src/libpayload/drivers/usb/generic_hub.c - third_party/depthcharge - Git at Google

 /*
  * Copyright (C) 2013 secunet Security Networks AG
  *
  * 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 <stdlib.h>
 #include <usb/usb.h>
 #include "generic_hub.h"

 #include "base/time.h"

 enum {
 	GenericHub_NoDev = -1,
 };

 void generic_hub_destroy(UsbDev *const dev)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);
 	if (!hub)
 		return;

 	// First, detach all devices behind this hub.
 	for (int port = 1; port <= hub->num_ports; port++) {
 		if (hub->ports[port] >= 0) {
 			usb_debug("generic_hub: Detachment at port %d\n", port);
 			usb_detach_device(dev->controller, hub->ports[port]);
 			hub->ports[port] = GenericHub_NoDev;
 		}
 	}

 	// Disable all ports.
 	if (hub->ops->disable_port)
 		for (int port = 1; port <= hub->num_ports; port++)
 			hub->ops->disable_port(dev, port);

 	free(hub->ports);
 	free(hub);
 }

 static int generic_hub_debounce(UsbDev *const dev, const int port)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);

 	const int step_ms = 1; // linux uses 25ms, we're busy anyway.
 	const int at_least_ms = 100; // 100ms as in usb20 spec 9.1.2.
 	const int timeout_ms = 1500; // linux uses this value.

 	int total_ms = 0;
 	int stable_ms = 0;
 	while (stable_ms < at_least_ms && total_ms < timeout_ms) {
 		mdelay(step_ms);

 		const int changed = hub->ops->port_status_changed(dev, port);
 		const int connected = hub->ops->port_connected(dev, port);
 		if (changed < 0 || connected < 0)
 			return -1;

 		if (!changed && connected) {
 			stable_ms += step_ms;
 		} else {
 			usb_debug("generic_hub: Unstable connection at %d\n",
 				  port);
 			stable_ms = 0;
 		}
 		total_ms += step_ms;
 	}
 	if (total_ms >= timeout_ms)
 		usb_debug("generic_hub: Debouncing timed out at %d\n", port);
 	return 0; // Ignore timeouts, try to always go on.
 }

 int generic_hub_wait_for_port(UsbDev *const dev, const int port,
 			      const int wait_for,
 			      int (*const port_op)(UsbDev *, int),
 			      int timeout_steps, const int step_us)
 {
 	do {
 		int state = port_op(dev, port);
 		if (state < 0)
 			return -1;
 		else if (!!state == wait_for)
 			return timeout_steps;
 		udelay(step_us);
 		timeout_steps--;
 	} while(timeout_steps);

 	return 0;
 }

 int generic_hub_resetport(UsbDev *const dev, const int port)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);

 	if (hub->ops->start_port_reset(dev, port) < 0)
 		return -1;

 	// Wait for 10ms. (usb20 spec 11.5.1.5: reset should take 10 to 20ms)
 	mdelay(10);

 	// Now wait 12ms for the hub to finish the reset.
 	const int ret = generic_hub_wait_for_port(
 			// Time out after 120 * 100us = 12ms.
 			dev, port, 0, hub->ops->port_in_reset, 120, 100);
 	if (ret < 0)
 		return -1;
 	else if (!ret)
 		usb_debug("generic_hub: Reset timed out at port %d\n", port);

 	return 0; // Ignore timeouts, try to always go on.
 }

 static int generic_hub_detach_dev(UsbDev *const dev, const int port)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);

 	usb_detach_device(dev->controller, hub->ports[port]);
 	hub->ports[port] = GenericHub_NoDev;

 	return 0;
 }

 static int generic_hub_attach_dev(UsbDev *const dev, const int port)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);

 	if (generic_hub_debounce(dev, port) < 0)
 		return -1;

 	if (hub->ops->reset_port) {
 		if (hub->ops->reset_port(dev, port) < 0)
 			return -1;
 		// After reset the port will be enabled automatically.
 		const int ret = generic_hub_wait_for_port(
 			// Time out after 1,000 * 10us = 10ms.
 			dev, port, 1, hub->ops->port_enabled, 1000, 10);
 		if (ret < 0)
 			return -1;
 		else if (!ret)
 			usb_debug("generic_hub: Port %d still "
 				  "disabled after 10ms\n", port);
 	}

 	const UsbSpeed speed = hub->ops->port_speed(dev, port);
 	if (speed >= 0) {
 		usb_debug("generic_hub: Success at port %d\n", port);
 		if (hub->ops->reset_port)
 			mdelay(10); // Reset recovery time. (usb20 spec 7.1.7.5)
 		hub->ports[port] = usb_attach_device(
 				dev->controller, dev->address, port, speed);
 	}
 	return 0;
 }

