path: root/drivers/phy/tegra/xusb.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2014-2022, NVIDIA CORPORATION.  All rights reserved.
 */

#include <linux/delay.h>
#include <linux/io.h>
#include <linux/mailbox_client.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/phy/phy.h>
#include <linux/phy/tegra/xusb.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/reset.h>
#include <linux/slab.h>
#include <linux/workqueue.h>

#include <soc/tegra/fuse.h>

#include "xusb.h"

static struct phy *tegra_xusb_pad_of_xlate(struct device *dev,
					   struct of_phandle_args *args)
{
	struct tegra_xusb_pad *pad = dev_get_drvdata(dev);
	struct phy *phy = NULL;
	unsigned int i;

	if (args->args_count != 0)
		return ERR_PTR(-EINVAL);

	for (i = 0; i < pad->soc->num_lanes; i++) {
		if (!pad->lanes[i])
			continue;

		if (pad->lanes[i]->dev.of_node == args->np) {
			phy = pad->lanes[i];
			break;
		}
	}

	if (phy == NULL)
		phy = ERR_PTR(-ENODEV);

	return phy;
}

static const struct of_device_id tegra_xusb_padctl_of_match[] = {
#if defined(CONFIG_ARCH_TEGRA_124_SOC) || defined(CONFIG_ARCH_TEGRA_132_SOC)
	{
		.compatible = "nvidia,tegra124-xusb-padctl",
		.data = &tegra124_xusb_padctl_soc,
	},
#endif
#if defined(CONFIG_ARCH_TEGRA_210_SOC)
	{
		.compatible = "nvidia,tegra210-xusb-padctl",
		.data = &tegra210_xusb_padctl_soc,
	},
#endif
#if defined(CONFIG_ARCH_TEGRA_186_SOC)
	{
		.compatible = "nvidia,tegra186-xusb-padctl",
		.data = &tegra186_xusb_padctl_soc,
	},
#endif
#if defined(CONFIG_ARCH_TEGRA_194_SOC)
	{
		.compatible = "nvidia,tegra194-xusb-padctl",
		.data = &tegra194_xusb_padctl_soc,
	},
#endif
	{ }
};
MODULE_DEVICE_TABLE(of, tegra_xusb_padctl_of_match);

static struct device_node *
tegra_xusb_find_pad_node(struct tegra_xusb_padctl *padctl, const char *name)
{
	struct device_node *pads, *np;

	pads = of_get_child_by_name(padctl->dev->of_node, "pads");
	if (!pads)
		return NULL;

	np = of_get_child_by_name(pads, name);
	of_node_put(pads);

	return np;
}

static struct device_node *
tegra_xusb_pad_find_phy_node(struct tegra_xusb_pad *pad, unsigned int index)
{
	struct device_node *np, *lanes;

	lanes = of_get_child_by_name(pad->dev.of_node, "lanes");
	if (!lanes)
		return NULL;

	np = of_get_child_by_name(lanes, pad->soc->lanes[index].name);
	of_node_put(lanes);

	return np;
}

int tegra_xusb_lane_parse_dt(struct tegra_xusb_lane *lane,
			     struct device_node *np)
{
	struct device *dev = &lane->pad->dev;
	const char *function;
	int err;

	err = of_property_read_string(np, "nvidia,function", &function);
	if (err < 0)
		return err;

	err = match_string(lane->soc->funcs, lane->soc->num_funcs, function);
	if (err < 0) {
		dev_err(dev, "invalid function \"%s\" for lane \"%pOFn\"\n",
			function, np);
		return err;
	}

	lane->function = err;

	return 0;
}

static void tegra_xusb_lane_destroy(struct phy *phy)
{
	if (phy) {
		struct tegra_xusb_lane *lane = phy_get_drvdata(phy);

		lane->pad->ops->remove(lane);
		phy_destroy(phy);
	}
}

static void tegra_xusb_pad_release(struct device *dev)
{
	struct tegra_xusb_pad *pad = to_tegra_xusb_pad(dev);

	pad->soc->ops->remove(pad);
}

static const struct device_type tegra_xusb_pad_type = {
	.release = tegra_xusb_pad_release,
};

int tegra_xusb_pad_init(struct tegra_xusb_pad *pad,
			struct tegra_xusb_padctl *padctl,
			struct device_node *np)
{
	int err;

	device_initialize(&pad->dev);
	INIT_LIST_HEAD(&pad->list);
	pad->dev.parent = padctl->dev;
	pad->dev.type = &tegra_xusb_pad_type;
	pad->dev.of_node = np;
	pad->padctl = padctl;

