diff options
Diffstat (limited to 'drivers/mfd/max8907c.c')
| -rw-r--r-- | drivers/mfd/max8907c.c | 251 |
1 files changed, 251 insertions, 0 deletions
diff --git a/drivers/mfd/max8907c.c b/drivers/mfd/max8907c.c new file mode 100644 index 000000000000..0ceccbab7e37 --- /dev/null +++ b/drivers/mfd/max8907c.c @@ -0,0 +1,251 @@ +/* + * max8907c.c - mfd driver for MAX8907c + * + * Copyright (C) 2010 Gyungoh Yoo <jack.yoo@maxim-ic.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/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/mfd/core.h> +#include <linux/mfd/max8907c.h> + +static struct mfd_cell cells[] = { + {.name = "max8907-regulator",}, +}; + +int max8907c_reg_read(struct device *dev, u8 reg) +{ + struct i2c_client *i2c = to_i2c_client(dev); + struct max8907c *max8907c = dev_get_drvdata(dev); + u8 val; + int ret; + + mutex_lock(&max8907c->io_lock); + + ret = max8907c->read_dev(i2c, reg, 1, &val); + + mutex_unlock(&max8907c->io_lock); + pr_debug("max8907c: reg read reg=%x, val=%x\n", + (unsigned int)reg, (unsigned int)val); + + if (ret != 0) + pr_err("Failed to read max8907c I2C driver: %d\n", ret); + return val; +} +EXPORT_SYMBOL_GPL(max8907c_reg_read); + +int max8907c_reg_write(struct device *dev, u8 reg, u8 val) +{ + struct i2c_client *i2c = to_i2c_client(dev); + struct max8907c *max8907c = dev_get_drvdata(dev); + int ret; + + pr_debug("max8907c: reg write reg=%x, val=%x\n", + (unsigned int)reg, (unsigned int)val); + mutex_lock(&max8907c->io_lock); + + ret = max8907c->write_dev(i2c, reg, 1, &val); + + mutex_unlock(&max8907c->io_lock); + + if (ret != 0) + pr_err("Failed to write max8907c I2C driver: %d\n", ret); + return ret; +} +EXPORT_SYMBOL_GPL(max8907c_reg_write); + +int max8907c_set_bits(struct device *dev, u8 reg, u8 mask, u8 val) +{ + struct i2c_client *i2c = to_i2c_client(dev); + struct max8907c *max8907c = dev_get_drvdata(dev); + u8 tmp; + int ret; + + pr_debug("max8907c: reg write reg=%02X, val=%02X, mask=%02X\n", + (unsigned int)reg, (unsigned int)val, (unsigned int)mask); + mutex_lock(&max8907c->io_lock); + + ret = max8907c->read_dev(i2c, reg, 1, &tmp); + if (ret == 0) { + val = (tmp & ~mask) | (val & mask); + ret = max8907c->write_dev(i2c, reg, 1, &val); + } + + mutex_unlock(&max8907c->io_lock); + + if (ret != 0) + pr_err("Failed to write max8907c I2C driver: %d\n", ret); + return ret; +} +EXPORT_SYMBOL_GPL(max8907c_set_bits); + +static int max8907c_i2c_read(void *io_data, u8 reg, u8 count, u8 * dest) +{ + struct i2c_client *i2c = (struct i2c_client *)io_data; + struct i2c_msg xfer[2]; + int ret = 0; + + xfer[0].addr = i2c->addr; + xfer[0].flags = I2C_M_NOSTART; + xfer[0].len = 1; + xfer[0].buf = ® + + xfer[1].addr = i2c->addr; + xfer[1].flags = I2C_M_RD; + xfer[1].len = count; + xfer[1].buf = dest; + + ret = i2c_transfer(i2c->adapter, xfer, 2); + if (ret < 0) + return ret; + if (ret != 2) + return -EIO; + + return 0; +} + +static int max8907c_i2c_write(void *io_data, u8 reg, u8 count, const u8 * src) +{ + struct