[PATCH 02/15] GPIO: port LoCoMo gpio support from old driver

[Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>]

Add gpiolib driver for gpio pins placed on the LoCoMo GA.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
---
 drivers/gpio/Kconfig       |   7 ++
 drivers/gpio/Makefile      |   1 +
 drivers/gpio/gpio-locomo.c | 228 +++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 236 insertions(+)
 create mode 100644 drivers/gpio/gpio-locomo.c

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index 0959ca9..11c03d4 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -457,6 +457,13 @@ config GPIO_TB10X
 	select GENERIC_IRQ_CHIP
 	select OF_GPIO
 
+config GPIO_LOCOMO
+	bool "Sharp LoCoMo GPIO support"
+	depends on MFD_LOCOMO
+	help
+	  Select this to support GPIO pins on Sharp LoCoMo Grid Array found
+	  in Sharp Zaurus collie and poodle models.
+
 comment "I2C GPIO expanders:"
 
 config GPIO_ARIZONA
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index e5d346c..ed73f63 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -39,6 +39,7 @@ obj-$(CONFIG_GPIO_JANZ_TTL)	+= gpio-janz-ttl.o
 obj-$(CONFIG_GPIO_KEMPLD)	+= gpio-kempld.o
 obj-$(CONFIG_ARCH_KS8695)	+= gpio-ks8695.o
 obj-$(CONFIG_GPIO_INTEL_MID)	+= gpio-intel-mid.o
+obj-$(CONFIG_GPIO_LOCOMO)	+= gpio-locomo.o
 obj-$(CONFIG_GPIO_LP3943)	+= gpio-lp3943.o
 obj-$(CONFIG_ARCH_LPC32XX)	+= gpio-lpc32xx.o
 obj-$(CONFIG_GPIO_LYNXPOINT)	+= gpio-lynxpoint.o
diff --git a/drivers/gpio/gpio-locomo.c b/drivers/gpio/gpio-locomo.c
new file mode 100644
index 0000000..3b54b07
--- /dev/null
+++ b/drivers/gpio/gpio-locomo.c
@@ -0,0 +1,228 @@
+/*
+ * Sharp LoCoMo support for GPIO
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This file contains all generic LoCoMo support.
+ *
+ * All initialization functions provided here are intended to be called
+ * from machine specific code with proper arguments when required.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/gpio.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/mfd/locomo.h>
+
+struct locomo_gpio {
+	void __iomem *regs;
+
+	spinlock_t lock;
+	struct gpio_chip gpio;
+
+	u16 rising_edge;
+	u16 falling_edge;
+
+	u16 save_gpo;
+	u16 save_gpe;
+};
+
+static int locomo_gpio_get(struct gpio_chip *chip,
+		unsigned offset)
+{
+	struct locomo_gpio *lg = container_of(chip, struct locomo_gpio, gpio);
+
+	return readw(lg->regs + LOCOMO_GPL) & (1 << offset);
+}
+
+static void __locomo_gpio_set(struct gpio_chip *chip,
+		unsigned offset, int value)
+{
+	struct locomo_gpio *lg = container_of(chip, struct locomo_gpio, gpio);
+	u16  r;
+
+	r = readw(lg->regs + LOCOMO_GPO);
+	if (value)
+		r |= 1 << offset;
+	else
+		r &= ~(1 << offset);
+	writew(r, lg->regs + LOCOMO_GPO);
+}
+
+static void locomo_gpio_set(struct gpio_chip *chip,
+		unsigned offset, int value)
+{
+	struct locomo_gpio *lg = container_of(chip, struct locomo_gpio, gpio);
+	unsigned long flags;
+
+	spin_lock_irqsave(&lg->lock, flags);
+
+	__locomo_gpio_set(chip, offset, value);
+
+	spin_unlock_irqrestore(&lg->lock, flags);
+}
+
+static int locomo_gpio_direction_input(struct gpio_chip *chip,
+			unsigned offset)
+{
+	struct locomo_gpio *lg = container_of(chip, struct locomo_gpio, gpio);
+	unsigned long flags;
+	u16 r;
+
+	spin_lock_irqsave(&lg->lock, flags);
+
+	r = readw(lg->regs + LOCOMO_GPD);
+	r |= (1 << offset);
+	writew(r, lg->regs + LOCOMO_GPD);
+
+	r = readw(lg->regs + LOCOMO_GPE);
