I.mx6s上移植wm8960驱动（基于linux3.0.101版本）

I.mx6s上移植wm8960驱动
  此篇博文只记录移植的步骤，其他不做分析。首先上一张wm8960的硬件连接图：



1  上电操作

   配置wm8960的上电脚，文件位置：arch/arm/mach-mx6/board-mx6q_sabresd.c

#define SABRESD_CODEC_PWR_EN    IMX_GPIO_NR(7, 12)
440     /* Enable wm8960 power supply */
441     gpio_request(SABRESD_CODEC_PWR_EN, "audio-power");
442     gpio_direction_output(SABRESD_CODEC_PWR_EN, 1);
443     msleep(1);
444     gpio_set_value(SABRESD_CODEC_PWR_EN, 1);
445     printk("Power up wm8960 successful %s\n", __FUNCTION__);

另外，根据原理图可知上电脚为GPIO17，所以相关配置头文件里需将其配置为gpio口，文件位置：arch/arm/mach-mx6/board-mx6dl_sabresd.h

236     /* CODEC_PWR_EN */
237     MX6DL_PAD_GPIO_17__GPIO_7_12,

2：配置I2C，用于client的生成，文件位置：arch/arm/mach-mx6/board-mx6q_sabresd.c 需确认你的i2c是接的哪个控制器。

805 static struct i2c_board_info mxc_i2c0_board_info[] __initdata = {
806     {
807         I2C_BOARD_INFO("wm8960", 0x1a),
808     },
};

3: 修改wm8960  codec相关的数据结构，此处根据wm8962修改而来,文件位置：arch/arm/mach-mx6/board-mx6q_sabresd.c

以下是修改的地方

57 #include <sound/wm8962.h>
58 #include <sound/wm8960.h>

...省略部分内容...

410 static struct platform_device mx6_sabresd_audio_wm8960_device = {
411     .name = "imx-wm8960",
412 };
413
414 static struct mxc_audio_platform_data wm8960_data;
415
416 static int wm8960_clk_enable(int enable)
417 {
418     if (enable) {
419         clk_enable(clko);
420         printk("%s:wm clk enable\n", __FUNCTION__);
421     }
422     else {
423         clk_disable(clko);
424         printk("%s:wm clk disable\n", __FUNCTION__);
425     }
426     return 0;
427 }
428
429 static int mxc_wm8960_init(void)
430 {
431     int rate;
432
433     clko = clk_get(NULL, "clko_clk");
434     if (IS_ERR(clko)) {
435         pr_err("can't get CLKO clock.\n");
436         return PTR_ERR(clko);
437     }
438     /* both audio codec and comera use CLKO clk*/
439     rate = clk_round_rate(clko, 24000000);
440     clk_set_rate(clko, rate);
441
442     wm8960_data.sysclk = rate;
443
444     /* Enable wm8960 power supply */
445     gpio_request(SABRESD_CODEC_PWR_EN, "audio-power");
446     gpio_direction_output(SABRESD_CODEC_PWR_EN, 1);
447     msleep(1);
448     gpio_set_value(SABRESD_CODEC_PWR_EN, 1);
449     printk("%s:Power up wm8960 successful\n", __FUNCTION__);
450
451     return 0;
452 }
453
454 /* Note: we use struct wm8962_pdata for wm8960_config_data */
455 /* struct wm8962_pdata defind at linux/wm8962.h */
456 static struct wm8962_pdata wm8960_config_data = {
457     .gpio_init = {
458         [2] = WM8960_GPIO_FN_DMICCLK,
459         [4] = 0x8000 | WM8960_GPIO_FN_DMICDAT,
460     },
461     .clock_enable = wm8960_clk_enable,
462 };
463
464 static struct mxc_audio_platform_data wm8960_data = {
465     .ssi_num = 1,
466     .src_port = 2,
467     .ext_port = 3,
468     .hp_gpio = -1,                  //SABRESD_HEADPHONE_DET,
469 //  .hp_active_low = 1,
470     .mic_gpio = -1,                 //SABRESD_MICROPHONE_DET,
471 //  .mic_active_low = 1,
472     .init = mxc_wm8960_init,
473     .clock_enable = wm8960_clk_enable,
474 };
475
476 static struct regulator_consumer_supply sabresd_vwm8960_consumers[] = {
477     REGULATOR_SUPPLY("SPKVDD1", "0-001a"),
478     REGULATOR_SUPPLY("SPKVDD2", "0-001a"),
479 };
480
481 static struct regulator_init_data sabresd_vwm8960_init = {
482     .constraints = {
483         .name = "SPKVDD",
484         .valid_ops_mask =  REGULATOR_CHANGE_STATUS,
485         .boot_on = 1,
486     },
487     .num_consumer_supplies = ARRAY_SIZE(sabresd_vwm8960_consumers),
488     .consumer_supplies = sabresd_vwm8960_consumers,
489 };
490
491 static struct fixed_voltage_config sabresd_vwm8960_reg_config = {
492     .supply_name    = "SPKVDD",
493     .microvolts     = 4200000,
494     .gpio           = SABRESD_CODEC_PWR_EN,
495     .enable_high    = 1,
496     .enabled_at_boot = 1,
497     .init_data      = &sabresd_vwm8960_init,
498 };
499
500 static struct platform_device sabresd_vwm8960_reg_devices = {
501     .name   = "reg-fixed-voltage",
502     .id     = 4,
503     .dev    = {
504         .platform_data = &sabresd_vwm8960_reg_config,
505     },
506 };
...省略部分内容...

