[linux.git] / sound / ac97 / bus.c

/*
 * Copyright (C) 2016 Robert Jarzmik <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/clk.h>
#include <linux/device.h>
#include <linux/idr.h>
#include <linux/list.h>
#include <linux/mutex.h>
#include <linux/of.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/slab.h>
#include <linux/sysfs.h>
#include <sound/ac97/codec.h>
#include <sound/ac97/controller.h>
#include <sound/ac97/regs.h>

#include "ac97_core.h"

/*
 * Protects ac97_controllers and each ac97_controller structure.
 */
static DEFINE_MUTEX(ac97_controllers_mutex);
static DEFINE_IDR(ac97_adapter_idr);
static LIST_HEAD(ac97_controllers);

static struct bus_type ac97_bus_type;

static inline struct ac97_controller*
to_ac97_controller(struct device *ac97_adapter)
{
	return container_of(ac97_adapter, struct ac97_controller, adap);
}

static int ac97_unbound_ctrl_write(struct ac97_controller *adrv, int slot,
		     unsigned short reg, unsigned short val)
{
	return -ENODEV;
}

static int ac97_unbound_ctrl_read(struct ac97_controller *adrv, int slot,
				  unsigned short reg)
{
	return -ENODEV;
}

static const struct ac97_controller_ops ac97_unbound_ctrl_ops = {
	.write = ac97_unbound_ctrl_write,
	.read = ac97_unbound_ctrl_read,
};

static struct ac97_controller ac97_unbound_ctrl = {
	.ops = &ac97_unbound_ctrl_ops,
};

static struct ac97_codec_device *
ac97_codec_find(struct ac97_controller *ac97_ctrl, unsigned int codec_num)
{
	if (codec_num >= AC97_BUS_MAX_CODECS)
		return ERR_PTR(-EINVAL);

	return ac97_ctrl->codecs[codec_num];
}

static struct device_node *
ac97_of_get_child_device(struct ac97_controller *ac97_ctrl, int idx,
			 unsigned int vendor_id)
{
	struct device_node *node;
	u32 reg;
	char compat[] = "ac97,0000,0000";

	snprintf(compat, sizeof(compat), "ac97,%04x,%04x",
		 vendor_id >> 16, vendor_id & 0xffff);

	for_each_child_of_node(ac97_ctrl->parent->of_node, node) {
		if ((idx != of_property_read_u32(node, "reg", &reg)) ||
		    !of_device_is_compatible(node, compat))
			continue;
		return of_node_get(node);
	}

	return NULL;
}

static void ac97_codec_release(struct device *dev)
{
	struct ac97_codec_device *adev;
	struct ac97_controller *ac97_ctrl;

	adev = to_ac97_device(dev);
	ac97_ctrl = adev->ac97_ctrl;
	ac97_ctrl->codecs[adev->num] = NULL;
	of_node_put(dev->of_node);
	kfree(adev);
}

static int ac97_codec_add(struct ac97_controller *ac97_ctrl, int idx,
		   unsigned int vendor_id)
{
	struct ac97_codec_device *codec;
	int ret;

	codec = kzalloc(sizeof(*codec), GFP_KERNEL);
	if (!codec)
		return -ENOMEM;
	ac97_ctrl->codecs[idx] = codec;
	codec->vendor_id = vendor_id;
	codec->dev.release = ac97_codec_release;
	codec->dev.bus = &ac97_bus_type;
	codec->dev.parent = &ac97_ctrl->adap;
	codec->num = idx;
	codec->ac97_ctrl = ac97_ctrl;

	device_initialize(&codec->dev);
	dev_set_name(&codec->dev, "%s:%u", dev_name(ac97_ctrl->parent), idx);
	codec->dev.of_node = ac97_of_get_child_device(ac97_ctrl, idx,
						      vendor_id);

	ret = device_add(&codec->dev);
	if (ret)
		goto err_free_codec;

	return 0;
err_free_codec:
	of_node_put(codec->dev.of_node);
	put_device(&codec->dev);
	kfree(codec);
	ac97_ctrl->codecs[idx] = NULL;

	return ret;
}

unsigned int snd_ac97_bus_scan_one(struct ac97_controller *adrv,
				   unsigned int codec_num)
{
	unsigned short vid1, vid2;
	int ret;

	ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID1);
	vid1 = (ret & 0xffff);
	if (ret < 0)
		return 0;

	ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID2);
	vid2 = (ret & 0xffff);
	if (ret < 0)
		return 0;

	dev_dbg(&adrv->adap, "%s(codec_num=%u): vendor_id=0x%08x\n",
		__func__, codec_num, AC97_ID(vid1, vid2));
	return AC97_ID(vid1, vid2);
}

static int ac97_bus_scan(struct ac97_controller *ac97_ctrl)
{
	int ret, i;
	unsigned int vendor_id;

	for (i = 0; i < AC97_BUS_MAX_CODECS; i++) {
		if (ac97_codec_find(ac97_ctrl, i))
			continue;
		if (!(ac97_ctrl->slots_available & BIT(i)))
			continue;
		vendor_id = snd_ac97_bus_scan_one(ac97_ctrl, i);
		if (!vendor_id)
			continue;

		ret = ac97_codec_add(ac97_ctrl, i, vendor_id);
		if (ret < 0)
			return ret;
	}
	return 0;
}

static int ac97_bus_reset(struct ac97_controller *ac97_ctrl)
{
	ac97_ctrl->ops->reset(ac97_ctrl);

	return 0;
}

/**
 * snd_ac97_codec_driver_register - register an AC97 codec driver
 * @dev: AC97 driver codec to register
 *
 * Register an AC97 codec driver to the ac97 bus driver, aka. the AC97 digital
 * controller.
 *
 * Returns 0 on success or error code
 */
int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv)
{
	drv->driver.bus = &ac97_bus_type;
	return driver_register(&drv->driver);
}
EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_register);

/**
 * snd_ac97_codec_driver_unregister - unregister an AC97 codec driver
 * @dev: AC97 codec driver to unregister
 *
 * Unregister a previously registered ac97 codec driver.
 */
void snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv)
{
	driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_unregister);

/**
 * snd_ac97_codec_get_platdata - get platform_data
 * @adev: the ac97 codec device
 *
 * For legacy platforms, in order to have platform_data in codec drivers
 * available, while ac97 device are auto-created upon probe, this retrieves the
 * platdata which was setup on ac97 controller registration.
 *
 * Returns the platform data pointer
 */
void *snd_ac97_codec_get_platdata(const struct ac97_codec_device *adev)
{
	struct ac97_controller *ac97_ctrl = adev->ac97_ctrl;

	return ac97_ctrl->codecs_pdata[adev->num];
}
EXPORT_SYMBOL_GPL(snd_ac97_codec_get_platdata);

static void ac97_ctrl_codecs_unregister(struct ac97_controller *ac97_ctrl)
{
	int i;

	for (i = 0; i < AC97_BUS_MAX_CODECS; i++)
		if (ac97_ctrl->codecs[i]) {
			ac97_ctrl->codecs[i]->ac97_ctrl = &ac97_unbound_ctrl;
			device_unregister(&ac97_ctrl->codecs[i]->dev);
		}
}

static ssize_t cold_reset_store(struct device *dev,
				struct device_attribute *attr, const char *buf,
				size_t len)
{
	struct ac97_controller *ac97_ctrl;

	mutex_lock(&ac97_controllers_mutex);
	ac97_ctrl = to_ac97_controller(dev);
	ac97_ctrl->ops->reset(ac97_ctrl);
	mutex_unlock(&ac97_controllers_mutex);
	return len;
}
static DEVICE_ATTR_WO(cold_reset);

static ssize_t warm_reset_store(struct device *dev,
				struct device_attribute *attr, const char *buf,
				size_t len)
{
	struct ac97_controller *ac97_ctrl;

	if (!dev)
		return -ENODEV;

	mutex_lock(&ac97_controllers_mutex);
	ac97_ctrl = to_ac97_controller(dev);
	ac97_ctrl->ops->warm_reset(ac97_ctrl);
	mutex_unlock(&ac97_controllers_mutex);
	return len;
}
static DEVICE_ATTR_WO(warm_reset);

static struct attribute *ac97_controller_device_attrs[] = {
	&dev_attr_cold_reset.attr,
	&dev_attr_warm_reset.attr,
	NULL
};

static struct attribute_group ac97_adapter_attr_group = {
	.name	= "ac97_operations",
	.attrs	= ac97_controller_device_attrs,
};

static const struct attribute_group *ac97_adapter_groups[] = {
	&ac97_adapter_attr_group,
	NULL,
};

static void ac97_del_adapter(struct ac97_controller *ac97_ctrl)
{
	mutex_lock(&ac97_controllers_mutex);
	ac97_ctrl_codecs_unregister(ac97_ctrl);
	list_del(&ac97_ctrl->controllers);
	mutex_unlock(&ac97_controllers_mutex);

	device_unregister(&ac97_ctrl->adap);
}

static void ac97_adapter_release(struct device *dev)
{
	struct ac97_controller *ac97_ctrl;

	ac97_ctrl = to_ac97_controller(dev);
	idr_remove(&ac97_adapter_idr, ac97_ctrl->nr);
	dev_dbg(&ac97_ctrl->adap, "adapter unregistered by %s\n",
		dev_name(ac97_ctrl->parent));
}

static const struct device_type ac97_adapter_type = {
	.groups		= ac97_adapter_groups,
	.release	= ac97_adapter_release,
};

