| Message ID | 20180723174808.4007-1-jae.hyun.yoo@linux.intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [i2c-next] i2c: aspeed: Handle master/slave combined irq events properly | expand |
On 07/23/2018 10:48 AM, Jae Hyun Yoo wrote: > In most of cases, interrupt bits are set one by one but there are > also a lot of other cases that Aspeed I2C IP sends multiple > interrupt bits with combining master and slave events using a > single interrupt call. It happens much in multi-master environment much more > than single-master. For an example, when master is waiting for a > NORMAL_STOP interrupt in its MASTER_STOP state, SLAVE_MATCH and > RX_DONE interrupts could come along with the NORMAL_STOP in case of > an another master immediately sends data just after acquiring the > bus. In this case, the NORMAL_STOP interrupt should be handled > by master_irq and the SLAVE_MATCH and RX_DONE interrupts should be > handled by slave_irq. This commit modifies irq hadling logic to > handle the master/slave combined events properly. > > Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> > --- > drivers/i2c/busses/i2c-aspeed.c | 137 ++++++++++++++++++-------------- > 1 file changed, 76 insertions(+), 61 deletions(-) > > diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c > index efb89422d496..24d43f143a55 100644 > --- a/drivers/i2c/busses/i2c-aspeed.c > +++ b/drivers/i2c/busses/i2c-aspeed.c > @@ -82,6 +82,11 @@ > #define ASPEED_I2CD_INTR_RX_DONE BIT(2) > #define ASPEED_I2CD_INTR_TX_NAK BIT(1) > #define ASPEED_I2CD_INTR_TX_ACK BIT(0) > +#define ASPEED_I2CD_INTR_ERRORS \ > + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ > + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ > + ASPEED_I2CD_INTR_ABNORMAL | \ > + ASPEED_I2CD_INTR_ARBIT_LOSS) > #define ASPEED_I2CD_INTR_ALL \ > (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ > ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \ > @@ -150,6 +155,7 @@ struct aspeed_i2c_bus { > int cmd_err; > /* Protected only by i2c_lock_bus */ > int master_xfer_result; > + u32 irq_status; > #if IS_ENABLED(CONFIG_I2C_SLAVE) > struct i2c_client *slave; > enum aspeed_i2c_slave_state slave_state; > @@ -229,36 +235,30 @@ static int aspeed_i2c_recover_bus(struct aspeed_i2c_bus *bus) > #if IS_ENABLED(CONFIG_I2C_SLAVE) > static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) > { > - u32 command, irq_status, status_ack = 0; > + u32 command, status_ack = 0; > struct i2c_client *slave = bus->slave; > - bool irq_handled = true; > u8 value; > > - if (!slave) { > - irq_handled = false; > - goto out; > - } > + if (!slave) > + return false; > > command = readl(bus->base + ASPEED_I2C_CMD_REG); > - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); > > /* Slave was requested, restart state machine. */ > - if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { > + if (bus->irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { > status_ack |= ASPEED_I2CD_INTR_SLAVE_MATCH; > bus->slave_state = ASPEED_I2C_SLAVE_START; > } > > /* Slave is not currently active, irq was for someone else. */ > - if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) { > - irq_handled = false; > - goto out; > - } > + if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) > + return false; > > dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n", > - irq_status, command); > + bus->irq_status, command); > > /* Slave was sent something. */ > - if (irq_status & ASPEED_I2CD_INTR_RX_DONE) { > + if (bus->irq_status & ASPEED_I2CD_INTR_RX_DONE) { > value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; > /* Handle address frame. */ > if (bus->slave_state == ASPEED_I2C_SLAVE_START) { > @@ -273,28 +273,29 @@ static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) > } > > /* Slave was asked to stop. */ > - if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { > + if (bus->irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { > status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP; > bus->slave_state = ASPEED_I2C_SLAVE_STOP; > } > - if (irq_status & ASPEED_I2CD_INTR_TX_NAK) { > + if (bus->irq_status & ASPEED_I2CD_INTR_TX_NAK) { > status_ack |= ASPEED_I2CD_INTR_TX_NAK; > bus->slave_state = ASPEED_I2C_SLAVE_STOP; > } > + if (bus->irq_status & ASPEED_I2CD_INTR_TX_ACK) { > + status_ack |= ASPEED_I2CD_INTR_TX_ACK; > + } > > switch (bus->slave_state) { > case ASPEED_I2C_SLAVE_READ_REQUESTED: > - if (irq_status & ASPEED_I2CD_INTR_TX_ACK) > + if (bus->irq_status & ASPEED_I2CD_INTR_TX_ACK) > dev_err(bus->dev, "Unexpected ACK on read request.