Re: [PATCH 4/8] usb: typec: mux: Find the muxes by also matching against the device node

From: Andy Shevchenko
Date: Mon Jan 28 2019 - 04:54:08 EST


On Fri, Jan 25, 2019 at 3:17 PM Heikki Krogerus
<heikki.krogerus@xxxxxxxxxxxxxxx> wrote:
>
> When the connections are defined in firmware, struct
> device_connection will have the fwnode member pointing to
> the device node (struct fwnode_handle) of the requested
> device, and the endpoint will not be used at all in that
> case.

> static void *typec_mux_match(struct device_connection *con, int ep, void *data)
> {
> + const struct typec_altmode_desc *desc = data;
> struct typec_mux *mux;

> + bool match = !con->id;

I don't see how this assignment is used.

> + size_t nval;
> + u16 *val;
> + int i;
> +
> + if (!con->fwnode) {
> + list_for_each_entry(mux, &mux_list, entry)
> + if (!strcmp(con->endpoint[ep], dev_name(mux->dev)))
> + return mux;
> + return ERR_PTR(-EPROBE_DEFER);
> + }
> +
> + if (match)
> + goto find_mux;
> +
> + /* Accessory Mode muxes */
> + if (!desc) {
> + match = fwnode_property_present(con->fwnode, "accessory");
> + if (match)
> + goto find_mux;
> + return NULL;
> + }
> +
> + /* Alternate Mode muxes */
> + nval = fwnode_property_read_u16_array(con->fwnode, "svid", NULL, 0);
> + if (nval <= 0)
> + return NULL;
> +
> + val = kcalloc(nval, sizeof(*val), GFP_KERNEL);
> + if (!val)
> + return ERR_PTR(-ENOMEM);
> +
> + nval = fwnode_property_read_u16_array(con->fwnode, "svid", val, nval);
> + if (nval < 0) {
> + kfree(val);
> + return ERR_PTR(nval);
> + }
> +
> + for (i = 0; i < nval; i++) {
> + match = val[i] == desc->svid;
> + if (match) {
> + kfree(val);
> + goto find_mux;
> + }
> + }
> + kfree(val);
> + return NULL;
>
> +find_mux:
> list_for_each_entry(mux, &mux_list, entry)
> - if (!strcmp(con->endpoint[ep], dev_name(mux->dev)))
> + if (dev_fwnode(mux->dev) == con->fwnode)
> return mux;
>
> - /*
> - * We only get called if a connection was found, tell the caller to
> - * wait for the switch to show up.
> - */
> - return ERR_PTR(-EPROBE_DEFER);
> + return match ? ERR_PTR(-EPROBE_DEFER) : NULL;
> }

--
With Best Regards,
Andy Shevchenko