	err = dev_set_name(&pad->dev, "%s", pad->soc->name);
	if (err < 0)
		goto unregister;

	err = device_add(&pad->dev);
	if (err < 0)
		goto unregister;

	return 0;

unregister:
	device_unregister(&pad->dev);
	return err;
}

int tegra_xusb_pad_register(struct tegra_xusb_pad *pad,
			    const struct phy_ops *ops)
{
	struct device_node *children;
	struct phy *lane;
	unsigned int i;
	int err;

	children = of_get_child_by_name(pad->dev.of_node, "lanes");
	if (!children)
		return -ENODEV;

	pad->lanes = devm_kcalloc(&pad->dev, pad->soc->num_lanes, sizeof(lane),
				  GFP_KERNEL);
	if (!pad->lanes) {
		of_node_put(children);
		return -ENOMEM;
	}

	for (i = 0; i < pad->soc->num_lanes; i++) {
		struct device_node *np = tegra_xusb_pad_find_phy_node(pad, i);
		struct tegra_xusb_lane *lane;

		/* skip disabled lanes */
		if (!np || !of_device_is_available(np)) {
			of_node_put(np);
			continue;
		}

		pad->lanes[i] = phy_create(&pad->dev, np, ops);
		if (IS_ERR(pad->lanes[i])) {
			err = PTR_ERR(pad->lanes[i]);
			of_node_put(np);
			goto remove;
		}

		lane = pad->ops->probe(pad, np, i);
		if (IS_ERR(lane)) {
			phy_destroy(pad->lanes[i]);
			err = PTR_ERR(lane);
			goto remove;
		}

		list_add_tail(&lane->list, &pad->padctl->lanes);
		phy_set_drvdata(pad->lanes[i], lane);
	}

	pad->provider = of_phy_provider_register_full(&pad->dev, children,
						      tegra_xusb_pad_of_xlate);
	if (IS_ERR(pad->provider)) {
		err = PTR_ERR(pad->provider);
		goto remove;
	}

	return 0;

remove:
	while (i--)
		tegra_xusb_lane_destroy(pad->lanes[i]);

	of_node_put(children);

	return err;
}

void tegra_xusb_pad_unregister(struct tegra_xusb_pad *pad)
{
	unsigned int i = pad->soc->num_lanes;

	of_phy_provider_unregister(pad->provider);

	while (i--)
		tegra_xusb_lane_destroy(pad->lanes[i]);

	device_unregister(&pad->dev);
}

static struct tegra_xusb_pad *
tegra_xusb_pad_create(struct tegra_xusb_padctl *padctl,
		      const struct tegra_xusb_pad_soc *soc)
{
	struct tegra_xusb_pad *pad;
	struct device_node *np;
	int err;

	np = tegra_xusb_find_pad_node(padctl, soc->name);
	if (!np || !of_device_is_available(np))
		return NULL;

	pad = soc->ops->probe(padctl, soc, np);
	if (IS_ERR(pad)) {
		err = PTR_ERR(pad);
		dev_err(padctl->dev, "failed to create pad %s: %d\n",
			soc->name, err);
		return ERR_PTR(err);
	}

	/* XXX move this into ->probe() to avoid string comparison */
	if (strcmp(soc->name, "pcie") == 0)
		padctl->pcie = pad;

	if (strcmp(soc->name, "sata") == 0)
		padctl->sata = pad;

	if (strcmp(soc->name, "usb2") == 0)
		padctl->usb2 = pad;

	if (strcmp(soc->name, "ulpi") == 0)
		padctl->ulpi = pad;

	if (strcmp(soc->name, "hsic") == 0)
		padctl->hsic = pad;

	return pad;
}

static void __tegra_xusb_remove_pads(struct tegra_xusb_padctl *padctl)
{
	struct tegra_xusb_pad *pad, *tmp;

	list_for_each_entry_safe_reverse(pad, tmp, &padctl->pads, list) {
		list_del(&pad->list);
		tegra_xusb_pad_unregister(pad);
	}
}

static void tegra_xusb_remove_pads(struct tegra_xusb_padctl *padctl)
{
	mutex_lock(&padctl->lock);
	__tegra_xusb_remove_pads(padctl);
	mutex_unlock(&padctl->lock);
}

static void tegra_xusb_lane_program(struct tegra_xusb_lane *lane)
{
	struct tegra_xusb_padctl *padctl = lane->pad->padctl;
	const struct tegra_xusb_lan