diff options
Diffstat (limited to 'drivers/mfd/da9052-i2c.c')
| -rw-r--r-- | drivers/mfd/da9052-i2c.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/drivers/mfd/da9052-i2c.c b/drivers/mfd/da9052-i2c.c new file mode 100644 index 000000000..4094f97ec --- /dev/null +++ b/drivers/mfd/da9052-i2c.c @@ -0,0 +1,223 @@ +/* + * I2C access for DA9052 PMICs. + * + * Copyright(c) 2011 Dialog Semiconductor Ltd. + * + * Author: David Dajun Chen <dchen@diasemi.com> + * + * 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; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include <linux/device.h> +#include <linux/module.h> +#include <linux/input.h> +#include <linux/mfd/core.h> +#include <linux/i2c.h> +#include <linux/err.h> + +#include <linux/mfd/da9052/da9052.h> +#include <linux/mfd/da9052/reg.h> + +#ifdef CONFIG_OF +#include <linux/of.h> +#include <linux/of_device.h> +#endif + +/* I2C safe register check */ +static inline bool i2c_safe_reg(unsigned char reg) +{ + switch (reg) { + case DA9052_STATUS_A_REG: + case DA9052_STATUS_B_REG: + case DA9052_STATUS_C_REG: + case DA9052_STATUS_D_REG: + case DA9052_ADC_RES_L_REG: + case DA9052_ADC_RES_H_REG: + case DA9052_VDD_RES_REG: + case DA9052_ICHG_AV_REG: + case DA9052_TBAT_RES_REG: + case DA9052_ADCIN4_RES_REG: + case DA9052_ADCIN5_RES_REG: + case DA9052_ADCIN6_RES_REG: + case DA9052_TJUNC_RES_REG: + case DA9052_TSI_X_MSB_REG: + case DA9052_TSI_Y_MSB_REG: + case DA9052_TSI_LSB_REG: + case DA9052_TSI_Z_MSB_REG: + return true; + default: + return false; + } +} + +/* + * There is an issue with DA9052 and DA9053_AA/BA/BB PMIC where the PMIC + * gets lockup up or fails to respond following a system reset. + * This fix is to follow any read or write with a dummy read to a safe + * register. + */ +static int da9052_i2c_fix(struct da9052 *da9052, unsigned char reg) +{ + int val; + + switch (da9052->chip_id) { + case DA9052: + case DA9053_AA: + case DA9053_BA: + case DA9053_BB: + /* A dummy read to a safe register address. */ + if (!i2c_safe_reg(reg)) + return regmap_read(da9052->regmap, + DA9052_PARK_REGISTER, + &val); + break; + case DA9053_BC: + default: + /* + * For other chips parking of I2C register + * to a safe place is not required. + */ + break; + } + + return 0; +} + +/* + * According to errata item 24, multiwrite mode should be avoided + * in order to prevent register data corruption after power-down. + */ +static int da9052_i2c_disable_multiwrite(struct da9052 *da9052) +{ + int reg_val, ret; + + ret = regmap_read(da9052->regmap, DA9052_CONTROL_B_REG, ®_val); + if (ret < 0) + return ret; + + if (!(reg_val & DA9052_CONTROL_B_WRITEMODE)) { + reg_val |= DA9052_CONTROL_B_WRITEMODE; + ret = regmap_write(da9052->regmap, DA9052_CONTROL_B_REG, + reg_val); + if (ret < 0) + return ret; + } + + return 0; +} + +static const struct i2c_device_id da9052_i2c_id[] = { + {"da9052", DA9052}, + {"da9053-aa", DA9053_AA}, + {"da9053-ba", DA9053_BA}, + {"da9053-bb", DA9053_BB}, + {"da9053-bc", DA9053_BC}, + {} +}; +MODULE_DEVICE_TABLE(i2c, da9052_i2c_id); + +#ifdef CONFIG_OF +static const struct of_device_id dialog_dt_ids[] = { + { .compatible = "dlg,da9052", .data = &da9052_i2c_id[0] }, + { .compatible = "dlg,da9053-aa", .data = &da9052_i2c_id[1] }, + { .compatible = "dlg,da9053-ba", .data = &da9052_i2c_id[2] }, + { .compatible = "dlg,da9053-bb", .data = &da9052_i2c_id[3] }, + { .compatible = "dlg,da9053-bc", .data = &da9052_i2c_id[4] }, + { /* sentinel */ } +}; +#endif + +static int da9052_i2c_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct da9052 *da9052; + int ret; + + da9052 = devm_kzalloc(&client->dev, sizeof(struct da9052), GFP_KERNEL); + if (!da9052) + return -ENOMEM; + + da9052->dev = &client->dev; + da9052->chip_irq = client->irq; + da9052->fix_io = da9052_i2c_fix; + + i2c_set_clientdata(client, da9052); + + da9052->regmap = devm_regmap_init_i2c(client, &da9052_regmap_config); + if (IS_ERR(da9052->regmap)) { + ret = PTR_ERR(da9052->regmap); + dev_err(&client->dev, "Failed to allocate register map: %d\n", + ret); + return ret; + } + + ret = da9052_i2c_disable_multiwrite(da9052); + if (ret < 0) + return ret; + +#ifdef CONFIG_OF + if (!id) { + struct device_node *np = client->dev.of_node; + const struct of_device_id *deviceid; + + deviceid = of_match_node(dialog_dt_ids, np); + id = deviceid->data; + } +#endif + + if (!id) { + ret = -ENODEV; + dev_err(&client->dev, "id is null.\n"); + return ret; + } + + return da9052_device_init(da9052, id->driver_data); +} + +static int da9052_i2c_remove(struct i2c_client *client) +{ + struct da9052 *da9052 = i2c_get_clientdata(client); + + da9052_device_exit(da9052); + return 0; +} + +static struct i2c_driver da9052_i2c_driver = { + .probe = da9052_i2c_probe, + .remove = da9052_i2c_remove, + .id_table = da9052_i2c_id, + .driver = { + .name = "da9052", +#ifdef CONFIG_OF + .of_match_table = dialog_dt_ids, +#endif + }, +}; + +static int __init da9052_i2c_init(void) +{ + int ret; + + ret = i2c_add_driver(&da9052_i2c_driver); + if (ret != 0) { + pr_err("DA9052 I2C registration failed %d\n", ret); + return ret; + } + + return 0; +} +subsys_initcall(da9052_i2c_init); + +static void __exit da9052_i2c_exit(void) +{ + i2c_del_driver(&da9052_i2c_driver); +} +module_exit(da9052_i2c_exit); + +MODULE_AUTHOR("David Dajun Chen <dchen@diasemi.com>"); +MODULE_DESCRIPTION("I2C driver for Dialog DA9052 PMIC"); +MODULE_LICENSE("GPL"); |