[U-Boot] [PATCH] sunxi: axp209: fix incorrect limits on ldo3

Iain Paton ipaton0 at gmail.com
Wed Mar 25 17:03:26 CET 2015


board/sunxi/board.c tries to set ldo3 to 2.8v however drivers/power/axp209.c
contains an incorrect limit on ldo3 of 2.275v

The origin of the incorrect limit seems likely due to some inconsistencies
in the axp209 datasheet. ldo3 is described with different limits in 
different sections. register 0x29 uses 7 bits for voltage configuration
while the 2.275v limit would apply if only 6 bits were used.
Probably this is a cut&paste error from register 0x23

The linux kernel driver has the correct limit and operation up to the 2.8v
required by my board has been physically verified with a multimeter.

Signed-off-by: Iain Paton <ipaton0 at gmail.com>
---
 drivers/power/axp209.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/power/axp209.c b/drivers/power/axp209.c
index 4565398..f8c9b77 100644
--- a/drivers/power/axp209.c
+++ b/drivers/power/axp209.c
@@ -119,7 +119,7 @@ int axp209_set_ldo3(int mvolt)
 	if (mvolt == -1)
 		cfg = 0x80;	/* determined by LDO3IN pin */
 	else
-		cfg = axp209_mvolt_to_cfg(mvolt, 700, 2275, 25);
+		cfg = axp209_mvolt_to_cfg(mvolt, 700, 3500, 25);
 
 	return axp209_write(AXP209_LDO3_VOLTAGE, cfg);
 }
-- 
2.1.3



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