summaryrefslogtreecommitdiffstats
path: root/drivers/gpio/gpio-tpic2810.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/gpio/gpio-tpic2810.c')
-rw-r--r--drivers/gpio/gpio-tpic2810.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/drivers/gpio/gpio-tpic2810.c b/drivers/gpio/gpio-tpic2810.c
new file mode 100644
index 000000000000..032d058c0d28
--- /dev/null
+++ b/drivers/gpio/gpio-tpic2810.c
@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com/
+ * Andrew F. Davis <afd@ti.com>
+ *
+ * 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 program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether expressed or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License version 2 for more details.
+ */
+
+#include <linux/gpio/driver.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+
+#define TPIC2810_WS_COMMAND 0x44
+
+/**
+ * struct tpic2810 - GPIO driver data
+ * @chip: GPIO controller chip
+ * @client: I2C device pointer
+ * @buffer: Buffer for device register
+ * @lock: Protects write sequences
+ */
+struct tpic2810 {
+ struct gpio_chip chip;
+ struct i2c_client *client;
+ u8 buffer;
+ struct mutex lock;
+};
+
+static int tpic2810_get_direction(struct gpio_chip *chip,
+ unsigned offset)
+{
+ /* This device always output */
+ return 0;
+}
+
+static int tpic2810_direction_input(struct gpio_chip *chip,
+ unsigned offset)
+{
+ /* This device is output only */
+ return -EINVAL;
+}
+
+static int tpic2810_direction_output(struct gpio_chip *chip,
+ unsigned offset, int value)
+{
+ /* This device always output */
+ return 0;
+}
+
+static void tpic2810_set(struct gpio_chip *chip, unsigned offset, int value)
+{
+ struct tpic2810 *gpio = gpiochip_get_data(chip);
+
+ mutex_lock(&gpio->lock);
+
+ if (value)
+ gpio->buffer |= BIT(offset);
+ else
+ gpio->buffer &= ~BIT(offset);
+
+ i2c_smbus_write_byte_data(gpio->client, TPIC2810_WS_COMMAND,
+ gpio->buffer);
+
+ mutex_unlock(&gpio->lock);
+}
+
+static void tpic2810_set_multiple(struct gpio_chip *chip, unsigned long *mask,
+ unsigned long *bits)
+{
+ struct tpic2810 *gpio = gpiochip_get_data(chip);
+
+ mutex_lock(&gpio->lock);
+
+ /* clear bits under mask */
+ gpio->buffer &= ~(*mask);
+ /* set bits under mask */
+ gpio->buffer |= ((*mask) & (*bits));
+
+ i2c_smbus_write_byte_data(gpio->client, TPIC2810_WS_COMMAND,
+ gpio->buffer);
+
+ mutex_unlock(&gpio->lock);
+}
+
+static struct gpio_chip template_chip = {
+ .label = "tpic2810",
+ .owner = THIS_MODULE,
+ .get_direction = tpic2810_get_direction,
+ .direction_input = tpic2810_direction_input,
+ .direction_output = tpic2810_direction_output,
+ .set = tpic2810_set,
+ .set_multiple = tpic2810_set_multiple,
+ .base = -1,
+ .ngpio = 8,
+ .can_sleep = true,
+};
+
+static const struct of_device_id tpic2810_of_match_table[] = {
+ { .compatible = "ti,tpic2810" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, tpic2810_of_match_table);
+
+static int tpic2810_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct tpic2810 *gpio;
+ int ret;
+
+ gpio = devm_kzalloc(&client->dev, sizeof(*gpio), GFP_KERNEL);
+ if (!gpio)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, gpio);
+
+ gpio->chip = template_chip;
+ gpio->chip.parent = &client->dev;
+
+ gpio->client = client;
+
+ mutex_init(&gpio->lock);
+
+ ret = gpiochip_add_data(&gpio->chip, gpio);
+ if (ret < 0) {
+ dev_err(&client->dev, "Unable to register gpiochip\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+static int tpic2810_remove(struct i2c_client *client)
+{
+ struct tpic2810 *gpio = i2c_get_clientdata(client);
+
+ gpiochip_remove(&gpio->chip);
+
+ return 0;
+}
+
+static const struct i2c_device_id tpic2810_id_table[] = {
+ { "tpic2810", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(i2c, tpic2810_id_table);
+
+static struct i2c_driver tpic2810_driver = {
+ .driver = {
+ .name = "tpic2810",
+ .of_match_table = tpic2810_of_match_table,
+ },
+ .probe = tpic2810_probe,
+ .remove = tpic2810_remove,
+ .id_table = tpic2810_id_table,
+};
+module_i2c_driver(tpic2810_driver);
+
+MODULE_AUTHOR("Andrew F. Davis <afd@ti.com>");
+MODULE_DESCRIPTION("TPIC2810 8-Bit LED Driver GPIO Driver");
+MODULE_LICENSE("GPL v2");