[PATCH v5 5/9] ARM: at91/gpio: add irqdomain and DT support
Nicolas Ferre
nicolas.ferre at atmel.com
Mon Feb 13 09:43:05 EST 2012
Add "legacy" type of irqdomain to preserve old-style numbering
and allow smooth transition for both DT and non-DT cases.
Original idea and code by Jean-Christophe Plagniol-Villard.
Signed-off-by: Nicolas Ferre <nicolas.ferre at atmel.com>
Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj at jcrosoft.com>
---
v5: - merge irqdomain and device tree modifications
- use "legacy" type of irqdomain (call to irq_domain_add_legacy())
- use more explicit variable names
v4: - at91_gpio_setup_clk() returns an error code
v3: - Corrections proposed by Russell King:
- use of clk_prepare()/clk_unprepare()
- helper function to setup the clock for both DT/non DT init functions
v2: - no BUG_ON() anymore in case of an "interrupts" property missing
just stop configuring the gpio bank
- review error path in both of_at91_gpio_init_one() and
at91_gpio_init_one()
- use for_each_compatible_node() iterator instead of a homemade loop
.../devicetree/bindings/gpio/gpio_atmel.txt | 20 ++
arch/arm/boot/dts/at91sam9g20.dtsi | 30 +++
arch/arm/boot/dts/at91sam9g45.dtsi | 50 +++++
arch/arm/mach-at91/gpio.c | 233 ++++++++++++++++----
4 files changed, 287 insertions(+), 46 deletions(-)
create mode 100644 Documentation/devicetree/bindings/gpio/gpio_atmel.txt
diff --git a/Documentation/devicetree/bindings/gpio/gpio_atmel.txt b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt
new file mode 100644
index 0000000..a7bcaec
--- /dev/null
+++ b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt
@@ -0,0 +1,20 @@
+* Atmel GPIO controller (PIO)
+
+Required properties:
+- compatible: "atmel,at91rm9200-gpio"
+- reg: Should contain GPIO controller registers location and length
+- interrupts: Should be the port interrupt shared by all the pins.
+- #gpio-cells: Should be two. The first cell is the pin number and
+ the second cell is used to specify optional parameters (currently
+ unused).
+- gpio-controller: Marks the device node as a GPIO controller.
+
+Example:
+ pioA: gpio at fffff200 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff200 0x100>;
+ interrupts = <2 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ };
+
diff --git a/arch/arm/boot/dts/at91sam9g20.dtsi b/arch/arm/boot/dts/at91sam9g20.dtsi
index 9a0aee7..325989a 100644
--- a/arch/arm/boot/dts/at91sam9g20.dtsi
+++ b/arch/arm/boot/dts/at91sam9g20.dtsi
@@ -23,6 +23,9 @@
serial4 = &usart3;
serial5 = &usart4;
serial6 = &usart5;
+ gpio0 = &pioA;
+ gpio1 = &pioB;
+ gpio2 = &pioC;
};
cpus {
cpu at 0 {
@@ -54,6 +57,33 @@
reg = <0xfffff000 0x200>;
};
+ pioA: gpio at fffff400 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff400 0x100>;
+ interrupts = <2 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
+ pioB: gpio at fffff600 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff600 0x100>;
+ interrupts = <3 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
+ pioC: gpio at fffff800 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff800 0x100>;
+ interrupts = <4 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
dbgu: serial at fffff200 {
compatible = "atmel,at91sam9260-usart";
reg = <0xfffff200 0x200>;
diff --git a/arch/arm/boot/dts/at91sam9g45.dtsi b/arch/arm/boot/dts/at91sam9g45.dtsi
index 67f94d3..a9dbbb5 100644
--- a/arch/arm/boot/dts/at91sam9g45.dtsi
+++ b/arch/arm/boot/dts/at91sam9g45.dtsi
@@ -22,6 +22,11 @@
serial2 = &usart1;
serial3 = &usart2;
serial4 = &usart3;
+ gpio0 = &pioA;
+ gpio1 = &pioB;
+ gpio2 = &pioC;
+ gpio3 = &pioD;
+ gpio4 = &pioE;
};
cpus {
cpu at 0 {
@@ -59,6 +64,51 @@
interrupts = <21 4>;
};
+ pioA: gpio at fffff200 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff200 0x100>;
+ interrupts = <2 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
+ pioB: gpio at fffff400 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff400 0x100>;
+ interrupts = <3 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
+ pioC: gpio at fffff600 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff600 0x100>;
+ interrupts = <4 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
+ pioD: gpio at fffff800 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffff800 0x100>;
+ interrupts = <5 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
+ pioE: gpio at fffffa00 {
+ compatible = "atmel,at91rm9200-gpio";
+ reg = <0xfffffa00 0x100>;
+ interrupts = <5 4>;
+ #gpio-cells = <2>;
