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path: root/payloads/libpayload/drivers/usb/usb.c
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/*
 *
 * Copyright (C) 2008-2010 coresystems GmbH
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

//#define USB_DEBUG

#include <libpayload-config.h>
#include <usb/usb.h>

#define DR_DESC gen_bmRequestType(device_to_host, standard_type, dev_recp)

hci_t *usb_hcs = 0;

hci_t *
new_controller (void)
{
	hci_t *controller = xzalloc(sizeof (hci_t));
	controller->next = usb_hcs;
	usb_hcs = controller;
	return controller;
}

void
detach_controller (hci_t *controller)
{
	if (controller == NULL)
		return;

	usb_detach_device(controller, 0);	/* tear down root hub tree */

	if (usb_hcs == controller) {
		usb_hcs = controller->next;
	} else {
		hci_t *it = usb_hcs;
		while (it != NULL) {
			if (it->next == controller) {
				it->next = controller->next;
				return;
			}
			it = it->next;
		}
	}
}

/**
 * Shut down all controllers
 */
int
usb_exit (void)
{
	while (usb_hcs != NULL) {
		usb_hcs->shutdown(usb_hcs);
	}
	return 0;
}

/**
 * Polls all hubs on all USB controllers, to find out about device changes
 */
void
usb_poll (void)
{
	if (usb_hcs == 0)
		return;

	if (usb_poll_prepare)
		usb_poll_prepare();

	hci_t *controller = usb_hcs;
	while (controller != NULL) {
		int i;
		for (i = 0; i < 128; i++) {
			if (controller->devices[i] != 0) {
				controller->devices[i]->poll (controller->devices[i]);
			}
		}
		controller = controller->next;
	}
}

usbdev_t *
init_device_entry (hci_t *controller, int i)
{
	usbdev_t *dev = calloc(1, sizeof(usbdev_t));
	if (!dev) {
		usb_debug("no memory to allocate device structure\n");
		return NULL;
	}
	if (controller->devices[i] != 0)
		usb_debug("warning: device %d reassigned?\n", i);
	controller->devices[i] = dev;
	dev->controller = controller;
	dev->address = -1;
	dev->hub = -1;
	dev->port = -1;
	dev->init = usb_nop_init;
	dev->init (controller->devices[i]);
	return dev;
}

int
set_feature (usbdev_t *dev, int endp, int feature, int rtype)
{
	dev_req_t dr;

	dr.bmRequestType = rtype;
	dr.data_dir = host_to_device;
	dr.bRequest = SET_FEATURE;
	dr.wValue = feature;
	dr.wIndex = endp;
	dr.wLength = 0;

	return dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0);
}

int
get_status (usbdev_t *dev, int intf, int rtype, int len, void *data)
{
	dev_req_t dr;

	dr.bmRequestType = rtype;
	dr.data_dir = device_to_host;
	dr.bRequest = GET_STATUS;
	dr.wValue = 0;
	dr.wIndex = intf;
	dr.wLength = len;

	return dev->controller->control (dev, IN, sizeof (dr), &dr, len, data);
}

/*
 * Certain Lexar / Micron USB 2.0 disks will fail the get_descriptor(DT_CFG)
 * call due to timing issues. Work around this by making extra attempts on
 * failure.
 */
#define GET_DESCRIPTOR_TRIES 3

int
get_descriptor(usbdev_t *dev, int rtype, int desc_type, int desc_idx,
		void *data, size_t len)
{
	dev_req_t dr;
	int fail_tries = 0;
	int ret = 0;

	while (fail_tries++ < GET_DESCRIPTOR_TRIES) {
		dr.bmRequestType = rtype;
		dr.bRequest = GET_DESCRIPTOR;
		dr.wValue = desc_type << 8 | desc_idx;
		dr.wIndex = 0;
		dr.wLength = len;

		ret = dev->controller->control(dev, IN,
				sizeof(dr), &dr, len, data);

		if (ret == len)
			break;
		udelay(10);
	}
	return ret;
}

int
set_configuration (usbdev_t *dev)
{
	dev_req_t dr;

	dr.bmRequestType = 0;
	dr.bRequest = SET_CONFIGURATION;
	dr.wValue = dev->configuration->bConfigurationValue;
	dr.wIndex = 0;
	dr.wLength = 0;

	return dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0);
}

int
clear_feature (usbdev_t *dev, int endp, int feature, int rtype)
{
	dev_req_t dr;

	dr.bmRequestType = rtype;
	dr.data_dir = host_to_device;
	dr.bRequest = CLEAR_FEATURE;
	dr.wValue = feature;
	dr.wIndex = endp;
	dr.wLength = 0;

	return dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0;
}

int
clear_stall (endpoint_t *ep)
{
	int ret = clear_feature (ep->dev, ep->endpoint, ENDPOINT_HALT,
		gen_bmRequestType (host_to_device, standard_type, endp_recp));
	ep->toggle = 0;
	return ret;
}

