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| author | Marek Behún <kabel@kernel.org> | 2021-04-08 04:00:00 +0200 |
|---|---|---|
| committer | Wolfram Sang <wsa@kernel.org> | 2021-04-15 22:13:19 +0200 |
| commit | 39930213e7779b9c4257499972b8afb8858f1a2d (patch) | |
| tree | 39feba35d1d635c23526d99c5bc634110d77ee54 /drivers/mailbox/stm32-ipcc.c | |
| parent | d434405aaab7d0ebc516b68a8fc4100922d7f5ef (diff) | |
i2c: mv64xxx: Fix random system lock caused by runtime PM
I noticed a weird bug with this driver on Marvell CN9130 Customer
Reference Board.
Sometime after boot, the system locks with the following message:
[104.071363] i2c i2c-0: mv64xxx: I2C bus locked, block: 1, time_left: 0
The system does not respond afterwards, only warns about RCU stalls.
This first appeared with commit e5c02cf54154 ("i2c: mv64xxx: Add runtime
PM support").
With further experimentation I discovered that adding a delay into
mv64xxx_i2c_hw_init() fixes this issue. This function is called before
every xfer, due to how runtime PM works in this driver. It seems that in
order to work correctly, a delay is needed after the bus is reset in
this function.
Since there already is a known erratum with this controller needing a
delay, I assume that this is just another place this needs to be
applied. Therefore I apply the delay only if errata_delay is true.
Signed-off-by: Marek Behún <kabel@kernel.org>
Acked-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Reviewed-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Wolfram Sang <wsa@kernel.org>
Diffstat (limited to 'drivers/mailbox/stm32-ipcc.c')
0 files changed, 0 insertions, 0 deletions