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/* SPDX-License-Identifier: GPL-2.0-only OR MIT */
#include <console/console.h>
#include <device/i2c_simple.h>
#include <soc/mt6691.h>
#define MT6691_MIN_VOLTAGE 300000
#define MT6691_MAX_VOLTAGE 1300000
#define MT6691_STEP_UV 5000
enum {
MT6691_SLAVE_ADDR = 0x51,
};
int mt6691_set_voltage(uint8_t i2c_num, unsigned int volt_uv)
{
uint8_t selector;
if (volt_uv > MT6691_MAX_VOLTAGE || volt_uv < MT6691_MIN_VOLTAGE) {
printk(BIOS_ERR, "%s: voltage out of range\n", __func__);
return -1;
}
selector = DIV_ROUND_UP(volt_uv - MT6691_MIN_VOLTAGE, MT6691_STEP_UV);
return i2c_write_field(i2c_num, MT6691_SLAVE_ADDR,
MT6691_VSEL0, selector, 0xFF, 0);
}
int mt6691_get_voltage(uint8_t i2c_num)
{
uint8_t selector = 0;
unsigned int volt;
if (i2c_read_field(i2c_num, MT6691_SLAVE_ADDR, MT6691_VSEL0,
&selector, 0xFF, 0) < 0) {
printk(BIOS_ERR, "%s: failed to get voltage from i2c\n", __func__);
return -1;
}
volt = (selector * MT6691_STEP_UV) + MT6691_MIN_VOLTAGE;
if (volt > MT6691_MAX_VOLTAGE) {
printk(BIOS_ERR, "%s: voltage out of range\n", __func__);
return -1;
}
return volt;
}
static uint8_t get_mt6691_chip_id(uint8_t i2c_num)
{
uint8_t id;
if (i2c_read_field(i2c_num, MT6691_SLAVE_ADDR, MT6691_MONITOR,
&id, 0x1, MT6691_PGOOD_SHIFT) < 0) {
printk(BIOS_ERR, "%s: failed to read from i2c", __func__);
return 0;
}
return id;
}
void mt6691_probe(uint8_t i2c_num)
{
/* Check device ID is MT6691 */
if (!get_mt6691_chip_id(i2c_num)) {
printk(BIOS_ERR, "unknown MT6691 chip_id\n");
return;
}
/* Slew rate 12mV */
i2c_write_field(i2c_num, MT6691_SLAVE_ADDR, MT6691_CTRL2, 0x1,
MT6691_DN_SR_MASK, MT6691_DN_SR_SHIFT);
}
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