Re: [PATCH] serial: 8250_bcm7271: Fix arbitration handling

[Florian Fainelli]

On 3/9/23 11:02, Doug Berger wrote:
> The arbitration of the UART DMA is mishandled for a few
> exceptional cases when probing and releasing the driver.
>
> It is possible that the DMA register spaces are not defined in
> device tree for an instance of the driver, so attempts to access
> the registers in brcmuart_arbitration() would use NULL pointers.
>
> It is also possible for the probe function to return an error
> while still holding the UART DMA. This would prevent the UART
> DMA from being claimed by an instance that could use it.
>
> These errors are addressed by only releasing the UART DMA if it
> is held by this instance (i.e. priv->dma_enabled == 1) and
> directing early error paths in probe to this common release_dma
> handling.
>
> Fixes: 41a469482de2 ("serial: 8250: Add new 8250-core based Broadcom STB driver")
> Signed-off-by: Doug Berger <opendmb@xxxxxxxxx>

Acked-by: Florian Fainelli <f.fainelli@xxxxxxxxx>
--
Florian