// SPDX-License-Identifier: GPL-2.0+
/*
* NOP USB transceiver for all USB transceiver which are either built-in
* into USB IP or which are mostly autonomous.
*
* Copyright (C) 2009 Texas Instruments Inc
* Author: Ajay Kumar Gupta <[email protected]>
*
* Current status:
* This provides a "nop" transceiver for PHYs which are
* autonomous such as isp1504, isp1707, etc.
*/
#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/dma-mapping.h>
#include <linux/usb/gadget.h>
#include <linux/usb/otg.h>
#include <linux/usb/usb_phy_generic.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/regulator/consumer.h>
#include <linux/of.h>
#include <linux/gpio/consumer.h>
#include <linux/delay.h>
#include "phy-generic.h"
#define VBUS_IRQ_FLAGS \
(IRQF_SHARED | IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING | \
IRQF_ONESHOT)
struct platform_device *usb_phy_generic_register(void)
{
return platform_device_register_simple("usb_phy_generic",
PLATFORM_DEVID_AUTO, NULL, 0);
}
EXPORT_SYMBOL_GPL(usb_phy_generic_register);
void usb_phy_generic_unregister(struct platform_device *pdev)
{
platform_device_unregister(pdev);
}
EXPORT_SYMBOL_GPL(usb_phy_generic_unregister);
static int nop_set_suspend(struct usb_phy *x, int suspend)
{
struct usb_phy_generic *nop = dev_get_drvdata(x->dev);
int ret = 0;
if (suspend) {
if (!IS_ERR(nop->clk))
clk_disable_unprepare(nop->clk);
if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev))
ret = regulator_disable(nop->vcc);
} else {
if (!IS_ERR(nop->vcc) && !device_may_wakeup(x->dev))
ret = regulator_enable(nop->vcc);
if (!IS_ERR(nop->clk))
clk_prepare_enable(nop->clk);
}
return ret;
}
static void nop_reset(struct usb_phy_generic *nop)
{
if (!nop->gpiod_reset)
return;
gpiod_set_value_cansleep(nop->gpiod_reset, 1);
usleep_range(10000, 20000);
gpiod_set_value_cansleep(nop->gpiod_reset, 0);
usleep_range(10000, 30000);
}
/* interface to regulator framework */
static int nop_set_vbus(struct usb_otg *otg, bool enable)
{
int ret = 0;
struct usb_phy_generic *nop = dev_get_drvdata(otg->usb_phy->dev);
if (!nop->vbus_draw)
return 0;
if (enable && !nop->vbus_draw_enabled) {
ret = regulator_enable(nop->vbus_draw);
if (ret)
nop->vbus_draw_enabled = false;
else
nop->vbus_draw_enabled = true;
} else if (!enable && nop->vbus_draw_enabled) {
ret = regulator_disable(nop->vbus_draw);
nop->vbus_draw_enabled = false;
}
return ret;
}
static irqreturn_t nop_gpio_vbus_thread(int irq, void *data)
{
struct usb_phy_generic *nop = data;
struct usb_otg *otg = nop->phy.otg;
int vbus, status;
vbus = gpiod_get_value(nop->gpiod_vbus);
if ((vbus ^ nop->vbus) == 0)
return IRQ_HANDLED;
nop->vbus = vbus;
if (vbus) {
status = USB_EVENT_VBUS;
otg->state = OTG_STATE_B_PERIPHERAL;
nop->phy.last_event = status;
atomic_notifier_call_chain(&nop->phy.notifier, status,
otg->gadget);
} else {
status = USB_EVENT_NONE;
otg->state = OTG_STATE_B_IDLE;
nop->phy.last_event = status;
atomic_notifier_call_chain(&nop->phy.notifier, status,
otg->gadget);
}
return IRQ_HANDLED;
}
int usb_gen_phy_init(struct usb_phy *phy)
{
struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);
int ret;
if (!IS_ERR(nop->vcc)) {
if (regulator_enable(nop->vcc))
dev_err(phy->dev, "Failed to enable power\n");
}
if (!IS_ERR(nop->clk)) {
ret = clk_prepare_enable(nop->clk);
if (ret)
return ret;
}
nop_reset(nop);
return 0;
}
EXPORT_SYMBOL_GPL(usb_gen_phy_init);
void usb_gen_phy_shutdown(struct usb_phy *phy)
{
struct usb_phy_generic *nop = dev_get_drvdata(phy->dev);
gpiod_set_value_cansleep(nop->gpiod_reset, 1);
if (!IS_ERR(nop->clk))
clk_disable_unprepare(nop->clk);
if (!IS_ERR(nop->vcc)) {
if (regulator_disable(nop->vcc))
dev_err(phy->dev, "Failed to disable power\n");
}
}
EXPORT_SYMBOL_GPL(usb_gen_phy_shutdown);
static int nop_set_peripheral(struct usb_otg *otg, struct usb_gadget *gadget)
{
if (!otg)
return -ENODEV;
if (!gadget) {
otg->gadget = NULL;
return -ENODEV;
}
otg->gadget = gadget;
if (otg->state == OTG_STATE_B_PERIPHERAL)
atomic_notifier_call_chain(&otg->usb_phy->notifier,
USB_EVENT_VBUS, otg->gadget);
else
otg->state = OTG_STATE_B_IDLE;
return 0;
}
static int nop_set_host(struct usb_otg *otg, struct usb_bus *host)
