drivers/input/misc/rk_board_id.c

   1 #include <linux/kernel.h>\r
   2 #include <linux/init.h>\r
   3 #include <linux/platform_device.h>\r
   4 #include <linux/input.h>\r
   5 #include <linux/io.h>\r
   6 #include <linux/delay.h>\r
   7 #include <linux/i2c.h>\r
   8 #include <linux/skbuff.h>\r
   9 \r
  10 #include <mach/board.h>\r
  11 #include <mach/io.h>\r
  12 #include <mach/gpio.h>\r
  13 #include <mach/iomux.h>\r
  14 \r
  15 #include <linux/rk_board_id.h>\r
  16 #if 0\r
  17 #define DBG(x...)  printk(x)\r
  18 #else\r
  19 #define DBG(x...)\r
  20 #endif\r
  21 \r
  22 extern void kernel_restart(char *cmd);\r
  23 \r
  24 struct board_id_private_data {\r
  25         struct mutex id_mutex;\r
  26         int last_value[16];\r
  27         int board_id;\r
  28         struct board_id_platform_data *pdata;\r
  29 };\r
  30 \r
  31 static struct board_id_private_data *g_id;\r
  32 \r
  33 \r
  34 enum rk_board_id rk_get_board_id(void)\r
  35 {\r
  36         struct board_id_private_data *id = g_id;\r
  37         DBG("%s:id:0x%x\n",__func__,id->board_id);\r
  38         return id->board_id;\r
  39 }\r
  40 EXPORT_SYMBOL(rk_get_board_id);\r
  41 \r
  42 static int _rk_get_board_id(struct board_id_private_data *id)\r
  43 {\r
  44         int result = 0;\r
  45         int value1 = 0, value2 = 0, value3 = 0;\r
  46         int i = 0, j = 0;\r
  47         \r
  48         id->board_id = -1;\r
  49                         \r
  50         for(i=0; i<id->pdata->num_gpio; i++)\r
  51         {\r
  52                 gpio_request(id->pdata->gpio_pin[i],"gpio_board_id");\r
  53                 gpio_direction_input(id->pdata->gpio_pin[i]);\r
  54                 gpio_pull_updown(id->pdata->gpio_pin[i], PullDisable);\r
  55                 for(j=0; j<1000; j++)\r
  56                 {\r
  57                         value1 = gpio_get_value(id->pdata->gpio_pin[i]);\r
  58                         if(value1 < 0)\r
  59                                 continue;\r
  60                         mdelay(1);\r
  61                         value2 = gpio_get_value(id->pdata->gpio_pin[i]);\r
  62                         if(value2 < 0)\r
  63                                 continue;\r
  64                         mdelay(1);\r
  65                         value3 = gpio_get_value(id->pdata->gpio_pin[i]);\r
  66                         if(value3 < 0)\r
  67                                 continue;\r
  68                         if((value1 == value2) && (value2 == value3))\r
  69                                 break;\r
  70                 }\r
  71                 if(j >= 1000)\r
  72                 {\r
  73                         printk("%s:hareware error,gpio level changed always!\n");                       \r
  74                         kernel_restart(NULL);\r
  75                 }\r
  76                 \r
  77                 result = (value1 << i) | result;\r
  78                 \r
  79                 DBG("%s:gpio:%d,value:%d\n",__func__,id->pdata->gpio_pin[i],value1);\r
  80         }\r
  81 \r
  82         id->board_id = result;\r
  83 \r
  84         \r
  85         DBG("%s:num=%d,id=0x%x\n",__func__,id->pdata->num_gpio, id->board_id);\r
  86 \r
  87         return result;\r
  88 }\r
  89 \r
  90 \r
  91 static int __devinit rk_board_id_probe(struct platform_device *pdev)\r
  92 {\r
  93         struct board_id_platform_data *pdata = pdev->dev.platform_data;\r
  94         struct board_id_private_data *id = NULL;\r
  95         int result = 0;\r
  96 \r
  97         if(!pdata)\r
  98                 return -ENOMEM;\r
  99         \r
 100         id = kzalloc(sizeof(struct board_id_private_data), GFP_KERNEL);\r
 101         if (id == NULL) {\r
 102                 dev_err(&pdev->dev, "Unable to allocate private data\n");\r
 103                 return -ENOMEM;\r
 104         }\r
 105 \r
 106         id->pdata = pdata;\r
 107         \r
 108         if(pdata->init_platform_hw)\r
 109                 pdata->init_platform_hw();\r
 110         \r
 111         result = _rk_get_board_id(id);\r
 112 \r
 113         if(pdata->init_parameter)\r
 114                 pdata->init_parameter(id->board_id);\r
 115 \r
 116         if(pdata->exit_platform_hw)\r
 117                 pdata->exit_platform_hw();\r
 118         \r
 119         platform_set_drvdata(pdev, id); \r
 120         g_id = id;\r
 121         \r
 122         printk("%s:board id :0x%x\n",__func__,result);\r
 123         return 0;\r
 124 }\r
 125 \r
 126 static int __devexit rk_board_id_remove(struct platform_device *pdev)\r
 127 {\r
 128         //struct board_id_platform_data *pdata = pdev->dev.platform_data;\r
 129         struct board_id_private_data *id = platform_get_drvdata(pdev);\r
 130         \r
 131         kfree(id);\r
 132         \r
 133         return 0;\r
 134 }\r
 135 \r
 136 static struct platform_driver rk_board_id_driver = {\r
 137         .probe          = rk_board_id_probe,\r
 138         .remove         = __devexit_p(rk_board_id_remove),\r
 139         .driver         = {\r
 140                 .name   = "rk-board-id",\r
 141                 .owner  = THIS_MODULE,\r
 142         },\r
 143 };\r
 144 \r
 145 static int __init rk_get_board_init(void)\r
 146 {\r
 147         return platform_driver_register(&rk_board_id_driver);\r
 148 }\r
 149 \r
 150 static void __exit rk_get_board_exit(void)\r
 151 {\r
 152         platform_driver_unregister(&rk_board_id_driver);\r
 153 }\r
 154 \r
 155 arch_initcall_sync(rk_get_board_init);\r
 156 module_exit(rk_get_board_exit);\r
 157 \r
 158 MODULE_AUTHOR("ROCKCHIP Corporation:lw@rock-chips.com");\r
 159 MODULE_DESCRIPTION("Interface for get board id");\r
 160 MODULE_LICENSE("GPL");\r