gpio: rename pca9539 driver

First part of an extension to let the pca9539 driver support more chips,
starting with pca9534, pca9535, pca9536, pca9537, and pca9538.

This renames the files and modifies the Makefile.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de>
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 271 insertions, 0 deletions

diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
new file mode 100644
index 000000000000..7fae4e500dfd
--- /dev/null
+++ b/drivers/gpio/pca953x.c
@@ -0,0 +1,271 @@
+/*
+ *  pca9539.c - 16-bit I/O port with interrupt and reset
+ *
+ *  Copyright (C) 2005 Ben Gardner <bgardner@wabtec.com>
+ *  Copyright (C) 2007 Marvell International Ltd.
+ *
+ *  Derived from drivers/i2c/chips/pca9539.c
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; version 2 of the License.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/i2c/pca953x.h>
+
+#include <asm/gpio.h>
+
+
+#define NR_PCA9539_GPIOS	16
+
+#define PCA9539_INPUT		0
+#define PCA9539_OUTPUT		2
+#define PCA9539_INVERT		4
+#define PCA9539_DIRECTION	6
+
+struct pca9539_chip {
+	unsigned gpio_start;
+	uint16_t reg_output;
+	uint16_t reg_direction;
+
+	struct i2c_client *client;
+	struct gpio_chip gpio_chip;
+};
+
+/* NOTE:  we can't currently rely on fault codes to come from SMBus
+ * calls, so we map all errors to EIO here and return zero otherwise.
+ */
+static int pca9539_write_reg(struct pca9539_chip *chip, int reg, uint16_t val)
+{
+	if (i2c_smbus_write_word_data(chip->client, reg, val) < 0)
+		return -EIO;
+	else
+		return 0;
+}
+
+static int pca9539_read_reg(struct pca9539_chip *chip, int reg, uint16_t *val)
+{
+	int ret;
+
+	ret = i2c_smbus_read_word_data(chip->client, reg);
+	if (ret < 0) {
+		dev_err(&chip->client->dev, "failed reading register\n");
+		return -EIO;
+	}
+
+	*val = (uint16_t)ret;
+	return 0;
+}
+
+static int pca9539_gpio_direction_input(struct gpio_chip *gc, unsigned off)
+{
+	struct pca9539_chip *chip;
+	uint16_t reg_val;
+	int ret;
+
+	chip = container_of(gc, struct pca9539_chip, gpio_chip);
+
+	reg_val = chip->reg_direction | (1u << off);
+	ret = pca9539_write_reg(chip, PCA9539_DIRECTION, reg_val);
+	if (ret)
+		return ret;
+
+	chip->reg_direction = reg_val;
+	return 0;
+}
+
+static int pca9539_gpio_direction_output(struct gpio_chip *gc,
+		unsigned off, int val)
+{
+	struct pca9539_chip *chip;
+	uint16_t reg_val;
+	int ret;
+
+	chip = container_of(gc, struct pca9539_chip, gpio_chip);
+
+	/* set output level */
+	if (val)
+		reg_val = chip->reg_output | (1u << off);
+	else
+		reg_val = chip->reg_output & ~(1u << off);
+
+	ret = pca9539_write_reg(chip, PCA9539_OUTPUT, reg_val);
+	if (ret)
+		return ret;
+
+	chip->reg_output = reg_val;
+
+	/* then direction */
+	reg_val = chip->reg_direction & ~(1u << off);
+	ret = pca9539_write_reg(chip, PCA9539_DIRECTION, reg_val);
+	if (ret)
+		return ret;
+
+	chip->reg_direction = reg_val;
+	return 0;
+}
+
+static int pca9539_gpio_get_value(struct gpio_chip *gc, unsigned off)
+{
+	struct pca9539_chip *chip;
+	uint16_t reg_val;
+	int ret;
+
+	chip = container_of(gc, struct pca9539_chip, gpio_chip);
+
+	ret = pca9539_read_reg(chip, PCA9539_INPUT, &reg_val);
+	if (ret < 0) {
+		/* NOTE:  diagnostic already emitted; that's all we should
+		 * do unless gpio_*_value_cansleep() calls become different
