linux/sound/hda/ext/hdac_ext_bus.c
Vinod Koul 4446085d21 ALSA: hdac: add link pm and ref counting
The HDA links can be switched off when not is use, similarly
command DMA can be stopped as well. This calls for a reference
counting mechanism on the link by it's users to manage the link
power. The DMA can be turned off when all links are off

For this we add two APIs
	snd_hdac_ext_bus_link_get
	snd_hdac_ext_bus_link_put

They help users to turn up/down link and manage the DMA as well

Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
2016-05-13 11:43:00 +01:00

269 lines
6.7 KiB
C

/*
* hdac-ext-bus.c - HD-audio extended core bus functions.
*
* Copyright (C) 2014-2015 Intel Corp
* Author: Jeeja KP <jeeja.kp@intel.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; version 2 of the License.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <sound/hdaudio_ext.h>
MODULE_DESCRIPTION("HDA extended core");
MODULE_LICENSE("GPL v2");
static void hdac_ext_writel(u32 value, u32 __iomem *addr)
{
writel(value, addr);
}
static u32 hdac_ext_readl(u32 __iomem *addr)
{
return readl(addr);
}
static void hdac_ext_writew(u16 value, u16 __iomem *addr)
{
writew(value, addr);
}
static u16 hdac_ext_readw(u16 __iomem *addr)
{
return readw(addr);
}
static void hdac_ext_writeb(u8 value, u8 __iomem *addr)
{
writeb(value, addr);
}
static u8 hdac_ext_readb(u8 __iomem *addr)
{
return readb(addr);
}
static int hdac_ext_dma_alloc_pages(struct hdac_bus *bus, int type,
size_t size, struct snd_dma_buffer *buf)
{
return snd_dma_alloc_pages(type, bus->dev, size, buf);
}
static void hdac_ext_dma_free_pages(struct hdac_bus *bus, struct snd_dma_buffer *buf)
{
snd_dma_free_pages(buf);
}
static const struct hdac_io_ops hdac_ext_default_io = {
.reg_writel = hdac_ext_writel,
.reg_readl = hdac_ext_readl,
.reg_writew = hdac_ext_writew,
.reg_readw = hdac_ext_readw,
.reg_writeb = hdac_ext_writeb,
.reg_readb = hdac_ext_readb,
.dma_alloc_pages = hdac_ext_dma_alloc_pages,
.dma_free_pages = hdac_ext_dma_free_pages,
};
/**
* snd_hdac_ext_bus_init - initialize a HD-audio extended bus
* @ebus: the pointer to extended bus object
* @dev: device pointer
* @ops: bus verb operators
* @io_ops: lowlevel I/O operators, can be NULL. If NULL core will use
* default ops
*
* Returns 0 if successful, or a negative error code.
*/
int snd_hdac_ext_bus_init(struct hdac_ext_bus *ebus, struct device *dev,
const struct hdac_bus_ops *ops,
const struct hdac_io_ops *io_ops)
{
int ret;
static int idx;
/* check if io ops are provided, if not load the defaults */
if (io_ops == NULL)
io_ops = &hdac_ext_default_io;
ret = snd_hdac_bus_init(&ebus->bus, dev, ops, io_ops);
if (ret < 0)
return ret;
INIT_LIST_HEAD(&ebus->hlink_list);
ebus->idx = idx++;
mutex_init(&ebus->lock);
ebus->cmd_dma_state = true;
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_init);
/**
* snd_hdac_ext_bus_exit - clean up a HD-audio extended bus
* @ebus: the pointer to extended bus object
*/
void snd_hdac_ext_bus_exit(struct hdac_ext_bus *ebus)
{
snd_hdac_bus_exit(&ebus->bus);
WARN_ON(!list_empty(&ebus->hlink_list));
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_exit);
static void default_release(struct device *dev)
{
snd_hdac_ext_bus_device_exit(container_of(dev, struct hdac_device, dev));
}
/**
* snd_hdac_ext_bus_device_init - initialize the HDA extended codec base device
