alistair23-linux/drivers/mfd/wl1273-core.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * MFD driver for wl1273 FM radio and audio codec submodules.
 *
 * Copyright (C) 2011 Nokia Corporation
 * Author: Matti Aaltonen <matti.j.aaltonen@nokia.com>
 */

#include <linux/mfd/wl1273-core.h>
#include <linux/slab.h>
#include <linux/module.h>

#define DRIVER_DESC "WL1273 FM Radio Core"

static const struct i2c_device_id wl1273_driver_id_table[] = {
	{ WL1273_FM_DRIVER_NAME, 0 },
	{ }
};
MODULE_DEVICE_TABLE(i2c, wl1273_driver_id_table);

static int wl1273_fm_read_reg(struct wl1273_core *core, u8 reg, u16 *value)
{
	struct i2c_client *client = core->client;
	u8 b[2];
	int r;

	r = i2c_smbus_read_i2c_block_data(client, reg, sizeof(b), b);
	if (r != 2) {
		dev_err(&client->dev, "%s: Read: %d fails.\n", __func__, reg);
		return -EREMOTEIO;
	}

	*value = (u16)b[0] << 8 | b[1];

	return 0;
}

static int wl1273_fm_write_cmd(struct wl1273_core *core, u8 cmd, u16 param)
{
	struct i2c_client *client = core->client;
	u8 buf[] = { (param >> 8) & 0xff, param & 0xff };
	int r;

	r = i2c_smbus_write_i2c_block_data(client, cmd, sizeof(buf), buf);
	if (r) {
		dev_err(&client->dev, "%s: Cmd: %d fails.\n", __func__, cmd);
		return r;
	}

	return 0;
}

static int wl1273_fm_write_data(struct wl1273_core *core, u8 *data, u16 len)
{
	struct i2c_client *client = core->client;
	struct i2c_msg msg;
	int r;

	msg.addr = client->addr;
	msg.flags = 0;
	msg.buf = data;
	msg.len = len;

	r = i2c_transfer(client->adapter, &msg, 1);
	if (r != 1) {
		dev_err(&client->dev, "%s: write error.\n", __func__);
		return -EREMOTEIO;
	}

	return 0;
}

/**
 * wl1273_fm_set_audio() -	Set audio mode.
 * @core:			A pointer to the device struct.
 * @new_mode:			The new audio mode.
 *
 * Audio modes are WL1273_AUDIO_DIGITAL and WL1273_AUDIO_ANALOG.
 */
static int wl1273_fm_set_audio(struct wl1273_core *core, unsigned int new_mode)
{
	int r = 0;

	if (core->mode == WL1273_MODE_OFF ||
	    core->mode == WL1273_MODE_SUSPENDED)
		return -EPERM;

	if (core->mode == WL1273_MODE_RX && new_mode == WL1273_AUDIO_DIGITAL) {
		r = wl1273_fm_write_cmd(core, WL1273_PCM_MODE_SET,
					WL1273_PCM_DEF_MODE);
		if (r)
			goto out;

		r = wl1273_fm_write_cmd(core, WL1273_I2S_MODE_CONFIG_SET,
					core->i2s_mode);
		if (r)
			goto out;

		r = wl1273_fm_write_cmd(core, WL1273_AUDIO_ENABLE,
					WL1273_AUDIO_ENABLE_I2S);
		if (r)
			goto out;

	} else if (core->mode == WL1273_MODE_RX &&
		   new_mode == WL1273_AUDIO_ANALOG) {
		r = wl1273_fm_write_cmd(core, WL1273_AUDIO_ENABLE,
					WL1273_AUDIO_ENABLE_ANALOG);
		if (r)
			goto out;

	} else if (core->mode == WL1273_MODE_TX &&
		   new_mode == WL1273_AUDIO_DIGITAL) {
		r = wl1273_fm_write_cmd(core, WL1273_I2S_MODE_CONFIG_SET,
					core->i2s_mode);
		if (r)
			goto out;

		r = wl1273_fm_write_cmd(core, WL1273_AUDIO_IO_SET,
					WL1273_AUDIO_IO_SET_I2S);
		if (r)
			goto out;