static int ac97_add_adapter(struct ac97_controller *ac97_ctrl)
{
	int ret;

	mutex_lock(&ac97_controllers_mutex);
	ret = idr_alloc(&ac97_adapter_idr, ac97_ctrl, 0, 0, GFP_KERNEL);
	ac97_ctrl->nr = ret;
	if (ret >= 0) {
		dev_set_name(&ac97_ctrl->adap, "ac97-%d", ret);
		ac97_ctrl->adap.type = &ac97_adapter_type;
		ac97_ctrl->adap.parent = ac97_ctrl->parent;
		ret = device_register(&ac97_ctrl->adap);
		if (ret)
			put_device(&ac97_ctrl->adap);
	}
	if (!ret)
		list_add(&ac97_ctrl->controllers, &ac97_controllers);
	mutex_unlock(&ac97_controllers_mutex);

	if (!ret)
		dev_dbg(&ac97_ctrl->adap, "adapter registered by %s\n",
			dev_name(ac97_ctrl->parent));
	return ret;
}

/**
 * snd_ac97_controller_register - register an ac97 controller
 * @ops: the ac97 bus operations
 * @dev: the device providing the ac97 DC function
 * @slots_available: mask of the ac97 codecs that can be scanned and probed
 *                   bit0 => codec 0, bit1 => codec 1 ... bit 3 => codec 3
 *
 * Register a digital controller which can control up to 4 ac97 codecs. This is
 * the controller side of the AC97 AC-link, while the slave side are the codecs.
 *
 * Returns a valid controller upon success, negative pointer value upon error
 */
struct ac97_controller *snd_ac97_controller_register(
	const struct ac97_controller_ops *ops, struct device *dev,
	unsigned short slots_available, void **codecs_pdata)
{
	struct ac97_controller *ac97_ctrl;
	int ret, i;

	ac97_ctrl = kzalloc(sizeof(*ac97_ctrl), GFP_KERNEL);
	if (!ac97_ctrl)
		return ERR_PTR(-ENOMEM);

	for (i = 0; i < AC97_BUS_MAX_CODECS && codecs_pdata; i++)
		ac97_ctrl->codecs_pdata[i] = codecs_pdata[i];

	ac97_ctrl->ops = ops;
	ac97_ctrl->slots_available = slots_available;
	ac97_ctrl->parent = dev;
	ret = ac97_add_adapter(ac97_ctrl);

	if (ret)
		goto err;
	ac97_bus_reset(ac97_ctrl);
	ac97_bus_scan(ac97_ctrl);

	return ac97_ctrl;
err:
	kfree(ac97_ctrl);
	return ERR_PTR(ret);
}
EXPORT_SYMBOL_GPL(snd_ac97_controller_register);

/**
 * snd_ac97_controller_unregister - unregister an ac97 controller
 * @ac97_ctrl: the device previously provided to ac97_controller_register()
 *
 */
void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl)
{
	ac97_del_adapter(ac97_ctrl);
}
EXPORT_SYMBOL_GPL(snd_ac97_controller_unregister);

#ifdef CONFIG_PM
static int ac97_pm_runtime_suspend(struct device *dev)
{
	struct ac97_codec_device *codec = to_ac97_device(dev);
	int ret = pm_generic_runtime_suspend(dev);

	if (ret == 0 && dev->driver) {
		if (pm_runtime_is_irq_safe(dev))
			clk_disable(codec->clk);
		else
			clk_disable_unprepare(codec->clk);
	}

	return ret;
}

static int ac97_pm_runtime_resume(struct device *dev)
{
	struct ac97_codec_device *codec = to_ac97_device(dev);
	int ret;

	if (dev->driver) {
		if (pm_runtime_is_irq_safe(dev))
			ret = clk_enable(codec->clk);
		else
			ret = clk_prepare_enable(codec->clk);
		if (ret)
			return ret;
	}

	return pm_generic_runtime_resume(dev);
}
#endif /* CONFIG_PM */

static const struct dev_pm_ops ac97_pm = {
	.suspend	= pm_generic_suspend,
	.resume		= pm_generic_resume,
	.freeze		= pm_generic_freeze,
	.thaw		= pm_generic_thaw,
	.poweroff	= pm_generic_poweroff,
	.restore	= pm_generic_restore,
	SET_RUNTIME_PM_OPS(
		ac97_pm_runtime_suspend,
		ac97_pm_runtime_resume,
		NULL)
};

static int ac97_get_enable_clk(struct ac97_codec_device *adev)
{
	int ret;

	adev->clk = clk_get(&adev->dev, "ac97_clk");
	if (IS_ERR(adev->clk))
		return PTR_ERR(adev->clk);

	ret = clk_prepare_enable(adev->clk);
	if (ret)
		clk_put(adev->clk);

