linux-stable/sound/pci/cs5535audio/cs5535audio_pcm.c
Andres Salomon 222fa0b0d2 [ALSA] cs5535audio: fix PRD register save/restore power management race
In the suspend path, we currently save the PRD registers and then disable DMA.
This is racy; the sound hardware might update the PRD register as it finishes
processing some DMA pages between when we've saved the PRD registers and
when DMA actually gets disabled.  Furthermore, we actively check whether or
not DMA is enabled before saving PRD registers; there's no reason to do that,
as the PRD registers should not update when we twiddle the ACC_BM[x]_CMD
register(s).  Worst case, we save the PRD registers twice; even powering
down the ACC shouldn't mess with the PRD registers (according to the 5536
data sheet, section 5.3.7.4, power-down procedure).  This patch reworks
all that to first disable DMA, and then save PRD registers.

Signed-off-by: Andres Salomon <dilinger@debian.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>
2007-10-16 15:59:52 +02:00

437 lines
12 KiB
C

/*
* Driver for audio on multifunction CS5535 companion device
* Copyright (C) Jaya Kumar
*
* Based on Jaroslav Kysela and Takashi Iwai's examples.
* This work was sponsored by CIS(M) Sdn Bhd.
*
* 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; either version 2 of the License, or
* (at your option) any later version.
*
* 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* todo: add be fmt support, spdif, pm
*/
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/pci.h>
#include <sound/driver.h>
#include <sound/core.h>
#include <sound/control.h>
#include <sound/initval.h>
#include <sound/asoundef.h>
#include <sound/pcm.h>
#include <sound/pcm_params.h>
#include <sound/ac97_codec.h>
#include "cs5535audio.h"
static struct snd_pcm_hardware snd_cs5535audio_playback =
{
.info = (
SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP_VALID |
SNDRV_PCM_INFO_PAUSE |
SNDRV_PCM_INFO_RESUME
),
.formats = (
SNDRV_PCM_FMTBIT_S16_LE
),
.rates = (
SNDRV_PCM_RATE_CONTINUOUS |
SNDRV_PCM_RATE_8000_48000
),
.rate_min = 4000,
.rate_max = 48000,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = (128*1024),
.period_bytes_min = 64,
.period_bytes_max = (64*1024 - 16),
.periods_min = 1,
.periods_max = CS5535AUDIO_MAX_DESCRIPTORS,
.fifo_size = 0,
};
static struct snd_pcm_hardware snd_cs5535audio_capture =
{
.info = (
SNDRV_PCM_INFO_MMAP |
SNDRV_PCM_INFO_INTERLEAVED |
SNDRV_PCM_INFO_BLOCK_TRANSFER |
SNDRV_PCM_INFO_MMAP_VALID
),
.formats = (
SNDRV_PCM_FMTBIT_S16_LE
),
.rates = (
SNDRV_PCM_RATE_CONTINUOUS |
SNDRV_PCM_RATE_8000_48000
),
.rate_min = 4000,
.rate_max = 48000,
.channels_min = 2,
.channels_max = 2,
.buffer_bytes_max = (128*1024),
.period_bytes_min = 64,
.period_bytes_max = (64*1024 - 16),
.periods_min = 1,
.periods_max = CS5535AUDIO_MAX_DESCRIPTORS,
.fifo_size = 0,
};
static int snd_cs5535audio_playback_open(struct snd_pcm_substream *substream)
{
int err;
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
struct snd_pcm_runtime *runtime = substream->runtime;
runtime->hw = snd_cs5535audio_playback;
cs5535au->playback_substream = substream;