811 static struct i2c_board_info mxc_i2c0_board_info[] __initdata = {
812     {
813         I2C_BOARD_INFO("wm8960", 0x1a),
814     },
815     {
816         I2C_BOARD_INFO("ov564x", 0x3c),
817         .platform_data = (void *)&camera_data,
818     },
819     {
820         I2C_BOARD_INFO("mma8451", 0x1c),
821         .platform_data = (void *)&mma8451_position,
822     },
823 };
824
...省略部分内容...

1535 static int __init imx6q_init_audio(void)
1536 {
1537     if (board_is_mx6_reva()) {
1538         mxc_register_device(&mx6_sabresd_audio_wm8958_device,
1539                     &wm8958_data);
1540         imx6q_add_imx_ssi(1, &mx6_sabresd_ssi_pdata);
1541
1542         mxc_wm8958_init();
1543     } else {
1544         platform_device_register(&sabresd_vwm8960_reg_devices);
1545         mxc_register_device(&mx6_sabresd_audio_wm8960_device,
1546                     &wm8960_data);
1547         imx6q_add_imx_ssi(1, &mx6_sabresd_ssi_pdata);
1548
1549         mxc_wm8960_init();
1550         printk("%s\n", __FUNCTION__);
1551     }
1552
1553     return 0;
1554 }

...省略部分内容...

1859     if (board_is_mx6_reva()) {
1860         strcpy(mxc_i2c0_board_info[0].type, "wm8958");
1861         mxc_i2c0_board_info[0].platform_data = &wm8958_config_data;
1862     } else {
1863         strcpy(mxc_i2c0_board_info[0].type, "wm8960");
1864         mxc_i2c0_board_info[0].platform_data = &wm8960_config_data;
1865     }

4 修改wm8960.h：include/sound/wm8960.h

9 #ifndef _WM8960_PDATA_H
10 #define _WM8960_PDATA_H
11
12 #define WM8960_DRES_400R 0
13 #define WM8960_DRES_200R 1
14 #define WM8960_DRES_600R 2
15 #define WM8960_DRES_150R 3
16 #define WM8960_MAX_GPIO  6
17
18 #define WM8960_GPIO_FN_DMICCLK  19
19 #define WM8960_GPIO_FN_DMICDAT  20
20
21
22 struct wm8960_data {
23     bool capless;  /* Headphone outputs configured in capless mode */
24
25     int dres;  /* Discharge resistance for headphone outputs */
26
27     int gpio_base;
28     u32 gpio_init[WM8960_MAX_GPIO];
29
30     u32 mic_cfg;
31     bool irq_active_low;
32     bool spk_mono;
33 };
34
35 #endif

5 拷贝imx-wm8960.c到sound/soc/imx/目录下（获取地址：https://github.com/PDi-Communication-Systems-Inc/kernel-imx/blob/6bfe025386e4419a50b1b1d5a847a1329d1745cd/sound/soc/imx/imx-wm8960.c）

修改同目录下Kconfig，添加如下：

80 config SND_SOC_IMX_WM8960
81     tristate "SoC Audio support for IMX boards with WM8960"
82     select SND_MXC_SOC_MX2
83     select SND_SOC_WM8960
84     help
85       Say Y if you want to add support for SoC audio on an i.MX board with
86       a WM8960 codec.

