+/* Copyright (c) 2016, 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.
+ */
+
+#include <linux/fs.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/wait.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/serial.h>
+#include <asm/uaccess.h>
+#include <linux/seq_file.h>
+#include <linux/module.h>
+#include <linux/slab.h>
+#include <linux/errno.h>
+#include <linux/delay.h>
+#include <linux/debugfs.h>
+#include <linux/device.h>
+#include <uapi/linux/gps_proxy.h>
+
+/* Module information */
+MODULE_DESCRIPTION( DRIVER_DESC );
+MODULE_LICENSE("GPL v2");
+
+#define LOC_SERVICE_SVC_ID 0x00000010
+#define LOC_SERVICE_V1 2
+#define LOC_SERVICE_INS_ID 0
+
+#define DRIVER_VERSION "v1.0"
+#define DRIVER_DESC "GPS TTY driver"
+#define MODULE_NAME "gps_proxy"
+#define TTY_DRIVER_NAME "gps_serial"
+#define TTY_DEV_NAME "ttyGPS"
+#define MAX_TTY_BUFFER_SZ 0x10000
+#define GPS_TTY_MAJOR 100 /* experimental range */
+#define DEVICE_NAME "gps_proxy_ch"
+#define CLASS_NAME "gps_proxy_class"
+
+static struct tty_driver *gps_proxy_tty_driver;
+static struct tty_port gps_proxy_tty_port;
+static bool g_port_open = false;
+static struct semaphore g_port_sem;
+static int gps_proxy_ch_driver_major = 0;
+static struct class* gps_proxy_ch_class = 0;
+static struct device* gps_proxy_ch_dev = 0;
+
+static void serial_port_shutdown(struct tty_port *tport)
+{
+}
+
+static int serial_port_activate(struct tty_port *tport, struct tty_struct *tty)
+{
+ return 0;
+}
+
+static struct tty_port_operations serial_port_ops = {
+ .activate = serial_port_activate,
+ .shutdown = serial_port_shutdown
+};
+
+static int gps_proxy_open(struct tty_struct *tty, struct file *file)
+{
+ int rc;
+ rc = tty_port_open(&gps_proxy_tty_port, tty, file);
+ g_port_open = true;
+ up(&g_port_sem);
+ return rc;
+}
+
+static void gps_proxy_close(struct tty_struct *tty, struct file *file)
+{
+ tty_port_close(tty->port, tty, file);
+ g_port_open = false;
+ down(&g_port_sem);
+}
+
+static void gps_proxy_tty_hangup(struct tty_struct *tty)
+{
+ tty_port_hangup(tty->port);
+}
+
+static int gps_proxy_write(struct tty_struct *tty,
+ const unsigned char *buffer, int count)
+{
+ return count;
+}
+
+static int gps_proxy_write_room(struct tty_struct *tty)
+{
+ return MAX_TTY_BUFFER_SZ;
+}
+
+static int gps_proxy_tty_chars_in_buffer(struct tty_struct *tty)
+{
+ return 0;
+}
+
+
+static int gps_proxy_tiocmget(struct tty_struct *tty)
+{
+ return 0;
+}
+
+static int gps_proxy_tiocmset(struct tty_struct *tty,
+ unsigned int set, unsigned int clear)
+{
+ return 0;
+}
+
+static int gps_proxy_ioctl(struct tty_struct *tty,
+ unsigned int cmd, unsigned long arg)
+{
+ return 0;
+}
+
+static struct tty_operations serial_ops = {
+ .open = gps_proxy_open,
+ .close = gps_proxy_close,
+ .hangup = gps_proxy_tty_hangup,
+ .write = gps_proxy_write,
+ .write_room = gps_proxy_write_room,
+ .chars_in_buffer = gps_proxy_tty_chars_in_buffer,
+ .tiocmget = gps_proxy_tiocmget,
+ .tiocmset = gps_proxy_tiocmset,
+ .ioctl = gps_proxy_ioctl,
+};
+
+int gps_proxy_ch_driver_open(struct inode *inode, struct file *filp)
+{
+ return 0;
+}
+
+int gps_proxy_ch_driver_close(struct inode *inode, struct file *filp)
+{
+ return 0;
+}
+
+long gps_proxy_chdev_ioctl(struct file *filp, unsigned int opt, unsigned long arg)
+{
+ int rc = 0;
+ struct gps_proxy_data buff;
+ switch (opt)
+ {
+ case QGPS_REGISTER_HANDLE:
+ /* DOWN is necessary to make client wait till port is open */
+ down(&g_port_sem);
+ /* UP to semaphore is necessary here for close or
+ next register handle (for parity) */
+ up(&g_port_sem);
+ rc = 0;
+ break;
+ case QGPS_SEND_NMEA:
+ pr_debug(KERN_INFO "Received string: %s\n",
+ ((struct gps_proxy_data*)arg)->nmea_string);
+ rc = access_ok(struct gps_proxy_data, (struct gps_proxy_data*)arg,
+ sizeof(struct gps_proxy_data));
+ if (!rc) {
+ pr_err(KERN_ERR "Invalid argument was received\n");