 int generic_hub_scanport(UsbDev *const dev, const int port)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);

 	if (hub->ports[port] >= 0) {
 		usb_debug("generic_hub: Detachment at port %d\n", port);

 		const int ret = generic_hub_detach_dev(dev, port);
 		if (ret < 0)
 			return ret;
 	}

 	if (hub->ops->port_connected(dev, port)) {
 		usb_debug("generic_hub: Attachment at port %d\n", port);

 		return generic_hub_attach_dev(dev, port);
 	}

 	return 0;
 }

 static void generic_hub_poll(UsbDev *const dev)
 {
 	generic_hub_t *const hub = GEN_HUB(dev);
 	if (!hub)
 		return;

 	if (hub->ops->hub_status_changed &&
 			hub->ops->hub_status_changed(dev) != 1)
 		return;

 	for (int port = 1; port <= hub->num_ports; port++) {
 		const int ret = hub->ops->port_status_changed(dev, port);
 		if (ret < 0) {
 			return;
 		} else if (ret == 1) {
 			usb_debug("generic_hub: Port change at %d\n", port);
 			if (generic_hub_scanport(dev, port) < 0)
 				return;
 		}
 	}
 }

 int generic_hub_init(UsbDev *const dev, const int num_ports,
 		     const GenericHubOps *const ops)
 {
 	dev->destroy = generic_hub_destroy;
 	dev->poll = generic_hub_poll;
 	dev->data = malloc(sizeof(generic_hub_t));
 	if (!dev->data) {
 		usb_debug("generic_hub: ERROR: Out of memory\n");
 		return -1;
 	}

 	generic_hub_t *const hub = GEN_HUB(dev);
 	hub->num_ports = num_ports;
 	hub->ports = malloc(sizeof(*hub->ports) * (num_ports + 1));
 	hub->ops = ops;
 	if (!hub->ports) {
 		usb_debug("generic_hub: ERROR: Out of memory\n");
 		free(dev->data);
 		dev->data = NULL;
 		return -1;
 	}
 	for (int port = 1; port <= num_ports; ++port)
 		hub->ports[port] = GenericHub_NoDev;

 	// Enable all ports.
 	if (ops->enable_port) {
 		for (int port = 1; port <= num_ports; ++port)
 			ops->enable_port(dev, port);
 		// Wait once for all ports.
 		mdelay(20);
 	}

 	return 0;
 }
	/*
	* Copyright (C) 2013 secunet Security Networks AG
	*
	* 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 <stdlib.h>
	#include <usb/usb.h>
	#include "generic_hub.h"

	#include "base/time.h"

	enum {
	GenericHub_NoDev = -1,
	};

	void generic_hub_destroy(UsbDev *const dev)
	{
	generic_hub_t *const hub = GEN_HUB(dev);
	if (!hub)
	return;

	// First, detach all devices behind this hub.
	for (int port = 1; port <= hub->num_ports; port++) {
	if (hub->ports[port] >= 0) {
	usb_debug("generic_hub: Detachment at port %d\n", port);
	usb_detach_device(dev->controller, hub->ports[port]);
	hub->ports[port] = GenericHub_NoDev;
	}
	}

	// Disable all ports.
	if (hub->ops->disable_port)
	for (int port = 1; port <= hub->num_ports; port++)
	hub->ops->disable_port(dev, port);

	free(hub->ports);
	free(hub);
	}

	static int generic_hub_debounce(UsbDev *const dev, const int port)
	{
	generic_hub_t *const hub = GEN_HUB(dev);

	const int step_ms = 1; // linux uses 25ms, we're busy anyway.
	const int at_least_ms = 100; // 100ms as in usb20 spec 9.1.2.
	const int timeout_ms = 1500; // linux uses this value.

	int total_ms = 0;
	int stable_ms = 0;
	while (stable_ms < at_least_ms && total_ms < timeout_ms) {
	mdelay(step_ms);

	const int changed = hub->ops->port_status_changed(dev, port);
	const int connected = hub->ops->port_connected(dev, port);
	if (changed < 0 \|\| connected < 0)
	return -1;

	if (!changed && connected) {
	stable_ms += step_ms;
	} else {
	usb_debug("generic_hub: Unstable connection at %d\n",
	port);
	stable_ms = 0;
	}
	total_ms += step_ms;
	}
	if (total_ms >= timeout_ms)
	usb_debug("generic_hub: Debouncing timed out at %d\n", port);
	return 0; // Ignore timeouts, try to always go on.
	}

	int generic_hub_wait_for_port(UsbDev *const dev, const int port,
	const int wait_for,
	int (const port_op)(UsbDev , int),
	int timeout_steps, const int step_us)
	{
	do {
	int state = port_op(dev, port);
	if (state < 0)
	return -1;
	else if (!!state == wait_for)
	return timeout_steps;
	udelay(step_us);
	timeout_steps--;
	} while(timeout_steps);

	return 0;
	}

	int generic_hub_resetport(UsbDev *const dev, const int port)
	{
	generic_hub_t *const hub = GEN_HUB(dev);

	if (hub->ops->start_port_reset(dev, port) < 0)
	return -1;

