linux/drivers/phy/renesas/phy-rcar-gen2.c
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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * Renesas R-Car Gen2 PHY driver
   4 *
   5 * Copyright (C) 2014 Renesas Solutions Corp.
   6 * Copyright (C) 2014 Cogent Embedded, Inc.
   7 * Copyright (C) 2019 Renesas Electronics Corp.
   8 */
   9
  10#include <linux/clk.h>
  11#include <linux/delay.h>
  12#include <linux/io.h>
  13#include <linux/module.h>
  14#include <linux/of.h>
  15#include <linux/phy/phy.h>
  16#include <linux/platform_device.h>
  17#include <linux/spinlock.h>
  18#include <linux/atomic.h>
  19#include <linux/of_device.h>
  20
  21#define USBHS_LPSTS                     0x02
  22#define USBHS_UGCTRL                    0x80
  23#define USBHS_UGCTRL2                   0x84
  24#define USBHS_UGSTS                     0x88    /* From technical update */
  25
  26/* Low Power Status register (LPSTS) */
  27#define USBHS_LPSTS_SUSPM               0x4000
  28
  29/* USB General control register (UGCTRL) */
  30#define USBHS_UGCTRL_CONNECT            0x00000004
  31#define USBHS_UGCTRL_PLLRESET           0x00000001
  32
  33/* USB General control register 2 (UGCTRL2) */
  34#define USBHS_UGCTRL2_USB2SEL           0x80000000
  35#define USBHS_UGCTRL2_USB2SEL_PCI       0x00000000
  36#define USBHS_UGCTRL2_USB2SEL_USB30     0x80000000
  37#define USBHS_UGCTRL2_USB0SEL           0x00000030
  38#define USBHS_UGCTRL2_USB0SEL_PCI       0x00000010
  39#define USBHS_UGCTRL2_USB0SEL_HS_USB    0x00000030
  40#define USBHS_UGCTRL2_USB0SEL_USB20     0x00000010
  41#define USBHS_UGCTRL2_USB0SEL_HS_USB20  0x00000020
  42
  43/* USB General status register (UGSTS) */
  44#define USBHS_UGSTS_LOCK                0x00000100 /* From technical update */
  45
  46#define PHYS_PER_CHANNEL        2
  47
  48struct rcar_gen2_phy {
  49        struct phy *phy;
  50        struct rcar_gen2_channel *channel;
  51        int number;
  52        u32 select_value;
  53};
  54
  55struct rcar_gen2_channel {
  56        struct device_node *of_node;
  57        struct rcar_gen2_phy_driver *drv;
  58        struct rcar_gen2_phy phys[PHYS_PER_CHANNEL];
  59        int selected_phy;
  60        u32 select_mask;
  61};
  62
  63struct rcar_gen2_phy_driver {
  64        void __iomem *base;
  65        struct clk *clk;
  66        spinlock_t lock;
  67        int num_channels;
  68        struct rcar_gen2_channel *channels;
  69};
  70
  71struct rcar_gen2_phy_data {
  72        const struct phy_ops *gen2_phy_ops;
  73        const u32 (*select_value)[PHYS_PER_CHANNEL];
  74        const u32 num_channels;
  75};
  76
  77static int rcar_gen2_phy_init(struct phy *p)
  78{
  79        struct rcar_gen2_phy *phy = phy_get_drvdata(p);
  80        struct rcar_gen2_channel *channel = phy->channel;
  81        struct rcar_gen2_phy_driver *drv = channel->drv;
  82        unsigned long flags;
  83        u32 ugctrl2;
  84
  85        /*
  86         * Try to acquire exclusive access to PHY.  The first driver calling
  87         * phy_init()  on a given channel wins, and all attempts  to use another
  88         * PHY on this channel will fail until phy_exit() is called by the first
  89         * driver.   Achieving this with cmpxcgh() should be SMP-safe.
