openwrt/target/linux/ath25/patches-4.14/108-ar2315_gpio.patch

--- a/arch/mips/ath25/Kconfig
+++ b/arch/mips/ath25/Kconfig
@@ -8,6 +8,7 @@ config SOC_AR5312
 config SOC_AR2315
 	bool "Atheros AR2315+ SoC support"
 	depends on ATH25
+	select GPIO_AR2315
 	default y
 
 config PCI_AR2315
--- a/arch/mips/ath25/ar2315.c
+++ b/arch/mips/ath25/ar2315.c
@@ -21,6 +21,8 @@
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
 #include <linux/reboot.h>
+#include <linux/delay.h>
+#include <linux/gpio.h>
 #include <asm/bootinfo.h>
 #include <asm/reboot.h>
 #include <asm/time.h>
@@ -167,11 +169,42 @@ void __init ar2315_arch_init_irq(void)
 	ar2315_misc_irq_domain = domain;
 }
 
+static struct resource ar2315_gpio_res[] = {
+	{
+		.name = "ar2315-gpio",
+		.flags = IORESOURCE_MEM,
+		.start = AR2315_RST_BASE + AR2315_GPIO,
+		.end = AR2315_RST_BASE + AR2315_GPIO + 0x10 - 1,
+	},
+	{
+		.name = "ar2315-gpio",
+		.flags = IORESOURCE_IRQ,
+	},
+	{
+		.name = "ar2315-gpio-irq-base",
+		.flags = IORESOURCE_IRQ,
+		.start = AR231X_GPIO_IRQ_BASE,
+		.end = AR231X_GPIO_IRQ_BASE,
+	}
+};
+
+static struct platform_device ar2315_gpio = {
+	.id = -1,
+	.name = "ar2315-gpio",
+	.resource = ar2315_gpio_res,
+	.num_resources = ARRAY_SIZE(ar2315_gpio_res)
+};
+
 void __init ar2315_init_devices(void)
 {
 	/* Find board configuration */
 	ath25_find_config(AR2315_SPI_READ_BASE, AR2315_SPI_READ_SIZE);
 
+	ar2315_gpio_res[1].start = irq_create_mapping(ar2315_misc_irq_domain,
+						      AR2315_MISC_IRQ_GPIO);
+	ar2315_gpio_res[1].end = ar2315_gpio_res[1].start;
+	platform_device_register(&ar2315_gpio);
+
 	ath25_add_wmac(0, AR2315_WLAN0_BASE, AR2315_IRQ_WLAN0);
 }
 
@@ -187,8 +220,8 @@ static void ar2315_restart(char *command
 	/* Cold reset does not work on the AR2315/6, use the GPIO reset bits
 	 * a workaround. Give it some time to attempt a gpio based hardware
 	 * reset (atheros reference design workaround) */
-
-	/* TODO: implement the GPIO reset workaround */
+	gpio_request_one(AR2315_RESET_GPIO, GPIOF_OUT_INIT_LOW, "Reset");
+	mdelay(100);
 
 	/* Some boards (e.g. Senao EOC-2610) don't implement the reset logic
 	 * workaround. Attempt to jump to the mips reset location -
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -105,6 +105,13 @@ config GPIO_AMDPT
 	  driver for GPIO functionality on Promontory IOHub
 	  Require ACPI ASL code to enumerate as a platform device.
 
