[PATCH v4 21/28] net: wan: Add framer framework support

[Simon Horman]

On Fri, Aug 18, 2023 at 06:39:15PM +0200, Christophe Leroy wrote:
> From: Herve Codina <herve.codina at bootlin.com>
> 
> A framer is a component in charge of an E1/T1 line interface.
> Connected usually to a TDM bus, it converts TDM frames to/from E1/T1
> frames. It also provides information related to the E1/T1 line.
> 
> The framer framework provides a set of APIs for the framer drivers
> (framer provider) to create/destroy a framer and APIs for the framer
> users (framer consumer) to obtain a reference to the framer, and
> use the framer.
> 
> This basic implementation provides a framer abstraction for:
>  - power on/off the framer
>  - get the framer status (line state)
>  - be notified on framer status changes
>  - get/set the framer configuration
> 
> Signed-off-by: Herve Codina <herve.codina at bootlin.com>
> Reviewed-by: Christophe Leroy <christophe.leroy at csgroup.eu>
> Signed-off-by: Christophe Leroy <christophe.leroy at csgroup.eu>

Hi Christophe and Herve,

some minor feedback from my side.

...

> diff --git a/drivers/net/wan/framer/framer-core.c b/drivers/net/wan/framer/framer-core.c

...

> +/**
> + * framer_create() - create a new framer
> + * @dev: device that is creating the new framer
> + * @node: device node of the framer. default to dev->of_node.
> + * @ops: function pointers for performing framer operations
> + *
> + * Called to create a framer using framer framework.
> + */
> +struct framer *framer_create(struct device *dev, struct device_node *node,
> +			     const struct framer_ops *ops)
> +{
> +	int ret;
> +	int id;
> +	struct framer *framer;

Please arrange local variable declarations for Networking code
using reverse xmas tree order - longest line to shortest.

https://github.com/ecree-solarflare/xmastree is helpful here.

...

> diff --git a/include/linux/framer/framer-provider.h b/include/linux/framer/framer-provider.h

...

> +/**
> + * struct framer_ops - set of function pointers for performing framer operations
> + * @init: operation to be performed for initializing the framer
> + * @exit: operation to be performed while exiting
> + * @power_on: powering on the framer
> + * @power_off: powering off the framer
> + * @flags: OR-ed flags (FRAMER_FLAG_*) to ask for core functionality
> + *          - @FRAMER_FLAG_POLL_STATUS:
> + *            Ask the core to perfom a polling to get the framer status and

nit: perfom -> perform

     checkpatch.pl --codespell is your friend here

> + *            notify consumers on change.
> + *            The framer should call @framer_notify_status_change() when it
> + *            detects a status change. This is usally done using interrutps.

nit: usally -> usually
     interrutps -> interrupts

...

> diff --git a/include/linux/framer/framer.h b/include/linux/framer/framer.h
> new file mode 100644
> index 000000000000..0bee7135142f
> --- /dev/null
> +++ b/include/linux/framer/framer.h
> @@ -0,0 +1,199 @@
> +/* SPDX-License-Identifier: GPL-2.0-or-later */
> +/*
> + * Generic framer header file
> + *
> + * Copyright 2023 CS GROUP France
> + *
> + * Author: Herve Codina <herve.codina at bootlin.com>
> + */
> +
> +#ifndef __DRIVERS_FRAMER_H
> +#define __DRIVERS_FRAMER_H
> +
> +#include <linux/err.h>
> +#include <linux/mutex.h>
> +#include <linux/notifier.h>
> +#include <linux/of.h>
> +#include <linux/device.h>
> +#include <linux/workqueue.h>
> +
> +/**
> + * enum framer_iface - Framer interface

As this is a kernel-doc, please include documentation for
the defined constants: FRAMER_IFACE_E1 and FRAMER_IFACE_T1.

As flagged by: ./scripts/kernel-doc -none

> + */
> +enum framer_iface {
> +	FRAMER_IFACE_E1,      /* E1 interface */
> +	FRAMER_IFACE_T1,      /* T1 interface */
> +};
> +
> +/**
> + * enum framer_clock_mode - Framer clock mode

Likewise here too.

Also, nit: framer_clock_mode -> framer_clock_type

> + */
> +enum framer_clock_type {
> +	FRAMER_CLOCK_EXT, /* External clock */
> +	FRAMER_CLOCK_INT, /* Internal clock */
> +};
> +
> +/**
> + * struct framer_configuration - Framer configuration

nit: framer_configuration -> framer_config

> + * @line_iface: Framer line interface
> + * @clock_mode: Framer clock type
> + * @clock_rate: Framer clock rate
> + */
> +struct framer_config {
> +	enum framer_iface iface;
> +	enum framer_clock_type clock_type;
> +	unsigned long line_clock_rate;
> +};
> +
> +/**
> + * struct framer_status - Framer status
> + * @link_is_on: Framer link state. true, the link is on, false, the link is off.
> + */
> +struct framer_status {
> +	bool link_is_on;
> +};
> +
> +/**
> + * framer_event - event available for notification

nit: framer_event -> enum framer_event

A~d please document FRAMER_EVENT_STATUS in the kernel doc too.

> + */
> +enum framer_event {
> +	FRAMER_EVENT_STATUS,	/* Event notified on framer_status changes */
> +};

...