drivers/phy/qualcomm/phy-qcom-usb-hsic.c

   1 /**
   2  * Copyright (C) 2016 Linaro Ltd
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8 #include <linux/module.h>
   9 #include <linux/ulpi/driver.h>
  10 #include <linux/ulpi/regs.h>
  11 #include <linux/phy/phy.h>
  12 #include <linux/pinctrl/consumer.h>
  13 #include <linux/pinctrl/pinctrl-state.h>
  14 #include <linux/delay.h>
  15 #include <linux/clk.h>
  16
  17 #define ULPI_HSIC_CFG           0x30
  18 #define ULPI_HSIC_IO_CAL        0x33
  19
  20 struct qcom_usb_hsic_phy {
  21         struct ulpi *ulpi;
  22         struct phy *phy;
  23         struct pinctrl *pctl;
  24         struct clk *phy_clk;
  25         struct clk *cal_clk;
  26         struct clk *cal_sleep_clk;
  27 };
  28
  29 static int qcom_usb_hsic_phy_power_on(struct phy *phy)
  30 {
  31         struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
  32         struct ulpi *ulpi = uphy->ulpi;
  33         struct pinctrl_state *pins_default;
  34         int ret;
  35
  36         ret = clk_prepare_enable(uphy->phy_clk);
  37         if (ret)
  38                 return ret;
  39
  40         ret = clk_prepare_enable(uphy->cal_clk);
  41         if (ret)
  42                 goto err_cal;
  43
  44         ret = clk_prepare_enable(uphy->cal_sleep_clk);
  45         if (ret)
  46                 goto err_sleep;
  47
  48         /* Set periodic calibration interval to ~2.048sec in HSIC_IO_CAL_REG */
  49         ret = ulpi_write(ulpi, ULPI_HSIC_IO_CAL, 0xff);
  50         if (ret)
  51                 goto err_ulpi;
  52
  53         /* Enable periodic IO calibration in HSIC_CFG register */
  54         ret = ulpi_write(ulpi, ULPI_HSIC_CFG, 0xa8);
  55         if (ret)
  56                 goto err_ulpi;
  57
  58         /* Configure pins for HSIC functionality */
  59         pins_default = pinctrl_lookup_state(uphy->pctl, PINCTRL_STATE_DEFAULT);
  60         if (IS_ERR(pins_default)) {
  61                 ret = PTR_ERR(pins_default);
  62                 goto err_ulpi;
  63         }
  64
  65         ret = pinctrl_select_state(uphy->pctl, pins_default);
  66         if (ret)
  67                 goto err_ulpi;
  68
  69          /* Enable HSIC mode in HSIC_CFG register */
  70         ret = ulpi_write(ulpi, ULPI_SET(ULPI_HSIC_CFG), 0x01);
  71         if (ret)
  72                 goto err_ulpi;
  73
  74         /* Disable auto-resume */
  75         ret = ulpi_write(ulpi, ULPI_CLR(ULPI_IFC_CTRL),
  76                          ULPI_IFC_CTRL_AUTORESUME);
  77         if (ret)
  78                 goto err_ulpi;
  79
  80         return ret;
  81 err_ulpi:
  82         clk_disable_unprepare(uphy->cal_sleep_clk);
  83 err_sleep:
  84         clk_disable_unprepare(uphy->cal_clk);
  85 err_cal:
  86         clk_disable_unprepare(uphy->phy_clk);
  87         return ret;
  88 }
  89
  90 static int qcom_usb_hsic_phy_power_off(struct phy *phy)
  91 {
  92         struct qcom_usb_hsic_phy *uphy = phy_get_drvdata(phy);
  93
  94         clk_disable_unprepare(uphy->cal_sleep_clk);
  95         clk_disable_unprepare(uphy->cal_clk);
  96         clk_disable_unprepare(uphy->phy_clk);
  97
  98         return 0;
  99 }
 100
 101 static const struct phy_ops qcom_usb_hsic_phy_ops = {
 102         .power_on = qcom_usb_hsic_phy_power_on,
 103         .power_off = qcom_usb_hsic_phy_power_off,
 104         .owner = THIS_MODULE,
 105 };
 106
 107 static int qcom_usb_hsic_phy_probe(struct ulpi *ulpi)
 108 {
 109         struct qcom_usb_hsic_phy *uphy;
 110         struct phy_provider *p;
 111         struct clk *clk;
 112
 113         uphy = devm_kzalloc(&ulpi->dev, sizeof(*uphy), GFP_KERNEL);
 114         if (!uphy)
 115                 return -ENOMEM;
 116         ulpi_set_drvdata(ulpi, uphy);
 117
 118         uphy->ulpi = ulpi;
 119         uphy->pctl = devm_pinctrl_get(&ulpi->dev);
 120         if (IS_ERR(uphy->pctl))
 121                 return PTR_ERR(uphy->pctl);
 122
 123         uphy->phy_clk = clk = devm_clk_get(&ulpi->dev, "phy");
 124         if (IS_ERR(clk))
 125                 return PTR_ERR(clk);
 126
 127         uphy->cal_clk = clk = devm_clk_get(&ulpi->dev, "cal");
 128         if (IS_ERR(clk))
 129                 return PTR_ERR(clk);
 130
 131         uphy->cal_sleep_clk = clk = devm_clk_get(&ulpi->dev, "cal_sleep");
 132         if (IS_ERR(clk))
 133                 return PTR_ERR(clk);
 134
 135         uphy->phy = devm_phy_create(&ulpi->dev, ulpi->dev.of_node,
 136                                     &qcom_usb_hsic_phy_ops);
 137         if (IS_ERR(uphy->phy))
 138                 return PTR_ERR(uphy->phy);
 139         phy_set_drvdata(uphy->phy, uphy);
 140
 141         p = devm_of_phy_provider_register(&ulpi->dev, of_phy_simple_xlate);
 142         return PTR_ERR_OR_ZERO(p);
 143 }
 144
 145 static const struct of_device_id qcom_usb_hsic_phy_match[] = {
 146         { .compatible = "qcom,usb-hsic-phy", },
 147         { }
 148 };
 149 MODULE_DEVICE_TABLE(of, qcom_usb_hsic_phy_match);
 150
 151 static struct ulpi_driver qcom_usb_hsic_phy_driver = {
 152         .probe = qcom_usb_hsic_phy_probe,
 153         .driver = {
 154                 .name = "qcom_usb_hsic_phy",
 155                 .of_match_table = qcom_usb_hsic_phy_match,
 156         },
 157 };
 158 module_ulpi_driver(qcom_usb_hsic_phy_driver);
 159
 160 MODULE_DESCRIPTION("Qualcomm USB HSIC phy");
 161 MODULE_LICENSE("GPL v2");