summaryrefslogtreecommitdiff
path: root/drivers/mfd/max8925-i2c.c
diff options
context:
space:
mode:
authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /drivers/mfd/max8925-i2c.c
Initial import
Diffstat (limited to 'drivers/mfd/max8925-i2c.c')
-rw-r--r--drivers/mfd/max8925-i2c.c277
1 files changed, 277 insertions, 0 deletions
diff --git a/drivers/mfd/max8925-i2c.c b/drivers/mfd/max8925-i2c.c
new file mode 100644
index 000000000..c880c895c
--- /dev/null
+++ b/drivers/mfd/max8925-i2c.c
@@ -0,0 +1,277 @@
+/*
+ * I2C driver for Maxim MAX8925
+ *
+ * Copyright (C) 2009 Marvell International Ltd.
+ * Haojian Zhuang <haojian.zhuang@marvell.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.
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+#include <linux/mfd/max8925.h>
+#include <linux/slab.h>
+
+#define RTC_I2C_ADDR 0x68
+#define ADC_I2C_ADDR 0x47
+
+static inline int max8925_read_device(struct i2c_client *i2c,
+ int reg, int bytes, void *dest)
+{
+ int ret;
+
+ if (bytes > 1)
+ ret = i2c_smbus_read_i2c_block_data(i2c, reg, bytes, dest);
+ else {
+ ret = i2c_smbus_read_byte_data(i2c, reg);
+ if (ret < 0)
+ return ret;
+ *(unsigned char *)dest = (unsigned char)ret;
+ }
+ return ret;
+}
+
+static inline int max8925_write_device(struct i2c_client *i2c,
+ int reg, int bytes, void *src)
+{
+ unsigned char buf[9];
+ int ret;
+
+ buf[0] = (unsigned char)reg;
+ memcpy(&buf[1], src, bytes);
+
+ ret = i2c_master_send(i2c, buf, bytes + 1);
+ if (ret < 0)
+ return ret;
+ return 0;
+}
+
+int max8925_reg_read(struct i2c_client *i2c, int reg)
+{
+ struct max8925_chip *chip = i2c_get_clientdata(i2c);
+ unsigned char data = 0;
+ int ret;
+
+ mutex_lock(&chip->io_lock);
+ ret = max8925_read_device(i2c, reg, 1, &data);
+ mutex_unlock(&chip->io_lock);
+
+ if (ret < 0)
+ return ret;
+ else
+ return (int)data;
+}
+EXPORT_SYMBOL(max8925_reg_read);
+
+int max8925_reg_write(struct i2c_client *i2c, int reg,
+ unsigned char data)
+{
+ struct max8925_chip *chip = i2c_get_clientdata(i2c);
+ int ret;
+
+ mutex_lock(&chip->io_lock);
+ ret = max8925_write_device(i2c, reg, 1, &data);
+ mutex_unlock(&chip->io_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(max8925_reg_write);
+
+int max8925_bulk_read(struct i2c_client *i2c, int reg,
+ int count, unsigned char *buf)
+{
+ struct max8925_chip *chip = i2c_get_clientdata(i2c);
+ int ret;
+
+ mutex_lock(&chip->io_lock);
+ ret = max8925_read_device(i2c, reg, count, buf);
+ mutex_unlock(&chip->io_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(max8925_bulk_read);
+
+int max8925_bulk_write(struct i2c_client *i2c, int reg,
+ int count, unsigned char *buf)
+{
+ struct max8925_chip *chip = i2c_get_clientdata(i2c);
+ int ret;
+
+ mutex_lock(&chip->io_lock);
+ ret = max8925_write_device(i2c, reg, count, buf);
+ mutex_unlock(&chip->io_lock);
+
+ return ret;
+}
+EXPORT_SYMBOL(max8925_bulk_write);
+
+int max8925_set_bits(struct i2c_client *i2c, int reg,
+ unsigned char mask, unsigned char data)
+{
+ struct max8925_chip *chip = i2c_get_clientdata(i2c);
+ unsigned char value;
+ int ret;
+
+ mutex_lock(&chip->io_lock);
+ ret = max8925_read_device(i2c, reg, 1, &value);
+ if (ret < 0)
+ goto out;
+ value &= ~mask;
+ value |= data;
+ ret = max8925_write_device(i2c, reg, 1, &value);
+out:
+ mutex_unlock(&chip->io_lock);
+ return ret;
+}
+EXPORT_SYMBOL(max8925_set_bits);
+
+
+static const struct i2c_device_id max8925_id_table[] = {
+ { "max8925", 0 },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, max8925_id_table);
+
