For legacy reasons, we do not fail the MCI registration when a regulator
can't be immediately requested, but we at least print a warning when
this happens. Add a comment guiding the user into how to resolve the
warning.
Signed-off-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
---
drivers/mci/mci-core.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/drivers/mci/mci-core.c b/drivers/mci/mci-core.c
index b8f71e15986e..8c08a4f61f63 100644
--- a/drivers/mci/mci-core.c
+++ b/drivers/mci/mci-core.c
@@ -1941,6 +1941,16 @@ int mci_register(struct mci_host *host)
host->supply = regulator_get(hw_dev, "vmmc");
if (IS_ERR(host->supply)) {
+ /*
+ * If you know your regulator to be always online on boot, but
+ * can't easily add a barebox driver for it, you may use
+ * barebox,allow-dummy-supply in your board's regulator device
+ * tree node to side step this warning.
+ *
+ * If you run into this warning, because your regulator driver
+ * hasn't probed the device yet, consider enabling deep probe
+ * for your board, to probe dependencies on demand.
+ */
dev_warn(hw_dev, "Failed to get 'vmmc' regulator (ignored).\n");
host->supply = NULL;
}
--
2.30.2
