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本章讨论一下 smdk4412的 I2S 接口
1. I2S的硬件连接
在tiny4412 上搭载的codec 是wm8960 ,如下图
在上图中，可以清楚的知道 I2S的 Xi2CDCLKO 、Xi2aSCLK0、Xi2sLRCLK0、Xi2sSDO0_0、Xi2sSDI0 连接到了codec 对应的引脚上。
这些label 对应的pin 脚是那些呢？ 如下图所示，分别连接到了 GPZ0-6 , 总共7个pin 脚上。
I2S 连接的pin 脚都是存在复用功能。 查看4412 的spec 可以知道设置对应的bit 为0x2 才设置成I2S 的接口。
DMA 选择哪一个DMA , 选择哪个一个channel
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2.code
i2s
/* sound/soc/samsung/i2s.c
*
* ALSA SoC Audio Layer - Samsung I2S Controller driver
*
* Copyright (c) 2010 Samsung Electronics Co. Ltd.
* Jaswinder Singh <[email protected]>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <sound/soc.h>
#include <sound/pcm_params.h>
#include <plat/audio.h>
#include <mach/map.h>
#include <mach/regs-clock.h>
#include <mach/regs-audss.h>
#include "audss.h"
#include "dma.h"
#include "idma.h"
#include "i2s.h"
#include "srp-types.h"
#if defined(CONFIG_SND_SAMSUNG_RP) && \
(defined(CONFIG_MACH_U1) || defined(CONFIG_MACH_TRATS))
#define USE_ALT_REG_RECOVER
#endif
struct i2s_dai {
/* Platform device for this DAI */
struct platform_device *pdev;
/* IOREMAP'd SFRs */
void __iomem *addr;
/* Physical base address of SFRs */
u32 base;
/* CMU's clock for I2S 1,2 interfaces */
struct clk *cclk;
/* Rate of RCLK source clock */
unsigned long rclk_srcrate;
/* Frame Clock */
unsigned frmclk;
/*
* Specifically requested RCLK,BCLK by MACHINE Driver.
* 0 indicates CPU driver is free to choose any value.
*/
unsigned rfs, bfs;
/* Clock for generating I2S signals */
struct clk *op_clk;
/* Array of clock names for op_clk */
const char **src_clk;
/* Pointer to the Primary_Fifo if this is Sec_Fifo, NULL otherwise */
struct i2s_dai *pri_dai;
/* Pointer to the Secondary_Fifo if it has one, NULL otherwise */
struct i2s_dai *sec_dai;
#define DAI_OPENED (1 << 0) /* Dai is opened */
#define DAI_MANAGER (1 << 1) /* Dai is the manager */
unsigned mode;
/* Driver for this DAI */
struct snd_soc_dai_driver i2s_dai_drv;
/* DMA parameters */
struct s3c_dma_params dma_playback;
struct s3c_dma_params dma_capture;
u32 quirks;
u32 suspend_i2smod;
u32 suspend_i2scon;
u32 suspend_i2spsr;
u32 suspend_i2sahb[((I2SSTR1 - I2SAHB) >> 2) + 1];
bool tx_active;
bool rx_active;
bool reg_saved;
bool reg_saved_by_pm;
void (*audss_clk_enable)(bool enable);
void (*audss_suspend)(void);
void (*audss_resume)(void);
};
/* Lock for cross i/f checks */
static DEFINE_SPINLOCK(lock);
/* If SRP is enabled for ULP audio */
static inline bool is_srp_enabled(struct i2s_dai *i2s, u32 stream)
{
if ((stream == SNDRV_PCM_STREAM_PLAYBACK)
&& (i2s->quirks & QUIRK_ENABLED_SRP))
return true;
else
return false;
}
/* Get srp status(opened/running) information */
static inline int srp_active(struct i2s_dai *i2s, int cmd)
{
#if defined(CONFIG_SND_SAMSUNG_RP) || defined(CONFIG_SND_SAMSUNG_ALP)
if ((i2s->pdev->id == 0) || (i2s->pdev->id == SAMSUNG_I2S_SECOFF))
return srp_get_status(cmd);
else
return 0;
#else
return 0;
#endif
}
/* If this is the 'overlay' stereo DAI */
static inline bool is_secondary(struct i2s_dai *i2s)
{
return i2s->pri_dai ? true : false;
}
/* If operating in SoC-Slave mode */
static inline bool is_slave(struct i2s_dai *i2s)
{
return (readl(i2s->addr + I2SMOD) & MOD_SLAVE) ? true : false;
}
/* If this interface of the controller is transmitting data */
static inline bool tx_active(struct i2s_dai *i2s)
{
u32 active;
if (!i2s || !i2s->addr)
return false;
active = readl(i2s->addr + I2SCON);
if (is_secondary(i2s))
active &= CON_TXSDMA_ACTIVE;
else
active &= CON_TXDMA_ACTIVE;
return active ? true : false;
}
/* If the other interface of the controller is transmitting data */
static inline bool other_tx_active(struct i2s_dai *i2s)
{
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
return tx_active(other);
}
/* If any interface of the controller is transmitting data */
static inline bool any_tx_active(struct i2s_dai *i2s)
{
return tx_active(i2s) || other_tx_active(i2s);
}
/* If this interface of the controller is receiving data */
static inline bool rx_active(struct i2s_dai *i2s)
{
u32 active;
if (!i2s || !i2s->addr)
return false;
active = readl(i2s->addr + I2SCON) & CON_RXDMA_ACTIVE;
