[U-Boot] [PATCH 01/17] sunxi: axp221: Protect axp221_init against multiple calls

[Hans de Goede]

The voltage setting code knows it needs to call axp221_init before calling
the various voltage setting functions.

But users of axp utility functions like axp221_get_sid() do not know this,
so the utility functions always call axp221_init() to ensure that the
p2wi / rsb setup magic has been done.

Since doing this repeatedly is quite expensive, add a check to axp221_init
so that it only does the initialization once.

Signed-off-by: Hans de Goede <hdegoede at redhat.com>
---
 drivers/power/axp221.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/power/axp221.c b/drivers/power/axp221.c
index 1fda19a..728727b 100644
--- a/drivers/power/axp221.c
+++ b/drivers/power/axp221.c
@@ -304,9 +304,14 @@ int axp221_set_aldo3(unsigned int mvolt)
 
 int axp221_init(void)
 {
+	/* This cannot be 0 because it is used in SPL before BSS is ready */
+	static int needs_init = 1;
 	u8 axp_chip_id;
 	int ret;
 
+	if (!needs_init)
+		return 0;
+
 	ret = pmic_bus_init();
 	if (ret)
 		return ret;
@@ -318,6 +323,7 @@ int axp221_init(void)
 	if (!(axp_chip_id == 0x6 || axp_chip_id == 0x7 || axp_chip_id == 0x17))
 		return -ENODEV;
 
+	needs_init = 0;
 	return 0;
 }
 
-- 
2.1.0