Add "no BKL needed" comments to several drivers
This documents the fact that somebody looked at the relevant open()
functions and concluded that, due to their trivial nature, no locking was
needed.
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
diff --git a/drivers/char/cs5535_gpio.c b/drivers/char/cs5535_gpio.c
index c0a4a0b..628e3d3 100644
--- a/drivers/char/cs5535_gpio.c
+++ b/drivers/char/cs5535_gpio.c
@@ -153,6 +153,8 @@
return count;
}
+/* No BKL needed here - "mask" is the only global resource used
+ here and it's a boot-time parameter */
static int cs5535_gpio_open(struct inode *inode, struct file *file)
{
u32 m = iminor(inode);
diff --git a/drivers/char/dtlk.c b/drivers/char/dtlk.c
index abde6dd..433388c 100644
--- a/drivers/char/dtlk.c
+++ b/drivers/char/dtlk.c
@@ -288,6 +288,8 @@
}
}
+/* No BKL needed here; "dtlk_busy" is the only global resource,
+ and it is not ever set by anybody (test is broken) */
static int dtlk_open(struct inode *inode, struct file *file)
{
TRACE_TEXT("(dtlk_open");
diff --git a/drivers/char/pc8736x_gpio.c b/drivers/char/pc8736x_gpio.c
index ecfaf18..8715dc9 100644
--- a/drivers/char/pc8736x_gpio.c
+++ b/drivers/char/pc8736x_gpio.c
@@ -212,6 +212,7 @@
.gpio_current = pc8736x_gpio_current
};
+/* No BKL needed here; no global resources accessed */
static int pc8736x_gpio_open(struct inode *inode, struct file *file)
{
unsigned m = iminor(inode);
diff --git a/drivers/char/ppdev.c b/drivers/char/ppdev.c
index 3aab837..ce19875 100644
--- a/drivers/char/ppdev.c
+++ b/drivers/char/ppdev.c
@@ -633,6 +633,7 @@
return 0;
}
+/* No BKL needed here: only local resources used */
static int pp_open (struct inode * inode, struct file * file)
{
unsigned int minor = iminor(inode);
diff --git a/drivers/char/scx200_gpio.c b/drivers/char/scx200_gpio.c
index 99e5272..be2c623 100644
--- a/drivers/char/scx200_gpio.c
+++ b/drivers/char/scx200_gpio.c
@@ -46,6 +46,7 @@
};
EXPORT_SYMBOL_GPL(scx200_gpio_ops);
+/* No BKL needed here: no global resources used */
static int scx200_gpio_open(struct inode *inode, struct file *file)
{
unsigned m = iminor(inode);
diff --git a/drivers/char/tb0219.c b/drivers/char/tb0219.c
index 4c431cb..db8c2ca 100644
--- a/drivers/char/tb0219.c
+++ b/drivers/char/tb0219.c
@@ -232,6 +232,7 @@
return i;
}
+/* No BKL needed here; no global resources accessed */
static int tanbac_tb0219_open(struct inode *inode, struct file *file)
{
unsigned int minor;
diff --git a/drivers/char/vr41xx_giu.c b/drivers/char/vr41xx_giu.c
index e5ed091..412937f 100644
--- a/drivers/char/vr41xx_giu.c
+++ b/drivers/char/vr41xx_giu.c
@@ -543,6 +543,8 @@
return i;
}
+/* No BKL needed here; only global (giu_nr_pins) is only set
+ at probe time */
static int gpio_open(struct inode *inode, struct file *file)
{
unsigned int pin;