+ gpio-controller;
+ interrupt-controller;
+ };
+
dbgu: serial at ffffee00 {
compatible = "atmel,at91sam9260-usart";
reg = <0xffffee00 0x200>;
diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
index b762afc..89e683a 100644
--- a/arch/arm/mach-at91/gpio.c
+++ b/arch/arm/mach-at91/gpio.c
@@ -20,6 +20,9 @@
#include <linux/list.h>
#include <linux/module.h>
#include <linux/io.h>
+#include <linux/irqdomain.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <mach/hardware.h>
#include <mach/at91_pio.h>
@@ -30,8 +33,10 @@ struct at91_gpio_chip {
struct gpio_chip chip;
struct at91_gpio_chip *next; /* Bank sharing same clock */
int pioc_hwirq; /* PIO bank interrupt identifier on AIC */
+ int pioc_idx; /* PIO bank index */
void __iomem *regbase; /* PIO bank virtual address */
struct clk *clock; /* associated clock */
+ struct irq_domain *domain; /* associated irq domain */
};
#define to_at91_gpio_chip(c) container_of(c, struct at91_gpio_chip, chip)
@@ -273,9 +278,9 @@ static u32 backups[MAX_GPIO_BANKS];
static int gpio_irq_set_wake(struct irq_data *d, unsigned state)
{
- unsigned pin = irq_to_gpio(d->irq);
- unsigned mask = pin_to_mask(pin);
- unsigned bank = pin / 32;
+ struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
+ unsigned mask = 1 << d->hwirq;
+ unsigned bank = at91_gpio->pioc_idx;
if (unlikely(bank >= MAX_GPIO_BANKS))
return -EINVAL;
@@ -301,9 +306,10 @@ void at91_gpio_suspend(void)
__raw_writel(backups[i], pio + PIO_IDR);
__raw_writel(wakeups[i], pio + PIO_IER);
- if (!wakeups[i])
+ if (!wakeups[i]) {
+ clk_unprepare(gpio_chip[i].clock);
clk_disable(gpio_chip[i].clock);
- else {
+ } else {
#ifdef CONFIG_PM_DEBUG
printk(KERN_DEBUG "GPIO-%c may wake for %08x\n", 'A'+i, wakeups[i]);
#endif
@@ -318,8 +324,10 @@ void at91_gpio_resume(void)
for (i = 0; i < gpio_banks; i++) {
void __iomem *pio = gpio_chip[i].regbase;
- if (!wakeups[i])
- clk_enable(gpio_chip[i].clock);
+ if (!wakeups[i]) {
+ if (clk_prepare(gpio_chip[i].clock) == 0)
+ clk_enable(gpio_chip[i].clock);
+ }
__raw_writel(wakeups[i], pio + PIO_IDR);
__raw_writel(backups[i], pio + PIO_IER);
@@ -344,9 +352,9 @@ void at91_gpio_resume(void)
static void gpio_irq_mask(struct irq_data *d)
{
- unsigned pin = irq_to_gpio(d->irq);
- void __iomem *pio = pin_to_controller(pin);
- unsigned mask = pin_to_mask(pin);
+ struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
+ void __iomem *pio = at91_gpio->regbase;
+ unsigned mask = 1 << d->hwirq;
if (pio)
__raw_writel(mask, pio + PIO_IDR);
@@ -354,9 +362,9 @@ static void gpio_irq_mask(struct irq_data *d)
static void gpio_irq_unmask(struct irq_data *d)
{
- unsigned pin = irq_to_gpio(d->irq);
- void __iomem *pio = pin_to_controller(pin);
- unsigned mask = pin_to_mask(pin);
+ struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(d);
+ void __iomem *pio = at91_gpio->regbase;
+ unsigned mask = 1 << d->hwirq;
if (pio)
__raw_writel(mask, pio + PIO_IER);
@@ -384,7 +392,7 @@ static struct irq_chip gpio_irqchip = {
static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
{
- unsigned irq_pin;
+ unsigned virq;
struct irq_data *idata = irq_desc_get_irq_data(desc);
struct irq_chip *chip = irq_data_get_irq_chip(idata);
struct at91_gpio_chip *at91_gpio = irq_data_get_irq_chip_data(idata);
@@ -407,12 +415,12 @@ static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
continue;
}
- irq_pin = gpio_to_irq(at91_gpio->chip.base);
+ virq = gpio_to_irq(at91_gpio->chip.base);
while (isr) {
if (isr & 1)
- generic_handle_irq(irq_pin);
- irq_pin++;
+ generic_handle_irq(virq);
+ virq++;
isr >>= 1;
}
}
@@ -483,6 +491,26 @@ postcore_initcall(at91_gpio_debugfs_init);
/*--------------------------------------------------------------------------*/
/*
+ * irqdomain initialization: pile up irqdomains on top of AIC range
+ */
+static void __init at91_gpio_irqdomain(struct at91_gpio_chip *at91_gpio)
+{
+ int irq_base;
+
+ irq_base = irq_alloc_descs(-1, 0, at91_gpio->chip.ngpio, 0);
+ if (irq_base < 0)
+ panic("at91_gpio.%d: error %d: couldn't allocate IRQ numbers.\n",
+ at91_gpio->pioc_idx, irq_base);
+ at91_gpio->domain = irq_domain_add_legacy(at91_gpio->chip.of_node,
+ at91_gpio->chip.ngpio,
+ irq_base, 0,
+ &irq_domain_simple_ops, NULL);
+ if (!at91_gpio->domain)
+ panic("at91_gpio.%d: couldn't allocate irq domain.\n",
+ at91_gpio->pioc_idx);
+}
+
+/*
* This lock class tells lockdep that GPIO irqs are in a different
* category than their parents, so it won't report false recursion.
