gpio: msm: Add device tree and irqdomain support for gpio-msm-v2

This cleans up the gpio-msm-v2 driver of all the global define usage.
The number of gpios are now defined in the device tree. This enables
adding irqdomain support as well.

Signed-off-by: Rohit Vaswani <rvaswani@codeaurora.org>
Acked-by: Grant Likely <grant.likely@linaro.org>
Signed-off-by: David Brown <davidb@codeaurora.org>

2 files changed, 114 insertions, 78 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 87d567089f13..6d61a12b68ff 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -165,7 +165,7 @@ config GPIO_MSM_V1
 
 config GPIO_MSM_V2
 	tristate "Qualcomm MSM GPIO v2"
-	depends on GPIOLIB && ARCH_MSM
+	depends on GPIOLIB && OF && ARCH_MSM
 	help
 	  Say yes here to support the GPIO interface on ARM v7 based
 	  Qualcomm MSM chips.  Most of the pins on the MSM can be
diff --git a/drivers/gpio/gpio-msm-v2.c b/drivers/gpio/gpio-msm-v2.c
index 75cc8215f15b..f4491a497cc8 100644
--- a/drivers/gpio/gpio-msm-v2.c
+++ b/drivers/gpio/gpio-msm-v2.c
@@ -19,17 +19,21 @@
 
 #include <linux/bitmap.h>
 #include <linux/bitops.h>
+#include <linux/err.h>
 #include <linux/gpio.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
 #include <linux/irqchip/chained_irq.h>
 #include <linux/irq.h>
+#include <linux/irqdomain.h>
 #include <linux/module.h>
+#include <linux/of_address.h>
 #include <linux/platform_device.h>
 #include <linux/spinlock.h>
+#include <linux/slab.h>
 
-#include <mach/msm_iomap.h>
+#define MAX_NR_GPIO 300
 
 /* Bits of interest in the GPIO_IN_OUT register.
  */
@@ -76,13 +80,6 @@ enum {
 	TARGET_PROC_NONE     = 7,
 };
 
-
-#define GPIO_INTR_CFG_SU(gpio)    (MSM_TLMM_BASE + 0x0400 + (0x04 * (gpio)))
-#define GPIO_CONFIG(gpio)         (MSM_TLMM_BASE + 0x1000 + (0x10 * (gpio)))
-#define GPIO_IN_OUT(gpio)         (MSM_TLMM_BASE + 0x1004 + (0x10 * (gpio)))
-#define GPIO_INTR_CFG(gpio)       (MSM_TLMM_BASE + 0x1008 + (0x10 * (gpio)))
-#define GPIO_INTR_STATUS(gpio)    (MSM_TLMM_BASE + 0x100c + (0x10 * (gpio)))
-
 /**
  * struct msm_gpio_dev: the MSM8660 SoC GPIO device structure
  *
@@ -101,11 +98,27 @@ enum {
  */
 struct msm_gpio_dev {
 	struct gpio_chip gpio_chip;
-	DECLARE_BITMAP(enabled_irqs, NR_GPIO_IRQS);
-	DECLARE_BITMAP(wake_irqs, NR_GPIO_IRQS);
-	DECLARE_BITMAP(dual_edge_irqs, NR_GPIO_IRQS);
+	DECLARE_BITMAP(enabled_irqs, MAX_NR_GPIO);
+	DECLARE_BITMAP(wake_irqs, MAX_NR_GPIO);
+	DECLARE_BITMAP(dual_edge_irqs, MAX_NR_GPIO);
+	struct irq_domain *domain;
+	unsigned int summary_irq;
+	void __iomem *msm_tlmm_base;
 };
 
+struct msm_gpio_dev msm_gpio;
+
+#define GPIO_INTR_CFG_SU(gpio)    (msm_gpio.msm_tlmm_base + 0x0400 + \
+								(0x04 * (gpio)))
+#define GPIO_CONFIG(gpio)         (msm_gpio.msm_tlmm_base + 0x1000 + \
+								(0x10 * (gpio)))
+#define GPIO_IN_OUT(gpio)         (msm_gpio.msm_tlmm_base + 0x1004 + \
+								(0x10 * (gpio)))
+#define GPIO_INTR_CFG(gpio)       (msm_gpio.msm_tlmm_base + 0x1008 + \
+								(0x10 * (gpio)))
+#define GPIO_INTR_STATUS(gpio)    (msm_gpio.msm_tlmm_base + 0x100c + \
+								(0x10 * (gpio)))
+
 static DEFINE_SPINLOCK(tlmm_lock);
 
 static inline struct msm_gpio_dev *to_msm_gpio_dev(struct gpio_chip *chip)
@@ -168,27 +181,19 @@ static void msm_gpio_free(struct gpio_chip *chip, unsigned offset)
 
 static int msm_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 {
-	return MSM_GPIO_TO_INT(chip->base + offset);
+	struct msm_gpio_dev *g_dev = to_msm_gpio_dev(chip);
+	struct irq_domain *domain = g_dev->domain;
+
+	return irq_create_mapping(domain, offset);
 }
 
 static inline int msm_irq_to_gpio(struct gpio_chip *chip, unsigned irq)
 {
-	return irq - MSM_GPIO_TO_INT(chip->base);
+	struct irq_data *irq_data = irq_get_irq_data(irq);
+
+	return irq_data->hwirq;
 }
 
