The change adds support of LPC18xx/LPC43xx GPIO pin interrupt controller
block within SoC GPIO controller. The new interrupt controller driver
allows to configure and capture edge or level interrupts on 8 arbitrary
selectedinput GPIO pins, and lift the signals to be reported as NVIC rising
edge interrupts. Configuration of a particular GPIO pin to serve as
interrupt and its mapping to an interrupt on NVIC is done by SCU pin
controller, for more details see description of 'nxp,gpio-pin-interrupt'
device tree property of a GPIO pin [1].
>From LPC18xx and LPC43xx User Manuals the GPIO controller consists of
the following blocks:
* GPIO pin interrupt block at 0x40087000, this change adds its support,
* GPIO GROUP0 interrupt block at 0x40088000,
* GPIO GROUP1 interrupt block at 0x40089000,
* GPIO port block at 0x400F4000, it is supported by the original driver.
While all 4 sub-controller blocks have their own I/O addresses, moreover
all 3 interrupt blocks are APB0 peripherals and high-speed GPIO block is
an AHB slave, according to the hardware manual the GPIO controller is
seen as a single block, and 4 sub-controllers have the shared reset signal
RGU #28 and clock to register interface CLK_CPU_GPIO on CCU1.
Likely support of two GPIO group interrupt blocks won't be added in short
term, because the mechanism to mask several interrupt sources is not well
defined.
[1] Documentation/devicetree/bindings/pinctrl/nxp,lpc1850-scu.txt
Signed-off-by: Vladimir Zapolskiy <vz@xxxxxxxxx>
---
drivers/gpio/Kconfig | 1 +
drivers/gpio/gpio-lpc18xx.c | 267 +++++++++++++++++++++++++++++++++++-
2 files changed, 264 insertions(+), 4 deletions(-)
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 833a1b51c948..a1876c39a7b7 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -288,6 +288,7 @@ config GPIO_LPC18XX
tristate "NXP LPC18XX/43XX GPIO support"
default y if ARCH_LPC18XX
depends on OF_GPIO && (ARCH_LPC18XX || COMPILE_TEST)
+ select IRQ_DOMAIN_HIERARCHY
help
Select this option to enable GPIO driver for
NXP LPC18XX/43XX devices.
diff --git a/drivers/gpio/gpio-lpc18xx.c b/drivers/gpio/gpio-lpc18xx.c
index dc33185a89b1..040fb59d06f7 100644
--- a/drivers/gpio/gpio-lpc18xx.c
+++ b/drivers/gpio/gpio-lpc18xx.c
@@ -2,6 +2,7 @@
/*
* GPIO driver for NXP LPC18xx/43xx.
*
+ * Copyright (C) 2018 Vladimir Zapolskiy <vz@xxxxxxxxx>
* Copyright (C) 2015 Joachim Eastwood <manabian@xxxxxxxxx>
*
*/
@@ -9,9 +10,13 @@
#include <linux/clk.h>
#include <linux/gpio/driver.h>
#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/irqchip.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/of_address.h>
#include <linux/of_gpio.h>
+#include <linux/of_irq.h>
#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
@@ -21,13 +26,247 @@
#define LPC18XX_MAX_PORTS 8
#define LPC18XX_PINS_PER_PORT 32
+/* LPC18xx GPIO pin interrupt controller register offsets */
+#define LPC18XX_GPIO_PIN_IC_ISEL 0x00
+#define LPC18XX_GPIO_PIN_IC_IENR 0x04
+#define LPC18XX_GPIO_PIN_IC_SIENR 0x08
+#define LPC18XX_GPIO_PIN_IC_CIENR 0x0c
+#define LPC18XX_GPIO_PIN_IC_IENF 0x10
+#define LPC18XX_GPIO_PIN_IC_SIENF 0x14
+#define LPC18XX_GPIO_PIN_IC_CIENF 0x18
+#define LPC18XX_GPIO_PIN_IC_RISE 0x1c
+#define LPC18XX_GPIO_PIN_IC_FALL 0x20
+#define LPC18XX_GPIO_PIN_IC_IST 0x24
+
+#define NR_LPC18XX_GPIO_PIN_IC_IRQS 8
+
+struct lpc18xx_gpio_pin_ic {
+ void __iomem *base;
+ struct irq_domain *domain;
+ struct raw_spinlock lock;
+};
+
struct lpc18xx_gpio_chip {
struct gpio_chip gpio;
void __iomem *base;
struct clk *clk;
