[PATCH v3 3/7] board: rock5b-rk3588: add USB-C controller support

[Jonas Karlman]

Hi Sebastian,

On 2024-08-02 19:59, Sebastian Reichel wrote:
> Enable support for the fusb302 USB Type-C controller.
> 
> This will do early USB PD (power deliver) negotiation, which must happen
> within 5 seconds after the USB-C connector has plugged in according to
> the specification. It takes almost 5 seconds to go through the bootchain
> on Rock 5B and jump to the operating system. When the Linux initializes
> the fusb302 usually 20-30 seconds have gone since the device has been
> plugged, which is far too late. The USB PD power source reacts with a
> hard reset, which disables VBUS for some time. This is not a problem for
> a battery driven device, but Rock 5B will loose its power-supply and
> reset. By initializing PD in U-Boot, this can be avoided.
> 
> Signed-off-by: Sebastian Reichel <sebastian.reichel at collabora.com>
> ---
>  board/radxa/rock5b-rk3588/Makefile        |  6 ++++
>  board/radxa/rock5b-rk3588/rock5b-rk3588.c | 35 +++++++++++++++++++++++
>  2 files changed, 41 insertions(+)
>  create mode 100644 board/radxa/rock5b-rk3588/Makefile
>  create mode 100644 board/radxa/rock5b-rk3588/rock5b-rk3588.c
> 
> diff --git a/board/radxa/rock5b-rk3588/Makefile b/board/radxa/rock5b-rk3588/Makefile
> new file mode 100644
> index 000000000000..95d813596da4
> --- /dev/null
> +++ b/board/radxa/rock5b-rk3588/Makefile
> @@ -0,0 +1,6 @@
> +# SPDX-License-Identifier:     GPL-2.0+
> +#
> +# Copyright (c) 2022 Collabora Ltd.
> +#
> +
> +obj-y += rock5b-rk3588.o
> diff --git a/board/radxa/rock5b-rk3588/rock5b-rk3588.c b/board/radxa/rock5b-rk3588/rock5b-rk3588.c
> new file mode 100644
> index 000000000000..1c17ae93c76c
> --- /dev/null
> +++ b/board/radxa/rock5b-rk3588/rock5b-rk3588.c
> @@ -0,0 +1,35 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) 2023-2024 Collabora Ltd.
> + */
> +
> +#include <usb/tcpm.h>
> +
> +#ifdef CONFIG_MISC_INIT_R
> +int misc_init_r(void)

You should not override misc_init_r() here as it will override the
rockchip board common misc_init_r() function that read cpuid, set serial
and ethernet mac address env vars.

I would suggest you instead of tcpm_get() add something similar to

int tcpm_probe_all()
{
	struct udevice *dev;
	struct uclass *uc;
	int ret;

	ret = uclass_get(UCLASS_TCPM, &uc);
	if (ret)
		return ret;

	for (ret = uclass_first_device_check(UCLASS_TCPM, &dev);
	     dev;
	     ret = uclass_next_device_check(&dev)) {
		if (ret)
			printf("Failed to probe Type-C controller '%s' (ret=%d)\n",
			       dev->name, ret);
	}

	return 0;
}

or if we do not care about the error message this could use

	uclass_probe_all(UCLASS_TCPM);

and call it from the rockchip board common code in mach-rockchip/board.c
directly after the call to regulators_enable_boot_on() in board_init().

Alternatively you could call following in a tcpm_post_bind()

	dev_or_flags(dev, DM_FLAG_PROBE_AFTER_BIND);

to automatically probe the device as soon as possible after all devices
have been bind, this is how the rockchip-io-domain driver does it.

Otherwise we need to add custom board code for each board using USB PD,
something to avoid.

Regards,
Jonas

> +{
> +	struct udevice *dev;
> +	int ret;
> +
> +	/*
> +	 * This will do early USB PD (power deliver) negotiation, which must
> +	 * happen within 5 seconds after the USB-C connector has plugged in
> +	 * according to the specification. It takes almost 5 seconds to go
> +	 * through the bootchain on Rock 5B and jump to the operating system.
> +	 * When the Linux initializes the fusb302 usually 20-30 seconds have
> +	 * gone since the device has been plugged, which is far too late.
> +	 *
> +	 * The USB PD power source reacts with a hard reset, which disables
> +	 * VBUS for some time. This is not a problem for a battery driven
> +	 * device, but Rock 5B will loose its power-supply and reset. By
> +	 * initializing PD in U-Boot, this can be avoided.
> +	 */
> +	ret = tcpm_get("usb-typec at 22", &dev);
> +	if (ret) {
> +		printf("Failed to probe Type-C controller\n");
> +		return 0;
> +	}
> +
> +	return 0;
> +}
> +#endif