[linux-2.6-block.git] / drivers / thunderbolt / retimer.c

// SPDX-License-Identifier: GPL-2.0
/*
 * Thunderbolt/USB4 retimer support.
 *
 * Copyright (C) 2020, Intel Corporation
 * Authors: Kranthi Kuntala <kranthi.kuntala@intel.com>
 *	    Mika Westerberg <mika.westerberg@linux.intel.com>
 */

#include <linux/delay.h>
#include <linux/pm_runtime.h>
#include <linux/sched/signal.h>

#include "sb_regs.h"
#include "tb.h"

#define TB_MAX_RETIMER_INDEX	6

/**
 * tb_retimer_nvm_read() - Read contents of retimer NVM
 * @rt: Retimer device
 * @address: NVM address (in bytes) to start reading
 * @buf: Data read from NVM is stored here
 * @size: Number of bytes to read
 *
 * Reads retimer NVM and copies the contents to @buf. Returns %0 if the
 * read was successful and negative errno in case of failure.
 */
int tb_retimer_nvm_read(struct tb_retimer *rt, unsigned int address, void *buf,
			size_t size)
{
	return usb4_port_retimer_nvm_read(rt->port, rt->index, address, buf, size);
}

static int nvm_read(void *priv, unsigned int offset, void *val, size_t bytes)
{
	struct tb_nvm *nvm = priv;
	struct tb_retimer *rt = tb_to_retimer(nvm->dev);
	int ret;

	pm_runtime_get_sync(&rt->dev);

	if (!mutex_trylock(&rt->tb->lock)) {
		ret = restart_syscall();
		goto out;
	}

	ret = tb_retimer_nvm_read(rt, offset, val, bytes);
	mutex_unlock(&rt->tb->lock);

out:
	pm_runtime_mark_last_busy(&rt->dev);
	pm_runtime_put_autosuspend(&rt->dev);

	return ret;
}

static int nvm_write(void *priv, unsigned int offset, void *val, size_t bytes)
{
	struct tb_nvm *nvm = priv;
	struct tb_retimer *rt = tb_to_retimer(nvm->dev);
	int ret = 0;

	if (!mutex_trylock(&rt->tb->lock))
		return restart_syscall();

	ret = tb_nvm_write_buf(nvm, offset, val, bytes);
	mutex_unlock(&rt->tb->lock);

	return ret;
}

static int tb_retimer_nvm_add(struct tb_retimer *rt)
{
	struct tb_nvm *nvm;
	int ret;

	nvm = tb_nvm_alloc(&rt->dev);
	if (IS_ERR(nvm)) {
		ret = PTR_ERR(nvm) == -EOPNOTSUPP ? 0 : PTR_ERR(nvm);
		goto err_nvm;
	}

	ret = tb_nvm_read_version(nvm);
	if (ret)
		goto err_nvm;

	ret = tb_nvm_add_active(nvm, nvm_read);
	if (ret)
		goto err_nvm;

	ret = tb_nvm_add_non_active(nvm, nvm_write);
	if (ret)
		goto err_nvm;

	rt->nvm = nvm;
	return 0;

err_nvm:
	dev_dbg(&rt->dev, "NVM upgrade disabled\n");
	if (!IS_ERR(nvm))
		tb_nvm_free(nvm);

	return ret;
}

static int tb_retimer_nvm_validate_and_write(struct tb_retimer *rt)
{
	unsigned int image_size;
	const u8 *buf;
	int ret;

	ret = tb_nvm_validate(rt->nvm);
	if (ret)
		return ret;

	buf = rt->nvm->buf_data_start;
	image_size = rt->nvm->buf_data_size;

	ret = usb4_port_retimer_nvm_write(rt->port, rt->index, 0, buf,
					 image_size);
	if (ret)
		return ret;

	rt->nvm->flushed = true;
	return 0;
}

static int tb_retimer_nvm_authenticate(struct tb_retimer *rt, bool auth_only)
{
	u32 status;
	int ret;

	if (auth_only) {
		ret = usb4_port_retimer_nvm_set_offset(rt->port, rt->index, 0);
		if (ret)
			return ret;
	}

	ret = usb4_port_retimer_nvm_authenticate(rt->port, rt->index);
	if (ret)
		return ret;

	usleep_range(100, 150);