return active ? true : false;
}
/* If the other interface of the controller is receiving data */
static inline bool other_rx_active(struct i2s_dai *i2s)
{
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
return rx_active(other);
}
/* If any interface of the controller is receiving data */
static inline bool any_rx_active(struct i2s_dai *i2s)
{
return rx_active(i2s) || other_rx_active(i2s);
}
/* If the other DAI is transmitting or receiving data */
static inline bool other_active(struct i2s_dai *i2s)
{
return other_rx_active(i2s) || other_tx_active(i2s);
}
/* If this DAI is transmitting or receiving data */
static inline bool this_active(struct i2s_dai *i2s)
{
return tx_active(i2s) || rx_active(i2s);
}
/* If the controller is active anyway */
static inline bool any_active(struct i2s_dai *i2s)
{
return this_active(i2s) || other_active(i2s);
}
static inline struct i2s_dai *to_info(struct snd_soc_dai *dai)
{
return snd_soc_dai_get_drvdata(dai);
}
static inline bool is_opened(struct i2s_dai *i2s)
{
if (i2s && (i2s->mode & DAI_OPENED))
return true;
else
return false;
}
static inline bool is_manager(struct i2s_dai *i2s)
{
if (is_opened(i2s) && (i2s->mode & DAI_MANAGER))
return true;
else
return false;
}
/* Read RCLK of I2S (in multiples of LRCLK) */
static inline unsigned get_rfs(struct i2s_dai *i2s)
{
u32 rfs = (readl(i2s->addr + I2SMOD) >> 3) & 0x3;
switch (rfs) {
case 3: return 768;
case 2: return 384;
case 1: return 512;
default: return 256;
}
}
/* Write RCLK of I2S (in multiples of LRCLK) */
static inline void set_rfs(struct i2s_dai *i2s, unsigned rfs)
{
u32 mod = readl(i2s->addr + I2SMOD);
mod &= ~MOD_RCLK_MASK;
switch (rfs) {
case 768:
mod |= MOD_RCLK_768FS;
break;
case 512:
mod |= MOD_RCLK_512FS;
break;
case 384:
mod |= MOD_RCLK_384FS;
break;
default:
mod |= MOD_RCLK_256FS;
break;
}
writel(mod, i2s->addr + I2SMOD);
}
/* Read Bit-Clock of I2S (in multiples of LRCLK) */
static inline unsigned get_bfs(struct i2s_dai *i2s)
{
u32 bfs = (readl(i2s->addr + I2SMOD) >> 1) & 0x3;
switch (bfs) {
case 3: return 24;
case 2: return 16;
case 1: return 48;
default: return 32;
}
}
/* Write Bit-Clock of I2S (in multiples of LRCLK) */
static inline void set_bfs(struct i2s_dai *i2s, unsigned bfs)
{
u32 mod = readl(i2s->addr + I2SMOD);
mod &= ~MOD_BCLK_MASK;
switch (bfs) {
case 48:
mod |= MOD_BCLK_48FS;
break;
case 32:
mod |= MOD_BCLK_32FS;
break;
case 24:
mod |= MOD_BCLK_24FS;
break;
case 16:
mod |= MOD_BCLK_16FS;
break;
default:
dev_err(&i2s->pdev->dev, "Wrong BCLK Divider!\n");
return;
}
writel(mod, i2s->addr + I2SMOD);
}
/* Sample-Size */
static inline int get_blc(struct i2s_dai *i2s)
{
int blc = readl(i2s->addr + I2SMOD);
blc = (blc >> 13) & 0x3;
switch (blc) {
case 2: return 24;
case 1: return 8;
default: return 16;
}
}
/* TX Channel Control */
static void i2s_txctrl(struct i2s_dai *i2s, int on, int stream)
{
void __iomem *addr = i2s->addr;
u32 con = readl(addr + I2SCON);
u32 mod = readl(addr + I2SMOD) & ~MOD_MASK;
if (on) {
printk(KERN_DEBUG "%s:Turn on\n", __func__);
con |= CON_ACTIVE;
con &= ~CON_TXCH_PAUSE;
if (is_secondary(i2s)) {
con |= CON_TXSDMA_ACTIVE;
con &= ~CON_TXSDMA_PAUSE;
} else {
con |= CON_TXDMA_ACTIVE;
con &= ~CON_TXDMA_PAUSE;
}
if (any_rx_active(i2s))
mod |= MOD_TXRX;
else
mod |= MOD_TXONLY;
} else {
if (is_secondary(i2s)) {
con |= CON_TXSDMA_PAUSE;
con &= ~CON_TXSDMA_ACTIVE;
} else {
con |= CON_TXDMA_PAUSE;
con &= ~CON_TXDMA_ACTIVE;
}
if (other_tx_active(i2s)) {
writel(con, addr + I2SCON);
return;
}
if (!srp_active(i2s, IS_RUNNING)) {
printk(KERN_DEBUG
"%s: Turn Off - spr is no active\n", __func__);
con |= CON_TXCH_PAUSE;
if (any_rx_active(i2s))
mod |= MOD_RXONLY;
else
con &= ~CON_ACTIVE;
} else {
printk(KERN_DEBUG
"%s: Turn Off - spr is active\n", __func__);
}
}
writel(mod, addr + I2SMOD);
writel(con, addr + I2SCON);
}
/* RX Channel Control */
static void i2s_rxctrl(struct i2s_dai *i2s, int on)
{
void __iomem *addr = i2s->addr;
u32 con = readl(addr + I2SCON);
u32 mod = readl(addr + I2SMOD) & ~MOD_MASK;
if (on) {
con |= CON_RXDMA_ACTIVE | CON_ACTIVE;
con &= ~(CON_RXDMA_PAUSE | CON_RXCH_PAUSE);
if (any_tx_active(i2s))
mod |= MOD_TXRX;
else
mod |= MOD_RXONLY;
} else {
con |= CON_RXDMA_PAUSE | CON_RXCH_PAUSE;