	return ret;
}

static void ac97_put_disable_clk(struct ac97_codec_device *adev)
{
	clk_disable_unprepare(adev->clk);
	clk_put(adev->clk);
}

static ssize_t vendor_id_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct ac97_codec_device *codec = to_ac97_device(dev);

	return sprintf(buf, "%08x", codec->vendor_id);
}
DEVICE_ATTR_RO(vendor_id);

static struct attribute *ac97_dev_attrs[] = {
	&dev_attr_vendor_id.attr,
	NULL,
};
ATTRIBUTE_GROUPS(ac97_dev);

static int ac97_bus_match(struct device *dev, struct device_driver *drv)
{
	struct ac97_codec_device *adev = to_ac97_device(dev);
	struct ac97_codec_driver *adrv = to_ac97_driver(drv);
	const struct ac97_id *id = adrv->id_table;
	int i = 0;

	if (adev->vendor_id == 0x0 || adev->vendor_id == 0xffffffff)
		return false;

	do {
		if (ac97_ids_match(id[i].id, adev->vendor_id, id[i].mask))
			return true;
	} while (id[i++].id);

	return false;
}

static int ac97_bus_probe(struct device *dev)
{
	struct ac97_codec_device *adev = to_ac97_device(dev);
	struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver);
	int ret;

	ret = ac97_get_enable_clk(adev);
	if (ret)
		return ret;

	pm_runtime_get_noresume(dev);
	pm_runtime_set_active(dev);
	pm_runtime_enable(dev);

	ret = adrv->probe(adev);
	if (ret == 0)
		return 0;

	pm_runtime_disable(dev);
	pm_runtime_set_suspended(dev);
	pm_runtime_put_noidle(dev);
	ac97_put_disable_clk(adev);

	return ret;
}

static int ac97_bus_remove(struct device *dev)
{
	struct ac97_codec_device *adev = to_ac97_device(dev);
	struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver);
	int ret;

	ret = pm_runtime_get_sync(dev);
	if (ret < 0)
		return ret;

	ret = adrv->remove(adev);
	pm_runtime_put_noidle(dev);
	if (ret == 0)
		ac97_put_disable_clk(adev);

	pm_runtime_disable(dev);

	return ret;
}

static struct bus_type ac97_bus_type = {
	.name		= "ac97bus",
	.dev_groups	= ac97_dev_groups,
	.match		= ac97_bus_match,
	.pm		= &ac97_pm,
	.probe		= ac97_bus_probe,
	.remove		= ac97_bus_remove,
};

static int __init ac97_bus_init(void)
{
	return bus_register(&ac97_bus_type);
}
subsys_initcall(ac97_bus_init);

