xref: /aosp_15_r20/external/coreboot/src/soc/mediatek/mt8195/mt6691.c (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only OR MIT */
2 
3 #include <console/console.h>
4 #include <device/i2c_simple.h>
5 #include <soc/mt6691.h>
6 
7 #define MT6691_MIN_VOLTAGE		300000
8 #define MT6691_MAX_VOLTAGE		1300000
9 #define MT6691_STEP_UV			5000
10 
11 enum {
12 	MT6691_SLAVE_ADDR = 0x51,
13 };
14 
mt6691_set_voltage(uint8_t i2c_num,unsigned int volt_uv)15 int mt6691_set_voltage(uint8_t i2c_num, unsigned int volt_uv)
16 {
17 	uint8_t selector;
18 
19 	if (volt_uv > MT6691_MAX_VOLTAGE || volt_uv < MT6691_MIN_VOLTAGE) {
20 		printk(BIOS_ERR, "%s: voltage out of range\n", __func__);
21 		return -1;
22 	}
23 
24 	selector = DIV_ROUND_UP(volt_uv - MT6691_MIN_VOLTAGE, MT6691_STEP_UV);
25 
26 	return i2c_write_field(i2c_num, MT6691_SLAVE_ADDR,
27 			       MT6691_VSEL0, selector, 0xFF, 0);
28 }
29 
mt6691_get_voltage(uint8_t i2c_num)30 int mt6691_get_voltage(uint8_t i2c_num)
31 {
32 	uint8_t selector = 0;
33 	unsigned int volt;
34 
35 	if (i2c_read_field(i2c_num, MT6691_SLAVE_ADDR, MT6691_VSEL0,
36 			   &selector, 0xFF, 0) < 0) {
37 		printk(BIOS_ERR, "%s: failed to get voltage from i2c\n", __func__);
38 		return -1;
39 	}
40 
41 	volt = (selector * MT6691_STEP_UV) + MT6691_MIN_VOLTAGE;
42 
43 	if (volt > MT6691_MAX_VOLTAGE) {
44 		printk(BIOS_ERR, "%s: voltage out of range\n", __func__);
45 		return -1;
46 	}
47 
48 	return volt;
49 }
50 
get_mt6691_chip_id(uint8_t i2c_num)51 static uint8_t get_mt6691_chip_id(uint8_t i2c_num)
52 {
53 	uint8_t id;
54 
55 	if (i2c_read_field(i2c_num, MT6691_SLAVE_ADDR, MT6691_MONITOR,
56 			   &id, 0x1, MT6691_PGOOD_SHIFT) < 0) {
57 		printk(BIOS_ERR, "%s: failed to read from i2c", __func__);
58 		return 0;
59 	}
60 
61 	return id;
62 }
63 
mt6691_probe(uint8_t i2c_num)64 void mt6691_probe(uint8_t i2c_num)
65 {
66 	/* Check device ID is MT6691 */
67 	if (!get_mt6691_chip_id(i2c_num)) {
68 		printk(BIOS_ERR, "unknown MT6691 chip_id\n");
69 		return;
70 	}
71 	/* Slew rate 12mV */
72 	i2c_write_field(i2c_num, MT6691_SLAVE_ADDR, MT6691_CTRL2, 0x1,
73 			MT6691_DN_SR_MASK, MT6691_DN_SR_SHIFT);
74 }
75