root/drivers/phy/broadcom/phy-brcm-usb.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * phy-brcm-usb.c - Broadcom USB Phy Driver
 *
 * Copyright (C) 2015-2017 Broadcom
 */

#include <linux/clk.h>
#include <linux/delay.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/phy/phy.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/soc/brcmstb/brcmstb.h>
#include <dt-bindings/phy/phy.h>
#include <linux/mfd/syscon.h>
#include <linux/suspend.h>

#include "phy-brcm-usb-init.h"

static DEFINE_MUTEX(sysfs_lock);

enum brcm_usb_phy_id {
        BRCM_USB_PHY_2_0 = 0,
        BRCM_USB_PHY_3_0,
        BRCM_USB_PHY_ID_MAX
};

struct value_to_name_map {
        int value;
        const char *name;
};

struct match_chip_info {
        void (*init_func)(struct brcm_usb_init_params *params);
        u8 required_regs[BRCM_REGS_MAX + 1];
        u8 optional_reg;
};

static const struct value_to_name_map brcm_dr_mode_to_name[] = {
        { USB_CTLR_MODE_HOST, "host" },
        { USB_CTLR_MODE_DEVICE, "peripheral" },
        { USB_CTLR_MODE_DRD, "drd" },
        { USB_CTLR_MODE_TYPEC_PD, "typec-pd" }
};

static const struct value_to_name_map brcm_dual_mode_to_name[] = {
        { 0, "host" },
        { 1, "device" },
        { 2, "auto" },
};

struct brcm_usb_phy {
        struct phy *phy;
        unsigned int id;
        bool inited;
};

struct brcm_usb_phy_data {
        struct  brcm_usb_init_params ini;
        bool                    has_eohci;
        bool                    has_xhci;
        struct clk              *usb_20_clk;
        struct clk              *usb_30_clk;
        struct clk              *suspend_clk;
        struct mutex            mutex;  /* serialize phy init */
        int                     init_count;
        int                     wake_irq;
        struct brcm_usb_phy     phys[BRCM_USB_PHY_ID_MAX];
        struct notifier_block   pm_notifier;
        bool                    pm_active;
};

static s8 *node_reg_names[BRCM_REGS_MAX] = {
        "crtl", "xhci_ec", "xhci_gbl", "usb_phy", "usb_mdio", "bdc_ec"
};

static int brcm_pm_notifier(struct notifier_block *notifier,
                            unsigned long pm_event,
                            void *unused)
{
        struct brcm_usb_phy_data *priv =
                container_of(notifier, struct brcm_usb_phy_data, pm_notifier);

        switch (pm_event) {
        case PM_HIBERNATION_PREPARE:
        case PM_SUSPEND_PREPARE:
                priv->pm_active = true;
                break;
        case PM_POST_RESTORE:
        case PM_POST_HIBERNATION:
        case PM_POST_SUSPEND:
                priv->pm_active = false;
                break;
        }
        return NOTIFY_DONE;
}

static irqreturn_t brcm_usb_phy_wake_isr(int irq, void *dev_id)
{
        struct device *dev = dev_id;

        pm_wakeup_event(dev, 0);

        return IRQ_HANDLED;
}

static int brcm_usb_phy_init(struct phy *gphy)
{
        struct brcm_usb_phy *phy = phy_get_drvdata(gphy);
        struct brcm_usb_phy_data *priv =
                container_of(phy, struct brcm_usb_phy_data, phys[phy->id]);

        if (priv->pm_active)
                return 0;