static void __exit ac97_bus_exit(void)
{
	bus_unregister(&ac97_bus_type);
}
module_exit(ac97_bus_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Robert Jarzmik <[email protected]>");
Commit	Line	Data
74426fbf RJ	1	/*
	2	* Copyright (C) 2016 Robert Jarzmik <[email protected]>
	3	*
	4	* This program is free software; you can redistribute it and/or modify
	5	* it under the terms of the GNU General Public License version 2 as
	6	* published by the Free Software Foundation.
	7	*/
	8
	9	#include <linux/module.h>
	10	#include <linux/bitops.h>
	11	#include <linux/clk.h>
	12	#include <linux/device.h>
	13	#include <linux/idr.h>
	14	#include <linux/list.h>
	15	#include <linux/mutex.h>
2225a3e6	16	#include <linux/of.h>
74426fbf RJ	17	#include <linux/pm.h>
	18	#include <linux/pm_runtime.h>
	19	#include <linux/slab.h>
	20	#include <linux/sysfs.h>
	21	#include <sound/ac97/codec.h>
	22	#include <sound/ac97/controller.h>
	23	#include <sound/ac97/regs.h>
	24
	25	#include "ac97_core.h"
	26
	27	/*
	28	* Protects ac97_controllers and each ac97_controller structure.
	29	*/
	30	static DEFINE_MUTEX(ac97_controllers_mutex);
	31	static DEFINE_IDR(ac97_adapter_idr);
	32	static LIST_HEAD(ac97_controllers);
	33
	34	static struct bus_type ac97_bus_type;
	35
	36	static inline struct ac97_controller*
	37	to_ac97_controller(struct device *ac97_adapter)
	38	{
	39	return container_of(ac97_adapter, struct ac97_controller, adap);
	40	}
	41
	42	static int ac97_unbound_ctrl_write(struct ac97_controller *adrv, int slot,
	43	unsigned short reg, unsigned short val)
	44	{
	45	return -ENODEV;
	46	}
	47
	48	static int ac97_unbound_ctrl_read(struct ac97_controller *adrv, int slot,
	49	unsigned short reg)
	50	{
	51	return -ENODEV;
	52	}
	53
	54	static const struct ac97_controller_ops ac97_unbound_ctrl_ops = {
	55	.write = ac97_unbound_ctrl_write,
	56	.read = ac97_unbound_ctrl_read,
	57	};
	58
	59	static struct ac97_controller ac97_unbound_ctrl = {
	60	.ops = &ac97_unbound_ctrl_ops,
	61	};
	62
	63	static struct ac97_codec_device *
	64	ac97_codec_find(struct ac97_controller *ac97_ctrl, unsigned int codec_num)
	65	{
	66	if (codec_num >= AC97_BUS_MAX_CODECS)
	67	return ERR_PTR(-EINVAL);
	68
	69	return ac97_ctrl->codecs[codec_num];
	70	}
	71
2225a3e6 RJ	72	static struct device_node *
	73	ac97_of_get_child_device(struct ac97_controller *ac97_ctrl, int idx,
	74	unsigned int vendor_id)
	75	{
	76	struct device_node *node;
	77	u32 reg;
	78	char compat[] = "ac97,0000,0000";
	79
	80	snprintf(compat, sizeof(compat), "ac97,%04x,%04x",
	81	vendor_id >> 16, vendor_id & 0xffff);
	82
	83	for_each_child_of_node(ac97_ctrl->parent->of_node, node) {
	84	if ((idx != of_property_read_u32(node, "reg", &reg)) \|\|
	85	!of_device_is_compatible(node, compat))
	86	continue;
	87	return of_node_get(node);
	88	}
	89
	90	return NULL;
	91	}
	92
74426fbf RJ	93	static void ac97_codec_release(struct device *dev)
	94	{
	95	struct ac97_codec_device *adev;
	96	struct ac97_controller *ac97_ctrl;
	97
	98	adev = to_ac97_device(dev);
	99	ac97_ctrl = adev->ac97_ctrl;
	100	ac97_ctrl->codecs[adev->num] = NULL;
2225a3e6	101	of_node_put(dev->of_node);
74426fbf RJ	102	kfree(adev);
	103	}
	104
	105	static int ac97_codec_add(struct ac97_controller *ac97_ctrl, int idx,
	106	unsigned int vendor_id)
	107	{
	108	struct ac97_codec_device *codec;
	109	int ret;
	110
	111	codec = kzalloc(sizeof(*codec), GFP_KERNEL);
	112	if (!codec)
	113	return -ENOMEM;
	114	ac97_ctrl->codecs[idx] = codec;
	115	codec->vendor_id = vendor_id;
	116	codec->dev.release = ac97_codec_release;
	117	codec->dev.bus = &ac97_bus_type;
	118	codec->dev.parent = &ac97_ctrl->adap;
	119	codec->num = idx;
	120	codec->ac97_ctrl = ac97_ctrl;
	121
	122	device_initialize(&codec->dev);
	123	dev_set_name(&codec->dev, "%s:%u", dev_name(ac97_ctrl->parent), idx);
2225a3e6 RJ	124	codec->dev.of_node = ac97_of_get_child_device(ac97_ctrl, idx,
2225a3e6 RJ	125	vendor_id);
74426fbf RJ	126
	127	ret = device_add(&codec->dev);
	128	if (ret)
	129	goto err_free_codec;
