pinctrl: API changes to support multiple states per device

The API model is changed from:

p = pinctrl_get(dev, "state1");
pinctrl_enable(p);
...
pinctrl_disable(p);
pinctrl_put(p);
p = pinctrl_get(dev, "state2");
pinctrl_enable(p);
...
pinctrl_disable(p);
pinctrl_put(p);

to this:

p = pinctrl_get(dev);
s1 = pinctrl_lookup_state(p, "state1");
s2 = pinctrl_lookup_state(p, "state2");
pinctrl_select_state(p, s1);
...
pinctrl_select_state(p, s2);
...
pinctrl_put(p);

This allows devices to directly transition between states without
disabling the pin controller programming and put()/get()ing the
configuration data each time. This model will also better suit pinconf
programming, which doesn't have a concept of "disable".

The special-case hogging feature of pin controllers is re-written to use
the regular APIs instead of special-case code. Hence, the pinmux-hogs
debugfs file is removed; see the top-level pinctrl-handles files for
equivalent data.

Signed-off-by: Stephen Warren <swarren@nvidia.com>
Acked-by: Dong Aisheng <dong.aisheng@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

2 files changed, 53 insertions, 13 deletions

diff --git a/include/linux/pinctrl/consumer.h b/include/linux/pinctrl/consumer.h
index 3086594..9ad5896 100644
--- a/include/linux/pinctrl/consumer.h
+++ b/include/linux/pinctrl/consumer.h
@@ -12,12 +12,14 @@
 #ifndef __LINUX_PINCTRL_CONSUMER_H
 #define __LINUX_PINCTRL_CONSUMER_H
 
+#include <linux/err.h>
 #include <linux/list.h>
 #include <linux/seq_file.h>
 #include "pinctrl.h"
 
 /* This struct is private to the core and should be regarded as a cookie */
 struct pinctrl;
+struct pinctrl_state;
 
 #ifdef CONFIG_PINCTRL
 
@@ -26,10 +28,13 @@ extern int pinctrl_request_gpio(unsigned gpio);
 extern void pinctrl_free_gpio(unsigned gpio);
 extern int pinctrl_gpio_direction_input(unsigned gpio);
 extern int pinctrl_gpio_direction_output(unsigned gpio);
-extern struct pinctrl * __must_check pinctrl_get(struct device *dev, const char *name);
+
+extern struct pinctrl * __must_check pinctrl_get(struct device *dev);
 extern void pinctrl_put(struct pinctrl *p);
-extern int pinctrl_enable(struct pinctrl *p);
-extern void pinctrl_disable(struct pinctrl *p);
+extern struct pinctrl_state * __must_check pinctrl_lookup_state(
+							struct pinctrl *p,
+							const char *name);
+extern int pinctrl_select_state(struct pinctrl *p, struct pinctrl_state *s);
 
 #else /* !CONFIG_PINCTRL */
 
@@ -52,7 +57,7 @@ static inline int pinctrl_gpio_direction_output(unsigned gpio)
 	return 0;
 }
 
-static inline struct pinctrl * __must_check pinctrl_get(struct device *dev, const char *name)
+static inline struct pinctrl * __must_check pinctrl_get(struct device *dev)
 {
 	return NULL;
 }
@@ -61,17 +66,53 @@ static inline void pinctrl_put(struct pinctrl *p)
 {
 }
 
-static inline int pinctrl_enable(struct pinctrl *p)
+static inline struct pinctrl_state * __must_check pinctrl_lookup_state(
+							struct pinctrl *p,
+							const char *name)
 {
-	return 0;
+	return NULL;
 }
 
-static inline void pinctrl_disable(struct pinctrl *p)
+static inline int pinctrl_select_state(struct pinctrl *p,
+				       struct pinctrl_state *s)
 {
+	return 0;
 }
 
 #endif /* CONFIG_PINCTRL */
 
+static inline struct pinctrl * __must_check pinctrl_get_select(
+					struct device *dev, const char *name)
+{
+	struct pinctrl *p;
+	struct pinctrl_state *s;
+	int ret;
+
+	p = pinctrl_get(dev);
+	if (IS_ERR(p))
+		return p;
+
+	s = pinctrl_lookup_state(p, name);
+	if (IS_ERR(s)) {
+		pinctrl_put(p);
+		return ERR_PTR(PTR_ERR(s));
+	}
+
+	ret = pinctrl_select_state(p, s);
+	if (ret < 0) {
+		pinctrl_put(p);
+		return ERR_PTR(ret);
+	}
+
+	return p;
+}
+
+static inline struct pinctrl * __must_check pinctrl_get_select_default(
+					struct device *dev)
+{
+	return pinctrl_get_select(dev, PINCTRL_STATE_DEFAULT);
+}
+
 #ifdef CONFIG_PINCONF
 
 extern int pin_config_get(const char *dev_name, const char *name,
diff --git a/include/linux/pinctrl/machine.h b/include/linux/pinctrl/machine.h
index 20e9735..05d25c8 100644
--- a/include/linux/pinctrl/machine.h
+++ b/include/linux/pinctrl/machine.h
@@ -21,23 +21,22 @@
  *	same name as the pin controllers own dev_name(), the map entry will be
  *	hogged by the driver itself upon registration
  * @name: the name of this specific map entry for the particular machine.
- *	This is the second parameter passed to pinmux_get() when you want
- *	to have several mappings to the same device
+ *	This is the parameter passed to pinmux_lookup_state()
  * @ctrl_dev_name: the name of the device controlling this specific mapping,
  *	the name must be the same as in your struct device*
- * @function: a function in the driver to use for this mapping, the driver
- *	will lookup the function referenced by this ID on the specified
- *	pin control device
  * @group: sometimes a function can map to different pin groups, so this
  *	selects a certain specific pin group to activate for the function, if
  *	left as NULL, the first applicable group will be used
+ * @function: a function in the driver to use for this mapping, the driver
+ *	will lookup the function referenced by this ID on the specified
+ *	pin control device
  */
 struct pinctrl_map {
 	const char *dev_name;
 	const char *name;
 	const char *ctrl_dev_name;
-	const char *function;
 	const char *group;
+	const char *function;
 };
 
 /*