Re: [PATCH v3 6/8] greybus: Add mikroBUS manifest types

Greg Kroah-Hartman
2024-04-11T12:03:51Z

On Sat, Mar 16, 2024 at 12:19:04AM +0530, Ayush Singh wrote:
> Add data structures for parsing mikroBUS manifests, which are based on
> greybus manifest.
>
> Signed-off-by: Ayush Singh <ayushdevel1325@gmail.com>
> ---
> include/linux/greybus/greybus_manifest.h | 49 ++++++++++++++++++++++++
> 1 file changed, 49 insertions(+)
>
> diff --git a/include/linux/greybus/greybus_manifest.h b/include/linux/greybus/greybus_manifest.h
> index bef9eb2093e9..83241e19d9b3 100644
> --- a/include/linux/greybus/greybus_manifest.h
> +++ b/include/linux/greybus/greybus_manifest.h
> @@ -23,6 +23,9 @@ enum greybus_descriptor_type {
> GREYBUS_TYPE_STRING = 0x02,
> GREYBUS_TYPE_BUNDLE = 0x03,
> GREYBUS_TYPE_CPORT = 0x04,
> + GREYBUS_TYPE_MIKROBUS = 0x05,
> + GREYBUS_TYPE_PROPERTY = 0x06,
> + GREYBUS_TYPE_DEVICE = 0x07,

These need approval in the spec before we can add them here.

And you are adding 3 different things here, not just one. Shouldn't
this be 3 patches?

> };
>
> enum greybus_protocol {
> @@ -151,6 +154,49 @@ struct greybus_descriptor_cport {
> __u8 protocol_id; /* enum greybus_protocol */
> } __packed;
>
> +/*
> + * A mikrobus descriptor is used to describe the details
> + * about the bus ocnfiguration for the add-on board
> + * connected to the mikrobus port.
> + */
> +struct greybus_descriptor_mikrobus {
> + __u8 pin_state[12];
> +} __packed;
> +
> +/*
> + * A property descriptor is used to pass named properties
> + * to device drivers through the unified device properties
> + * interface under linux/property.h
> + */
> +struct greybus_descriptor_property {
> + __u8 length;
> + __u8 id;
> + __u8 propname_stringid;
> + __u8 type;
> + __u8 value[];

Don't we have a "counted-by" marking that we can use to show how big
value[] here is?

> +} __packed;
> +
> +/*
> + * A device descriptor is used to describe the
> + * details required by a add-on board device
> + * driver.
> + */
> +struct greybus_descriptor_device {
> + __u8 id;
> + __u8 driver_stringid;
> + __u8 protocol;
> + __u8 reg;
> + __le32 max_speed_hz;
> + __u8 irq;
> + __u8 irq_type;
> + __u8 mode;
> + __u8 prop_link;
> + __u8 gpio_link;
> + __u8 reg_link;
> + __u8 clock_link;
> + __u8 pad[1];

Why the padding?

And this looks like a greybus thing, not a mikrobus thing, right? Some
description of exactly what this is and what it does would be good.

thanks,

greg k-h