*/
@@ -493,28 +521,35 @@ static struct lock_class_key gpio_lock_class;
*/
void __init at91_gpio_irq_setup(void)
{
- unsigned pioc, irq = gpio_to_irq(0);
+ unsigned pioc;
+ int gpio_irqnbr = 0;
struct at91_gpio_chip *this, *prev;
for (pioc = 0, this = gpio_chip, prev = NULL;
pioc++ < gpio_banks;
prev = this, this++) {
unsigned pioc_hwirq = this->pioc_hwirq;
- unsigned i;
+ int offset;
__raw_writel(~0, this->regbase + PIO_IDR);
- for (i = 0, irq = gpio_to_irq(this->chip.base); i < 32;
- i++, irq++) {
- irq_set_lockdep_class(irq, &gpio_lock_class);
+ /* setup irq domain for this GPIO controller */
+ at91_gpio_irqdomain(this);
+
+ for (offset = 0; offset < this->chip.ngpio; offset++) {
+ unsigned int virq = irq_find_mapping(this->domain, offset);
+ irq_set_lockdep_class(virq, &gpio_lock_class);
/*
* Can use the "simple" and not "edge" handler since it's
* shorter, and the AIC handles interrupts sanely.
*/
- irq_set_chip_and_handler(irq, &gpio_irqchip,
+ irq_set_chip_and_handler(virq, &gpio_irqchip,
handle_simple_irq);
- set_irq_flags(irq, IRQF_VALID);
+ set_irq_flags(virq, IRQF_VALID);
+ irq_set_chip_data(virq, this);
+
+ gpio_irqnbr++;
}
/* The toplevel handler handles one bank of GPIOs, except
@@ -527,7 +562,7 @@ void __init at91_gpio_irq_setup(void)
irq_set_chip_data(pioc_hwirq, this);
irq_set_chained_handler(pioc_hwirq, gpio_irq_handler);
}
- pr_info("AT91: %d gpio irqs in %d banks\n", irq - gpio_to_irq(0), gpio_banks);
+ pr_info("AT91: %d gpio irqs in %d banks\n", gpio_irqnbr, gpio_banks);
}
/* gpiolib support */
@@ -600,39 +635,145 @@ static void at91_gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
}
}
+static int __init at91_gpio_setup_clk(int idx)
+{
+ struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
+
+ /* retreive PIO controller's clock */
+ at91_gpio->clock = clk_get_sys(NULL, at91_gpio->chip.label);
+ if (IS_ERR(at91_gpio->clock)) {
+ pr_err("at91_gpio.%d, failed to get clock, ignoring.\n", idx);
+ goto err;
+ }
+
+ if (clk_prepare(at91_gpio->clock))
+ goto clk_prep_err;
+
+ /* enable PIO controller's clock */
+ if (clk_enable(at91_gpio->clock)) {
+ pr_err("at91_gpio.%d, failed to enable clock, ignoring.\n", idx);
+ goto clk_err;
+ }
+
+ return 0;
+
+clk_err:
+ clk_unprepare(at91_gpio->clock);
+clk_prep_err:
+ clk_put(at91_gpio->clock);
+err:
+ return -EINVAL;
+}
+
+#ifdef CONFIG_OF_GPIO
+static void __init of_at91_gpio_init_one(struct device_node *np)
+{
+ int alias_idx;
+ struct at91_gpio_chip *at91_gpio;
+
+ if (!np)
+ return;
+
+ alias_idx = of_alias_get_id(np, "gpio");
+ if (alias_idx >= MAX_GPIO_BANKS) {
+ pr_err("at91_gpio, failed alias idx(%d) > MAX_GPIO_BANKS(%d), ignoring.\n",
+ alias_idx, MAX_GPIO_BANKS);
+ return;
+ }
+
+ at91_gpio = &gpio_chip[alias_idx];
+ at91_gpio->chip.base = alias_idx * at91_gpio->chip.ngpio;
+
