--- /dev/null
+/*
+ * 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 <ajay.gupta@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * 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/of_gpio.h>
+#include <linux/gpio.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)
+{
+ return 0;
+}
+
+static void nop_reset(struct usb_phy_generic *nop)
+{
+ if (!nop->gpiod_reset)
+ return;
+
+ gpiod_set_value(nop->gpiod_reset, 1);
+ usleep_range(10000, 20000);
+ gpiod_set_value(nop->gpiod_reset, 0);
+}
+
+/* interface to regulator framework */
+static void nop_set_vbus_draw(struct usb_phy_generic *nop, unsigned mA)
+{
+ struct regulator *vbus_draw = nop->vbus_draw;
+ int enabled;
+ int ret;
+
+ if (!vbus_draw)
+ return;
+
+ enabled = nop->vbus_draw_enabled;
+ if (mA) {
+ regulator_set_current_limit(vbus_draw, 0, 1000 * mA);
+ if (!enabled) {
+ ret = regulator_enable(vbus_draw);
+ if (ret < 0)
+ return;
+ nop->vbus_draw_enabled = 1;
+ }
+ } else {
+ if (enabled) {
+ ret = regulator_disable(vbus_draw);
+ if (ret < 0)
+ return;
+ nop->vbus_draw_enabled = 0;
+ }
+ }
+ nop->mA = mA;
+}
+
+
+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;
+ usb_gadget_vbus_connect(otg->gadget);
+
+ /* drawing a "unit load" is *always* OK, except for OTG */
+ nop_set_vbus_draw(nop, 100);
+
+ atomic_notifier_call_chain(&nop->phy.notifier, status,
+ otg->gadget);
+ } else {
+ nop_set_vbus_draw(nop, 0);
+
+ usb_gadget_vbus_disconnect(otg->gadget);
+ 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);
+
+ if (!IS_ERR(nop->vcc)) {
+ if (regulator_enable(nop->vcc))
+ dev_err(phy->dev, "Failed to enable power\n");
+ }
+
+ if (!IS_ERR(nop->clk))
+ clk_prepare_enable(nop->clk);
+
+ 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(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;
+ 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,
+ struct usb_phy_generic_platform_data *pdata)
+{
+ enum usb_phy_type type = USB_PHY_TYPE_USB2;
+ int err = 0;
+
+ u32 clk_rate = 0;
+ bool needs_vcc = 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_vcc = of_property_read_bool(node, "vcc-supply");
+ nop->gpiod_reset = devm_gpiod_get_optional(dev, "reset");
+ err = PTR_ERR_OR_ZERO(nop->gpiod_reset);
+ if (!err) {
+ nop->gpiod_vbus = devm_gpiod_get_optional(dev,
+ "vbus-detect");
+ err = PTR_ERR_OR_ZERO(nop->gpiod_vbus);
+ }
+ } else if (pdata) {
+ type = pdata->type;
+ clk_rate = pdata->clk_rate;
+ needs_vcc = pdata->needs_vcc;
+ if (gpio_is_valid(pdata->gpio_reset)) {
+ err = devm_gpio_request_one(dev, pdata->gpio_reset, 0,
+ dev_name(dev));
+ if (!err)
+ nop->gpiod_reset =
+ gpio_to_desc(pdata->gpio_reset);
+ }
+ nop->gpiod_vbus = pdata->gpiod_vbus;
+ }
+
+ if (err == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+ if (err) {
+ dev_err(dev, "Error requesting RESET or VBUS GPIO\n");
+ return err;
+ }
+ 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 (!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(dev, "vcc");
+ if (IS_ERR(nop->vcc)) {
+ dev_dbg(dev, "Error getting vcc regulator: %ld\n",
+ PTR_ERR(nop->vcc));
+ if (needs_vcc)
+ return -EPROBE_DEFER;
+ }
+
+ 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;
+
+ 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 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, dev_get_platdata(&pdev->dev));
+ 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.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);
+
+ return 0;
+}
+
+static int usb_phy_generic_remove(struct platform_device *pdev)
+{
+ struct usb_phy_generic *nop = platform_get_drvdata(pdev);
+
+ usb_remove_phy(&nop->phy);
+
+ return 0;
+}
+
+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 = 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");
Code Review / kvmfornfv.git / blobdiff