kernel/irq: Extend lockdep class for request mutex

The IRQ code already has support for lockdep class for the lock mutex
in an interrupt descriptor. Extend this to add a second class for the
request mutex in the descriptor. Not having a class is resulting in
false positive splats in some code paths.

Signed-off-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: linus.walleij@linaro.org
Cc: grygorii.strashko@ti.com
Cc: f.fainelli@gmail.com
Link: https://lkml.kernel.org/r/1512234664-21555-1-git-send-email-andrew@lunn.ch

1 files changed, 21 insertions, 12 deletions

diff --git a/include/linux/gpio/driver.h b/include/linux/gpio/driver.h
index 55e672592fa9..7258cd676df4 100644
--- a/include/linux/gpio/driver.h
+++ b/include/linux/gpio/driver.h
@@ -66,9 +66,10 @@ struct gpio_irq_chip {
         /**
          * @lock_key:
          *
-         * Per GPIO IRQ chip lockdep class.
+         * Per GPIO IRQ chip lockdep classes.
          */
         struct lock_class_key *lock_key;
+        struct lock_class_key *request_key;
 
         /**
          * @parent_handler:
@@ -323,7 +324,8 @@ extern const char *gpiochip_is_requested(struct gpio_chip *chip,
 
 /* add/remove chips */
 extern int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
-                                      struct lock_class_key *lock_key);
+                                      struct lock_class_key *lock_key,
+                                      struct lock_class_key *request_key);
 
 /**
  * gpiochip_add_data() - register a gpio_chip
@@ -350,11 +352,13 @@ extern int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
  */
 #ifdef CONFIG_LOCKDEP
 #define gpiochip_add_data(chip, data) ({                \
-                static struct lock_class_key key;       \
-                gpiochip_add_data_with_key(chip, data, &key);   \
+                static struct lock_class_key lock_key;  \
+                static struct lock_class_key request_key;         \
+                gpiochip_add_data_with_key(chip, data, &lock_key, \
+                                           &request_key);         \
         })
 #else
-#define gpiochip_add_data(chip, data) gpiochip_add_data_with_key(chip, data, NULL)
+#define gpiochip_add_data(chip, data) gpiochip_add_data_with_key(chip, data, NULL, NULL)
 #endif
 
 static inline int gpiochip_add(struct gpio_chip *chip)
@@ -429,7 +433,8 @@ int gpiochip_irqchip_add_key(struct gpio_chip *gpiochip,
                              irq_flow_handler_t handler,
                              unsigned int type,
                              bool threaded,
-                             struct lock_class_key *lock_key);
+                             struct lock_class_key *lock_key,
+                             struct lock_class_key *request_key);
 
 #ifdef CONFIG_LOCKDEP
 
@@ -445,10 +450,12 @@ static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
                                        irq_flow_handler_t handler,
                                        unsigned int type)
 {
-        static struct lock_class_key key;
+        static struct lock_class_key lock_key;
+        static struct lock_class_key request_key;
 
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, false, &key);
+                                        handler, type, false,
+                                        &lock_key, &request_key);
 }
 
 static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
@@ -458,10 +465,12 @@ static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
                           unsigned int type)
 {
 
-        static struct lock_class_key key;
+        static struct lock_class_key lock_key;
+        static struct lock_class_key request_key;
 
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, true, &key);
+                                        handler, type, true,
+                                        &lock_key, &request_key);
 }
 #else
 static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
@@ -471,7 +480,7 @@ static inline int gpiochip_irqchip_add(struct gpio_chip *gpiochip,
                                        unsigned int type)
 {
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, false, NULL);
+                                        handler, type, false, NULL, NULL);
 }
 
 static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
@@ -481,7 +490,7 @@ static inline int gpiochip_irqchip_add_nested(struct gpio_chip *gpiochip,
                           unsigned int type)
 {
         return gpiochip_irqchip_add_key(gpiochip, irqchip, first_irq,
-                                        handler, type, true, NULL);
+                                        handler, type, true, NULL, NULL);
 }
 #endif /* CONFIG_LOCKDEP */