aspeed/i2c: Handle receive command in separate function

Receive command handling may have to be deferred if a previous receive
done interrupt was not yet acknowledged. Move receive command handling
into a separate function to prepare for the necessary changes.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20180914063506.20815-3-clg@kaod.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Guenter Roeck 2018-09-25 14:02:31 +01:00 committed by Peter Maydell
parent 5540cb97f7
commit 7bd9c60d4e

View File

@ -187,6 +187,26 @@ static uint8_t aspeed_i2c_get_state(AspeedI2CBus *bus)
return (bus->cmd >> I2CD_TX_STATE_SHIFT) & I2CD_TX_STATE_MASK;
}
static void aspeed_i2c_handle_rx_cmd(AspeedI2CBus *bus)
{
int ret;
aspeed_i2c_set_state(bus, I2CD_MRXD);
ret = i2c_recv(bus->bus);
if (ret < 0) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: read failed\n", __func__);
ret = 0xff;
} else {
bus->intr_status |= I2CD_INTR_RX_DONE;
}
bus->buf = (ret & I2CD_BYTE_BUF_RX_MASK) << I2CD_BYTE_BUF_RX_SHIFT;
if (bus->cmd & I2CD_M_S_RX_CMD_LAST) {
i2c_nack(bus->bus);
}
bus->cmd &= ~(I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST);
aspeed_i2c_set_state(bus, I2CD_MACTIVE);
}
/*
* The state machine needs some refinement. It is only used to track
* invalid STOP commands for the moment.
@ -233,22 +253,7 @@ static void aspeed_i2c_bus_handle_cmd(AspeedI2CBus *bus, uint64_t value)
}
if (bus->cmd & (I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST)) {
int ret;
aspeed_i2c_set_state(bus, I2CD_MRXD);
ret = i2c_recv(bus->bus);
if (ret < 0) {
qemu_log_mask(LOG_GUEST_ERROR, "%s: read failed\n", __func__);
ret = 0xff;
} else {
bus->intr_status |= I2CD_INTR_RX_DONE;
}
bus->buf = (ret & I2CD_BYTE_BUF_RX_MASK) << I2CD_BYTE_BUF_RX_SHIFT;
if (bus->cmd & I2CD_M_S_RX_CMD_LAST) {
i2c_nack(bus->bus);
}
bus->cmd &= ~(I2CD_M_RX_CMD | I2CD_M_S_RX_CMD_LAST);
aspeed_i2c_set_state(bus, I2CD_MACTIVE);
aspeed_i2c_handle_rx_cmd(bus);
}
if (bus->cmd & I2CD_M_STOP_CMD) {