\n"); > bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED; > - > i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); > writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); > writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); > break; > case ASPEED_I2C_SLAVE_READ_PROCESSED: > - status_ack |= ASPEED_I2CD_INTR_TX_ACK; > - if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK)) > + if (!(bus->irq_status & ASPEED_I2CD_INTR_TX_ACK)) > dev_err(bus->dev, > "Expected ACK after processed read.\n"); > i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); > @@ -317,14 +318,8 @@ static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) > break; > } > > - if (status_ack != irq_status) > - dev_err(bus->dev, > - "irq handled != irq. expected %x, but was %x\n", > - irq_status, status_ack); > - writel(status_ack, bus->base + ASPEED_I2C_INTR_STS_REG); > - > -out: > - return irq_handled; > + bus->irq_status ^= status_ack; > + return !bus->irq_status; > } > #endif /* CONFIG_I2C_SLAVE */ > > @@ -382,19 +377,19 @@ static int aspeed_i2c_is_irq_error(u32 irq_status) > > static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > { > - u32 irq_status, status_ack = 0, command = 0; > + u32 status_ack = 0, command = 0; > struct i2c_msg *msg; > u8 recv_byte; > int ret; > > - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); > - /* Ack all interrupt bits. */ > - writel(irq_status, bus->base + ASPEED_I2C_INTR_STS_REG); > - > - if (irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { > + if (bus->irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { > bus->master_state = ASPEED_I2C_MASTER_INACTIVE; > status_ack |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE; > goto out_complete; > + } else { > + /* Master is not currently active, irq was for someone else. */ > + if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE) > + goto out_no_complete; > } > > /* > @@ -402,20 +397,23 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > * should clear the command queue effectively taking us back to the > * INACTIVE state. > */ > - ret = aspeed_i2c_is_irq_error(irq_status); > - if (ret < 0) { > + ret = aspeed_i2c_is_irq_error(bus->irq_status); > + if (ret) { > dev_dbg(bus->dev, "received error interrupt: 0x%08x\n", > - irq_status); > + bus->irq_status); > bus->cmd_err = ret; > bus->master_state = ASPEED_I2C_MASTER_INACTIVE; > + status_ack |= (bus->irq_status & ASPEED_I2CD_INTR_ERRORS); > goto out_complete; > } > > /* We are in an invalid state; reset bus to a known state. */ > if (!bus->msgs) { > - dev_err(bus->dev, "bus in unknown state\n"); > + dev_err(bus->dev, "bus in unknown state irq_status: 0x%x\n", > + bus->irq_status); > bus->cmd_err = -EIO; > - if (bus->master_state != ASPEED_I2C_MASTER_STOP) > + if (bus->master_state != ASPEED_I2C_MASTER_STOP && > + bus->master_state != ASPEED_I2C_MASTER_INACTIVE) > aspeed_i2c_do_stop(bus); > goto out_no_complete; > } > @@ -427,8 +425,14 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > * then update the state and handle the new state below. > */ > if (bus->master_state == ASPEED_I2C_MASTER_START) { > - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { > - pr_devel("no slave present at %02x\n", msg->addr); > + if (unlikely(!(bus->irq_status & ASPEED_I2CD_INTR_TX_ACK))) { > + if (unlikely(!(bus->irq_status & > + ASPEED_I2CD_INTR_TX_NAK))) { > + bus->cmd_err = -ENXIO; > + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; > + goto out_complete; > + } > + pr_devel("no slave present at %02x", msg->addr); Missing line feed character > status_ack |= ASPEED_I2CD_INTR_TX_NAK; > bus->cmd_err = -ENXIO; > aspeed_i2c_do_stop(bus); > @@ -447,11 +451,12 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > > switch (bus->master_state) { > case ASPEED_I2C_MASTER_TX: > - if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) { > + if (unlikely(bus->irq_status & ASPEED_I2CD_INTR_TX_NAK)) { > dev_dbg(bus->dev, "slave NACKed TX\n"); > status_ack |= ASPEED_I2CD_INTR_TX_NAK; > goto error_and_stop; > - } else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { > + } else if (unlikely(!