修改同目录下Makefile：

18 snd-
4000
soc-imx-wm8960-objs := imx-wm8960.o
30 obj-$(CONFIG_SND_SOC_IMX_WM8960) += snd-soc-imx-wm8960.o

用make menuconfig配置上wm8960，编译下载至开发板即可进行验证。

 Ps ：一些调试命令及输出log：

root@imx6solo ~$ cat /proc/asound/cards
0 [wm8960audio    ]: wm8960-audio - wm8960-audio
wm8960-audio

还可以用  ls /dev/snd 看是否有相关节点，如有，则声卡驱动大致ok。下面接着介绍测试的先关方法

6  移植alsa-lib

 从官网（http://www.alsa-project.org/main/index.php/Download）下载 alsa-lib-1.0.29.tar.bz2包，
 6.1解压执行：

$ cd alsa-lib-1.0.29
$./configure --host=arm-none-linux-gnueabi --prefix=/home/***/alsa/alsa-lib

6.2 编译：

$ make

6.3 安装（需要root权限）

sudo make install

7 移植alsa-utils
从官网（http://www.alsa-project.org/main/index.php/Download）下载 alsa-utils-1.0.29.tar.bz2包，
7.1解压执行：

./configure --host=arm-none-linux-gnueabi --prefix=/home/**/alsa/alsa-utils --with-alsa-inc-prefix=/home/**/alsa/alsa-lib/include --with-alsa-prefix=/home/**/alsa/alsa-lib/lib --disable-alsamixer

注意上面最后的参数：--disable-alsamixer
若不加此参数编译会报错：configure
error required courses helper header not found 具体原因不清楚！！

7.2 编译

make

7.3安装（需要root权限）

sudo make install

8 开发板配置：
8.1 库的拷贝：

sudo cp alsa-lib/lib/libasound.* /home/**/rootfs/lib/

8.2  alsa-utils拷贝

将alsa-utils/bin目录小的内容拷贝到目标板根文件系统中的bin下

sudo cp alsa-utils/bin/* /home/**/rootfs/bin

8.3 alsa的配置文件拷贝
 除了库之外alsa的配置文件也需要拷贝到目标板根文件系统中,这里需要注意的是share目录在目标板的存放位置必须和在主机的存放路径一致！！

sudo cp -R **/alsa/alsa-lib/share/ /home/**/rootfs/**/alsa/alsa-lib/

重新挂载文件系统到目标板，通过 aplay 
-l可以查看我们的音频设备。

root@imx6solo ~$ aplay -L
null
Discard all samples (playback) or generate zero samples (capture)
root@imx6solo ~$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: wm8960audio [wm8960-audio], device 0: HiFi wm8960-hifi-0 []
Subdevices: 1/1
Subdevice #0: subdevice #0

播放声音文件：

aplay **.wav

最开始一直没有声音，后来发现是wm8960没有初始化的原因，所以要对其进行初始化：

初始化步骤：

第1步 设置power1 2 3；

第2步 设置时钟；

第3步 设置ADC-DAC,注意设置非静音；

第4步 设置audio interface；

第5步 设置volume；

第6步 设置mixer；

可参考如下代码(init at imx-wm8960.c:imx_hifi_hw_params
function)：

void wm8960_init(struct snd_soc_dai *codec_dai)
{
struct snd_soc_codec *codec = codec_dai->codec;

snd_soc_write(codec, 0x19, 0xc0); /* power1, ok*/
snd_soc_write(codec, 0x1a, 0x199); /* power2, ok*/

snd_soc_write(codec, 0x31, 0xf7); /* classd1 : enable L&R, ok */
snd_soc_write(codec, 0x33, 0x11b); /* classd3 : volume max, ok */

snd_soc_write(codec, 0x28, 0x179); /* ok */
snd_soc_write(codec, 0x29, 0x179); /* ok */

snd_soc_write(codec, 0x22, 0x100); /* dac to mixer, ok */
snd_soc_write(codec, 0x25, 0x100); /* dac to mixer, ok */

snd_soc_write(codec, 0x2f, 0x0c); /* left & right output mixer enable, ok */
snd_soc_write(codec, 0x05, 0x00); /* ok */
}