claunia/86Box
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

I2C overhaul part 6: making DDC actually work

Browse Source
This commit is contained in:
RichardG867
2020-11-24 01:56:06 -03:00
parent d6b1d2c63a
commit 315e3e8d11
5 changed files with 177 additions and 130 deletions
Download Patch File Download Diff File Expand all files Collapse all files

32
src/device/i2c_gpio.c
View File

@@ -55,7 +55,7 @@ enum {
typedef struct {
char *bus_name;
void *i2c;
uint8_t scl, sda, state, slave_state, slave_addr,
uint8_t scl, sda, receive_wait_sda, state, slave_state, slave_addr,
slave_read, last_sda, pos, transmit, byte;
} i2c_gpio_t;
@@ -188,11 +188,12 @@ i2c_gpio_set(void *dev_handle, uint8_t scl, uint8_t sda)
{
i2c_gpio_t *dev = (i2c_gpio_t *) dev_handle;
i2c_gpio_log(3, "I2C GPIO %s: scl=%d->%d sda=%d->%d last_valid_sda=%d state=%d\n", dev->bus_name, dev->scl, scl, dev->last_sda, sda, dev->sda, dev->state);
switch (dev->state) {
case I2C_IDLE:
/* dev->scl check breaks NCR SDMS. */
if (scl && dev->last_sda && !sda) { /* start bit */
i2c_gpio_log(2, "I2C GPIO %s: Start bit received (from IDLE)\n", dev->bus_name);
if (scl && dev->last_sda && !sda) { /* start condition; dev->scl check breaks NCR SDMS */
i2c_gpio_log(2, "I2C GPIO %s: Start condition received (from IDLE)\n", dev->bus_name);
dev->state = I2C_RECEIVE;
dev->pos = 0;
}
@@ -201,6 +202,8 @@ i2c_gpio_set(void *dev_handle, uint8_t scl, uint8_t sda)
case I2C_RECEIVE_WAIT:
if (!dev->scl && scl)
dev->state = I2C_RECEIVE;
else if (!dev->scl && !scl && dev->last_sda && sda) /* workaround for repeated start condition on Windows XP DDC */
dev->receive_wait_sda = 1;
/* fall-through */
case I2C_RECEIVE:
@@ -213,12 +216,12 @@ i2c_gpio_set(void *dev_handle, uint8_t scl, uint8_t sda)
if (++dev->pos == 8)
dev->state = i2c_gpio_write(dev);
} else if (dev->scl && scl) {
if (sda && !dev->last_sda) { /* stop bit */
i2c_gpio_log(2, "I2C GPIO %s: Stop bit received (from RECEIVE)\n", dev->bus_name);
if (sda && !dev->last_sda) { /* stop condition */
i2c_gpio_log(2, "I2C GPIO %s: Stop condition received (from RECEIVE)\n", dev->bus_name);
dev->state = I2C_IDLE;
i2c_gpio_stop(dev);
} else if (!sda && dev->last_sda) { /* start bit */
i2c_gpio_log(2, "I2C GPIO %s: Start bit received (from RECEIVE)\n", dev->bus_name);
} else if (!sda && dev->last_sda) { /* start condition */
i2c_gpio_log(2, "I2C GPIO %s: Start condition received (from RECEIVE)\n", dev->bus_name);
dev->pos = 0;
dev->slave_state = SLAVE_IDLE;
}
@@ -229,6 +232,7 @@ i2c_gpio_set(void *dev_handle, uint8_t scl, uint8_t sda)
if (!dev->scl && scl) {
i2c_gpio_log(2, "I2C GPIO %s: Acknowledging transfer to %02X\n", dev->bus_name, dev->slave_addr);
sda = 0;
dev->receive_wait_sda = 0; /* ack */
dev->pos = 0;
dev->state = (dev->transmit == TRANSMITTER_MASTER) ? I2C_RECEIVE_WAIT : I2C_TRANSMIT;
}
@@ -261,13 +265,13 @@ i2c_gpio_set(void *dev_handle, uint8_t scl, uint8_t sda)
case I2C_TRANSMIT_WAIT:
if (dev->scl && scl) {
if (dev->last_sda && !sda) { /* start bit */
if (dev->last_sda && !sda) { /* start condition */
i2c_gpio_next_byte(dev);
dev->pos = 0;
i2c_gpio_log(2, "I2C GPIO %s: Next byte = %02X\n", dev->bus_name, dev->byte);
}
if (!dev->last_sda && sda) { /* stop bit */
i2c_gpio_log(2, "I2C GPIO %s: Stop bit received (from TRANSMIT_WAIT)\n", dev->bus_name);
if (!dev->last_sda && sda) { /* stop condition */
i2c_gpio_log(2, "I2C GPIO %s: Stop condition received (from TRANSMIT_WAIT)\n", dev->bus_name);
dev->state = I2C_IDLE;
i2c_gpio_stop(dev);
}
@@ -277,8 +281,8 @@ i2c_gpio_set(void *dev_handle, uint8_t scl, uint8_t sda)
case I2C_TRANSMIT_START:
if (!dev->scl && scl)
dev->state = I2C_TRANSMIT;
if (dev->scl && scl && !dev->last_sda && sda) { /* stop bit */
i2c_gpio_log(2, "I2C GPIO %s: Stop bit received (from TRANSMIT_START)\n", dev->bus_name);
if (dev->scl && scl && !dev->last_sda && sda) { /* stop condition */
i2c_gpio_log(2, "I2C GPIO %s: Stop condition received (from TRANSMIT_START)\n", dev->bus_name);
dev->state = I2C_IDLE;
i2c_gpio_stop(dev);
}
@@ -327,7 +331,7 @@ i2c_gpio_get_sda(void *dev_handle)
return dev->sda;
case I2C_RECEIVE_WAIT:
return 0; /* ack */
return dev->receive_wait_sda;
default:
return 1;