hac.c
// SPDX-License-Identifier: GPL-2.0
//
// Hitachi Audio Controller (AC97) support for SH7760/SH7780
//
// Copyright (c) 2007 Manuel Lauss <mano@roarinelk.homelinux.net>
//
// dont forget to set IPSEL/OMSEL register bits (in your board code) to
// enable HAC output pins!
/* BIG FAT FIXME: although the SH7760 has 2 independent AC97 units, only
* the FIRST can be used since ASoC does not pass any information to the
* ac97_read/write() functions regarding WHICH unit to use. You'll have
* to edit the code a bit to use the other AC97 unit. --mlau
*/
#include <linux/init.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/wait.h>
#include <linux/delay.h>
#include <sound/core.h>
#include <sound/pcm.h>
#include <sound/ac97_codec.h>
#include <sound/initval.h>
#include <sound/soc.h>
/* regs and bits */
#define HACCR 0x08
#define HACCSAR 0x20
#define HACCSDR 0x24
#define HACPCML 0x28
#define HACPCMR 0x2C
#define HACTIER 0x50
#define HACTSR 0x54
#define HACRIER 0x58
#define HACRSR 0x5C
#define HACACR 0x60
#define CR_CR (1 << 15) /* "codec-ready" indicator */
#define CR_CDRT (1 << 11) /* cold reset */
#define CR_WMRT (1 << 10) /* warm reset */
#define CR_B9 (1 << 9) /* the mysterious "bit 9" */
#define CR_ST (1 << 5) /* AC97 link start bit */
#define CSAR_RD (1 << 19) /* AC97 data read bit */
#define CSAR_WR (0)
#define TSR_CMDAMT (1 << 31)
#define TSR_CMDDMT (1 << 30)
#define RSR_STARY (1 << 22)
#define RSR_STDRY (1 << 21)
#define ACR_DMARX16 (1 << 30)
#define ACR_DMATX16 (1 << 29)
#define ACR_TX12ATOM (1 << 26)
#define ACR_DMARX20 ((1 << 24) | (1 << 22))
#define ACR_DMATX20 ((1 << 23) | (1 << 21))
#define CSDR_SHIFT 4
#define CSDR_MASK (0xffff << CSDR_SHIFT)
#define CSAR_SHIFT 12
#define CSAR_MASK (0x7f << CSAR_SHIFT)
#define AC97_WRITE_RETRY 1
#define AC97_READ_RETRY 5
/* manual-suggested AC97 codec access timeouts (us) */
#define TMO_E1 500 /* 21 < E1 < 1000 */
#define TMO_E2 13 /* 13 < E2 */
#define TMO_E3 21 /* 21 < E3 */
#define TMO_E4 500 /* 21 < E4 < 1000 */
struct hac_priv {
unsigned long mmio; /* HAC base address */
} hac_cpu_data[] = {
#if defined(CONFIG_CPU_SUBTYPE_SH7760)
{
.mmio = 0xFE240000,
},
{
.mmio = 0xFE250000,
},
#elif defined(CONFIG_CPU_SUBTYPE_SH7780)
{
.mmio = 0xFFE40000,
},
#else
#error "Unsupported SuperH SoC"
#endif
};
#define HACREG(reg) (*(unsigned long *)(hac->mmio + (reg)))
/*
* AC97 read/write flow as outlined in the SH7760 manual (pages 903-906)
*/
static int hac_get_codec_data(struct hac_priv *hac, unsigned short r,
unsigned short *v)
{
unsigned int to1, to2, i;
unsigned short adr;
for (i = AC97_READ_RETRY; i; i--) {
*v = 0;
/* wait for HAC to receive something from the codec */
for (to1 = TMO_E4;
to1 && !(HACREG(HACRSR) & RSR_STARY);
--to1)
udelay(1);
for (to2 = TMO_E4;
to2 && !(HACREG(HACRSR) & RSR_STDRY);
--to2)
udelay(1);
if (!to1 && !to2)
return 0; /* codec comm is down */
adr = ((HACREG(HACCSAR) & CSAR_MASK) >> CSAR_SHIFT);
*v = ((HACREG(HACCSDR) & CSDR_MASK) >> CSDR_SHIFT);
HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
if (r == adr)
break;
/* manual says: wait at least 21 usec before retrying */
udelay(21);
}
HACREG(HACRSR) &= ~(RSR_STDRY | RSR_STARY);
return i;
}
static unsigned short hac_read_codec_aux(struct hac_priv *hac,
unsigned short reg)
{
unsigned short val;
unsigned int i, to;
for (i = AC97_READ_RETRY; i; i--) {
/* send_read_request */
local_irq_disable();
HACREG(HACTSR) &= ~(TSR_CMDAMT);
HACREG(HACCSAR) = (reg << CSAR_SHIFT) | CSAR_RD;
local_irq_enable();
for (to = TMO_E3;
to && !(HACREG(HACTSR) & TSR_CMDAMT);
--to)
udelay(1);
HACREG(HACTSR) &= ~TSR_CMDAMT;
val = 0;
if (hac_get_codec_data(hac, reg, &val) != 0)
break;
}
return i ? val : ~0;
}
static void hac_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
unsigned short val)
{
int unit_id = 0 /* ac97->private_data */;
