linux uart驱动——uart platfrom 注册（三）

一：注册platform device

注册一个platfrom device一般需要初始化两个内容，设备占用的资源resource和设备私有数据dev.platfrom_data。设备的resource占用的资源主要包含两个方面：IO内存和IRQ资源信息，有时也包含DMA。

resource结构： 

   1:  struct resource {
   2:      resource_size_t start;//定义资源的起始地址 
   3:      resource_size_t end;//定义资源的结束地址
   4:      const char *name;//定义资源的名称 
   5:      unsigned long flags;//定义资源的类型，比如MEM，IO，IRQ，DMA类型
   6:      struct resource *parent, *sibling, *child;//资源链表指针 
   7:  };

笔者当前的君正board有三个串口： 

   1:  #ifdef CONFIG_SERIAL_JZ47XX_UART0
   2:  /* UART ( uart controller) */
   3:  static struct resource jz_uart0_resources[] = {
   4:      [0] = {
   5:          .start          = UART0_IOBASE,
   6:          .end            = UART0_IOBASE + 0x1000 - 1,
   7:          .flags          = IORESOURCE_MEM,
   8:      },
   9:      [1] = {
  10:          .start          = IRQ_UART0,
  11:          .end            = IRQ_UART0,
  12:          .flags          = IORESOURCE_IRQ,
  13:      },
  14:  #ifdef CONFIG_SERIAL_JZ47XX_UART0_DMA
  15:      [2] = {
  16:          .start          = JZDMA_REQ_UART0,
  17:          .flags          = IORESOURCE_DMA,
  18:      },
  19:  #endif
  20:  };
  21:   
  22:  struct platform_device jz_uart0_device = {
  23:      .name = "jz-uart",
  24:      .id = 0,
  25:      .num_resources  = ARRAY_SIZE(jz_uart0_resources),
  26:      .resource       = jz_uart0_resources,
  27:  };
  28:  #endif
  29:  #ifdef CONFIG_SERIAL_JZ47XX_UART1
  30:  static struct resource jz_uart1_resources[] = {
  31:      [0] = {
  32:          .start          = UART1_IOBASE,
  33:          .end            = UART1_IOBASE + 0x1000 - 1,
  34:          .flags          = IORESOURCE_MEM,
  35:      },
  36:      [1] = {
  37:          .start          = IRQ_UART1,
  38:          .end            = IRQ_UART1,
  39:          .flags          = IORESOURCE_IRQ,
  40:      },
  41:  #ifdef CONFIG_SERIAL_JZ47XX_UART1_DMA
  42:      [2] = {
  43:          .start          = JZDMA_REQ_UART1,
  44:          .flags          = IORESOURCE_DMA,
  45:      },
  46:  #endif
  47:  };
  48:  struct platform_device jz_uart1_device = {
  49:      .name = "jz-uart",
  50:      .id = 1,
  51:      .num_resources  = ARRAY_SIZE(jz_uart1_resources),
  52:      .resource       = jz_uart1_resources,
  53:  };
  54:  #endif
  55:  #ifdef CONFIG_SERIAL_JZ47XX_UART2
  56:  static struct resource jz_uart2_resources[] = {
  57:      [0] = {
  58:          .start          = UART2_IOBASE,
  59:          .end            = UART2_IOBASE + 0x1000 - 1,
  60:          .flags          = IORESOURCE_MEM,
  61:      },
  62:      [1] = {
  63:          .start          = IRQ_UART2,
  64:          .end            = IRQ_UART2,
  65:          .flags          = IORESOURCE_IRQ,
  66:      },
  67:  #ifdef CONFIG_SERIAL_JZ47XX_UART2_DMA
  68:      [2] = {
  69:          .start          = JZDMA_REQ_UART2,
  70:          .flags          = IORESOURCE_DMA,
  71:      },
  72:  #endif
  73:  };
  74:   
  75:  struct platform_device jz_uart2_device = {
  76:      .name = "jz-uart",
  77:      .id = 2,
  78:      .num_resources  = ARRAY_SIZE(jz_uart2_resources),
  79:      .resource       = jz_uart2_resources,
  80:  };
  81:  #endif

platform_device_register(&jz_uartXX_device);

注册成功后：（多个device）

ls /sys/bus/platform/devices/
jz-uart.0/  jz-uart.2/

 

二：注册platfrom driver

   1:  /* serial platfrom driver */
   2:  static struct platform_driver serial_jz47xx_driver = {
   3:      .probe          = serial_jz47xx_probe,
   4:      .remove         = serial_jz47xx_remove,
   5:   
   6:      .driver        = {
   7:          .name    = "jz-uart",
   8:          .owner    = THIS_MODULE,
   9:  #ifdef CONFIG_PM
  10:          .pm    = &serial_jz47xx_pm_ops,
  11:  #endif
  12:      },
  13:  };
  14:   
  15:  int __init serial_jz47xx_init(void)
  16:  {
  17:      int ret;
  18:      /* 功能：uart_register_driver用于将串口驱动uart_driver注册到内核(串口核心层)中，
  19:                  通常在模块初始化函数调用该函数。
  20:        * 参数 drv：要注册的uart_driver
  21:        * 返回值：  成功，返回0；否则返回错误码
  22:       */
  23:      ret = uart_register_driver(&serial_jz47xx_reg);
  24:      if (ret != 0)
  25:          return ret;
  26:   
  27:      /* 注册serial platfrom驱动 */
  28:      ret = platform_driver_register(&serial_jz47xx_driver); 
  29:      if (ret != 0)
  30:          uart_unregister_driver(&serial_jz47xx_reg);
  31:   
  32:      return ret;
  33:  }
  34:   
  35:  void __exit serial_jz47xx_exit(void)
  36:  {
  37:      platform_driver_unregister(&serial_jz47xx_driver);
  38:      uart_unregister_driver(&serial_jz47xx_reg);
  39:  }
  40:   
  41:   
  42:  #ifdef CONFIG_EARLY_INIT_RUN
  43:  rootfs_initcall(serial_jz47xx_init);/*先于module注册*/
  44:   
  45:  #else
  46:  module_init(serial_jz47xx_init);
  47:   
  48:  #endif
  49:   
  50:  module_exit(serial_jz47xx_exit);
  51:   
  52:  MODULE_LICENSE("GPL");
  53:  MODULE_ALIAS("platform:jz47xx-uart");

注册成功后：（一个driver对应多个device）

ls /sys/bus/platform/drivers/jz-uart/
bind       jz-uart.0  jz-uart.2  uevent     unbind

posted @ 2016-11-10 14:06  夕相待  阅读(2388)  评论(0)    收藏  举报