Re: [PATCH v6 5/7] drm/bridge: anx7625: Register Type C mode switches

From: Andy Shevchenko
Date: Thu Nov 24 2022 - 07:18:20 EST


On Thu, Nov 24, 2022 at 06:20:54PM +0800, Pin-yen Lin wrote:
> Register USB Type-C mode switches when the "mode-switch" property and
> relevant port are available in Device Tree. Configure the crosspoint
> switch based on the entered alternate mode for a specific Type-C
> connector.

...

> +static void anx7625_typec_two_ports_update(struct anx7625_data *ctx)
> +{
> + if (ctx->typec_ports[0].dp_connected && ctx->typec_ports[1].dp_connected)
> + /* Both ports available, do nothing to retain the current one. */
> + return;

> + else if (ctx->typec_ports[0].dp_connected)

This 'else' is redundant. I would rewrite above as

/* Check if both ports available and do nothing to retain the current one */
if (ctx->typec_ports[0].dp_connected && ctx->typec_ports[1].dp_connected)
return;

if (ctx->typec_ports[0].dp_connected)

> + anx7625_set_crosspoint_switch(ctx, TYPEC_ORIENTATION_NORMAL);
> + else if (ctx->typec_ports[1].dp_connected)
> + anx7625_set_crosspoint_switch(ctx, TYPEC_ORIENTATION_REVERSE);
> +}

...

> + data->dp_connected = (state->alt && state->alt->svid == USB_TYPEC_DP_SID &&
> + state->alt->mode == USB_TYPEC_DP_MODE);

Parentheses are not needed.

...

> + /*
> + * <0 1> refers to SSRX1/SSTX1, and <2 3> refers to SSRX2/SSTX2.
> + */
> + for (i = 0; i < num_lanes; i++) {

> + if (port_num != -1 && port_num != dp_lanes[i] / 2) {
> + dev_err(dev, "Invalid data lane numbers\n");
> + return -EINVAL;
> + }

According to Rob Linux must not validate device tree. If you need it, use
proper YAML schema.

> + port_num = dp_lanes[i] / 2;
> + }

...

> + if (!ctx->num_typec_switches) {
> + dev_warn(dev, "No Type-C switches node found\n");

> + return ret;

Why not to return 0 explicitly?

> + }

...

> + ctx->typec_ports = devm_kcalloc(

Broken indentation.

> + dev, ctx->num_typec_switches, sizeof(struct anx7625_port_data),
> + GFP_KERNEL);
> + if (!ctx->typec_ports)
> + return -ENOMEM;

...

> +struct anx7625_port_data {

> + bool dp_connected;

You can save some bytes on some architectures if move this to be last field.

> + struct typec_mux_dev *typec_mux;
> + struct anx7625_data *ctx;
> +};

--
With Best Regards,
Andy Shevchenko