  90         */
  91        if (cmpxchg(&channel->selected_phy, -1, phy->number) != -1)
  92                return -EBUSY;
  93
  94        clk_prepare_enable(drv->clk);
  95
  96        spin_lock_irqsave(&drv->lock, flags);
  97        ugctrl2 = readl(drv->base + USBHS_UGCTRL2);
  98        ugctrl2 &= ~channel->select_mask;
  99        ugctrl2 |= phy->select_value;
 100        writel(ugctrl2, drv->base + USBHS_UGCTRL2);
 101        spin_unlock_irqrestore(&drv->lock, flags);
 102        return 0;
 103}
 104
 105static int rcar_gen2_phy_exit(struct phy *p)
 106{
 107        struct rcar_gen2_phy *phy = phy_get_drvdata(p);
 108        struct rcar_gen2_channel *channel = phy->channel;
 109
 110        clk_disable_unprepare(channel->drv->clk);
 111
 112        channel->selected_phy = -1;
 113
 114        return 0;
 115}
 116
 117static int rcar_gen2_phy_power_on(struct phy *p)
 118{
 119        struct rcar_gen2_phy *phy = phy_get_drvdata(p);
 120        struct rcar_gen2_phy_driver *drv = phy->channel->drv;
 121        void __iomem *base = drv->base;
 122        unsigned long flags;
 123        u32 value;
 124        int err = 0, i;
 125
 126        /* Skip if it's not USBHS */
 127        if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB)
 128                return 0;
 129
 130        spin_lock_irqsave(&drv->lock, flags);
 131
 132        /* Power on USBHS PHY */
 133        value = readl(base + USBHS_UGCTRL);
 134        value &= ~USBHS_UGCTRL_PLLRESET;
 135        writel(value, base + USBHS_UGCTRL);
 136
 137        value = readw(base + USBHS_LPSTS);
 138        value |= USBHS_LPSTS_SUSPM;
 139        writew(value, base + USBHS_LPSTS);
 140
 141        for (i = 0; i < 20; i++) {
 142                value = readl(base + USBHS_UGSTS);
 143                if ((value & USBHS_UGSTS_LOCK) == USBHS_UGSTS_LOCK) {
 144                        value = readl(base + USBHS_UGCTRL);
 145                        value |= USBHS_UGCTRL_CONNECT;
 146                        writel(value, base + USBHS_UGCTRL);
 147                        goto out;
 148                }
 149                udelay(1);
 150        }
 151
 152        /* Timed out waiting for the PLL lock */
 153        err = -ETIMEDOUT;
 154
 155out:
 156        spin_unlock_irqrestore(&drv->lock, flags);
 157
 158        return err;
 159}
 160
 161static int rcar_gen2_phy_power_off(struct phy *p)
 162{
 163        struct rcar_gen2_phy *phy = phy_get_drvdata(p);
 164        struct rcar_gen2_phy_driver *drv = phy->channel->drv;
 165        void __iomem *base = drv->base;
 166        unsigned long flags;
 167        u32 value;
 168
 169        /* Skip if it's not USBHS */
 170        if (phy->select_value != USBHS_UGCTRL2_USB0SEL_HS_USB)
 171                return 0;
 172
 173        spin_lock_irqsave(&drv->lock, flags);
 174
 175        /* Power off USBHS PHY */
 176        value = readl(base + USBHS_UGCTRL);
 177        value &= ~USBHS_UGCTRL_CONNECT;
 178        writel(value, base + USBHS_UGCTRL);
 179
 180        value = readw(base + USBHS_LPSTS);
 181        value &= ~USBHS_LPSTS_SUSPM;
 182        writew(value, base + USBHS_LPSTS);
 183
 184        value = readl(base + USBHS_UGCTRL);
 185        value |= USBHS_UGCTRL_PLLRESET;
 186        writel(value, base + USBHS_UGCTRL);
 187
 188        spin_unlock_irqrestore(&drv->lock, flags);
 189
 190        return 0;
 191}
 192
 193static int rz_g1c_phy_power_on(struct phy *p)
 194{
 195        struct rcar_gen2_phy *phy = phy_get_drvdata(p);
 196        struct rcar_gen2_phy_driver *drv = phy->channel->drv;
 197        void __iomem *base = drv->base;
 198        unsigned long flags;
 199        u32 value;
 200
 201        spin_lock_irqsave(&drv->lock, flags);
 202
 203        /* Power on USBHS PHY */
 204        value = readl(base + USBHS_UGCTRL);
 205        value &= ~USBHS_UGCTRL_PLLRESET;
 206        writel(value, base + USBHS_UGCTRL);
 207
 208        /* As per the data sheet wait 340 micro sec for power stable */
 209        udelay(340);
 210
 211        if (phy->select_value == USBHS_UGCTRL2_USB0SEL_HS_USB20) {
 212                value = readw(base + USBHS_LPSTS);
 213                value |= USBHS_LPSTS_SUSPM;