{
if (!otg)
return -ENODEV;
if (!host) {
otg->host = NULL;
return -ENODEV;
}
otg->host = host;
return 0;
}
int usb_phy_gen_create_phy(struct device *dev, struct usb_phy_generic *nop)
{
enum usb_phy_type type = USB_PHY_TYPE_USB2;
int err = 0;
u32 clk_rate = 0;
bool needs_clk = false;
if (dev->of_node) {
struct device_node *node = dev->of_node;
if (of_property_read_u32(node, "clock-frequency", &clk_rate))
clk_rate = 0;
needs_clk = of_property_read_bool(node, "clocks");
}
nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset",
GPIOD_ASIS);
err = PTR_ERR_OR_ZERO(nop->gpiod_reset);
if (!err) {
nop->gpiod_vbus = devm_gpiod_get_optional(dev,
"vbus-detect",
GPIOD_ASIS);
err = PTR_ERR_OR_ZERO(nop->gpiod_vbus);
}
if (err)
return dev_err_probe(dev, err,
"Error requesting RESET or VBUS GPIO\n");
if (nop->gpiod_reset)
gpiod_direction_output(nop->gpiod_reset, 1);
nop->phy.otg = devm_kzalloc(dev, sizeof(*nop->phy.otg),
GFP_KERNEL);
if (!nop->phy.otg)
return -ENOMEM;
nop->clk = devm_clk_get(dev, "main_clk");
if (IS_ERR(nop->clk)) {
dev_dbg(dev, "Can't get phy clock: %ld\n",
PTR_ERR(nop->clk));
if (needs_clk)
return PTR_ERR(nop->clk);
}
if (!IS_ERR(nop->clk) && clk_rate) {
err = clk_set_rate(nop->clk, clk_rate);
if (err) {
dev_err(dev, "Error setting clock rate\n");
return err;
}
}
nop->vcc = devm_regulator_get_optional(dev, "vcc");
if (IS_ERR(nop->vcc) && PTR_ERR(nop->vcc) != -ENODEV)
return dev_err_probe(dev, PTR_ERR(nop->vcc),
"could not get vcc regulator\n");
nop->vbus_draw = devm_regulator_get_exclusive(dev, "vbus");
if (PTR_ERR(nop->vbus_draw) == -ENODEV)
nop->vbus_draw = NULL;
if (IS_ERR(nop->vbus_draw))
return dev_err_probe(dev, PTR_ERR(nop->vbus_draw),
"could not get vbus regulator\n");
nop->dev = dev;
nop->phy.dev = nop->dev;
nop->phy.label = "nop-xceiv";
nop->phy.set_suspend = nop_set_suspend;
nop->phy.type = type;
nop->phy.otg->state = OTG_STATE_UNDEFINED;
nop->phy.otg->usb_phy = &nop->phy;
nop->phy.otg->set_host = nop_set_host;
nop->phy.otg->set_peripheral = nop_set_peripheral;
nop->phy.otg->set_vbus = nop_set_vbus;
return 0;
}
EXPORT_SYMBOL_GPL(usb_phy_gen_create_phy);
static int usb_phy_generic_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *dn = dev->of_node;
struct usb_phy_generic *nop;
int err;
nop = devm_kzalloc(dev, sizeof(*nop), GFP_KERNEL);
if (!nop)
return -ENOMEM;
err = usb_phy_gen_create_phy(dev, nop);
if (err)
return err;
if (nop->gpiod_vbus) {
err = devm_request_threaded_irq(&pdev->dev,
gpiod_to_irq(nop->gpiod_vbus),
NULL, nop_gpio_vbus_thread,
VBUS_IRQ_FLAGS, "vbus_detect",
nop);
if (err) {
dev_err(&pdev->dev, "can't request irq %i, err: %d\n",
gpiod_to_irq(nop->gpiod_vbus), err);
return err;
}
nop->phy.otg->state = gpiod_get_value(nop->gpiod_vbus) ?
OTG_STATE_B_PERIPHERAL : OTG_STATE_B_IDLE;
}
nop->phy.init = usb_gen_phy_init;
nop->phy.shutdown = usb_gen_phy_shutdown;
err = usb_add_phy_dev(&nop->phy);
if (err) {
dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
err);
return err;
}
platform_set_drvdata(pdev, nop);
device_set_wakeup_capable(&pdev->dev,
of_property_read_bool(dn, "wakeup-source"));
return 0;
}
static void usb_phy_generic_remove(struct platform_device *pdev)
{
struct usb_phy_generic *nop = platform_get_drvdata(pdev);
usb_remove_phy(&nop->phy);
if (nop->vbus_draw && nop->vbus_draw_enabled)
regulator_disable(nop->vbus_draw);
}
static const struct of_device_id nop_xceiv_dt_ids[] = {
{ .compatible = "usb-nop-xceiv" },
{ }
};
MODULE_DEVICE_TABLE(of, nop_xceiv_dt_ids);
static struct platform_driver usb_phy_generic_driver = {
.probe = usb_phy_generic_probe,
.remove_new = usb_phy_generic_remove,
.driver = {
.name = "usb_phy_generic",
.of_match_table = nop_xceiv_dt_ids,
},
};
static int __init usb_phy_generic_init(void)
{
return platform_driver_register(&usb_phy_generic_driver);
}
subsys_initcall(usb_phy_generic_init);
static void __exit usb_phy_generic_exit(void)
{
platform_driver_unregister(&usb_phy_generic_driver);
}
module_exit(usb_phy_generic_exit);
MODULE_ALIAS("platform:usb_phy_generic");
MODULE_AUTHOR("Texas Instruments Inc");
MODULE_DESCRIPTION("NOP USB Transceiver driver");
MODULE_LICENSE("GPL");
Codebase Browser
linux