* @ebus: hdac extended bus to attach to
* @addr: codec address
*
* Returns zero for success or a negative error code.
*/
int snd_hdac_ext_bus_device_init(struct hdac_ext_bus *ebus, int addr)
{
struct hdac_ext_device *edev;
struct hdac_device *hdev = NULL;
struct hdac_bus *bus = ebus_to_hbus(ebus);
char name[15];
int ret;
edev = kzalloc(sizeof(*edev), GFP_KERNEL);
if (!edev)
return -ENOMEM;
hdev = &edev->hdac;
snprintf(name, sizeof(name), "ehdaudio%dD%d", ebus->idx, addr);
ret = snd_hdac_device_init(hdev, bus, name, addr);
if (ret < 0) {
dev_err(bus->dev, "device init failed for hdac device\n");
return ret;
}
hdev->type = HDA_DEV_ASOC;
hdev->dev.release = default_release;
ret = snd_hdac_device_register(hdev);
if (ret) {
dev_err(bus->dev, "failed to register hdac device\n");
snd_hdac_ext_bus_device_exit(hdev);
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_device_init);
/**
* snd_hdac_ext_bus_device_exit - clean up a HD-audio extended codec base device
* @hdev: hdac device to clean up
*/
void snd_hdac_ext_bus_device_exit(struct hdac_device *hdev)
{
struct hdac_ext_device *edev = to_ehdac_device(hdev);
snd_hdac_device_exit(hdev);
kfree(edev);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_device_exit);
/**
* snd_hdac_ext_bus_device_remove - remove HD-audio extended codec base devices
*
* @ebus: HD-audio extended bus
*/
void snd_hdac_ext_bus_device_remove(struct hdac_ext_bus *ebus)
{
struct hdac_device *codec, *__codec;
/*
* we need to remove all the codec devices objects created in the
* snd_hdac_ext_bus_device_init
*/
list_for_each_entry_safe(codec, __codec, &ebus->bus.codec_list, list) {
snd_hdac_device_unregister(codec);
put_device(&codec->dev);
}
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_device_remove);
#define dev_to_hdac(dev) (container_of((dev), \
struct hdac_device, dev))
static inline struct hdac_ext_driver *get_edrv(struct device *dev)
{
struct hdac_driver *hdrv = drv_to_hdac_driver(dev->driver);
struct hdac_ext_driver *edrv = to_ehdac_driver(hdrv);
return edrv;
}
static inline struct hdac_ext_device *get_edev(struct device *dev)
{
struct hdac_device *hdev = dev_to_hdac_dev(dev);
struct hdac_ext_device *edev = to_ehdac_device(hdev);
return edev;
}
static int hda_ext_drv_probe(struct device *dev)
{
return (get_edrv(dev))->probe(get_edev(dev));
}
static int hdac_ext_drv_remove(struct device *dev)
{
return (get_edrv(dev))->remove(get_edev(dev));
}
static void hdac_ext_drv_shutdown(struct device *dev)
{
return (get_edrv(dev))->shutdown(get_edev(dev));
}
/**
* snd_hda_ext_driver_register - register a driver for ext hda devices
*
* @drv: ext hda driver structure
*/
int snd_hda_ext_driver_register(struct hdac_ext_driver *drv)
{
drv->hdac.type = HDA_DEV_ASOC;
drv->hdac.driver.bus = &snd_hda_bus_type;
/* we use default match */
if (drv->probe)
drv->hdac.driver.probe = hda_ext_drv_probe;
if (drv->remove)
drv->hdac.driver.remove = hdac_ext_drv_remove;
if (drv->shutdown)
drv->hdac.driver.shutdown = hdac_ext_drv_shutdown;
return driver_register(&drv->hdac.driver);
}
EXPORT_SYMBOL_GPL(snd_hda_ext_driver_register);
/**
* snd_hda_ext_driver_unregister - unregister a driver for ext hda devices
*
* @drv: ext hda driver structure
*/
void snd_hda_ext_driver_unregister(struct hdac_ext_driver *drv)
{
driver_unregister(&drv->hdac.driver);
}
EXPORT_SYMBOL_GPL(snd_hda_ext_driver_unregister);