+ struct lpc18xx_gpio_pin_ic *pin_ic;
spinlock_t lock;
};
+static inline void lpc18xx_gpio_pin_ic_isel(struct lpc18xx_gpio_pin_ic *ic,
+ u32 pin, bool set)
+{
+ u32 val = readl_relaxed(ic->base + LPC18XX_GPIO_PIN_IC_ISEL);
+
+ if (set)
+ val &= ~BIT(pin);
+ else
+ val |= BIT(pin);
+
+ writel_relaxed(val, ic->base + LPC18XX_GPIO_PIN_IC_ISEL);
+}
+
+static inline void lpc18xx_gpio_pin_ic_set(struct lpc18xx_gpio_pin_ic *ic,
+ u32 pin, u32 reg)
+{
+ writel_relaxed(BIT(pin), ic->base + reg);
+}
+
+static void lpc18xx_gpio_pin_ic_mask(struct irq_data *d)
+{
+ struct lpc18xx_gpio_pin_ic *ic = d->chip_data;
+ u32 type = irqd_get_trigger_type(d);
+
+ raw_spin_lock(&ic->lock);
+
+ if (type & IRQ_TYPE_LEVEL_MASK || type & IRQ_TYPE_EDGE_RISING)
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_CIENR);
+
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_CIENF);
+
+ raw_spin_unlock(&ic->lock);
+
+ irq_chip_mask_parent(d);
+}
+
+static void lpc18xx_gpio_pin_ic_unmask(struct irq_data *d)
+{
+ struct lpc18xx_gpio_pin_ic *ic = d->chip_data;
+ u32 type = irqd_get_trigger_type(d);
+
+ raw_spin_lock(&ic->lock);
+
+ if (type & IRQ_TYPE_LEVEL_MASK || type & IRQ_TYPE_EDGE_RISING)
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_SIENR);
+
+ if (type & IRQ_TYPE_EDGE_FALLING)
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_SIENF);
+
+ raw_spin_unlock(&ic->lock);
+
+ irq_chip_unmask_parent(d);
+}
+
+static void lpc18xx_gpio_pin_ic_eoi(struct irq_data *d)
+{
+ struct lpc18xx_gpio_pin_ic *ic = d->chip_data;
+ u32 type = irqd_get_trigger_type(d);
+
+ raw_spin_lock(&ic->lock);
+
+ if (type & IRQ_TYPE_EDGE_BOTH)
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_IST);
+
+ raw_spin_unlock(&ic->lock);
+
+ irq_chip_eoi_parent(d);
+}
+
+static int lpc18xx_gpio_pin_ic_set_type(struct irq_data *d, unsigned int type)
+{
+ struct lpc18xx_gpio_pin_ic *ic = d->chip_data;
+
+ raw_spin_lock(&ic->lock);
+
+ if (type & IRQ_TYPE_LEVEL_HIGH) {
+ lpc18xx_gpio_pin_ic_isel(ic, d->hwirq, true);
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_SIENF);
+ } else if (type & IRQ_TYPE_LEVEL_LOW) {
+ lpc18xx_gpio_pin_ic_isel(ic, d->hwirq, true);
+ lpc18xx_gpio_pin_ic_set(ic, d->hwirq,
+ LPC18XX_GPIO_PIN_IC_CIENF);
+ } else {
+ lpc18xx_gpio_pin_ic_isel(ic, d->hwirq, false);
+ }
+
+ raw_spin_unlock(&ic->lock);
+
+ return 0;
+}
+
+static struct irq_chip lpc18xx_gpio_pin_ic = {
+ .name = "LPC18xx GPIO pin",
+ .irq_mask = lpc18xx_gpio_pin_ic_mask,
+ .irq_unmask = lpc18xx_gpio_pin_ic_unmask,
+ .irq_eoi = lpc18xx_gpio_pin_ic_eoi,
+ .irq_set_type = lpc18xx_gpio_pin_ic_set_type,
+ .irq_retrigger = irq_chip_retrigger_hierarchy,
+ .flags = IRQCHIP_SET_TYPE_MASKED,
+};
+
+static int lpc18xx_gpio_pin_ic_domain_alloc(struct irq_domain *domain,
+ unsigned int virq,
+ unsigned int nr_irqs, void *data)
+{
+ struct irq_fwspec parent_fwspec, *fwspec = data;
+ struct lpc18xx_gpio_pin_ic *ic = domain->host_data;
+ irq_hw_number_t hwirq;
+ int ret;
+
+ if (nr_irqs != 1)
+ return -EINVAL;
+
+ hwirq = fwspec->param[0];
+ if (hwirq >= NR_LPC18XX_GPIO_PIN_IC_IRQS)
+ return -EINVAL;
+
+ /*
+ * All LPC18xx/LPC43xx GPIO pin hardware interrupts are translated
+ * into edge interrupts 32...39 on parent Cortex-M3/M4 NVIC
+ */
+ parent_fwspec.fwnode = domain->parent->fwnode;
+ parent_fwspec.param_count = 1;
+ parent_fwspec.param[0] = hwirq + 32;
+
+ ret = irq_domain_alloc_irqs_parent(domain, virq, 1, &parent_fwspec);
+ if (ret < 0) {
+ pr_err("failed to allocate parent irq %u: %d\n",
+ parent_fwspec.param[0], ret);