-static struct msm_gpio_dev msm_gpio = {
-	.gpio_chip = {
-		.base             = 0,
-		.ngpio            = NR_GPIO_IRQS,
-		.direction_input  = msm_gpio_direction_input,
-		.direction_output = msm_gpio_direction_output,
-		.get              = msm_gpio_get,
-		.set              = msm_gpio_set,
-		.to_irq           = msm_gpio_to_irq,
-		.request          = msm_gpio_request,
-		.free             = msm_gpio_free,
-	},
-};
 
 /* For dual-edge interrupts in software, since the hardware has no
  * such support:
@@ -226,9 +231,9 @@ static void msm_gpio_update_dual_edge_pos(unsigned gpio)
 		if (intstat || val == val2)
 			return;
 	} while (loop_limit-- > 0);
-	pr_err("dual-edge irq failed to stabilize, "
+	pr_err("%s: dual-edge irq failed to stabilize, "
 	       "interrupts dropped. %#08x != %#08x\n",
-	       val, val2);
+	       __func__, val, val2);
 }
 
 static void msm_gpio_irq_ack(struct irq_data *d)
@@ -315,10 +320,10 @@ static void msm_summary_irq_handler(unsigned int irq, struct irq_desc *desc)
 
 	chained_irq_enter(chip, desc);
 
-	for_each_set_bit(i, msm_gpio.enabled_irqs, NR_GPIO_IRQS) {
+	for_each_set_bit(i, msm_gpio.enabled_irqs, MAX_NR_GPIO) {
 		if (readl(GPIO_INTR_STATUS(i)) & BIT(INTR_STATUS))
-			generic_handle_irq(msm_gpio_to_irq(&msm_gpio.gpio_chip,
-							   i));
+			generic_handle_irq(irq_find_mapping(msm_gpio.domain,
+								i));
 	}
 
 	chained_irq_exit(chip, desc);
@@ -329,13 +334,13 @@ static int msm_gpio_irq_set_wake(struct irq_data *d, unsigned int on)
 	int gpio = msm_irq_to_gpio(&msm_gpio.gpio_chip, d->irq);
 
 	if (on) {
-		if (bitmap_empty(msm_gpio.wake_irqs, NR_GPIO_IRQS))
-			irq_set_irq_wake(TLMM_SCSS_SUMMARY_IRQ, 1);
+		if (bitmap_empty(msm_gpio.wake_irqs, MAX_NR_GPIO))
+			irq_set_irq_wake(msm_gpio.summary_irq, 1);
 		set_bit(gpio, msm_gpio.wake_irqs);
 	} else {
 		clear_bit(gpio, msm_gpio.wake_irqs);
-		if (bitmap_empty(msm_gpio.wake_irqs, NR_GPIO_IRQS))
-			irq_set_irq_wake(TLMM_SCSS_SUMMARY_IRQ, 0);
+		if (bitmap_empty(msm_gpio.wake_irqs, MAX_NR_GPIO))
+			irq_set_irq_wake(msm_gpio.summary_irq, 0);
 	}
 
 	return 0;
@@ -350,30 +355,86 @@ static struct irq_chip msm_gpio_irq_chip = {
 	.irq_set_wake	= msm_gpio_irq_set_wake,
 };
 
