diff --git a/drivers/i2c/busses/i2c-imx.c b/drivers/i2c/busses/i2c-imx.c index ca47e4041ca5..b80fdc1f0092 100644 --- a/drivers/i2c/busses/i2c-imx.c +++ b/drivers/i2c/busses/i2c-imx.c @@ -209,6 +209,7 @@ struct imx_i2c_struct { struct imx_i2c_dma *dma; struct i2c_client *slave; + enum i2c_slave_event last_slave_event; }; static const struct imx_i2c_hwdata imx1_i2c_hwdata = { @@ -675,6 +676,36 @@ static void i2c_imx_enable_bus_idle(struct imx_i2c_struct *i2c_imx) } } +static void i2c_imx_slave_event(struct imx_i2c_struct *i2c_imx, + enum i2c_slave_event event, u8 *val) +{ + i2c_slave_event(i2c_imx->slave, event, val); + i2c_imx->last_slave_event = event; +} + +static void i2c_imx_slave_finish_op(struct imx_i2c_struct *i2c_imx) +{ + u8 val; + + while (i2c_imx->last_slave_event != I2C_SLAVE_STOP) { + switch (i2c_imx->last_slave_event) { + case I2C_SLAVE_READ_REQUESTED: + i2c_imx_slave_event(i2c_imx, I2C_SLAVE_READ_PROCESSED, + &val); + break; + + case I2C_SLAVE_WRITE_REQUESTED: + case I2C_SLAVE_READ_PROCESSED: + case I2C_SLAVE_WRITE_RECEIVED: + i2c_imx_slave_event(i2c_imx, I2C_SLAVE_STOP, &val); + break; + + case I2C_SLAVE_STOP: + break; + } + } +} + static irqreturn_t i2c_imx_slave_isr(struct imx_i2c_struct *i2c_imx, unsigned int status, unsigned int ctl) { @@ -687,9 +718,11 @@ static irqreturn_t i2c_imx_slave_isr(struct imx_i2c_struct *i2c_imx, } if (status & I2SR_IAAS) { /* Addressed as a slave */ + i2c_imx_slave_finish_op(i2c_imx); if (status & I2SR_SRW) { /* Master wants to read from us*/ dev_dbg(&i2c_imx->adapter.dev, "read requested"); - i2c_slave_event(i2c_imx->slave, I2C_SLAVE_READ_REQUESTED, &value); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_READ_REQUESTED, &value); /* Slave transmit */ ctl |= I2CR_MTX; @@ -699,7 +732,8 @@ static irqreturn_t i2c_imx_slave_isr(struct imx_i2c_struct *i2c_imx, imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR); } else { /* Master wants to write to us */ dev_dbg(&i2c_imx->adapter.dev, "write requested"); - i2c_slave_event(i2c_imx->slave, I2C_SLAVE_WRITE_REQUESTED, &value); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_WRITE_REQUESTED, &value); /* Slave receive */ ctl &= ~I2CR_MTX; @@ -710,17 +744,20 @@ static irqreturn_t i2c_imx_slave_isr(struct imx_i2c_struct *i2c_imx, } else if (!(ctl & I2CR_MTX)) { /* Receive mode */ if (status & I2SR_IBB) { /* No STOP signal detected */ value = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2DR); - i2c_slave_event(i2c_imx->slave, I2C_SLAVE_WRITE_RECEIVED, &value); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_WRITE_RECEIVED, &value); } else { /* STOP signal is detected */ dev_dbg(&i2c_imx->adapter.dev, "STOP signal detected"); - i2c_slave_event(i2c_imx->slave, I2C_SLAVE_STOP, &value); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_STOP, &value); } } else if (!(status & I2SR_RXAK)) { /* Transmit mode received ACK */ ctl |= I2CR_MTX; imx_i2c_write_reg(ctl, i2c_imx, IMX_I2C_I2CR); - i2c_slave_event(i2c_imx->slave, I2C_SLAVE_READ_PROCESSED, &value); + i2c_imx_slave_event(i2c_imx, + I2C_SLAVE_READ_PROCESSED, &value); imx_i2c_write_reg(value, i2c_imx, IMX_I2C_I2DR); } else { /* Transmit mode received NAK */ @@ -761,6 +798,7 @@ static int i2c_imx_reg_slave(struct i2c_client *client) return -EBUSY; i2c_imx->slave = client; + i2c_imx->last_slave_event = I2C_SLAVE_STOP; /* Resume */ ret = pm_runtime_get_sync(i2c_imx->adapter.dev.parent); @@ -813,10 +851,17 @@ static irqreturn_t i2c_imx_isr(int irq, void *dev_id) status = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2SR); ctl = imx_i2c_read_reg(i2c_imx, IMX_I2C_I2CR); + if (status & I2SR_IIF) { i2c_imx_clear_irq(i2c_imx, I2SR_IIF); - if (i2c_imx->slave && !(ctl & I2CR_MSTA)) - return i2c_imx_slave_isr(i2c_imx, status, ctl); + if (i2c_imx->slave) { + if (!(ctl & I2CR_MSTA)) { + return i2c_imx_slave_isr(i2c_imx, status, ctl); + } else if (i2c_imx->last_slave_event != + I2C_SLAVE_STOP) { + i2c_imx_slave_finish_op(i2c_imx); + } + } return i2c_imx_master_isr(i2c_imx, status); }