gpio: adp5588-gpio: new driver for ADP5588 GPIO expanders

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

3 files changed, 276 insertions, 0 deletions

diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index a019b49ecc9b..1f1d88ae68d6 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -172,6 +172,15 @@ config GPIO_ADP5520
           To compile this driver as a module, choose M here: the module will
           be called adp5520-gpio.
 
+config GPIO_ADP5588
+        tristate "ADP5588 I2C GPIO expander"
+        depends on I2C
+        help
+          This option enables support for 18 GPIOs found
+          on Analog Devices ADP5588 GPIO Expanders.
+          To compile this driver as a module, choose M here: the module will be
+          called adp5588-gpio.
+
 comment "PCI GPIO expanders:"
 
 config GPIO_CS5535
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 52fe4cf734c7..48687238edb1 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -5,6 +5,7 @@ ccflags-$(CONFIG_DEBUG_GPIO)	+= -DDEBUG
 obj-$(CONFIG_GPIOLIB)           += gpiolib.o
 
 obj-$(CONFIG_GPIO_ADP5520)      += adp5520-gpio.o
+obj-$(CONFIG_GPIO_ADP5588)      += adp5588-gpio.o
 obj-$(CONFIG_GPIO_LANGWELL)     += langwell_gpio.o
 obj-$(CONFIG_GPIO_MAX7301)      += max7301.o
 obj-$(CONFIG_GPIO_MAX732X)      += max732x.o
diff --git a/drivers/gpio/adp5588-gpio.c b/drivers/gpio/adp5588-gpio.c
new file mode 100644
index 000000000000..afc097a16b33
--- /dev/null
+++ b/drivers/gpio/adp5588-gpio.c
@@ -0,0 +1,266 @@
+/*
+ * GPIO Chip driver for Analog Devices
+ * ADP5588 I/O Expander and QWERTY Keypad Controller
+ *
+ * Copyright 2009 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+
+#include <linux/i2c/adp5588.h>
+
+#define DRV_NAME                "adp5588-gpio"
+#define MAXGPIO                 18
+#define ADP_BANK(offs)          ((offs) >> 3)
+#define ADP_BIT(offs)           (1u << ((offs) & 0x7))
+
+struct adp5588_gpio {
+        struct i2c_client *client;
+        struct gpio_chip gpio_chip;
+        struct mutex lock;      /* protect cached dir, dat_out */
+        unsigned gpio_start;
+        uint8_t dat_out[3];
+        uint8_t dir[3];
+};
+
+static int adp5588_gpio_read(struct i2c_client *client, u8 reg)
+{
+        int ret = i2c_smbus_read_byte_data(client, reg);
+
+        if (ret < 0)
+                dev_err(&client->dev, "Read Error\n");
+
+        return ret;
+}
+
+static int adp5588_gpio_write(struct i2c_client *client, u8 reg, u8 val)
+{
+        int ret = i2c_smbus_write_byte_data(client, reg, val);
+
+        if (ret < 0)
+                dev_err(&client->dev, "Write Error\n");
+
+        return ret;
+}
+
+static int adp5588_gpio_get_value(struct gpio_chip *chip, unsigned off)
+{
+        struct adp5588_gpio *dev =
+            container_of(chip, struct adp5588_gpio, gpio_chip);
+
+        return !!(adp5588_gpio_read(dev->client, GPIO_DAT_STAT1 + ADP_BANK(off))
+                  & ADP_BIT(off));
+}
+
+static void adp5588_gpio_set_value(struct gpio_chip *chip,
+                                   unsigned off, int val)
+{
+        unsigned bank, bit;
+        struct adp5588_gpio *dev =
+            container_of(chip, struct adp5588_gpio, gpio_chip);
+
+        bank = ADP_BANK(off);
+        bit = ADP_BIT(off);
+
+        mutex_lock(&dev->lock);
+        if (val)
+                dev->dat_out[bank] |= bit;
+        else
+                dev->dat_out[bank] &= ~bit;
+
+        adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
+                           dev->dat_out[bank]);
+        mutex_unlock(&dev->lock);
+}
+
+static int adp5588_gpio_direction_input(struct gpio_chip *chip, unsigned off)
+{
+        int ret;
+        unsigned bank;
+        struct adp5588_gpio *dev =
+            container_of(chip, struct adp5588_gpio, gpio_chip);
+
+        bank = ADP_BANK(off);
+
+        mutex_lock(&dev->lock);
+        dev->dir[bank] &= ~ADP_BIT(off);
+        ret = adp5588_gpio_write(dev->client, GPIO_DIR1 + bank, dev->dir[bank]);
+        mutex_unlock(&dev->lock);
+
+        return ret;
+}
+
+static int adp5588_gpio_direction_output(struct gpio_chip *chip,
+                                         unsigned off, int val)
+{
+        int ret;
+        unsigned bank, bit;
+        struct adp5588_gpio *dev =
+            container_of(chip, struct adp5588_gpio, gpio_chip);
+
+        bank = ADP_BANK(off);
+        bit = ADP_BIT(off);
+
+        mutex_lock(&dev->lock);
+        dev->dir[bank] |= bit;
+
+        if (val)
+                dev->dat_out[bank] |= bit;
+        else
+                dev->dat_out[bank] &= ~bit;
+