/* returns free address or -1 */
static int
get_free_address (hci_t *controller)
{
	int i = controller->latest_address + 1;
	for (; i != controller->latest_address; i++) {
		if (i >= ARRAY_SIZE(controller->devices) || i < 1) {
			usb_debug("WARNING: Device addresses for controller %#x"
				  " wrapped around!\n", controller->reg_base);
			i = 0;
			continue;
		}
		if (controller->devices[i] == 0) {
			controller->latest_address = i;
			return i;
		}
	}
	usb_debug ("no free address found\n");
	return -1;		// no free address
}

int
usb_decode_mps0(usb_speed speed, u8 bMaxPacketSize0)
{
	switch (speed) {
	case LOW_SPEED:
		if (bMaxPacketSize0 != 8) {
			usb_debug("Invalid MPS0: 0x%02x\n", bMaxPacketSize0);
			bMaxPacketSize0 = 8;
		}
		return bMaxPacketSize0;
	case FULL_SPEED:
		switch (bMaxPacketSize0) {
		case 8: case 16: case 32: case 64:
			return bMaxPacketSize0;
		default:
			usb_debug("Invalid MPS0: 0x%02x\n", bMaxPacketSize0);
			return 8;
		}
	case HIGH_SPEED:
		if (bMaxPacketSize0 != 64) {
			usb_debug("Invalid MPS0: 0x%02x\n", bMaxPacketSize0);
			bMaxPacketSize0 = 64;
		}
		return bMaxPacketSize0;
	case SUPER_SPEED:
	/* Intentional fallthrough */
	case SUPER_SPEED_PLUS:
		if (bMaxPacketSize0 != 9) {
			usb_debug("Invalid MPS0: 0x%02x\n", bMaxPacketSize0);
			bMaxPacketSize0 = 9;
		}
		return 1 << bMaxPacketSize0;
	default: 	/* GCC is stupid and cannot deal with enums correctly */
		return 8;
	}
}

int speed_to_default_mps(usb_speed speed)
{
	switch (speed) {
	case LOW_SPEED:
		return 8;
	case FULL_SPEED:
	case HIGH_SPEED:
		return 64;
	case SUPER_SPEED:
	/* Intentional fallthrough */
	case SUPER_SPEED_PLUS:
	default:
		return 512;
	}
}

/* Normalize bInterval to log2 of microframes */
static int
usb_decode_interval(usb_speed speed, const endpoint_type type, const unsigned char bInterval)
{
#define LOG2(a) ((sizeof(unsigned) << 3) - __builtin_clz(a) - 1)
	switch (speed) {
	case LOW_SPEED:
		switch (type) {
		case ISOCHRONOUS: case INTERRUPT:
			return LOG2(bInterval) + 3;
		default:
			return 0;
		}
	case FULL_SPEED:
		switch (type) {
		case ISOCHRONOUS:
			return (bInterval - 1) + 3;
		case INTERRUPT:
			return LOG2(bInterval) + 3;
		default:
			return 0;
		}
	case HIGH_SPEED:
		switch (type) {
		case ISOCHRONOUS: case INTERRUPT:
			return bInterval - 1;
		default:
			return LOG2(bInterval);
		}
	case SUPER_SPEED:
	/* Intentional fallthrough */
	case SUPER_SPEED_PLUS:
		switch (type) {
		case ISOCHRONOUS: case INTERRUPT:
			return bInterval - 1;
		default:
			return 0;
		}
	default:
		return 0;
	}
#undef LOG2
}

usbdev_t *
generic_set_address (hci_t *controller, usb_speed speed,
		     int hubport, int hubaddr)
{
	int adr = get_free_address (controller);	// address to set
	if (adr < 0)
		return NULL;
	dev_req_t dr;

	memset (&dr, 0, sizeof (dr));
	dr.data_dir = host_to_device;
	dr.req_type = standard_type;
	dr.req_recp = dev_recp;
	dr.bRequest = SET_ADDRESS;
	dr.wValue = adr;
	dr.wIndex = 0;
	dr.wLength = 0;

	usbdev_t *dev = init_device_entry(controller, adr);
	if (!dev)
		return NULL;

