arch/arm/mach-msm/reset_modem.c

/* Copyright (c) 2008-2009, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */
/*
 * MSM architecture driver to reset the modem
 */
#include <linux/uaccess.h>
#include <linux/module.h>
#include <linux/fs.h>
#include <linux/miscdevice.h>
#include <mach/proc_comm.h>

#include "smd_private.h"

#define DEBUG
/* #undef DEBUG */
#ifdef DEBUG
#define D(x...) printk(x)
#else
#define D(x...) do {} while (0)
#endif

static ssize_t reset_modem_read(struct file *fp, char __user *buf,
			size_t count, loff_t *pos)
{
	return 0;
}

static ssize_t reset_modem_write(struct file *fp, const char __user *buf,
			 size_t count, loff_t *pos)
{
	unsigned char cmd[64];
	int len;
	int time;
	int zero = 0;
	int r;

	if (count < 1)
		return 0;

	len = count > 63 ? 63 : count;

	if (copy_from_user(cmd, buf, len))
		return -EFAULT;

	cmd[len] = 0;

	/* lazy */
	if (cmd[len-1] == '\n') {
		cmd[len-1] = 0;
		len--;
	}

	if (!strncmp(cmd, "wait", 4)) {
		D(KERN_ERR "INFO:%s:%i:%s: "
		       "MODEM RESTART: WAIT\n",
		       __FILE__,
		       __LINE__,
		       __func__);
		smsm_reset_modem(SMSM_MODEM_WAIT);
	} else if (!strncmp(cmd, "continue", 8)) {
		D(KERN_ERR "INFO:%s:%i:%s: "
		       "MODEM RESTART: CONTINUE\n",
		       __FILE__,
		       __LINE__,
		       __func__);
		smsm_reset_modem_cont();
	} else if (!strncmp(cmd, "download", 8)) {
		D(KERN_ERR "INFO:%s:%i:%s: "
		       "MODEM RESTART: DOWNLOAD\n",
		       __FILE__,
		       __LINE__,
		       __func__);
		smsm_reset_modem(SMSM_SYSTEM_DOWNLOAD);
	} else if (sscanf(cmd, "deferred reset %i", &time) == 1) {
		D(KERN_ERR "INFO:%s:%i:%s: "
		       "MODEM RESTART: DEFERRED RESET %ims\n",
		       __FILE__,
		       __LINE__,
		       __func__,
		       time);
		if (time == 0) {
			r = 0;
			msm_proc_comm_reset_modem_now();
		} else {
			r = msm_proc_comm(PCOM_RESET_MODEM, &time, &zero);
		}
		if (r < 0)
			return r;
	} else if (!strncmp(cmd, "deferred reset", 14)) {
		D(KERN_ERR "INFO:%s:%i:%s: "
		       "MODEM RESTART: DEFERRED RESET 0ms\n",
		       __FILE__,
		       __LINE__,
		       __func__);
		r = 0;
		msm_proc_comm_reset_modem_now();
		if (r < 0)
			return r;
	} else if (!strncmp(cmd, "reset chip now", 14)) {
		uint param1 = 0x0;
		uint param2 = 0x0;

		D(KERN_ERR "INFO:%s:%i:%s: "
		  "MODEM RESTART: CHIP RESET IMMEDIATE\n",
		  __FILE__,
		  __LINE__,
		  __func__);

		r = msm_proc_comm(PCOM_RESET_CHIP_IMM, &param1, &param2);

		if (r < 0)
			return r;
	} else if (!strncmp(cmd, "reset chip", 10)) {

		uint param1 = 0x0;
		uint param2 = 0x0;

		D(KERN_ERR "INFO:%s:%i:%s: "
		  "MODEM RESTART: CHIP RESET \n",
		  __FILE__,
		  __LINE__,
		  __func__);

		r = msm_proc_comm(PCOM_RESET_CHIP, &param1, &param2);

		if (r < 0)
			return r;
	} else if (!strncmp(cmd, "reset", 5)) {
		printk(KERN_ERR "INFO:%s:%i:%s: "
		       "MODEM RESTART: RESET\n",
		       __FILE__,
		       __LINE__,
		       __func__);
		smsm_reset_modem(SMSM_RESET);
	} else
		return -EINVAL;

	return count;
}

static int reset_modem_open(struct inode *ip, struct file *fp)
{
	return 0;
}

static int reset_modem_release(struct inode *ip, struct file *fp)
{
	return 0;
}

static const struct file_operations reset_modem_fops = {
	.owner = THIS_MODULE,
	.read = reset_modem_read,
	.write = reset_modem_write,
	.open = reset_modem_open,
	.release = reset_modem_release,
};

static struct miscdevice reset_modem_dev = {
	.minor = MISC_DYNAMIC_MINOR,
	.name = "reset_modem",
	.fops = &reset_modem_fops,
};

static int __init reset_modem_init(void)
{
	return misc_register(&reset_modem_dev);
}

module_init(reset_modem_init);

MODULE_DESCRIPTION("Reset Modem");
MODULE_LICENSE("GPL v2");