runtime->private_data = &(cs5535au->dmas[CS5535AUDIO_DMA_PLAYBACK]);
if ((err = snd_pcm_hw_constraint_integer(runtime,
SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
return err;
return 0;
}
static int snd_cs5535audio_playback_close(struct snd_pcm_substream *substream)
{
return 0;
}
#define CS5535AUDIO_DESC_LIST_SIZE \
PAGE_ALIGN(CS5535AUDIO_MAX_DESCRIPTORS * sizeof(struct cs5535audio_dma_desc))
static int cs5535audio_build_dma_packets(struct cs5535audio *cs5535au,
struct cs5535audio_dma *dma,
struct snd_pcm_substream *substream,
unsigned int periods,
unsigned int period_bytes)
{
unsigned int i;
u32 addr, desc_addr, jmpprd_addr;
struct cs5535audio_dma_desc *lastdesc;
if (periods > CS5535AUDIO_MAX_DESCRIPTORS)
return -ENOMEM;
if (dma->desc_buf.area == NULL) {
if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
snd_dma_pci_data(cs5535au->pci),
CS5535AUDIO_DESC_LIST_SIZE+1,
&dma->desc_buf) < 0)
return -ENOMEM;
dma->period_bytes = dma->periods = 0;
}
if (dma->periods == periods && dma->period_bytes == period_bytes)
return 0;
/* the u32 cast is okay because in snd*create we successfully told
pci alloc that we're only 32 bit capable so the uppper will be 0 */
addr = (u32) substream->runtime->dma_addr;
desc_addr = (u32) dma->desc_buf.addr;
for (i = 0; i < periods; i++) {
struct cs5535audio_dma_desc *desc =
&((struct cs5535audio_dma_desc *) dma->desc_buf.area)[i];
desc->addr = cpu_to_le32(addr);
desc->size = cpu_to_le32(period_bytes);
desc->ctlreserved = cpu_to_le32(PRD_EOP);
desc_addr += sizeof(struct cs5535audio_dma_desc);
addr += period_bytes;
}
/* we reserved one dummy descriptor at the end to do the PRD jump */
lastdesc = &((struct cs5535audio_dma_desc *) dma->desc_buf.area)[periods];
lastdesc->addr = cpu_to_le32((u32) dma->desc_buf.addr);
lastdesc->size = 0;
lastdesc->ctlreserved = cpu_to_le32(PRD_JMP);
jmpprd_addr = cpu_to_le32(lastdesc->addr +
(sizeof(struct cs5535audio_dma_desc)*periods));
dma->substream = substream;
dma->period_bytes = period_bytes;
dma->periods = periods;
spin_lock_irq(&cs5535au->reg_lock);
dma->ops->disable_dma(cs5535au);
dma->ops->setup_prd(cs5535au, jmpprd_addr);
spin_unlock_irq(&cs5535au->reg_lock);
return 0;
}
static void cs5535audio_playback_enable_dma(struct cs5535audio *cs5535au)
{
cs_writeb(cs5535au, ACC_BM0_CMD, BM_CTL_EN);
}
static void cs5535audio_playback_disable_dma(struct cs5535audio *cs5535au)
{
cs_writeb(cs5535au, ACC_BM0_CMD, 0);
}
static void cs5535audio_playback_pause_dma(struct cs5535audio *cs5535au)
{
cs_writeb(cs5535au, ACC_BM0_CMD, BM_CTL_PAUSE);
}
static void cs5535audio_playback_setup_prd(struct cs5535audio *cs5535au,
u32 prd_addr)
{
cs_writel(cs5535au, ACC_BM0_PRD, prd_addr);
}
static u32 cs5535audio_playback_read_prd(struct cs5535audio *cs5535au)
{
return cs_readl(cs5535au, ACC_BM0_PRD);
}
static u32 cs5535audio_playback_read_dma_pntr(struct cs5535audio *cs5535au)
{
return cs_readl(cs5535au, ACC_BM0_PNTR);
}
static void cs5535audio_capture_enable_dma(struct cs5535audio *cs5535au)
{
cs_writeb(cs5535au, ACC_BM1_CMD, BM_CTL_EN);
}
static void cs5535audio_capture_disable_dma(struct cs5535audio *cs5535au)
{
cs_writeb(cs5535au, ACC_BM1_CMD, 0);
}
