// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (C) 2016 Robert Jarzmik <[email protected]>
*/
#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/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 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", ®)) ||
!of_device_is_compatible(node, compat))
continue;
return 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) {
put_device(&codec->dev);
return ret;
}
return 0;
}
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 const 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 sysfs_emit(buf, "%08x", codec->vendor_id);
}
static 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, const struct device_driver *drv)
{
struct ac97_codec_device *adev = to_ac97_device(dev);
const 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 void 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_resume_and_get(dev);
if (ret < 0)
return;
adrv->remove(adev);
pm_runtime_put_noidle(dev);
ac97_put_disable_clk(adev);
pm_runtime_disable(dev);
}
const 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_DESCRIPTION("AC97 bus interface");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Robert Jarzmik <[email protected]>");
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