	130
	131	return 0;
	132	err_free_codec:
2225a3e6	133	of_node_put(codec->dev.of_node);
74426fbf RJ	134	put_device(&codec->dev);
	135	kfree(codec);
	136	ac97_ctrl->codecs[idx] = NULL;
	137
	138	return ret;
	139	}
	140
	141	unsigned int snd_ac97_bus_scan_one(struct ac97_controller *adrv,
	142	unsigned int codec_num)
	143	{
	144	unsigned short vid1, vid2;
	145	int ret;
	146
	147	ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID1);
	148	vid1 = (ret & 0xffff);
	149	if (ret < 0)
	150	return 0;
	151
	152	ret = adrv->ops->read(adrv, codec_num, AC97_VENDOR_ID2);
	153	vid2 = (ret & 0xffff);
	154	if (ret < 0)
	155	return 0;
	156
	157	dev_dbg(&adrv->adap, "%s(codec_num=%u): vendor_id=0x%08x\n",
	158	__func__, codec_num, AC97_ID(vid1, vid2));
	159	return AC97_ID(vid1, vid2);
	160	}
	161
	162	static int ac97_bus_scan(struct ac97_controller *ac97_ctrl)
	163	{
	164	int ret, i;
	165	unsigned int vendor_id;
	166
	167	for (i = 0; i < AC97_BUS_MAX_CODECS; i++) {
	168	if (ac97_codec_find(ac97_ctrl, i))
	169	continue;
	170	if (!(ac97_ctrl->slots_available & BIT(i)))
	171	continue;
	172	vendor_id = snd_ac97_bus_scan_one(ac97_ctrl, i);
	173	if (!vendor_id)
	174	continue;
	175
	176	ret = ac97_codec_add(ac97_ctrl, i, vendor_id);
	177	if (ret < 0)
	178	return ret;
	179	}
	180	return 0;
	181	}
	182
	183	static int ac97_bus_reset(struct ac97_controller *ac97_ctrl)
	184	{
	185	ac97_ctrl->ops->reset(ac97_ctrl);
	186
	187	return 0;
	188	}
	189
	190	/**
	191	* snd_ac97_codec_driver_register - register an AC97 codec driver
	192	* @dev: AC97 driver codec to register
	193	*
	194	* Register an AC97 codec driver to the ac97 bus driver, aka. the AC97 digital
	195	* controller.
	196	*
	197	* Returns 0 on success or error code
198	*/
199	int snd_ac97_codec_driver_register(struct ac97_codec_driver *drv)
200	{
201	drv->driver.bus = &ac97_bus_type;
202	return driver_register(&drv->driver);
203	}
204	EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_register);
205
206	/**
207	* snd_ac97_codec_driver_unregister - unregister an AC97 codec driver
208	* @dev: AC97 codec driver to unregister
209	*
210	* Unregister a previously registered ac97 codec driver.
211	*/
212	void snd_ac97_codec_driver_unregister(struct ac97_codec_driver *drv)
213	{
214	driver_unregister(&drv->driver);
215	}
216	EXPORT_SYMBOL_GPL(snd_ac97_codec_driver_unregister);
217
218	/**
219	* snd_ac97_codec_get_platdata - get platform_data
220	* @adev: the ac97 codec device
221	*
222	* For legacy platforms, in order to have platform_data in codec drivers
223	* available, while ac97 device are auto-created upon probe, this retrieves the
224	* platdata which was setup on ac97 controller registration.
225	*
226	* Returns the platform data pointer
227	*/
228	void snd_ac97_codec_get_platdata(const struct ac97_codec_device adev)
229	{
230	struct ac97_controller *ac97_ctrl = adev->ac97_ctrl;
231
232	return ac97_ctrl->codecs_pdata[adev->num];
233	}
234	EXPORT_SYMBOL_GPL(snd_ac97_codec_get_platdata);
235
236	static void ac97_ctrl_codecs_unregister(struct ac97_controller *ac97_ctrl)
237	{
238	int i;
239
240	for (i = 0; i < AC97_BUS_MAX_CODECS; i++)
241	if (ac97_ctrl->codecs[i]) {
242	ac97_ctrl->codecs[i]->ac97_ctrl = &ac97_unbound_ctrl;
243	device_unregister(&ac97_ctrl->codecs[i]->dev);
244	}
245	}
246
247	static ssize_t cold_reset_store(struct device *dev,
248	struct device_attribute attr, const char buf,
249	size_t len)
250	{
251	struct ac97_controller *ac97_ctrl;
252
253	mutex_lock(&ac97_controllers_mutex);
254	ac97_ctrl = to_ac97_controller(dev);
255	ac97_ctrl->ops->reset(ac97_ctrl);
256	mutex_unlock(&ac97_controllers_mutex);
257	return len;
258	}
259	static DEVICE_ATTR_WO(cold_reset);
260
261	static ssize_t warm_reset_store(struct device *dev,
262	struct device_attribute attr, const char buf,
263	size_t len)
264	{
265	struct ac97_controller *ac97_ctrl;
266
267	if (!dev)
268	return -ENODEV;
269
270	mutex_lock(&ac97_controllers_mutex);
271	ac97_ctrl = to_ac97_controller(dev);
