xref: /aosp_15_r20/external/coreboot/src/device/i2c.c (revision b9411a12aaaa7e1e6a6fb7c5e057f44ee179a49c)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 
3 #include <device/i2c_simple.h>
4 #include <stdint.h>
5 
i2c_read_field(unsigned int bus,uint8_t chip,uint8_t reg,uint8_t * data,uint8_t mask,uint8_t shift)6 int i2c_read_field(unsigned int bus, uint8_t chip, uint8_t reg, uint8_t *data,
7 		   uint8_t mask, uint8_t shift)
8 {
9 	int ret;
10 	uint8_t buf = 0;
11 
12 	ret = i2c_readb(bus, chip, reg, &buf);
13 
14 	buf &= (mask << shift);
15 	*data = (buf >> shift);
16 
17 	return ret;
18 }
19 
i2c_write_field(unsigned int bus,uint8_t chip,uint8_t reg,uint8_t data,uint8_t mask,uint8_t shift)20 int i2c_write_field(unsigned int bus, uint8_t chip, uint8_t reg, uint8_t data,
21 		    uint8_t mask, uint8_t shift)
22 {
23 	int ret;
24 	uint8_t buf = 0;
25 
26 	ret = i2c_readb(bus, chip, reg, &buf);
27 
28 	buf &= ~(mask << shift);
29 	buf |= (data << shift);
30 
31 	ret |= i2c_writeb(bus, chip, reg, buf);
32 
33 	return ret;
34 }
35