	/*
	 * Check the status now if we still can access the retimer. It
	 * is expected that the below fails.
	 */
	ret = usb4_port_retimer_nvm_authenticate_status(rt->port, rt->index,
							&status);
	if (!ret) {
		rt->auth_status = status;
		return status ? -EINVAL : 0;
	}

	return 0;
}

static ssize_t device_show(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	struct tb_retimer *rt = tb_to_retimer(dev);

	return sysfs_emit(buf, "%#x\n", rt->device);
}
static DEVICE_ATTR_RO(device);

static ssize_t nvm_authenticate_show(struct device *dev,
	struct device_attribute *attr, char *buf)
{
	struct tb_retimer *rt = tb_to_retimer(dev);
	int ret;

	if (!mutex_trylock(&rt->tb->lock))
		return restart_syscall();

	if (!rt->nvm)
		ret = -EAGAIN;
	else if (rt->no_nvm_upgrade)
		ret = -EOPNOTSUPP;
	else
		ret = sysfs_emit(buf, "%#x\n", rt->auth_status);

	mutex_unlock(&rt->tb->lock);

	return ret;
}

static void tb_retimer_set_inbound_sbtx(struct tb_port *port)
{
	int i;

	for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
		usb4_port_retimer_set_inbound_sbtx(port, i);
}

static void tb_retimer_unset_inbound_sbtx(struct tb_port *port)
{
	int i;

	for (i = TB_MAX_RETIMER_INDEX; i >= 1; i--)
		usb4_port_retimer_unset_inbound_sbtx(port, i);
}

static ssize_t nvm_authenticate_store(struct device *dev,
	struct device_attribute *attr, const char *buf, size_t count)
{
	struct tb_retimer *rt = tb_to_retimer(dev);
	int val, ret;

	pm_runtime_get_sync(&rt->dev);

	if (!mutex_trylock(&rt->tb->lock)) {
		ret = restart_syscall();
		goto exit_rpm;
	}

	if (!rt->nvm) {
		ret = -EAGAIN;
		goto exit_unlock;
	}

	ret = kstrtoint(buf, 10, &val);
	if (ret)
		goto exit_unlock;

	/* Always clear status */
	rt->auth_status = 0;

	if (val) {
		tb_retimer_set_inbound_sbtx(rt->port);
		if (val == AUTHENTICATE_ONLY) {
			ret = tb_retimer_nvm_authenticate(rt, true);
		} else {
			if (!rt->nvm->flushed) {
				if (!rt->nvm->buf) {
					ret = -EINVAL;
					goto exit_unlock;
				}

				ret = tb_retimer_nvm_validate_and_write(rt);
				if (ret || val == WRITE_ONLY)
					goto exit_unlock;
			}
			if (val == WRITE_AND_AUTHENTICATE)
				ret = tb_retimer_nvm_authenticate(rt, false);
		}
	}

exit_unlock:
	tb_retimer_unset_inbound_sbtx(rt->port);
	mutex_unlock(&rt->tb->lock);
exit_rpm:
	pm_runtime_mark_last_busy(&rt->dev);
	pm_runtime_put_autosuspend(&rt->dev);

	if (ret)
		return ret;
	return count;
}
static DEVICE_ATTR_RW(nvm_authenticate);

static ssize_t nvm_version_show(struct device *dev,
				struct device_attribute *attr, char *buf)
{
	struct tb_retimer *rt = tb_to_retimer(dev);
	int ret;

	if (!mutex_trylock(&rt->tb->lock))
		return restart_syscall();

	if (!rt->nvm)
		ret = -EAGAIN;
	else
		ret = sysfs_emit(buf, "%x.%x\n", rt->nvm->major, rt->nvm->minor);

	mutex_unlock(&rt->tb->lock);
	return ret;
}
static DEVICE_ATTR_RO(nvm_version);

static ssize_t vendor_show(struct device *dev, struct device_attribute *attr,
			   char *buf)
{
	struct tb_retimer *rt = tb_to_retimer(dev);

	return sysfs_emit(buf, "%#x\n", rt->vendor);
}
static DEVICE_ATTR_RO(vendor);

static struct attribute *retimer_attrs[] = {
	&dev_attr_device.attr,
	&dev_attr_nvm_authenticate.attr,
	&dev_attr_nvm_version.attr,
	&dev_attr_vendor.attr,
	NULL
};

static const struct attribute_group retimer_group = {
	.attrs = retimer_attrs,
};

static const struct attribute_group *retimer_groups[] = {
	&retimer_group,
	NULL
};

static void tb_retimer_release(struct device *dev)
{
	struct tb_retimer *rt = tb_to_retimer(dev);

