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>
diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c
index 7ff8690..59027ab 100644
--- a/drivers/pinctrl/core.c
+++ b/drivers/pinctrl/core.c
@@ -518,11 +518,14 @@
setting->pctldev = get_pinctrl_dev_from_devname(map->ctrl_dev_name);
if (setting->pctldev == NULL) {
- dev_err(p->dev, "unknown pinctrl device %s in map entry",
+ dev_info(p->dev, "unknown pinctrl device %s in map entry, deferring probe",
map->ctrl_dev_name);
kfree(setting);
- /* Eventually, this should trigger deferred probe */
- return -ENODEV;
+ /*
+ * OK let us guess that the driver is not there yet, and
+ * let's defer obtaining this pinctrl handle to later...
+ */
+ return -EPROBE_DEFER;
}
switch (map->type) {
diff --git a/drivers/pinctrl/devicetree.c b/drivers/pinctrl/devicetree.c
index 5ef2feb..fcb1de4 100644
--- a/drivers/pinctrl/devicetree.c
+++ b/drivers/pinctrl/devicetree.c
@@ -121,11 +121,11 @@
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)