(bus->irq_status & > + ASPEED_I2CD_INTR_TX_ACK))) { > dev_err(bus->dev, "slave failed to ACK TX\n"); > goto error_and_stop; > } > @@ -470,11 +475,11 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > goto out_no_complete; > case ASPEED_I2C_MASTER_RX_FIRST: > /* RX may not have completed yet (only address cycle) */ > - if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE)) > + if (!(bus->irq_status & ASPEED_I2CD_INTR_RX_DONE)) > goto out_no_complete; > /* fallthrough intended */ > case ASPEED_I2C_MASTER_RX: > - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) { > + if (unlikely(!(bus->irq_status & ASPEED_I2CD_INTR_RX_DONE))) { > dev_err(bus->dev, "master failed to RX\n"); > goto error_and_stop; > } > @@ -505,8 +510,11 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > } > goto out_no_complete; > case ASPEED_I2C_MASTER_STOP: > - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) { > - dev_err(bus->dev, "master failed to STOP\n"); > + if (unlikely(!(bus->irq_status & > + ASPEED_I2CD_INTR_NORMAL_STOP))) { > + dev_err(bus->dev, > + "master failed to STOP irq_status:0x%x\n", > + bus->irq_status); > bus->cmd_err = -EIO; > /* Do not STOP as we have already tried. */ > } else { > @@ -518,7 +526,7 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > case ASPEED_I2C_MASTER_INACTIVE: > dev_err(bus->dev, > "master received interrupt 0x%08x, but is inactive\n", > - irq_status); > + bus->irq_status); > bus->cmd_err = -EIO; > /* Do not STOP as we should be inactive. */ > goto out_complete; > @@ -540,33 +548,40 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) > bus->master_xfer_result = bus->msgs_index + 1; > complete(&bus->cmd_complete); > out_no_complete: > - if (irq_status != status_ack) > - dev_err(bus->dev, > - "irq handled != irq. expected 0x%08x, but was 0x%08x\n", > - irq_status, status_ack); > - return !!irq_status; > + bus->irq_status ^= status_ack; > + return !bus->irq_status; > } > > static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) > { > struct aspeed_i2c_bus *bus = dev_id; > - bool ret; > + u32 irq_received; > > spin_lock(&bus->lock); > + irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG); > + bus->irq_status = irq_received; > > #if IS_ENABLED(CONFIG_I2C_SLAVE) > - if (aspeed_i2c_slave_irq(bus)) { > - dev_dbg(bus->dev, "irq handled by slave.\n"); > - ret = true; > - goto out; > + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) { > + if (!aspeed_i2c_master_irq(bus)) > + aspeed_i2c_slave_irq(bus); > + } else { > + if (!aspeed_i2c_slave_irq(bus)) > + aspeed_i2c_master_irq(bus); > } > +#else > + aspeed_i2c_master_irq(bus); > #endif /* CONFIG_I2C_SLAVE */ > > - ret = aspeed_i2c_master_irq(bus); > + if (bus->irq_status) > + dev_err(bus->dev, > + "irq handled != irq. expected 0x%08x, but was 0x%08x\n", > + irq_received, irq_received ^ bus->irq_status); > > -out: > + /* Ack all interrupt bits. */ > + writel(irq_received, bus->base + ASPEED_I2C_INTR_STS_REG); > spin_unlock(&bus->lock); > - return ret ? IRQ_HANDLED : IRQ_NONE; > + return bus->irq_status ? IRQ_NONE : IRQ_HANDLED; > } > > static int aspeed_i2c_master_xfer(struct i2c_adapter *adap, >
Thanks James for the review. Please see my inline answers. On 7/23/2018 11:10 AM, James Feist wrote: > On 07/23/2018 10:48 AM, Jae Hyun Yoo wrote: >> In most of cases, interrupt bits are set one by one but there are >> also a lot of other cases that Aspeed I2C IP sends multiple >> interrupt bits with combining master and slave events using a >> single interrupt call. It happens much in multi-master environment > > much more > Thanks! Will fix it. >> than single-master. For an example, when master is waiting for a >> NORMAL_STOP interrupt in its MASTER_STOP state, SLAVE_MATCH and >> RX_DONE interrupts could come along with the NORMAL_STOP in case of >> an another master immediately sends data just after acquiring the >> bus. In this case, the NORMAL_STOP interrupt should be handled >> by master_irq and the SLAVE_MATCH and RX_DONE interrupts should be >> handled by slave_irq. This commit modifies irq hadling logic to >> handle the master/slave combined events properly. >> >> Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> >> --- >> drivers/i2c/busses/i2c-aspeed.c | 137 ++++++++++++++++++-------------- >> 1 file changed, 76 insertions(+), 61 deletions(-) >> >> diff --git a/drivers/i2c/busses/i2c-aspeed.c >> b/drivers/i2c/busses/i2c-aspeed.c >> index efb89422d496..24d43f143a55 100644 >> --- a/drivers/i2c/busses/i2c-aspeed.c >> +++ b/drivers/i2c/busses/i2c-aspeed.c >> @@ -82,6 +82,11 @@ >> #define ASPEED_I2CD_INTR_RX_DONE BIT(2) >> #define ASPEED_I2CD_INTR_TX_NAK BIT(1) >> #define ASPEED_I2CD_INTR_TX_ACK BIT(0) >> +#define ASPEED_I2CD_INTR_ERRORS \ >> + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ >> + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ >> + ASPEED_I2CD_INTR_ABNORMAL | \ >> + ASPEED_I2CD_INTR_ARBIT_LOSS) >> #define ASPEED_I2CD_INTR_ALL \ >> (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ >> ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \ >> @@ -150,6 +155,7 @@ struct aspeed_i2c_bus { >> int cmd_err; >> /* Protected only by i2c_lock_bus */ >> int master_xfer_result; >> + u32 irq_status; >> #if IS_ENABLED(CONFIG_I2C_SLAVE) >> struct i2c_client *slave; >> enum aspeed_i2c_slave_state slave_state; >> @@ -229,36 +235,30 @@ static int aspeed_i2c_recover_bus(struct >> aspeed_i2c_bus *bus) >> #if IS_ENABLED(CONFIG_I2C_SLAVE) >> static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) >> { >> - u32 command, irq_status, status_ack = 0; >> + u32 command, status_ack = 0; >> struct i2c_client *slave = bus->slave; >> - bool irq_handled = true; >> u8 value; >> - if (!slave) { >> - irq_handled = false; >> - goto out; >> - } >> + if (!slave) >> + return false; >> command = readl(bus->base + ASPEED_I2C_CMD_REG); >> - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); >> /* Slave was requested, restart state machine. */ >> - if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { >> + if (bus->irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { >> status_ack |= ASPEED_I2CD_INTR_SLAVE_MATCH; >> bus->slave_state = ASPEED_I2C_SLAVE_START; >> } >> /* Slave is not currently active, irq was for someone else. */ >> - if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) { >> - irq_handled = false; >> - goto out; >> - } >> + if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) >> + return false; >> dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n", >> - irq_status, command); >> + bus->irq_status, command); >> /* Slave was sent something. */ >> - if (irq_status & ASPEED_I2CD_INTR_RX_DONE) { >> + if (bus->irq_status & ASPEED_I2CD_INTR_RX_DONE) { >> value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; >> /* Handle address frame. */ >> if (bus->slave_state == ASPEED_I2C_SLAVE_START) { >> @@ -273,28 +273,29 @@ static bool aspeed_i2c_slave_irq(struct >> aspeed_i2c_bus *bus) >> } >> /* Slave was asked to stop. */ >> - if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { >> + if (bus->irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { >> status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP; >> bus->slave_state = ASPEED_I2C_SLAVE_STOP; >> } >> - if (irq_status & ASPEED_I2CD_INTR_TX_NAK) { >> + if (bus->irq_status & ASPEED_I2CD_INTR_TX_NAK) { >> status_ack |= ASPEED_I2CD_INTR_TX_NAK; >> bus->slave_state = ASPEED_I2C_SLAVE_STOP; >> } >> + if (bus->irq_status & ASPEED_I2CD_INTR_TX_ACK) { >> + status_ack |= ASPEED_I2CD_INTR_TX_ACK; >> + } >> switch (bus->slave_state) { >> case ASPEED_I2C_SLAVE_READ_REQUESTED: >> - if (irq_status & ASPEED_I2CD_INTR_TX_ACK) >> + if (bus->irq_status & ASPEED_I2CD_INTR_TX_ACK) >> dev_err(bus->dev, "Unexpected ACK on read request.\n"); >> bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED; >> - >> i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); >> writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); >> writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); >> break; >> case ASPEED_I2C_SLAVE_READ_PROCESSED: >> - status_ack |= ASPEED_I2CD_INTR_TX_ACK; >> - if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK)) >> + if (!(bus->irq_status & ASPEED_I2CD_INTR_TX_ACK)) >> dev_err(bus->dev, >> "Expected ACK after processed read.