+ at91_gpio->regbase = of_iomap(np, 0);
+ if (!at91_gpio->regbase) {
+ pr_err("at91_gpio.%d, failed to map registers, ignoring.\n",
+ alias_idx);
+ return;
+ }
+
+ /* Get the interrupts property */
+ if (of_property_read_u32(np, "interrupts", &at91_gpio->pioc_hwirq)) {
+ pr_err("at91_gpio.%d, failed to get interrupts property, ignoring.\n",
+ alias_idx);
+ goto ioremap_err;
+ }
+
+ /* Setup clock */
+ if (at91_gpio_setup_clk(alias_idx))
+ goto ioremap_err;
+
+ at91_gpio->chip.of_node = np;
+ gpio_banks = max(gpio_banks, alias_idx + 1);
+ at91_gpio->pioc_idx = alias_idx;
+ return;
+
+ioremap_err:
+ iounmap(at91_gpio->regbase);
+}
+
+static int __init of_at91_gpio_init(void)
+{
+ struct device_node *np = NULL;
+
+ /*
+ * This isn't ideal, but it gets things hooked up until this
+ * driver is converted into a platform_device
+ */
+ for_each_compatible_node(np, NULL, "atmel,at91rm9200-gpio")
+ of_at91_gpio_init_one(np);
+
+ return gpio_banks > 0 ? 0 : -EINVAL;
+}
+#else
+static int __init of_at91_gpio_init(void)
+{
+ return -EINVAL;
+}
+#endif
+
+static void __init at91_gpio_init_one(int idx, u32 regbase, int pioc_hwirq)
+{
+ struct at91_gpio_chip *at91_gpio = &gpio_chip[idx];
+
+ at91_gpio->chip.base = idx * at91_gpio->chip.ngpio;
+ at91_gpio->pioc_hwirq = pioc_hwirq;
+ at91_gpio->pioc_idx = idx;
+
+ at91_gpio->regbase = ioremap(regbase, 512);
+ if (!at91_gpio->regbase) {
+ pr_err("at91_gpio.%d, failed to map registers, ignoring.\n", idx);
+ return;
+ }
+
+ if (at91_gpio_setup_clk(idx))
+ goto ioremap_err;
+
+ gpio_banks = max(gpio_banks, idx + 1);
+ return;
+
+ioremap_err:
+ iounmap(at91_gpio->regbase);
+}
+
/*
* Called from the processor-specific init to enable GPIO pin support.
*/
void __init at91_gpio_init(struct at91_gpio_bank *data, int nr_banks)
{
- unsigned i;
+ unsigned i;
struct at91_gpio_chip *at91_gpio, *last = NULL;
BUG_ON(nr_banks > MAX_GPIO_BANKS);
- gpio_banks = nr_banks;
+ if (of_at91_gpio_init() < 0) {
+ /* No GPIO controller found in device tree */
+ for (i = 0; i < nr_banks; i++)
+ at91_gpio_init_one(i, data[i].regbase, data[i].id);
+ }
- for (i = 0; i < nr_banks; i++) {
+ for (i = 0; i < gpio_banks; i++) {
at91_gpio = &gpio_chip[i];
- at91_gpio->pioc_hwirq = data[i].pioc_hwirq;
- at91_gpio->chip.base = i * 32;
-
- at91_gpio->regbase = ioremap(data[i].regbase, 512);
- if (!at91_gpio->regbase) {
- pr_err("at91_gpio.%d, failed to map registers, ignoring.\n", i);
- continue;
- }
-
- at91_gpio->clock = clk_get_sys(NULL, at91_gpio->chip.label);
- if (!at91_gpio->clock) {
- pr_err("at91_gpio.%d, failed to get clock, ignoring.\n", i);
- continue;
- }
-
- /* enable PIO controller's clock */
- clk_enable(at91_gpio->clock);
-
/*
* GPIO controller are grouped on some SoC:
* PIOC, PIOD and PIOE can share the same IRQ line
--
1.7.9
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