	kfree(rt);
}

struct device_type tb_retimer_type = {
	.name = "thunderbolt_retimer",
	.groups = retimer_groups,
	.release = tb_retimer_release,
};

static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
{
	struct tb_retimer *rt;
	u32 vendor, device;
	int ret;

	ret = usb4_port_retimer_read(port, index, USB4_SB_VENDOR_ID, &vendor,
				     sizeof(vendor));
	if (ret) {
		if (ret != -ENODEV)
			tb_port_warn(port, "failed read retimer VendorId: %d\n", ret);
		return ret;
	}

	ret = usb4_port_retimer_read(port, index, USB4_SB_PRODUCT_ID, &device,
				     sizeof(device));
	if (ret) {
		if (ret != -ENODEV)
			tb_port_warn(port, "failed read retimer ProductId: %d\n", ret);
		return ret;
	}

	if (vendor != PCI_VENDOR_ID_INTEL && vendor != 0x8087) {
		tb_port_info(port, "retimer NVM format of vendor %#x is not supported\n",
			     vendor);
		return -EOPNOTSUPP;
	}

	/*
	 * Check that it supports NVM operations. If not then don't add
	 * the device at all.
	 */
	ret = usb4_port_retimer_nvm_sector_size(port, index);
	if (ret < 0)
		return ret;

	rt = kzalloc(sizeof(*rt), GFP_KERNEL);
	if (!rt)
		return -ENOMEM;

	rt->index = index;
	rt->vendor = vendor;
	rt->device = device;
	rt->auth_status = auth_status;
	rt->port = port;
	rt->tb = port->sw->tb;

	rt->dev.parent = &port->usb4->dev;
	rt->dev.bus = &tb_bus_type;
	rt->dev.type = &tb_retimer_type;
	dev_set_name(&rt->dev, "%s:%u.%u", dev_name(&port->sw->dev),
		     port->port, index);

	ret = device_register(&rt->dev);
	if (ret) {
		dev_err(&rt->dev, "failed to register retimer: %d\n", ret);
		put_device(&rt->dev);
		return ret;
	}

	ret = tb_retimer_nvm_add(rt);
	if (ret) {
		dev_err(&rt->dev, "failed to add NVM devices: %d\n", ret);
		device_unregister(&rt->dev);
		return ret;
	}

	dev_info(&rt->dev, "new retimer found, vendor=%#x device=%#x\n",
		 rt->vendor, rt->device);

	pm_runtime_no_callbacks(&rt->dev);
	pm_runtime_set_active(&rt->dev);
	pm_runtime_enable(&rt->dev);
	pm_runtime_set_autosuspend_delay(&rt->dev, TB_AUTOSUSPEND_DELAY);
	pm_runtime_mark_last_busy(&rt->dev);
	pm_runtime_use_autosuspend(&rt->dev);

	return 0;
}

static void tb_retimer_remove(struct tb_retimer *rt)
{
	dev_info(&rt->dev, "retimer disconnected\n");
	tb_nvm_free(rt->nvm);
	device_unregister(&rt->dev);
}

struct tb_retimer_lookup {
	const struct tb_port *port;
	u8 index;
};

static int retimer_match(struct device *dev, void *data)
{
	const struct tb_retimer_lookup *lookup = data;
	struct tb_retimer *rt = tb_to_retimer(dev);

	return rt && rt->port == lookup->port && rt->index == lookup->index;
}

static struct tb_retimer *tb_port_find_retimer(struct tb_port *port, u8 index)
{
	struct tb_retimer_lookup lookup = { .port = port, .index = index };
	struct device *dev;

	dev = device_find_child(&port->usb4->dev, &lookup, retimer_match);
	if (dev)
		return tb_to_retimer(dev);

	return NULL;
}

/**
 * tb_retimer_scan() - Scan for on-board retimers under port
 * @port: USB4 port to scan
 * @add: If true also registers found retimers
 *
 * Brings the sideband into a state where retimers can be accessed.
 * Then Tries to enumerate on-board retimers connected to @port. Found
 * retimers are registered as children of @port if @add is set.  Does
 * not scan for cable retimers for now.
 */
int tb_retimer_scan(struct tb_port *port, bool add)
{
	u32 status[TB_MAX_RETIMER_INDEX + 1] = {};
	int ret, i, last_idx = 0;

	/*
	 * Send broadcast RT to make sure retimer indices facing this
	 * port are set.
	 */
	ret = usb4_port_enumerate_retimers(port);
	if (ret)
		return ret;

