pinctrl: introduce generic pin config

This is a split-off from the earlier patch set which adds generic
pin configuration for the pin controllers that want it. Since
we may have a system with mixed generic and custom pin controllers,
we pass a boolean in the pin controller ops vtable to indicate
if it is generic.

ChangeLog v1->v5:
- Follow parent patch versioning number system.
- Document the semantic meaning of return values from pin config
  get functions, so we can iterate over pins and check their
  properties from debugfs as part of the generic config code.
- Use proper cast functions in the generic debugfs pin config
  file.
- Expand generic config to optionally cover groups too.
ChangeLog v5->v6:
- Update to match underlying changes.
ChangeLog v6->v7:
- Drop DRIVE_OFF parameter, use bias high impedance for this
- Delete argument for drive modes push-pull, od and os. These
  are now just state transitions.
- Delete slew rate rising/falling due to discussions on on
  proper semantics
- Drop config wakeup, struct irq_chip does this for now, add
  back if need be.
- Set PIN_CONFIG_END to 0x7fff making room for custom config
  parameters from 0x8000 and up.
- Prefix accessor functions with pinconf_

drivers/pinctrl/pinconf.h

@@ -14,20 +14,26 @@
 #ifdef CONFIG_PINCONF
 
 int pinconf_check_ops(struct pinctrl_dev *pctldev);
-
 int pinconf_validate_map(struct pinctrl_map const *map, int i);
-
 int pinconf_map_to_setting(struct pinctrl_map const *map,
 			  struct pinctrl_setting *setting);
 void pinconf_free_setting(struct pinctrl_setting const *setting);
 int pinconf_apply_setting(struct pinctrl_setting const *setting);
-
 void pinconf_show_map(struct seq_file *s, struct pinctrl_map const *map);
 void pinconf_show_setting(struct seq_file *s,
 			  struct pinctrl_setting const *setting);
 void pinconf_init_device_debugfs(struct dentry *devroot,
 				 struct pinctrl_dev *pctldev);
 
+/*
+ * You will only be interested in these if you're using PINCONF
+ * so don't supply any stubs for these.
+ */
+int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin,
+			   unsigned long *config);
+int pin_config_group_get(const char *dev_name, const char *pin_group,
+			 unsigned long *config);
+
 #else
 
 static inline int pinconf_check_ops(struct pinctrl_dev *pctldev)
@@ -71,3 +77,34 @@ static inline void pinconf_init_device_debugfs(struct dentry *devroot,
 }
 
 #endif
+
+/*
+ * The following functions are available if the driver uses the generic
+ * pin config.
+ */
+
+#ifdef CONFIG_GENERIC_PINCONF
+
+void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev,
+			      struct seq_file *s, unsigned pin);
+
+void pinconf_generic_dump_group(struct pinctrl_dev *pctldev,
+			      struct seq_file *s, const char *gname);
+
+#else
+
+static inline void pinconf_generic_dump_pin(struct pinctrl_dev *pctldev,
+					    struct seq_file *s,
+					    unsigned pin)
+{
+	return;
+}
+
+static inline void pinconf_generic_dump_group(struct pinctrl_dev *pctldev,
+					      struct seq_file *s,
+					      const char *gname)
+{
+	return;
+}
+
+#endif