        /*
         * Use a lock to make sure a second caller waits until
         * the base phy is inited before using it.
         */
        mutex_lock(&priv->mutex);
        if (priv->init_count++ == 0) {
                clk_prepare_enable(priv->usb_20_clk);
                clk_prepare_enable(priv->usb_30_clk);
                clk_prepare_enable(priv->suspend_clk);
                brcm_usb_init_common(&priv->ini);
        }
        mutex_unlock(&priv->mutex);
        if (phy->id == BRCM_USB_PHY_2_0)
                brcm_usb_init_eohci(&priv->ini);
        else if (phy->id == BRCM_USB_PHY_3_0)
                brcm_usb_init_xhci(&priv->ini);
        phy->inited = true;
        dev_dbg(&gphy->dev, "INIT, id: %d, total: %d\n", phy->id,
                priv->init_count);

        return 0;
}

static int brcm_usb_phy_exit(struct phy *gphy)
{
        struct brcm_usb_phy *phy = phy_get_drvdata(gphy);
        struct brcm_usb_phy_data *priv =
                container_of(phy, struct brcm_usb_phy_data, phys[phy->id]);

        if (priv->pm_active)
                return 0;

        dev_dbg(&gphy->dev, "EXIT\n");
        if (phy->id == BRCM_USB_PHY_2_0)
                brcm_usb_uninit_eohci(&priv->ini);
        if (phy->id == BRCM_USB_PHY_3_0)
                brcm_usb_uninit_xhci(&priv->ini);

        /* If both xhci and eohci are gone, reset everything else */
        mutex_lock(&priv->mutex);
        if (--priv->init_count == 0) {
                brcm_usb_uninit_common(&priv->ini);
                clk_disable_unprepare(priv->usb_20_clk);
                clk_disable_unprepare(priv->usb_30_clk);
                clk_disable_unprepare(priv->suspend_clk);
        }
        mutex_unlock(&priv->mutex);
        phy->inited = false;
        return 0;
}

static const struct phy_ops brcm_usb_phy_ops = {
        .init           = brcm_usb_phy_init,
        .exit           = brcm_usb_phy_exit,
        .owner          = THIS_MODULE,
};

static struct phy *brcm_usb_phy_xlate(struct device *dev,
                                      const struct of_phandle_args *args)
{
        struct brcm_usb_phy_data *data = dev_get_drvdata(dev);

        /*
         * values 0 and 1 are for backward compatibility with
         * device tree nodes from older bootloaders.
         */
        switch (args->args[0]) {
        case 0:
        case PHY_TYPE_USB2:
                if (data->phys[BRCM_USB_PHY_2_0].phy)
                        return data->phys[BRCM_USB_PHY_2_0].phy;
                dev_warn(dev, "Error, 2.0 Phy not found\n");
                break;
        case 1:
        case PHY_TYPE_USB3:
                if (data->phys[BRCM_USB_PHY_3_0].phy)
                        return data->phys[BRCM_USB_PHY_3_0].phy;
                dev_warn(dev, "Error, 3.0 Phy not found\n");
                break;
        }
        return ERR_PTR(-ENODEV);
}

static int name_to_value(const struct value_to_name_map *table, int count,
                         const char *name, int *value)
{
        int x;

        *value = 0;
        for (x = 0; x < count; x++) {
                if (sysfs_streq(name, table[x].name)) {
                        *value = x;
                        return 0;
                }
        }
        return -EINVAL;
}

static const char *value_to_name(const struct value_to_name_map *table, int count,
                                 int value)
{
        if (value >= count)
                return "unknown";
        return table[value].name;
}

static ssize_t dr_mode_show(struct device *dev,
                            struct device_attribute *attr,
                            char *buf)
{
        struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);

        return sprintf(buf, "%s\n",
                value_to_name(&brcm_dr_mode_to_name[0],
                              ARRAY_SIZE(brcm_dr_mode_to_name),
                              priv->ini.supported_port_modes));
}
static DEVICE_ATTR_RO(dr_mode);

static ssize_t dual_select_store(struct device *dev,
                                 struct device_attribute *attr,
                                 const char *buf, size_t len)
{
        struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
        int value;
        int res;

        mutex_lock(&sysfs_lock);
        res = name_to_value(&brcm_dual_mode_to_name[0],
                            ARRAY_SIZE(brcm_dual_mode_to_name), buf, &value);
        if (!res) {
                priv->ini.port_mode = value;
                brcm_usb_set_dual_select(&priv->ini);
                res = len;
        }
        mutex_unlock(&sysfs_lock);
        return res;
}

