root/drivers/phy/marvell/phy-pxa-28nm-usb2.c
// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (C) 2015 Linaro, Ltd.
 * Rob Herring <robh@kernel.org>
 *
 * Based on vendor driver:
 * Copyright (C) 2013 Marvell Inc.
 * Author: Chao Xie <xiechao.mail@gmail.com>
 */

#include <linux/delay.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/io.h>
#include <linux/iopoll.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/phy/phy.h>

/* USB PXA1928 PHY mapping */
#define PHY_28NM_PLL_REG0                       0x0
#define PHY_28NM_PLL_REG1                       0x4
#define PHY_28NM_CAL_REG                        0x8
#define PHY_28NM_TX_REG0                        0x0c
#define PHY_28NM_TX_REG1                        0x10
#define PHY_28NM_RX_REG0                        0x14
#define PHY_28NM_RX_REG1                        0x18
#define PHY_28NM_DIG_REG0                       0x1c
#define PHY_28NM_DIG_REG1                       0x20
#define PHY_28NM_TEST_REG0                      0x24
#define PHY_28NM_TEST_REG1                      0x28
#define PHY_28NM_MOC_REG                        0x2c
#define PHY_28NM_PHY_RESERVE                    0x30
#define PHY_28NM_OTG_REG                        0x34
#define PHY_28NM_CHRG_DET                       0x38
#define PHY_28NM_CTRL_REG0                      0xc4
#define PHY_28NM_CTRL_REG1                      0xc8
#define PHY_28NM_CTRL_REG2                      0xd4
#define PHY_28NM_CTRL_REG3                      0xdc

/* PHY_28NM_PLL_REG0 */
#define PHY_28NM_PLL_READY                      BIT(31)

#define PHY_28NM_PLL_SELLPFR_SHIFT              28
#define PHY_28NM_PLL_SELLPFR_MASK               (0x3 << 28)

#define PHY_28NM_PLL_FBDIV_SHIFT                16
#define PHY_28NM_PLL_FBDIV_MASK                 (0x1ff << 16)

#define PHY_28NM_PLL_ICP_SHIFT                  8
#define PHY_28NM_PLL_ICP_MASK                   (0x7 << 8)

#define PHY_28NM_PLL_REFDIV_SHIFT               0
#define PHY_28NM_PLL_REFDIV_MASK                0x7f

/* PHY_28NM_PLL_REG1 */
#define PHY_28NM_PLL_PU_BY_REG                  BIT(1)

#define PHY_28NM_PLL_PU_PLL                     BIT(0)

/* PHY_28NM_CAL_REG */
#define PHY_28NM_PLL_PLLCAL_DONE                BIT(31)

#define PHY_28NM_PLL_IMPCAL_DONE                BIT(23)

#define PHY_28NM_PLL_KVCO_SHIFT                 16
#define PHY_28NM_PLL_KVCO_MASK                  (0x7 << 16)

#define PHY_28NM_PLL_CAL12_SHIFT                20
#define PHY_28NM_PLL_CAL12_MASK                 (0x3 << 20)

#define PHY_28NM_IMPCAL_VTH_SHIFT               8
#define PHY_28NM_IMPCAL_VTH_MASK                (0x7 << 8)

#define PHY_28NM_PLLCAL_START_SHIFT             22
#define PHY_28NM_IMPCAL_START_SHIFT             13

/* PHY_28NM_TX_REG0 */
#define PHY_28NM_TX_PU_BY_REG                   BIT(25)

#define PHY_28NM_TX_PU_ANA                      BIT(24)

#define PHY_28NM_TX_AMP_SHIFT                   20
#define PHY_28NM_TX_AMP_MASK                    (0x7 << 20)

/* PHY_28NM_RX_REG0 */
#define PHY_28NM_RX_SQ_THRESH_SHIFT             0
#define PHY_28NM_RX_SQ_THRESH_MASK              (0xf << 0)

