linux/sound/hda/ext/hdac_ext_bus.c
Takashi Iwai 19abfefd4c ALSA: hda: Direct MMIO accesses
HD-audio drivers access to the mmio registers indirectly via the
corresponding bus->io_ops callbacks.  This is because some platform
(notably Tegra SoC) requires the word-aligned access.  But it's rather
a rare case, and other platforms suffer from the penalties by indirect
calls unnecessarily.

This patch is an attempt to optimize and cleanup for this situation.
Now the special aligned access is used only when a new kconfig
CONFIG_SND_HDA_ALIGNED_MMIO is set.  And the HD-audio core itself
provides the aligned MMIO access helpers instead of the driver side.
If Kconfig isn't set (as default), the standard helpers like readl()
or writel() are used directly.

A couple of places in ASoC Intel drivers have the access via io_ops
reg_writel(), and they are replaced with the direct writel() calls.

And now with this patch, the whole bus->io_ops becomes empty, so it's
dropped completely.  The bus initialization functions are changed
accordingly as well to drop the whole bus->io_ops.

Reviewed-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
2019-08-08 16:36:18 +02:00

194 lines
4.7 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* hdac-ext-bus.c - HD-audio extended core bus functions.
*
* Copyright (C) 2014-2015 Intel Corp
* Author: Jeeja KP <jeeja.kp@intel.com>
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*
* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
*/
#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");
/**
* 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
* default ops
*
* Returns 0 if successful, or a negative error code.
*/
int snd_hdac_ext_bus_init(struct hdac_bus *bus, struct device *dev,
const struct hdac_bus_ops *ops,
const struct hdac_ext_bus_ops *ext_ops)
{
int ret;
ret = snd_hdac_bus_init(bus, dev, ops);
if (ret < 0)
return ret;
bus->ext_ops = ext_ops;
/* FIXME:
* Currently only one bus is supported, if there is device with more
* buses, bus->idx should be greater than 0, but there needs to be a
* reliable way to always assign same number.
*/
bus->idx = 0;
bus->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_bus *bus)
{
snd_hdac_bus_exit(bus);
WARN_ON(!list_empty(&bus->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_bus *bus, int addr,
struct hdac_device *hdev)
{
char name[15];
int ret;
hdev->bus = bus;
snprintf(name, sizeof(name), "ehdaudio%dD%d", bus->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)
{
snd_hdac_device_exit(hdev);
}
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_bus *bus)
{
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, &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_driver *get_hdrv(struct device *dev)
{
struct hdac_driver *hdrv = drv_to_hdac_driver(dev->driver);
return hdrv;
}
static inline struct hdac_device *get_hdev(struct device *dev)
{
struct hdac_device *hdev = dev_to_hdac_dev(dev);
return hdev;
}
static int hda_ext_drv_probe(struct device *dev)
{
return (get_hdrv(dev))->probe(get_hdev(dev));
}
static int hdac_ext_drv_remove(struct device *dev)
{
return (get_hdrv(dev))->remove(get_hdev(dev));
}
static void hdac_ext_drv_shutdown(struct device *dev)
{
return (get_hdrv(dev))->shutdown(get_hdev(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_driver *drv)
{
drv->type = HDA_DEV_ASOC;
drv->driver.bus = &snd_hda_bus_type;
/* we use default match */
if (drv->probe)
drv->driver.probe = hda_ext_drv_probe;
if (drv->remove)
drv->driver.remove = hdac_ext_drv_remove;
if (drv->shutdown)
drv->driver.shutdown = hdac_ext_drv_shutdown;
return driver_register(&drv->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_driver *drv)
{
driver_unregister(&drv->driver);
}
EXPORT_SYMBOL_GPL(snd_hda_ext_driver_unregister);