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

   1 /*
   2  * Provide kernel console on headphone jack
   3  *
   4  * Copyright (C) 2011 Michael Gernoth <michael@gernoth.net>
   5  *
   6  * This file is subject to the terms and conditions of the GNU General Public
   7  * License. See the file "COPYING" in the main directory of this archive
   8  * for more details.
   9  */
  10
  11 #include <linux/module.h>
  12 #include <linux/gpio_mapping.h>
  13 #include <linux/gpio.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/serial_reg.h>
  16 #include <linux/clk.h>
  17
  18 #include <plat/board.h>
  19 #include <plat/control.h>
  20 #include <asm/mach/serial_omap.h>
  21
  22 #include "prm.h"
  23 #include "prm-regbits-34xx.h"
  24
  25 static int hs_switch = -1;
  26
  27 /*
  28  * int add_preferred_console(char *name, int idx, char *options)
  29  * c0069208 T add_preferred_console
  30  */
  31
  32 static int (*add_preferred_console)(char *, int, char*) = (int (*)(char*, int, char*))0xc0069208;
  33
  34 void my_omap_serial_init(int wake_gpio_strobe, unsigned int wake_strobe_enable_mask);
  35 int my_omap_hs_init(void);
  36 int my_serial_omap_init(void);
  37
  38 #define MAPPHONE_BPWAKE_STROBE_GPIO     157
  39
  40 static int __init headphone_cons_init(void)
  41 {
  42         /* Get the headset switch gpio number from devtree */
  43         hs_switch = get_gpio_by_name("headset_uart_switch");
  44         if (hs_switch < 0)
  45                 return -EINVAL;
  46
  47         printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));
  48
  49         if (!gpio_get_value(hs_switch))
  50                 return -ENODEV;
  51
  52         printk(KERN_INFO "Loading slightly modified omap serial driver...\n");
  53         my_serial_omap_init();
  54
  55         printk(KERN_INFO "Enabling UART3...\n");
  56         my_omap_serial_init(MAPPHONE_BPWAKE_STROBE_GPIO, 0x01);
  57         my_omap_hs_init();
  58
  59         /* route kernel uart out headset jack */
  60         gpio_direction_output(hs_switch, 0);
  61         printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));
  62
  63         //add_preferred_console("ttyS", 2, "115200");
  64         return 0;
  65 }
  66
  67 #if 0
  68 static void __exit headphone_cons_exit(void)
  69 {
  70         if (hs_switch < 0)
  71                 return;
  72
  73         printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
  74         gpio_direction_output(hs_switch, 1);
  75         printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
  76 }
  77 #endif
  78
  79
  80 module_init(headphone_cons_init);
  81 #if 0
  82 module_exit(headphone_cons_exit);
  83 #endif
  84
  85 MODULE_LICENSE("GPL");
  86 MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");