[PATCH v1 2/9] mailbox: Add NVIDIA Tegra XUSB mailbox driver

[Andrew Bresticker]

On Wed, Jun 25, 2014 at 3:02 PM, Stephen Warren <swarren at wwwdotorg.org> wrote:
> On 06/18/2014 12:16 AM, Andrew Bresticker wrote:
>> The Tegra XHCI controller communicates requests to the host through
>> a mailbox interface.  Host drivers which can handle these requests,
>> such as the Tegra XUSB pad controller driver and upcoming Tegra XHCI
>> host controller driver, can send messages and register to be notified
>> of incoming messages.
>
>> diff --git a/include/linux/tegra-xusb-mbox.h b/include/linux/tegra-xusb-mbox.h
>
>> +extern int tegra_xusb_mbox_register_notifier(struct tegra_xusb_mbox *mbox,
>> +                                          struct notifier_block *nb);
>> +extern void tegra_xusb_mbox_unregister_notifier(struct tegra_xusb_mbox *mbox,
>> +                                             struct notifier_block *nb);
>> +extern int tegra_xusb_mbox_send(struct tegra_xusb_mbox *mbox,
>> +                             enum tegra_xusb_mbox_cmd cmd, u32 data);
>> +extern struct tegra_xusb_mbox *
>> +tegra_xusb_mbox_lookup_by_phandle(struct device_node *np, const char *prop);
>
> This seems to use a custom API. I've seen mention of a mailbox
> subsystem, and I assume that has a standardized API. Should this driver
> implement that instead?

All the mailbox drivers currently use a custom API, but there is
indeed a patch series floating around to create a generic mailbox
framework, though it hasn't landed in -next yet.  I can take a look at
how this driver would fit into that framework.