[PATCH] Revert "i2c: aspeed: Handle master/slave combined irq events properly"
Jae Hyun Yoo
jae.hyun.yoo at linux.intel.com
Wed Sep 12 08:24:45 AEST 2018
This reverts commit 3e9efc3299dd "i2c: aspeed: Handle master/slave
combined irq events properly" to fix an issue which is reported
from QEMU v3.0 environment.
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo at linux.intel.com>
Cc: Guenter Roeck <linux at roeck-us.net>
---
drivers/i2c/busses/i2c-aspeed.c | 131 ++++++++++++++------------------
1 file changed, 55 insertions(+), 76 deletions(-)
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index c258c4d9a4c0..a4f956c6d567 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -82,11 +82,6 @@
#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_MASTER_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 | \
@@ -232,26 +227,32 @@ static int aspeed_i2c_recover_bus(struct aspeed_i2c_bus *bus)
}
#if IS_ENABLED(CONFIG_I2C_SLAVE)
-static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
+static bool aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus)
{
- u32 command, irq_handled = 0;
+ u32 command, irq_status, status_ack = 0;
struct i2c_client *slave = bus->slave;
+ bool irq_handled = true;
u8 value;
- if (!slave)
- return 0;
+ if (!slave) {
+ irq_handled = false;
+ goto out;
+ }
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) {
- irq_handled |= 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)
- return irq_handled;
+ if (bus->slave_state == ASPEED_I2C_SLAVE_STOP) {
+ irq_handled = false;
+ goto out;
+ }
dev_dbg(bus->dev, "slave irq status 0x%08x, cmd 0x%08x\n",
irq_status, command);
@@ -268,31 +269,31 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
bus->slave_state =
ASPEED_I2C_SLAVE_WRITE_REQUESTED;
}
- irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
+ status_ack |= ASPEED_I2CD_INTR_RX_DONE;
}
/* Slave was asked to stop. */
if (irq_status & ASPEED_I2CD_INTR_NORMAL_STOP) {
- irq_handled |= 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) {
- irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
+ status_ack |= ASPEED_I2CD_INTR_TX_NAK;
bus->slave_state = ASPEED_I2C_SLAVE_STOP;
}
- if (irq_status & ASPEED_I2CD_INTR_TX_ACK)
- irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
switch (bus->slave_state) {
case ASPEED_I2C_SLAVE_READ_REQUESTED:
if (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))
dev_err(bus->dev,
"Expected ACK after processed read.\n");
@@ -316,6 +317,13 @@ static u32 aspeed_i2c_slave_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
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;
}
#endif /* CONFIG_I2C_SLAVE */
@@ -372,21 +380,21 @@ static int aspeed_i2c_is_irq_error(u32 irq_status)
return 0;
}
-static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
+static bool aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus)
{
- u32 irq_handled = 0, command = 0;
+ u32 irq_status, 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) {
bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
- irq_handled |= ASPEED_I2CD_INTR_BUS_RECOVER_DONE;
+ 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;
}
/*
@@ -395,22 +403,19 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
* INACTIVE state.