/* PHY_28NM_RX_REG1 */
#define PHY_28NM_RX_SQCAL_DONE                  BIT(31)

/* PHY_28NM_DIG_REG0 */
#define PHY_28NM_DIG_BITSTAFFING_ERR            BIT(31)
#define PHY_28NM_DIG_SYNC_ERR                   BIT(30)

#define PHY_28NM_DIG_SQ_FILT_SHIFT              16
#define PHY_28NM_DIG_SQ_FILT_MASK               (0x7 << 16)

#define PHY_28NM_DIG_SQ_BLK_SHIFT               12
#define PHY_28NM_DIG_SQ_BLK_MASK                (0x7 << 12)

#define PHY_28NM_DIG_SYNC_NUM_SHIFT             0
#define PHY_28NM_DIG_SYNC_NUM_MASK              (0x3 << 0)

#define PHY_28NM_PLL_LOCK_BYPASS                BIT(7)

/* PHY_28NM_OTG_REG */
#define PHY_28NM_OTG_CONTROL_BY_PIN             BIT(5)
#define PHY_28NM_OTG_PU_OTG                     BIT(4)

#define PHY_28NM_CHGDTC_ENABLE_SWITCH_DM_SHIFT_28 13
#define PHY_28NM_CHGDTC_ENABLE_SWITCH_DP_SHIFT_28 12
#define PHY_28NM_CHGDTC_VSRC_CHARGE_SHIFT_28    10
#define PHY_28NM_CHGDTC_VDAT_CHARGE_SHIFT_28    8
#define PHY_28NM_CHGDTC_CDP_DM_AUTO_SWITCH_SHIFT_28 7
#define PHY_28NM_CHGDTC_DP_DM_SWAP_SHIFT_28     6
#define PHY_28NM_CHGDTC_PU_CHRG_DTC_SHIFT_28    5
#define PHY_28NM_CHGDTC_PD_EN_SHIFT_28          4
#define PHY_28NM_CHGDTC_DCP_EN_SHIFT_28         3
#define PHY_28NM_CHGDTC_CDP_EN_SHIFT_28         2
#define PHY_28NM_CHGDTC_TESTMON_CHRGDTC_SHIFT_28 0

#define PHY_28NM_CTRL1_CHRG_DTC_OUT_SHIFT_28    4
#define PHY_28NM_CTRL1_VBUSDTC_OUT_SHIFT_28     2

#define PHY_28NM_CTRL3_OVERWRITE                BIT(0)
#define PHY_28NM_CTRL3_VBUS_VALID               BIT(4)
#define PHY_28NM_CTRL3_AVALID                   BIT(5)
#define PHY_28NM_CTRL3_BVALID                   BIT(6)

struct mv_usb2_phy {
        struct phy              *phy;
        struct platform_device  *pdev;
        void __iomem            *base;
        struct clk              *clk;
};

static int wait_for_reg(void __iomem *reg, u32 mask, u32 ms)
{
        u32 val;

        return readl_poll_timeout(reg, val, ((val & mask) == mask),
                                   1000, 1000 * ms);
}

static int mv_usb2_phy_28nm_init(struct phy *phy)
{
        struct mv_usb2_phy *mv_phy = phy_get_drvdata(phy);
        struct platform_device *pdev = mv_phy->pdev;
        void __iomem *base = mv_phy->base;
        u32 reg;
        int ret;

        clk_prepare_enable(mv_phy->clk);

        /* PHY_28NM_PLL_REG0 */
        reg = readl(base + PHY_28NM_PLL_REG0) &
                ~(PHY_28NM_PLL_SELLPFR_MASK | PHY_28NM_PLL_FBDIV_MASK
                | PHY_28NM_PLL_ICP_MASK | PHY_28NM_PLL_REFDIV_MASK);
        writel(reg | (0x1 << PHY_28NM_PLL_SELLPFR_SHIFT
                | 0xf0 << PHY_28NM_PLL_FBDIV_SHIFT
                | 0x3 << PHY_28NM_PLL_ICP_SHIFT
                | 0xd << PHY_28NM_PLL_REFDIV_SHIFT),
                base + PHY_28NM_PLL_REG0);

