Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / staging / speakup / devsynth.c

diff --git a/kernel/drivers/staging/speakup/devsynth.c b/kernel/drivers/staging/speakup/devsynth.c
new file mode 100644 (file)
index 0000000..71c728a
--- /dev/null
+++ b/kernel/drivers/staging/speakup/devsynth.c
@@ -0,0 +1,95 @@
+#include <linux/errno.h>
+#include <linux/miscdevice.h>  /* for misc_register, and SYNTH_MINOR */
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#include "speakup.h"
+#include "spk_priv.h"
+
+#ifndef SYNTH_MINOR
+#define SYNTH_MINOR 25
+#endif
+
+static int misc_registered;
+static int dev_opened;
+
+static ssize_t speakup_file_write(struct file *fp, const char __user *buffer,
+                                 size_t nbytes, loff_t *ppos)
+{
+       size_t count = nbytes;
+       const char __user *ptr = buffer;
+       size_t bytes;
+       unsigned long flags;
+       u_char buf[256];
+
+       if (synth == NULL)
+               return -ENODEV;
+       while (count > 0) {
+               bytes = min(count, sizeof(buf));
+               if (copy_from_user(buf, ptr, bytes))
+                       return -EFAULT;
+               count -= bytes;
+               ptr += bytes;
+               spin_lock_irqsave(&speakup_info.spinlock, flags);
+               synth_write(buf, bytes);
+               spin_unlock_irqrestore(&speakup_info.spinlock, flags);
+       }
+       return (ssize_t) nbytes;
+}
+
+static ssize_t speakup_file_read(struct file *fp, char __user *buf,
+                                size_t nbytes, loff_t *ppos)
+{
+       return 0;
+}
+
+static int speakup_file_open(struct inode *ip, struct file *fp)
+{
+       if (synth == NULL)
+               return -ENODEV;
+       if (xchg(&dev_opened, 1))
+               return -EBUSY;
+       return 0;
+}
+
+static int speakup_file_release(struct inode *ip, struct file *fp)
+{
+       dev_opened = 0;
+       return 0;
+}
+
+static const struct file_operations synth_fops = {
+       .read = speakup_file_read,
+       .write = speakup_file_write,
+       .open = speakup_file_open,
+       .release = speakup_file_release,
+};
+
+static struct miscdevice synth_device = {
+       .minor = SYNTH_MINOR,
+       .name = "synth",
+       .fops = &synth_fops,
+};
+
+void speakup_register_devsynth(void)
+{
+       if (misc_registered != 0)
+               return;
+/* zero it so if register fails, deregister will not ref invalid ptrs */
+       if (misc_register(&synth_device))
+               pr_warn("Couldn't initialize miscdevice /dev/synth.\n");
+       else {
+               pr_info("initialized device: /dev/synth, node (MAJOR %d, MINOR %d)\n",
+                       MISC_MAJOR, SYNTH_MINOR);
+               misc_registered = 1;
+       }
+}
+
+void speakup_unregister_devsynth(void)
+{
+       if (!misc_registered)
+               return;
+       pr_info("speakup: unregistering synth device /dev/synth\n");
+       misc_deregister(&synth_device);
+       misc_registered = 0;
+}