	/*
	 * Enable sideband channel for each retimer. We can do this
	 * regardless whether there is device connected or not.
	 */
	tb_retimer_set_inbound_sbtx(port);

	/*
	 * Before doing anything else, read the authentication status.
	 * If the retimer has it set, store it for the new retimer
	 * device instance.
	 */
	for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
		usb4_port_retimer_nvm_authenticate_status(port, i, &status[i]);

	for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) {
		/*
		 * Last retimer is true only for the last on-board
		 * retimer (the one connected directly to the Type-C
		 * port).
		 */
		ret = usb4_port_retimer_is_last(port, i);
		if (ret > 0)
			last_idx = i;
		else if (ret < 0)
			break;
	}

	tb_retimer_unset_inbound_sbtx(port);

	if (!last_idx)
		return 0;

	/* Add on-board retimers if they do not exist already */
	ret = 0;
	for (i = 1; i <= last_idx; i++) {
		struct tb_retimer *rt;

		rt = tb_port_find_retimer(port, i);
		if (rt) {
			put_device(&rt->dev);
		} else if (add) {
			ret = tb_retimer_add(port, i, status[i]);
			if (ret && ret != -EOPNOTSUPP)
				break;
		}
	}

	return ret;
}

static int remove_retimer(struct device *dev, void *data)
{
	struct tb_retimer *rt = tb_to_retimer(dev);
	struct tb_port *port = data;

	if (rt && rt->port == port)
		tb_retimer_remove(rt);
	return 0;
}

/**
 * tb_retimer_remove_all() - Remove all retimers under port
 * @port: USB4 port whose retimers to remove
 *
 * This removes all previously added retimers under @port.
 */
void tb_retimer_remove_all(struct tb_port *port)
{
	struct usb4_port *usb4;