+	r |= (1 << offset);
+	writew(r, lg->regs + LOCOMO_GPE);
+
+	spin_unlock_irqrestore(&lg->lock, flags);
+
+	return 0;
+}
+
+static int locomo_gpio_direction_output(struct gpio_chip *chip,
+			unsigned offset, int value)
+{
+	struct locomo_gpio *lg = container_of(chip, struct locomo_gpio, gpio);
+	unsigned long flags;
+	u16 r;
+
+	spin_lock_irqsave(&lg->lock, flags);
+
+	__locomo_gpio_set(chip, offset, value);
+
+	r = readw(lg->regs + LOCOMO_GPD);
+	r &= ~(1 << offset);
+	writew(r, lg->regs + LOCOMO_GPD);
+
+	r = readw(lg->regs + LOCOMO_GPE);
+	r &= ~(1 << offset);
+	writew(r, lg->regs + LOCOMO_GPE);
+
+	spin_unlock_irqrestore(&lg->lock, flags);
+
+	return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int locomo_gpio_suspend(struct device *dev)
+{
+	struct locomo_gpio *lg = dev_get_drvdata(dev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&lg->lock, flags);
+
+	lg->save_gpo = readw(lg->regs + LOCOMO_GPO);
+	writew(0x00, lg->regs + LOCOMO_GPO);
+
+	lg->save_gpo = readw(lg->regs + LOCOMO_GPE);
+	writew(0x00, lg->regs + LOCOMO_GPE);
+
+	spin_unlock_irqrestore(&lg->lock, flags);
+	return 0;
+}
+
+static int locomo_gpio_resume(struct device *dev)
+{
+	struct locomo_gpio *lg = dev_get_drvdata(dev);
+	unsigned long flags;
+
+	spin_lock_irqsave(&lg->lock, flags);
+
+	writew(lg->save_gpo, lg->regs + LOCOMO_GPO);
+
+	writew(lg->save_gpe, lg->regs + LOCOMO_GPE);
+
+	spin_unlock_irqrestore(&lg->lock, flags);
+	return 0;
+}
+static SIMPLE_DEV_PM_OPS(locomo_gpio_pm,
+		locomo_gpio_suspend, locomo_gpio_resume);
+#define LOCOMO_GPIO_PM	(&locomo_gpio_pm)
+#else
+#define LOCOMO_GPIO_PM	NULL
+#endif
+
+static int locomo_gpio_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+	struct locomo_gpio *lg;
+	int ret;
+	struct locomo_gpio_platform_data *pdata = dev_get_platdata(&pdev->dev);
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res)
+		return -ENODEV;
+
+	lg = devm_kzalloc(&pdev->dev, sizeof(struct locomo_gpio),
+			GFP_KERNEL);
+	if (!lg)
+		return -ENOMEM;
+
+	lg->regs = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(lg->regs))
+		return PTR_ERR(lg->regs);
+
+	spin_lock_init(&lg->lock);
+
+	platform_set_drvdata(pdev, lg);
+
+	writew(0, lg->regs + LOCOMO_GPO);
+	writew(0, lg->regs + LOCOMO_GPE);
+	writew(0, lg->regs + LOCOMO_GPD);
+	writew(0, lg->regs + LOCOMO_GIE);
+
+	lg->gpio.base = pdata ? pdata->gpio_base : -1;
+	lg->gpio.label = "locomo-gpio";
+	lg->gpio.ngpio = 16;
+	lg->gpio.set = locomo_gpio_set;
+	lg->gpio.get = locomo_gpio_get;
+	lg->gpio.direction_input = locomo_gpio_direction_input;
+	lg->gpio.direction_output = locomo_gpio_direction_output;
+
+	ret = gpiochip_add(&lg->gpio);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+static int locomo_gpio_remove(struct platform_device *pdev)
+{
+	struct locomo_gpio *lg = platform_get_drvdata(pdev);
+	int ret;
+
+	ret = gpiochip_remove(&lg->gpio);
+	if (ret) {
+		dev_err(&pdev->dev, "Can't remove gpio chip: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static struct platform_driver locomo_gpio_driver = {
+	.probe		= locomo_gpio_probe,
+	.remove		= locomo_gpio_remove,
+	.driver		= {
+		.name	= "locomo-gpio",
+		.owner	= THIS_MODULE,
+		.pm	= LOCOMO_GPIO_PM,
+	},
+};
+module_platform_driver(locomo_gpio_driver);
+
+MODULE_DESCRIPTION("Sharp LoCoMo GPIO driver");
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("John Lenz <lenz@cs.wisc.edu>");
+MODULE_ALIAS("platform:locomo-gpio");
-- 
2.1.1