+config GPIO_AR2315
+	bool "AR2315 SoC GPIO support"
+	default y if SOC_AR2315
+	depends on SOC_AR2315
+	help
+	  Say yes here to enable GPIO support for Atheros AR2315+ SoCs.
+
 config GPIO_AR5312
 	bool "AR5312 SoC GPIO support"
 	default y if SOC_AR5312
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_GPIO_ALTERA)  	+= gpio-alte
 obj-$(CONFIG_GPIO_ALTERA_A10SR)	+= gpio-altera-a10sr.o
 obj-$(CONFIG_GPIO_AMD8111)	+= gpio-amd8111.o
 obj-$(CONFIG_GPIO_AMDPT)	+= gpio-amdpt.o
+obj-$(CONFIG_GPIO_AR2315)	+= gpio-ar2315.o
 obj-$(CONFIG_GPIO_AR5312)	+= gpio-ar5312.o
 obj-$(CONFIG_GPIO_ARIZONA)	+= gpio-arizona.o
 obj-$(CONFIG_GPIO_ATH79)	+= gpio-ath79.o
--- /dev/null
+++ b/drivers/gpio/gpio-ar2315.c
@@ -0,0 +1,233 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2003 Atheros Communications, Inc.,  All Rights Reserved.
+ * Copyright (C) 2006 FON Technology, SL.
+ * Copyright (C) 2006 Imre Kaloz <kaloz@openwrt.org>
+ * Copyright (C) 2006 Felix Fietkau <nbd@nbd.name>
+ * Copyright (C) 2012 Alexandros C. Couloumbis <alex@ozo.com>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+#include <linux/irq.h>
+
+#define DRIVER_NAME	"ar2315-gpio"
+
+#define AR2315_GPIO_DI			0x0000
+#define AR2315_GPIO_DO			0x0008
+#define AR2315_GPIO_DIR			0x0010
+#define AR2315_GPIO_INT			0x0018
+
+#define AR2315_GPIO_DIR_M(x)		(1 << (x))	/* mask for i/o */
+#define AR2315_GPIO_DIR_O(x)		(1 << (x))	/* output */
+#define AR2315_GPIO_DIR_I(x)		(0)		/* input */
+
+#define AR2315_GPIO_INT_NUM_M		0x3F		/* mask for GPIO num */
+#define AR2315_GPIO_INT_TRIG(x)		((x) << 6)	/* interrupt trigger */
+#define AR2315_GPIO_INT_TRIG_M		(0x3 << 6)	/* mask for int trig */
+
+#define AR2315_GPIO_INT_TRIG_OFF	0	/* Triggerring off */
+#define AR2315_GPIO_INT_TRIG_LOW	1	/* Low Level Triggered */
+#define AR2315_GPIO_INT_TRIG_HIGH	2	/* High Level Triggered */
+#define AR2315_GPIO_INT_TRIG_EDGE	3	/* Edge Triggered */
+
+#define AR2315_GPIO_NUM		22
+
+static u32 ar2315_gpio_intmask;
+static u32 ar2315_gpio_intval;
+static unsigned ar2315_gpio_irq_base;
+static void __iomem *ar2315_mem;
+
+static inline u32 ar2315_gpio_reg_read(unsigned reg)
+{
+	return __raw_readl(ar2315_mem + reg);
+}
+
+static inline void ar2315_gpio_reg_write(unsigned reg, u32 val)
+{
+	__raw_writel(val, ar2315_mem + reg);
+}
+
+static inline void ar2315_gpio_reg_mask(unsigned reg, u32 mask, u32 val)
+{
+	ar2315_gpio_reg_write(reg, (ar2315_gpio_reg_read(reg) & ~mask) | val);
+}
+
+static void ar2315_gpio_irq_handler(struct irq_desc *desc)
+{
+	u32 pend;
+	int bit = -1;
+
+	/* only do one gpio interrupt at a time */
+	pend = ar2315_gpio_reg_read(AR2315_GPIO_DI);
+	pend ^= ar2315_gpio_intval;
+	pend &= ar2315_gpio_intmask;
+
+	if (pend) {
+		bit = fls(pend) - 1;
+		pend &= ~(1 << bit);
+		ar2315_gpio_intval ^= (1 << bit);
+	}
+
+	/* Enable interrupt with edge detection */
+	if ((ar2315_gpio_reg_read(AR2315_GPIO_DIR) & AR2315_GPIO_DIR_M(bit)) !=
+	    AR2315_GPIO_DIR_I(bit))
+		return;
+
+	if (bit >= 0)
+		generic_handle_irq(ar2315_gpio_irq_base + bit);
+}
+
+static void ar2315_gpio_int_setup(unsigned gpio, int trig)
+{
+	u32 reg = ar2315_gpio_reg_read(AR2315_GPIO_INT);
+
+	reg &= ~(AR2315_GPIO_INT_NUM_M | AR2315_GPIO_INT_TRIG_M);
+	reg |= gpio | AR2315_GPIO_INT_TRIG(trig);
+	ar2315_gpio_reg_write(AR2315_GPIO_INT, reg);
+}
+
+static void ar2315_gpio_irq_unmask(struct irq_data *d)
+{
+	unsigned gpio = d->irq - ar2315_gpio_irq_base;
+	u32 dir = ar2315_gpio_reg_read(AR2315_GPIO_DIR);
+
+	/* Enable interrupt with edge detection */
+	if ((dir & AR2315_GPIO_DIR_M(gpio)) != AR2315_GPIO_DIR_I(gpio))
+		return;
+
+	ar2315_gpio_intmask |= (1 << gpio);
+	ar2315_gpio_int_setup(gpio, AR2315_GPIO_INT_TRIG_EDGE);
+}
+
+static void ar2315_gpio_irq_mask(struct irq_data *d)