static ssize_t dual_select_show(struct device *dev,
                                struct device_attribute *attr,
                                char *buf)
{
        struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);
        int value;

        mutex_lock(&sysfs_lock);
        value = brcm_usb_get_dual_select(&priv->ini);
        mutex_unlock(&sysfs_lock);
        return sprintf(buf, "%s\n",
                value_to_name(&brcm_dual_mode_to_name[0],
                              ARRAY_SIZE(brcm_dual_mode_to_name),
                              value));
}
static DEVICE_ATTR_RW(dual_select);

static struct attribute *brcm_usb_phy_attrs[] = {
        &dev_attr_dr_mode.attr,
        &dev_attr_dual_select.attr,
        NULL
};

static const struct attribute_group brcm_usb_phy_group = {
        .attrs = brcm_usb_phy_attrs,
};

static const struct match_chip_info chip_info_74110 = {
        .init_func = &brcm_usb_dvr_init_74110,
        .required_regs = {
                BRCM_REGS_CTRL,
                BRCM_REGS_XHCI_EC,
                BRCM_REGS_XHCI_GBL,
                -1,
        },
};

static const struct match_chip_info chip_info_4908 = {
        .init_func = &brcm_usb_dvr_init_4908,
        .required_regs = {
                BRCM_REGS_CTRL,
                BRCM_REGS_XHCI_EC,
                -1,
        },
};

static const struct match_chip_info chip_info_7216 = {
        .init_func = &brcm_usb_dvr_init_7216,
        .required_regs = {
                BRCM_REGS_CTRL,
                BRCM_REGS_XHCI_EC,
                BRCM_REGS_XHCI_GBL,
                -1,
        },
};

static const struct match_chip_info chip_info_7211b0 = {
        .init_func = &brcm_usb_dvr_init_7211b0,
        .required_regs = {
                BRCM_REGS_CTRL,
                BRCM_REGS_XHCI_EC,
                BRCM_REGS_XHCI_GBL,
                BRCM_REGS_USB_PHY,
                BRCM_REGS_USB_MDIO,
                -1,
        },
        .optional_reg = BRCM_REGS_BDC_EC,
};

static const struct match_chip_info chip_info_7445 = {
        .init_func = &brcm_usb_dvr_init_7445,
        .required_regs = {
                BRCM_REGS_CTRL,
                BRCM_REGS_XHCI_EC,
                -1,
        },
};

static const struct of_device_id brcm_usb_dt_ids[] = {
        {
                .compatible = "brcm,bcm74110-usb-phy",
                .data = &chip_info_74110,
        },
        {
                .compatible = "brcm,bcm4908-usb-phy",
                .data = &chip_info_4908,
        },
        {
                .compatible = "brcm,bcm7216-usb-phy",
                .data = &chip_info_7216,
        },
        {
                .compatible = "brcm,bcm7211-usb-phy",
                .data = &chip_info_7211b0,
        },
        {
                .compatible = "brcm,brcmstb-usb-phy",
                .data = &chip_info_7445,
        },
        { /* sentinel */ }
};

static int brcm_usb_get_regs(struct platform_device *pdev,
                             enum brcmusb_reg_sel regs,
                             struct  brcm_usb_init_params *ini,
                             bool optional)
{
        struct resource *res;

        /* Older DT nodes have ctrl and optional xhci_ec by index only */
        res = platform_get_resource_byname(pdev, IORESOURCE_MEM,
                                                node_reg_names[regs]);
        if (res == NULL) {
                if (regs == BRCM_REGS_CTRL) {
                        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
                } else if (regs == BRCM_REGS_XHCI_EC) {
                        res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
                        /* XHCI_EC registers are optional */
                        if (res == NULL)
                                return 0;
                }
                if (res == NULL) {
                        if (optional) {
                                dev_dbg(&pdev->dev,
                                        "Optional reg %s not found\n",
                                        node_reg_names[regs]);
                                return 0;
                        }
                        dev_err(&pdev->dev, "can't get %s base addr\n",
                                node_reg_names[regs]);
                        return 1;
                }
        }
        ini->regs[regs] = devm_ioremap_resource(&pdev->dev, res);
        if (IS_ERR(ini->regs[regs])) {
                dev_err(&pdev->dev, "can't map %s register space\n",
                        node_reg_names[regs]);
                return 1;
        }
        return 0;
}