*/
ret = aspeed_i2c_is_irq_error(irq_status);
- if (ret) {
+ if (ret < 0) {
dev_dbg(bus->dev, "received error interrupt: 0x%08x\n",
irq_status);
bus->cmd_err = ret;
bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
- irq_handled |= (irq_status & ASPEED_I2CD_INTR_MASTER_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. irq_status: 0x%x\n",
- irq_status);
+ dev_err(bus->dev, "bus in unknown state\n");
bus->cmd_err = -EIO;
- if (bus->master_state != ASPEED_I2C_MASTER_STOP &&
- bus->master_state != ASPEED_I2C_MASTER_INACTIVE)
+ if (bus->master_state != ASPEED_I2C_MASTER_STOP)
aspeed_i2c_do_stop(bus);
goto out_no_complete;
}
@@ -423,18 +428,13 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
*/
if (bus->master_state == ASPEED_I2C_MASTER_START) {
if (unlikely(!(irq_status & ASPEED_I2CD_INTR_TX_ACK))) {
- if (unlikely(!(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\n", msg->addr);
- irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
+ status_ack |= ASPEED_I2CD_INTR_TX_NAK;
bus->cmd_err = -ENXIO;
aspeed_i2c_do_stop(bus);
goto out_no_complete;
}
- irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
+ status_ack |= ASPEED_I2CD_INTR_TX_ACK;
if (msg->len == 0) { /* SMBUS_QUICK */
aspeed_i2c_do_stop(bus);
goto out_no_complete;
@@ -449,13 +449,13 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
case ASPEED_I2C_MASTER_TX:
if (unlikely(irq_status & ASPEED_I2CD_INTR_TX_NAK)) {
dev_dbg(bus->dev, "slave NACKed TX\n");
- irq_handled |= ASPEED_I2CD_INTR_TX_NAK;
+ status_ack |= 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");
goto error_and_stop;
}
- irq_handled |= ASPEED_I2CD_INTR_TX_ACK;
+ status_ack |= ASPEED_I2CD_INTR_TX_ACK;
/* fallthrough intended */
case ASPEED_I2C_MASTER_TX_FIRST:
if (bus->buf_index < msg->len) {
@@ -478,7 +478,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
dev_err(bus->dev, "master failed to RX\n");
goto error_and_stop;
}
- irq_handled |= ASPEED_I2CD_INTR_RX_DONE;
+ status_ack |= ASPEED_I2CD_INTR_RX_DONE;
recv_byte = readl(bus->base + ASPEED_I2C_BYTE_BUF_REG) >> 8;
msg->buf[bus->buf_index++] = recv_byte;
@@ -506,13 +506,11 @@ 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,
- "master failed to STOP. irq_status:0x%x\n",
- irq_status);
+ dev_err(bus->dev, "master failed to STOP\n");
bus->cmd_err = -EIO;
/* Do not STOP as we have already tried. */
} else {
- irq_handled |= ASPEED_I2CD_INTR_NORMAL_STOP;
+ status_ack |= ASPEED_I2CD_INTR_NORMAL_STOP;
}
bus->master_state = ASPEED_I2C_MASTER_INACTIVE;
@@ -542,52 +540,33 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
bus->master_xfer_result = bus->msgs_index + 1;
complete(&bus->cmd_complete);
out_no_complete:
- return irq_handled;
+ 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;
}
static irqreturn_t aspeed_i2c_bus_irq(int irq, void *dev_id)
{
struct aspeed_i2c_bus *bus = dev_id;
- u32 irq_received, irq_remaining, irq_handled;
+ bool ret;
spin_lock(&bus->lock);
- irq_received = readl(bus->base + ASPEED_I2C_INTR_STS_REG);
- irq_remaining = irq_received;
#if IS_ENABLED(CONFIG_I2C_SLAVE)
- /*
- * In most cases, interrupt bits will be set one by one, although
- * multiple interrupt bits could be set at the same time. It's also
- * possible that master interrupt bits could be set along with slave
- * interrupt bits. Each case needs to be handled using corresponding
- * handlers depending on the current state.
- */
- if (bus->master_state != ASPEED_I2C_MASTER_INACTIVE) {
- irq_handled = aspeed_i2c_master_irq(bus, irq_remaining);
- irq_remaining &= ~irq_handled;
- if (irq_remaining)
- irq_handled |= aspeed_i2c_slave_irq(bus, irq_remaining);
- } else {
- irq_handled = aspeed_i2c_slave_irq(bus, irq_remaining);
- irq_remaining &= ~irq_handled;
- if (irq_remaining)
- irq_handled |= aspeed_i2c_master_irq(bus,
- irq_remaining);
+ if (aspeed_i2c_slave_irq(bus)) {
+ dev_dbg(bus->dev, "irq handled by slave.\n");
+ ret = true;
+ goto out;
}
-#else
- irq_handled = aspeed_i2c_master_irq(bus, irq_remaining);
#endif /* CONFIG_I2C_SLAVE */
- irq_remaining &= ~irq_handled;
- if (irq_remaining)
- dev_err(bus->dev,
- "irq handled != irq. expected 0x%08x, but was 0x%08x\n",
- irq_received, irq_handled);
+ ret = aspeed_i2c_master_irq(bus);
- /* Ack all interrupt bits. */
- writel(irq_received, bus->base + ASPEED_I2C_INTR_STS_REG);
+out:
spin_unlock(&bus->lock);
- return irq_remaining ? IRQ_NONE : IRQ_HANDLED;
+ return ret ? IRQ_HANDLED : IRQ_NONE;
}
static int aspeed_i2c_master_xfer(struct i2c_adapter *adap,
--
2.18.0
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