Hi
On 8/16/22 05:51, wolfgang9277@xxxxxxx wrote:
From: wolfgang huang <huangjinhui@xxxxxxxxxxx>
bind two or more slave devices to master device.
What does this sentence mean?
while master device is process reading, dev->msgs
used as a buffer to process the read data,
while the other device uses i2c_dw_xfer to read/write,
this will directly change dev->msgs, causing the
first device reading process to crash or other confusion.
so we should to check the device status before modifying
dev->msgs and others.
[ 1244.815334] i2c_dw_isr+0x2c8/0x5e0
[ 1244.819238] __handle_irq_event_percpu+0x5c/0x168
[ 1244.824350] handle_irq_event_percpu+0x1c/0x58
[ 1244.829201] handle_irq_event+0x40/0xa0
[ 1244.833449] handle_fasteoi_irq+0xcc/0x1b0
[ 1244.837956] generic_handle_irq+0x24/0x38
[ 1244.842376] __handle_domain_irq+0x5c/0xb8
[ 1244.846883] gic_handle_irq+0x94/0x1c8
[ 1244.851043] el1_irq+0xb8/0x140
[ 1244.854599] arch_cpu_idle+0x10/0x18
[ 1244.858588] do_idle+0x19c/0x260
[ 1244.862231] cpu_startup_entry+0x20/0x28
I would like to understand this more. Like is the bus not busy wait move
enough or if it's just masking the issue away.
Are you able to share what kind of setup you have and do you know how to
trigger this or does it occur randomly during run?
Signed-off-by: wolfgang huang <huangjinhui@xxxxxxxxxxx>
---
drivers/i2c/busses/i2c-designware-master.c | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)
diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
index 44a94b225ed8..07f7d5e2d12d 100644
--- a/drivers/i2c/busses/i2c-designware-master.c
+++ b/drivers/i2c/busses/i2c-designware-master.c
@@ -557,6 +557,14 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
pm_runtime_get_sync(dev->dev);
+ ret = i2c_dw_acquire_lock(dev);
+ if (ret)
+ goto done_nolock;
+
+ ret = i2c_dw_wait_bus_not_busy(dev);
+ if (ret)
+ goto done;
+
/*
* Initiate I2C message transfer when AMD NAVI GPU card is enabled,
* As it is polling based transfer mechanism, which does not support
Here a few lines below the lock is never released in case of
MODEL_AMD_NAVI_GPU since code goes to "done_nolock" after returning from
amd_i2c_dw_xfer_quirk().
Jarkko