con &= ~CON_RXDMA_ACTIVE;
if (any_tx_active(i2s))
mod |= MOD_TXONLY;
else
con &= ~CON_ACTIVE;
}
writel(mod, addr + I2SMOD);
writel(con, addr + I2SCON);
}
/* Flush FIFO of an interface */
static inline void i2s_fifo(struct i2s_dai *i2s, u32 flush, int stream)
{
void __iomem *fic;
u32 val;
if (!i2s)
return;
if (is_secondary(i2s))
fic = i2s->addr + I2SFICS;
else
fic = i2s->addr + I2SFIC;
/* Flush the FIFO */
writel(readl(fic) | flush, fic);
/* Be patient */
val = msecs_to_loops(1) / 1000; /* 1 usec */
while (--val)
cpu_relax();
writel(readl(fic) & ~flush, fic);
}
//会被 machine 中 hw_parames 函数调用
static int i2s_set_sysclk(struct snd_soc_dai *dai,
int clk_id, unsigned int rfs, int dir)
{
struct i2s_dai *i2s = to_info(dai);
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
u32 mod = readl(i2s->addr + I2SMOD);
switch (clk_id) {
case SAMSUNG_I2S_OPCLK:
mod &= ~MOD_OPCLK_MASK;
mod |= dir;
break;
case SAMSUNG_I2S_CDCLK:
/* Shouldn't matter in GATING(CLOCK_IN) mode */
if (dir == SND_SOC_CLOCK_IN)
rfs = 0;
if ((rfs && other->rfs && (other->rfs != rfs)) ||
(any_active(i2s) &&
(((dir == SND_SOC_CLOCK_IN)
&& !(mod & MOD_CDCLKCON)) ||
((dir == SND_SOC_CLOCK_OUT)
&& (mod & MOD_CDCLKCON))))) {
dev_err(&i2s->pdev->dev,
"%s:%d Other DAI busy\n", __func__, __LINE__);
return -EAGAIN;
}
if (dir == SND_SOC_CLOCK_IN)
mod |= MOD_CDCLKCON;
else
mod &= ~MOD_CDCLKCON;
i2s->rfs = rfs;
break;
case SAMSUNG_I2S_RCLKSRC_0: /* clock corrsponding to IISMOD[10] := 0 */
case SAMSUNG_I2S_RCLKSRC_1: /* clock corrsponding to IISMOD[10] := 1 */
if ((i2s->quirks & QUIRK_NO_MUXPSR)
|| (clk_id == SAMSUNG_I2S_RCLKSRC_0))
clk_id = 0;
else
clk_id = 1;
if (!any_active(i2s)) {
if (i2s->op_clk) {
if ((clk_id && !(mod & MOD_IMS_SYSMUX)) ||
(!clk_id && (mod & MOD_IMS_SYSMUX))) {
clk_put(i2s->op_clk);
} else {
i2s->rclk_srcrate =
clk_get_rate(i2s->op_clk);
return 0;
}
}
i2s->op_clk = clk_get(&i2s->pdev->dev,
i2s->src_clk[clk_id]);
if (IS_ERR(i2s->op_clk)) {
dev_err(&i2s->pdev->dev,
"failed to get i2s opclk\n");
return PTR_ERR(i2s->op_clk);
}
i2s->rclk_srcrate = clk_get_rate(i2s->op_clk);
/* Over-ride the other's */
if (other) {
other->op_clk = i2s->op_clk;
other->rclk_srcrate = i2s->rclk_srcrate;
}
} else if ((!clk_id && (mod & MOD_IMS_SYSMUX))
|| (clk_id && !(mod & MOD_IMS_SYSMUX))) {
dev_err(&i2s->pdev->dev,
"%s:%d Other DAI busy\n", __func__, __LINE__);
return -EAGAIN;
} else {
/* Call can't be on the active DAI */
i2s->op_clk = other->op_clk;
i2s->rclk_srcrate = other->rclk_srcrate;
return 0;
}
if (clk_id == 0)
mod &= ~MOD_IMS_SYSMUX;
else
mod |= MOD_IMS_SYSMUX;
break;
default:
dev_err(&i2s->pdev->dev, "We don't serve that!\n");
return -EINVAL;
}
writel(mod, i2s->addr + I2SMOD);
return 0;
}
//会被 machine 中 hw_parames 函数调用
static int i2s_set_fmt(struct snd_soc_dai *dai,
unsigned int fmt)
{
struct i2s_dai *i2s = to_info(dai);
u32 mod = readl(i2s->addr + I2SMOD);
u32 tmp = 0;
/* Format is priority */
switch (fmt & SND_SOC_DAIFMT_FORMAT_MASK) {
case SND_SOC_DAIFMT_RIGHT_J:
tmp |= MOD_LR_RLOW;
tmp |= MOD_SDF_MSB;
break;
case SND_SOC_DAIFMT_LEFT_J:
tmp |= MOD_LR_RLOW;
tmp |= MOD_SDF_LSB;
break;
case SND_SOC_DAIFMT_I2S:
tmp |= MOD_SDF_IIS;
break;
default:
dev_err(&i2s->pdev->dev, "Format not supported\n");
return -EINVAL;
}
/*
* INV flag is relative to the FORMAT flag - if set it simply
* flips the polarity specified by the Standard
*/
switch (fmt & SND_SOC_DAIFMT_INV_MASK) {
case SND_SOC_DAIFMT_NB_NF:
break;
case SND_SOC_DAIFMT_NB_IF:
if (tmp & MOD_LR_RLOW)
tmp &= ~MOD_LR_RLOW;
else
tmp |= MOD_LR_RLOW;
break;
default:
dev_err(&i2s->pdev->dev, "Polarity not supported\n");
return -EINVAL;
}
switch (fmt & SND_SOC_DAIFMT_MASTER_MASK) {
case SND_SOC_DAIFMT_CBM_CFM:
tmp |= MOD_SLAVE;
break;
case SND_SOC_DAIFMT_CBS_CFS:
/* Set default source clock in Master mode */
if (i2s->rclk_srcrate == 0)
i2s_set_sysclk(dai, SAMSUNG_I2S_RCLKSRC_0,
0, SND_SOC_CLOCK_IN);
break;
default:
dev_err(&i2s->pdev->dev, "master/slave format not supported\n");
return -EINVAL;
}
if (any_active(i2s) &&
((mod & (MOD_SDF_MASK | MOD_LR_RLOW
| MOD_SLAVE)) != tmp)) {
dev_err(&i2s->pdev->dev,
"%s:%d Other DAI busy\n", __func__, __LINE__);
return -EAGAIN;
}
