LXR linux/drivers/phy/qualcomm/phy-ath79-usb.c

   1// SPDX-License-Identifier: GPL-2.0+
   2/*
   3 * Atheros AR71XX/9XXX USB PHY driver
   4 *
   5 * Copyright (C) 2015-2018 Alban Bedel <albeu@free.fr>
   6 */
   7
   8#include <linux/module.h>
   9#include <linux/platform_device.h>
  10#include <linux/phy/phy.h>
  11#include <linux/reset.h>
  12
  13struct ath79_usb_phy {
  14        struct reset_control *reset;
  15        /* The suspend override logic is inverted, hence the no prefix
  16         * to make the code a bit easier to understand.
  17         */
  18        struct reset_control *no_suspend_override;
  19};
  20
  21static int ath79_usb_phy_power_on(struct phy *phy)
  22{
  23        struct ath79_usb_phy *priv = phy_get_drvdata(phy);
  24        int err = 0;
  25
  26        if (priv->no_suspend_override) {
  27                err = reset_control_assert(priv->no_suspend_override);
  28                if (err)
  29                        return err;
  30        }
  31
  32        err = reset_control_deassert(priv->reset);
  33        if (err && priv->no_suspend_override)
  34                reset_control_deassert(priv->no_suspend_override);
  35
  36        return err;
  37}
  38
  39static int ath79_usb_phy_power_off(struct phy *phy)
  40{
  41        struct ath79_usb_phy *priv = phy_get_drvdata(phy);
  42        int err = 0;
  43
  44        err = reset_control_assert(priv->reset);
  45        if (err)
  46                return err;
  47
  48        if (priv->no_suspend_override) {
  49                err = reset_control_deassert(priv->no_suspend_override);
  50                if (err)
  51                        reset_control_deassert(priv->reset);
  52        }
  53
  54        return err;
  55}
  56
  57static const struct phy_ops ath79_usb_phy_ops = {
  58        .power_on       = ath79_usb_phy_power_on,
  59        .power_off      = ath79_usb_phy_power_off,
  60        .owner          = THIS_MODULE,
  61};
  62
  63static int ath79_usb_phy_probe(struct platform_device *pdev)
  64{
  65        struct ath79_usb_phy *priv;
  66        struct phy *phy;
  67
  68        priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
  69        if (!priv)
  70                return -ENOMEM;
  71
  72        priv->reset = devm_reset_control_get(&pdev->dev, "phy");
  73        if (IS_ERR(priv->reset))
  74                return PTR_ERR(priv->reset);
  75
  76        priv->no_suspend_override = devm_reset_control_get_optional(
  77                &pdev->dev, "usb-suspend-override");
  78        if (IS_ERR(priv->no_suspend_override))
  79                return PTR_ERR(priv->no_suspend_override);
  80
  81        phy = devm_phy_create(&pdev->dev, NULL, &ath79_usb_phy_ops);
  82        if (IS_ERR(phy))
  83                return PTR_ERR(phy);
  84
  85        phy_set_drvdata(phy, priv);
  86
  87        return PTR_ERR_OR_ZERO(devm_of_phy_provider_register(
  88                                &pdev->dev, of_phy_simple_xlate));
  89}
  90
  91static const struct of_device_id ath79_usb_phy_of_match[] = {
  92        { .compatible = "qca,ar7100-usb-phy" },
  93        {}
  94};
  95MODULE_DEVICE_TABLE(of, ath79_usb_phy_of_match);
  96
  97static struct platform_driver ath79_usb_phy_driver = {
  98        .probe  = ath79_usb_phy_probe,
  99        .driver = {
 100                .of_match_table = ath79_usb_phy_of_match,
 101                .name           = "ath79-usb-phy",
 102        }
 103};
 104module_platform_driver(ath79_usb_phy_driver);
 105
 106MODULE_DESCRIPTION("ATH79 USB PHY driver");
 107MODULE_AUTHOR("Alban Bedel <albeu@free.fr>");
 108MODULE_LICENSE("GPL");
 109