. This reduces number of overall interrupts numbers required. All
these banks belong to a single pincontroller.
_________
| |----> [gpio-bank (n) ]
| |----> [gpio-bank (n + 1)]
[irqN]-- | irq-mux |----> [gpio-bank (n + 2)]
| |----> [gpio-bank (... )]
|_________|----> [gpio-bank (n + 7)]
Second type has a dedicated interrupt per gpio bank.
[irqN]----> [gpio-bank (n)]
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/pinctrl/pinctrl-st.c b/drivers/pinctrl/pinctrl-st.c
index 320c273..51e4f3a 100644
--- a/drivers/pinctrl/pinctrl-st.c
+++ b/drivers/pinctrl/pinctrl-st.c
@@ -13,7 +13,12 @@
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/irqdesc.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip/chained_irq.h>
#include <linux/of.h>
+#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <linux/of_address.h>
#include <linux/regmap.h>
@@ -271,6 +276,7 @@
struct pinctrl_gpio_range range;
void __iomem *base;
struct st_pio_control pc;
+ struct irq_domain *domain;
};
struct st_pinctrl {
@@ -284,6 +290,7 @@
int ngroups;
struct regmap *regmap;
const struct st_pctl_data *data;
+ void __iomem *irqmux_base;
};
/* SOC specific data */
@@ -1200,6 +1207,130 @@
return 0;
}
+static int st_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+ struct st_gpio_bank *bank = gpio_chip_to_bank(chip);
+ int irq = -ENXIO;
+
+ if (offset < chip->ngpio)
+ irq = irq_find_mapping(bank->domain, offset);
+
+ dev_info(chip->dev, "%s: request IRQ for GPIO %d, return %d\n",
+ chip->label, offset + chip->base, irq);
+ return irq;
+}
+
+static void st_gpio_irq_mask(struct irq_data *d)
+{
+ struct st_gpio_bank *bank = irq_data_get_irq_chip_data(d);
+
+ writel(BIT(d->hwirq), bank->base + REG_PIO_CLR_PMASK);
+}
+
+static void st_gpio_irq_unmask(struct irq_data *d)
+{
+ struct st_gpio_bank *bank = irq_data_get_irq_chip_data(d);
+
+ writel(BIT(d->hwirq), bank->base + REG_PIO_SET_PMASK);
+}
+
+static unsigned int st_gpio_irq_startup(struct irq_data *d)
+{
+ struct st_gpio_bank *bank = irq_data_get_irq_chip_data(d);
+
+ if (gpio_lock_as_irq(&bank->gpio_chip, d->hwirq))
+ dev_err(bank->gpio_chip.dev,
+ "unable to lock HW IRQ %lu for IRQ\n",
+ d->hwirq);
+
+ st_gpio_irq_unmask(d);
+
+ return 0;
+}
+
+static void st_gpio_irq_shutdown(struct irq_data *d)
+{
+ struct st_gpio_bank *bank = irq_data_get_irq_chip_data(d);
+
+ st_gpio_irq_mask(d);
+ gpio_unlock_as_irq(&bank->gpio_chip, d->hwirq);
+}
+
+static int st_gpio_irq_set_type(struct irq_data *d, unsigned type)
+{
+ struct st_gpio_bank *bank = irq_data_get_irq_chip_data(d);
+ unsigned long flags;
+ int comp, pin = d->hwirq;
+ u32 val;
+
+ switch (type) {
+ case IRQ_TYPE_LEVEL_HIGH:
+ comp = 0;
+ break;
+ case IRQ_TYPE_LEVEL_LOW:
+ comp = 1;
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ val = readl(bank->base + REG_PIO_PCOMP);
+ val &= ~BIT(pin);
+ val |= (comp << pin);
+ writel(val, bank->base + REG_PIO_PCOMP);
+
+ return 0;
+}
+
+static void __gpio_irq_handler(struct st_gpio_bank *bank)
+{
+ unsigned long port_in, port_mask, port_comp, active_irqs;
+ int n;
+
+ for (;;) {
+ port_in = readl(bank->base + REG_PIO_PIN);
+ port_comp = readl(bank->base + REG_PIO_PCOMP);
+ port_mask = readl(bank->base + REG_PIO_PMASK);
+
+ active_irqs = (port_in ^ port_comp) & port_mask;
+
+ if (active_irqs == 0)
+ break;
+
+ for_each_set_bit(n, &active_irqs, BITS_PER_LONG) {
+ generic_handle_irq(irq_find_mapping(bank->domain, n));
+ }
+ }
+}
+
+static void st_gpio_irq_handler(unsigned irq, struct irq_desc *desc)
+{
+ /* interrupt dedicated per bank */
+ struct irq_chip *chip = irq_get_chip(irq);
+ struct st_gpio_bank *bank = irq_get_handler_data(irq);
+
+ chained_irq_enter(chip, desc);
+ __gpio_irq_handler(bank);
+ chained_irq_exit(chip, desc);
+}
+
+static void st_gpio_irqmux_handler(unsigned irq, struct irq_desc *desc)