i2c_client *i2c = (struct i2c_client *)io_data; + u8 msg[0x100 + 1]; + int ret = 0; + + msg[0] = reg; + memcpy(&msg[1], src, count); + + ret = i2c_master_send(i2c, msg, count + 1); + if (ret < 0) + return ret; + if (ret != count + 1) + return -EIO; + + return 0; +} + +static int max8907c_remove_subdev(struct device *dev, void *unused) +{ + platform_device_unregister(to_platform_device(dev)); + return 0; +} + +static int max8907c_remove_subdevs(struct max8907c *max8907c) +{ + return device_for_each_child(max8907c->dev, NULL, + max8907c_remove_subdev); +} + +static int max8097c_add_subdevs(struct max8907c *max8907c, + struct max8907c_platform_data *pdata) +{ + struct platform_device *pdev; + int ret; + int i; + + for (i = 0; i < pdata->num_subdevs; i++) { + pdev = platform_device_alloc(pdata->subdevs[i]->name, + pdata->subdevs[i]->id); + + pdev->dev.parent = max8907c->dev; + pdev->dev.platform_data = pdata->subdevs[i]->dev.platform_data; + + ret = platform_device_add(pdev); + if (ret) + goto error; + } + return 0; + +error: + max8907c_remove_subdevs(max8907c); + return ret; +} + +static int max8907c_i2c_probe(struct i2c_client *i2c, + const struct i2c_device_id *id) +{ + struct max8907c *max8907c; + struct max8907c_platform_data *pdata = i2c->dev.platform_data; + int ret; + int i; + + max8907c = kzalloc(sizeof(struct max8907c), GFP_KERNEL); + if (max8907c == NULL) + return -ENOMEM; + + max8907c->read_dev = max8907c_i2c_read; + max8907c->write_dev = max8907c_i2c_write; + max8907c->dev = &i2c->dev; + i2c_set_clientdata(i2c, max8907c); + + mutex_init(&max8907c->io_lock); + + for (i = 0; i < ARRAY_SIZE(cells); i++) + cells[i].driver_data = max8907c; + ret = mfd_add_devices(max8907c->dev, -1, cells, ARRAY_SIZE(cells), + NULL, 0); + if (ret != 0) { + kfree(max8907c); + pr_debug("max8907c: failed to add MFD devices %X\n", ret); + return ret; + } + + ret = max8097c_add_subdevs(max8907c, pdata); + + return ret; +} + +static int max8907c_i2c_remove(struct i2c_client *i2c) +{ + struct max8907c *max8907c = i2c_get_clientdata(i2c); + + mfd_remove_devices(max8907c->dev); + kfree(max8907c); + + return 0; +} + +static const struct i2c_device_id max8907c_i2c_id[] = { + {"max8907c", 0}, + {} +}; + +MODULE_DEVICE_TABLE(i2c, max8907c_i2c_id); + +static struct i2c_driver max8907c_i2c_driver = { + .driver = { + .name = "max8907c", + .owner = THIS_MODULE, + }, + .probe = max8907c_i2c_probe, + .remove = max8907c_i2c_remove, + .id_table = max8907c_i2c_id, +}; + +static int __init max8907c_i2c_init(void) +{ + int ret = -ENODEV; + + ret = i2c_add_driver(&max8907c_i2c_driver); + if (ret != 0) + pr_err("Failed to register I2C driver: %d\n", ret); + + return ret; +} + +subsys_initcall(max8907c_i2c_init); + +static void __exit max8907c_i2c_exit(void) +{ + i2c_del_driver(&max8907c_i2c_driver); +} + +module_exit(max8907c_i2c_exit); + +MODULE_DESCRIPTION("MAX8907C multi-function core driver"); +MODULE_AUTHOR("Gyungoh Yoo <jack.yoo@maxim-ic.com>"); +MODULE_LICENSE("GPL"); |