linux-kernel - [PATCH] regulator: rc5t583: Simplify rc5t583_set_voltage_time

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Message-ID: <1339058289.5274.0.camel@phoenix>
Date:	Thu, 07 Jun 2012 16:38:09 +0800
From:	Axel Lin <axel.lin@...il.com>
To:	linux-kernel@...r.kernel.org
Cc:	Laxman Dewangan <ldewangan@...dia.com>, Liam Girdwood <lrg@...com>,
	Mark Brown <broonie@...nsource.wolfsonmicro.com>
Subject: [PATCH] regulator: rc5t583: Simplify rc5t583_set_voltage_time_sel
 implementation

For linear mappings, we can use below equation to get the voltage difference
between new_selector and old_selector:

abs(new_selector - old_selector) * rdev->desc->uV_step

Signed-off-by: Axel Lin <axel.lin@...il.com>
---
 drivers/regulator/rc5t583-regulator.c |   14 +++-----------
 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/drivers/regulator/rc5t583-regulator.c b/drivers/regulator/rc5t583-regulator.c
index 1d34e64..332eae8 100644
--- a/drivers/regulator/rc5t583-regulator.c
+++ b/drivers/regulator/rc5t583-regulator.c
@@ -70,18 +70,10 @@ static int rc5t583_set_voltage_time_sel(struct regulator_dev *rdev,
 		unsigned int old_selector, unsigned int new_selector)
 {
 	struct rc5t583_regulator *reg = rdev_get_drvdata(rdev);
-	int old_uV, new_uV;
-	old_uV = regulator_list_voltage_linear(rdev, old_selector);
 
-	if (old_uV < 0)
-		return old_uV;
-
-	new_uV = regulator_list_voltage_linear(rdev, new_selector);
-	if (new_uV < 0)
-		return new_uV;
-
-	return DIV_ROUND_UP(abs(old_uV - new_uV),
-				reg->reg_info->change_uv_per_us);
+	return DIV_ROUND_UP(abs(new_selector - old_selector) *
+			    rdev->desc->uV_step,
+			    reg->reg_info->change_uv_per_us);
 }
 
 
-- 
1.7.9.5



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