	// dummy values for registering the address
	dev->address = 0;
	dev->hub = hubaddr;
	dev->port = hubport;
	dev->speed = speed;
	dev->endpoints[0].dev = dev;
	dev->endpoints[0].endpoint = 0;
	dev->endpoints[0].maxpacketsize = 8;
	dev->endpoints[0].toggle = 0;
	dev->endpoints[0].direction = SETUP;
	dev->endpoints[0].type = CONTROL;
	if (dev->controller->control (dev, OUT, sizeof (dr), &dr, 0, 0) < 0) {
		usb_debug ("set_address failed\n");
		usb_detach_device (controller, adr);
		return NULL;
	}
	mdelay (SET_ADDRESS_MDELAY);

	u8 buf[8];
	dev->address = adr;
	if (get_descriptor (dev, DR_DESC, DT_DEV, 0, buf, sizeof(buf))
			!= sizeof(buf)) {
		usb_debug("first get_descriptor(DT_DEV) failed\n");
		usb_detach_device (controller, adr);
		return NULL;
	}
	dev->endpoints[0].maxpacketsize = usb_decode_mps0(speed, buf[7]);

	return dev;
}

static int
set_address (hci_t *controller, usb_speed speed, int hubport, int hubaddr)
{
	usbdev_t *dev = controller->set_address(controller, speed,
						hubport, hubaddr);
	if (!dev) {
		usb_debug ("set_address failed\n");
		return -1;
	}

	dev->descriptor = malloc(sizeof(*dev->descriptor));
	if (!dev->descriptor || get_descriptor (dev, DR_DESC, DT_DEV, 0,
			dev->descriptor, sizeof(*dev->descriptor))
			!= sizeof(*dev->descriptor)) {
		usb_debug ("get_descriptor(DT_DEV) failed\n");
		usb_detach_device (controller, dev->address);
		return -1;
	}

	usb_debug ("* found device (0x%04x:0x%04x, USB %x.%x, MPS0: %d)\n",
		 dev->descriptor->idVendor, dev->descriptor->idProduct,
		 dev->descriptor->bcdUSB >> 8, dev->descriptor->bcdUSB & 0xff,
		 dev->endpoints[0].maxpacketsize);
	dev->quirks = usb_quirk_check(dev->descriptor->idVendor,
				      dev->descriptor->idProduct);

	usb_debug ("device has %d configurations\n",
		   dev->descriptor->bNumConfigurations);
	if (dev->descriptor->bNumConfigurations == 0) {
		/* device isn't usable */
		usb_debug ("... no usable configuration!\n");
		usb_detach_device (controller, dev->address);
		return -1;
	}

	u16 buf[2];
	if (get_descriptor (dev, DR_DESC, DT_CFG, 0, buf, sizeof(buf))
			!= sizeof(buf)) {
		usb_debug ("first get_descriptor(DT_CFG) failed\n");
		usb_detach_device (controller, dev->address);
		return -1;
	}
	/* workaround for some USB devices: wait until they're ready, or
	 * they send a NAK when they're not allowed to do. 1ms is enough */
	mdelay(1);
	dev->configuration = malloc(buf[1]);
	if (!dev->configuration) {
		usb_debug ("could not allocate %d bytes for DT_CFG\n", buf[1]);
		usb_detach_device (controller, dev->address);
		return -1;
	}
	if (get_descriptor (dev, DR_DESC, DT_CFG, 0, dev->configuration,
			    buf[1]) != buf[1]) {
		usb_debug ("get_descriptor(DT_CFG) failed\n");
		usb_detach_device (controller, dev->address);
		return -1;
	}
	configuration_descriptor_t *cd = dev->configuration;
	if (cd->wTotalLength != buf[1]) {
		usb_debug ("configuration descriptor size changed, aborting\n");
		usb_detach_device (controller, dev->address);
		return -1;
	}