+static int max8925_dt_init(struct device_node *np, struct device *dev,
+ struct max8925_platform_data *pdata)
+{
+ int ret;
+
+ ret = of_property_read_u32(np, "maxim,tsc-irq", &pdata->tsc_irq);
+ if (ret) {
+ dev_err(dev, "Not found maxim,tsc-irq property\n");
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static int max8925_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct max8925_platform_data *pdata = dev_get_platdata(&client->dev);
+ static struct max8925_chip *chip;
+ struct device_node *node = client->dev.of_node;
+
+ if (node && !pdata) {
+ /* parse DT to get platform data */
+ pdata = devm_kzalloc(&client->dev,
+ sizeof(struct max8925_platform_data),
+ GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+
+ if (max8925_dt_init(node, &client->dev, pdata))
+ return -EINVAL;
+ } else if (!pdata) {
+ pr_info("%s: platform data is missing\n", __func__);
+ return -EINVAL;
+ }
+
+ chip = devm_kzalloc(&client->dev,
+ sizeof(struct max8925_chip), GFP_KERNEL);
+ if (chip == NULL)
+ return -ENOMEM;
+ chip->i2c = client;
+ chip->dev = &client->dev;
+ i2c_set_clientdata(client, chip);
+ dev_set_drvdata(chip->dev, chip);
+ mutex_init(&chip->io_lock);
+
+ chip->rtc = i2c_new_dummy(chip->i2c->adapter, RTC_I2C_ADDR);
+ if (!chip->rtc) {
+ dev_err(chip->dev, "Failed to allocate I2C device for RTC\n");
+ return -ENODEV;
+ }
+ i2c_set_clientdata(chip->rtc, chip);
+
+ chip->adc = i2c_new_dummy(chip->i2c->adapter, ADC_I2C_ADDR);
+ if (!chip->adc) {
+ dev_err(chip->dev, "Failed to allocate I2C device for ADC\n");
+ i2c_unregister_device(chip->rtc);
+ return -ENODEV;
+ }
+ i2c_set_clientdata(chip->adc, chip);
+
+ device_init_wakeup(&client->dev, 1);
+
+ max8925_device_init(chip, pdata);
+
+ return 0;
+}
+
+static int max8925_remove(struct i2c_client *client)
+{
+ struct max8925_chip *chip = i2c_get_clientdata(client);
+
+ max8925_device_exit(chip);
+ i2c_unregister_device(chip->adc);
+ i2c_unregister_device(chip->rtc);
+ return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int max8925_suspend(struct device *dev)
+{
+ struct i2c_client *client = container_of(dev, struct i2c_client, dev);
+ struct max8925_chip *chip = i2c_get_clientdata(client);
+
+ if (device_may_wakeup(dev) && chip->wakeup_flag)
+ enable_irq_wake(chip->core_irq);
+ return 0;
+}
+
+static int max8925_resume(struct device *dev)
+{
+ struct i2c_client *client = container_of(dev, struct i2c_client, dev);
+ struct max8925_chip *chip = i2c_get_clientdata(client);
+
+ if (device_may_wakeup(dev) && chip->wakeup_flag)
+ disable_irq_wake(chip->core_irq);
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(max8925_pm_ops, max8925_suspend, max8925_resume);
+
+static const struct of_device_id max8925_dt_ids[] = {
+ { .compatible = "maxim,max8925", },
+ {},
+};
+MODULE_DEVICE_TABLE(of, max8925_dt_ids);
+
+static struct i2c_driver max8925_driver = {
+ .driver = {
+ .name = "max8925",
+ .owner = THIS_MODULE,
+ .pm = &max8925_pm_ops,
+ .of_match_table = max8925_dt_ids,
+ },
+ .probe = max8925_probe,
+ .remove = max8925_remove,
+ .id_table = max8925_id_table,
+};
+
+static int __init max8925_i2c_init(void)
+{
+ int ret;
+
+ ret = i2c_add_driver(&max8925_driver);
+ if (ret != 0)
+ pr_err("Failed to register MAX8925 I2C driver: %d\n", ret);
+
+ return ret;
+}
+subsys_initcall(max8925_i2c_init);
+
+static void __exit max8925_i2c_exit(void)
+{
+ i2c_del_driver(&max8925_driver);
+}
+module_exit(max8925_i2c_exit);
+
+MODULE_DESCRIPTION("I2C Driver for Maxim 8925");
+MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
+MODULE_LICENSE("GPL");