\n"); >> i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); >> @@ -317,14 +318,8 @@ static bool aspeed_i2c_slave_irq(struct >> aspeed_i2c_bus *bus) >> break; >> } >> - if (status_ack != irq_status) >> - dev_err(bus->dev, >> - "irq handled != irq. expected %x, but was %x\n", >> - irq_status, status_ack); >> - writel(status_ack, bus->base + ASPEED_I2C_INTR_STS_REG); >> - >> -out: >> - return irq_handled; >> + bus->irq_status ^= status_ack; >> + return !bus->irq_status; >> } >> #endif /* CONFIG_I2C_SLAVE */ >> @@ -382,19 +377,19 @@ static int aspeed_i2c_is_irq_error(u32 irq_status) >> static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) >> { >> - u32 irq_status, status_ack = 0, command = 0; >> + u32 status_ack = 0, command = 0; >> struct i2c_msg *msg; >> u8 recv_byte; >> int ret; >> - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); >> - /* Ack all interrupt bits. */ >> - writel(irq_status, bus->base + ASPEED_I2C_INTR_STS_REG); >> - >> - if (irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { >> + if (bus->irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { >> bus->master_state = ASPEED_I2C_MASTER_INACTIVE; >> status_ack |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE; >> goto out_complete; >> + } else { >> + /* Master is not currently active, irq was for someone else. */ >> + if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE) >> + goto out_no_complete; >> } >> /* >> @@ -402,20 +397,23 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> * should clear the command queue effectively taking us back to the >> * INACTIVE state. >> */ >> - ret = aspeed_i2c_is_irq_error(irq_status); >> - if (ret < 0) { >> + ret = aspeed_i2c_is_irq_error(bus->irq_status); >> + if (ret) { >> dev_dbg(bus->dev, "received error interrupt: 0x%08x\n", >> - irq_status); >> + bus->irq_status); >> bus->cmd_err = ret; >> bus->master_state = ASPEED_I2C_MASTER_INACTIVE; >> + status_ack |= (bus->irq_status & ASPEED_I2CD_INTR_ERRORS); >> goto out_complete; >> } >> /* We are in an invalid state; reset bus to a known state. */ >> if (!bus->msgs) { >> - dev_err(bus->dev, "bus in unknown state\n"); >> + dev_err(bus->dev, "bus in unknown state irq_status: 0x%x\n", >> + bus->irq_status); >> bus->cmd_err = -EIO; >> - if (bus->master_state != ASPEED_I2C_MASTER_STOP) >> + if (bus->master_state != ASPEED_I2C_MASTER_STOP && >> + bus->master_state != ASPEED_I2C_MASTER_INACTIVE) >> aspeed_i2c_do_stop(bus); >> goto out_no_complete; >> } >> @@ -427,8 +425,14 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> * then update the state and handle the new state below. >> */ >> if (bus->master_state == ASPEED_I2C_MASTER_START) { >> - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { >> - pr_devel("no slave present at %02x\n", msg->addr); >> + if (unlikely(!(bus->irq_status & ASPEED_I2CD_INTR_TX_ACK))) { >> + if (unlikely(!(bus->irq_status & >> + ASPEED_I2CD_INTR_TX_NAK))) { >> + bus->cmd_err = -ENXIO; >> + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; >> + goto out_complete; >> + } >> + pr_devel("no slave present at %02x", msg->addr); > Missing line feed character Thanks for your pointing it out. Will add '\n' at the end of the message. >> status_ack |= ASPEED_I2CD_INTR_TX_NAK; >> bus->cmd_err = -ENXIO; >> aspeed_i2c_do_stop(bus); >> @@ -447,11 +451,12 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> switch (bus->master_state) { >> case ASPEED_I2C_MASTER_TX: >> - if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) { >> + if (unlikely(bus->irq_status & ASPEED_I2CD_INTR_TX_NAK)) { >> dev_dbg(bus->dev, "slave NACKed TX\n"); >> status_ack |= ASPEED_I2CD_INTR_TX_NAK; >> goto error_and_stop; >> - } else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { >> + } else if (unlikely(!(bus->irq_status & >> + ASPEED_I2CD_INTR_TX_ACK))) { >> dev_err(bus->dev, "slave failed to ACK TX\n"); >> goto error_and_stop; >> } >> @@ -470,11 +475,11 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> goto out_no_complete; >> case ASPEED_I2C_MASTER_RX_FIRST: >> /* RX may not have completed yet (only address cycle) */ >> - if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE)) >> + if (!(bus->irq_status & ASPEED_I2CD_INTR_RX_DONE)) >> goto out_no_complete; >> /* fallthrough intended */ >> case ASPEED_I2C_MASTER_RX: >> - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) { >> + if (unlikely(!(bus->irq_status & ASPEED_I2CD_INTR_RX_DONE))) { >> dev_err(bus->dev, "master failed to RX\n"); >> goto error_and_stop; >> } >> @@ -505,8 +510,11 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> } >> goto out_no_complete; >> case ASPEED_I2C_MASTER_STOP: >> - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) { >> - dev_err(bus->dev, "master failed to STOP\n"); >> + if (unlikely(!