本文主要是介绍MTK LCM驱动移植,希望对大家解决编程问题提供一定的参考价值,需要的开发者们随着小编来一起学习吧!
对于LCM驱动移植,一般分为三部曲:
1、硬件IO口配置;
2、确保LCM背光能够正常点亮;
3、LCM驱动移植;
硬件电路:
1、GPIO配置
打开 mediatek\dct\DrvGen.exe
选择 mediatek\custom\xiaoxi\kernel\dct\dct\codegen.dws 配置文件
配置LCM PWM引脚、RST复位引脚、DISP_PWM引脚和LCM电源控制引脚
2、背光灯
编译烧录后启动系统,验证LCM背光是否能正常点亮,否则无法继续调试LCD;
3、LCM驱动移植(以ili9806e为例)
(1)、在mediatek\custom\common\kernel\lcm目录下创建ili9806目录,将驱动文件拷贝到驱动文件ili9806.c到新创建的目录中;代码自动将lcm软链接到mediatek\custom\common\lk和mediatek\custom\common\uboot目录,因此无需拷贝驱动文件到lk和uboot中;
(2)、修改\mediatek\custom\common\kernel\lcm\mt65xx_lcm_list.c, 在lcm_driver_list 数组中增加:
extern LCM_DRIVER ili9806e_lcm_drv;
#if defined(ILI9806)
&ili9806e_lcm_drv, //就是ili9488.c中的LCM_DRIVER结构
#endif
(3)、打开mediatek\config\prj\ProjectConfig.mk修改:
BUILD_LK=yes
CUSTOM_KERNEL_LCM=ili9806 //对应lcm目录驱动的子目录名
CUSTOM_LK_LCM=ili9806 //对应lcm目录驱动的子目录名
CUSTOM_UBOOT_LCM=ili9806 //对应lcm目录驱动的子目录名
LCM_WIDTH=480
LCM_HEIGHT=800
系统编译的时候,编译器会根据CUSTOM_KERNEL_LCM、CUSTOM_LK_LCM、CUSTOM_UBOOT_LCM找到mediatek\custom\common\kernel\lcm\ili9806目录,拷贝mediatek\custom\out\pro\kernel\lcm目录,参与系统的编译,所以对于驱动文件名有没命名要求;lk和uboot同理;
注:系统此时也会产生ILI9806的环境变量,这就是mt65xx_lcm_list.c中的 #if defined(ILI9806) 可以进行预编译处理;
4、LCM驱动简要解析
LCM_DRIVER结构表示一个LCM对象,里边包含LCM各项参数;
LCM_DRIVER ili9806e_drv =
{.name = "ili9806e_txd_dsi_cmd_sp13_lcm_drv", //设备名.set_util_funcs = lcm_set_util_funcs, //获取LCM_DRIVER结构.get_params = lcm_get_params, //获取lcm参数.init = lcm_init, //lcm初始化函数.suspend = lcm_suspend, //lcm挂起.resume = lcm_resume, //lcm恢复.compare_id = lcm_compare_id, //设备id匹配
};
以上函数接口是为MTK框架中的几个重要接口;
/* 获取设备的LCM_DRIVER结构 */
static void lcm_set_util_funcs(const LCM_UTIL_FUNCS *util)
{memcpy(&lcm_util, util, sizeof(LCM_UTIL_FUNCS));
}/* 获取lcm各个参数 */
static void lcm_get_params(LCM_PARAMS *params)
{memset(params, 0, sizeof(LCM_PARAMS)); //先将LCM_PARAMS结构清空params->type = LCM_TYPE_DSI; //lcm接口类型params->width = FRAME_WIDTH; //lcm显示宽度params->height = FRAME_HEIGHT; //lcm显示高度/* 设置通信模式 */// enable tearing-freeparams->dbi.te_mode = LCM_DBI_TE_MODE_DISABLED;params->dbi.te_edge_polarity = LCM_POLARITY_RISING;/* dsi分两种模式,一种是cmd模式,一种是video模式 */
#if (LCM_DSI_CMD_MODE)params->dsi.mode = CMD_MODE;
#elseparams->dsi.mode = SYNC_PULSE_VDO_MODE;