	usb4 = port->usb4;
	if (usb4)
		device_for_each_child_reverse(&usb4->dev, port,
					      remove_retimer);
}
Commit	Line	Data
dacb1287 KK	1	// SPDX-License-Identifier: GPL-2.0
	2	/*
	3	* Thunderbolt/USB4 retimer support.
	4	*
	5	* Copyright (C) 2020, Intel Corporation
	6	* Authors: Kranthi Kuntala <kranthi.kuntala@intel.com>
	7	* Mika Westerberg <mika.westerberg@linux.intel.com>
	8	*/
	9
	10	#include <linux/delay.h>
	11	#include <linux/pm_runtime.h>
	12	#include <linux/sched/signal.h>
	13
	14	#include "sb_regs.h"
	15	#include "tb.h"
	16
	17	#define TB_MAX_RETIMER_INDEX 6
	18
8b02b2da MW	19	/**
	20	* tb_retimer_nvm_read() - Read contents of retimer NVM
	21	* @rt: Retimer device
	22	* @address: NVM address (in bytes) to start reading
	23	* @buf: Data read from NVM is stored here
	24	* @size: Number of bytes to read
	25	*
	26	* Reads retimer NVM and copies the contents to @buf. Returns %0 if the
	27	* read was successful and negative errno in case of failure.
	28	*/
	29	int tb_retimer_nvm_read(struct tb_retimer rt, unsigned int address, void buf,
	30	size_t size)
	31	{
	32	return usb4_port_retimer_nvm_read(rt->port, rt->index, address, buf, size);
	33	}
	34
	35	static int nvm_read(void priv, unsigned int offset, void val, size_t bytes)
dacb1287 KK	36	{
	37	struct tb_nvm *nvm = priv;
	38	struct tb_retimer *rt = tb_to_retimer(nvm->dev);
	39	int ret;
	40
	41	pm_runtime_get_sync(&rt->dev);
	42
	43	if (!mutex_trylock(&rt->tb->lock)) {
	44	ret = restart_syscall();
	45	goto out;
	46	}
	47
8b02b2da	48	ret = tb_retimer_nvm_read(rt, offset, val, bytes);
dacb1287 KK	49	mutex_unlock(&rt->tb->lock);
	50
	51	out:
	52	pm_runtime_mark_last_busy(&rt->dev);
	53	pm_runtime_put_autosuspend(&rt->dev);
	54
	55	return ret;
	56	}
	57
8b02b2da	58	static int nvm_write(void priv, unsigned int offset, void val, size_t bytes)
dacb1287 KK	59	{
	60	struct tb_nvm *nvm = priv;
	61	struct tb_retimer *rt = tb_to_retimer(nvm->dev);
	62	int ret = 0;
	63
	64	if (!mutex_trylock(&rt->tb->lock))
	65	return restart_syscall();
	66
	67	ret = tb_nvm_write_buf(nvm, offset, val, bytes);
	68	mutex_unlock(&rt->tb->lock);
	69
	70	return ret;
	71	}
	72
	73	static int tb_retimer_nvm_add(struct tb_retimer *rt)
	74	{
	75	struct tb_nvm *nvm;
dacb1287 KK	76	int ret;
	77
	78	nvm = tb_nvm_alloc(&rt->dev);
aef9c693 SC	79	if (IS_ERR(nvm)) {
aef9c693 SC	80	ret = PTR_ERR(nvm) == -EOPNOTSUPP ? 0 : PTR_ERR(nvm);
dacb1287	81	goto err_nvm;
aef9c693	82	}
dacb1287	83
aef9c693	84	ret = tb_nvm_read_version(nvm);
dacb1287 KK	85	if (ret)
	86	goto err_nvm;
	87
aef9c693	88	ret = tb_nvm_add_active(nvm, nvm_read);
dacb1287 KK	89	if (ret)
	90	goto err_nvm;
	91
aef9c693	92	ret = tb_nvm_add_non_active(nvm, nvm_write);
dacb1287 KK	93	if (ret)
	94	goto err_nvm;
	95
	96	rt->nvm = nvm;
	97	return 0;
	98
	99	err_nvm:
aef9c693 SC	100	dev_dbg(&rt->dev, "NVM upgrade disabled\n");
	101	if (!IS_ERR(nvm))
	102	tb_nvm_free(nvm);
	103
dacb1287 KK	104	return ret;
	105	}
	106
	107	static int tb_retimer_nvm_validate_and_write(struct tb_retimer *rt)
	108	{
aef9c693 SC	109	unsigned int image_size;
aef9c693 SC	110	const u8 *buf;
faa1c615	111	int ret;
dacb1287	112
aef9c693 SC	113	ret = tb_nvm_validate(rt->nvm);
	114	if (ret)
	115	return ret;
dacb1287	116
aef9c693 SC	117	buf = rt->nvm->buf_data_start;
aef9c693 SC	118	image_size = rt->nvm->buf_data_size;
dacb1287	119
faa1c615 RM	120	ret = usb4_port_retimer_nvm_write(rt->port, rt->index, 0, buf,
faa1c615 RM	121	image_size);
aef9c693 SC	122	if (ret)
aef9c693 SC	123	return ret;
faa1c615	124
aef9c693 SC	125	rt->nvm->flushed = true;
aef9c693 SC	126	return 0;
faa1c615 RM	127	}
	128
	129	static int tb_retimer_nvm_authenticate(struct tb_retimer *rt, bool auth_only)
	130	{
25335b30	131	u32 status;