        /* PHY_28NM_PLL_REG1 */
        reg = readl(base + PHY_28NM_PLL_REG1);
        writel(reg | PHY_28NM_PLL_PU_PLL | PHY_28NM_PLL_PU_BY_REG,
                base + PHY_28NM_PLL_REG1);

        /* PHY_28NM_TX_REG0 */
        reg = readl(base + PHY_28NM_TX_REG0) & ~PHY_28NM_TX_AMP_MASK;
        writel(reg | PHY_28NM_TX_PU_BY_REG | 0x3 << PHY_28NM_TX_AMP_SHIFT |
                PHY_28NM_TX_PU_ANA,
                base + PHY_28NM_TX_REG0);

        /* PHY_28NM_RX_REG0 */
        reg = readl(base + PHY_28NM_RX_REG0) & ~PHY_28NM_RX_SQ_THRESH_MASK;
        writel(reg | 0xa << PHY_28NM_RX_SQ_THRESH_SHIFT,
                base + PHY_28NM_RX_REG0);

        /* PHY_28NM_DIG_REG0 */
        reg = readl(base + PHY_28NM_DIG_REG0) &
                ~(PHY_28NM_DIG_BITSTAFFING_ERR | PHY_28NM_DIG_SYNC_ERR |
                PHY_28NM_DIG_SQ_FILT_MASK | PHY_28NM_DIG_SQ_BLK_MASK |
                PHY_28NM_DIG_SYNC_NUM_MASK);
        writel(reg | (0x1 << PHY_28NM_DIG_SYNC_NUM_SHIFT |
                PHY_28NM_PLL_LOCK_BYPASS),
                base + PHY_28NM_DIG_REG0);

        /* PHY_28NM_OTG_REG */
        reg = readl(base + PHY_28NM_OTG_REG) | PHY_28NM_OTG_PU_OTG;
        writel(reg & ~PHY_28NM_OTG_CONTROL_BY_PIN, base + PHY_28NM_OTG_REG);

        /*
         *  Calibration Timing
         *                 ____________________________
         *  CAL START   ___|
         *                         ____________________
         *  CAL_DONE    ___________|
         *                 | 400us |
         */

        /* Make sure PHY Calibration is ready */
        ret = wait_for_reg(base + PHY_28NM_CAL_REG,
                           PHY_28NM_PLL_PLLCAL_DONE | PHY_28NM_PLL_IMPCAL_DONE,
                           100);
        if (ret) {
                dev_warn(&pdev->dev, "USB PHY PLL calibrate not done after 100mS.");
                goto err_clk;
        }
        ret = wait_for_reg(base + PHY_28NM_RX_REG1,
                           PHY_28NM_RX_SQCAL_DONE, 100);
        if (ret) {
                dev_warn(&pdev->dev, "USB PHY RX SQ calibrate not done after 100mS.");
                goto err_clk;
        }
        /* Make sure PHY PLL is ready */
        ret = wait_for_reg(base + PHY_28NM_PLL_REG0, PHY_28NM_PLL_READY, 100);
        if (ret) {
                dev_warn(&pdev->dev, "PLL_READY not set after 100mS.");
                goto err_clk;
        }

        return 0;
err_clk:
        clk_disable_unprepare(mv_phy->clk);
        return ret;
}

static int mv_usb2_phy_28nm_power_on(struct phy *phy)
{
        struct mv_usb2_phy *mv_phy = phy_get_drvdata(phy);
        void __iomem *base = mv_phy->base;

        writel(readl(base + PHY_28NM_CTRL_REG3) |
                (PHY_28NM_CTRL3_OVERWRITE | PHY_28NM_CTRL3_VBUS_VALID |
                PHY_28NM_CTRL3_AVALID | PHY_28NM_CTRL3_BVALID),
                base + PHY_28NM_CTRL_REG3);

