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-rw-r--r--drivers/usb/core/phy.c247
1 files changed, 247 insertions, 0 deletions
diff --git a/drivers/usb/core/phy.c b/drivers/usb/core/phy.c
new file mode 100644
index 000000000..fb1588e7c
--- /dev/null
+++ b/drivers/usb/core/phy.c
@@ -0,0 +1,247 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * A wrapper for multiple PHYs which passes all phy_* function calls to
+ * multiple (actual) PHY devices. This is comes handy when initializing
+ * all PHYs on a HCD and to keep them all in the same state.
+ *
+ * Copyright (C) 2018 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
+ */
+
+#include <linux/device.h>
+#include <linux/list.h>
+#include <linux/phy/phy.h>
+#include <linux/of.h>
+
+#include "phy.h"
+
+struct usb_phy_roothub {
+ struct phy *phy;
+ struct list_head list;
+};
+
+static int usb_phy_roothub_add_phy(struct device *dev, int index,
+ struct list_head *list)
+{
+ struct usb_phy_roothub *roothub_entry;
+ struct phy *phy;
+
+ phy = devm_of_phy_get_by_index(dev, dev->of_node, index);
+ if (IS_ERR(phy)) {
+ if (PTR_ERR(phy) == -ENODEV)
+ return 0;
+ else
+ return PTR_ERR(phy);
+ }
+
+ roothub_entry = devm_kzalloc(dev, sizeof(*roothub_entry), GFP_KERNEL);
+ if (!roothub_entry)
+ return -ENOMEM;
+
+ INIT_LIST_HEAD(&roothub_entry->list);
+
+ roothub_entry->phy = phy;
+
+ list_add_tail(&roothub_entry->list, list);
+
+ return 0;
+}
+
+struct usb_phy_roothub *usb_phy_roothub_alloc(struct device *dev)
+{
+ struct usb_phy_roothub *phy_roothub;
+ int i, num_phys, err;
+
+ if (!IS_ENABLED(CONFIG_GENERIC_PHY))
+ return NULL;
+
+ num_phys = of_count_phandle_with_args(dev->of_node, "phys",
+ "#phy-cells");
+ if (num_phys <= 0)
+ return NULL;
+
+ phy_roothub = devm_kzalloc(dev, sizeof(*phy_roothub), GFP_KERNEL);
+ if (!phy_roothub)
+ return ERR_PTR(-ENOMEM);
+
+ INIT_LIST_HEAD(&phy_roothub->list);
+
+ for (i = 0; i < num_phys; i++) {
+ err = usb_phy_roothub_add_phy(dev, i, &phy_roothub->list);
+ if (err)
+ return ERR_PTR(err);
+ }
+
+ return phy_roothub;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_alloc);
+
+int usb_phy_roothub_init(struct usb_phy_roothub *phy_roothub)
+{
+ struct usb_phy_roothub *roothub_entry;
+ struct list_head *head;
+ int err;
+
+ if (!phy_roothub)
+ return 0;
+
+ head = &phy_roothub->list;
+
+ list_for_each_entry(roothub_entry, head, list) {
+ err = phy_init(roothub_entry->phy);
+ if (err)
+ goto err_exit_phys;
+ }
+
+ return 0;
+
+err_exit_phys:
+ list_for_each_entry_continue_reverse(roothub_entry, head, list)
+ phy_exit(roothub_entry->phy);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_init);
+
+int usb_phy_roothub_exit(struct usb_phy_roothub *phy_roothub)
+{
+ struct usb_phy_roothub *roothub_entry;
+ struct list_head *head;
+ int err, ret = 0;
+
+ if (!phy_roothub)
+ return 0;
+
+ head = &phy_roothub->list;
+
+ list_for_each_entry(roothub_entry, head, list) {
+ err = phy_exit(roothub_entry->phy);
+ if (err)
+ ret = err;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_exit);
+
+int usb_phy_roothub_set_mode(struct usb_phy_roothub *phy_roothub,
+ enum phy_mode mode)
+{
+ struct usb_phy_roothub *roothub_entry;
+ struct list_head *head;
+ int err;
+
+ if (!phy_roothub)
+ return 0;
+
+ head = &phy_roothub->list;
+
+ list_for_each_entry(roothub_entry, head, list) {
+ err = phy_set_mode(roothub_entry->phy, mode);
+ if (err)
+ goto err_out;
+ }
+
+ return 0;
+
+err_out:
+ list_for_each_entry_continue_reverse(roothub_entry, head, list)
+ phy_power_off(roothub_entry->phy);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_set_mode);
+
+int usb_phy_roothub_calibrate(struct usb_phy_roothub *phy_roothub)
+{
+ struct usb_phy_roothub *roothub_entry;
+ struct list_head *head;
+ int err;
+
+ if (!phy_roothub)
+ return 0;
+
+ head = &phy_roothub->list;
+
+ list_for_each_entry(roothub_entry, head, list) {
+ err = phy_calibrate(roothub_entry->phy);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_calibrate);
+
+int usb_phy_roothub_power_on(struct usb_phy_roothub *phy_roothub)
+{
+ struct usb_phy_roothub *roothub_entry;
+ struct list_head *head;
+ int err;
+
+ if (!phy_roothub)
+ return 0;
+
+ head = &phy_roothub->list;
+
+ list_for_each_entry(roothub_entry, head, list) {
+ err = phy_power_on(roothub_entry->phy);
+ if (err)
+ goto err_out;
+ }
+
+ return 0;
+
+err_out:
+ list_for_each_entry_continue_reverse(roothub_entry, head, list)
+ phy_power_off(roothub_entry->phy);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_power_on);
+
+void usb_phy_roothub_power_off(struct usb_phy_roothub *phy_roothub)
+{
+ struct usb_phy_roothub *roothub_entry;
+
+ if (!phy_roothub)
+ return;
+
+ list_for_each_entry_reverse(roothub_entry, &phy_roothub->list, list)
+ phy_power_off(roothub_entry->phy);
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_power_off);
+
+int usb_phy_roothub_suspend(struct device *controller_dev,
+ struct usb_phy_roothub *phy_roothub)
+{
+ usb_phy_roothub_power_off(phy_roothub);
+
+ /* keep the PHYs initialized so the device can wake up the system */
+ if (device_may_wakeup(controller_dev))
+ return 0;
+
+ return usb_phy_roothub_exit(phy_roothub);
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_suspend);
+
+int usb_phy_roothub_resume(struct device *controller_dev,
+ struct usb_phy_roothub *phy_roothub)
+{
+ int err;
+
+ /* if the device can't wake up the system _exit was called */
+ if (!device_may_wakeup(controller_dev)) {
+ err = usb_phy_roothub_init(phy_roothub);
+ if (err)
+ return err;
+ }
+
+ err = usb_phy_roothub_power_on(phy_roothub);
+
+ /* undo _init if _power_on failed */
+ if (err && !device_may_wakeup(controller_dev))
+ usb_phy_roothub_exit(phy_roothub);
+
+ return err;
+}
+EXPORT_SYMBOL_GPL(usb_phy_roothub_resume);