From fd2d771d1ec124a89fa21e2a69b411020e21c6cd Mon Sep 17 00:00:00 2001
From: Robin Mallinson <robin.mallinson+rpi@gmail.com>
Date: Mon, 5 Nov 2012 22:23:45 +0000
Subject: [PATCH] Add dev_read() function to driver to allow it to report
 current settings for each of the 8 PWMs via /dev/servoblaster.

---
 ServoBlaster/servoblaster.c | 48 +++++++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

diff --git a/ServoBlaster/servoblaster.c b/ServoBlaster/servoblaster.c
index 4d59df5..609a4a2 100644
--- a/ServoBlaster/servoblaster.c
+++ b/ServoBlaster/servoblaster.c
@@ -323,7 +323,55 @@ static int dev_open(struct inode *inod,struct file *fil)
 
 static ssize_t dev_read(struct file *filp,char *buf,size_t count,loff_t *f_pos)
 {
+#if 0
+	int servo;
+	static int idx=0;
+	// Allow 10 chars per line:
+	static char returnedData[NUM_SERVOS * 10] = {0};
+
+	if (0 == *f_pos)
+	{
+		// Get fresh data
+		for (servo=0, idx=0; servo < NUM_SERVOS; ++servo)
+		{
+			if (wait_for_servo(servo))
+				return -EINTR;
+
+			idx += snprintf(returnedData+idx, sizeof(returnedData)-idx,
+				"%i %lu\n",
+				servo,
+				ctl->cb[servo*4+1].length / sizeof(uint32_t)
+			);
+		}
+	}
+
+	if (*f_pos >= idx)
+	{
+		//EOF
+		return 0;
+	}
+	else if ( (*f_pos + count) < idx )
+	{
+		// Sufficient data to fulfil request
+		if (copy_to_user(buf,returnedData+fpos,count) {
+			return -EFAULT;
+		}
+		*f_pos+=count;
+		return count;
+	}
+	else
+	{
+		// Return all the data we have
+		const int nBytes = idx-*f_pos;
+		if (copy_to_user(buf,returnedData+*f_pos, nBytes) {
+                        return -EFAULT;
+                }
+		*f_pos+=nBytes;
+		return nBytes;
+	}
+#else
 	return 0;
+#endif
 }
 
 static ssize_t dev_write(struct file *filp,const char *buf,size_t count,loff_t *f_pos)