#endif/* 设置数据格式 */// DSI/* Command mode setting */params->dsi.LANE_NUM = LCM_TWO_LANE; //两通道MIPI//The following defined the fomat for data coming from LCD engine.params->dsi.data_format.color_order = LCM_COLOR_ORDER_RGB; params->dsi.data_format.trans_seq = LCM_DSI_TRANS_SEQ_MSB_FIRST;params->dsi.data_format.padding = LCM_DSI_PADDING_ON_LSB;params->dsi.data_format.format = LCM_DSI_FORMAT_RGB888; // Highly depends on LCD driver capability.// Not support in MT6573params->dsi.packet_size = 256;// Video mode settingparams->dsi.intermediat_buffer_num = 0;params->dsi.PS = LCM_PACKED_PS_24BIT_RGB888;params->dsi.word_count = 480 * 3;/* 垂直参数设置 */params->dsi.vertical_sync_active = 4; //垂直同步信号的宽度params->dsi.vertical_backporch = 16;//10 //垂直同步信号的后沿params->dsi.vertical_frontporch = 20;//8 //垂直同步信号的前沿params->dsi.vertical_active_line = FRAME_HEIGHT;/* 水平参数设置 */params->dsi.horizontal_sync_active = 10; //水平同步信号的宽度params->dsi.horizontal_backporch = 50; //水平同步信号的后沿params->dsi.horizontal_frontporch = 60; //水平同步信号的前沿params->dsi.horizontal_active_pixel = FRAME_WIDTH;/* 时钟频率 */params->dsi.PLL_CLOCK= 200;
}
//复位引脚
#define SET_RESET_PIN(v) (lcm_util.set_reset_pin((v))) //这里就会直接使用GPIO_LCD_RST硬引脚
//延时函数
#define UDELAY(n) (lcm_util.udelay(n))
#define MDELAY(n) (lcm_util.mdelay(n))
//long packet 操作接口
#define dsi_set_cmdq_V3(para_tbl, size, force_update) lcm_util.dsi_set_cmdq_V3(para_tbl, size, force_update) //para_tbl:LCM_setting_table结构, size:大小, force_update:强制更新标志
#define dsi_set_cmdq_V2(cmd, count, ppara, force_update) lcm_util.dsi_set_cmdq_V2(cmd, count, ppare, force_update) //cmd:命令, count:大小, ppara:参数,force_update:强制更新标志
//short packet 操作接口
#define dsi_set_cmdq(pdata, queue_size, force_update) lcm_util.dsi_set_cmdq(pdata, queue_size, force_update)
//读写寄存器等操作
#define write_cmd(cmd) lcm_util.dsi_write_cmd(cmd)
#define write_regs(addr, pdata, byte_nums) lcm_util.dsi_write_regs(addr, pdata, bytes_nums)
#define read_reg(cmd) lcm_util.dsi_dcs_read_lcm_reg(cmd)
#define read_reg_v2(cmd, buffer, buffer_size) lcm_util.dsi_dcs_read_lcm_reg_v2(cmd, buffer, buffer_size)
/* 初始化参数及函数接口 */
static struct LCM_setting_table lcm_initialization_setting[] = {/* 数据格式:命令,数据个数,数据 */ //命令一般是对应寄存器地址{0xFF, 5,{0xFF,0x98,0x06,0x04,0x01}}, {0x08, 1, {0x10}},{0x21, 1, {0x01}},{0x30, 1, {0x02}},{0x31, 1, {0x02}},{0x40, 1, {0x16}}, {0x41, 1, {0x22}}, ......{0x53, 1, {0x1A}}, //10 {0xFF, 5,{0xFF,0x98,0x06,0x04,0x07}},{0x17, 1, {0x12}}, //22{0x02, 1, {0x77}},{0xFF, 5,{0xFF,0x98,0x06,0x04,0x00}},{0x35,1, {0x00}},{0x36,1, {0x03}}, //翻转180度{0x11, 1, {0x00}},{REGFLAG_DELAY, 120, {}},{0x29, 1, {0x00}},{REGFLAG_DELAY, 50, {}},{REGFLAG_END_OF_TABLE, 0x00, {}} //数据结束必须使用REGFLAG_END_OF_TABLE
