path: root/drivers/usb/wusbcore/wusbhc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Wireless USB Host Controller
 * sysfs glue, wusbcore module support and life cycle management
 *
 *
 * Copyright (C) 2005-2006 Intel Corporation
 * Inaky Perez-Gonzalez <inaky.perez-gonzalez@intel.com>
 *
 * Creation/destruction of wusbhc is split in two parts; that that
 * doesn't require the HCD to be added (wusbhc_{create,destroy}) and
 * the one that requires (phase B, wusbhc_b_{create,destroy}).
 *
 * This is so because usb_add_hcd() will start the HC, and thus, all
 * the HC specific stuff has to be already initialized (like sysfs
 * thingies).
 */
#include <linux/device.h>
#include <linux/module.h>
#include "wusbhc.h"

/**
 * Extract the wusbhc that corresponds to a USB Host Controller class device
 *
 * WARNING! Apply only if @dev is that of a
 *          wusbhc.usb_hcd.self->class_dev; otherwise, you loose.
 */
static struct wusbhc *usbhc_dev_to_wusbhc(struct device *dev)
{
	struct usb_bus *usb_bus = dev_get_drvdata(dev);
	struct usb_hcd *usb_hcd = bus_to_hcd(usb_bus);
	return usb_hcd_to_wusbhc(usb_hcd);
}

/*
 * Show & store the current WUSB trust timeout
 *
 * We don't do locking--it is an 'atomic' value.
 *
 * The units that we store/show are always MILLISECONDS. However, the
 * value of trust_timeout is jiffies.
 */
static ssize_t wusb_trust_timeout_show(struct device *dev,
					struct device_attribute *attr,
					char *buf)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);

	return scnprintf(buf, PAGE_SIZE, "%u\n", wusbhc->trust_timeout);
}

static ssize_t wusb_trust_timeout_store(struct device *dev,
					struct device_attribute *attr,
					const char *buf, size_t size)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
	ssize_t result = -ENOSYS;
	unsigned trust_timeout;

	result = sscanf(buf, "%u", &trust_timeout);
	if (result != 1) {
		result = -EINVAL;
		goto out;
	}
	wusbhc->trust_timeout = min_t(unsigned, trust_timeout, 500);
	cancel_delayed_work(&wusbhc->keep_alive_timer);
	flush_workqueue(wusbd);
	queue_delayed_work(wusbd, &wusbhc->keep_alive_timer,
			   msecs_to_jiffies(wusbhc->trust_timeout / 2));
out:
	return result < 0 ? result : size;
}
static DEVICE_ATTR_RW(wusb_trust_timeout);

/*
 * Show the current WUSB CHID.
 */
static ssize_t wusb_chid_show(struct device *dev,
			      struct device_attribute *attr, char *buf)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
	const struct wusb_ckhdid *chid;
	ssize_t result = 0;

	if (wusbhc->wuie_host_info != NULL)
		chid = &wusbhc->wuie_host_info->CHID;
	else
		chid = &wusb_ckhdid_zero;

	result += ckhdid_printf(buf, PAGE_SIZE, chid);
	result += sprintf(buf + result, "\n");

	return result;
}

/*
 * Store a new CHID.
 *
 * - Write an all zeros CHID and it will stop the controller
 * - Write a non-zero CHID and it will start it.
 *
 * See wusbhc_chid_set() for more info.
 */
static ssize_t wusb_chid_store(struct device *dev,
			       struct device_attribute *attr,
			       const char *buf, size_t size)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
	struct wusb_ckhdid chid;
	ssize_t result;

	result = sscanf(buf,
			"%02hhx %02hhx %02hhx %02hhx "
			"%02hhx %02hhx %02hhx %02hhx "
			"%02hhx %02hhx %02hhx %02hhx "
			"%02hhx %02hhx %02hhx %02hhx\n",
			&chid.data[0] , &chid.data[1] ,
			&chid.data[2] , &chid.data[3] ,
			&chid.data[4] , &chid.data[5] ,
			&chid.data[6] , &chid.data[7] ,
			&chid.data[8] , &chid.data[9] ,
			&chid.data[10], &chid.data[11],
			&chid.data[12], &chid.data[13],
			&chid.data[14], &chid.data[15]);
	if (result != 16) {
		dev_err(dev, "Unrecognized CHID (need 16 8-bit hex digits): "
			"%d\n", (int)result);
		return -EINVAL;
	}
	result = wusbhc_chid_set(wusbhc, &chid);
	return result < 0 ? result : size;
}
static DEVICE_ATTR_RW(wusb_chid);


static ssize_t wusb_phy_rate_show(struct device *dev,
				  struct device_attribute *attr,
				  char *buf)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);

	return sprintf(buf, "%d\n", wusbhc->phy_rate);
}

static ssize_t wusb_phy_rate_store(struct device *dev,
				   struct device_attribute *attr,
				   const char *buf, size_t size)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
	uint8_t phy_rate;
	ssize_t result;

	result = sscanf(buf, "%hhu", &phy_rate);
	if (result != 1)
		return -EINVAL;
	if (phy_rate >= UWB_PHY_RATE_INVALID)
		return -EINVAL;

	wusbhc->phy_rate = phy_rate;
	return size;
}
static DEVICE_ATTR_RW(wusb_phy_rate);

static ssize_t wusb_dnts_show(struct device *dev,
				  struct device_attribute *attr,
				  char *buf)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);

	return sprintf(buf, "num slots: %d\ninterval: %dms\n",
			wusbhc->dnts_num_slots, wusbhc->dnts_interval);
}

static ssize_t wusb_dnts_store(struct device *dev,
				   struct device_attribute *attr,
				   const char *buf, size_t size)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
	uint8_t num_slots, interval;
	ssize_t result;

	result = sscanf(buf, "%hhu %hhu", &num_slots, &interval);

	if (result != 2)
		return -EINVAL;

	wusbhc->dnts_num_slots = num_slots;
	wusbhc->dnts_interval = interval;

	return size;
}
static DEVICE_ATTR_RW(wusb_dnts);

static ssize_t wusb_retry_count_show(struct device *dev,
				  struct device_attribute *attr,
				  char *buf)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);

	return sprintf(buf, "%d\n", wusbhc->retry_count);
}

static ssize_t wusb_retry_count_store(struct device *dev,
				   struct device_attribute *attr,
				   const char *buf, size_t size)
{
	struct wusbhc *wusbhc = usbhc_dev_to_wusbhc(dev);
	uint8_t retry_count;
	ssize_t result;

	result = sscanf(buf, "%hhu", &retry_count);

	if (result != 1)
		return -EINVAL;

	wusbhc->retry_count = max_t(uint8_t, retry_count,
					WUSB_RETRY_COUNT_MAX);

	return size;
}
static DEVICE_ATTR_RW(wusb_retry_count);

/* Group all the WUSBHC attributes */
static struct attribute *wusbhc_attrs[] = {
		&dev_attr_wusb_trust_timeout.attr,
		&dev_attr_wusb_chid.attr,
		&dev_attr_wusb_phy_rate.attr,
		&dev_attr_wusb_dnts.attr,
		&dev_attr_wusb_retry_count.attr,
		NULL,
};

static const struct attribute_group wusbhc_attr_group = {
	.name = NULL,	/* we want them in the same directory */
	.attrs = wusbhc_attrs,
};

/*
 * Create a wusbhc instance
 *
 * NOTEs:
 *
 *  - assumes *wusbhc has been zeroed and wusbhc->usb_hcd has been
 *    initialized but not added.
 *
 *  - fill out ports_max, mmcies_max and mm