+{
+ struct irq_chip *chip = irq_get_chip(irq);
+ struct st_pinctrl *info = irq_get_handler_data(irq);
+ unsigned long status;
+ int n;
+
+ chained_irq_enter(chip, desc);
+
+ status = readl(info->irqmux_base);
+
+ for_each_set_bit(n, &status, ST_GPIO_PINS_PER_BANK)
+ __gpio_irq_handler(&info->banks[n]);
+
+ chained_irq_exit(chip, desc);
+}
+
static struct gpio_chip st_gpio_template = {
.request = st_gpio_request,
.free = st_gpio_free,
@@ -1210,6 +1341,34 @@
.ngpio = ST_GPIO_PINS_PER_BANK,
.of_gpio_n_cells = 1,
.of_xlate = st_gpio_xlate,
+ .to_irq = st_gpio_to_irq,
+};
+
+static struct irq_chip st_gpio_irqchip = {
+ .name = "GPIO",
+ .irq_mask = st_gpio_irq_mask,
+ .irq_unmask = st_gpio_irq_unmask,
+ .irq_set_type = st_gpio_irq_set_type,
+ .irq_startup = st_gpio_irq_startup,
+ .irq_shutdown = st_gpio_irq_shutdown,
+};
+
+static int st_gpio_irq_domain_map(struct irq_domain *h,
+ unsigned int virq, irq_hw_number_t hw)
+{
+ struct st_gpio_bank *bank = h->host_data;
+
+ irq_set_chip(virq, &st_gpio_irqchip);
+ irq_set_handler(virq, handle_level_irq);
+ set_irq_flags(virq, IRQF_VALID);
+ irq_set_chip_data(virq, bank);
+
+ return 0;
+}
+
+static struct irq_domain_ops st_gpio_irq_ops = {
+ .map = st_gpio_irq_domain_map,
+ .xlate = irq_domain_xlate_twocell,
};
static int st_gpiolib_register_bank(struct st_pinctrl *info,
@@ -1219,8 +1378,8 @@
struct pinctrl_gpio_range *range = &bank->range;
struct device *dev = info->dev;
int bank_num = of_alias_get_id(np, "gpio");
- struct resource res;
- int err;
+ struct resource res, irq_res;
+ int gpio_irq = 0, err, i;
if (of_address_to_resource(np, 0, &res))
return -ENODEV;
@@ -1248,6 +1407,51 @@
}
dev_info(dev, "%s bank added.\n", range->name);
+ /**
+ * GPIO bank can have one of the two possible types of
+ * interrupt-wirings.
+ *
+ * First type is via irqmux, single interrupt is used by multiple
+ * gpio banks. This reduces number of overall interrupts numbers
+ * required. All these banks belong to a single pincontroller.
+ * _________
+ * | |----> [gpio-bank (n) ]
+ * | |----> [gpio-bank (n + 1)]
+ * [irqN]-- | irq-mux |----> [gpio-bank (n + 2)]
+ * | |----> [gpio-bank (... )]
+ * |_________|----> [gpio-bank (n + 7)]
+ *
+ * Second type has a dedicated interrupt per each gpio bank.
+ *
+ * [irqN]----> [gpio-bank (n)]
+ */
+
+ if (!of_irq_to_resource(np, 0, &irq_res)) {
+ gpio_irq = irq_res.start;
+ irq_set_chained_handler(gpio_irq, st_gpio_irq_handler);
+ irq_set_handler_data(gpio_irq, bank);
+ }
+
+ if (info->irqmux_base > 0 || gpio_irq > 0) {
+ /* Setup IRQ domain */
+ bank->domain = irq_domain_add_linear(np,
+ ST_GPIO_PINS_PER_BANK,
+ &st_gpio_irq_ops, bank);
+ if (!bank->domain) {
+ dev_err(dev, "Failed to add irq domain for %s\n",
+ np->full_name);
+ } else {
+ for (i = 0; i < ST_GPIO_PINS_PER_BANK; i++) {
+ if (irq_create_mapping(bank->domain, i) < 0)
+ dev_err(dev,
+ "Failed to map IRQ %i\n", i);
+ }
+ }
+
+ } else {
+ dev_info(dev, "No IRQ support for %s bank\n", np->full_name);
+ }
+
return 0;
}
@@ -1276,6 +1480,8 @@
struct device_node *np = pdev->dev.of_node;
struct device_node *child;
int grp_index = 0;
+ int irq = 0;
+ struct resource *res;
st_pctl_dt_child_count(info, np);
if (!info->nbanks) {
@@ -1306,6 +1512,21 @@
}
info->data = of_match_node(st_pctl_of_match, np)->data;
+ irq = platform_get_irq(pdev, 0);
+
+ if (irq > 0) {
+ res = platform_get_resource_byname(pdev,
+ IORESOURCE_MEM, "irqmux");
+ info->irqmux_base = devm_ioremap_resource(&pdev->dev, res);
+
+ if (IS_ERR(info->irqmux_base))
+ return PTR_ERR(info->irqmux_base);
+
+ irq_set_chained_handler(irq, st_gpio_irqmux_handler);
+ irq_set_handler_data(irq, info);
+
+ }
+
pctl_desc->npins = info->nbanks * ST_GPIO_PINS_PER_BANK;
pdesc = devm_kzalloc(&pdev->dev,
sizeof(*pdesc) * pctl_desc->npins, GFP_KERNEL);