	/*
	 * If the device is not well known (ifnum == -1), we use the first
	 * interface we encounter, as there was no need to implement something
	 * else for the time being. If you need it, see the SetInterface and
	 * GetInterface functions in the USB specification and set it yourself.
	 */
	usb_debug ("device has %x interfaces\n", cd->bNumInterfaces);
	int ifnum = usb_interface_check(dev->descriptor->idVendor,
					dev->descriptor->idProduct);
	if (cd->bNumInterfaces > 1 && ifnum < 0)
		usb_debug ("NOTICE: Your device has multiple interfaces and\n"
			   "this driver will only use the first one. That may\n"
			   "be the wrong choice and cause the device to not\n"
			   "work correctly. Please report this case\n"
			   "(including the above debugging output) to\n"
			   "coreboot@coreboot.org to have the device added to\n"
			   "the list of well-known quirks.\n");

	u8 *end = (void *)dev->configuration + cd->wTotalLength;
	interface_descriptor_t *intf;
	u8 *ptr;

	/* Find our interface (or the first good one if we don't know) */
	for (ptr = (void *)dev->configuration + sizeof(*cd); ; ptr += ptr[0]) {
		if (ptr + 2 > end || !ptr[0] || ptr + ptr[0] > end) {
			usb_debug ("Couldn't find usable DT_INTF\n");
			usb_detach_device (controller, dev->address);
			return -1;
		}
		if (ptr[1] != DT_INTF)
			continue;
		intf = (void *)ptr;
		if (intf->bLength != sizeof(*intf)) {
			usb_debug ("Skipping broken DT_INTF\n");
			continue;
		}
		if (ifnum >= 0 && intf->bInterfaceNumber != ifnum)
			continue;
		usb_debug ("Interface %d: class 0x%x, sub 0x%x. proto 0x%x\n",
			intf->bInterfaceNumber, intf->bInterfaceClass,
			intf->bInterfaceSubClass, intf->bInterfaceProtocol);
		ptr += sizeof(*intf);
		break;
	}

	/* Gather up all endpoints belonging to this interface */
	dev->num_endp = 1;
	for (; ptr + 2 <= end && ptr[0] && ptr + ptr[0] <= end; ptr += ptr[0]) {
		if (ptr[1] == DT_INTF || ptr[1] == DT_CFG ||
				dev->num_endp >= ARRAY_SIZE(dev->endpoints))
			break;
		if (ptr[1] != DT_ENDP)
			continue;

		endpoint_descriptor_t *desc = (void *)ptr;
		static const char *transfertypes[4] = {
			"control", "isochronous", "bulk", "interrupt"
		};
		usb_debug (" #Endpoint %d (%s), max packet size %x, type %s\n",
			desc->bEndpointAddress & 0x7f,
			(desc->bEndpointAddress & 0x80) ? "in" : "out",
			desc->wMaxPacketSize,
			transfertypes[desc->bmAttributes & 0x3]);

		endpoint_t *ep = &dev->endpoints[dev->num_endp++];
		ep->dev = dev;
		ep->endpoint = desc->bEndpointAddress;
		ep->toggle = 0;
		ep->maxpacketsize = desc->wMaxPacketSize;
		ep->direction = (desc->bEndpointAddress & 0x80) ? IN : OUT;
		ep->type = desc->bmAttributes & 0x3;
		ep->interval = usb_decode_interval (dev->speed, ep->type,
						    desc->bInterval);
	}

	if ((controller->finish_device_config &&
			controller->finish_device_config(dev)) ||
			set_configuration(dev) < 0) {
		usb_debug ("Could not finalize device configuration\n");
		usb_detach_device (controller, dev->address);
		return -1;
	}

	int class = dev->descriptor->bDeviceClass;
	if (class == 0)
		class = intf->bInterfaceClass;