mod &= ~(MOD_SDF_MASK | MOD_LR_RLOW | MOD_SLAVE);
mod |= tmp;
writel(mod, i2s->addr + I2SMOD);
return 0;
}
static int i2s_hw_params(struct snd_pcm_substream *substream,
struct snd_pcm_hw_params *params, struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
u32 mod = readl(i2s->addr + I2SMOD);
u32 con = readl(i2s->addr + I2SCON);
u32 stream = substream->stream;
if (!is_secondary(i2s))
mod &= ~(MOD_DC2_EN | MOD_DC1_EN);
switch (params_channels(params)) {
case 6:
mod |= MOD_DC1_EN | MOD_DC2_EN;
break;
case 4:
mod |= MOD_DC1_EN;
break;
case 2:
if (stream == SNDRV_PCM_STREAM_PLAYBACK)
i2s->dma_playback.dma_size = 4;
else
i2s->dma_capture.dma_size = 4;
break;
case 1:
if (stream == SNDRV_PCM_STREAM_PLAYBACK)
i2s->dma_playback.dma_size = 2;
else
i2s->dma_capture.dma_size = 2;
break;
default:
dev_err(&i2s->pdev->dev, "%d channels not supported\n",
params_channels(params));
return -EINVAL;
}
if (is_secondary(i2s))
mod &= ~MOD_BLCS_MASK;
else
mod &= ~MOD_BLCP_MASK;
if (is_manager(i2s))
mod &= ~MOD_BLC_MASK;
switch (params_format(params)) {
case SNDRV_PCM_FORMAT_S8:
if (is_secondary(i2s))
mod |= MOD_BLCS_8BIT;
else
mod |= MOD_BLCP_8BIT;
if (is_manager(i2s))
mod |= MOD_BLC_8BIT;
break;
case SNDRV_PCM_FORMAT_S16_LE:
if (is_secondary(i2s))
mod |= MOD_BLCS_16BIT;
else
mod |= MOD_BLCP_16BIT;
if (is_manager(i2s))
mod |= MOD_BLC_16BIT;
break;
case SNDRV_PCM_FORMAT_S24_LE:
if (is_secondary(i2s))
mod |= MOD_BLCS_24BIT;
else
mod |= MOD_BLCP_24BIT;
if (is_manager(i2s))
mod |= MOD_BLC_24BIT;
break;
default:
dev_err(&i2s->pdev->dev, "Format(%d) not supported\n",
params_format(params));
return -EINVAL;
}
if (is_secondary(i2s) || is_srp_enabled(i2s, stream)) {
mod |= MOD_TXS_IDMA;
con &= ~CON_FRXOFINTEN | ~CON_FTXSURINTEN | ~CON_FTXURINTEN;
}
writel(mod, i2s->addr + I2SMOD);
writel(con, i2s->addr + I2SCON);
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
snd_soc_dai_set_dma_data(dai, substream,
(void *)&i2s->dma_playback);
else
snd_soc_dai_set_dma_data(dai, substream,
(void *)&i2s->dma_capture);
i2s->frmclk = params_rate(params);
return 0;
}
static void i2s_reg_save(struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
u32 n, offset;
i2s->suspend_i2smod = readl(i2s->addr + I2SMOD);
i2s->suspend_i2scon = readl(i2s->addr + I2SCON);
i2s->suspend_i2spsr = readl(i2s->addr + I2SPSR);
if ((i2s->pdev->id == 0) || (i2s->pdev->id == SAMSUNG_I2S_SECOFF)) {
for (n = 0, offset = I2SAHB; offset <= I2SSTR1; offset += 4)
i2s->suspend_i2sahb[n++] = readl(i2s->addr + offset);
}
i2s->reg_saved = true;
dev_dbg(&i2s->pdev->dev, "Registers of I2S are saved\n");
return;
}
static void i2s_reg_restore(struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
u32 n, offset;
writel(i2s->suspend_i2smod, i2s->addr + I2SMOD);
writel(i2s->suspend_i2scon, i2s->addr + I2SCON);
writel(i2s->suspend_i2spsr, i2s->addr + I2SPSR);
if ((i2s->pdev->id == 0) || (i2s->pdev->id == SAMSUNG_I2S_SECOFF)) {
for (n = 0, offset = I2SAHB; offset <= I2SSTR1; offset += 4)
writel(i2s->suspend_i2sahb[n++], i2s->addr + offset);
}
i2s->reg_saved = false;
dev_dbg(&i2s->pdev->dev, "Registers of I2S are restored\n");
return;
}
static void i2s_clk_enable(struct i2s_dai *i2s, bool on)
{
if (on) {
if ((i2s->pdev->id == 0) ||
(i2s->pdev->id == SAMSUNG_I2S_SECOFF))
i2s->audss_clk_enable(true);
else
clk_enable(i2s->cclk);
} else {
if ((i2s->pdev->id == 0) ||
(i2s->pdev->id == SAMSUNG_I2S_SECOFF))
i2s->audss_clk_enable(false);
else
clk_disable(i2s->cclk);
}
}
/* We set constraints on the substream acc to the version of I2S */
static int i2s_startup(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
unsigned long flags;
spin_lock_irqsave(&lock, flags);
if (is_opened(i2s))
goto startup_exit;
/* Open dai */
i2s->mode |= DAI_OPENED;
if (is_manager(other))
i2s->mode &= ~DAI_MANAGER;
else
i2s->mode |= DAI_MANAGER;
/* Enforce set_sysclk in Master mode */
i2s->rclk_srcrate = 0;
#ifdef USE_ALT_REG_RECOVER
if (!is_opened(other) && !srp_active(i2s, IS_OPENED)) {
i2s_clk_enable(i2s, true);
/* Set default clk for I2S */
writel((MOD_OPCLK_PCLK | MOD_CDCLK_IN | MOD_RCLK_I2SCLK),
i2s->addr + I2SMOD);
}
#else
if (!is_opened(other)
#if defined(CONFIG_SND_SAMSUNG_RP)
