linux-stable/sound/hda/ext/hdac_ext_controller.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

395 lines
9.9 KiB
C

/*
* hdac-ext-controller.c - HD-audio extended controller 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/delay.h>
#include <linux/slab.h>
#include <sound/hda_register.h>
#include <sound/hdaudio_ext.h>
/*
* maximum HDAC capablities we should parse to avoid endless looping:
* currently we have 4 extended caps, so this is future proof for now.
* extend when this limit is seen meeting in real HW
*/
#define HDAC_MAX_CAPS 10
/**
* snd_hdac_ext_bus_parse_capabilities - parse capablity structure
* @ebus: the pointer to extended bus object
*
* Returns 0 if successful, or a negative error code.
*/
int snd_hdac_ext_bus_parse_capabilities(struct hdac_ext_bus *ebus)
{
unsigned int cur_cap;
unsigned int offset;
struct hdac_bus *bus = &ebus->bus;
unsigned int counter = 0;
offset = snd_hdac_chip_readl(bus, LLCH);
/* Lets walk the linked capabilities list */
do {
cur_cap = _snd_hdac_chip_read(l, bus, offset);
dev_dbg(bus->dev, "Capability version: 0x%x\n",
((cur_cap & AZX_CAP_HDR_VER_MASK) >> AZX_CAP_HDR_VER_OFF));
dev_dbg(bus->dev, "HDA capability ID: 0x%x\n",
(cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF);
switch ((cur_cap & AZX_CAP_HDR_ID_MASK) >> AZX_CAP_HDR_ID_OFF) {
case AZX_ML_CAP_ID:
dev_dbg(bus->dev, "Found ML capability\n");
ebus->mlcap = bus->remap_addr + offset;
break;
case AZX_GTS_CAP_ID:
dev_dbg(bus->dev, "Found GTS capability offset=%x\n", offset);
ebus->gtscap = bus->remap_addr + offset;
break;
case AZX_PP_CAP_ID:
/* PP capability found, the Audio DSP is present */
dev_dbg(bus->dev, "Found PP capability offset=%x\n", offset);
ebus->ppcap = bus->remap_addr + offset;
break;
case AZX_SPB_CAP_ID:
/* SPIB capability found, handler function */
dev_dbg(bus->dev, "Found SPB capability\n");
ebus->spbcap = bus->remap_addr + offset;
break;
case AZX_DRSM_CAP_ID:
/* DMA resume capability found, handler function */
dev_dbg(bus->dev, "Found DRSM capability\n");
ebus->drsmcap = bus->remap_addr + offset;
break;
default:
dev_dbg(bus->dev, "Unknown capability %d\n", cur_cap);
break;
}
counter++;
if (counter > HDAC_MAX_CAPS) {
dev_err(bus->dev, "We exceeded HDAC Ext capablities!!!\n");
break;
}
/* read the offset of next capabiity */
offset = cur_cap & AZX_CAP_HDR_NXT_PTR_MASK;
} while (offset);
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_parse_capabilities);
/*
* processing pipe helpers - these helpers are useful for dealing with HDA
* new capability of processing pipelines
*/
/**
* snd_hdac_ext_bus_ppcap_enable - enable/disable processing pipe capability
* @ebus: HD-audio extended core bus
* @enable: flag to turn on/off the capability
*/
void snd_hdac_ext_bus_ppcap_enable(struct hdac_ext_bus *ebus, bool enable)
{
struct hdac_bus *bus = &ebus->bus;
if (!ebus->ppcap) {
dev_err(bus->dev, "Address of PP capability is NULL");
return;
}
if (enable)
snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0, AZX_PPCTL_GPROCEN);
else
snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, AZX_PPCTL_GPROCEN, 0);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_ppcap_enable);
/**
* snd_hdac_ext_bus_ppcap_int_enable - ppcap interrupt enable/disable
* @ebus: HD-audio extended core bus
* @enable: flag to enable/disable interrupt
*/
void snd_hdac_ext_bus_ppcap_int_enable(struct hdac_ext_bus *ebus, bool enable)
{
struct hdac_bus *bus = &ebus->bus;
if (!ebus->ppcap) {
dev_err(bus->dev, "Address of PP capability is NULL\n");
return;
}
if (enable)
snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, 0, AZX_PPCTL_PIE);
else
snd_hdac_updatel(ebus->ppcap, AZX_REG_PP_PPCTL, AZX_PPCTL_PIE, 0);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_ppcap_int_enable);
/*
* Multilink helpers - these helpers are useful for dealing with HDA
* new multilink capability
*/
/**
* snd_hdac_ext_bus_get_ml_capabilities - get multilink capability
* @ebus: HD-audio extended core bus
*
* This will parse all links and read the mlink capabilities and add them
* in hlink_list of extended hdac bus
* Note: this will be freed on bus exit by driver
*/
int snd_hdac_ext_bus_get_ml_capabilities(struct hdac_ext_bus *ebus)
{
int idx;
u32 link_count;
struct hdac_ext_link *hlink;
struct hdac_bus *bus = &ebus->bus;
link_count = readl(ebus->mlcap + AZX_REG_ML_MLCD) + 1;
dev_dbg(bus->dev, "In %s Link count: %d\n", __func__, link_count);
for (idx = 0; idx < link_count; idx++) {
hlink = kzalloc(sizeof(*hlink), GFP_KERNEL);
if (!hlink)
return -ENOMEM;
hlink->index = idx;
hlink->bus = bus;
