Initial Contribution
msm-2.6.38: tag AU_LINUX_ANDROID_GINGERBREAD.02.03.04.00.142
Signed-off-by: Bryan Huntsman <bryanh@codeaurora.org>
diff --git a/arch/arm/mach-msm/smd_nmea.c b/arch/arm/mach-msm/smd_nmea.c
new file mode 100644
index 0000000..1aedbf5
--- /dev/null
+++ b/arch/arm/mach-msm/smd_nmea.c
@@ -0,0 +1,205 @@
+/* Copyright (c) 2008-2009, Code Aurora Forum. 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.
+ *
+ */
+/*
+ * SMD NMEA Driver -- Provides GPS NMEA device to SMD port interface.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/cdev.h>
+#include <linux/device.h>
+#include <linux/wait.h>
+#include <linux/sched.h>
+#include <linux/miscdevice.h>
+#include <linux/workqueue.h>
+#include <linux/uaccess.h>
+
+#include <mach/msm_smd.h>
+
+#define MAX_BUF_SIZE 200
+
+static DEFINE_MUTEX(nmea_ch_lock);
+static DEFINE_MUTEX(nmea_rx_buf_lock);
+
+static DECLARE_WAIT_QUEUE_HEAD(nmea_wait_queue);
+
+struct nmea_device_t {
+ struct miscdevice misc;
+
+ struct smd_channel *ch;
+
+ unsigned char rx_buf[MAX_BUF_SIZE];
+ unsigned int bytes_read;
+};
+
+struct nmea_device_t *nmea_devp;
+
+static void nmea_work_func(struct work_struct *ws)
+{
+ int sz;
+
+ for (;;) {
+ sz = smd_cur_packet_size(nmea_devp->ch);
+ if (sz == 0)
+ break;
+ if (sz > smd_read_avail(nmea_devp->ch))
+ break;
+ if (sz > MAX_BUF_SIZE) {
+ smd_read(nmea_devp->ch, 0, sz);
+ continue;
+ }
+
+ mutex_lock(&nmea_rx_buf_lock);
+ if (smd_read(nmea_devp->ch, nmea_devp->rx_buf, sz) != sz) {
+ mutex_unlock(&nmea_rx_buf_lock);
+ printk(KERN_ERR "nmea: not enough data?!\n");
+ continue;
+ }
+ nmea_devp->bytes_read = sz;
+ mutex_unlock(&nmea_rx_buf_lock);
+ wake_up_interruptible(&nmea_wait_queue);
+ }
+}
+
+struct workqueue_struct *nmea_wq;
+static DECLARE_WORK(nmea_work, nmea_work_func);
+
+static void nmea_notify(void *priv, unsigned event)
+{
+ switch (event) {
+ case SMD_EVENT_DATA: {
+ int sz;
+ sz = smd_cur_packet_size(nmea_devp->ch);
+ if ((sz > 0) && (sz <= smd_read_avail(nmea_devp->ch)))
+ queue_work(nmea_wq, &nmea_work);
+ break;
+ }
+ case SMD_EVENT_OPEN:
+ printk(KERN_INFO "nmea: smd opened\n");
+ break;
+ case SMD_EVENT_CLOSE:
+ printk(KERN_INFO "nmea: smd closed\n");
+ break;
+ }
+}
+
+static ssize_t nmea_read(struct file *fp, char __user *buf,
+ size_t count, loff_t *pos)
+{
+ int r;
+ int bytes_read;
+
+ r = wait_event_interruptible(nmea_wait_queue,
+ nmea_devp->bytes_read);
+ if (r < 0) {
+ /* qualify error message */
+ if (r != -ERESTARTSYS) {
+ /* we get this anytime a signal comes in */
+ printk(KERN_ERR "ERROR:%s:%i:%s: "
+ "wait_event_interruptible ret %i\n",
+ __FILE__,
+ __LINE__,
+ __func__,
+ r
+ );
+ }
+ return r;
+ }
+
+ mutex_lock(&nmea_rx_buf_lock);
+ bytes_read = nmea_devp->bytes_read;
+ nmea_devp->bytes_read = 0;
+ r = copy_to_user(buf, nmea_devp->rx_buf, bytes_read);
+ mutex_unlock(&nmea_rx_buf_lock);
+
+ if (r > 0) {
+ printk(KERN_ERR "ERROR:%s:%i:%s: "
+ "copy_to_user could not copy %i bytes.\n",
+ __FILE__,
+ __LINE__,
+ __func__,
+ r);
+ return r;
+ }
+
+ return bytes_read;
+}
+
+static int nmea_open(struct inode *ip, struct file *fp)
+{
+ int r = 0;
+
+ mutex_lock(&nmea_ch_lock);
+ if (nmea_devp->ch == 0)
+ r = smd_open("GPSNMEA", &nmea_devp->ch, nmea_devp, nmea_notify);
+ mutex_unlock(&nmea_ch_lock);
+
+ return r;
+}
+
+static int nmea_release(struct inode *ip, struct file *fp)
+{
+ int r = 0;
+
+ mutex_lock(&nmea_ch_lock);
+ if (nmea_devp->ch != 0) {
+ r = smd_close(nmea_devp->ch);
+ nmea_devp->ch = 0;
+ }
+ mutex_unlock(&nmea_ch_lock);
+
+ return r;
+}
+
+static const struct file_operations nmea_fops = {
+ .owner = THIS_MODULE,
+ .read = nmea_read,
+ .open = nmea_open,
+ .release = nmea_release,
+};
+
+static struct nmea_device_t nmea_device = {
+ .misc = {
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "nmea",
+ .fops = &nmea_fops,
+ }
+};
+
+static void __exit nmea_exit(void)
+{
+ destroy_workqueue(nmea_wq);
+ misc_deregister(&nmea_device.misc);
+}
+
+static int __init nmea_init(void)
+{
+ int ret;
+
+ nmea_device.bytes_read = 0;
+ nmea_devp = &nmea_device;
+
+ nmea_wq = create_singlethread_workqueue("nmea");
+ if (nmea_wq == 0)
+ return -ENOMEM;
+
+ ret = misc_register(&nmea_device.misc);
+ return ret;
+}
+
+module_init(nmea_init);
+module_exit(nmea_exit);
+
+MODULE_DESCRIPTION("MSM Shared Memory NMEA Driver");
+MODULE_LICENSE("GPL v2");