sunxi: axp209: fix incorrect limits on ldo3

PATCH New Iain Paton 2 participants 2 messages Mar 25, 2015 – Mar 26, 2015 X-powers multifunction PMIC device drivers

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Iain Paton

author

2015-03-25 16:03 UTC #0 lore raw

PATCH 1/1 sunxi: axp209: fix incorrect limits on ldo3

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 <[email protected]>

---
 drivers/power/axp209.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

drivers/power/axp209.c +1 -1

index 4565398..f8c9b77 100644
@@ -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);
 }

Signature · 1 line

2.1.3

Hans de Goede

2015-03-26 12:26 UTC #1 lore raw

PATCH 1/1 sunxi: axp209: fix incorrect limits on ldo3

Hi,

Quoted 9 lines · Iain Paton

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

Quoted 4 lines

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 <[email protected]>

Thanks, I've merged this into u-boot-sunxi/master and added this in a small fixed pull-req which I've just send.

Regards,

Hans

Quoted 18 lines

---
  drivers/power/axp209.c | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

drivers/power/axp209.c +1 -1

index 4565398..f8c9b77 100644
@@ -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);
  }