+{
+	unsigned gpio = d->irq - ar2315_gpio_irq_base;
+
+	/* Disable interrupt */
+	ar2315_gpio_intmask &= ~(1 << gpio);
+	ar2315_gpio_int_setup(gpio, AR2315_GPIO_INT_TRIG_OFF);
+}
+
+static struct irq_chip ar2315_gpio_irq_chip = {
+	.name		= DRIVER_NAME,
+	.irq_unmask	= ar2315_gpio_irq_unmask,
+	.irq_mask	= ar2315_gpio_irq_mask,
+};
+
+static void ar2315_gpio_irq_init(unsigned irq)
+{
+	unsigned i;
+
+	ar2315_gpio_intval = ar2315_gpio_reg_read(AR2315_GPIO_DI);
+	for (i = 0; i < AR2315_GPIO_NUM; i++) {
+		unsigned _irq = ar2315_gpio_irq_base + i;
+
+		irq_set_chip_and_handler(_irq, &ar2315_gpio_irq_chip,
+					 handle_level_irq);
+	}
+	irq_set_chained_handler(irq, ar2315_gpio_irq_handler);
+}
+
+static int ar2315_gpio_get_val(struct gpio_chip *chip, unsigned gpio)
+{
+	return (ar2315_gpio_reg_read(AR2315_GPIO_DI) >> gpio) & 1;
+}
+
+static void ar2315_gpio_set_val(struct gpio_chip *chip, unsigned gpio, int val)
+{
+	u32 reg = ar2315_gpio_reg_read(AR2315_GPIO_DO);
+
+	reg = val ? reg | (1 << gpio) : reg & ~(1 << gpio);
+	ar2315_gpio_reg_write(AR2315_GPIO_DO, reg);
+}
+
+static int ar2315_gpio_dir_in(struct gpio_chip *chip, unsigned gpio)
+{
+	ar2315_gpio_reg_mask(AR2315_GPIO_DIR, 1 << gpio, 0);
+	return 0;
+}
+
+static int ar2315_gpio_dir_out(struct gpio_chip *chip, unsigned gpio, int val)
+{
+	ar2315_gpio_reg_mask(AR2315_GPIO_DIR, 0, 1 << gpio);
+	ar2315_gpio_set_val(chip, gpio, val);
+	return 0;
+}
+
+static int ar2315_gpio_to_irq(struct gpio_chip *chip, unsigned gpio)
+{
+	return ar2315_gpio_irq_base + gpio;
+}
+
+static struct gpio_chip ar2315_gpio_chip = {
+	.label			= DRIVER_NAME,
+	.direction_input	= ar2315_gpio_dir_in,
+	.direction_output	= ar2315_gpio_dir_out,
+	.set			= ar2315_gpio_set_val,
+	.get			= ar2315_gpio_get_val,
+	.to_irq			= ar2315_gpio_to_irq,
+	.base			= 0,
+	.ngpio			= AR2315_GPIO_NUM,
+};
+
+static int ar2315_gpio_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct resource *res;
+	unsigned irq;
+	int ret;
+
+	if (ar2315_mem)
+		return -EBUSY;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_IRQ,
+					   "ar2315-gpio-irq-base");
+	if (!res) {
+		dev_err(dev, "not found GPIO IRQ base\n");
+		return -ENXIO;
+	}
+	ar2315_gpio_irq_base = res->start;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_IRQ, DRIVER_NAME);
+	if (!res) {
+		dev_err(dev, "not found IRQ number\n");
+		return -ENXIO;
+	}
+	irq = res->start;
+
+	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, DRIVER_NAME);
+	ar2315_mem = devm_ioremap_resource(dev, res);
+	if (IS_ERR(ar2315_mem))
+		return PTR_ERR(ar2315_mem);
+
+	ar2315_gpio_chip.parent = dev;
+	ret = gpiochip_add(&ar2315_gpio_chip);
+	if (ret) {
+		dev_err(dev, "failed to add gpiochip\n");
+		return ret;
+	}
+
+	ar2315_gpio_irq_init(irq);
+
+	return 0;
+}
+
+static struct platform_driver ar2315_gpio_driver = {
+	.probe = ar2315_gpio_probe,
+	.driver = {
+		.name = DRIVER_NAME,
+		.owner = THIS_MODULE,
+	}
+};
+
+static int __init ar2315_gpio_init(void)
+{
+	return platform_driver_register(&ar2315_gpio_driver);
+}
+subsys_initcall(ar2315_gpio_init);
--- a/arch/mips/ath25/devices.h
+++ b/arch/mips/ath25/devices.h
@@ -4,6 +4,11 @@
 
 #include <linux/cpu.h>
 
+#define AR231X_GPIO_IRQ_BASE		0x30
+
+/* GPIO number for AR2315/16 reset issue workaround */
+#define AR2315_RESET_GPIO		5
+
 #define ATH25_REG_MS(_val, _field)	(((_val) & _field##_M) >> _field##_S)
 
 #define ATH25_IRQ_CPU_CLOCK	(MIPS_CPU_IRQ_BASE + 7)	/* C0_CAUSE: 0x8000 */
--- a/arch/mips/ath25/ar2315_regs.h
+++ b/arch/mips/ath25/ar2315_regs.h
@@ -315,6 +315,9 @@
 #define AR2315_MEM_CFG_BANKADDR_BITS_M	0x00000018
 #define AR2315_MEM_CFG_BANKADDR_BITS_S	3
 
+/* GPIO MMR base address */
+#define AR2315_GPIO			0x0088
+
 /*
  * Local Bus Interface Registers
  */