272	ac97_ctrl->ops->warm_reset(ac97_ctrl);
273	mutex_unlock(&ac97_controllers_mutex);
274	return len;
275	}
276	static DEVICE_ATTR_WO(warm_reset);
277
278	static struct attribute *ac97_controller_device_attrs[] = {
279	&dev_attr_cold_reset.attr,
280	&dev_attr_warm_reset.attr,
281	NULL
282	};
283
284	static struct attribute_group ac97_adapter_attr_group = {
285	.name = "ac97_operations",
286	.attrs = ac97_controller_device_attrs,
287	};
288
289	static const struct attribute_group *ac97_adapter_groups[] = {
290	&ac97_adapter_attr_group,
291	NULL,
292	};
293
294	static void ac97_del_adapter(struct ac97_controller *ac97_ctrl)
295	{
296	mutex_lock(&ac97_controllers_mutex);
297	ac97_ctrl_codecs_unregister(ac97_ctrl);
298	list_del(&ac97_ctrl->controllers);
299	mutex_unlock(&ac97_controllers_mutex);
300
301	device_unregister(&ac97_ctrl->adap);
302	}
303
304	static void ac97_adapter_release(struct device *dev)
305	{
306	struct ac97_controller *ac97_ctrl;
307
308	ac97_ctrl = to_ac97_controller(dev);
309	idr_remove(&ac97_adapter_idr, ac97_ctrl->nr);
310	dev_dbg(&ac97_ctrl->adap, "adapter unregistered by %s\n",
311	dev_name(ac97_ctrl->parent));
312	}
313
314	static const struct device_type ac97_adapter_type = {
315	.groups = ac97_adapter_groups,
316	.release = ac97_adapter_release,
317	};
318
319	static int ac97_add_adapter(struct ac97_controller *ac97_ctrl)
320	{
321	int ret;
322
323	mutex_lock(&ac97_controllers_mutex);
324	ret = idr_alloc(&ac97_adapter_idr, ac97_ctrl, 0, 0, GFP_KERNEL);
325	ac97_ctrl->nr = ret;
326	if (ret >= 0) {
327	dev_set_name(&ac97_ctrl->adap, "ac97-%d", ret);
328	ac97_ctrl->adap.type = &ac97_adapter_type;
329	ac97_ctrl->adap.parent = ac97_ctrl->parent;
330	ret = device_register(&ac97_ctrl->adap);
331	if (ret)
332	put_device(&ac97_ctrl->adap);
333	}
334	if (!ret)
335	list_add(&ac97_ctrl->controllers, &ac97_controllers);
336	mutex_unlock(&ac97_controllers_mutex);
337
338	if (!ret)
339	dev_dbg(&ac97_ctrl->adap, "adapter registered by %s\n",
340	dev_name(ac97_ctrl->parent));
341	return ret;
342	}
343
344	/**
345	* snd_ac97_controller_register - register an ac97 controller
346	* @ops: the ac97 bus operations
347	* @dev: the device providing the ac97 DC function
348	* @slots_available: mask of the ac97 codecs that can be scanned and probed
349	* bit0 => codec 0, bit1 => codec 1 ... bit 3 => codec 3
350	*
351	* Register a digital controller which can control up to 4 ac97 codecs. This is
352	* the controller side of the AC97 AC-link, while the slave side are the codecs.
353	*
354	* Returns a valid controller upon success, negative pointer value upon error
355	*/
356	struct ac97_controller *snd_ac97_controller_register(
357	const struct ac97_controller_ops ops, struct device dev,
358	unsigned short slots_available, void **codecs_pdata)
359	{
360	struct ac97_controller *ac97_ctrl;
361	int ret, i;
362
363	ac97_ctrl = kzalloc(sizeof(*ac97_ctrl), GFP_KERNEL);
364	if (!ac97_ctrl)
365	return ERR_PTR(-ENOMEM);
366
367	for (i = 0; i < AC97_BUS_MAX_CODECS && codecs_pdata; i++)
368	ac97_ctrl->codecs_pdata[i] = codecs_pdata[i];
369
370	ac97_ctrl->ops = ops;
371	ac97_ctrl->slots_available = slots_available;
372	ac97_ctrl->parent = dev;
373	ret = ac97_add_adapter(ac97_ctrl);
374
375	if (ret)
376	goto err;
377	ac97_bus_reset(ac97_ctrl);
378	ac97_bus_scan(ac97_ctrl);
379
380	return ac97_ctrl;
381	err:
382	kfree(ac97_ctrl);
383	return ERR_PTR(ret);
384	}
385	EXPORT_SYMBOL_GPL(snd_ac97_controller_register);
386
387	/**
388	* snd_ac97_controller_unregister - unregister an ac97 controller
389	* @ac97_ctrl: the device previously provided to ac97_controller_register()
390	*
391	*/
392	void snd_ac97_controller_unregister(struct ac97_controller *ac97_ctrl)
393	{
394	ac97_del_adapter(ac97_ctrl);
395	}
396	EXPORT_SYMBOL_GPL(snd_ac97_controller_unregister);
397
398	#ifdef CONFIG_PM
399	static int ac97_pm_runtime_suspend(struct device *dev)
400	{
401	struct ac97_codec_device *codec = to_ac97_device(dev);
402	int ret = pm_generic_runtime_suspend(dev);
