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 void activate_emu_uart(void);
  37
  38 #define MAPPHONE_BPWAKE_STROBE_GPIO     157
  39
  40 static int find_ms2_dev(struct device *dev, void *data)
  41 {
  42         if (!strncmp((char*)data, dev_name(dev), strlen((char*)data))) {
  43                 printk(KERN_INFO "Found it\n");
  44                 return 1;
  45         }
  46         return 0;
  47 }
  48
  49 static int __init headphone_cons_init(void)
  50 {
  51         int bpwake_strobe_gpio;
  52         struct device *uart3 = NULL;
  53
  54         /* Remove old uart3 device which was disabled... */
  55         printk(KERN_INFO "Searching for omap-uart.3...\n");
  56
  57         uart3 = device_find_child(&platform_bus, "omap-uart.3", find_ms2_dev);
  58         if (uart3 == NULL)
  59                 return-ENODEV;
  60
  61         printk(KERN_INFO "Deleting old device...\n");
  62         device_del(uart3);
  63
  64         /* Get the headset switch gpio number from devtree */
  65         hs_switch = get_gpio_by_name("headset_uart_switch");
  66         if (hs_switch < 0)
  67                 return -EINVAL;
  68
  69         printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));
  70
  71         if (!gpio_get_value(hs_switch))
  72                 return -ENODEV;
  73
  74         printk(KERN_INFO "Activating emu_uart on mini-usb port\n");
  75         activate_emu_uart();
  76
  77         printk(KERN_INFO "Enabling UART3...\n");
  78         bpwake_strobe_gpio = get_gpio_by_name("ipc_bpwake_strobe");
  79         if (bpwake_strobe_gpio < 0)
  80                 bpwake_strobe_gpio = MAPPHONE_BPWAKE_STROBE_GPIO;
  81         printk("Serial init with strobe pin %d\n", bpwake_strobe_gpio);
  82         my_omap_serial_init(bpwake_strobe_gpio, 0x01);
  83         my_omap_hs_init();
  84
  85         /* route kernel uart out headset jack */
  86         gpio_set_value(hs_switch, 0);
  87         printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));
  88
  89         add_preferred_console("ttyS", 2, "115200");
  90         return 0;
  91 }
  92
  93 #if 0
  94 static void __exit headphone_cons_exit(void)
  95 {
  96         if (hs_switch < 0)
  97                 return;
  98
  99         printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
 100         gpio_direction_output(hs_switch, 1);
 101         printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
 102 }
 103 #endif
 104
 105
 106 module_init(headphone_cons_init);
 107 #if 0
 108 module_exit(headphone_cons_exit);
 109 #endif
 110
 111 MODULE_LICENSE("GPL");
 112 MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");