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335xd添加按键

2018-5-22 11:09| 发布者: 飞凌-chongzi| 查看: 2172| 评论: 0

类目： AM335x系列产品 > Linux 文档编号: 185

目前有客户咨询335x系列的开发板上的按键设备名keypad是怎样生成的，因为在内核驱动中找不到相对应的名字。

在内核中按键的名字使用的是gpio-keys,然后在文件系统中进行了一个系统连接名字就变成了keypad.

具体的文件是/etc/udev/rules.d/local.rules文件

该文件中的以下语句就是生成keypad的链接命令

# Create a symlink to any gpio-keys input device

SUBSYSTEM=="input", KERNEL=="event[0-9]*", ATTRS{name}=="gpio-keys", SYMLINK+="input/keypad"

########################################################################

335按键添加方法

******************************************************************

arch/arm/mach-omap2/board-am335xevm.c

static struct pinmux_config gpio_keys_pin_mux_forlinx[] = {

#if defined(CONFIG_OK335XD)

{"gpmc_a4.gpio1_20", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a5.gpio1_21", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a6.gpio1_22", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a7.gpio1_23", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a8.gpio1_24", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a9.gpio1_25", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

#elif defined(CONFIG_OK335XS)

{"xdma_event_intr0.gpio0_19", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_csn3.gpio2_0", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"mcasp0_fsx.gpio3_15", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_csn1.gpio1_30", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"mcasp0_aclkx.gpio3_14", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

#elif defined(CONFIG_OK335XS2)

{"gpmc_a4.gpio1_20", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a5.gpio1_21", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

{"gpmc_a6.gpio1_22", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

#endif

{NULL, 0},

};

++此处添加自己按键的pinmux定义++

{"gpmc_a10.gpio1_26", OMAP_MUX_MODE7 | AM33XX_PIN_INPUT},

===========================================================

static void keys_init(int evm_id, int profile)

{

int err;

setup_pin_mux(gpio_keys_pin_mux_forlinx);

err = platform_device_register(&am335x_evm_gpio_keys_forlinx);

if (err)

pr_err("failed to register gpio key device\n");

}

static struct platform_device am335x_evm_gpio_keys_forlinx = {

.name = "gpio-keys",

.id = -1,

.dev = {

.platform_data = &am335x_evm_gpio_key_info_forlinx,

};

static struct gpio_keys_platform_data am335x_evm_gpio_key_info_forlinx = {

.buttons = am335x_evm_gpio_buttons_forlinx,

.nbuttons = ARRAY_SIZE(am335x_evm_gpio_buttons_forlinx),

};

static struct gpio_keys_button am335x_evm_gpio_buttons_forlinx[] = {

#if defined(CONFIG_OK335XD)

{

.code = BTN_0,

.gpio = GPIO_TO_PIN(1, 20),

.desc = "SW1",

{

.code = BTN_1,

.gpio = GPIO_TO_PIN(1, 21),

.desc = "SW2",

{

.code = BTN_2,

.gpio = GPIO_TO_PIN(1, 22),

.desc = "SW3",

.wakeup = 1,

{

.code = BTN_3,

.gpio = GPIO_TO_PIN(1, 23),

.desc = "SW4",

{

.code = BTN_4,

.gpio = GPIO_TO_PIN(1, 24),

.desc = "SW5",

.wakeup = 1,

{

.code = BTN_5,

.gpio = GPIO_TO_PIN(1, 25),

.desc = "SW6",

++此处添加自己gpio对应按键定义++

{

.code = BTN_6,

.gpio = GPIO_TO_PIN(1, 26),

.desc = "SW7",

===========================================================

#elif defined(CONFIG_OK335XS)

{

.code = BTN_0,

.gpio = GPIO_TO_PIN(0, 19),

.desc = "SW1",

{

.code = BTN_1,

.gpio = GPIO_TO_PIN(2, 0),

.desc = "SW2",

{

.code = BTN_2,

.gpio = GPIO_TO_PIN(3, 15),

.desc = "SW3",

.wakeup = 1,

{

.code = BTN_3,

.gpio = GPIO_TO_PIN(1, 30),

.desc = "SW4",

{

.code = BTN_4,

.gpio = GPIO_TO_PIN(3, 14),

.desc = "SW5",

.wakeup = 1,

#elif defined(CONFIG_OK335XS2)

{

.code = BTN_0,

.gpio = GPIO_TO_PIN(1, 20),

.desc = "SW1",

{

.code = BTN_1,

.gpio = GPIO_TO_PIN(1, 21),

.desc = "SW2",

{

.code = BTN_2,

.gpio = GPIO_TO_PIN(1, 22),

.desc = "SW3",

.wakeup = 1,

#endif

};

至此按键添加完毕，但事情是否做完了呢，还没有，我们用到了gpmc_a10这个管脚，需要将其他用到这个引脚的地方注释掉，保证没有其他功能占用

检测了一下gpmc_a10这个脚有一些其他的pinmux定义，但是都没完成初始化，不会产生影响

ps：

{

.code = BTN_0,

.gpio = GPIO_TO_PIN(1, 20),

.desc = "SW1",

这个BTN_0指的是什么呢，这需要看一下include/linux/input.h，这里定义了按键的键值

已解决

未解决

只是看看

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335xd添加按键

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