 214                writew(value, base + USBHS_LPSTS);
 215        }
 216
 217        spin_unlock_irqrestore(&drv->lock, flags);
 218
 219        return 0;
 220}
 221
 222static int rz_g1c_phy_power_off(struct phy *p)
 223{
 224        struct rcar_gen2_phy *phy = phy_get_drvdata(p);
 225        struct rcar_gen2_phy_driver *drv = phy->channel->drv;
 226        void __iomem *base = drv->base;
 227        unsigned long flags;
 228        u32 value;
 229
 230        spin_lock_irqsave(&drv->lock, flags);
 231        /* Power off USBHS PHY */
 232        if (phy->select_value == USBHS_UGCTRL2_USB0SEL_HS_USB20) {
 233                value = readw(base + USBHS_LPSTS);
 234                value &= ~USBHS_LPSTS_SUSPM;
 235                writew(value, base + USBHS_LPSTS);
 236        }
 237
 238        value = readl(base + USBHS_UGCTRL);
 239        value |= USBHS_UGCTRL_PLLRESET;
 240        writel(value, base + USBHS_UGCTRL);
 241
 242        spin_unlock_irqrestore(&drv->lock, flags);
 243
 244        return 0;
 245}
 246
 247static const struct phy_ops rcar_gen2_phy_ops = {
 248        .init           = rcar_gen2_phy_init,
 249        .exit           = rcar_gen2_phy_exit,
 250        .power_on       = rcar_gen2_phy_power_on,
 251        .power_off      = rcar_gen2_phy_power_off,
 252        .owner          = THIS_MODULE,
 253};
 254
 255static const struct phy_ops rz_g1c_phy_ops = {
 256        .init           = rcar_gen2_phy_init,
 257        .exit           = rcar_gen2_phy_exit,
 258        .power_on       = rz_g1c_phy_power_on,
 259        .power_off      = rz_g1c_phy_power_off,
 260        .owner          = THIS_MODULE,
 261};
 262
 263static const u32 pci_select_value[][PHYS_PER_CHANNEL] = {
 264        [0]     = { USBHS_UGCTRL2_USB0SEL_PCI, USBHS_UGCTRL2_USB0SEL_HS_USB },
 265        [2]     = { USBHS_UGCTRL2_USB2SEL_PCI, USBHS_UGCTRL2_USB2SEL_USB30 },
 266};
 267
 268static const u32 usb20_select_value[][PHYS_PER_CHANNEL] = {
 269        { USBHS_UGCTRL2_USB0SEL_USB20, USBHS_UGCTRL2_USB0SEL_HS_USB20 },
 270};
 271
 272static const struct rcar_gen2_phy_data rcar_gen2_usb_phy_data = {
 273        .gen2_phy_ops = &rcar_gen2_phy_ops,
 274        .select_value = pci_select_value,
 275        .num_channels = ARRAY_SIZE(pci_select_value),
 276};
 277
 278static const struct rcar_gen2_phy_data rz_g1c_usb_phy_data = {
 279        .gen2_phy_ops = &rz_g1c_phy_ops,
 280        .select_value = usb20_select_value,
 281        .num_channels = ARRAY_SIZE(usb20_select_value),
 282};
 283
 284static const struct of_device_id rcar_gen2_phy_match_table[] = {
 285        {
 286                .compatible = "renesas,usb-phy-r8a77470",
 287                .data = &rz_g1c_usb_phy_data,
 288        },
 289        {
 290                .compatible = "renesas,usb-phy-r8a7790",
 291                .data = &rcar_gen2_usb_phy_data,
 292        },
 293        {
 294                .compatible = "renesas,usb-phy-r8a7791",
 295                .data = &rcar_gen2_usb_phy_data,
 296        },
 297        {
 298                .compatible = "renesas,usb-phy-r8a7794",
 299                .data = &rcar_gen2_usb_phy_data,
 300        },
 301        {
 302                .compatible = "renesas,rcar-gen2-usb-phy",
 303                .data = &rcar_gen2_usb_phy_data,
 304        },
 305        { /* sentinel */ },
 306};
 307MODULE_DEVICE_TABLE(of, rcar_gen2_phy_match_table);
 308
 309static struct phy *rcar_gen2_phy_xlate(struct device *dev,
 310                                       struct of_phandle_args *args)
 311{
 312        struct rcar_gen2_phy_driver *drv;
 313        struct device_node *np = args->np;
 314        int i;
 315
 316        drv = dev_get_drvdata(dev);
 317        if (!drv)
 318                return ERR_PTR(-EINVAL);
 319
 320        for (i = 0; i < drv->num_channels; i++) {
 321                if (np == drv->channels[i].of_node)
 322                        break;
 323        }
 324
 325        if (i >= drv->num_channels || args->args[0] >= 2)
 326                return ERR_PTR(-ENODEV);
 327
 328        return drv->channels[i].phys[args->args[0]].phy;
 329}
 330
 331static const u32 select_mask[] = {
