From: Nicola Mazzucato <nicola.mazzucato@arm.com>
Date: Tue, 8 Dec 2020 17:42:27 +0000 (+0000)
Subject: opp: of: Allow empty opp-table with opp-shared
X-Git-Tag: microblaze-v5.12~154^2~4^2^2
X-Git-Url: http://git.monstr.eu/?p=linux-2.6-microblaze.git;a=commitdiff_plain;h=6ee70e8c34e37a34f4dc2c8bc06febffd375fac4

opp: of: Allow empty opp-table with opp-shared

The opp binding now allows to have an empty opp table and shared-opp to
still describe that devices share v/f lines.

When initialising an empty opp table, allow such case by:
- treating such conditions with warnings in place of errors
- don't fail on empty table

Signed-off-by: Nicola Mazzucato <nicola.mazzucato@arm.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---

diff --git a/drivers/opp/of.c b/drivers/opp/of.c
index 874b58756220..96113fc0e18c 100644
--- a/drivers/opp/of.c
+++ b/drivers/opp/of.c
@@ -169,7 +169,8 @@ static void _opp_table_alloc_required_tables(struct opp_table *opp_table,
 	/* Traversing the first OPP node is all we need */
 	np = of_get_next_available_child(opp_np, NULL);
 	if (!np) {
-		dev_err(dev, "Empty OPP table\n");
+		dev_warn(dev, "Empty OPP table\n");
+
 		return;
 	}
 
@@ -377,7 +378,9 @@ int dev_pm_opp_of_find_icc_paths(struct device *dev,
 	struct icc_path **paths;
 
 	ret = _bandwidth_supported(dev, opp_table);
-	if (ret <= 0)
+	if (ret == -EINVAL)
+		return 0; /* Empty OPP table is a valid corner-case, let's not fail */
+	else if (ret <= 0)
 		return ret;
 
 	ret = 0;