(bus->irq_status & >> + ASPEED_I2CD_INTR_NORMAL_STOP))) { >> + dev_err(bus->dev, >> + "master failed to STOP irq_status:0x%x\n", >> + bus->irq_status); >> bus->cmd_err = -EIO; >> /* Do not STOP as we have already tried. */ >> } else { >> @@ -518,7 +526,7 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> case ASPEED_I2C_MASTER_INACTIVE: >> dev_err(bus->dev, >> "master received interrupt 0x%08x, but is inactive\n", >> - irq_status); >> + bus->irq_status); >> bus->cmd_err = -EIO; >> /* Do not STOP as we should be inactive. */ >> goto out_complete; >> @@ -540,33 +548,40 @@ static bool aspeed_i2c_master_irq(struct >> aspeed_i2c_bus *bus) >> bus->master_xfer_result = bus->msgs_index + 1; >> complete(&bus->cmd_complete); >> out_no_complete: >> - if (irq_status != status_ack) >> - dev_err(bus->dev, >> - "irq handled != irq. expected 0x%08x, but was 0x%08x\n", >> - irq_status, status_ack); >> - return !!irq_status; >> + bus->irq_status ^= status_ack; >> + return !bus->irq_status; >> } >> static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) >> { >> struct aspeed_i2c_bus *bus = dev_id; >> - bool ret; >> + u32 irq_received; >> spin_lock(&bus->lock); >> + irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG); >> + bus->irq_status = irq_received; >> #if IS_ENABLED(CONFIG_I2C_SLAVE) >> - if (aspeed_i2c_slave_irq(bus)) { >> - dev_dbg(bus->dev, "irq handled by slave.\n"); >> - ret = true; >> - goto out; >> + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) { >> + if (!aspeed_i2c_master_irq(bus)) >> + aspeed_i2c_slave_irq(bus); >> + } else { >> + if (!aspeed_i2c_slave_irq(bus)) >> + aspeed_i2c_master_irq(bus); >> } >> +#else >> + aspeed_i2c_master_irq(bus); >> #endif /* CONFIG_I2C_SLAVE */ >> - ret = aspeed_i2c_master_irq(bus); >> + if (bus->irq_status) >> + dev_err(bus->dev, >> + "irq handled != irq. expected 0x%08x, but was 0x%08x\n", >> + irq_received, irq_received ^ bus->irq_status); >> -out: >> + /* Ack all interrupt bits. */ >> + writel(irq_received, bus->base + ASPEED_I2C_INTR_STS_REG); >> spin_unlock(&bus->lock); >> - return ret ? IRQ_HANDLED : IRQ_NONE; >> + return bus->irq_status ? IRQ_NONE : IRQ_HANDLED; >> } >> static int aspeed_i2c_master_xfer(struct i2c_adapter *adap, >>
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c index efb89422d496..24d43f143a55 100644 --- a/drivers/i2c/busses/i2c-aspeed.c +++ b/drivers/i2c/busses/i2c-aspeed.c @@ -82,6 +82,11 @@ #define ASPEED_I2CD_INTR_RX_DONE BIT(2) #define ASPEED_I2CD_INTR_TX_NAK BIT(1) #define ASPEED_I2CD_INTR_TX_ACK BIT(0) +#define ASPEED_I2CD_INTR_ERRORS \ + (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ + ASPEED_I2CD_INTR_SCL_TIMEOUT | \ + ASPEED_I2CD_INTR_ABNORMAL | \ + ASPEED_I2CD_INTR_ARBIT_LOSS) #define ASPEED_I2CD_INTR_ALL \ (ASPEED_I2CD_INTR_SDA_DL_TIMEOUT | \ ASPEED_I2CD_INTR_BUS_RECOVER_DONE | \ @@ -150,6 +155,7 @@ struct aspeed_i2c_bus { int cmd_err; /* Protected only by i2c_lock_bus */ int master_xfer_result; + u32 irq_status; #if IS_ENABLED(CONFIG_I2C_SLAVE) struct i2c_client *slave; enum aspeed_i2c_slave_state slave_state; @@ -229,36 +235,30 @@ static int aspeed_i2c_recover_bus(struct aspeed_i2c_bus *bus) #if IS_ENABLED(CONFIG_I2C_SLAVE) static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) { - u32 command, irq_status, status_ack = 0; + u32 command, status_ack = 0; struct i2c_client *slave = bus->slave; - bool irq_handled = true; u8 value; - if (!slave) { - irq_handled = false; - goto out; - } + if (!slave) + return false; command = readl(bus->base + ASPEED_I2C_CMD_REG); - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); /* Slave was requested, restart state machine. */ - if (irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { + if (bus->irq_status & ASPEED_I2CD_INTR_SLAVE_MATCH) { status_ack |= ASPEED_I2CD_INTR_SLAVE_MATCH; bus->slave_state = ASPEED_I2C_SLAVE_START; } /* Slave is not currently active, irq was for someone else. */ - if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) { - irq_handled = false; - goto out; - } + if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) + return false; dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n", - irq_status, command); + bus->irq_status, command); /* Slave was sent something. */ - if (irq_status & ASPEED_I2CD_INTR_RX_DONE) { + if (bus->irq_status & ASPEED_I2CD_INTR_RX_DONE) { value = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8; /* Handle