1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * snps_udc_plat.c - Synopsys UDC Platform Driver
4  *
5  * Copyright (C) 2016 Broadcom
6  */
7 
8 #include <linux/extcon.h>
9 #include <linux/of_address.h>
10 #include <linux/of_irq.h>
11 #include <linux/of_gpio.h>
12 #include <linux/platform_device.h>
13 #include <linux/phy/phy.h>
14 #include <linux/module.h>
15 #include <linux/dmapool.h>
16 #include <linux/interrupt.h>
17 #include <linux/moduleparam.h>
18 #include "amd5536udc.h"
19 
20 /* description */
21 #define UDC_MOD_DESCRIPTION     "Synopsys UDC platform driver"
22 
23 static void start_udc(struct udc *udc)
24 {
25 	if (udc->driver) {
26 		dev_info(udc->dev, "Connecting...\n");
27 		udc_enable_dev_setup_interrupts(udc);
28 		udc_basic_init(udc);
29 		udc->connected = 1;
30 	}
31 }
32 
33 static void stop_udc(struct udc *udc)
34 {
35 	int tmp;
36 	u32 reg;
37 
38 	spin_lock(&udc->lock);
39 
40 	/* Flush the receieve fifo */
41 	reg = readl(&udc->regs->ctl);
42 	reg |= AMD_BIT(UDC_DEVCTL_SRX_FLUSH);
43 	writel(reg, &udc->regs->ctl);
44 
45 	reg = readl(&udc->regs->ctl);
46 	reg &= ~(AMD_BIT(UDC_DEVCTL_SRX_FLUSH));
47 	writel(reg, &udc->regs->ctl);
48 	dev_dbg(udc->dev, "ep rx queue flushed\n");
49 
50 	/* Mask interrupts. Required more so when the
51 	 * UDC is connected to a DRD phy.
52 	 */
53 	udc_mask_unused_interrupts(udc);
54 
55 	/* Disconnect gadget driver */
56 	if (udc->driver) {
57 		spin_unlock(&udc->lock);
58 		udc->driver->disconnect(&udc->gadget);
59 		spin_lock(&udc->lock);
60 
61 		/* empty queues */
62 		for (tmp = 0; tmp < UDC_EP_NUM; tmp++)
63 			empty_req_queue(&udc->ep[tmp]);
64 	}
65 	udc->connected = 0;
66 
67 	spin_unlock(&udc->lock);
68 	dev_info(udc->dev, "Device disconnected\n");
69 }
70 
71 static void udc_drd_work(struct work_struct *work)
72 {
73 	struct udc *udc;
74 
75 	udc = container_of(to_delayed_work(work),
76 			   struct udc, drd_work);
77 
78 	if (udc->conn_type) {
79 		dev_dbg(udc->dev, "idle -> device\n");
80 		start_udc(udc);
81 	} else {
82 		dev_dbg(udc->dev, "device -> idle\n");
83 		stop_udc(udc);
84 	}
85 }
86 
87 static int usbd_connect_notify(struct notifier_block *self,
88 			       unsigned long event, void *ptr)
89 {
90 	struct udc *udc = container_of(self, struct udc, nb);
91 
92 	dev_dbg(udc->dev, "%s: event: %lu\n", __func__, event);
93 
94 	udc->conn_type = event;
95 
96 	schedule_delayed_work(&udc->drd_work, 0);
97 
98 	return NOTIFY_OK;
99 }
100 
101 static int udc_plat_probe(struct platform_device *pdev)
102 {
103 	struct device *dev = &pdev->dev;
104 	struct resource *res;
105 	struct udc *udc;
106 	int ret;
107 
108 	udc = devm_kzalloc(dev, sizeof(*udc), GFP_KERNEL);
109 	if (!udc)
110 		return -ENOMEM;
111 
112 	spin_lock_init(&udc->lock);
113 	udc->dev = dev;