	} else if (core->mode == WL1273_MODE_TX &&
		   new_mode == WL1273_AUDIO_ANALOG) {
		r = wl1273_fm_write_cmd(core, WL1273_AUDIO_IO_SET,
					WL1273_AUDIO_IO_SET_ANALOG);
		if (r)
			goto out;
	}

	core->audio_mode = new_mode;
out:
	return r;
}

/**
 * wl1273_fm_set_volume() -	Set volume.
 * @core:			A pointer to the device struct.
 * @volume:			The new volume value.
 */
static int wl1273_fm_set_volume(struct wl1273_core *core, unsigned int volume)
{
	int r;

	if (volume > WL1273_MAX_VOLUME)
		return -EINVAL;

	if (core->volume == volume)
		return 0;

	r = wl1273_fm_write_cmd(core, WL1273_VOLUME_SET, volume);
	if (r)
		return r;

	core->volume = volume;
	return 0;
}

static int wl1273_core_probe(struct i2c_client *client,
				       const struct i2c_device_id *id)
{
	struct wl1273_fm_platform_data *pdata = dev_get_platdata(&client->dev);
	struct wl1273_core *core;
	struct mfd_cell *cell;
	int children = 0;
	int r = 0;

	dev_dbg(&client->dev, "%s\n", __func__);

	if (!pdata) {
		dev_err(&client->dev, "No platform data.\n");
		return -EINVAL;
	}

	if (!(pdata->children & WL1273_RADIO_CHILD)) {
		dev_err(&client->dev, "Cannot function without radio child.\n");
		return -EINVAL;
	}

	core = devm_kzalloc(&client->dev, sizeof(*core), GFP_KERNEL);
	if (!core)
		return -ENOMEM;

	core->pdata = pdata;
	core->client = client;
	mutex_init(&core->lock);

	i2c_set_clientdata(client, core);

	dev_dbg(&client->dev, "%s: Have V4L2.\n", __func__);

	cell = &core->cells[children];
	cell->name = "wl1273_fm_radio";
	cell->platform_data = &core;
	cell->pdata_size = sizeof(core);
	children++;

	core->read = wl1273_fm_read_reg;
	core->write = wl1273_fm_write_cmd;
	core->write_data = wl1273_fm_write_data;
	core->set_audio = wl1273_fm_set_audio;
	core->set_volume = wl1273_fm_set_volume;

	if (pdata->children & WL1273_CODEC_CHILD) {
		cell = &core->cells[children];

		dev_dbg(&client->dev, "%s: Have codec.\n", __func__);
		cell->name = "wl1273-codec";
		cell->platform_data = &core;
		cell->pdata_size = sizeof(core);
		children++;
	}

	dev_dbg(&client->dev, "%s: number of children: %d.\n",
		__func__, children);

	r = devm_mfd_add_devices(&client->dev, -1, core->cells,
				 children, NULL, 0, NULL);
	if (r)
		goto err;

	return 0;

err:
	pdata->free_resources();

	dev_dbg(&client->dev, "%s\n", __func__);

	return r;
}

static struct i2c_driver wl1273_core_driver = {
	.driver = {
		.name = WL1273_FM_DRIVER_NAME,
	},
	.probe = wl1273_core_probe,
	.id_table = wl1273_driver_id_table,
};

static int __init wl1273_core_init(void)
{
	int r;

	r = i2c_add_driver(&wl1273_core_driver);
	if (r) {
		pr_err(WL1273_FM_DRIVER_NAME
		       ": driver registration failed\n");
		return r;
	}

	return r;
}

static void __exit wl1273_core_exit(void)
{
	i2c_del_driver(&wl1273_core_driver);
}
late_initcall(wl1273_core_init);
module_exit(wl1273_core_exit);

MODULE_AUTHOR("Matti Aaltonen <matti.j.aaltonen@nokia.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");