&& !srp_active(i2s, IS_OPENED)
#endif
)
i2s_clk_enable(i2s, true);
if (i2s->reg_saved) {
if (is_opened(other))
i2s->reg_saved = false;
else
i2s_reg_restore(dai);
}
#endif
startup_exit:
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
i2s->tx_active = true;
else
i2s->rx_active = true;
spin_unlock_irqrestore(&lock, flags);
return 0;
}
static void i2s_shutdown(struct snd_pcm_substream *substream,
struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
unsigned long flags;
spin_lock_irqsave(&lock, flags);
/* disable stream_active */
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK)
i2s->tx_active = false;
else
i2s->rx_active = false;
if (i2s->tx_active || i2s->rx_active)
goto shutdown_exit;
/* Close dai */
i2s->mode &= ~DAI_OPENED;
i2s->mode &= ~DAI_MANAGER;
if (is_opened(other))
other->mode |= DAI_MANAGER;
/* Reset any constraint on RFS and BFS */
i2s->rfs = 0;
i2s->bfs = 0;
#ifdef USE_ALT_REG_RECOVER
if (!is_opened(other) && !srp_active(i2s, IS_OPENED))
i2s_clk_enable(i2s, false);
#else
if (!is_opened(other) && !srp_active(i2s, IS_RUNNING)) {
/* Gate CDCLK by default */
i2s_set_sysclk(dai, SAMSUNG_I2S_CDCLK, 0, SND_SOC_CLOCK_IN);
if (!i2s->reg_saved)
i2s_reg_save(dai);
}
if (!is_opened(other) && !srp_active(i2s, IS_OPENED))
i2s_clk_enable(i2s, false);
#endif
shutdown_exit:
spin_unlock_irqrestore(&lock, flags);
}
static int config_setup(struct i2s_dai *i2s)
{
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
unsigned rfs, bfs, blc;
u32 psr;
blc = get_blc(i2s);
bfs = i2s->bfs;
if (!bfs && other)
bfs = other->bfs;
/* Select least possible multiple(2) if no constraint set */
if (!bfs)
bfs = blc * 2;
rfs = i2s->rfs;
if (!rfs && other)
rfs = other->rfs;
if ((rfs == 256 || rfs == 512) && (blc == 24)) {
dev_err(&i2s->pdev->dev,
"%d-RFS not supported for 24-blc\n", rfs);
return -EINVAL;
}
if (!rfs) {
if (bfs == 16 || bfs == 32)
rfs = 256;
else
rfs = 384;
}
/* If already setup and running */
if (any_active(i2s) && (get_rfs(i2s) != rfs || get_bfs(i2s) != bfs)) {
dev_err(&i2s->pdev->dev,
"%s:%d Other DAI busy\n", __func__, __LINE__);
return -EAGAIN;
}
/* Don't bother RFS, BFS & PSR in Slave mode */
if (is_slave(i2s))
return 0;
set_bfs(i2s, bfs);
set_rfs(i2s, rfs);
if (!(i2s->quirks & QUIRK_NO_MUXPSR)) {
psr = i2s->rclk_srcrate / i2s->frmclk / rfs;
writel(((psr - 1) << 8) | PSR_PSREN, i2s->addr + I2SPSR);
dev_dbg(&i2s->pdev->dev,
"RCLK_SRC=%luHz PSR=%u, RCLK=%dfs, BCLK=%dfs\n",
i2s->rclk_srcrate, psr, rfs, bfs);
}
return 0;
}
/*
* Wait for the LR signal to allow synchronisation to the L/R clock
* from the codec. May only be needed for slave mode.
*/
static int i2s_lrsync(struct i2s_dai *i2s)
{
unsigned long loops = msecs_to_loops(5);
u32 con;
pr_debug("Entered %s\n", __func__);
while (--loops) {
con = readl(i2s->addr + I2SCON);
if (con & CON_LRINDEX)
break;
cpu_relax();
}
if (!loops) {
printk(KERN_ERR "%s: timeout\n", __func__);
printk(" I2SCON: %x, I2SMOD: %x, I2SPSR: %x\n",
readl(i2s->addr + I2SCON), readl(i2s->addr + I2SMOD),
readl(i2s->addr + I2SPSR));
printk("AUDSS_CLKSRC=%x, AUDSS_CLKDIV=%x, AUDSS_CLKGATE=%x\n",
readl(S5P_CLKSRC_AUDSS), readl(S5P_CLKDIV_AUDSS),
readl(S5P_CLKGATE_AUDSS));
printk("i2s pm info: reg_saved=%d, reg_saved_bypm=%d, sus-con=%x"
", sus-mod=%x, sus-psr=%x, tx_active=%d, rx_active=%d\n",
i2s->reg_saved, i2s->reg_saved_by_pm,
i2s->suspend_i2scon, i2s->suspend_i2smod, i2s->suspend_i2spsr,
i2s->tx_active, i2s->rx_active);
return -ETIMEDOUT;
}
return 0;
}
static int i2s_trigger(struct snd_pcm_substream *substream,
int cmd, struct snd_soc_dai *dai)
{
int capture = (substream->stream == SNDRV_PCM_STREAM_CAPTURE);
struct snd_soc_pcm_runtime *rtd = substream->private_data;
struct i2s_dai *i2s = to_info(rtd->cpu_dai);
unsigned long flags;
int ret = 0;
switch (cmd) {
case SNDRV_PCM_TRIGGER_START:
case SNDRV_PCM_TRIGGER_RESUME:
case SNDRV_PCM_TRIGGER_PAUSE_RELEASE:
if (is_slave(i2s)) {
ret = i2s_lrsync(i2s);
if (ret)
goto exit_err;
}
spin_lock_irqsave(&lock, flags);
if (config_setup(i2s)) {
spin_unlock_irqrestore(&lock, flags);
return -EINVAL;
}
if (capture)
i2s_rxctrl(i2s, 1);
else
i2s_txctrl(i2s, 1, substream->stream);//启动i2s 传输
spin_unlock_irqrestore(&lock, flags);
break;