faa1c615 RM	132	int ret;
	133
	134	if (auth_only) {
	135	ret = usb4_port_retimer_nvm_set_offset(rt->port, rt->index, 0);
	136	if (ret)
	137	return ret;
	138	}
	139
25335b30 MW	140	ret = usb4_port_retimer_nvm_authenticate(rt->port, rt->index);
	141	if (ret)
	142	return ret;
	143
	144	usleep_range(100, 150);
	145
	146	/*
	147	* Check the status now if we still can access the retimer. It
	148	* is expected that the below fails.
	149	*/
	150	ret = usb4_port_retimer_nvm_authenticate_status(rt->port, rt->index,
	151	&status);
	152	if (!ret) {
	153	rt->auth_status = status;
	154	return status ? -EINVAL : 0;
	155	}
	156
	157	return 0;
dacb1287 KK	158	}
	159
	160	static ssize_t device_show(struct device dev, struct device_attribute attr,
	161	char *buf)
	162	{
	163	struct tb_retimer *rt = tb_to_retimer(dev);
	164
8283fb57	165	return sysfs_emit(buf, "%#x\n", rt->device);
dacb1287 KK	166	}
	167	static DEVICE_ATTR_RO(device);
	168
	169	static ssize_t nvm_authenticate_show(struct device *dev,
	170	struct device_attribute attr, char buf)
	171	{
	172	struct tb_retimer *rt = tb_to_retimer(dev);
	173	int ret;
	174
	175	if (!mutex_trylock(&rt->tb->lock))
	176	return restart_syscall();
	177
	178	if (!rt->nvm)
	179	ret = -EAGAIN;
aef9c693 SC	180	else if (rt->no_nvm_upgrade)
aef9c693 SC	181	ret = -EOPNOTSUPP;
dacb1287	182	else
8283fb57	183	ret = sysfs_emit(buf, "%#x\n", rt->auth_status);
dacb1287 KK	184
	185	mutex_unlock(&rt->tb->lock);
	186
	187	return ret;
	188	}
	189
cd0c1e58 GF	190	static void tb_retimer_set_inbound_sbtx(struct tb_port *port)
	191	{
	192	int i;
	193
	194	for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
	195	usb4_port_retimer_set_inbound_sbtx(port, i);
	196	}
	197
	198	static void tb_retimer_unset_inbound_sbtx(struct tb_port *port)
	199	{
	200	int i;
	201
	202	for (i = TB_MAX_RETIMER_INDEX; i >= 1; i--)
	203	usb4_port_retimer_unset_inbound_sbtx(port, i);
	204	}
	205
dacb1287 KK	206	static ssize_t nvm_authenticate_store(struct device *dev,
	207	struct device_attribute attr, const char buf, size_t count)
	208	{
	209	struct tb_retimer *rt = tb_to_retimer(dev);
faa1c615	210	int val, ret;
dacb1287 KK	211
	212	pm_runtime_get_sync(&rt->dev);
	213
	214	if (!mutex_trylock(&rt->tb->lock)) {
	215	ret = restart_syscall();
	216	goto exit_rpm;
	217	}
	218
	219	if (!rt->nvm) {
	220	ret = -EAGAIN;
	221	goto exit_unlock;
	222	}
	223
faa1c615	224	ret = kstrtoint(buf, 10, &val);
dacb1287 KK	225	if (ret)
	226	goto exit_unlock;
	227
	228	/* Always clear status */
	229	rt->auth_status = 0;
	230
	231	if (val) {
cd0c1e58	232	tb_retimer_set_inbound_sbtx(rt->port);
faa1c615 RM	233	if (val == AUTHENTICATE_ONLY) {
	234	ret = tb_retimer_nvm_authenticate(rt, true);
	235	} else {
	236	if (!rt->nvm->flushed) {
	237	if (!rt->nvm->buf) {
	238	ret = -EINVAL;
	239	goto exit_unlock;
	240	}
	241
	242	ret = tb_retimer_nvm_validate_and_write(rt);
	243	if (ret \|\| val == WRITE_ONLY)
	244	goto exit_unlock;
	245	}
	246	if (val == WRITE_AND_AUTHENTICATE)
	247	ret = tb_retimer_nvm_authenticate(rt, false);
dacb1287	248	}
dacb1287 KK	249	}
	250
	251	exit_unlock:
cd0c1e58	252	tb_retimer_unset_inbound_sbtx(rt->port);
dacb1287 KK	253	mutex_unlock(&rt->tb->lock);
	254	exit_rpm:
	255	pm_runtime_mark_last_busy(&rt->dev);
	256	pm_runtime_put_autosuspend(&rt->dev);
	257
	258	if (ret)
	259	return ret;
	260	return count;
	261	}
	262	static DEVICE_ATTR_RW(nvm_authenticate);
	263
	264	static ssize_t nvm_version_show(struct device *dev,
	265	struct device_attribute attr, char buf)
	266	{
	267	struct tb_retimer *rt = tb_to_retimer(dev);
	268	int ret;
	269
	270	if (!mutex_trylock(&rt->tb->lock))
	271	return restart_syscall();
	272
	273	if (!rt->nvm)
	274	ret = -EAGAIN;
	275	else
