pinctrl: enhance pinctrl_get() to handle multiple functions

At present, pinctrl_get() assumes that all matching mapping table entries
have the same "function" value, albeit potentially applied to different
pins/groups.

This change removes this restriction; pinctrl_get() can now handle a set
of mapping tables where different functions are applied to the various
pins/groups.

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

3 files changed, 14 insertions, 27 deletions

diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h
index 7551611666f8..8164e7b4182b 100644
--- a/drivers/pinctrl/core.h
+++ b/drivers/pinctrl/core.h
@@ -53,8 +53,6 @@ struct pinctrl_dev {
  *      to keep track of nested use cases
  * @pctldev: pin control device handling this pin control handle
  * @mutex: a lock for the pin control state holder
- * @func_selector: the function selector for the pinmux device handling
- *      this pinmux
  * @groups: the group selectors for the pinmux device and
  *      selector combination handling this pinmux, this is a list that
  *      will be traversed on all pinmux operations such as
@@ -67,7 +65,6 @@ struct pinctrl {
         struct pinctrl_dev *pctldev;
         struct mutex mutex;
 #ifdef CONFIG_PINMUX
-        unsigned func_selector;
         struct list_head groups;
 #endif
 };
diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c
index 2a405618b448..f409f161ea1d 100644
--- a/drivers/pinctrl/pinmux.c
+++ b/drivers/pinctrl/pinmux.c
@@ -33,10 +33,13 @@
 /**
  * struct pinmux_group - group list item for pinmux groups
  * @node: pinmux group list node
+ * @func_selector: the function selector for the pinmux device handling
+ *      this pinmux
  * @group_selector: the group selector for this group
  */
 struct pinmux_group {
         struct list_head node;
+        unsigned func_selector;
         unsigned group_selector;
 };
 
@@ -476,24 +479,11 @@ static int pinmux_enable_muxmap(struct pinctrl_dev *pctldev,
         if (ret < 0)
                 return ret;
 
-        /*
-         * If the function selector is already set, it needs to be identical,
-         * we support several groups with one function but not several
-         * functions with one or several groups in the same pinmux.
-         */
-        if (p->func_selector != UINT_MAX &&
-            p->func_selector != func_selector) {
-                dev_err(pctldev->dev,
-                        "dual function defines in the map for device %s\n",
-                       devname);
-                return -EINVAL;
-        }
-        p->func_selector = func_selector;
-
         /* Now add this group selector, we may have many of them */
         grp = kmalloc(sizeof(*grp), GFP_KERNEL);
         if (!grp)
                 return -ENOMEM;
+        grp->func_selector = func_selector;
         grp->group_selector = group_selector;
         ret = acquire_pins(pctldev, devname, group_selector);
         if (ret) {
@@ -554,7 +544,7 @@ int pinmux_enable(struct pinctrl *p)
         int ret;
 
         list_for_each_entry(grp, &p->groups, node) {
-                ret = ops->enable(pctldev, p->func_selector,
+                ret = ops->enable(pctldev, grp->func_selector,
                                   grp->group_selector);
                 if (ret)
                         /*
@@ -576,7 +566,7 @@ void pinmux_disable(struct pinctrl *p)
         struct pinmux_group *grp;
 
         list_for_each_entry(grp, &p->groups, node) {
-                ops->disable(pctldev, p->func_selector,
+                ops->disable(pctldev, grp->func_selector,
                              grp->group_selector);
         }
 }
@@ -654,21 +644,22 @@ void pinmux_dbg_show(struct seq_file *s, struct pinctrl *p)
         const struct pinmux_ops *pmxops;
         const struct pinctrl_ops *pctlops;
         struct pinmux_group *grp;
+        const char *sep = "";
 
         pmxops = pctldev->desc->pmxops;
         pctlops = pctldev->desc->pctlops;
 
-        seq_printf(s, " function: %s (%u),",
-                   pmxops->get_function_name(pctldev,
-                                             p->func_selector),
-                   p->func_selector);
-
         seq_printf(s, " groups: [");
         list_for_each_entry(grp, &p->groups, node) {
-                seq_printf(s, " %s (%u)",
+                seq_printf(s, "%s%s (%u)=%s (%u)",
+                           sep,
                            pctlops->get_group_name(pctldev,
                                                    grp->group_selector),
-                           grp->group_selector);
+                           grp->group_selector,
+                           pmxops->get_function_name(pctldev,
+                                                     grp->func_selector),
+                           grp->func_selector);
+                sep = ", ";
         }
         seq_printf(s, " ]");
 }
diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h
index 84b8fe946b5c..822febb2d968 100644
--- a/drivers/pinctrl/pinmux.h
+++ b/drivers/pinctrl/pinmux.h
@@ -23,7 +23,6 @@ int pinmux_gpio_direction(struct pinctrl_dev *pctldev,
                           unsigned pin, bool input);
 static inline void pinmux_init_pinctrl_handle(struct pinctrl *p)
 {
-        p->func_selector = UINT_MAX;
         INIT_LIST_HEAD(&p->groups);
 }
 int pinmux_apply_muxmap(struct pinctrl_dev *pctldev,