seq_file: Introduce DEFINE_SHOW_ATTRIBUTE() helper macro

The DEFINE_SHOW_ATTRIBUTE() helper macro would be useful for current
users, which are many of them, and for new comers to decrease code
duplication.

Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Darren Hart (VMware) <dvhart@infradead.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>

drivers/mfd/ab8500-debugfs.c

@@ -1258,20 +1258,6 @@ static struct ab8500_prcmu_ranges ab8540_debug_ranges[AB8500_NUM_BANKS] = {
 	},
 };
 
-#define DEFINE_SHOW_ATTRIBUTE(__name)					      \
-static int __name ## _open(struct inode *inode, struct file *file)	      \
-{									      \
-	return single_open(file, __name ## _show, inode->i_private);	      \
-}									      \
-									      \
-static const struct file_operations __name ## _fops = {			      \
-	.owner		= THIS_MODULE,					      \
-	.open		= __name ## _open,				      \
-	.read		= seq_read,					      \
-	.llseek		= seq_lseek,					      \
-	.release	= single_release,				      \
-}									      \
-
 static irqreturn_t ab8500_debug_handler(int irq, void *data)
 {
 	char buf[16];

drivers/platform/x86/pmc_atom.c

@@ -208,20 +208,6 @@ static const struct pmc_data cht_data = {
 	.clks = cht_clks,
 };
 
-#define DEFINE_SHOW_ATTRIBUTE(__name)					\
-static int __name ## _open(struct inode *inode, struct file *file)	\
-{									\
-	return single_open(file, __name ## _show, inode->i_private);	\
-}									\
-									\
-static const struct file_operations __name ## _fops = {			\
-	.owner		= THIS_MODULE,					\
-	.open		= __name ## _open,				\
-	.read		= seq_read,					\
-	.llseek		= seq_lseek,					\
-	.release	= single_release,				\
-}
-
 static inline u32 pmc_reg_read(struct pmc_dev *pmc, int reg_offset)
 {
 	return readl(pmc->regmap + reg_offset);

include/linux/seq_file.h

@@ -140,6 +140,20 @@ void *__seq_open_private(struct file *, const struct seq_operations *, int);
 int seq_open_private(struct file *, const struct seq_operations *, int);
 int seq_release_private(struct inode *, struct file *);
 
+#define DEFINE_SHOW_ATTRIBUTE(__name)					\
+static int __name ## _open(struct inode *inode, struct file *file)	\
+{									\
+	return single_open(file, __name ## _show, inode->i_private);	\
+}									\
+									\
+static const struct file_operations __name ## _fops = {			\
+	.owner		= THIS_MODULE,					\
+	.open		= __name ## _open,				\
+	.read		= seq_read,					\
+	.llseek		= seq_lseek,					\
+	.release	= single_release,				\
+}
+
 static inline struct user_namespace *seq_user_ns(struct seq_file *seq)
 {
 #ifdef CONFIG_USER_NS

net/bluetooth/hci_debugfs.c

@@ -90,19 +90,6 @@ static int __name ## _show(struct seq_file *f, void *ptr)		      \
 									      \
 DEFINE_SHOW_ATTRIBUTE(__name)
 
-#define DEFINE_SHOW_ATTRIBUTE(__name)					      \
-static int __name ## _open(struct inode *inode, struct file *file)	      \
-{									      \
-	return single_open(file, __name ## _show, inode->i_private);	      \
-}									      \
-									      \
-static const struct file_operations __name ## _fops = {			      \
-	.open		= __name ## _open,				      \
-	.read		= seq_read,					      \
-	.llseek		= seq_lseek,					      \
-	.release	= single_release,				      \
-}									      \
-
 static int features_show(struct seq_file *f, void *ptr)
 {
 	struct hci_dev *hdev = f->private;