static int brcm_usb_phy_dvr_init(struct platform_device *pdev,
                                 struct brcm_usb_phy_data *priv,
                                 struct device_node *dn)
{
        struct device *dev = &pdev->dev;
        struct phy *gphy = NULL;
        int err;

        priv->usb_20_clk = of_clk_get_by_name(dn, "sw_usb");
        if (IS_ERR(priv->usb_20_clk)) {
                if (PTR_ERR(priv->usb_20_clk) == -EPROBE_DEFER)
                        return -EPROBE_DEFER;
                dev_info(dev, "Clock not found in Device Tree\n");
                priv->usb_20_clk = NULL;
        }
        err = clk_prepare_enable(priv->usb_20_clk);
        if (err)
                return err;

        if (priv->has_eohci) {
                gphy = devm_phy_create(dev, NULL, &brcm_usb_phy_ops);
                if (IS_ERR(gphy)) {
                        dev_err(dev, "failed to create EHCI/OHCI PHY\n");
                        return PTR_ERR(gphy);
                }
                priv->phys[BRCM_USB_PHY_2_0].phy = gphy;
                priv->phys[BRCM_USB_PHY_2_0].id = BRCM_USB_PHY_2_0;
                phy_set_drvdata(gphy, &priv->phys[BRCM_USB_PHY_2_0]);
        }

        if (priv->has_xhci) {
                gphy = devm_phy_create(dev, NULL, &brcm_usb_phy_ops);
                if (IS_ERR(gphy)) {
                        dev_err(dev, "failed to create XHCI PHY\n");
                        return PTR_ERR(gphy);
                }
                priv->phys[BRCM_USB_PHY_3_0].phy = gphy;
                priv->phys[BRCM_USB_PHY_3_0].id = BRCM_USB_PHY_3_0;
                phy_set_drvdata(gphy, &priv->phys[BRCM_USB_PHY_3_0]);

                priv->usb_30_clk = of_clk_get_by_name(dn, "sw_usb3");
                if (IS_ERR(priv->usb_30_clk)) {
                        if (PTR_ERR(priv->usb_30_clk) == -EPROBE_DEFER)
                                return -EPROBE_DEFER;
                        dev_info(dev,
                                 "USB3.0 clock not found in Device Tree\n");
                        priv->usb_30_clk = NULL;
                }
                err = clk_prepare_enable(priv->usb_30_clk);
                if (err)
                        return err;
        }

        priv->suspend_clk = clk_get(dev, "usb0_freerun");
        if (IS_ERR(priv->suspend_clk)) {
                if (PTR_ERR(priv->suspend_clk) == -EPROBE_DEFER)
                        return -EPROBE_DEFER;
                dev_err(dev, "Suspend Clock not found in Device Tree\n");
                priv->suspend_clk = NULL;
        }

        priv->wake_irq = platform_get_irq_byname_optional(pdev, "wake");
        if (priv->wake_irq < 0)
                priv->wake_irq = platform_get_irq_byname_optional(pdev, "wakeup");
        if (priv->wake_irq >= 0) {
                err = devm_request_irq(dev, priv->wake_irq,
                                       brcm_usb_phy_wake_isr, 0,
                                       dev_name(dev), dev);
                if (err < 0)
                        return err;
                device_set_wakeup_capable(dev, 1);
        } else {
                dev_info(dev,
                         "Wake interrupt missing, system wake not supported\n");
        }

        return 0;
}

static int brcm_usb_phy_probe(struct platform_device *pdev)
{
        struct device *dev = &pdev->dev;
        struct brcm_usb_phy_data *priv;
        struct phy_provider *phy_provider;
        struct device_node *dn = pdev->dev.of_node;
        int err;
        const char *mode;
        const struct match_chip_info *info;
        struct regmap *rmap;
        int x;

        priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
        if (!priv)
                return -ENOMEM;
        platform_set_drvdata(pdev, priv);

        priv->ini.family_id = brcmstb_get_family_id();
        priv->ini.product_id = brcmstb_get_product_id();

        info = of_device_get_match_data(&pdev->dev);
        if (!info)
                return -ENOENT;

        info->init_func(&priv->ini);

        dev_dbg(dev, "Best mapping table is for %s\n",
                priv->ini.family_name);

        of_property_read_u32(dn, "brcm,ipp", &priv->ini.ipp);
        of_property_read_u32(dn, "brcm,ioc", &priv->ini.ioc);

        priv->ini.supported_port_modes = USB_CTLR_MODE_HOST;
        err = of_property_read_string(dn, "dr_mode", &mode);
        if (err == 0) {
                name_to_value(&brcm_dr_mode_to_name[0],
                              ARRAY_SIZE(brcm_dr_mode_to_name),
                        mode, &priv->ini.supported_port_modes);
        }
        /* Default port_mode to supported port_modes */
        priv->ini.port_mode = priv->ini.supported_port_modes;

        if (of_property_read_bool(dn, "brcm,has-xhci"))
                priv->has_xhci = true;
        if (of_property_read_bool(dn, "brcm,has-eohci"))
                priv->has_eohci = true;

        for (x = 0; x < BRCM_REGS_MAX; x++) {
                if (info->required_regs[x] >= BRCM_REGS_MAX)
                        break;

                err = brcm_usb_get_regs(pdev, info->required_regs[x],
                                        &priv->ini, false);
                if (err)
                        return -EINVAL;
        }
        if (info->optional_reg) {
                err = brcm_usb_get_regs(pdev, info->optional_reg,
                                        &priv->ini, true);
                if (err)
                        return -EINVAL;
        }

        err = brcm_usb_phy_dvr_init(pdev, priv, dn);
        if (err)
                return err;

        priv->pm_notifier.notifier_call = brcm_pm_notifier;
        register_pm_notifier(&priv->pm_notifier);

        mutex_init(&priv->mutex);

        /* make sure invert settings are correct */
        brcm_usb_init_ipp(&priv->ini);

        /*
         * Create sysfs entries for mode.
         * Remove "dual_select" attribute if not in dual mode
         */
        if (priv->ini.supported_port_modes != USB_CTLR_MODE_DRD)
                brcm_usb_phy_attrs[1] = NULL;
        err = sysfs_create_group(&dev->kobj, &brcm_usb_phy_group);
        if (err)
                dev_warn(dev, "Error creating sysfs attributes\n");

        /* Get piarbctl syscon if it exists */
        rmap = syscon_regmap_lookup_by_phandle(dev->of_node,
                                                 "syscon-piarbctl");
        if (IS_ERR(rmap))
                rmap = syscon_regmap_lookup_by_phandle(dev->of_node,
                                                       "brcm,syscon-piarbctl");
        if (!IS_ERR(rmap))
                priv->ini.syscon_piarbctl = rmap;

        /* start with everything off */
        if (priv->has_xhci)
                brcm_usb_uninit_xhci(&priv->ini);
        if (priv->has_eohci)
                brcm_usb_uninit_eohci(&priv->ini);
        brcm_usb_uninit_common(&priv->ini);
        clk_disable_unprepare(priv->usb_20_clk);
        clk_disable_unprepare(priv->usb_30_clk);

        phy_provider = devm_of_phy_provider_register(dev, brcm_usb_phy_xlate);

        return PTR_ERR_OR_ZERO(phy_provider);
}

static void brcm_usb_phy_remove(struct platform_device *pdev)
{
        struct brcm_usb_phy_data *priv = dev_get_drvdata(&pdev->dev);

        sysfs_remove_group(&pdev->dev.kobj, &brcm_usb_phy_group);
        unregister_pm_notifier(&priv->pm_notifier);
}