case SNDRV_PCM_TRIGGER_STOP:
case SNDRV_PCM_TRIGGER_SUSPEND:
case SNDRV_PCM_TRIGGER_PAUSE_PUSH:
spin_lock_irqsave(&lock, flags);
if (capture)
i2s_rxctrl(i2s, 0);
else
i2s_txctrl(i2s, 0, substream->stream);
if (capture)
i2s_fifo(i2s, FIC_RXFLUSH, substream->stream);
else {
if (!srp_active(i2s, IS_RUNNING))
i2s_fifo(i2s, FIC_TXFLUSH, substream->stream);
}
spin_unlock_irqrestore(&lock, flags);
break;
}
exit_err:
return ret;
}
//会被 machine 中hw_parames 函数调用
static int i2s_set_clkdiv(struct snd_soc_dai *dai,
int div_id, int div)
{
struct i2s_dai *i2s = to_info(dai);
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
switch (div_id) {
case SAMSUNG_I2S_DIV_BCLK:
if ((any_active(i2s) && div && (get_bfs(i2s) != div))
|| (other && other->bfs && (other->bfs != div))) {
dev_err(&i2s->pdev->dev,
"%s:%d Other DAI busy\n", __func__, __LINE__);
return -EAGAIN;
}
i2s->bfs = div;
break;
default:
dev_err(&i2s->pdev->dev,
"Invalid clock divider(%d)\n", div_id);
return -EINVAL;
}
return 0;
}
static snd_pcm_sframes_t
i2s_delay(struct snd_pcm_substream *substream, struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
u32 reg = readl(i2s->addr + I2SFIC);
snd_pcm_sframes_t delay;
if (substream->stream == SNDRV_PCM_STREAM_CAPTURE)
delay = FIC_RXCOUNT(reg);
else if (is_secondary(i2s))
delay = FICS_TXCOUNT(readl(i2s->addr + I2SFICS));
else
delay = FIC_TXCOUNT(reg);
return delay;
}
#ifdef CONFIG_PM
static int i2s_suspend(struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
if (!i2s->reg_saved) {
i2s->audss_suspend();
i2s_reg_save(dai);
i2s->reg_saved_by_pm = true;
}
return 0;
}
static int i2s_resume(struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
#ifdef USE_ALT_REG_RECOVER
if (i2s->reg_saved) {
#else
if (i2s->reg_saved && i2s->reg_saved_by_pm) {
#endif
i2s_reg_restore(dai);
i2s->audss_resume();
i2s->reg_saved_by_pm = false;
}
return 0;
}
#else
#define i2s_suspend NULL
#define i2s_resume NULL
#endif
static int samsung_i2s_dai_probe(struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = to_info(dai);
struct i2s_dai *other = i2s->pri_dai ? : i2s->sec_dai;
i2s->addr = ioremap(i2s->base, 0x100);//映射寄存器
if (i2s->addr == NULL) {
dev_err(&i2s->pdev->dev, "cannot ioremap registers\n");
return -ENXIO;
}
if (is_secondary(i2s))
i2s->cclk = clk_get(&(i2s->pri_dai)->pdev->dev, "iis");
else
i2s->cclk = clk_get(&i2s->pdev->dev, "iis");//使用clk iis
if (IS_ERR(i2s->cclk)) {
pr_err("%s: failed to get cclk\n", __func__);
return PTR_ERR(i2s->cclk);
}
i2s_clk_enable(i2s, true);
if (i2s->quirks & QUIRK_NEED_RSTCLR)
writel(CON_RSTCLR, i2s->addr + I2SCON);
/* Reset any constraint on RFS and BFS */
i2s->rfs = 0;
i2s->bfs = 0;
i2s_txctrl(i2s, 0, 0);
i2s_fifo(i2s, FIC_TXFLUSH, 0);
if (!is_secondary(i2s)) {
i2s_rxctrl(i2s, 0);
i2s_fifo(i2s, FIC_RXFLUSH, 1);
}
if (is_secondary(i2s) || is_srp_enabled(i2s, 0))
idma_init((void *)i2s->addr);
/* Gate CDCLK by default */
if (!is_opened(other))
i2s_set_sysclk(dai, SAMSUNG_I2S_CDCLK,
0, SND_SOC_CLOCK_IN);
#ifdef USE_ALT_REG_RECOVER
#else
i2s_reg_save(dai);
#endif
i2s->reg_saved_by_pm = false;
i2s_clk_enable(i2s, false);
return 0;
}
static int samsung_i2s_dai_remove(struct snd_soc_dai *dai)
{
struct i2s_dai *i2s = snd_soc_dai_get_drvdata(dai);
if (i2s->quirks & QUIRK_NEED_RSTCLR)
writel(0, i2s->addr + I2SCON);
iounmap(i2s->addr);
return 0;
}
static struct snd_soc_dai_ops samsung_i2s_dai_ops = {
.trigger = i2s_trigger,
.hw_params = i2s_hw_params,
.set_fmt = i2s_set_fmt,
.set_clkdiv = i2s_set_clkdiv,
.set_sysclk = i2s_set_sysclk,
.startup = i2s_startup,
.shutdown = i2s_shutdown,
.delay = i2s_delay,
};
#define SAMSUNG_I2S_RATES SNDRV_PCM_RATE_8000_96000
#define SAMSUNG_I2S_FMTS (SNDRV_PCM_FMTBIT_S8 | \
SNDRV_PCM_FMTBIT_S16_LE | \
SNDRV_PCM_FMTBIT_S24_LE)
static __devinit
struct i2s_dai *i2s_alloc_dai(struct platform_device *pdev, bool sec)
{
struct i2s_dai *i2s;
i2s = kzalloc(sizeof(struct i2s_dai), GFP_KERNEL);
if (i2s == NULL)
return NULL;
i2s->pdev = pdev;
i2s->pri_dai = NULL;
i2s->sec_dai = NULL;
i2s->i2s_dai_drv.symmetric_rates = 1;
i2s->i2s_dai_drv.probe = samsung_i2s_dai_probe;
i2s->i2s_dai_drv.remove = samsung_i2s_dai_remove;
i2s->i2s_dai_drv.ops = &samsung_i2s_dai_ops;
