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