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>

1 files changed, 16 insertions, 7 deletions

diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h
index 0bc52ecaf710..5691d312e15a 100644
--- a/drivers/pinctrl/core.h
+++ b/drivers/pinctrl/core.h
@@ -49,22 +49,31 @@ struct pinctrl_dev {
  * struct pinctrl - per-device pin control state holder
  * @node: global list node
  * @dev: the device using this pin control handle
- * @state: the state name passed to pinctrl_get()
- * @usecount: the number of active users of this pin controller setting, used
- *	to keep track of nested use cases
- * @settings: a list of settings for this device/state
+ * @states: a list of states for this device
+ * @state: the current state
  */
 struct pinctrl {
 	struct list_head node;
 	struct device *dev;
-	const char *state;
-	unsigned usecount;
+	struct list_head states;
+	struct pinctrl_state *state;
+};
+
+/**
+ * struct pinctrl_state - a pinctrl state for a device
+ * @node: list not for struct pinctrl's @states field
+ * @name: the name of this state
+ * @settings: a list of settings for this state
+ */
+struct pinctrl_state {
+	struct list_head node;
+	const char *name;
 	struct list_head settings;
 };
 
 /**
  * struct pinctrl_setting - an individual mux setting
- * @node: list node for struct pinctrl's @settings field
+ * @node: list node for struct pinctrl_settings's @settings field
  * @pctldev: pin control device handling to be programmed
  * @group_selector: the group selector to program
  * @func_selector: the function selector to program