+		 * from their nonsleeping siblings (and report faults).
+		 */
+		return 0;
+	}
+
+	return (reg_val & (1u << off)) ? 1 : 0;
+}
+
+static void pca9539_gpio_set_value(struct gpio_chip *gc, unsigned off, int val)
+{
+	struct pca9539_chip *chip;
+	uint16_t reg_val;
+	int ret;
+
+	chip = container_of(gc, struct pca9539_chip, gpio_chip);
+
+	if (val)
+		reg_val = chip->reg_output | (1u << off);
+	else
+		reg_val = chip->reg_output & ~(1u << off);
+
+	ret = pca9539_write_reg(chip, PCA9539_OUTPUT, reg_val);
+	if (ret)
+		return;
+
+	chip->reg_output = reg_val;
+}
+
+static int pca9539_init_gpio(struct pca9539_chip *chip)
+{
+	struct gpio_chip *gc;
+
+	gc = &chip->gpio_chip;
+
+	gc->direction_input  = pca9539_gpio_direction_input;
+	gc->direction_output = pca9539_gpio_direction_output;
+	gc->get = pca9539_gpio_get_value;
+	gc->set = pca9539_gpio_set_value;
+
+	gc->base = chip->gpio_start;
+	gc->ngpio = NR_PCA9539_GPIOS;
+	gc->label = "pca9539";
+
+	return gpiochip_add(gc);
+}
+
+static int __devinit pca9539_probe(struct i2c_client *client)
+{
+	struct pca9539_platform_data *pdata;
+	struct pca9539_chip *chip;
+	int ret;
+
+	pdata = client->dev.platform_data;
+	if (pdata == NULL)
+		return -ENODEV;
+
+	chip = kzalloc(sizeof(struct pca9539_chip), GFP_KERNEL);
+	if (chip == NULL)
+		return -ENOMEM;
+
+	chip->client = client;
+
+	chip->gpio_start = pdata->gpio_base;
+
+	/* initialize cached registers from their original values.
+	 * we can't share this chip with another i2c master.
+	 */
+	ret = pca9539_read_reg(chip, PCA9539_OUTPUT, &chip->reg_output);
+	if (ret)
+		goto out_failed;
+
+	ret = pca9539_read_reg(chip, PCA9539_DIRECTION, &chip->reg_direction);
+	if (ret)
+		goto out_failed;
+
+	/* set platform specific polarity inversion */
+	ret = pca9539_write_reg(chip, PCA9539_INVERT, pdata->invert);
+	if (ret)
+		goto out_failed;
+
+	ret = pca9539_init_gpio(chip);
+	if (ret)
+		goto out_failed;
+
+	if (pdata->setup) {
+		ret = pdata->setup(client, chip->gpio_chip.base,
+				chip->gpio_chip.ngpio, pdata->context);
+		if (ret < 0)
+			dev_warn(&client->dev, "setup failed, %d\n", ret);
+	}
+
+	i2c_set_clientdata(client, chip);
+	return 0;
+
+out_failed:
+	kfree(chip);
+	return ret;
+}
+
+static int pca9539_remove(struct i2c_client *client)
+{
+	struct pca9539_platform_data *pdata = client->dev.platform_data;
+	struct pca9539_chip *chip = i2c_get_clientdata(client);
+	int ret = 0;
+
+	if (pdata->teardown) {
+		ret = pdata->teardown(client, chip->gpio_chip.base,
+				chip->gpio_chip.ngpio, pdata->context);
+		if (ret < 0) {
+			dev_err(&client->dev, "%s failed, %d\n",
+					"teardown", ret);
+			return ret;
+		}
+	}
+
+	ret = gpiochip_remove(&chip->gpio_chip);
+	if (ret) {
+		dev_err(&client->dev, "%s failed, %d\n",
+				"gpiochip_remove()", ret);
+		return ret;
+	}
+
+	kfree(chip);
+	return 0;
+}
+
+static struct i2c_driver pca9539_driver = {
+	.driver = {
+		.name	= "pca9539",
+	},
+	.probe		= pca9539_probe,
+	.remove		= pca9539_remove,
+};
+
+static int __init pca9539_init(void)
+{
+	return i2c_add_driver(&pca9539_driver);
+}
+module_init(pca9539_init);
+
+static void __exit pca9539_exit(void)
+{
+	i2c_del_driver(&pca9539_driver);
+}
+module_exit(pca9539_exit);
+
+MODULE_AUTHOR("eric miao <eric.miao@marvell.com>");
+MODULE_DESCRIPTION("GPIO expander driver for PCA9539");
+MODULE_LICENSE("GPL");