	// Wait for 10ms. (usb20 spec 11.5.1.5: reset should take 10 to 20ms)
	mdelay(10);

	// Now wait 12ms for the hub to finish the reset.
	const int ret = generic_hub_wait_for_port(
	// Time out after 120 * 100us = 12ms.
	dev, port, 0, hub->ops->port_in_reset, 120, 100);
	if (ret < 0)
	return -1;
	else if (!ret)
	usb_debug("generic_hub: Reset timed out at port %d\n", port);

	return 0; // Ignore timeouts, try to always go on.
	}

	static int generic_hub_detach_dev(UsbDev *const dev, const int port)
	{
	generic_hub_t *const hub = GEN_HUB(dev);

	usb_detach_device(dev->controller, hub->ports[port]);
	hub->ports[port] = GenericHub_NoDev;

	return 0;
	}

	static int generic_hub_attach_dev(UsbDev *const dev, const int port)
	{
	generic_hub_t *const hub = GEN_HUB(dev);

	if (generic_hub_debounce(dev, port) < 0)
	return -1;

	if (hub->ops->reset_port) {
	if (hub->ops->reset_port(dev, port) < 0)
	return -1;
	// After reset the port will be enabled automatically.
	const int ret = generic_hub_wait_for_port(
	// Time out after 1,000 * 10us = 10ms.
	dev, port, 1, hub->ops->port_enabled, 1000, 10);
	if (ret < 0)
	return -1;
	else if (!ret)
	usb_debug("generic_hub: Port %d still "
	"disabled after 10ms\n", port);
	}

	const UsbSpeed speed = hub->ops->port_speed(dev, port);
	if (speed >= 0) {
	usb_debug("generic_hub: Success at port %d\n", port);
	if (hub->ops->reset_port)
	mdelay(10); // Reset recovery time. (usb20 spec 7.1.7.5)
	hub->ports[port] = usb_attach_device(
	dev->controller, dev->address, port, speed);
	}
	return 0;
	}

	int generic_hub_scanport(UsbDev *const dev, const int port)
	{
	generic_hub_t *const hub = GEN_HUB(dev);

	if (hub->ports[port] >= 0) {
	usb_debug("generic_hub: Detachment at port %d\n", port);

	const int ret = generic_hub_detach_dev(dev, port);
	if (ret < 0)
	return ret;
	}

	if (hub->ops->port_connected(dev, port)) {
	usb_debug("generic_hub: Attachment at port %d\n", port);

	return generic_hub_attach_dev(dev, port);
	}

	return 0;
	}

	static void generic_hub_poll(UsbDev *const dev)
	{
	generic_hub_t *const hub = GEN_HUB(dev);
	if (!hub)
	return;

	if (hub->ops->hub_status_changed &&
	hub->ops->hub_status_changed(dev) != 1)
	return;

	for (int port = 1; port <= hub->num_ports; port++) {
	const int ret = hub->ops->port_status_changed(dev, port);
	if (ret < 0) {
	return;
	} else if (ret == 1) {
	usb_debug("generic_hub: Port change at %d\n", port);
	if (generic_hub_scanport(dev, port) < 0)
	return;
	}
	}
	}

	int generic_hub_init(UsbDev *const dev, const int num_ports,
	const GenericHubOps *const ops)
	{
	dev->destroy = generic_hub_destroy;
	dev->poll = generic_hub_poll;
	dev->data = malloc(sizeof(generic_hub_t));
	if (!dev->data) {
	usb_debug("generic_hub: ERROR: Out of memory\n");
	return -1;
	}

	generic_hub_t *const hub = GEN_HUB(dev);
	hub->num_ports = num_ports;
	hub->ports = malloc(sizeof(hub->ports) (num_ports + 1));
	hub->ops = ops;
	if (!hub->ports) {
	usb_debug("generic_hub: ERROR: Out of memory\n");
	free(dev->data);
	dev->data = NULL;
	return -1;
	}
	for (int port = 1; port <= num_ports; ++port)
	hub->ports[port] = GenericHub_NoDev;

	// Enable all ports.
	if (ops->enable_port) {
	for (int port = 1; port <= num_ports; ++port)
	ops->enable_port(dev, port);
	// Wait once for all ports.
	mdelay(20);
	}

	return 0;
	}