Hi Tao,
On 10/8/2019 3:00 PM, Tao Ren wrote:
On 10/7/19 4:13 PM, Jae Hyun Yoo wrote:
In case of master pending state, it should not trigger the master
command because this H/W is sharing the same data buffer for slave
and master operations, so this commit fixes the issue with making
the master command triggering happen when the state goes to active
state.
Signed-off-by: Jae Hyun Yoo <jae.hyun.yoo@xxxxxxxxxxxxxxx>
---
drivers/i2c/busses/i2c-aspeed.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index fa66951b05d0..40f6cf98d32e 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -336,18 +336,19 @@ static void aspeed_i2c_do_start(struct aspeed_i2c_bus *bus)
struct i2c_msg *msg = &bus->msgs[bus->msgs_index];
u8 slave_addr = i2c_8bit_addr_from_msg(msg);
- bus->master_state = ASPEED_I2C_MASTER_START;
-
#if IS_ENABLED(CONFIG_I2C_SLAVE)
/*
* If it's requested in the middle of a slave session, set the master
* state to 'pending' then H/W will continue handling this master
* command when the bus comes back to the idle state.
*/
- if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE)
+ if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE) {
bus->master_state = ASPEED_I2C_MASTER_PENDING;
+ return;
+ }
#endif /* CONFIG_I2C_SLAVE */
+ bus->master_state = ASPEED_I2C_MASTER_START;
bus->buf_index = 0;
if (msg->flags & I2C_M_RD) {
@@ -432,7 +433,7 @@ static u32 aspeed_i2c_master_irq(struct aspeed_i2c_bus *bus, u32 irq_status)
if (bus->slave_state != ASPEED_I2C_SLAVE_INACTIVE)
goto out_no_complete;
- bus->master_state = ASPEED_I2C_MASTER_START;
+ aspeed_i2c_do_start(bus);
}
Shall we move the restart-master logic from master_irq to bus_irq? The reason being:
master transaction cannot be restarted when aspeed-i2c is running in slave state and
receives STOP interrupt, because aspeed_i2c_master_irq won't be called in this case.
Even in that case, master can be restarted properly because slave_irq
will be called first because master is in MASTER_PENDING state, so the
slave_irq handles the STOP interrupt as well, and then master_irq will
be called with SLAVE_INACTIVE state so the aspeed_i2c_do_start can be
called eventually.
Also, this is right point to call the aspeed_i2c_do_start
because master state will be changed to MASTER_START by the
aspeed_i2c_do_start and we have to do remaining handling for the
MASTER_START in the master_irq by falling through after the call.
Thanks,
Jae