	enum {
		audio_device      = 0x01,
		comm_device       = 0x02,
		hid_device        = 0x03,
		physical_device   = 0x05,
		imaging_device    = 0x06,
		printer_device    = 0x07,
		msc_device        = 0x08,
		hub_device        = 0x09,
		cdc_device        = 0x0a,
		ccid_device       = 0x0b,
		security_device   = 0x0d,
		video_device      = 0x0e,
		healthcare_device = 0x0f,
		diagnostic_device = 0xdc,
		wireless_device   = 0xe0,
		misc_device       = 0xef,
	};
	usb_debug("Class: ");
	switch (class) {
	case audio_device:
		usb_debug("audio\n");
		break;
	case comm_device:
		usb_debug("communication\n");
		break;
	case hid_device:
		usb_debug ("HID\n");
#if CONFIG(LP_USB_HID)
		dev->init = usb_hid_init;
		return dev->address;
#else
		usb_debug ("NOTICE: USB HID support not compiled in\n");
#endif
		break;
	case physical_device:
		usb_debug("physical\n");
		break;
	case imaging_device:
		usb_debug("camera\n");
		break;
	case printer_device:
		usb_debug("printer\n");
		break;
	case msc_device:
		usb_debug ("MSC\n");
#if CONFIG(LP_USB_MSC)
		dev->init = usb_msc_init;
		return dev->address;
#else
		usb_debug ("NOTICE: USB MSC support not compiled in\n");
#endif
		break;
	case hub_device:
		usb_debug ("hub\n");
#if CONFIG(LP_USB_HUB)
		dev->init = usb_hub_init;
		return dev->address;
#else
		usb_debug ("NOTICE: USB hub support not compiled in\n");
#endif
		break;
	case cdc_device:
		usb_debug("CDC\n");
		break;
	case ccid_device:
		usb_debug("smartcard / CCID\n");
		break;
	case security_device:
		usb_debug("content security\n");
		break;
	case video_device:
		usb_debug("video\n");
		break;
	case healthcare_device:
		usb_debug("healthcare\n");
		break;
	case diagnostic_device:
		usb_debug("diagnostic\n");
		break;
	case wireless_device:
		usb_debug("wireless\n");
		break;
	default:
		usb_debug("unsupported class %x\n", class);
		break;
	}
	dev->init = usb_generic_init;
	return dev->address;
}

/*
 * Should be called by the hub drivers whenever a physical detach occurs
 * and can be called by USB class drivers if they are unsatisfied with a
 * malfunctioning device.
 */
void
usb_detach_device(hci_t *controller, int devno)
{
	/* check if device exists, as we may have
	   been called yet by the USB class driver */
	if (controller->devices[devno]) {
		controller->devices[devno]->destroy (controller->devices[devno]);

		if (controller->destroy_device)
			controller->destroy_device(controller, devno);

		free(controller->devices[devno]->descriptor);
		controller->devices[devno]->descriptor = NULL;
		free(controller->devices[devno]->configuration);
		controller->devices[devno]->configuration = NULL;

		/* Tear down the device itself *after* destroy_device()
		 * has had a chance to interrogate it. */
		free(controller->devices[devno]);
		controller->devices[devno] = NULL;
	}
}

int
usb_attach_device(hci_t *controller, int hubaddress, int port, usb_speed speed)
{
	static const char *speeds[] = { "full", "low", "high", "super", "ultra" };
	usb_debug ("%sspeed device\n", (speed < sizeof(speeds) / sizeof(char*))
		? speeds[speed] : "invalid value - no");
	int newdev = set_address (controller, speed, port, hubaddress);
	if (newdev == -1)
		return -1;
	usbdev_t *newdev_t = controller->devices[newdev];
	// determine responsible driver - current done in set_address
	newdev_t->init (newdev_t);
	/* init() may have called usb_detach_device() yet, so check */
	return controller->devices[newdev] ? newdev : -1;
}

static void
usb_generic_destroy (usbdev_t *dev)
{
	if (usb_generic_remove)
		usb_generic_remove(dev);
}

void
usb_generic_init (usbdev_t *dev)
{
	dev->data = NULL;
	dev->destroy = usb_generic_destroy;

	if (usb_generic_create)
		usb_generic_create(dev);

	if (dev->data == NULL) {
		usb_debug("Detaching device not used by payload\n");
		usb_detach_device(dev->controller, dev->address);
	}
}

/*
 * returns the speed is above SUPER_SPEED or not
 */
_Bool is_usb_speed_ss(usb_speed speed)
{
	return (speed == SUPER_SPEED || speed == SUPER_SPEED_PLUS);
}

/*
 * returns the address of the closest USB2.0 hub, which is responsible for
 * split transactions, along with the number of the used downstream port
 */
int closest_usb2_hub(const usbdev_t *dev, int *const addr, int *const port)
{
	const usbdev_t *usb1dev;

	do {
		usb1dev = dev;
		if ((dev->hub >= 0) && (dev->hub < 128))
			dev = dev->controller->devices[dev->hub];
		else
			dev = NULL;
	} while (dev && (dev->speed < 2));

	if (dev) {
		*addr = usb1dev->hub;
		*port = usb1dev->port;
		return 0;
	}

	usb_debug("Couldn't find closest USB2.0 hub.\n");
	return 1;
}