pinctrl: conjure names for unnamed pins

If pins with blank names are registered, we assign them names on-the-fly
on the form "PINn" where n is the pin number for that pin on the specific
controller.

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

2 files changed, 13 insertions, 2 deletions

diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 160fb5aae591..9e32ea311432 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -158,6 +158,8 @@ static void pinctrl_free_pindescs(struct pinctrl_dev *pctldev,
                 if (pindesc != NULL) {
                         radix_tree_delete(&pctldev->pin_desc_tree,
                                           pins[i].number);
+                        if (pindesc->dynamic_name)
+                                kfree(pindesc->name);
                 }
                 kfree(pindesc);
         }
@@ -186,13 +188,20 @@ static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev,
         pindesc->pctldev = pctldev;
 
         /* Copy basic pin info */
-        pindesc->name = name;
+        if (pindesc->name) {
+                pindesc->name = name;
+        } else {
+                pindesc->name = kasprintf(GFP_KERNEL, "PIN%u", number);
+                if (pindesc->name == NULL)
+                        return -ENOMEM;
+                pindesc->dynamic_name = true;
+        }
 
         spin_lock(&pctldev->pin_desc_tree_lock);
         radix_tree_insert(&pctldev->pin_desc_tree, number, pindesc);
         spin_unlock(&pctldev->pin_desc_tree_lock);
         pr_debug("registered pin %d (%s) on %s\n",
-                 number, name ? name : "(unnamed)", pctldev->desc->name);
+                 number, pindesc->name, pctldev->desc->name);
         return 0;
 }
 
diff --git a/drivers/pinctrl/core.h b/drivers/pinctrl/core.h
index 5375582566a5..177a3310547f 100644
--- a/drivers/pinctrl/core.h
+++ b/drivers/pinctrl/core.h
@@ -52,6 +52,7 @@ struct pinctrl_dev {
  * @pctldev: corresponding pin control device
  * @name: a name for the pin, e.g. the name of the pin/pad/finger on a
  *      datasheet or such
+ * @dynamic_name: if the name of this pin was dynamically allocated
  * @lock: a lock to protect the descriptor structure
  * @mux_requested: whether the pin is already requested by pinmux or not
  * @mux_function: a named muxing function for the pin that will be passed to
@@ -60,6 +61,7 @@ struct pinctrl_dev {
 struct pin_desc {
         struct pinctrl_dev *pctldev;
         const char *name;
+        bool dynamic_name;
         spinlock_t lock;
         /* These fields only added when supporting pinmux drivers */
 #ifdef CONFIG_PINMUX