static void cs5535audio_capture_pause_dma(struct cs5535audio *cs5535au)
{
cs_writeb(cs5535au, ACC_BM1_CMD, BM_CTL_PAUSE);
}
static void cs5535audio_capture_setup_prd(struct cs5535audio *cs5535au,
u32 prd_addr)
{
cs_writel(cs5535au, ACC_BM1_PRD, prd_addr);
}
static u32 cs5535audio_capture_read_prd(struct cs5535audio *cs5535au)
{
return cs_readl(cs5535au, ACC_BM1_PRD);
}
static u32 cs5535audio_capture_read_dma_pntr(struct cs5535audio *cs5535au)
{
return cs_readl(cs5535au, ACC_BM1_PNTR);
}
static void cs5535audio_clear_dma_packets(struct cs5535audio *cs5535au,
struct cs5535audio_dma *dma,
struct snd_pcm_substream *substream)
{
snd_dma_free_pages(&dma->desc_buf);
dma->desc_buf.area = NULL;
dma->substream = NULL;
}
static int snd_cs5535audio_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *hw_params)
{
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
struct cs5535audio_dma *dma = substream->runtime->private_data;
int err;
err = snd_pcm_lib_malloc_pages(substream,
params_buffer_bytes(hw_params));
if (err < 0)
return err;
dma->buf_addr = substream->runtime->dma_addr;
dma->buf_bytes = params_buffer_bytes(hw_params);
err = cs5535audio_build_dma_packets(cs5535au, dma, substream,
params_periods(hw_params),
params_period_bytes(hw_params));
return err;
}
static int snd_cs5535audio_hw_free(struct snd_pcm_substream *substream)
{
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
struct cs5535audio_dma *dma = substream->runtime->private_data;
cs5535audio_clear_dma_packets(cs5535au, dma, substream);
return snd_pcm_lib_free_pages(substream);
}
static int snd_cs5535audio_playback_prepare(struct snd_pcm_substream *substream)
{
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
return snd_ac97_set_rate(cs5535au->ac97, AC97_PCM_FRONT_DAC_RATE,
substream->runtime->rate);
}
static int snd_cs5535audio_trigger(struct snd_pcm_substream *substream, int cmd)
{
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
struct cs5535audio_dma *dma = substream->runtime->private_data;
int err = 0;
spin_lock(&cs5535au->reg_lock);
switch (cmd) {
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
dma->ops->pause_dma(cs5535au);
break;
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
dma->ops->enable_dma(cs5535au);
break;
case SNDRV_PCM_TRIGGER_START:
dma->ops->enable_dma(cs5535au);
break;
case SNDRV_PCM_TRIGGER_RESUME:
dma->ops->enable_dma(cs5535au);
break;
case SNDRV_PCM_TRIGGER_STOP:
dma->ops->disable_dma(cs5535au);
break;
case SNDRV_PCM_TRIGGER_SUSPEND:
dma->ops->disable_dma(cs5535au);
break;
default:
snd_printk(KERN_ERR "unhandled trigger\n");
err = -EINVAL;
break;
}
spin_unlock(&cs5535au->reg_lock);
return err;
}
static snd_pcm_uframes_t snd_cs5535audio_pcm_pointer(struct snd_pcm_substream
*substream)
{
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
u32 curdma;
struct cs5535audio_dma *dma;
dma = substream->runtime->private_data;
curdma = dma->ops->read_dma_pntr(cs5535au);
if (curdma < dma->buf_addr) {
snd_printk(KERN_ERR "curdma=%x < %x bufaddr.\n",
curdma, dma->buf_addr);
return 0;
}
curdma -= dma->buf_addr;
if (curdma >= dma->buf_bytes) {
snd_printk(KERN_ERR "diff=%x >= %x buf_bytes.\n",
curdma, dma->buf_bytes);