8283fb57	276	ret = sysfs_emit(buf, "%x.%x\n", rt->nvm->major, rt->nvm->minor);
dacb1287 KK	277
	278	mutex_unlock(&rt->tb->lock);
	279	return ret;
	280	}
	281	static DEVICE_ATTR_RO(nvm_version);
	282
	283	static ssize_t vendor_show(struct device dev, struct device_attribute attr,
	284	char *buf)
	285	{
	286	struct tb_retimer *rt = tb_to_retimer(dev);
	287
8283fb57	288	return sysfs_emit(buf, "%#x\n", rt->vendor);
dacb1287 KK	289	}
	290	static DEVICE_ATTR_RO(vendor);
	291
	292	static struct attribute *retimer_attrs[] = {
	293	&dev_attr_device.attr,
	294	&dev_attr_nvm_authenticate.attr,
	295	&dev_attr_nvm_version.attr,
	296	&dev_attr_vendor.attr,
	297	NULL
	298	};
	299
	300	static const struct attribute_group retimer_group = {
	301	.attrs = retimer_attrs,
	302	};
	303
	304	static const struct attribute_group *retimer_groups[] = {
	305	&retimer_group,
	306	NULL
	307	};
	308
	309	static void tb_retimer_release(struct device *dev)
	310	{
	311	struct tb_retimer *rt = tb_to_retimer(dev);
	312
	313	kfree(rt);
	314	}
	315
	316	struct device_type tb_retimer_type = {
	317	.name = "thunderbolt_retimer",
	318	.groups = retimer_groups,
	319	.release = tb_retimer_release,
	320	};
	321
	322	static int tb_retimer_add(struct tb_port *port, u8 index, u32 auth_status)
	323	{
	324	struct tb_retimer *rt;
	325	u32 vendor, device;
	326	int ret;
	327
dacb1287 KK	328	ret = usb4_port_retimer_read(port, index, USB4_SB_VENDOR_ID, &vendor,
	329	sizeof(vendor));
	330	if (ret) {
	331	if (ret != -ENODEV)
	332	tb_port_warn(port, "failed read retimer VendorId: %d\n", ret);
	333	return ret;
	334	}
	335
	336	ret = usb4_port_retimer_read(port, index, USB4_SB_PRODUCT_ID, &device,
	337	sizeof(device));
	338	if (ret) {
	339	if (ret != -ENODEV)
	340	tb_port_warn(port, "failed read retimer ProductId: %d\n", ret);
	341	return ret;
	342	}
	343
	344	if (vendor != PCI_VENDOR_ID_INTEL && vendor != 0x8087) {
	345	tb_port_info(port, "retimer NVM format of vendor %#x is not supported\n",
	346	vendor);
	347	return -EOPNOTSUPP;
	348	}
	349
	350	/*
	351	* Check that it supports NVM operations. If not then don't add
	352	* the device at all.
	353	*/
	354	ret = usb4_port_retimer_nvm_sector_size(port, index);
	355	if (ret < 0)
	356	return ret;
	357
	358	rt = kzalloc(sizeof(*rt), GFP_KERNEL);
	359	if (!rt)
	360	return -ENOMEM;
	361
	362	rt->index = index;
	363	rt->vendor = vendor;
	364	rt->device = device;
	365	rt->auth_status = auth_status;
	366	rt->port = port;
	367	rt->tb = port->sw->tb;
	368
1e56c88a	369	rt->dev.parent = &port->usb4->dev;
dacb1287 KK	370	rt->dev.bus = &tb_bus_type;
	371	rt->dev.type = &tb_retimer_type;
	372	dev_set_name(&rt->dev, "%s:%u.%u", dev_name(&port->sw->dev),
	373	port->port, index);
	374
	375	ret = device_register(&rt->dev);
	376	if (ret) {
	377	dev_err(&rt->dev, "failed to register retimer: %d\n", ret);
	378	put_device(&rt->dev);
	379	return ret;
	380	}
	381
	382	ret = tb_retimer_nvm_add(rt);
	383	if (ret) {
	384	dev_err(&rt->dev, "failed to add NVM devices: %d\n", ret);
bec4d7c9	385	device_unregister(&rt->dev);
dacb1287 KK	386	return ret;
	387	}
	388
	389	dev_info(&rt->dev, "new retimer found, vendor=%#x device=%#x\n",
	390	rt->vendor, rt->device);
	391
	392	pm_runtime_no_callbacks(&rt->dev);
	393	pm_runtime_set_active(&rt->dev);
	394	pm_runtime_enable(&rt->dev);
	395	pm_runtime_set_autosuspend_delay(&rt->dev, TB_AUTOSUSPEND_DELAY);
	396	pm_runtime_mark_last_busy(&rt->dev);
	397	pm_runtime_use_autosuspend(&rt->dev);
	398
	399	return 0;
	400	}
	401
	402	static void tb_retimer_remove(struct tb_retimer *rt)
	403	{
	404	dev_info(&rt->dev, "retimer disconnected\n");
	405	tb_nvm_free(rt->nvm);
	406	device_unregister(&rt->dev);
	407	}
	408
	409	struct tb_retimer_lookup {
	410	const struct tb_port *port;
