Atheros AR5312 SoC have a builtin GPIO controller, which could be accessed
via memory mapped registers. This patch adds new driver for them.
Signed-off-by: Sergey Ryazanov <ryazanov.s.a@xxxxxxxxx>
Cc: Linus Walleij <linus.walleij@xxxxxxxxxx>
Cc: Alexandre Courbot <gnurou@xxxxxxxxx>
Cc: linux-gpio@xxxxxxxxxxxxxxx
---
Changes since RFC:
- move device registration to separate patch
drivers/gpio/Kconfig | 7 +++
drivers/gpio/Makefile | 1 +
drivers/gpio/gpio-ar5312.c | 121 +++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 129 insertions(+)
create mode 100644 drivers/gpio/gpio-ar5312.c
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 9de1515..7ce411b 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -112,6 +112,13 @@ config GPIO_MAX730X
comment "Memory mapped GPIO drivers:"
+config GPIO_AR5312
+ bool "AR5312 SoC GPIO support"
+ default y if SOC_AR5312
+ depends on SOC_AR5312
+ help
+ Say yes here to enable GPIO support for Atheros AR5312/AR2312+ SoCs.
+
config GPIO_CLPS711X
tristate "CLPS711X GPIO support"
depends on ARCH_CLPS711X || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 5d024e3..fae00f4 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -17,6 +17,7 @@ obj-$(CONFIG_GPIO_ADNP) += gpio-adnp.o
obj-$(CONFIG_GPIO_ADP5520) += gpio-adp5520.o
obj-$(CONFIG_GPIO_ADP5588) += gpio-adp5588.o
obj-$(CONFIG_GPIO_AMD8111) += gpio-amd8111.o
+obj-$(CONFIG_GPIO_AR5312) += gpio-ar5312.o
obj-$(CONFIG_GPIO_ARIZONA) += gpio-arizona.o
obj-$(CONFIG_GPIO_BCM_KONA) += gpio-bcm-kona.o
obj-$(CONFIG_GPIO_BT8XX) += gpio-bt8xx.o
diff --git a/drivers/gpio/gpio-ar5312.c b/drivers/gpio/gpio-ar5312.c
new file mode 100644
index 0000000..27adb61
--- /dev/null
+++ b/drivers/gpio/gpio-ar5312.c
@@ -0,0 +1,121 @@
+/*
+ * 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@xxxxxxxxxxx>
+ * Copyright (C) 2006-2009 Felix Fietkau <nbd@xxxxxxxxxxx>
+ * Copyright (C) 2012 Alexandros C. Couloumbis <alex@xxxxxxx>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/gpio.h>
+
+#define DRIVER_NAME "ar5312-gpio"
+
+#define AR5312_GPIO_DO 0x00 /* output register */
+#define AR5312_GPIO_DI 0x04 /* intput register */
+#define AR5312_GPIO_CR 0x08 /* control register */
+
+#define AR5312_GPIO_CR_M(x) (1 << (x)) /* mask for i/o */
+#define AR5312_GPIO_CR_O(x) (0 << (x)) /* mask for output */
+#define AR5312_GPIO_CR_I(x) (1 << (x)) /* mask for input */
+#define AR5312_GPIO_CR_INT(x) (1 << ((x)+8)) /* mask for interrupt */
+#define AR5312_GPIO_CR_UART(x) (1 << ((x)+16)) /* uart multiplex */
+
+#define AR5312_GPIO_NUM 8
+
+static void __iomem *ar5312_mem;
+
+static inline u32 ar5312_gpio_reg_read(unsigned reg)
+{
+ return __raw_readl(ar5312_mem + reg);
+}
+
+static inline void ar5312_gpio_reg_write(unsigned reg, u32 val)
+{
+ __raw_writel(val, ar5312_mem + reg);
+}
+
+static inline void ar5312_gpio_reg_mask(unsigned reg, u32 mask, u32 val)
+{
+ ar5312_gpio_reg_write(reg, (ar5312_gpio_reg_read(reg) & ~mask) | val);
+}
+
+static int ar5312_gpio_get_val(struct gpio_chip *chip, unsigned gpio)
+{
+ return (ar5312_gpio_reg_read(AR5312_GPIO_DI) >> gpio) & 1;
+}
+
+static void ar5312_gpio_set_val(struct gpio_chip *chip, unsigned gpio, int val)
+{
+ u32 reg = ar5312_gpio_reg_read(AR5312_GPIO_DO);
+
+ reg = val ? reg | (1 << gpio) : reg & ~(1 << gpio);
+ ar5312_gpio_reg_write(AR5312_GPIO_DO, reg);
+}
+
+static int ar5312_gpio_dir_in(struct gpio_chip *chip, unsigned gpio)
+{
+ ar5312_gpio_reg_mask(AR5312_GPIO_CR, 0, 1 << gpio);
+ return 0;
+}
+
+static int ar5312_gpio_dir_out(struct gpio_chip *chip, unsigned gpio, int val)
+{
+ ar5312_gpio_reg_mask(AR5312_GPIO_CR, 1 << gpio, 0);
+ ar5312_gpio_set_val(chip, gpio, val);
+ return 0;
+}
+
+static struct gpio_chip ar5312_gpio_chip = {
+ .label = DRIVER_NAME,
+ .direction_input = ar5312_gpio_dir_in,
+ .direction_output = ar5312_gpio_dir_out,
+ .set = ar5312_gpio_set_val,
+ .get = ar5312_gpio_get_val,
+ .base = 0,
+ .ngpio = AR5312_GPIO_NUM,
+};
+
+static int ar5312_gpio_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ int ret;
+
+ if (ar5312_mem)
+ return -EBUSY;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ ar5312_mem = devm_ioremap_resource(dev, res);
+ if (IS_ERR(ar5312_mem))
+ return PTR_ERR(ar5312_mem);
+
+ ar5312_gpio_chip.dev = dev;
+ ret = gpiochip_add(&ar5312_gpio_chip);
+ if (ret) {
+ dev_err(dev, "failed to add gpiochip\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static struct platform_driver ar5312_gpio_driver = {
+ .probe = ar5312_gpio_probe,
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ }
+};
+
+static int __init ar5312_gpio_init(void)
+{
+ return platform_driver_register(&ar5312_gpio_driver);
+}
+subsys_initcall(ar5312_gpio_init);
--
1.8.5.5