-static int msm_gpio_probe(struct platform_device *dev)
+static struct lock_class_key msm_gpio_lock_class;
+
+static int msm_gpio_irq_domain_map(struct irq_domain *d, unsigned int irq,
+				   irq_hw_number_t hwirq)
+{
+	irq_set_lockdep_class(irq, &msm_gpio_lock_class);
+	irq_set_chip_and_handler(irq, &msm_gpio_irq_chip,
+			handle_level_irq);
+	set_irq_flags(irq, IRQF_VALID);
+
+	return 0;
+}
+
+static const struct irq_domain_ops msm_gpio_irq_domain_ops = {
+	.xlate = irq_domain_xlate_twocell,
+	.map = msm_gpio_irq_domain_map,
+};
+
+static int msm_gpio_probe(struct platform_device *pdev)
 {
-	int i, irq, ret;
+	int ret, ngpio;
+	struct resource *res;
+
+	if (!of_property_read_u32(pdev->dev.of_node, "ngpio", &ngpio)) {
+		dev_err(&pdev->dev, "%s: ngpio property missing\n", __func__);
+		return -EINVAL;
+	}
+
+	if (ngpio > MAX_NR_GPIO)
+		WARN(1, "ngpio exceeds the MAX_NR_GPIO. Increase MAX_NR_GPIO\n");
+
+	bitmap_zero(msm_gpio.enabled_irqs, MAX_NR_GPIO);
+	bitmap_zero(msm_gpio.wake_irqs, MAX_NR_GPIO);
+	bitmap_zero(msm_gpio.dual_edge_irqs, MAX_NR_GPIO);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	msm_gpio.msm_tlmm_base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(msm_gpio.msm_tlmm_base))
+		return PTR_ERR(msm_gpio.msm_tlmm_base);
+
+	msm_gpio.gpio_chip.ngpio = ngpio;
+	msm_gpio.gpio_chip.label = pdev->name;
+	msm_gpio.gpio_chip.dev = &pdev->dev;
+	msm_gpio.gpio_chip.base = 0;
+	msm_gpio.gpio_chip.direction_input = msm_gpio_direction_input;
+	msm_gpio.gpio_chip.direction_output = msm_gpio_direction_output;
+	msm_gpio.gpio_chip.get = msm_gpio_get;
+	msm_gpio.gpio_chip.set = msm_gpio_set;
+	msm_gpio.gpio_chip.to_irq = msm_gpio_to_irq;
+	msm_gpio.gpio_chip.request = msm_gpio_request;
+	msm_gpio.gpio_chip.free = msm_gpio_free;
 
-	bitmap_zero(msm_gpio.enabled_irqs, NR_GPIO_IRQS);
-	bitmap_zero(msm_gpio.wake_irqs, NR_GPIO_IRQS);
-	bitmap_zero(msm_gpio.dual_edge_irqs, NR_GPIO_IRQS);
-	msm_gpio.gpio_chip.label = dev->name;
 	ret = gpiochip_add(&msm_gpio.gpio_chip);
-	if (ret < 0)
+	if (ret < 0) {
+		dev_err(&pdev->dev, "gpiochip_add failed with error %d\n", ret);
 		return ret;
+	}
 
-	for (i = 0; i < msm_gpio.gpio_chip.ngpio; ++i) {
-		irq = msm_gpio_to_irq(&msm_gpio.gpio_chip, i);
-		irq_set_chip_and_handler(irq, &msm_gpio_irq_chip,
-					 handle_level_irq);
-		set_irq_flags(irq, IRQF_VALID);
+	msm_gpio.summary_irq = platform_get_irq(pdev, 0);
+	if (msm_gpio.summary_irq < 0) {
+		dev_err(&pdev->dev, "No Summary irq defined for msmgpio\n");
+		return msm_gpio.summary_irq;
 	}
 
-	irq_set_chained_handler(TLMM_SCSS_SUMMARY_IRQ,
-				msm_summary_irq_handler);
+	msm_gpio.domain = irq_domain_add_linear(pdev->dev.of_node, ngpio,
+						&msm_gpio_irq_domain_ops,
+						&msm_gpio);
+	if (!msm_gpio.domain)
+		return -ENODEV;
+
+	irq_set_chained_handler(msm_gpio.summary_irq, msm_summary_irq_handler);
+
 	return 0;
 }
 
+static struct of_device_id msm_gpio_of_match[] = {
+	{ .compatible = "qcom,msm-gpio", },
+	{ },
+};
+
 static int msm_gpio_remove(struct platform_device *dev)
 {
 	int ret = gpiochip_remove(&msm_gpio.gpio_chip);
@@ -381,7 +442,7 @@ static int msm_gpio_remove(struct platform_device *dev)
 	if (ret < 0)
 		return ret;
 
-	irq_set_handler(TLMM_SCSS_SUMMARY_IRQ, NULL);
+	irq_set_handler(msm_gpio.summary_irq, NULL);
 
 	return 0;
 }
@@ -392,36 +453,11 @@ static struct platform_driver msm_gpio_driver = {
 	.driver = {
 		.name = "msmgpio",
 		.owner = THIS_MODULE,
+		.of_match_table = msm_gpio_of_match,
 	},
 };
 
-static struct platform_device msm_device_gpio = {
-	.name = "msmgpio",
-	.id   = -1,
-};
-
-static int __init msm_gpio_init(void)
-{
-	int rc;
-
-	rc = platform_driver_register(&msm_gpio_driver);
-	if (!rc) {
-		rc = platform_device_register(&msm_device_gpio);
-		if (rc)
-			platform_driver_unregister(&msm_gpio_driver);
-	}
-
-	return rc;
-}
-
-static void __exit msm_gpio_exit(void)
-{
-	platform_device_unregister(&msm_device_gpio);
-	platform_driver_unregister(&msm_gpio_driver);
-}
-
-postcore_initcall(msm_gpio_init);
-module_exit(msm_gpio_exit);
+module_platform_driver(msm_gpio_driver)
 
 MODULE_AUTHOR("Gregory Bean <gbean@codeaurora.org>");
 MODULE_DESCRIPTION("Driver for Qualcomm MSM TLMMv2 SoC GPIOs");