hlink->ml_addr = ebus->mlcap + AZX_ML_BASE +
(AZX_ML_INTERVAL * idx);
hlink->lcaps = readl(hlink->ml_addr + AZX_REG_ML_LCAP);
hlink->lsdiid = readw(hlink->ml_addr + AZX_REG_ML_LSDIID);
/* since link in On, update the ref */
hlink->ref_count = 1;
list_add_tail(&hlink->list, &ebus->hlink_list);
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_ml_capabilities);
/**
* snd_hdac_link_free_all- free hdac extended link objects
*
* @ebus: HD-audio ext core bus
*/
void snd_hdac_link_free_all(struct hdac_ext_bus *ebus)
{
struct hdac_ext_link *l;
while (!list_empty(&ebus->hlink_list)) {
l = list_first_entry(&ebus->hlink_list, struct hdac_ext_link, list);
list_del(&l->list);
kfree(l);
}
}
EXPORT_SYMBOL_GPL(snd_hdac_link_free_all);
/**
* snd_hdac_ext_bus_get_link_index - get link based on codec name
* @ebus: HD-audio extended core bus
* @codec_name: codec name
*/
struct hdac_ext_link *snd_hdac_ext_bus_get_link(struct hdac_ext_bus *ebus,
const char *codec_name)
{
int i;
struct hdac_ext_link *hlink = NULL;
int bus_idx, addr;
if (sscanf(codec_name, "ehdaudio%dD%d", &bus_idx, &addr) != 2)
return NULL;
if (ebus->idx != bus_idx)
return NULL;
list_for_each_entry(hlink, &ebus->hlink_list, list) {
for (i = 0; i < HDA_MAX_CODECS; i++) {
if (hlink->lsdiid & (0x1 << addr))
return hlink;
}
}
return NULL;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_get_link);
static int check_hdac_link_power_active(struct hdac_ext_link *link, bool enable)
{
int timeout;
u32 val;
int mask = (1 << AZX_MLCTL_CPA);
udelay(3);
timeout = 150;
do {
val = readl(link->ml_addr + AZX_REG_ML_LCTL);
if (enable) {
if (((val & mask) >> AZX_MLCTL_CPA))
return 0;
} else {
if (!((val & mask) >> AZX_MLCTL_CPA))
return 0;
}
udelay(3);
} while (--timeout);
return -EIO;
}
/**
* snd_hdac_ext_bus_link_power_up -power up hda link
* @link: HD-audio extended link
*/
int snd_hdac_ext_bus_link_power_up(struct hdac_ext_link *link)
{
snd_hdac_updatel(link->ml_addr, AZX_REG_ML_LCTL, 0, AZX_MLCTL_SPA);
return check_hdac_link_power_active(link, true);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_up);
/**
* snd_hdac_ext_bus_link_power_down -power down hda link
* @link: HD-audio extended link
*/
int snd_hdac_ext_bus_link_power_down(struct hdac_ext_link *link)
{
snd_hdac_updatel(link->ml_addr, AZX_REG_ML_LCTL, AZX_MLCTL_SPA, 0);
return check_hdac_link_power_active(link, false);
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_down);
/**
* snd_hdac_ext_bus_link_power_up_all -power up all hda link
* @ebus: HD-audio extended bus
*/
int snd_hdac_ext_bus_link_power_up_all(struct hdac_ext_bus *ebus)
{
struct hdac_ext_link *hlink = NULL;
int ret;
list_for_each_entry(hlink, &ebus->hlink_list, list) {
snd_hdac_updatel(hlink->ml_addr,
AZX_REG_ML_LCTL, 0, AZX_MLCTL_SPA);
ret = check_hdac_link_power_active(hlink, true);
if (ret < 0)
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_up_all);
/**
* snd_hdac_ext_bus_link_power_down_all -power down all hda link
* @ebus: HD-audio extended bus
*/
int snd_hdac_ext_bus_link_power_down_all(struct hdac_ext_bus *ebus)
{
struct hdac_ext_link *hlink = NULL;
int ret;
list_for_each_entry(hlink, &ebus->hlink_list, list) {
snd_hdac_updatel(hlink->ml_addr, AZX_REG_ML_LCTL, AZX_MLCTL_SPA, 0);
ret = check_hdac_link_power_active(hlink, false);
if (ret < 0)
return ret;
}
return 0;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_power_down_all);
int snd_hdac_ext_bus_link_get(struct hdac_ext_bus *ebus,
struct hdac_ext_link *link)
{
int ret = 0;
mutex_lock(&ebus->lock);
/*
* if we move from 0 to 1, count will be 1 so power up this link
* as well, also check the dma status and trigger that
*/
if (++link->ref_count == 1) {
if (!ebus->cmd_dma_state) {
snd_hdac_bus_init_cmd_io(&ebus->bus);
ebus->cmd_dma_state = true;
}
ret = snd_hdac_ext_bus_link_power_up(link);
}
mutex_unlock(&ebus->lock);
return ret;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_get);
int snd_hdac_ext_bus_link_put(struct hdac_ext_bus *ebus,
struct hdac_ext_link *link)
{
int ret = 0;
struct hdac_ext_link *hlink;
bool link_up = false;
mutex_lock(&ebus->lock);
/*
* if we move from 1 to 0, count will be 0
* so power down this link as well
*/
if (--link->ref_count == 0) {
ret = snd_hdac_ext_bus_link_power_down(link);
/*
* now check if all links are off, if so turn off
* cmd dma as well
*/
list_for_each_entry(hlink, &ebus->hlink_list, list) {
if (hlink->ref_count) {
link_up = true;
break;
}
}
if (!link_up) {
snd_hdac_bus_stop_cmd_io(&ebus->bus);
ebus->cmd_dma_state = false;
}
}
mutex_unlock(&ebus->lock);
return ret;
}
EXPORT_SYMBOL_GPL(snd_hdac_ext_bus_link_put);