};static void lcm_init(void)
{
/* 复位 */SET_RESET_PIN(1); MDELAY(10);SET_RESET_PIN(0);/* Third change Lava */MDELAY(10);//10 SET_RESET_PIN(1);MDELAY(120); // 150/* 初始化数据 */push_table(lcm_initialization_setting, sizeof(lcm_initialization_setting) / sizeof(struct LCM_setting_table), 1);
}
/* 设备挂起 */
static void lcm_suspend(void)
{
#ifdef BUILD_LK printf("%s, ALS/PS bbbbbbbbbbbbbbb \n", __func__);
#elseprintk("%s, ALS/PS bbbbbbbbbbbbbb \n", __func__);
#endif push_table(lcm_deep_sleep_mode_in_setting, sizeof(lcm_deep_sleep_mode_in_setting) / sizeof(struct LCM_setting_table), 1);SET_RESET_PIN(0);MDELAY(20);//10 SET_RESET_PIN(1);MDELAY(50);
}
因为lcm驱动被映射到lk层,在lk层只能使用printf进行调试,但在kernel层中只能printk进行打印调试,所以可以使用宏进行BUILD_LK区分;
挂起的机制一般有两种:简单睡眠或深度睡眠;
简单睡眠:设备还处于工作状态,可以被唤醒,但是此时也会存在待机功耗等问题;
深度睡眠:设备处于休眠状态,基本处于不工作状态,因此无法被唤醒;
一般程序设计都是使用深度睡眠,在唤醒时进行重新初始化;
/* 设备恢复 */
static void lcm_resume(void)
{lcm_init();//push_table(lcm_sleep_out_setting, sizeof(lcm_sleep_out_setting) / sizeof(struct LCM_setting_table), 1);
}
重新初始化设备
/* 设备id匹配 */
static unsigned int lcm_compare_id()
{unsigned int array[4];unsigned char buffer[4] = {0,0,0,0};unsigned char id_high=0;unsigned char id_low=0;unsigned char id_low0=0;unsigned int id=0;/* 先进行复位操作 */SET_RESET_PIN(1);MDELAY(10);SET_RESET_PIN(0);MDELAY(10);SET_RESET_PIN(1);MDELAY(200);//*************Enable CMD2 Page1 *******************//array[0]=0x00063902;array[1]=0x0698ffff;array[2]=0x00000104;dsi_set_cmdq(array, 3, 1);array[0] = 0x00043700;dsi_set_cmdq(array, 1, 1);MDELAY(10);read_reg_v2(0x00, buffer, 4);id_high = buffer[0]; //98array[0] = 0x00043700;dsi_set_cmdq(array, 1, 1);MDELAY(10);read_reg_v2(0x01, buffer, 4);id_low = buffer[0]; //06array[0] = 0x00043700;dsi_set_cmdq(array, 1, 1);MDELAY(10);read_reg_v2(0x02, buffer, 4);id_low0 = buffer[0]; //04id = (id_high<<16) | (id_low<<8)|id_low0;#ifdef BUILD_LKprintf("ILI9806e:id2=%x.\n",id);printf("ILI9806e:id4=%x.\n",id_high);printf("ILI9806e:id5=%x.\n",id_low);printf("ILI9806e:id5=%x.\n",id_low0);
#elseprintk("ILI9806e:id=%x.\n",id);printk("ILI9806e:id_high=%x.\n",id_high);printk("ILI9806e:id_low=%x.\n",id_low);printk("ILI9806e:id_low=%x.\n",id_low0);
#endifreturn (0x980604 == id) ? 1 : 0;
}
数据编写格式是遵循MIPI协议进行编写的
注:如果系统只配置一个lcm设备,lcm_compare_id接口不会调用,只有系统存在多个设备的是才会调用该接口进行匹配;
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