[PATCH] chardev: GPIO for SCx200 & PC-8736x: migrate file-ops to common module

Now that the read(), write() file-ops are dispatching gpio-ops via the vtable,
they are generic, and can be moved 'verbatim' to the nsc_gpio common-support
module.  After the move, various symbols are renamed to update 'scx200_' to
'nsc_', and headers are adjusted accordingly.
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

drivers/char/nsc_gpio.c

@@ -19,9 +19,89 @@
 
 #define NAME "nsc_gpio"
 
-MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>");
-MODULE_DESCRIPTION("NatSemi GPIO Common Methods");
-MODULE_LICENSE("GPL");
+ssize_t nsc_gpio_write(struct file *file, const char __user *data,
+		       size_t len, loff_t *ppos)
+{
+	unsigned m = iminor(file->f_dentry->d_inode);
+	struct nsc_gpio_ops *amp = file->private_data;
+	size_t i;
+	int err = 0;
+
+	for (i = 0; i < len; ++i) {
+		char c;
+		if (get_user(c, data + i))
+			return -EFAULT;
+		switch (c) {
+		case '0':
+			amp->gpio_set(m, 0);
+			break;
+		case '1':
+			amp->gpio_set(m, 1);
+			break;
+		case 'O':
+			printk(KERN_INFO NAME ": GPIO%d output enabled\n", m);
+			amp->gpio_config(m, ~1, 1);
+			break;
+		case 'o':
+			printk(KERN_INFO NAME ": GPIO%d output disabled\n", m);
+			amp->gpio_config(m, ~1, 0);
+			break;
+		case 'T':
+			printk(KERN_INFO NAME ": GPIO%d output is push pull\n",
+			       m);
+			amp->gpio_config(m, ~2, 2);
+			break;
+		case 't':
+			printk(KERN_INFO NAME ": GPIO%d output is open drain\n",
+			       m);
+			amp->gpio_config(m, ~2, 0);
+			break;
+		case 'P':
+			printk(KERN_INFO NAME ": GPIO%d pull up enabled\n", m);
+			amp->gpio_config(m, ~4, 4);
+			break;
+		case 'p':
+			printk(KERN_INFO NAME ": GPIO%d pull up disabled\n", m);
+			amp->gpio_config(m, ~4, 0);
+			break;
+
+		case 'v':
+			/* View Current pin settings */
+			amp->gpio_dump(m);
+			break;
+		case '\n':
+			/* end of settings string, do nothing */
+			break;
+		default:
+			printk(KERN_ERR NAME
+			       ": GPIO-%2d bad setting: chr<0x%2x>\n", m,
+			       (int)c);
+			err++;
+		}
+	}
+	if (err)
+		return -EINVAL;	/* full string handled, report error */
+
+	return len;
+}
+
+ssize_t nsc_gpio_read(struct file *file, char __user * buf,
+		      size_t len, loff_t * ppos)
+{
+	unsigned m = iminor(file->f_dentry->d_inode);
+	int value;
+	struct nsc_gpio_ops *amp = file->private_data;
+
+	value = amp->gpio_get(m);
+	if (put_user(value ? '1' : '0', buf))
+		return -EFAULT;
+
+	return 1;
+}
+
+/* common routines for both scx200_gpio and pc87360_gpio */
+EXPORT_SYMBOL(nsc_gpio_write);
+EXPORT_SYMBOL(nsc_gpio_read);
 
 static int __init nsc_gpio_init(void)
 {
@@ -34,12 +114,9 @@ static void __exit nsc_gpio_cleanup(void)
 	printk(KERN_DEBUG NAME " cleanup\n");
 }
 
-/* prepare for
-   common routines for both scx200_gpio and pc87360_gpio
-EXPORT_SYMBOL(scx200_gpio_write);
-EXPORT_SYMBOL(scx200_gpio_read);
-EXPORT_SYMBOL(scx200_gpio_release);
-*/
-
 module_init(nsc_gpio_init);
 module_exit(nsc_gpio_cleanup);
+
+MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>");
+MODULE_DESCRIPTION("NatSemi GPIO Common Methods");
+MODULE_LICENSE("GPL");

drivers/char/scx200_gpio.c

@@ -37,6 +37,12 @@ MODULE_PARM_DESC(major, "Major device number");
 
 extern void scx200_gpio_dump(unsigned index);
 
