[PATCH 1/1] rt2x00: Avoid using 'char' for signed operations

[Andy Shevchenko]

The default Tx power is defined as 'short' in the data structure.
There is nothing prevents us to use 'short' in the
rt2800_txpower_to_dev(). With 'char' it's implementation defined
signedess and sometimes it may be tricky.

  drivers/net/wireless/ralink/rt2x00/rt2800lib.c: In function 'rt2800_txpower_to_dev':
  include/linux/build_bug.h:16:51: error: negative width in bit-field '<anonymous>'
  ...
  drivers/net/wireless/ralink/rt2x00/rt2800lib.c:4054:24: note: in expansion of macro 'clamp_t'
  4054 |  return clamp_t(char, txpower, MIN_A_TXPOWER, MAX_A_TXPOWER);

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
---
 drivers/net/wireless/ralink/rt2x00/rt2800lib.c | 11 +++++------
 1 file changed, 5 insertions(+), 6 deletions(-)

diff --git a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
index cbbb1a4849cf..d7dffea6df82 100644
--- a/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2800lib.c
@@ -4035,23 +4035,22 @@ static void rt2800_iq_calibrate(struct rt2x00_dev *rt2x00dev, int channel)
 	rt2800_bbp_write(rt2x00dev, 159, cal != 0xff ? cal : 0);
 }
 
-static char rt2800_txpower_to_dev(struct rt2x00_dev *rt2x00dev,
-				  unsigned int channel,
-				  char txpower)
+static short rt2800_txpower_to_dev(struct rt2x00_dev *rt2x00dev,
+				   unsigned int channel, short txpower)
 {
 	if (rt2x00_rt(rt2x00dev, RT3593) ||
 	    rt2x00_rt(rt2x00dev, RT3883))
 		txpower = rt2x00_get_field8(txpower, EEPROM_TXPOWER_ALC);
 
 	if (channel <= 14)
-		return clamp_t(char, txpower, MIN_G_TXPOWER, MAX_G_TXPOWER);
+		return clamp_t(short, txpower, MIN_G_TXPOWER, MAX_G_TXPOWER);
 
 	if (rt2x00_rt(rt2x00dev, RT3593) ||
 	    rt2x00_rt(rt2x00dev, RT3883))
-		return clamp_t(char, txpower, MIN_A_TXPOWER_3593,
+		return clamp_t(short, txpower, MIN_A_TXPOWER_3593,
 			       MAX_A_TXPOWER_3593);
 	else
-		return clamp_t(char, txpower, MIN_A_TXPOWER, MAX_A_TXPOWER);
+		return clamp_t(short, txpower, MIN_A_TXPOWER, MAX_A_TXPOWER);
 }
 
 static void rt3883_bbp_adjust(struct rt2x00_dev *rt2x00dev,
-- 
2.35.1


-- 
With Best Regards,
Andy Shevchenko