From 17104ca2713ba443f9a02a7c4090514ad1e46ee9 Mon Sep 17 00:00:00 2001
From: Nathan Chancellor <natechancellor@gmail.com>
Date: Thu, 7 Mar 2019 10:16:04 -0700
Subject: [PATCH] iio: adc: stmpe-adc: Shuffle an if statement around in
 stmpe_adc_isr

When building with -Wsometimes-uninitialized, Clang warns:

drivers/iio/adc/stmpe-adc.c:204:13: warning: variable 'data' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized]

Clang can't tell that data will never be used uninitialized because the
two if statements take care of all cases. Remove the first if statement
and make it the else branch of the second one so that it is apparent to
Clang that all cases are covered.

Link: https://github.com/ClangBuiltLinux/linux/issues/387
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: NIck Desaulniers <ndesaulniers@google.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
---
 drivers/iio/adc/stmpe-adc.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/iio/adc/stmpe-adc.c b/drivers/iio/adc/stmpe-adc.c
index 37f4b74a5d323..7921f827c6ec4 100644
--- a/drivers/iio/adc/stmpe-adc.c
+++ b/drivers/iio/adc/stmpe-adc.c
@@ -184,9 +184,6 @@ static irqreturn_t stmpe_adc_isr(int irq, void *dev_id)
 	struct stmpe_adc *info = (struct stmpe_adc *)dev_id;
 	u16 data;
 
-	if (info->channel > STMPE_TEMP_CHANNEL)
-		return IRQ_NONE;
-
 	if (info->channel <= STMPE_ADC_LAST_NR) {
 		int int_sta;
 
@@ -205,6 +202,8 @@ static irqreturn_t stmpe_adc_isr(int irq, void *dev_id)
 		/* Read value */
 		stmpe_block_read(info->stmpe, STMPE_REG_TEMP_DATA, 2,
 				(u8 *) &data);
+	} else {
+		return IRQ_NONE;
 	}
 
 	info->value = (u32) be16_to_cpu(data);
-- 
GitLab