1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * A wrapper for multiple PHYs which passes all phy_* function calls to 4 * multiple (actual) PHY devices. This is comes handy when initializing 5 * all PHYs on a HCD and to keep them all in the same state. 6 * 7 * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@googlemail.com> 8 */ 9 10 #include <linux/device.h> 11 #include <linux/list.h> 12 #include <linux/phy/phy.h> 13 #include <linux/of.h> 14 15 #include "phy.h" 16 17 struct usb_phy_roothub { 18 struct phy *phy; 19 struct list_head list; 20 }; 21 22 static int usb_phy_roothub_add_phy(struct device *dev, int index, 23 struct list_head *list) 24 { 25 struct usb_phy_roothub *roothub_entry; 26 struct phy *phy; 27 28 phy = devm_of_phy_get_by_index(dev, dev->of_node, index); 29 if (IS_ERR(phy)) { 30 if (PTR_ERR(phy) == -ENODEV) 31 return 0; 32 else 33 return PTR_ERR(phy); 34 } 35 36 roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL); 37 if (!roothub_entry) 38 return -ENOMEM; 39 40 INIT_LIST_HEAD(&roothub_entry->list); 41 42 roothub_entry->phy = phy; 43 44 list_add_tail(&roothub_entry->list, list); 45 46 return 0; 47 } 48 49 struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev) 50 { 51 struct usb_phy_roothub *phy_roothub; 52 int i, num_phys, err; 53 54 if (!IS_ENABLED(CONFIG_GENERIC_PHY)) 55 return NULL; 56 57 num_phys = of_count_phandle_with_args(dev->of_node, "phys", 58 "#phy-cells"); 59 if (num_phys <= 0) 60 return NULL; 61 62 phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL); 63 if (!phy_roothub) 64 return ERR_PTR(-ENOMEM); 65 66 INIT_LIST_HEAD(&phy_roothub->list); 67 68 for (i = 0; i < num_phys; i++) { 69 err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list); 70 if (err) 71 return ERR_PTR(err); 72 } 73 74 return phy_roothub; 75 } 76 EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc); 77 78 int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub) 79 { 80 struct usb_phy_roothub *roothub_entry; 81 struct list_head *head; 82 int err; 83 84 if (!phy_roothub) 85 return 0; 86 87 head = &phy_roothub->list; 88 89 list_for_each_entry(roothub_entry, head, list) { 90 err = phy_init(roothub_entry->phy); 91 if (err) 92 goto err_exit_phys; 93 } 94 95 return 0; 96 97 err_exit_phys: 98 list_for_each_entry_continue_reverse(roothub_entry, head, list) 99 phy_exit(roothub_entry->phy); 100 101 return err; 102 } 103 EXPORT_SYMBOL_GPL(usb_phy_roothub_init); 104 105 int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub) 106 { 107 struct usb_phy_roothub *roothub_entry; 108 struct list_head *head; 109 int err, ret = 0; 110 111 if (!phy_roothub) 112 return 0; 113 114 head = &phy_roothub->list; 115 116 list_for_each_entry(roothub_entry, head, list) { 117 err = phy_exit(roothub_entry->phy); 118 if (err) 119 ret = err; 120 } 121 122 return ret; 123 } 124 EXPORT_SYMBOL_GPL(usb_phy_roothub_exit); 125 126 int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub) 127 { 128 struct usb_phy_roothub *roothub_entry; 129 struct list_head *head; 130 int err; 131 132 if (!phy_roothub) 133 return 0; 134 135 head = &phy_roothub->list; 136 137 list_for_each_entry(roothub_entry, head, list) { 138 err = phy_power_on(roothub_entry->phy); 139 if (err) 140 goto err_out; 141 } 142 143 return 0; 144 145 err_out: 146 list_for_each_entry_continue_reverse(roothub_entry, head, list) 147 phy_power_off(roothub_entry->phy); 148 149 return err; 150 } 151 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on); 152 153 void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub) 154 { 155 struct usb_phy_roothub *roothub_entry; 156 157 if (!phy_roothub) 158 return; 159 160 list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list) 161 phy_power_off(roothub_entry->phy); 162 } 163 EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off); 164 165 int usb_phy_roothub_suspend(struct device *controller_dev, 166 struct usb_phy_roothub *phy_roothub) 167 { 168 usb_phy_roothub_power_off(phy_roothub); 169 170 /* keep the PHYs initialized so the device can wake up the system */ 171 if (device_may_wakeup(controller_dev)) 172 return 0; 173 174 return usb_phy_roothub_exit(phy_roothub); 175 } 176 EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend); 177 178 int usb_phy_roothub_resume(struct device *controller_dev, 179 struct usb_phy_roothub *phy_roothub) 180 { 181 int err; 182 183 /* if the device can't wake up the system _exit was called */ 184 if (!device_may_wakeup(controller_dev)) { 185 err = usb_phy_roothub_init(phy_roothub); 186 if (err) 187 return err; 188 } 189 190 err = usb_phy_roothub_power_on(phy_roothub); 191 192 /* undo _init if _power_on failed */ 193 if (err && !device_may_wakeup(controller_dev)) 194 usb_phy_roothub_exit(phy_roothub); 195 196 return err; 197 } 198 EXPORT_SYMBOL_GPL(usb_phy_roothub_resume); 199