403
404	if (ret == 0 && dev->driver) {
405	if (pm_runtime_is_irq_safe(dev))
406	clk_disable(codec->clk);
407	else
408	clk_disable_unprepare(codec->clk);
409	}
410
411	return ret;
412	}
413
414	static int ac97_pm_runtime_resume(struct device *dev)
415	{
416	struct ac97_codec_device *codec = to_ac97_device(dev);
417	int ret;
418
419	if (dev->driver) {
420	if (pm_runtime_is_irq_safe(dev))
421	ret = clk_enable(codec->clk);
422	else
423	ret = clk_prepare_enable(codec->clk);
424	if (ret)
425	return ret;
426	}
427
428	return pm_generic_runtime_resume(dev);
429	}
430	#endif /* CONFIG_PM */
431
432	static const struct dev_pm_ops ac97_pm = {
433	.suspend = pm_generic_suspend,
434	.resume = pm_generic_resume,
435	.freeze = pm_generic_freeze,
436	.thaw = pm_generic_thaw,
437	.poweroff = pm_generic_poweroff,
438	.restore = pm_generic_restore,
439	SET_RUNTIME_PM_OPS(
440	ac97_pm_runtime_suspend,
441	ac97_pm_runtime_resume,
442	NULL)
443	};
444
445	static int ac97_get_enable_clk(struct ac97_codec_device *adev)
446	{
447	int ret;
448
449	adev->clk = clk_get(&adev->dev, "ac97_clk");
450	if (IS_ERR(adev->clk))
451	return PTR_ERR(adev->clk);
452
453	ret = clk_prepare_enable(adev->clk);
454	if (ret)
455	clk_put(adev->clk);
456
457	return ret;
458	}
459
460	static void ac97_put_disable_clk(struct ac97_codec_device *adev)
461	{
462	clk_disable_unprepare(adev->clk);
463	clk_put(adev->clk);
464	}
465
466	static ssize_t vendor_id_show(struct device *dev,
467	struct device_attribute attr, char buf)
468	{
469	struct ac97_codec_device *codec = to_ac97_device(dev);
470
471	return sprintf(buf, "%08x", codec->vendor_id);
472	}
473	DEVICE_ATTR_RO(vendor_id);
474
475	static struct attribute *ac97_dev_attrs[] = {
476	&dev_attr_vendor_id.attr,
477	NULL,
478	};
479	ATTRIBUTE_GROUPS(ac97_dev);
480
481	static int ac97_bus_match(struct device dev, struct device_driver drv)
482	{
483	struct ac97_codec_device *adev = to_ac97_device(dev);
484	struct ac97_codec_driver *adrv = to_ac97_driver(drv);
485	const struct ac97_id *id = adrv->id_table;
486	int i = 0;
487
488	if (adev->vendor_id == 0x0 \|\| adev->vendor_id == 0xffffffff)
489	return false;
490
491	do {
492	if (ac97_ids_match(id[i].id, adev->vendor_id, id[i].mask))
493	return true;
494	} while (id[i++].id);
495
496	return false;
497	}
498
499	static int ac97_bus_probe(struct device *dev)
500	{
501	struct ac97_codec_device *adev = to_ac97_device(dev);
502	struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver);
503	int ret;
504
505	ret = ac97_get_enable_clk(adev);
506	if (ret)
507	return ret;
508
509	pm_runtime_get_noresume(dev);
510	pm_runtime_set_active(dev);
511	pm_runtime_enable(dev);
512
513	ret = adrv->probe(adev);
514	if (ret == 0)
515	return 0;
516
517	pm_runtime_disable(dev);
518	pm_runtime_set_suspended(dev);
519	pm_runtime_put_noidle(dev);
520	ac97_put_disable_clk(adev);
521
522	return ret;
523	}
524
525	static int ac97_bus_remove(struct device *dev)
526	{
527	struct ac97_codec_device *adev = to_ac97_device(dev);
528	struct ac97_codec_driver *adrv = to_ac97_driver(dev->driver);
529	int ret;
530
531	ret = pm_runtime_get_sync(dev);
d15ec0b4	532	if (ret < 0)
74426fbf RJ	533	return ret;
	534
	535	ret = adrv->remove(adev);
	536	pm_runtime_put_noidle(dev);
	537	if (ret == 0)
	538	ac97_put_disable_clk(adev);
	539
250ea7c5 LY	540	pm_runtime_disable(dev);
250ea7c5 LY	541
74426fbf RJ	542	return ret;
	543	}
	544
	545	static struct bus_type ac97_bus_type = {
	546	.name = "ac97bus",
	547	.dev_groups = ac97_dev_groups,
	548	.match = ac97_bus_match,
	549	.pm = &ac97_pm,
	550	.probe = ac97_bus_probe,
	551	.remove = ac97_bus_remove,
	552	};
	553
	554	static int __init ac97_bus_init(void)
	555	{
	556	return bus_register(&ac97_bus_type);
	557	}
	558	subsys_initcall(ac97_bus_init);
	559
	560	static void __exit ac97_bus_exit(void)
	561	{
	562	bus_unregister(&ac97_bus_type);
	563	}
	564	module_exit(ac97_bus_exit);
	565
	566	MODULE_LICENSE("GPL");
	567	MODULE_AUTHOR("Robert Jarzmik <[email protected]>");