@@ -317,7 +317,7 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
switch (bus->slave_state) {
case ASPEED_I2C_SLAVE_READ_REQUESTED:
if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_ACK))
- dev_err(bus->dev, "Unexpected ACK on read request.\n");
+ dev_dbg(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);
@@ -325,7 +325,7 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
break;
case ASPEED_I2C_SLAVE_READ_PROCESSED:
if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
- dev_err(bus->dev,
+ dev_dbg(bus->dev,
"Expected ACK after processed read.\n");
break;
}
@@ -354,7 +354,7 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
/* Slave was just started. Waiting for the next event. */;
break;
default:
- dev_err(bus->dev, "unknown slave_state: %d\n",
+ dev_dbg(bus->dev, "unknown slave_state: %d\n",
bus->slave_state);
bus->slave_state = ASPEED_I2C_SLAVE_INACTIVE;
break;
@@ -459,7 +459,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
/* We are in an invalid state; reset bus to a known state. */
if (!bus->msgs) {
- dev_err(bus->dev, "bus in unknown state. irq_status: 0x%x\n",
+ dev_dbg(bus->dev, "bus in unknown state. irq_status: 0x%x\n",
irq_status);
bus->cmd_err = -EIO;
if (bus->master_state != ASPEED_I2C_MASTER_STOP &&
@@ -523,7 +523,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
goto error_and_stop;
} else if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
- dev_err(bus->dev, "slave failed to ACK TX\n");
+ dev_dbg(bus->dev, "slave failed to ACK TX\n");
goto error_and_stop;
}
irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
@@ -546,7 +546,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
fallthrough;
case ASPEED_I2C_MASTER_RX:
if (unlikely(!(irq_status & ASPEED_I2CD_INTR_RX_DONE))) {
- dev_err(bus->dev, "master failed to RX\n");
+ dev_dbg(bus->dev, "master failed to RX\n");
goto error_and_stop;
}
irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
@@ -577,7 +577,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
goto out_no_complete;
case ASPEED_I2C_MASTER_STOP:
if (unlikely(!(irq_status & ASPEED_I2CD_INTR_NORMAL_STOP))) {
- dev_err(bus->dev,
+ dev_dbg(bus->dev,
"master failed to STOP. irq_status:0x%x\n",
irq_status);
bus->cmd_err = -EIO;
@@ -589,7 +589,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
goto out_complete;
case ASPEED_I2C_MASTER_INACTIVE:
- dev_err(bus->dev,
+ dev_dbg(bus->dev,
"master received interrupt 0x%08x, but is inactive\n",
irq_status);
bus->cmd_err = -EIO;
@@ -665,7 +665,7 @@ static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
irq_remaining &= ~irq_handled;
if (irq_remaining)
- dev_err(bus->dev,
+ dev_dbg(bus->dev,
"irq handled != irq. expected 0x%08x, but was 0x%08x\n",
irq_received, irq_handled);
In interrupt context, using dev_err() can potentially cause latency or affect system responsiveness due to printing to console. In our scenario, under certain conditions, i2c1 repeatedly printed "irq handled != irq. expected ..." around 20 times within 1 second. Each dev_err() log introduced approximately 10ms of blocking time, which delayed the handling of other interrupts — for example, i2c2. At the time, i2c2 was performing a PMBus firmware upgrade. The target device on i2c2 was time-sensitive, and the upgrade protocol was non-retryable. As a result, the delay caused by frequent error logging led to a timeout and ultimately a failed firmware upgrade. Frequent error printing in interrupt context can be dangerous, as it introduces latency and interferes with time-critical tasks. This patch changes the log level from dev_err() to dev_dbg() to reduce potential impact. Signed-off-by: Jian Zhang <zhangjian.3032@bytedance.com> --- drivers/i2c/busses/i2c-aspeed.c | 18 +++++++++--------- 1 file changed, 9 insertions(+), 9 deletions(-)