i2s->i2s_dai_drv.suspend = i2s_suspend;
i2s->i2s_dai_drv.resume = i2s_resume;
i2s->i2s_dai_drv.playback.channels_min = 2;
i2s->i2s_dai_drv.playback.channels_max = 6;
i2s->i2s_dai_drv.playback.rates = SAMSUNG_I2S_RATES;
i2s->i2s_dai_drv.playback.formats = SAMSUNG_I2S_FMTS;
if (!sec) {
i2s->i2s_dai_drv.capture.channels_min = 1;
i2s->i2s_dai_drv.capture.channels_max = 2;
i2s->i2s_dai_drv.capture.rates = SAMSUNG_I2S_RATES;
i2s->i2s_dai_drv.capture.formats = SAMSUNG_I2S_FMTS;
} else { /* Create a new platform_device for Secondary */
i2s->pdev = platform_device_register_resndata(NULL,
pdev->name, pdev->id + SAMSUNG_I2S_SECOFF,
NULL, 0, NULL, 0);
if (IS_ERR(i2s->pdev)) {
kfree(i2s);
return NULL;
}
}
/* Pre-assign snd_soc_dai_set_drvdata */
dev_set_drvdata(&i2s->pdev->dev, i2s);
return i2s;
}
static __devinit int samsung_i2s_probe(struct platform_device *pdev)
{
u32 dma_pl_chan, dma_cp_chan, dma_pl_sec_chan;
struct i2s_dai *pri_dai, *sec_dai = NULL;
struct s3c_audio_pdata *i2s_pdata;
struct samsung_i2s *i2s_cfg;
struct resource *res;
u32 regs_base, quirks;
int ret = 0;
/* Call during Seconday interface registration */
if (pdev->id >= SAMSUNG_I2S_SECOFF) {
sec_dai = dev_get_drvdata(&pdev->dev);
snd_soc_register_dai(&sec_dai->pdev->dev,
&sec_dai->i2s_dai_drv);
return 0;
}
i2s_pdata = pdev->dev.platform_data;
if (i2s_pdata == NULL) {
dev_err(&pdev->dev, "Can't work without s3c_audio_pdata\n");
return -EINVAL;
}
res = platform_get_resource(pdev, IORESOURCE_DMA, 0);
if (!res) {
dev_err(&pdev->dev, "Unable to get I2S-TX dma resource\n");
return -ENXIO;
}
dma_pl_chan = res->start;//通过resource 来获得 dma_channel
res = platform_get_resource(pdev, IORESOURCE_DMA, 1);
if (!res) {
dev_err(&pdev->dev, "Unable to get I2S-RX dma resource\n");
return -ENXIO;
}
dma_cp_chan = res->start;
res = platform_get_resource(pdev, IORESOURCE_DMA, 2);
if (res)
dma_pl_sec_chan = res->start;
else
dma_pl_sec_chan = 0;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!res) {
dev_err(&pdev->dev, "Unable to get I2S SFR address\n");
return -ENXIO;
}
if (!request_mem_region(res->start, resource_size(res),
"samsung-i2s")) {
dev_err(&pdev->dev, "Unable to request SFR region\n");
return -EBUSY;
}
regs_base = res->start;
i2s_cfg = &i2s_pdata->type.i2s;
quirks = i2s_cfg->quirks;
pri_dai = i2s_alloc_dai(pdev, false);//会设置ops
if (!pri_dai) {
dev_err(&pdev->dev, "Unable to alloc I2S_pri\n");
ret = -ENOMEM;
goto err1;
}
pri_dai->dma_playback.dma_addr = regs_base + I2STXD;//dma的目的地址
pri_dai->dma_capture.dma_addr = regs_base + I2SRXD;
pri_dai->dma_playback.client =
(struct s3c2410_dma_client *)&pri_dai->dma_playback;
pri_dai->dma_capture.client =
(struct s3c2410_dma_client *)&pri_dai->dma_capture;
pri_dai->dma_playback.channel = dma_pl_chan;
pri_dai->dma_capture.channel = dma_cp_chan;
pri_dai->src_clk = i2s_cfg->src_clk;
pri_dai->dma_playback.dma_size = 4;
pri_dai->dma_capture.dma_size = 4;
pri_dai->base = regs_base;
pri_dai->quirks = quirks;
if (pdev->id == 0) {
pri_dai->audss_clk_enable = audss_clk_enable;
pri_dai->audss_suspend = audss_suspend;
pri_dai->audss_resume = audss_resume;
}
if (quirks & QUIRK_PRI_6CHAN)
pri_dai->i2s_dai_drv.playback.channels_max = 6;
if (quirks & QUIRK_SEC_DAI) {
sec_dai = i2s_alloc_dai(pdev, true);
if (!sec_dai) {
dev_err(&pdev->dev, "Unable to alloc I2S_sec\n");
ret = -ENOMEM;
goto err2;
}
sec_dai->dma_playback.dma_addr = regs_base + I2STXDS;
sec_dai->dma_playback.client =
(struct s3c2410_dma_client *)&sec_dai->dma_playback;
/* Use iDMA always if SysDMA not provided */
sec_dai->dma_playback.channel = dma_pl_sec_chan ? : -1;
sec_dai->src_clk = i2s_cfg->src_clk;
sec_dai->dma_playback.dma_size = 4;
sec_dai->base = regs_base;
sec_dai->quirks = quirks;
sec_dai->pri_dai = pri_dai;
pri_dai->sec_dai = sec_dai;
if (pdev->id == 0) {
sec_dai->audss_clk_enable = audss_clk_enable;
sec_dai->audss_suspend = audss_suspend;
sec_dai->audss_resume = audss_resume;
}
}
if (i2s_pdata->cfg_gpio && i2s_pdata->cfg_gpio(pdev)) {
dev_err(&pdev->dev, "Unable to configure gpio\n");
ret = -EINVAL;
goto err3;
}
snd_soc_register_dai(&pri_dai->pdev->dev, &pri_dai->i2s_dai_drv);
return 0;
err3:
kfree(sec_dai);
err2:
kfree(pri_dai);
err1:
