Re: [PATCH 2/3] soc: renesas: Add Renesas R-Car MFIS driver

Jassi Brar
2026-03-29T17:05:48Z

On Tue, Mar 17, 2026 at 8:06 AM Wolfram Sang
<wsa+renesas@sang-engineering.com> wrote:
>
> Renesas R-Car MFIS offers multiple features but most importantly
> mailboxes and hwspinlocks. Because they share a common register space
> and a common register unprotection mechanism, a single driver was chosen
> to handle all dependencies. (MFD and auxiliary bus have been tried as
> well, but they failed because of circular dependencies.)
>
> In this first step, the driver implements common register access and a
> mailbox controller. hwspinlock support will be added incrementally, once
> the subsystem allows out-of-directory drivers.
>
> Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
> ---
>
The mailbox part seems reasonable to me, apart from the nits already
pointed out.
Acked-by: Jassi Brar <jassisinghbrar@gmail.com>