/* * Core driver for WM8400. * * Copyright 2008 Wolfson Microelectronics PLC. * * Author: Mark Brown <broonie@opensource.wolfsonmicro.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/module.h> #include <linux/bug.h> #include <linux/err.h> #include <linux/i2c.h> #include <linux/kernel.h> #include <linux/mfd/core.h> #include <linux/mfd/wm8400-private.h> #include <linux/mfd/wm8400-audio.h> #include <linux/regmap.h> #include <linux/slab.h> static bool wm8400_volatile(struct device *dev, unsigned int reg) { switch (reg) { case WM8400_INTERRUPT_STATUS_1: case WM8400_INTERRUPT_LEVELS: case WM8400_SHUTDOWN_REASON: return true; default: return false; } } /** * wm8400_reg_read - Single register read * * @wm8400: Pointer to wm8400 control structure * @reg: Register to read * * @return Read value */ u16 wm8400_reg_read(struct wm8400 *wm8400, u8 reg) { unsigned int val; int ret; ret = regmap_read(wm8400->regmap, reg, &val); if (ret < 0) return ret; return val; } EXPORT_SYMBOL_GPL(wm8400_reg_read); int wm8400_block_read(struct wm8400 *wm8400, u8 reg, int count, u16 *data) { return regmap_bulk_read(wm8400->regmap, reg, data, count); } EXPORT_SYMBOL_GPL(wm8400_block_read); static int wm8400_register_codec(struct wm8400 *wm8400) { struct mfd_cell cell = { .name = "wm8400-codec", .platform_data = wm8400, .pdata_size = sizeof(*wm8400), }; return mfd_add_devices(wm8400->dev, -1, &cell, 1, NULL, 0, NULL); } /* * wm8400_init - Generic initialisation * * The WM8400 can be configured as either an I2C or SPI device. Probe * functions for each bus set up the accessors then call into this to * set up the device itself. */ static int wm8400_init(struct wm8400 *wm8400, struct wm8400_platform_data *pdata) { unsigned int reg; int ret; dev_set_drvdata(wm8400->dev, wm8400); /* Check that this is actually a WM8400 */ ret = regmap_read(wm8400->regmap, WM8400_RESET_ID, ®); if (ret != 0) { dev_err(wm8400->dev, "Chip ID register read failed\n"); return -EIO; } if (reg != 0x6172) { dev_err(wm8400->dev, "Device is not a WM8400, ID is %x\n", reg); return -ENODEV; } ret = regmap_read(wm8400->regmap, WM8400_ID, ®); if (ret != 0) { dev_err(wm8400->dev, "ID register read failed: %d\n", ret); return ret; } reg = (reg & WM8400_CHIP_REV_MASK) >> WM8400_CHIP_REV_SHIFT; dev_info(wm8400->dev, "WM8400 revision %x\n", reg); ret = wm8400_register_codec(wm8400); if (ret != 0) { dev_err(wm8400->dev, "Failed to register codec\n"); goto err_children; } if (pdata && pdata->platform_init) { ret = pdata->platform_init(wm8400->dev); if (ret != 0) { dev_err(wm8400->dev, "Platform init failed: %d\n", ret); goto err_children; } } else dev_warn(wm8400->dev, "No platform initialisation supplied\n"); return 0; err_children: mfd_remove_devices(wm8400->dev); return ret; } static void wm8400_release(struct wm8400 *wm8400) { mfd_remove_devices(wm8400->dev); } static const struct regmap_config wm8400_regmap_config = { .reg_bits = 8, .val_bits = 16, .max_register = WM8400_REGISTER_COUNT - 1, .volatile_reg = wm8400_volatile, .cache_type = REGCACHE_RBTREE, }; /** * wm8400_reset_codec_reg_cache - Reset cached codec registers to * their default values. */ void wm8400_reset_codec_reg_cache(struct wm8400 *wm8400) { regmap_reinit_cache(wm8400->regmap, &wm8400_regmap_config); } EXPORT_SYMBOL_GPL(wm8400_reset_codec_reg_cache); #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) static int wm8400_i2c_probe(struct i2c_client *i2c, const struct i2c_device_id *id) { struct wm8400 *wm8400; int ret; wm8400 = devm_kzalloc(&i2c->dev, sizeof(struct wm8400), GFP_KERNEL); if (wm8400 == NULL) { ret = -ENOMEM; goto err; } wm8400->regmap = devm_regmap_init_i2c(i2c, &wm8400_regmap_config); if (IS_ERR(wm8400->regmap)) { ret = PTR_ERR(wm8400->regmap); goto err; } wm8400->dev = &i2c->dev; i2c_set_clientdata(i2c, wm8400); ret = wm8400_init(wm8400, i2c->dev.platform_data); if (ret != 0) goto err; return 0; err: return ret; } static int wm8400_i2c_remove(struct i2c_client *i2c) { struct wm8400 *wm8400 = i2c_get_clientdata(i2c); wm8400_release(wm8400); return 0; } static const struct i2c_device_id wm8400_i2c_id[] = { { "wm8400", 0 }, { } }; MODULE_DEVICE_TABLE(i2c, wm8400_i2c_id); static struct i2c_driver wm8400_i2c_driver = { .driver = { .name = "WM8400", .owner = THIS_MODULE, }, .probe = wm8400_i2c_probe, .remove = wm8400_i2c_remove, .id_table = wm8400_i2c_id, }; #endif static int __init wm8400_module_init(void) { int ret = -ENODEV; #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) ret = i2c_add_driver(&wm8400_i2c_driver); if (ret != 0) pr_err("Failed to register I2C driver: %d\n", ret); #endif return ret; } subsys_initcall(wm8400_module_init); static void __exit wm8400_module_exit(void) { #if defined(CONFIG_I2C) || defined(CONFIG_I2C_MODULE) i2c_del_driver(&wm8400_i2c_driver); #endif } module_exit(wm8400_module_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("Mark Brown <broonie@opensource.wolfsonmicro.com>");