release_mem_region(regs_base, resource_size(res));
return ret;
}
static __devexit int samsung_i2s_remove(struct platform_device *pdev)
{
struct i2s_dai *i2s, *other;
i2s = dev_get_drvdata(&pdev->dev);
other = i2s->pri_dai ? : i2s->sec_dai;
if (other) {
other->pri_dai = NULL;
other->sec_dai = NULL;
} else {
struct resource *res;
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (res)
release_mem_region(res->start, resource_size(res));
}
i2s->pri_dai = NULL;
i2s->sec_dai = NULL;
kfree(i2s);
snd_soc_unregister_dai(&pdev->dev);
return 0;
}
static struct platform_driver samsung_i2s_driver = {
.probe = samsung_i2s_probe,
.remove = samsung_i2s_remove,
.driver = {
.name = "samsung-i2s",
.owner = THIS_MODULE,
},
};
static int __init samsung_i2s_init(void)
{
return platform_driver_register(&samsung_i2s_driver);
}
module_init(samsung_i2s_init);
static void __exit samsung_i2s_exit(void)
{
platform_driver_unregister(&samsung_i2s_driver);
}
module_exit(samsung_i2s_exit);
/* Module information */
MODULE_AUTHOR("Jaswinder Singh, <[email protected]>");
MODULE_DESCRIPTION("Samsung I2S Interface");
MODULE_ALIAS("platform:samsung-i2s");
MODULE_LICENSE("GPL");
dma
static int dma_prepare(struct snd_pcm_substream *substream)
{
struct runtime_data *prtd = substream->runtime->private_data;
int ret = 0;
pr_debug("Entered %s\n", __func__);
/* return if this is a bufferless transfer e.g.
* codec <--> BT codec or GSM modem -- lg FIXME */
if (!prtd->params)
return 0;
/* channel needs configuring for mem=>device, increment memory addr,
* sync to pclk, half-word transfers to the IIS-FIFO. */
if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { //设置channel
s3c2410_dma_devconfig(prtd->params->channel,
S3C2410_DMASRC_MEM,
prtd->params->dma_addr); //dma_addr 为寄存器
} else {
s3c2410_dma_devconfig(prtd->params->channel,
S3C2410_DMASRC_HW,
prtd->params->dma_addr);
}
s3c2410_dma_config(prtd->params->channel,//设置大小
prtd->params->dma_size);
/* flush the DMA channel */
s3c2410_dma_ctrl(prtd->params->channel, S3C2410_DMAOP_FLUSH);
prtd->dma_loaded = 0;
prtd->dma_pos = prtd->dma_start;
/* enqueue dma buffers */
dma_enqueue(substream);
return ret;
}
static struct snd_pcm_ops dma_ops = {
.open = dma_open,
.close = dma_close,
.ioctl = snd_pcm_lib_ioctl,
.hw_params = dma_hw_params,
.hw_free = dma_hw_free,
.prepare = dma_prepare,
.trigger = dma_trigger,
.pointer = dma_pointer,
.mmap = dma_mmap,
};
//申请dma
static int preallocate_dma_buffer(struct snd_pcm *pcm, int stream)
{
struct snd_pcm_substream *substream = pcm->streams[stream].substream;
struct snd_dma_buffer *buf = &substream->dma_buffer;
size_t size = dma_hardware.buffer_bytes_max;
pr_debug("Entered %s\n", __func__);
buf->dev.type = SNDRV_DMA_TYPE_DEV;
buf->dev.dev = pcm->card->dev;
buf->private_data = NULL;
buf->area = dma_alloc_writecombine(pcm->card->dev, size,
&buf->addr, GFP_KERNEL);
if (!buf->area)
return -ENOMEM;
buf->bytes = size;
return 0;
}
static void dma_free_dma_buffers(struct snd_pcm *pcm)
{
struct snd_pcm_substream *substream;
struct snd_dma_buffer *buf;
int stream;
pr_debug("Entered %s\n", __func__);
for (stream = 0; stream < 2; stream++) {
substream = pcm->streams[stream].substream;
if (!substream)
continue;
buf = &substream->dma_buffer;
if (!buf->area)
continue;
dma_free_writecombine(pcm->card->dev, buf->bytes,
buf->area, buf->addr);
buf->area = NULL;
}
}
static u64 dma_mask = DMA_BIT_MASK(32);
//为playback 或者capture 申请dma mem
static int dma_new(struct snd_card *card,
struct snd_soc_dai *dai, struct snd_pcm *pcm)
{
int ret = 0;
pr_debug("Entered %s\n", __func__);
if (!card->dev->dma_mask)
card->dev->dma_mask = &dma_mask;
if (!card->dev->coherent_dma_mask)
card->dev->coherent_dma_mask = 0xffffffff;
if (dai->driver->playback.channels_min) {
ret = preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_PLAYBACK);
if (ret)
goto out;
}
if (dai->driver->capture.channels_min) {
ret = preallocate_dma_buffer(pcm,
SNDRV_PCM_STREAM_CAPTURE);
if (ret)
goto out;
}
out:
return ret;
}
struct snd_soc_platform_driver samsung_asoc_platform = {
.ops = &dma_ops,
.pcm_new = dma_new, //会在soc-core.c的soc_new_pcm 中进行调用
.pcm_free = dma_free_dma_buffers,
};数据传输的三个要素，源、目的、长度，在dma.c中都进行了设置。