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 void activate_emu_uart(void);
  38
  39 #define MAPPHONE_BPWAKE_STROBE_GPIO     157
  40
  41 static int __init headphone_cons_init(void)
  42 {
  43         /* Get the headset switch gpio number from devtree */
  44         hs_switch = get_gpio_by_name("headset_uart_switch");
  45         if (hs_switch < 0)
  46                 return -EINVAL;
  47
  48         printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));
  49
  50         if (!gpio_get_value(hs_switch))
  51                 return -ENODEV;
  52
  53         printk(KERN_INFO "Loading slightly modified omap serial driver...\n");
  54         my_serial_omap_init();
  55
  56         printk(KERN_INFO "Enabling UART3...\n");
  57         my_omap_serial_init(MAPPHONE_BPWAKE_STROBE_GPIO, 0x01);
  58         my_omap_hs_init();
  59
  60         /* route kernel uart out headset jack */
  61         gpio_set_value(hs_switch, 0);
  62         printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));
  63
  64         activate_emu_uart();
  65
  66         //add_preferred_console("ttyS", 2, "115200");
  67         return 0;
  68 }
  69
  70 #if 0
  71 static void __exit headphone_cons_exit(void)
  72 {
  73         if (hs_switch < 0)
  74                 return;
  75
  76         printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
  77         gpio_direction_output(hs_switch, 1);
  78         printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
  79 }
  80 #endif
  81
  82
  83 module_init(headphone_cons_init);
  84 #if 0
  85 module_exit(headphone_cons_exit);
  86 #endif
  87
  88 MODULE_LICENSE("GPL");
  89 MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");