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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Core driver for WM8400.
*
* Copyright 2008 Wolfson Microelectronics PLC.
*
* Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
*/
#include <linux/init.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;
}
}
static int wm8400_register_codec(struct wm8400 *wm8400)
{
const struct mfd_cell cell = {
.name = "wm8400-codec",
.platform_data = wm8400,
.pdata_size = sizeof(*wm8400),
};
return devm_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;
/* 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");
return ret;
}
if (pdata && pdata->platform_init) {
ret = pdata->platform_init(wm8400->dev);
if (ret != 0) {
dev_err(wm8400->dev, "Platform init failed: %d\n",
ret);
return ret;
}
} else
dev_warn(wm8400->dev, "No platform initialisation supplied\n");
return 0;
}
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_MAPLE,
};
/**
* wm8400_reset_codec_reg_cache - Reset cached codec registers to
* their default values.
*
* @wm8400: pointer to local driver data structure
*/
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 IS_ENABLED(CONFIG_I2C)
static int wm8400_i2c_probe(struct i2c_client *i2c)
{
struct wm8400 *wm8400;
wm8400 = devm_kzalloc(&i2c->dev, sizeof(struct wm8400), GFP_KERNEL);
if (!wm8400)
return -ENOMEM;
wm8400->regmap = devm_regmap_init_i2c(i2c, &wm8400_regmap_config);
if (IS_ERR(wm8400->regmap))
return PTR_ERR(wm8400->regmap);
wm8400->dev = &i2c->dev;
i2c_set_clientdata(i2c, wm8400);
return wm8400_init(wm8400, dev_get_platdata(&i2c->dev));
}
static const struct i2c_device_id wm8400_i2c_id[] = {
{ "wm8400", 0 },
{ }
};
static struct i2c_driver wm8400_i2c_driver = {
.driver = {
.name = "WM8400",
},
.probe = wm8400_i2c_probe,
.id_table = wm8400_i2c_id,
};
#endif
static int __init wm8400_driver_init(void)
{
int ret = -ENODEV;
#if IS_ENABLED(CONFIG_I2C)
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_driver_init);
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