+ return ret;
+ }
+
+ return irq_domain_set_hwirq_and_chip(domain, virq, hwirq,
+ &lpc18xx_gpio_pin_ic, ic);
+}
+
+static const struct irq_domain_ops lpc18xx_gpio_pin_ic_domain_ops = {
+ .alloc = lpc18xx_gpio_pin_ic_domain_alloc,
+ .xlate = irq_domain_xlate_twocell,
+ .free = irq_domain_free_irqs_common,
+};
+
+static int lpc18xx_gpio_pin_ic_probe(struct lpc18xx_gpio_chip *gc)
+{
+ struct device *dev = gc->gpio.parent;
+ struct irq_domain *parent_domain;
+ struct device_node *parent_node;
+ struct lpc18xx_gpio_pin_ic *ic;
+ struct resource res;
+ int ret, index;
+
+ parent_node = of_irq_find_parent(dev->of_node);
+ if (!parent_node)
+ return -ENXIO;
+
+ parent_domain = irq_find_host(parent_node);
+ of_node_put(parent_node);
+ if (!parent_domain)
+ return -ENXIO;
+
+ ic = devm_kzalloc(dev, sizeof(*ic), GFP_KERNEL);
+ if (!ic)
+ return -ENOMEM;
+
+ index = of_property_match_string(dev->of_node, "reg-names",
+ "gpio-pin-ic");
+ if (index < 0) {
+ ret = -ENODEV;
+ goto free_ic;
+ }
+
+ ret = of_address_to_resource(dev->of_node, index, &res);
+ if (ret < 0)
+ goto free_ic;
+
+ ic->base = devm_ioremap_resource(dev, &res);
+ if (IS_ERR(ic->base)) {
+ ret = PTR_ERR(ic->base);
+ goto free_ic;
+ }
+
+ raw_spin_lock_init(&ic->lock);
+
+ ic->domain = irq_domain_add_hierarchy(parent_domain, 0,
+ NR_LPC18XX_GPIO_PIN_IC_IRQS,
+ dev->of_node,
+ &lpc18xx_gpio_pin_ic_domain_ops,
+ ic);
+ if (!ic->domain) {
+ pr_err("unable to add irq domain\n");
+ ret = -ENODEV;
+ goto free_iomap;
+ }
+
+ gc->pin_ic = ic;
+
+ return 0;
+
+free_iomap:
+ devm_iounmap(dev, ic->base);
+free_ic:
+ devm_kfree(dev, ic);
+
+ return ret;
+}
+
static void lpc18xx_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
{
struct lpc18xx_gpio_chip *gc = gpiochip_get_data(chip);
@@ -91,8 +330,7 @@ static int lpc18xx_gpio_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct lpc18xx_gpio_chip *gc;
- struct resource *res;
- int ret;
+ int index, ret;
gc = devm_kzalloc(dev, sizeof(*gc), GFP_KERNEL);
if (!gc)
@@ -101,8 +339,22 @@ static int lpc18xx_gpio_probe(struct platform_device *pdev)
gc->gpio = lpc18xx_chip;
platform_set_drvdata(pdev, gc);
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- gc->base = devm_ioremap_resource(dev, res);
+ index = of_property_match_string(dev->of_node, "reg-names", "gpio");
+ if (index < 0) {
+ /* To support backward compatibility take the first resource */
+ struct resource *res;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ gc->base = devm_ioremap_resource(dev, res);
+ } else {
+ struct resource res;
+
+ ret = of_address_to_resource(dev->of_node, index, &res);
+ if (ret < 0)
+ return ret;
+
+ gc->base = devm_ioremap_resource(dev, &res);
+ }
if (IS_ERR(gc->base))
return PTR_ERR(gc->base);
@@ -129,6 +381,9 @@ static int lpc18xx_gpio_probe(struct platform_device *pdev)
return ret;
}
+ /* On error GPIO pin interrupt controller just won't be registered */
+ lpc18xx_gpio_pin_ic_probe(gc);
+
return 0;
}
@@ -136,6 +391,9 @@ static int lpc18xx_gpio_remove(struct platform_device *pdev)
{
struct lpc18xx_gpio_chip *gc = platform_get_drvdata(pdev);
+ if (gc->pin_ic)
+ irq_domain_remove(gc->pin_ic->domain);
+
clk_disable_unprepare(gc->clk);
return 0;
@@ -158,5 +416,6 @@ static struct platform_driver lpc18xx_gpio_driver = {
module_platform_driver(lpc18xx_gpio_driver);
MODULE_AUTHOR("Joachim Eastwood <manabian@xxxxxxxxx>");
+MODULE_AUTHOR("Vladimir Zapolskiy <vz@xxxxxxxxx>");
MODULE_DESCRIPTION("GPIO driver for LPC18xx/43xx");
MODULE_LICENSE("GPL v2");
--
2.17.1