#ifdef CONFIG_PM_SLEEP
static int brcm_usb_phy_suspend(struct device *dev)
{
        struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);

        if (priv->init_count) {
                dev_dbg(dev, "SUSPEND\n");
                priv->ini.wake_enabled = device_may_wakeup(dev);
                if (priv->phys[BRCM_USB_PHY_3_0].inited)
                        brcm_usb_uninit_xhci(&priv->ini);
                if (priv->phys[BRCM_USB_PHY_2_0].inited)
                        brcm_usb_uninit_eohci(&priv->ini);
                brcm_usb_uninit_common(&priv->ini);

                /*
                 * Handle the clocks unless needed for wake. This has
                 * to work for both older XHCI->3.0-clks, EOHCI->2.0-clks
                 * and newer XHCI->2.0-clks/3.0-clks.
                 */

                if (!priv->ini.wake_enabled) {
                        if (priv->phys[BRCM_USB_PHY_3_0].inited)
                                clk_disable_unprepare(priv->usb_30_clk);
                        if (priv->phys[BRCM_USB_PHY_2_0].inited ||
                            !priv->has_eohci)
                                clk_disable_unprepare(priv->usb_20_clk);
                }
                if (priv->wake_irq >= 0)
                        enable_irq_wake(priv->wake_irq);
        }
        return 0;
}

static int brcm_usb_phy_resume(struct device *dev)
{
        struct brcm_usb_phy_data *priv = dev_get_drvdata(dev);

        if (!priv->ini.wake_enabled) {
                clk_prepare_enable(priv->usb_20_clk);
                clk_prepare_enable(priv->usb_30_clk);
        }
        brcm_usb_init_ipp(&priv->ini);

        /*
         * Initialize anything that was previously initialized.
         * Uninitialize anything that wasn't previously initialized.
         */
        if (priv->init_count) {
                dev_dbg(dev, "RESUME\n");
                if (priv->wake_irq >= 0)
                        disable_irq_wake(priv->wake_irq);
                brcm_usb_init_common(&priv->ini);
                if (priv->phys[BRCM_USB_PHY_2_0].inited) {
                        brcm_usb_init_eohci(&priv->ini);
                } else if (priv->has_eohci) {
                        brcm_usb_uninit_eohci(&priv->ini);
                        clk_disable_unprepare(priv->usb_20_clk);
                }
                if (priv->phys[BRCM_USB_PHY_3_0].inited) {
                        brcm_usb_init_xhci(&priv->ini);
                } else if (priv->has_xhci) {
                        brcm_usb_uninit_xhci(&priv->ini);
                        clk_disable_unprepare(priv->usb_30_clk);
                        if (!priv->has_eohci)
                                clk_disable_unprepare(priv->usb_20_clk);
                }
        } else {
                if (priv->has_xhci)
                        brcm_usb_uninit_xhci(&priv->ini);
                if (priv->has_eohci)
                        brcm_usb_uninit_eohci(&priv->ini);
                brcm_usb_uninit_common(&priv->ini);
                clk_disable_unprepare(priv->usb_20_clk);
                clk_disable_unprepare(priv->usb_30_clk);
        }
        priv->ini.wake_enabled = false;
        return 0;
}
#endif /* CONFIG_PM_SLEEP */

static const struct dev_pm_ops brcm_usb_phy_pm_ops = {
        SET_LATE_SYSTEM_SLEEP_PM_OPS(brcm_usb_phy_suspend, brcm_usb_phy_resume)
};

MODULE_DEVICE_TABLE(of, brcm_usb_dt_ids);

static struct platform_driver brcm_usb_driver = {
        .probe          = brcm_usb_phy_probe,
        .remove         = brcm_usb_phy_remove,
        .driver         = {
                .name   = "brcmstb-usb-phy",
                .pm = &brcm_usb_phy_pm_ops,
                .of_match_table = brcm_usb_dt_ids,
        },
};

module_platform_driver(brcm_usb_driver);

MODULE_AUTHOR("Al Cooper <acooper@broadcom.com>");
MODULE_DESCRIPTION("BRCM USB PHY driver");
MODULE_LICENSE("GPL v2");