pinctrl: implement pinctrl deferred probing

If drivers try to obtain pinctrl handles for a pin controller that
has not yet registered to the subsystem, we need to be able to
back out and retry with deferred probing. So let's return
-EPROBE_DEFER whenever this location fails. Also downgrade the
errors to info, maybe we will even set them to debug once the
deferred probing is commonplace.

Cc: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Stephen Warren <swarren@wwwdotorg.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 3 insertions, 3 deletions

diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c
index 5ef2feb44395..fcb1de45473c 100644
--- a/drivers/pinctrl/devicetree.c
+++ b/drivers/pinctrl/devicetree.c
@@ -121,11 +121,11 @@ static int dt_to_map_one_config(struct pinctrl *p, const char *statename,
         for (;;) {
                 np_pctldev = of_get_next_parent(np_pctldev);
                 if (!np_pctldev || of_node_is_root(np_pctldev)) {
-                        dev_err(p->dev, "could not find pctldev for node %s\n",
+                        dev_info(p->dev, "could not find pctldev for node %s, deferring probe\n",
                                 np_config->full_name);
                         of_node_put(np_pctldev);
-                        /* FIXME: This should trigger deferrered probe */
-                        return -ENODEV;
+                        /* OK let's just assume this will appear later then */
+                        return -EPROBE_DEFER;
                 }
                 pctldev = find_pinctrl_by_of_node(np_pctldev);
                 if (pctldev)