address frame. */ if (bus->slave_state == ASPEED_I2C_SLAVE_START) { @@ -273,28 +273,29 @@ static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) } /* Slave was asked to stop. */ - if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { + if (bus->irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) { status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP; bus->slave_state = ASPEED_I2C_SLAVE_STOP; } - if (irq_status & ASPEED_I2CD_INTR_TX_NAK) { + if (bus->irq_status & ASPEED_I2CD_INTR_TX_NAK) { status_ack |= ASPEED_I2CD_INTR_TX_NAK; bus->slave_state = ASPEED_I2C_SLAVE_STOP; } + if (bus->irq_status & ASPEED_I2CD_INTR_TX_ACK) { + status_ack |= ASPEED_I2CD_INTR_TX_ACK; + } switch (bus->slave_state) { case ASPEED_I2C_SLAVE_READ_REQUESTED: - if (irq_status & ASPEED_I2CD_INTR_TX_ACK) + if (bus->irq_status & ASPEED_I2CD_INTR_TX_ACK) dev_err(bus->dev, "Unexpected ACK on read request.\n"); bus->slave_state = ASPEED_I2C_SLAVE_READ_PROCESSED; - i2c_slave_event(slave, I2C_SLAVE_READ_REQUESTED, &value); writel(value, bus->base + ASPEED_I2C_BYTE_BUF_REG); writel(ASPEED_I2CD_S_TX_CMD, bus->base + ASPEED_I2C_CMD_REG); break; case ASPEED_I2C_SLAVE_READ_PROCESSED: - status_ack |= ASPEED_I2CD_INTR_TX_ACK; - if (!(irq_status & ASPEED_I2CD_INTR_TX_ACK)) + if (!(bus->irq_status & ASPEED_I2CD_INTR_TX_ACK)) dev_err(bus->dev, "Expected ACK after processed read.\n"); i2c_slave_event(slave, I2C_SLAVE_READ_PROCESSED, &value); @@ -317,14 +318,8 @@ static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus) break; } - if (status_ack != irq_status) - dev_err(bus->dev, - "irq handled != irq. expected %x, but was %x\n", - irq_status, status_ack); - writel(status_ack, bus->base + ASPEED_I2C_INTR_STS_REG); - -out: - return irq_handled; + bus->irq_status ^= status_ack; + return !bus->irq_status; } #endif /* CONFIG_I2C_SLAVE */ @@ -382,19 +377,19 @@ static int aspeed_i2c_is_irq_error(u32 irq_status) static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) { - u32 irq_status, status_ack = 0, command = 0; + u32 status_ack = 0, command = 0; struct i2c_msg *msg; u8 recv_byte; int ret; - irq_status = readl(bus->base + ASPEED_I2C_INTR_STS_REG); - /* Ack all interrupt bits. */ - writel(irq_status, bus->base + ASPEED_I2C_INTR_STS_REG); - - if (irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { + if (bus->irq_status & ASPEED_I2CD_INTR_BUS_RECOVER_DONE) { bus->master_state = ASPEED_I2C_MASTER_INACTIVE; status_ack |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE; goto out_complete; + } else { + /* Master is not currently active, irq was for someone else. */ + if (bus->master_state == ASPEED_I2C_MASTER_INACTIVE) + goto out_no_complete; } /* @@ -402,20 +397,23 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) * should clear the command queue effectively taking us back to the * INACTIVE state. */ - ret = aspeed_i2c_is_irq_error(irq_status); - if (ret < 0) { + ret = aspeed_i2c_is_irq_error(bus->irq_status); + if (ret) { dev_dbg(bus->dev, "received error interrupt: 0x%08x\n", - irq_status); + bus->irq_status); bus->cmd_err = ret; bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + status_ack |= (bus->irq_status & ASPEED_I2CD_INTR_ERRORS); goto out_complete; } /* We are in an invalid state; reset bus to a known state. */ if (!bus->msgs) { - dev_err(bus->dev, "bus in unknown state\n"); + dev_err(bus->dev, "bus in unknown state irq_status: 0x%x\n", + bus->irq_status); bus->cmd_err = -EIO; - if (bus->master_state != ASPEED_I2C_MASTER_STOP) + if (bus->master_state != ASPEED_I2C_MASTER_STOP && + bus->master_state != ASPEED_I2C_MASTER_INACTIVE) aspeed_i2c_do_stop(bus); goto out_no_complete; } @@ -427,8 +425,14 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) * then update the state and handle the new state below. */ if (bus->master_state == ASPEED_I2C_MASTER_START) { - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { - pr_devel("no slave present at %02x\n", msg->addr); + if (unlikely(!(bus->irq_status & ASPEED_I2CD_INTR_TX_ACK))) { + if (unlikely(!