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 <[email protected]>
---
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);
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,
--
2.18.0
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 <[email protected]>
> ---
> 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 <[email protected]>
>> ---
>> 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,
>>