        return 0;
}

static int mv_usb2_phy_28nm_power_off(struct phy *phy)
{
        struct mv_usb2_phy *mv_phy = phy_get_drvdata(phy);
        void __iomem *base = mv_phy->base;

        writel(readl(base + PHY_28NM_CTRL_REG3) |
                ~(PHY_28NM_CTRL3_OVERWRITE | PHY_28NM_CTRL3_VBUS_VALID
                | PHY_28NM_CTRL3_AVALID | PHY_28NM_CTRL3_BVALID),
                base + PHY_28NM_CTRL_REG3);

        return 0;
}

static int mv_usb2_phy_28nm_exit(struct phy *phy)
{
        struct mv_usb2_phy *mv_phy = phy_get_drvdata(phy);
        void __iomem *base = mv_phy->base;
        unsigned int val;

        val = readw(base + PHY_28NM_PLL_REG1);
        val &= ~PHY_28NM_PLL_PU_PLL;
        writew(val, base + PHY_28NM_PLL_REG1);

        /* power down PHY Analog part */
        val = readw(base + PHY_28NM_TX_REG0);
        val &= ~PHY_28NM_TX_PU_ANA;
        writew(val, base + PHY_28NM_TX_REG0);

        /* power down PHY OTG part */
        val = readw(base + PHY_28NM_OTG_REG);
        val &= ~PHY_28NM_OTG_PU_OTG;
        writew(val, base + PHY_28NM_OTG_REG);

        clk_disable_unprepare(mv_phy->clk);
        return 0;
}

static const struct phy_ops usb_ops = {
        .init           = mv_usb2_phy_28nm_init,
        .power_on       = mv_usb2_phy_28nm_power_on,
        .power_off      = mv_usb2_phy_28nm_power_off,
        .exit           = mv_usb2_phy_28nm_exit,
        .owner          = THIS_MODULE,
};

static int mv_usb2_phy_probe(struct platform_device *pdev)
{
        struct phy_provider *phy_provider;
        struct mv_usb2_phy *mv_phy;

        mv_phy = devm_kzalloc(&pdev->dev, sizeof(*mv_phy), GFP_KERNEL);
        if (!mv_phy)
                return -ENOMEM;

        mv_phy->pdev = pdev;

        mv_phy->clk = devm_clk_get(&pdev->dev, NULL);
        if (IS_ERR(mv_phy->clk)) {
                dev_err(&pdev->dev, "failed to get clock.\n");
                return PTR_ERR(mv_phy->clk);
        }

        mv_phy->base = devm_platform_ioremap_resource(pdev, 0);
        if (IS_ERR(mv_phy->base))
                return PTR_ERR(mv_phy->base);

        mv_phy->phy = devm_phy_create(&pdev->dev, pdev->dev.of_node, &usb_ops);
        if (IS_ERR(mv_phy->phy))
                return PTR_ERR(mv_phy->phy);

        phy_set_drvdata(mv_phy->phy, mv_phy);

        phy_provider = devm_of_phy_provider_register(&pdev->dev, of_phy_simple_xlate);
        return PTR_ERR_OR_ZERO(phy_provider);
}

static const struct of_device_id mv_usbphy_dt_match[] = {
        { .compatible = "marvell,pxa1928-usb-phy", },
        {},
};
MODULE_DEVICE_TABLE(of, mv_usbphy_dt_match);

static struct platform_driver mv_usb2_phy_driver = {
        .probe  = mv_usb2_phy_probe,
        .driver = {
                .name   = "mv-usb2-phy",
                .of_match_table = mv_usbphy_dt_match,
        },
};
module_platform_driver(mv_usb2_phy_driver);

MODULE_AUTHOR("Rob Herring <robh@kernel.org>");
MODULE_DESCRIPTION("Marvell USB2 phy driver");
MODULE_LICENSE("GPL v2");