[PATCH 2/2] mfd: twl4030-power: fix undefined resconfig value checks

[Aaro Koskinen <aaro.koskinen@nokia.com>]

The code tries to skip values initialized with -1, but since the values
are unsigned the comparison is always true.

The patch eliminates the following compiler warnings:

drivers/mfd/twl4030-power.c: In function 'twl4030_configure_resource':
drivers/mfd/twl4030-power.c:338: warning: comparison is always true due to limited range of data type
drivers/mfd/twl4030-power.c:358: warning: comparison is always true due to limited range of data type
drivers/mfd/twl4030-power.c:363: warning: comparison is always true due to limited range of data type

Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
---
 drivers/mfd/twl4030-power.c |    6 +++---
 include/linux/i2c/twl4030.h |    1 +
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/mfd/twl4030-power.c b/drivers/mfd/twl4030-power.c
index eae6cda..2f7c805 100644
--- a/drivers/mfd/twl4030-power.c
+++ b/drivers/mfd/twl4030-power.c
@@ -335,7 +335,7 @@ static int __init twl4030_configure_resource(struct twl4030_resconfig *rconfig)
 		return err;
 	}
 
-	if (rconfig->devgroup >= 0) {
+	if (rconfig->devgroup != TWL4030_RESCONFIG_UNDEF) {
 		grp &= ~DEVGROUP_MASK;
 		grp |= rconfig->devgroup << DEVGROUP_SHIFT;
 		err = twl4030_i2c_write_u8(TWL4030_MODULE_PM_RECEIVER,
@@ -355,12 +355,12 @@ static int __init twl4030_configure_resource(struct twl4030_resconfig *rconfig)
 		return err;
 	}
 
-	if (rconfig->type >= 0) {
+	if (rconfig->type != TWL4030_RESCONFIG_UNDEF) {
 		type &= ~TYPE_MASK;
 		type |= rconfig->type << TYPE_SHIFT;
 	}
 
-	if (rconfig->type2 >= 0) {
+	if (rconfig->type2 != TWL4030_RESCONFIG_UNDEF) {
 		type &= ~TYPE2_MASK;
 		type |= rconfig->type2 << TYPE2_SHIFT;
 	}
diff --git a/include/linux/i2c/twl4030.h b/include/linux/i2c/twl4030.h
index 508824e..99e5d7b 100644
--- a/include/linux/i2c/twl4030.h
+++ b/include/linux/i2c/twl4030.h
@@ -391,6 +391,7 @@ struct twl4030_resconfig {
 	u8 devgroup;	/* Processor group that Power resource belongs to */
 	u8 type;	/* Power resource addressed, 6 / broadcast message */
 	u8 type2;	/* Power resource addressed, 3 / broadcast message */
+#define TWL4030_RESCONFIG_UNDEF	((u8)-1)
 };
 
 struct twl4030_power_data {
-- 
1.6.0.4