+        ret = adp5588_gpio_write(dev->client, GPIO_DAT_OUT1 + bank,
+                                 dev->dat_out[bank]);
+        ret |= adp5588_gpio_write(dev->client, GPIO_DIR1 + bank,
+                                 dev->dir[bank]);
+        mutex_unlock(&dev->lock);
+
+        return ret;
+}
+
+static int __devinit adp5588_gpio_probe(struct i2c_client *client,
+                                        const struct i2c_device_id *id)
+{
+        struct adp5588_gpio_platform_data *pdata = client->dev.platform_data;
+        struct adp5588_gpio *dev;
+        struct gpio_chip *gc;
+        int ret, i, revid;
+
+        if (pdata == NULL) {
+                dev_err(&client->dev, "missing platform data\n");
+                return -ENODEV;
+        }
+
+        if (!i2c_check_functionality(client->adapter,
+                                        I2C_FUNC_SMBUS_BYTE_DATA)) {
+                dev_err(&client->dev, "SMBUS Byte Data not Supported\n");
+                return -EIO;
+        }
+
+        dev = kzalloc(sizeof(*dev), GFP_KERNEL);
+        if (dev == NULL) {
+                dev_err(&client->dev, "failed to alloc memory\n");
+                return -ENOMEM;
+        }
+
+        dev->client = client;
+
+        gc = &dev->gpio_chip;
+        gc->direction_input = adp5588_gpio_direction_input;
+        gc->direction_output = adp5588_gpio_direction_output;
+        gc->get = adp5588_gpio_get_value;
+        gc->set = adp5588_gpio_set_value;
+        gc->can_sleep = 1;
+
+        gc->base = pdata->gpio_start;
+        gc->ngpio = MAXGPIO;
+        gc->label = client->name;
+        gc->owner = THIS_MODULE;
+
+        mutex_init(&dev->lock);
+
+
+        ret = adp5588_gpio_read(dev->client, DEV_ID);
+        if (ret < 0)
+                goto err;
+
+        revid = ret & ADP5588_DEVICE_ID_MASK;
+
+        for (i = 0, ret = 0; i <= ADP_BANK(MAXGPIO); i++) {
+                dev->dat_out[i] = adp5588_gpio_read(client, GPIO_DAT_OUT1 + i);
+                dev->dir[i] = adp5588_gpio_read(client, GPIO_DIR1 + i);
+                ret |= adp5588_gpio_write(client, KP_GPIO1 + i, 0);
+                ret |= adp5588_gpio_write(client, GPIO_PULL1 + i,
+                                (pdata->pullup_dis_mask >> (8 * i)) & 0xFF);
+
+                if (ret)
+                        goto err;
+        }
+
+        ret = gpiochip_add(&dev->gpio_chip);
+        if (ret)
+                goto err;
+
+        dev_info(&client->dev, "gpios %d..%d on a %s Rev. %d\n",
+                        gc->base, gc->base + gc->ngpio - 1,
+                        client->name, revid);
+
+        if (pdata->setup) {
+                ret = pdata->setup(client, gc->base, gc->ngpio, pdata->context);
+                if (ret < 0)
+                        dev_warn(&client->dev, "setup failed, %d\n", ret);
+        }
+
+        i2c_set_clientdata(client, dev);
+        return 0;
+
+err:
+        kfree(dev);
+        return ret;
+}
+
+static int __devexit adp5588_gpio_remove(struct i2c_client *client)
+{
+        struct adp5588_gpio_platform_data *pdata = client->dev.platform_data;
+        struct adp5588_gpio *dev = i2c_get_clientdata(client);
+        int ret;
+
+        if (pdata->teardown) {
+                ret = pdata->teardown(client,
+                                      dev->gpio_chip.base, dev->gpio_chip.ngpio,
+                                      pdata->context);
+                if (ret < 0) {
+                        dev_err(&client->dev, "teardown failed %d\n", ret);
+                        return ret;
+                }
+        }
+
+        ret = gpiochip_remove(&dev->gpio_chip);
+        if (ret) {
+                dev_err(&client->dev, "gpiochip_remove failed %d\n", ret);
+                return ret;
+        }
+
+        kfree(dev);
+        return 0;
+}
+
+static const struct i2c_device_id adp5588_gpio_id[] = {
+        {DRV_NAME, 0},
+        {}
+};
+
+MODULE_DEVICE_TABLE(i2c, adp5588_gpio_id);
+
+static struct i2c_driver adp5588_gpio_driver = {
+        .driver = {
+                   .name = DRV_NAME,
+                   },
+        .probe = adp5588_gpio_probe,
+        .remove = __devexit_p(adp5588_gpio_remove),
+        .id_table = adp5588_gpio_id,
+};
+
+static int __init adp5588_gpio_init(void)
+{
+        return i2c_add_driver(&adp5588_gpio_driver);
+}
+
+module_init(adp5588_gpio_init);
+
+static void __exit adp5588_gpio_exit(void)
+{
+        i2c_del_driver(&adp5588_gpio_driver);
+}
+
+module_exit(adp5588_gpio_exit);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("GPIO ADP5588 Driver");
+MODULE_LICENSE("GPL");