xref: /openbmc/u-boot/drivers/power/axp152.c (revision b2e02d28)
1 /*
2  * (C) Copyright 2012
3  * Henrik Nordstrom <henrik@henriknordstrom.net>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 #include <common.h>
8 #include <i2c.h>
9 #include <axp152.h>
10 
11 enum axp152_reg {
12 	AXP152_CHIP_VERSION = 0x3,
13 	AXP152_DCDC2_VOLTAGE = 0x23,
14 	AXP152_DCDC3_VOLTAGE = 0x27,
15 	AXP152_DCDC4_VOLTAGE = 0x2B,
16 	AXP152_LDO2_VOLTAGE = 0x2A,
17 	AXP152_SHUTDOWN = 0x32,
18 };
19 
20 #define AXP152_POWEROFF			(1 << 7)
21 
22 static int axp152_write(enum axp152_reg reg, u8 val)
23 {
24 	return i2c_write(0x30, reg, 1, &val, 1);
25 }
26 
27 static int axp152_read(enum axp152_reg reg, u8 *val)
28 {
29 	return i2c_read(0x30, reg, 1, val, 1);
30 }
31 
32 static u8 axp152_mvolt_to_target(int mvolt, int min, int max, int div)
33 {
34 	if (mvolt < min)
35 		mvolt = min;
36 	else if (mvolt > max)
37 		mvolt = max;
38 
39 	return (mvolt - min) / div;
40 }
41 
42 int axp152_set_dcdc2(int mvolt)
43 {
44 	int rc;
45 	u8 current, target;
46 
47 	target = axp152_mvolt_to_target(mvolt, 700, 2275, 25);
48 
49 	/* Do we really need to be this gentle? It has built-in voltage slope */
50 	while ((rc = axp152_read(AXP152_DCDC2_VOLTAGE, &current)) == 0 &&
51 	       current != target) {
52 		if (current < target)
53 			current++;
54 		else
55 			current--;
56 		rc = axp152_write(AXP152_DCDC2_VOLTAGE, current);
57 		if (rc)
58 			break;
59 	}
60 	return rc;
61 }
62 
63 int axp152_set_dcdc3(int mvolt)
64 {
65 	u8 target = axp152_mvolt_to_target(mvolt, 700, 3500, 50);
66 
67 	return axp152_write(AXP152_DCDC3_VOLTAGE, target);
68 }
69 
70 int axp152_set_dcdc4(int mvolt)
71 {
72 	u8 target = axp152_mvolt_to_target(mvolt, 700, 3500, 25);
73 
74 	return axp152_write(AXP152_DCDC4_VOLTAGE, target);
75 }
76 
77 int axp152_set_ldo2(int mvolt)
78 {
79 	u8 target = axp152_mvolt_to_target(mvolt, 700, 3500, 100);
80 
81 	return axp152_write(AXP152_LDO2_VOLTAGE, target);
82 }
83 
84 int axp152_init(void)
85 {
86 	u8 ver;
87 	int rc;
88 
89 	rc = axp152_read(AXP152_CHIP_VERSION, &ver);
90 	if (rc)
91 		return rc;
92 
93 	if (ver != 0x05)
94 		return -1;
95 
96 	return 0;
97 }
98