struct hac_priv *hac = &hac_cpu_data[unit_id];
unsigned int i, to;
/* write_codec_aux */
for (i = AC97_WRITE_RETRY; i; i--) {
/* send_write_request */
local_irq_disable();
HACREG(HACTSR) &= ~(TSR_CMDDMT | TSR_CMDAMT);
HACREG(HACCSDR) = (val << CSDR_SHIFT);
HACREG(HACCSAR) = (reg << CSAR_SHIFT) & (~CSAR_RD);
local_irq_enable();
/* poll-wait for CMDAMT and CMDDMT */
for (to = TMO_E1;
to && !(HACREG(HACTSR) & (TSR_CMDAMT|TSR_CMDDMT));
--to)
udelay(1);
HACREG(HACTSR) &= ~(TSR_CMDAMT | TSR_CMDDMT);
if (to)
break;
/* timeout, try again */
}
}
static unsigned short hac_ac97_read(struct snd_ac97 *ac97,
unsigned short reg)
{
int unit_id = 0 /* ac97->private_data */;
struct hac_priv *hac = &hac_cpu_data[unit_id];
return hac_read_codec_aux(hac, reg);
}
static void hac_ac97_warmrst(struct snd_ac97 *ac97)
{
int unit_id = 0 /* ac97->private_data */;
struct hac_priv *hac = &hac_cpu_data[unit_id];
unsigned int tmo;
HACREG(HACCR) = CR_WMRT | CR_ST | CR_B9;
msleep(10);
HACREG(HACCR) = CR_ST | CR_B9;
for (tmo = 1000; (tmo > 0) && !(HACREG(HACCR) & CR_CR); tmo--)
udelay(1);
if (!tmo)
printk(KERN_INFO "hac: reset: AC97 link down!\n");
/* settings this bit lets us have a conversation with codec */
HACREG(HACACR) |= ACR_TX12ATOM;
}
static void hac_ac97_coldrst(struct snd_ac97 *ac97)
{
int unit_id = 0 /* ac97->private_data */;
struct hac_priv *hac;
hac = &hac_cpu_data[unit_id];
HACREG(HACCR) = 0;
HACREG(HACCR) = CR_CDRT | CR_ST | CR_B9;
msleep(10);
hac_ac97_warmrst(ac97);
}
static struct snd_ac97_bus_ops hac_ac97_ops = {
.read = hac_ac97_read,
.write = hac_ac97_write,
.reset = hac_ac97_coldrst,
.warm_reset = hac_ac97_warmrst,
};
static int hac_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params,
struct snd_soc_dai *dai)
{
struct hac_priv *hac = &hac_cpu_data[dai->id];
int d = substream->stream == SNDRV_PCM_STREAM_PLAYBACK ? 0 : 1;
switch (params->msbits) {
case 16:
HACREG(HACACR) |= d ? ACR_DMARX16 : ACR_DMATX16;
HACREG(HACACR) &= d ? ~ACR_DMARX20 : ~ACR_DMATX20;
break;
case 20:
HACREG(HACACR) &= d ? ~ACR_DMARX16 : ~ACR_DMATX16;
HACREG(HACACR) |= d ? ACR_DMARX20 : ACR_DMATX20;
break;
default:
pr_debug("hac: invalid depth %d bit\n", params->msbits);
return -EINVAL;
break;
}
return 0;
}
#define AC97_RATES \
SNDRV_PCM_RATE_8000_192000
#define AC97_FMTS \
SNDRV_PCM_FMTBIT_S16_LE
static const struct snd_soc_dai_ops hac_dai_ops = {
.hw_params = hac_hw_params,
};
static struct snd_soc_dai_driver sh4_hac_dai[] = {
{
.name = "hac-dai.0",
.bus_control = true,
.playback = {
.rates = AC97_RATES,
.formats = AC97_FMTS,
.channels_min = 2,
.channels_max = 2,
},
.capture = {
.rates = AC97_RATES,
.formats = AC97_FMTS,
.channels_min = 2,
.channels_max = 2,
},
.ops = &hac_dai_ops,
},
#ifdef CONFIG_CPU_SUBTYPE_SH7760
{
.name = "hac-dai.1",
.id = 1,
.playback = {
.rates = AC97_RATES,
.formats = AC97_FMTS,
.channels_min = 2,
.channels_max = 2,
},
.capture = {
.rates = AC97_RATES,
.formats = AC97_FMTS,
.channels_min = 2,
.channels_max = 2,
},
.ops = &hac_dai_ops,
},
#endif
};
static const struct snd_soc_component_driver sh4_hac_component = {
.name = "sh4-hac",
};
static int hac_soc_platform_probe(struct platform_device *pdev)
{
int ret;
ret = snd_soc_set_ac97_ops(&hac_ac97_ops);
if (ret != 0)
return ret;
return devm_snd_soc_register_component(&pdev->dev, &sh4_hac_component,
sh4_hac_dai, ARRAY_SIZE(sh4_hac_dai));
}
static int hac_soc_platform_remove(struct platform_device *pdev)
{
snd_soc_set_ac97_ops(NULL);
return 0;
}
static struct platform_driver hac_pcm_driver = {
.driver = {
.name = "hac-pcm-audio",
},
.probe = hac_soc_platform_probe,
.remove = hac_soc_platform_remove,
};
module_platform_driver(hac_pcm_driver);
MODULE_LICENSE("GPL v2");
MODULE_DESCRIPTION("SuperH onchip HAC (AC97) audio driver");
MODULE_AUTHOR("Manuel Lauss <mano@roarinelk.homelinux.net>");