 332        [0]     = USBHS_UGCTRL2_USB0SEL,
 333        [2]     = USBHS_UGCTRL2_USB2SEL,
 334};
 335
 336static int rcar_gen2_phy_probe(struct platform_device *pdev)
 337{
 338        struct device *dev = &pdev->dev;
 339        struct rcar_gen2_phy_driver *drv;
 340        struct phy_provider *provider;
 341        struct device_node *np;
 342        void __iomem *base;
 343        struct clk *clk;
 344        const struct rcar_gen2_phy_data *data;
 345        int i = 0;
 346
 347        if (!dev->of_node) {
 348                dev_err(dev,
 349                        "This driver is required to be instantiated from device tree\n");
 350                return -EINVAL;
 351        }
 352
 353        clk = devm_clk_get(dev, "usbhs");
 354        if (IS_ERR(clk)) {
 355                dev_err(dev, "Can't get USBHS clock\n");
 356                return PTR_ERR(clk);
 357        }
 358
 359        base = devm_platform_ioremap_resource(pdev, 0);
 360        if (IS_ERR(base))
 361                return PTR_ERR(base);
 362
 363        drv = devm_kzalloc(dev, sizeof(*drv), GFP_KERNEL);
 364        if (!drv)
 365                return -ENOMEM;
 366
 367        spin_lock_init(&drv->lock);
 368
 369        drv->clk = clk;
 370        drv->base = base;
 371
 372        data = of_device_get_match_data(dev);
 373        if (!data)
 374                return -EINVAL;
 375
 376        drv->num_channels = of_get_child_count(dev->of_node);
 377        drv->channels = devm_kcalloc(dev, drv->num_channels,
 378                                     sizeof(struct rcar_gen2_channel),
 379                                     GFP_KERNEL);
 380        if (!drv->channels)
 381                return -ENOMEM;
 382
 383        for_each_child_of_node(dev->of_node, np) {
 384                struct rcar_gen2_channel *channel = drv->channels + i;
 385                u32 channel_num;
 386                int error, n;
 387
 388                channel->of_node = np;
 389                channel->drv = drv;
 390                channel->selected_phy = -1;
 391
 392                error = of_property_read_u32(np, "reg", &channel_num);
 393                if (error || channel_num >= data->num_channels) {
 394                        dev_err(dev, "Invalid \"reg\" property\n");
 395                        of_node_put(np);
 396                        return error;
 397                }
 398                channel->select_mask = select_mask[channel_num];
 399
 400                for (n = 0; n < PHYS_PER_CHANNEL; n++) {
 401                        struct rcar_gen2_phy *phy = &channel->phys[n];
 402
 403                        phy->channel = channel;
 404                        phy->number = n;
 405                        phy->select_value = data->select_value[channel_num][n];
 406
 407                        phy->phy = devm_phy_create(dev, NULL,
 408                                                   data->gen2_phy_ops);
 409                        if (IS_ERR(phy->phy)) {
 410                                dev_err(dev, "Failed to create PHY\n");
 411                                of_node_put(np);
 412                                return PTR_ERR(phy->phy);
 413                        }
 414                        phy_set_drvdata(phy->phy, phy);
 415                }
 416
 417                i++;
 418        }
 419
 420        provider = devm_of_phy_provider_register(dev, rcar_gen2_phy_xlate);
 421        if (IS_ERR(provider)) {
 422                dev_err(dev, "Failed to register PHY provider\n");
 423                return PTR_ERR(provider);
 424        }
 425
 426        dev_set_drvdata(dev, drv);
 427
 428        return 0;
 429}
 430
 431static struct platform_driver rcar_gen2_phy_driver = {
 432        .driver = {
 433                .name           = "phy_rcar_gen2",
 434                .of_match_table = rcar_gen2_phy_match_table,
 435        },
 436        .probe  = rcar_gen2_phy_probe,
 437};
 438
 439module_platform_driver(rcar_gen2_phy_driver);
 440
 441MODULE_LICENSE("GPL v2");
 442MODULE_DESCRIPTION("Renesas R-Car Gen2 PHY");
 443MODULE_AUTHOR("Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>");
 444