return 0;
}
return bytes_to_frames(substream->runtime, curdma);
}
static int snd_cs5535audio_capture_open(struct snd_pcm_substream *substream)
{
int err;
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
struct snd_pcm_runtime *runtime = substream->runtime;
runtime->hw = snd_cs5535audio_capture;
cs5535au->capture_substream = substream;
runtime->private_data = &(cs5535au->dmas[CS5535AUDIO_DMA_CAPTURE]);
if ((err = snd_pcm_hw_constraint_integer(runtime,
SNDRV_PCM_HW_PARAM_PERIODS)) < 0)
return err;
return 0;
}
static int snd_cs5535audio_capture_close(struct snd_pcm_substream *substream)
{
return 0;
}
static int snd_cs5535audio_capture_prepare(struct snd_pcm_substream *substream)
{
struct cs5535audio *cs5535au = snd_pcm_substream_chip(substream);
return snd_ac97_set_rate(cs5535au->ac97, AC97_PCM_LR_ADC_RATE,
substream->runtime->rate);
}
static struct snd_pcm_ops snd_cs5535audio_playback_ops = {
.open = snd_cs5535audio_playback_open,
.close = snd_cs5535audio_playback_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = snd_cs5535audio_hw_params,
.hw_free = snd_cs5535audio_hw_free,
.prepare = snd_cs5535audio_playback_prepare,
.trigger = snd_cs5535audio_trigger,
.pointer = snd_cs5535audio_pcm_pointer,
};
static struct snd_pcm_ops snd_cs5535audio_capture_ops = {
.open = snd_cs5535audio_capture_open,
.close = snd_cs5535audio_capture_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = snd_cs5535audio_hw_params,
.hw_free = snd_cs5535audio_hw_free,
.prepare = snd_cs5535audio_capture_prepare,
.trigger = snd_cs5535audio_trigger,
.pointer = snd_cs5535audio_pcm_pointer,
};
static struct cs5535audio_dma_ops snd_cs5535audio_playback_dma_ops = {
.type = CS5535AUDIO_DMA_PLAYBACK,
.enable_dma = cs5535audio_playback_enable_dma,
.disable_dma = cs5535audio_playback_disable_dma,
.setup_prd = cs5535audio_playback_setup_prd,
.read_prd = cs5535audio_playback_read_prd,
.pause_dma = cs5535audio_playback_pause_dma,
.read_dma_pntr = cs5535audio_playback_read_dma_pntr,
};
static struct cs5535audio_dma_ops snd_cs5535audio_capture_dma_ops = {
.type = CS5535AUDIO_DMA_CAPTURE,
.enable_dma = cs5535audio_capture_enable_dma,
.disable_dma = cs5535audio_capture_disable_dma,
.setup_prd = cs5535audio_capture_setup_prd,
.read_prd = cs5535audio_capture_read_prd,
.pause_dma = cs5535audio_capture_pause_dma,
.read_dma_pntr = cs5535audio_capture_read_dma_pntr,
};
int __devinit snd_cs5535audio_pcm(struct cs5535audio *cs5535au)
{
struct snd_pcm *pcm;
int err;
err = snd_pcm_new(cs5535au->card, "CS5535 Audio", 0, 1, 1, &pcm);
if (err < 0)
return err;
cs5535au->dmas[CS5535AUDIO_DMA_PLAYBACK].ops =
&snd_cs5535audio_playback_dma_ops;
cs5535au->dmas[CS5535AUDIO_DMA_CAPTURE].ops =
&snd_cs5535audio_capture_dma_ops;
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_PLAYBACK,
&snd_cs5535audio_playback_ops);
snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE,
&snd_cs5535audio_capture_ops);
pcm->private_data = cs5535au;
pcm->info_flags = 0;
strcpy(pcm->name, "CS5535 Audio");
snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV,
snd_dma_pci_data(cs5535au->pci),
64*1024, 128*1024);
cs5535au->pcm = pcm;
return 0;
}