linux-stable/drivers/usb/core/phy.c
Marek Szyprowski 34c7ed72f4 usb: core: phy: add support for PHY calibration
Some PHYs (for example Exynos5 USB3.0 DRD PHY) require calibration to be
done after every USB HCD reset. Generic PHY framework has been already
extended with phy_calibrate() function in commit 36914111e6 ("drivers:
phy: add calibrate method"). This patch adds support for it to generic
PHY handling code in USB HCD core.

Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Anand Moon <linux.amoon@gmail.com>
Tested-by: Jochen Sprickerhof <jochen@sprickerhof.de>
Link: https://lore.kernel.org/r/20190829053028.32438-2-m.szyprowski@samsung.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-09-03 15:54:55 +02:00

247 lines
5.1 KiB
C

// 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);