src/drivers/usb/gadget.c

/*
 * This file is part of the coreboot project.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
 */

#include <stddef.h>
#include <console/console.h>

#include "ehci_debug.h"
#include "usb_ch9.h"
#include "ehci.h"


#define USB_HUB_PORT_CONNECTION		0
#define USB_HUB_PORT_ENABLED		1
#define USB_HUB_PORT_RESET		4
#define USB_HUB_PORT_POWER		8
#define USB_HUB_C_PORT_CONNECTION	16
#define USB_HUB_C_PORT_RESET		20


static int hub_port_status(const char * buf, int feature)
{
	return !!(buf[feature>>3] & (1<<(feature&0x7)));
}

/* After USB port reset, treat device number 0 as an USB hub. Assign it with
 * a device number hub_addr. Then apply enable and reset on downstream port.
 */
 static int dbgp_hub_enable(struct ehci_dbg_port *ehci_debug, unsigned char hub_addr,
	unsigned char port)
{
	char status[8];
	int ret, loop;

	/* Assign a devicenumber for the hub. */
	ret = dbgp_control_msg(ehci_debug, 0,
		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
		USB_REQ_SET_ADDRESS, hub_addr, 0, NULL, 0);
	if (ret < 0)
		goto err;

	/* Enter configured state on hub. */
	ret = dbgp_control_msg(ehci_debug, hub_addr,
		USB_DIR_OUT | USB_TYPE_STANDARD | USB_RECIP_DEVICE,
		USB_REQ_SET_CONFIGURATION, 1, 0, NULL, 0);
	if (ret < 0)
		goto err;

	/* Set PORT_POWER, poll for PORT_CONNECTION. */
	ret = dbgp_control_msg(ehci_debug, hub_addr,
		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER,
		USB_REQ_SET_FEATURE, USB_HUB_PORT_POWER, port, NULL, 0);
	if (ret < 0)
		goto err;

	loop = 100;
	do {
		dbgp_mdelay(10);
		ret = dbgp_control_msg(ehci_debug, hub_addr,
			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_OTHER,
			USB_REQ_GET_STATUS, 0, port, status, 4);
		if (ret < 0)
			goto err;
		if (hub_port_status(status, USB_HUB_PORT_CONNECTION))
			break;
	} while (--loop);
	if (! loop)
		goto err;

	ret = dbgp_control_msg(ehci_debug, hub_addr,
		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER,
		USB_REQ_CLEAR_FEATURE, USB_HUB_C_PORT_CONNECTION, port, NULL, 0);
	if (ret < 0)
		goto err;


	/* Set PORT_RESET, poll for C_PORT_RESET. */
	ret = dbgp_control_msg(ehci_debug, hub_addr,
		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER,
		USB_REQ_SET_FEATURE, USB_HUB_PORT_RESET, port, NULL, 0);
	if (ret < 0)
		goto err;

	loop = 100;
	do {
		dbgp_mdelay(10);
		ret = dbgp_control_msg(ehci_debug, hub_addr,
			USB_DIR_IN | USB_TYPE_CLASS | USB_RECIP_OTHER,
			USB_REQ_GET_STATUS, 0, port, status, 4);
		if (ret < 0)
			goto err;
		if (hub_port_status(status, USB_HUB_C_PORT_RESET))
			break;
	} while (--loop);
	if (! loop)
		goto err;

	ret = dbgp_control_msg(ehci_debug, hub_addr,
		USB_DIR_OUT | USB_TYPE_CLASS | USB_RECIP_OTHER,
		USB_REQ_CLEAR_FEATURE, USB_HUB_C_PORT_RESET, port, NULL, 0);
	if (ret < 0)
		goto err;

	if (hub_port_status(status, USB_HUB_PORT_ENABLED))
		return 0;
err:
	return -1;
}


int dbgp_probe_gadget(struct ehci_dbg_port *ehci_debug, struct dbgp_pipe *pipe)
{
	int ret;

	if (CONFIG_USBDEBUG_OPTIONAL_HUB_PORT != 0) {
		ret = dbgp_hub_enable(ehci_debug, USB_DEBUG_DEVNUM-1,
			CONFIG_USBDEBUG_OPTIONAL_HUB_PORT);
		if (ret < 0) {
			printk(BIOS_INFO, "Could not enable USB hub on debug port.\n");
			return ret;
		}
	}

	return 0;
}