sravan/system76-embedded-controller
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Move i2c support to common

Browse Source
This commit is contained in:
Jeremy Soller
2019-11-13 14:33:04 -07:00
parent 894e448dfc
commit 890d8e9968
9 changed files with 215 additions and 152 deletions
Download Patch File Download Diff File Expand all files Collapse all files

94
src/arch/avr/i2c.c
View File

@ -2,15 +2,12 @@
#include <avr/io.h>
#include <util/twi.h>
#include <arch/i2c.h>
#include <board/cpu.h>
#include <common/i2c.h>
#define TIMEOUT (F_CPU/1000)
#define I2C_READ 0x01
#define I2C_WRITE 0x00
uint8_t i2c_start(uint8_t addr, uint8_t rw) {
uint8_t i2c_start(uint8_t addr, bool read) {
uint32_t count;
// reset TWI control register
@ -32,7 +29,7 @@ uint8_t i2c_start(uint8_t addr, uint8_t rw) {
}
// load slave addr into data register
TWDR = ((addr << 1) | rw);
TWDR = ((addr << 1) | read);
// start transmission of addr
TWCR = (1<<TWINT) | (1<<TWEN);
// wait for end of transmission
@ -53,7 +50,7 @@ uint8_t i2c_start(uint8_t addr, uint8_t rw) {
return 0;
}
void i2c_stop() {
void i2c_stop(void) {
// transmit STOP condition
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWSTO);
}
@ -81,83 +78,16 @@ uint8_t i2c_write(uint8_t data) {
return 0;
}
uint8_t i2c_read_ack() {
// start TWI module and acknowledge data after reception
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
uint8_t i2c_read(bool ack) {
if (ack) {
// start TWI module and acknowledge data after reception
TWCR = (1<<TWINT) | (1<<TWEN) | (1<<TWEA);
} else {
// start receiving without acknowledging reception
TWCR = (1<<TWINT) | (1<<TWEN);
}
// wait for end of transmission
while( !(TWCR & (1<<TWINT)) );
// return received data from TWDR
return TWDR;
}
uint8_t i2c_read_nack() {
// start receiving without acknowledging reception
TWCR = (1<<TWINT) | (1<<TWEN);
// wait for end of transmission
while( !(TWCR & (1<<TWINT)) );
// return received data from TWDR
return TWDR;
}
uint8_t i2c_recv(uint8_t addr, uint8_t* data, uint16_t length) {
if (i2c_start(addr, I2C_READ)) return 1;
uint16_t i;
for (i = 0; i < (length-1); i++)
{
data[i] = i2c_read_ack();
}
data[(length-1)] = i2c_read_nack();
i2c_stop();
return 0;
}
uint8_t i2c_send(uint8_t addr, uint8_t* data, uint16_t length) {
if (i2c_start(addr, I2C_WRITE)) return 1;
uint16_t i;
for (i = 0; i < length; i++) {
if (i2c_write(data[i])) return 1;
}
i2c_stop();
return 0;
}
uint8_t i2c_get(uint8_t addr, uint8_t reg, uint8_t* data, uint16_t length) {
if (i2c_start(addr, I2C_WRITE)) return 1;
if (i2c_write(reg)) return 1;
if (i2c_start(addr, I2C_READ)) return 1;
uint16_t i;
for (i = 0; i < (length-1); i++)
{
data[i] = i2c_read_ack();
}
data[(length-1)] = i2c_read_nack();
i2c_stop();
return 0;
}
uint8_t i2c_set(uint8_t addr, uint8_t reg, uint8_t* data, uint16_t length) {
if (i2c_start(addr, I2C_WRITE)) return 1;
if(i2c_write(reg)) return 1;
uint16_t i;
for (i = 0; i < length; i++)
{
if (i2c_write(data[i])) return 1;
}
i2c_stop();
return 0;
}