Re: [PATCH v3 0/2] i2c: imx: fix SMBus block-read of 0 locking the bus

From: Andi Shyti

Date: Thu Jul 16 2026 - 11:41:41 EST


On Tue, Jul 14, 2026 at 05:45:31PM +0200, Wolfram Sang wrote:
> On Mon, Jul 13, 2026 at 08:11:58PM +0200, Vincent Jardin wrote:
> > i2c-imx rejects an SMBus Block Read byte count of 0 (valid per SMBus 3.1
> > 6.5.7) as -EPROTO and returns without emitting a NACK + STOP, leaving the
> > target holding SDA so the bus stays stuck until a power cycle.
>
> Bigger picture: Linux does not support SMBus3 which also allows byte
> counts of up to 255. I started sketching support for all that but could
> never implement it.

Yeah... I have claimed many times to have patches that add
support to smbus3. I also promised many times that I should
update and send them over :-)

Andi

> That being said, despite no SMBus3 support, it should not hang the bus
> like here.