+extern ssize_t nsc_gpio_write(struct file *file, const char __user *data,
+			      size_t len, loff_t *ppos);
+
+extern ssize_t nsc_gpio_read(struct file *file, char __user *buf,
+			     size_t len, loff_t *ppos);
+
 struct nsc_gpio_ops scx200_access = {
 	.owner		= THIS_MODULE,
 	.gpio_config	= scx200_gpio_configure,
@@ -49,84 +55,6 @@ struct nsc_gpio_ops scx200_access = {
 	.gpio_current	= scx200_gpio_current
 };
 
-static ssize_t scx200_gpio_write(struct file *file, const char __user *data,
-				 size_t len, loff_t *ppos)
-{
-	unsigned m = iminor(file->f_dentry->d_inode);
-	struct nsc_gpio_ops *amp = file->private_data;
-	size_t i;
-	int err = 0;
-
-	for (i = 0; i < len; ++i) {
-		char c;
-		if (get_user(c, data + i))
-			return -EFAULT;
-		switch (c) {
-		case '0':
-			amp->gpio_set(m, 0);
-			break;
-		case '1':
-			amp->gpio_set(m, 1);
-			break;
-		case 'O':
-			printk(KERN_INFO NAME ": GPIO%d output enabled\n", m);
-			amp->gpio_config(m, ~1, 1);
-			break;
-		case 'o':
-			printk(KERN_INFO NAME ": GPIO%d output disabled\n", m);
-			amp->gpio_config(m, ~1, 0);
-			break;
-		case 'T':
-			printk(KERN_INFO NAME ": GPIO%d output is push pull\n", m);
-			amp->gpio_config(m, ~2, 2);
-			break;
-		case 't':
-			printk(KERN_INFO NAME ": GPIO%d output is open drain\n", m);
-			amp->gpio_config(m, ~2, 0);
-			break;
-		case 'P':
-			printk(KERN_INFO NAME ": GPIO%d pull up enabled\n", m);
-			amp->gpio_config(m, ~4, 4);
-			break;
-		case 'p':
-			printk(KERN_INFO NAME ": GPIO%d pull up disabled\n", m);
-			amp->gpio_config(m, ~4, 0);
-			break;
-
-		case 'v':
-			/* View Current pin settings */
-			amp->gpio_dump(m);
-			break;
-		case '\n':
-			/* end of settings string, do nothing */
-			break;
-		default:
-			printk(KERN_ERR NAME
-			       ": GPIO-%2d bad setting: chr<0x%2x>\n", m,
-			       (int)c);
-			err++;
-		}
-	}
-	if (err)
-		return -EINVAL;	/* full string handled, report error */
-
-	return len;
-}
-
-static ssize_t scx200_gpio_read(struct file *file, char __user *buf,
-				size_t len, loff_t *ppos)
-{
-	unsigned m = iminor(file->f_dentry->d_inode);
-	int value;
-	struct nsc_gpio_ops *amp = file->private_data;
-
-	value = amp->gpio_get(m);
-	if (put_user(value ? '1' : '0', buf))
-		return -EFAULT;
-
-	return 1;
-}
-
 static int scx200_gpio_open(struct inode *inode, struct file *file)
 {
 	unsigned m = iminor(inode);
@@ -145,8 +73,8 @@ static int scx200_gpio_release(struct inode *inode, struct file *file)
 
 static struct file_operations scx200_gpio_fops = {
 	.owner   = THIS_MODULE,
-	.write   = scx200_gpio_write,
-	.read    = scx200_gpio_read,
+	.write   = nsc_gpio_write,
+	.read    = nsc_gpio_read,
 	.open    = scx200_gpio_open,
 	.release = scx200_gpio_release,
 };

include/linux/nsc_gpio.h

@@ -31,3 +31,8 @@ struct nsc_gpio_ops {
 	int	(*gpio_current)	(unsigned iminor);
 };
 
+extern ssize_t nsc_gpio_write(struct file *file, const char __user *data,
+			      size_t len, loff_t *ppos);
+
+extern ssize_t nsc_gpio_read(struct file *file, char __user *buf,
+			     size_t len, loff_t *ppos);