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 13 struct 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 21 static 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 39 static 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 57 static 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 63 static 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 91 static const struct of_device_id ath79_usb_phy_of_match[] = { 92 { .compatible = "qca,ar7100-usb-phy" }, 93 {} 94 }; 95 MODULE_DEVICE_TABLE(of, ath79_usb_phy_of_match); 96 97 static 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 }; 104 module_platform_driver(ath79_usb_phy_driver); 105 106 MODULE_DESCRIPTION("ATH79 USB PHY driver"); 107 MODULE_AUTHOR("Alban Bedel <albeu@free.fr>"); 108 MODULE_LICENSE("GPL"); 109