	411	u8 index;
	412	};
	413
	414	static int retimer_match(struct device dev, void data)
	415	{
	416	const struct tb_retimer_lookup *lookup = data;
	417	struct tb_retimer *rt = tb_to_retimer(dev);
	418
	419	return rt && rt->port == lookup->port && rt->index == lookup->index;
	420	}
	421
	422	static struct tb_retimer tb_port_find_retimer(struct tb_port port, u8 index)
	423	{
	424	struct tb_retimer_lookup lookup = { .port = port, .index = index };
	425	struct device *dev;
	426
cae5f515	427	dev = device_find_child(&port->usb4->dev, &lookup, retimer_match);
dacb1287 KK	428	if (dev)
	429	return tb_to_retimer(dev);
	430
	431	return NULL;
	432	}
	433
	434	/**
	435	* tb_retimer_scan() - Scan for on-board retimers under port
	436	* @port: USB4 port to scan
3fb10ea4	437	* @add: If true also registers found retimers
dacb1287	438	*
3fb10ea4 RM	439	* Brings the sideband into a state where retimers can be accessed.
	440	* Then Tries to enumerate on-board retimers connected to @port. Found
	441	* retimers are registered as children of @port if @add is set. Does
	442	* not scan for cable retimers for now.
dacb1287	443	*/
3fb10ea4	444	int tb_retimer_scan(struct tb_port *port, bool add)
dacb1287	445	{
08fe7ae1	446	u32 status[TB_MAX_RETIMER_INDEX + 1] = {};
dacb1287 KK	447	int ret, i, last_idx = 0;
dacb1287 KK	448
dacb1287 KK	449	/*
	450	* Send broadcast RT to make sure retimer indices facing this
	451	* port are set.
	452	*/
	453	ret = usb4_port_enumerate_retimers(port);
	454	if (ret)
23257cfc	455	return ret;
dacb1287	456
3fb10ea4 RM	457	/*
	458	* Enable sideband channel for each retimer. We can do this
	459	* regardless whether there is device connected or not.
	460	*/
cd0c1e58	461	tb_retimer_set_inbound_sbtx(port);
3fb10ea4	462
dacb1287 KK	463	/*
	464	* Before doing anything else, read the authentication status.
	465	* If the retimer has it set, store it for the new retimer
	466	* device instance.
	467	*/
	468	for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++)
	469	usb4_port_retimer_nvm_authenticate_status(port, i, &status[i]);
	470
	471	for (i = 1; i <= TB_MAX_RETIMER_INDEX; i++) {
	472	/*
	473	* Last retimer is true only for the last on-board
	474	* retimer (the one connected directly to the Type-C
	475	* port).
	476	*/
	477	ret = usb4_port_retimer_is_last(port, i);
	478	if (ret > 0)
	479	last_idx = i;
	480	else if (ret < 0)
	481	break;
	482	}
	483
cd0c1e58 GF	484	tb_retimer_unset_inbound_sbtx(port);
cd0c1e58 GF	485
c28f3d80	486	if (!last_idx)
23257cfc	487	return 0;
dacb1287 KK	488
dacb1287 KK	489	/* Add on-board retimers if they do not exist already */
23257cfc	490	ret = 0;
dacb1287 KK	491	for (i = 1; i <= last_idx; i++) {
	492	struct tb_retimer *rt;
	493
	494	rt = tb_port_find_retimer(port, i);
	495	if (rt) {
	496	put_device(&rt->dev);
3fb10ea4	497	} else if (add) {
dacb1287 KK	498	ret = tb_retimer_add(port, i, status[i]);
dacb1287 KK	499	if (ret && ret != -EOPNOTSUPP)
3fb10ea4	500	break;
dacb1287 KK	501	}
	502	}
	503
1e56c88a	504	return ret;
dacb1287 KK	505	}
	506
	507	static int remove_retimer(struct device dev, void data)
	508	{
	509	struct tb_retimer *rt = tb_to_retimer(dev);
	510	struct tb_port *port = data;
	511
	512	if (rt && rt->port == port)
	513	tb_retimer_remove(rt);
	514	return 0;
	515	}
	516
	517	/**
	518	* tb_retimer_remove_all() - Remove all retimers under port
	519	* @port: USB4 port whose retimers to remove
	520	*
	521	* This removes all previously added retimers under @port.
	522	*/
	523	void tb_retimer_remove_all(struct tb_port *port)
	524	{
cae5f515 MW	525	struct usb4_port *usb4;
	526
	527	usb4 = port->usb4;
	528	if (usb4)
	529	device_for_each_child_reverse(&usb4->dev, port,
dacb1287 KK	530	remove_retimer);
dacb1287 KK	531	}