+ return rc;
+ }
+ rc = copy_from_user((void*)&buff, (void*)arg, sizeof(buff));
+ if (rc) {
+ pr_err(KERN_ERR "Number of bytes that \
+ couldn't be copied: %d", rc);
+ return -EFAULT;
+ }
+ if (buff.nmea_length < QMI_LOC_NMEA_STRING_MAX_LENGTH_V02 + 1) {
+ pr_debug(KERN_INFO "Received string: %s\n",
+ buff.nmea_string);
+ rc = tty_insert_flip_string(&gps_proxy_tty_port,
+ buff.nmea_string,
+ strnlen(buff.nmea_string,
+ QMI_LOC_NMEA_STRING_MAX_LENGTH_V02) + 1);
+ if (rc < 0) {
+ pr_err(KERN_ERR "Error flipping string");
+ return rc;
+ }
+ tty_flip_buffer_push(&gps_proxy_tty_port);
+ }
+ else {
+ pr_err(KERN_ERR "Illegal message size");
+ rc = -EFAULT;
+ }
+ break;
+ case QGPS_IS_ACTIVE:
+ if (g_port_open)
+ rc = 0;
+ else
+ rc = -EFAULT;
+ break;
+ default:
+ rc = -EFAULT;
+ break;
+ }
+ return rc;
+}
+
+struct file_operations gps_proxy_ch_driver_ops = {
+ open: gps_proxy_ch_driver_open,
+ unlocked_ioctl: gps_proxy_chdev_ioctl,
+ release: gps_proxy_ch_driver_close
+};
+
+static int __init gps_proxy_init(void)
+{
+ int rc;
+ struct device *ttydev;
+
+ sema_init(&g_port_sem,0);
+
+ gps_proxy_ch_driver_major = register_chrdev(0, "gps_proxy_ch_dev",
+ &gps_proxy_ch_driver_ops);
+ if (gps_proxy_ch_driver_major < 0) {
+ pr_err(KERN_ERR "Failed to register char device\n");
+ return -EFAULT;
+ }
+ else {
+ pr_debug(KERN_INFO "char device registered with major %d\n",
+ gps_proxy_ch_driver_major);
+ }
+
+ /* Register the device class */
+ gps_proxy_ch_class = class_create(THIS_MODULE, CLASS_NAME);
+ if (IS_ERR(gps_proxy_ch_class)){
+ unregister_chrdev(gps_proxy_ch_driver_major, DEVICE_NAME);
+ pr_debug(KERN_ALERT "Failed to register device class\n");
+ return -EFAULT;
+ }
+ pr_debug(KERN_INFO "EBBChar: device class registered correctly\n");
+
+ /* Register the device driver */
+ gps_proxy_ch_dev = device_create(gps_proxy_ch_class, NULL,
+ MKDEV(gps_proxy_ch_driver_major, 0), NULL, DEVICE_NAME);
+ if (IS_ERR(gps_proxy_ch_dev)){
+ class_destroy(gps_proxy_ch_class);
+ unregister_chrdev(gps_proxy_ch_driver_major, DEVICE_NAME);
+ pr_debug(KERN_ALERT "Failed to create the device\n");
+ return -EFAULT;
+ }
+
+ /* allocate the tty driver */
+ gps_proxy_tty_driver = alloc_tty_driver(1);
+ if (!gps_proxy_tty_driver)
+ return -ENOMEM;
+
+ tty_port_init(&gps_proxy_tty_port);
+ gps_proxy_tty_port.ops = &serial_port_ops;
+
+ /* initialize the tty driver */
+ gps_proxy_tty_driver->driver_name = TTY_DRIVER_NAME;
+ gps_proxy_tty_driver->name = TTY_DEV_NAME;
+ gps_proxy_tty_driver->major = GPS_TTY_MAJOR;
+ gps_proxy_tty_driver->minor_start = 0;
+ gps_proxy_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
+ gps_proxy_tty_driver->subtype = SERIAL_TYPE_NORMAL;
+ gps_proxy_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
+ gps_proxy_tty_driver->init_termios = tty_std_termios;
+
+ tty_set_operations(gps_proxy_tty_driver, &serial_ops);
+
+ /* register the tty driver */
+ rc = tty_register_driver(gps_proxy_tty_driver);
+ if (rc) {
+ pr_err("Failed to register gps_proxy tty driver\n");
+ put_tty_driver(gps_proxy_tty_driver);
+ return rc;
+ }
+
+ ttydev = tty_port_register_device(&gps_proxy_tty_port, gps_proxy_tty_driver, 0, 0);
+ if (IS_ERR(ttydev)) {
+ rc = PTR_ERR(ttydev);
+ pr_err("Failed to register gps_proxy tty proxy\n");
+ return rc;
+ }
+
+ pr_debug(KERN_INFO DRIVER_DESC " \n" DRIVER_VERSION);
+ return rc;
+}
+
+static void __exit gps_proxy_exit(void)
+{
+ tty_unregister_device(gps_proxy_tty_driver, 0);
+ tty_unregister_driver(gps_proxy_tty_driver);
+ unregister_chrdev(gps_proxy_ch_driver_major, "gps_proxy_ch_dev");
+ device_destroy(gps_proxy_ch_class, MKDEV(gps_proxy_ch_driver_major, 0));
+ class_unregister(gps_proxy_ch_class);
+ class_destroy(gps_proxy_ch_class);
+}
+
+late_initcall(gps_proxy_init);
+module_exit(gps_proxy_exit);
projects / karo-tx-linux.git / commitdiff