serial seems to work, but produces no output on headphone jack

[ms2-kexec] / hs_cons.c

/*
 * Provide kernel console on headphone jack
 *
 * Copyright (C) 2011 Michael Gernoth <michael@gernoth.net>
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License. See the file "COPYING" in the main directory of this archive
 * for more details.
 */

#include <linux/module.h>
#include <linux/gpio_mapping.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/serial_reg.h>
#include <linux/clk.h>

#include <plat/board.h>
#include <plat/control.h>
#include <asm/mach/serial_omap.h>

#include "prm.h"
#include "prm-regbits-34xx.h"

static int hs_switch = -1;

/*
 * int add_preferred_console(char *name, int idx, char *options)
 * c0069208 T add_preferred_console
 */

static int (*add_preferred_console)(char *, int, char*) = (int (*)(char*, int, char*))0xc0069208;

void my_omap_serial_init(int wake_gpio_strobe, unsigned int wake_strobe_enable_mask);
int my_omap_hs_init(void);
int my_serial_omap_init(void);

#define MAPPHONE_BPWAKE_STROBE_GPIO	157

static int __init headphone_cons_init(void)
{
	/* Get the headset switch gpio number from devtree */
	hs_switch = get_gpio_by_name("headset_uart_switch");
	if (hs_switch < 0)
		return -EINVAL;

	printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));

	if (!gpio_get_value(hs_switch))
		return -ENODEV;

	printk(KERN_INFO "Loading slightly modified omap serial driver...\n");
	my_serial_omap_init();

	printk(KERN_INFO "Enabling UART3...\n");
	my_omap_serial_init(MAPPHONE_BPWAKE_STROBE_GPIO, 0x01);
	my_omap_hs_init();

	/* route kernel uart out headset jack */
	gpio_direction_output(hs_switch, 0);
	printk(KERN_INFO "headset_uart_switch: %d, value: %d\n", hs_switch, gpio_get_value(hs_switch));

	//add_preferred_console("ttyS", 2, "115200");
	return 0;
}

#if 0
static void __exit headphone_cons_exit(void)
{
	if (hs_switch < 0)
		return;

	printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
	gpio_direction_output(hs_switch, 1);
	printk(KERN_INFO "value: %d\n", gpio_get_value(hs_switch));
}
#endif


module_init(headphone_cons_init);
#if 0
module_exit(headphone_cons_exit);
#endif

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Michael Gernoth <michael@gernoth.net>");