(bus->irq_status & + ASPEED_I2CD_INTR_TX_NAK))) { + bus->cmd_err = -ENXIO; + bus->master_state = ASPEED_I2C_MASTER_INACTIVE; + goto out_complete; + } + pr_devel("no slave present at %02x", msg->addr); status_ack |= ASPEED_I2CD_INTR_TX_NAK; bus->cmd_err = -ENXIO; aspeed_i2c_do_stop(bus); @@ -447,11 +451,12 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) switch (bus->master_state) { case ASPEED_I2C_MASTER_TX: - if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) { + if (unlikely(bus->irq_status & ASPEED_I2CD_INTR_TX_NAK)) { dev_dbg(bus->dev, "slave NACKed TX\n"); status_ack |= ASPEED_I2CD_INTR_TX_NAK; goto error_and_stop; - } else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) { + } else if (unlikely(!(bus->irq_status & + ASPEED_I2CD_INTR_TX_ACK))) { dev_err(bus->dev, "slave failed to ACK TX\n"); goto error_and_stop; } @@ -470,11 +475,11 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) goto out_no_complete; case ASPEED_I2C_MASTER_RX_FIRST: /* RX may not have completed yet (only address cycle) */ - if (!(irq_status & ASPEED_I2CD_INTR_RX_DONE)) + if (!(bus->irq_status & ASPEED_I2CD_INTR_RX_DONE)) goto out_no_complete; /* fallthrough intended */ case ASPEED_I2C_MASTER_RX: - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) { + if (unlikely(!(bus->irq_status & ASPEED_I2CD_INTR_RX_DONE))) { dev_err(bus->dev, "master failed to RX\n"); goto error_and_stop; } @@ -505,8 +510,11 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) } goto out_no_complete; case ASPEED_I2C_MASTER_STOP: - if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) { - dev_err(bus->dev, "master failed to STOP\n"); + if (unlikely(!(bus->irq_status & + ASPEED_I2CD_INTR_NORMAL_STOP))) { + dev_err(bus->dev, + "master failed to STOP irq_status:0x%x\n", + bus->irq_status); bus->cmd_err = -EIO; /* Do not STOP as we have already tried. */ } else { @@ -518,7 +526,7 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) case ASPEED_I2C_MASTER_INACTIVE: dev_err(bus->dev, "master received interrupt 0x%08x, but is inactive\n", - irq_status); + bus->irq_status); bus->cmd_err = -EIO; /* Do not STOP as we should be inactive. */ goto out_complete; @@ -540,33 +548,40 @@ static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus) bus->master_xfer_result = bus->msgs_index + 1; complete(&bus->cmd_complete); out_no_complete: - if (irq_status != status_ack) - dev_err(bus->dev, - "irq handled != irq. expected 0x%08x, but was 0x%08x\n", - irq_status, status_ack); - return !!irq_status; + bus->irq_status ^= status_ack; + return !bus->irq_status; } static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id) { struct aspeed_i2c_bus *bus = dev_id; - bool ret; + u32 irq_received; spin_lock(&bus->lock); + irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG); + bus->irq_status = irq_received; #if IS_ENABLED(CONFIG_I2C_SLAVE) - if (aspeed_i2c_slave_irq(bus)) { - dev_dbg(bus->dev, "irq handled by slave.\n"); - ret = true; - goto out; + if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) { + if (!aspeed_i2c_master_irq(bus)) + aspeed_i2c_slave_irq(bus); + } else { + if (!aspeed_i2c_slave_irq(bus)) + aspeed_i2c_master_irq(bus); } +#else + aspeed_i2c_master_irq(bus); #endif /* CONFIG_I2C_SLAVE */ - ret = aspeed_i2c_master_irq(bus); + if (bus->irq_status) + dev_err(bus->dev, + "irq handled != irq. expected 0x%08x, but was 0x%08x\n", + irq_received, irq_received ^ bus->irq_status); -out: + /* Ack all interrupt bits. */ + writel(irq_received, bus->base + ASPEED_I2C_INTR_STS_REG); spin_unlock(&bus->lock); - return ret ? IRQ_HANDLED : IRQ_NONE; + return bus->irq_status ? IRQ_NONE : IRQ_HANDLED; } static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
In most of cases, interrupt bits are set one by one but there are also a lot of other cases that Aspeed I2C IP sends multiple interrupt bits with combining master and slave events using a single interrupt call. It happens much in multi-master environment than single-master. For an example, when master is waiting for a NORMAL_STOP interrupt in its MASTER_STOP state, SLAVE_MATCH and RX_DONE interrupts could come along with the NORMAL_STOP in case of an another master immediately sends data just after acquiring the bus. In this case, the NORMAL_STOP interrupt should be handled by master_irq and the SLAVE_MATCH and RX_DONE interrupts should be handled by slave_irq. This commit modifies irq hadling logic to handle the master/slave combined events properly. Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@linux.intel.com> --- drivers/i2c/busses/i2c-aspeed.c | 137 ++++++++++++++++++-------------- 1 file changed, 76 insertions(+), 61 deletions(-)