Commit 7bd9c60d authored by Guenter Roeck's avatar Guenter Roeck Committed by Peter Maydell
Browse files

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: default avatarGuenter Roeck <linux@roeck-us.net>
Signed-off-by: default avatarCédric Le Goater <clg@kaod.org>
Message-id: 20180914063506.20815-3-clg@kaod.org
Reviewed-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
parent 5540cb97

hw/i2c/aspeed_i2c.c

+21 −16
Original line number Diff line number Diff line
@@ -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) {