114 
115 	udc->virt_addr = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
116 	if (IS_ERR(udc->virt_addr))
117 		return PTR_ERR(udc->virt_addr);
118 
119 	/* udc csr registers base */
120 	udc->csr = udc->virt_addr + UDC_CSR_ADDR;
121 
122 	/* dev registers base */
123 	udc->regs = udc->virt_addr + UDC_DEVCFG_ADDR;
124 
125 	/* ep registers base */
126 	udc->ep_regs = udc->virt_addr + UDC_EPREGS_ADDR;
127 
128 	/* fifo's base */
129 	udc->rxfifo = (u32 __iomem *)(udc->virt_addr + UDC_RXFIFO_ADDR);
130 	udc->txfifo = (u32 __iomem *)(udc->virt_addr + UDC_TXFIFO_ADDR);
131 
132 	udc->phys_addr = (unsigned long)res->start;
133 
134 	udc->irq = irq_of_parse_and_map(dev->of_node, 0);
135 	if (udc->irq <= 0) {
136 		dev_err(dev, "Can't parse and map interrupt\n");
137 		return -EINVAL;
138 	}
139 
140 	udc->udc_phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);
141 	if (IS_ERR(udc->udc_phy)) {
142 		dev_err(dev, "Failed to obtain phy from device tree\n");
143 		return PTR_ERR(udc->udc_phy);
144 	}
145 
146 	ret = phy_init(udc->udc_phy);
147 	if (ret) {
148 		dev_err(dev, "UDC phy init failed");
149 		return ret;
150 	}
151 
152 	ret = phy_power_on(udc->udc_phy);
153 	if (ret) {
154 		dev_err(dev, "UDC phy power on failed");
155 		phy_exit(udc->udc_phy);
156 		return ret;
157 	}
158 
159 	/* Register for extcon if supported */
160 	if (of_property_present(dev->of_node, "extcon")) {
161 		udc->edev = extcon_get_edev_by_phandle(dev, 0);
162 		if (IS_ERR(udc->edev)) {
163 			if (PTR_ERR(udc->edev) == -EPROBE_DEFER)
164 				return -EPROBE_DEFER;
165 			dev_err(dev, "Invalid or missing extcon\n");
166 			ret = PTR_ERR(udc->edev);
167 			goto exit_phy;
168 		}
169 
170 		udc->nb.notifier_call = usbd_connect_notify;
171 		ret = extcon_register_notifier(udc->edev, EXTCON_USB,
172 					       &udc->nb);
173 		if (ret < 0) {
174 			dev_err(dev, "Can't register extcon device\n");
175 			goto exit_phy;
176 		}
177 
178 		ret = extcon_get_state(udc->edev, EXTCON_USB);
179 		if (ret < 0) {
180 			dev_err(dev, "Can't get cable state\n");
181 			goto exit_extcon;
182 		} else if (ret) {
183 			udc->conn_type = ret;
184 		}
185 		INIT_DELAYED_WORK(&udc->drd_work, udc_drd_work);
186 	}
187 
188 	/* init dma pools */
189 	if (use_dma) {
190 		ret = init_dma_pools(udc);
191 		if (ret != 0)
192 			goto exit_extcon;
193 	}
194 
195 	ret = devm_request_irq(dev, udc->irq, udc_irq, IRQF_SHARED,
196 			       "snps-udc", udc);
197 	if (ret < 0) {
198 		dev_err(dev, "Request irq %d failed for UDC\n", udc->irq);
199 		goto exit_dma;
200 	}
201 
202 	platform_set_drvdata(pdev, udc);
203 	udc->chiprev = UDC_BCM_REV;
204 
205 	if (udc_probe(udc)) {
206 		ret = -ENODEV;
207 		goto exit_dma;
208 	}
209 	dev_info(dev, "Synopsys UDC platform driver probe successful\n");
