--- /dev/null
+/*
+ * 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)
+{
+ const 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;
+
+ 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 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>");
Code Review / kvmfornfv.git / blobdiff