git.zerfleddert.de Git - ms2-kexec/blob - headphone_cons.c

   1 /*
   2  * Provide kernel console on headphone jack
   3  */
   4
   5 #include <linux/module.h>
   6 #include <linux/gpio_mapping.h>
   7 #include <linux/gpio.h>
   8
   9 /*
  10  * int add_preferred_console(char *name, int idx, char *options)
  11  * c0069208 T add_preferred_console
  12  */
  13
  14 static int (*add_preferred_console)(char *, int, char*) = (int (*)(char*, int, char*))0xc0069208;
  15
  16 static int __init headphone_cons_init(void)
  17 {
  18         int hs_switch;
  19
  20         /* Get the headset switch gpio number from devtree */
  21         hs_switch = get_gpio_by_name("headset_uart_switch");
  22         if (hs_switch < 0)
  23                 return -EINVAL;
  24
  25         /* configure headset switch gpio as output and
  26            direction based on devtree setting */
  27         gpio_request(hs_switch, "mapphone audio headset uart switch");
  28
  29         /* route kernel uart out headset jack */
  30         gpio_direction_output(hs_switch, 0);
  31
  32         add_preferred_console("ttyS", 1, "115200");
  33         return 0;
  34 }
  35
  36 module_init(headphone_cons_init);
  37
  38 MODULE_LICENSE("GPL");
  39 MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");