210 
211 	return 0;
212 
213 exit_dma:
214 	if (use_dma)
215 		free_dma_pools(udc);
216 exit_extcon:
217 	if (udc->edev)
218 		extcon_unregister_notifier(udc->edev, EXTCON_USB, &udc->nb);
219 exit_phy:
220 	if (udc->udc_phy) {
221 		phy_power_off(udc->udc_phy);
222 		phy_exit(udc->udc_phy);
223 	}
224 	return ret;
225 }
226 
227 static void udc_plat_remove(struct platform_device *pdev)
228 {
229 	struct udc *dev;
230 
231 	dev = platform_get_drvdata(pdev);
232 
233 	usb_del_gadget_udc(&dev->gadget);
234 	/* gadget driver must not be registered */
235 	if (WARN_ON(dev->driver))
236 		return;
237 
238 	/* dma pool cleanup */
239 	free_dma_pools(dev);
240 
241 	udc_remove(dev);
242 
243 	platform_set_drvdata(pdev, NULL);
244 
245 	phy_power_off(dev->udc_phy);
246 	phy_exit(dev->udc_phy);
247 	extcon_unregister_notifier(dev->edev, EXTCON_USB, &dev->nb);
248 
249 	dev_info(&pdev->dev, "Synopsys UDC platform driver removed\n");
250 }
251 
252 #ifdef CONFIG_PM_SLEEP
253 static int udc_plat_suspend(struct device *dev)
254 {
255 	struct udc *udc;
256 
257 	udc = dev_get_drvdata(dev);
258 	stop_udc(udc);
259 
260 	if (extcon_get_state(udc->edev, EXTCON_USB) > 0) {
261 		dev_dbg(udc->dev, "device -> idle\n");
262 		stop_udc(udc);
263 	}
264 	phy_power_off(udc->udc_phy);
265 	phy_exit(udc->udc_phy);
266 
267 	return 0;
268 }
269 
270 static int udc_plat_resume(struct device *dev)
271 {
272 	struct udc *udc;
273 	int ret;
274 
275 	udc = dev_get_drvdata(dev);
276 
277 	ret = phy_init(udc->udc_phy);
278 	if (ret) {
279 		dev_err(udc->dev, "UDC phy init failure");
280 		return ret;
281 	}
282 
283 	ret = phy_power_on(udc->udc_phy);
284 	if (ret) {
285 		dev_err(udc->dev, "UDC phy power on failure");
286 		phy_exit(udc->udc_phy);
287 		return ret;
288 	}
289 
290 	if (extcon_get_state(udc->edev, EXTCON_USB) > 0) {
291 		dev_dbg(udc->dev, "idle -> device\n");
292 		start_udc(udc);
293 	}
294 
295 	return 0;
296 }
297 static const struct dev_pm_ops udc_plat_pm_ops = {
298 	.suspend	= udc_plat_suspend,
299 	.resume		= udc_plat_resume,
300 };
301 #endif
302 
303 static const struct of_device_id of_udc_match[] = {
304 	{ .compatible = "brcm,ns2-udc", },
305 	{ .compatible = "brcm,cygnus-udc", },
306 	{ .compatible = "brcm,iproc-udc", },
307 	{ }
308 };
309 MODULE_DEVICE_TABLE(of, of_udc_match);
310 
311 static struct platform_driver udc_plat_driver = {
312 	.probe		= udc_plat_probe,
313 	.remove_new	= udc_plat_remove,
314 	.driver		= {
315 		.name	= "snps-udc-plat",
316 		.of_match_table = of_udc_match,
317 #ifdef CONFIG_PM_SLEEP
318 		.pm	= &udc_plat_pm_ops,
319 #endif
320 	},
321 };
322 module_platform_driver(udc_plat_driver);
323 
324 MODULE_DESCRIPTION(UDC_MOD_DESCRIPTION);
325 MODULE_AUTHOR("Broadcom");
326 MODULE_LICENSE("GPL v2");
327