Re: [net-next RFC PATCH 1/4] net: dsa: qca8k: drop qca8k_read/write/rmw for regmap variant

[Christian Marangi <ansuelsmth@gmail.com>]

On Tue, Jul 19, 2022 at 02:43:58AM +0300, Vladimir Oltean wrote:
> On Mon, Jul 18, 2022 at 11:54:44PM +0200, Christian Marangi wrote:
> > On Mon, Jul 18, 2022 at 11:30:42PM +0300, Vladimir Oltean wrote:
> > > On Mon, Jul 18, 2022 at 09:30:58PM +0200, Christian Marangi wrote:
> > > > Tell me if I got this wrong.
> > > > 
> > > > The suggestion was to move the struct dsa_switch_ops to qca8k.h and add
> > > > in the specific code probe the needed ops to add to the generic
> > > > struct...
> > > 
> > > The declaration yes; the definition to qca8k-common.c. See for example
> > > where felix_switch_ops is, relative to felix_vsc9959.c, seville_vsc9953.c
> > > (users), felix.h (declaration), and felix.c (definition). Or how
> > > mv88e6xxx_switch_ops does things and still supports a gazillion of switches.
> > 
> > Mhh I checked the example and they doesn't seems to be useful from my
> > problem. But I think it's better to discuss this to the patch directly
> > so you can better understand whay I intended with having dsa_switch_ops
> > set to const.
> 
> So you don't modify the common dsa_switch_ops from the switch-specific
> probe path, but rather, from the common dsa_switch_ops method, you call
> a second function pointer.
> 
> static void felix_phylink_validate(struct dsa_switch *ds, int port,
> 				   unsigned long *supported,
> 				   struct phylink_link_state *state)
> {
> 	struct ocelot *ocelot = ds->priv;
> 	struct felix *felix = ocelot_to_felix(ocelot);
> 
> 	if (felix->info->phylink_validate)
> 		felix->info->phylink_validate(ocelot, port, supported, state);
> }

Ohhh ok now it makes sense.

If the ops is not supported should I return -ENOSUPP?
Example some ops won't be supported like the get_phy_flags or
connect_tag_protocol for example.

Anyway the series is ready, I was just pushing it... At the end it's 23
patch big... (I know you will hate me but at least it's reviewable)

My solution currently was this...

	ops = devm_kzalloc(&mdiodev->dev, sizeof(*ops), GFP_KERNEL);
	if (!ops)
		return -ENOMEM;

	/* Copy common ops */
	memcpy(ops, &qca8k_switch_ops, sizeof(*ops));

	/* Setup specific ops */
	ops->get_tag_protocol = qca8k_get_tag_protocol;
	ops->setup = qca8k_setup;
	ops->phylink_get_caps = qca8k_phylink_get_caps;
	ops->phylink_mac_select_pcs = qca8k_phylink_mac_select_pcs;
	ops->phylink_mac_config = qca8k_phylink_mac_config;
	ops->phylink_mac_link_down = qca8k_phylink_mac_link_down;
	ops->phylink_mac_link_up = qca8k_phylink_mac_link_up;
	ops->get_phy_flags = qca8k_get_phy_flags;
	ops->master_state_change = qca8k_master_change;
	ops->connect_tag_protocol = qca8k_connect_tag_protocol;

	/* Assign the final ops */
	priv->ds->ops = ops;

Will wait your response on how to hanle ops that are not supported.
(I assume dsa checks if an ops is declared and not if it does return
ENOSUPP, so this is my concern your example)

-- 
	Ansuel