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path: root/drivers/usb/phy/phy-nop.c
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Diffstat (limited to 'drivers/usb/phy/phy-nop.c')
-rw-r--r--drivers/usb/phy/phy-nop.c294
1 files changed, 294 insertions, 0 deletions
diff --git a/drivers/usb/phy/phy-nop.c b/drivers/usb/phy/phy-nop.c
new file mode 100644
index 00000000000..2b10cc969bb
--- /dev/null
+++ b/drivers/usb/phy/phy-nop.c
@@ -0,0 +1,294 @@
+/*
+ * drivers/usb/otg/nop-usb-xceiv.c
+ *
+ * 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/otg.h>
+#include <linux/usb/nop-usb-xceiv.h>
+#include <linux/slab.h>
+#include <linux/clk.h>
+#include <linux/regulator/consumer.h>
+#include <linux/of.h>
+
+struct nop_usb_xceiv {
+ struct usb_phy phy;
+ struct device *dev;
+ struct clk *clk;
+ struct regulator *vcc;
+ struct regulator *reset;
+};
+
+static struct platform_device *pd;
+
+void usb_nop_xceiv_register(void)
+{
+ if (pd)
+ return;
+ pd = platform_device_register_simple("nop_usb_xceiv", -1, NULL, 0);
+ if (!pd) {
+ printk(KERN_ERR "Unable to register usb nop transceiver\n");
+ return;
+ }
+}
+EXPORT_SYMBOL(usb_nop_xceiv_register);
+
+void usb_nop_xceiv_unregister(void)
+{
+ platform_device_unregister(pd);
+ pd = NULL;
+}
+EXPORT_SYMBOL(usb_nop_xceiv_unregister);
+
+static int nop_set_suspend(struct usb_phy *x, int suspend)
+{
+ return 0;
+}
+
+static int nop_init(struct usb_phy *phy)
+{
+ struct nop_usb_xceiv *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_enable(nop->clk);
+
+ if (!IS_ERR(nop->reset)) {
+ /* De-assert RESET */
+ if (regulator_enable(nop->reset))
+ dev_err(phy->dev, "Failed to de-assert reset\n");
+ }
+
+ return 0;
+}
+
+static void nop_shutdown(struct usb_phy *phy)
+{
+ struct nop_usb_xceiv *nop = dev_get_drvdata(phy->dev);
+
+ if (!IS_ERR(nop->reset)) {
+ /* Assert RESET */
+ if (regulator_disable(nop->reset))
+ dev_err(phy->dev, "Failed to assert reset\n");
+ }
+
+ if (!IS_ERR(nop->clk))
+ clk_disable(nop->clk);
+
+ if (!IS_ERR(nop->vcc)) {
+ if (regulator_disable(nop->vcc))
+ dev_err(phy->dev, "Failed to disable power\n");
+ }
+}
+
+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->phy->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;
+}
+
+static int nop_usb_xceiv_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct nop_usb_xceiv_platform_data *pdata = pdev->dev.platform_data;
+ struct nop_usb_xceiv *nop;
+ enum usb_phy_type type = USB_PHY_TYPE_USB2;
+ int err;
+ u32 clk_rate = 0;
+ bool needs_vcc = false;
+ bool needs_reset = false;
+
+ nop = devm_kzalloc(&pdev->dev, sizeof(*nop), GFP_KERNEL);
+ if (!nop)
+ return -ENOMEM;
+
+ nop->phy.otg = devm_kzalloc(&pdev->dev, sizeof(*nop->phy.otg),
+ GFP_KERNEL);
+ if (!nop->phy.otg)
+ return -ENOMEM;
+
+ 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");
+ needs_reset = of_property_read_bool(node, "reset-supply");
+
+ } else if (pdata) {
+ type = pdata->type;
+ clk_rate = pdata->clk_rate;
+ needs_vcc = pdata->needs_vcc;
+ needs_reset = pdata->needs_reset;
+ }
+
+ nop->clk = devm_clk_get(&pdev->dev, "main_clk");
+ if (IS_ERR(nop->clk)) {
+ dev_dbg(&pdev->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(&pdev->dev, "Error setting clock rate\n");
+ return err;
+ }
+ }
+
+ if (!IS_ERR(nop->clk)) {
+ err = clk_prepare(nop->clk);
+ if (err) {
+ dev_err(&pdev->dev, "Error preparing clock\n");
+ return err;
+ }
+ }
+
+ nop->vcc = devm_regulator_get(&pdev->dev, "vcc");
+ if (IS_ERR(nop->vcc)) {
+ dev_dbg(&pdev->dev, "Error getting vcc regulator: %ld\n",
+ PTR_ERR(nop->vcc));
+ if (needs_vcc)
+ return -EPROBE_DEFER;
+ }
+
+ nop->reset = devm_regulator_get(&pdev->dev, "reset");
+ if (IS_ERR(nop->reset)) {
+ dev_dbg(&pdev->dev, "Error getting reset regulator: %ld\n",
+ PTR_ERR(nop->reset));
+ if (needs_reset)
+ return -EPROBE_DEFER;
+ }
+
+ nop->dev = &pdev->dev;
+ nop->phy.dev = nop->dev;
+ nop->phy.label = "nop-xceiv";
+ nop->phy.set_suspend = nop_set_suspend;
+ nop->phy.init = nop_init;
+ nop->phy.shutdown = nop_shutdown;
+ nop->phy.state = OTG_STATE_UNDEFINED;
+ nop->phy.type = type;
+
+ nop->phy.otg->phy = &nop->phy;
+ nop->phy.otg->set_host = nop_set_host;
+ nop->phy.otg->set_peripheral = nop_set_peripheral;
+
+ err = usb_add_phy_dev(&nop->phy);
+ if (err) {
+ dev_err(&pdev->dev, "can't register transceiver, err: %d\n",
+ err);
+ goto err_add;
+ }
+
+ platform_set_drvdata(pdev, nop);
+
+ ATOMIC_INIT_NOTIFIER_HEAD(&nop->phy.notifier);
+
+ return 0;
+
+err_add:
+ if (!IS_ERR(nop->clk))
+ clk_unprepare(nop->clk);
+ return err;
+}
+
+static int nop_usb_xceiv_remove(struct platform_device *pdev)
+{
+ struct nop_usb_xceiv *nop = platform_get_drvdata(pdev);
+
+ if (!IS_ERR(nop->clk))
+ clk_unprepare(nop->clk);
+
+ usb_remove_phy(&nop->phy);
+
+ platform_set_drvdata(pdev, NULL);
+
+ 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 nop_usb_xceiv_driver = {
+ .probe = nop_usb_xceiv_probe,
+ .remove = nop_usb_xceiv_remove,
+ .driver = {
+ .name = "nop_usb_xceiv",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(nop_xceiv_dt_ids),
+ },
+};
+
+static int __init nop_usb_xceiv_init(void)
+{
+ return platform_driver_register(&nop_usb_xceiv_driver);
+}
+subsys_initcall(nop_usb_xceiv_init);
+
+static void __exit nop_usb_xceiv_exit(void)
+{
+ platform_driver_unregister(&nop_usb_xceiv_driver);
+}
+module_exit(nop_usb_xceiv_exit);
+
+MODULE_ALIAS("platform:nop_usb_xceiv");
+MODULE_AUTHOR("Texas Instruments Inc");
+MODULE_DESCRIPTION("NOP USB Transceiver driver");
+MODULE_LICENSE("GPL");
generated by cgit v1.2.3-18-g5258 (git 2.32.0) at 2024-12-15 17:46:21 +0000