linux-kernel - [PATCH 3/4] regulator: core: optimize devm_regulator_bulk

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Message-Id: <20170203231619.8013-3-dmitry.torokhov@gmail.com>
Date:   Fri,  3 Feb 2017 15:16:18 -0800
From:   Dmitry Torokhov <dmitry.torokhov@...il.com>
To:     Mark Brown <broonie@...nel.org>
Cc:     Liam Girdwood <lgirdwood@...il.com>, linux-kernel@...r.kernel.org,
        Bjorn Andersson <bjorn.andersson@...ymobile.com>
Subject: [PATCH 3/4] regulator: core: optimize devm_regulator_bulk_get()

When performing this bulk operation, there is no need to track every supply
individually. It is more efficient to treat entire group as a single
managed resource.

Signed-off-by: Dmitry Torokhov <dmitry.torokhov@...il.com>
---
 drivers/regulator/devres.c | 45 +++++++++++++++++++++++++--------------------
 1 file changed, 25 insertions(+), 20 deletions(-)

diff --git a/drivers/regulator/devres.c b/drivers/regulator/devres.c
index 965d1d31ec8c..784e3bf32210 100644
--- a/drivers/regulator/devres.c
+++ b/drivers/regulator/devres.c
@@ -120,6 +120,18 @@ void devm_regulator_put(struct regulator *regulator)
 }
 EXPORT_SYMBOL_GPL(devm_regulator_put);
 
+struct regulator_bulk_devres {
+	struct regulator_bulk_data *consumers;
+	int num_consumers;
+};
+
+static void devm_regulator_bulk_release(struct device *dev, void *res)
+{
+	struct regulator_bulk_devres *devres = res;
+
+	regulator_bulk_free(devres->num_consumers, devres->consumers);
+}
+
 /**
  * devm_regulator_bulk_get - managed get multiple regulator consumers
  *
@@ -138,29 +150,22 @@ EXPORT_SYMBOL_GPL(devm_regulator_put);
 int devm_regulator_bulk_get(struct device *dev, int num_consumers,
 			    struct regulator_bulk_data *consumers)
 {
-	int i;
+	struct regulator_bulk_devres *devres;
 	int ret;
 
-	for (i = 0; i < num_consumers; i++)
-		consumers[i].consumer = NULL;
-
-	for (i = 0; i < num_consumers; i++) {
-		consumers[i].consumer = devm_regulator_get(dev,
-							   consumers[i].supply);
-		if (IS_ERR(consumers[i].consumer)) {
-			ret = PTR_ERR(consumers[i].consumer);
-			dev_err(dev, "Failed to get supply '%s': %d\n",
-				consumers[i].supply, ret);
-			consumers[i].consumer = NULL;
-			goto err;
-		}
-	}
-
-	return 0;
+	devres = devres_alloc(devm_regulator_bulk_release,
+			      sizeof(*devres), GFP_KERNEL);
+	if (!devres)
+		return -ENOMEM;
 
-err:
-	for (i = 0; i < num_consumers && consumers[i].consumer; i++)
-		devm_regulator_put(consumers[i].consumer);
+	ret = regulator_bulk_get(dev, num_consumers, consumers);
+	if (!ret) {
+		devres->consumers = consumers;
+		devres->num_consumers = num_consumers;
+		devres_add(dev, devres);
+	} else {
+		devres_free(devres);
+	}
 
 	return ret;
 }
-- 
2.11.0.483.g087da7b7c-goog