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 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
116 	udc->virt_addr = devm_ioremap_resource(dev, res);
117 	if (IS_ERR(udc->virt_addr))
118 		return PTR_ERR(udc->virt_addr);
119 
120 	/* udc csr registers base */
121 	udc->csr = udc->virt_addr + UDC_CSR_ADDR;
122 
123 	/* dev registers base */
124 	udc->regs = udc->virt_addr + UDC_DEVCFG_ADDR;
125 
126 	/* ep registers base */
127 	udc->ep_regs = udc->virt_addr + UDC_EPREGS_ADDR;
128 
129 	/* fifo's base */
130 	udc->rxfifo = (u32 __iomem *)(udc->virt_addr + UDC_RXFIFO_ADDR);
131 	udc->txfifo = (u32 __iomem *)(udc->virt_addr + UDC_TXFIFO_ADDR);
132 
133 	udc->phys_addr = (unsigned long)res->start;
134 
135 	udc->irq = irq_of_parse_and_map(dev->of_node, 0);
136 	if (udc->irq <= 0) {
137 		dev_err(dev, "Can't parse and map interrupt\n");
138 		return -EINVAL;
139 	}
140 
141 	udc->udc_phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);
142 	if (IS_ERR(udc->udc_phy)) {
143 		dev_err(dev, "Failed to obtain phy from device tree\n");
144 		return PTR_ERR(udc->udc_phy);
145 	}
146 
147 	ret = phy_init(udc->udc_phy);
148 	if (ret) {
149 		dev_err(dev, "UDC phy init failed");
150 		return ret;
151 	}
152 
153 	ret = phy_power_on(udc->udc_phy);
154 	if (ret) {
155 		dev_err(dev, "UDC phy power on failed");
156 		phy_exit(udc->udc_phy);
157 		return ret;
158 	}
159 
160 	/* Register for extcon if supported */
161 	if (of_property_present(dev->of_node, "extcon")) {
162 		udc->edev = extcon_get_edev_by_phandle(dev, 0);
163 		if (IS_ERR(udc->edev)) {
164 			if (PTR_ERR(udc->edev) == -EPROBE_DEFER)
165 				return -EPROBE_DEFER;
166 			dev_err(dev, "Invalid or missing extcon\n");
167 			ret = PTR_ERR(udc->edev);
168 			goto exit_phy;
169 		}
170 
171 		udc->nb.notifier_call = usbd_connect_notify;
172 		ret = extcon_register_notifier(udc->edev, EXTCON_USB,
173 					       &udc->nb);
174 		if (ret < 0) {
175 			dev_err(dev, "Can't register extcon device\n");
176 			goto exit_phy;
177 		}
178 
179 		ret = extcon_get_state(udc->edev, EXTCON_USB);
180 		if (ret < 0) {
181 			dev_err(dev, "Can't get cable state\n");
182 			goto exit_extcon;
183 		} else if (ret) {
184 			udc->conn_type = ret;
185 		}
186 		INIT_DELAYED_WORK(&udc->drd_work, udc_drd_work);
187 	}
188 
189 	/* init dma pools */
190 	if (use_dma) {
191 		ret = init_dma_pools(udc);
192 		if (ret != 0)
193 			goto exit_extcon;
194 	}
195 
196 	ret = devm_request_irq(dev, udc->irq, udc_irq, IRQF_SHARED,
197 			       "snps-udc", udc);
198 	if (ret < 0) {
199 		dev_err(dev, "Request irq %d failed for UDC\n", udc->irq);
200 		goto exit_dma;
201 	}
202 
203 	platform_set_drvdata(pdev, udc);
204 	udc->chiprev = UDC_BCM_REV;
205 
206 	if (udc_probe(udc)) {
207 		ret = -ENODEV;
208 		goto exit_dma;
209 	}
210 	dev_info(dev, "Synopsys UDC platform driver probe successful\n");
211 
212 	return 0;
213 
214 exit_dma:
215 	if (use_dma)
216 		free_dma_pools(udc);
217 exit_extcon:
218 	if (udc->edev)
219 		extcon_unregister_notifier(udc->edev, EXTCON_USB, &udc->nb);
220 exit_phy:
221 	if (udc->udc_phy) {
222 		phy_power_off(udc->udc_phy);
223 		phy_exit(udc->udc_phy);
224 	}
225 	return ret;
226 }
227 
228 static void udc_plat_remove(struct platform_device *pdev)
229 {
230 	struct udc *dev;
231 
232 	dev = platform_get_drvdata(pdev);
233 
234 	usb_del_gadget_udc(&dev->gadget);
235 	/* gadget driver must not be registered */
236 	if (WARN_ON(dev->driver))
237 		return;
238 
239 	/* dma pool cleanup */
240 	free_dma_pools(dev);
241 
242 	udc_remove(dev);
243 
244 	platform_set_drvdata(pdev, NULL);
245 
246 	phy_power_off(dev->udc_phy);
247 	phy_exit(dev->udc_phy);
248 	extcon_unregister_notifier(dev->edev, EXTCON_USB, &dev->nb);
249 
250 	dev_info(&pdev->dev, "Synopsys UDC platform driver removed\n");
251 }
252 
253 #ifdef CONFIG_PM_SLEEP
254 static int udc_plat_suspend(struct device *dev)
255 {
256 	struct udc *udc;
257 
258 	udc = dev_get_drvdata(dev);
259 	stop_udc(udc);
260 
261 	if (extcon_get_state(udc->edev, EXTCON_USB) > 0) {
262 		dev_dbg(udc->dev, "device -> idle\n");
263 		stop_udc(udc);
264 	}
265 	phy_power_off(udc->udc_phy);
266 	phy_exit(udc->udc_phy);
267 
268 	return 0;
269 }
270 
271 static int udc_plat_resume(struct device *dev)
272 {
273 	struct udc *udc;
274 	int ret;
275 
276 	udc = dev_get_drvdata(dev);
277 
278 	ret = phy_init(udc->udc_phy);
279 	if (ret) {
280 		dev_err(udc->dev, "UDC phy init failure");
281 		return ret;
282 	}
283 
284 	ret = phy_power_on(udc->udc_phy);
285 	if (ret) {
286 		dev_err(udc->dev, "UDC phy power on failure");
287 		phy_exit(udc->udc_phy);
288 		return ret;
289 	}
290 
291 	if (extcon_get_state(udc->edev, EXTCON_USB) > 0) {
292 		dev_dbg(udc->dev, "idle -> device\n");
293 		start_udc(udc);
294 	}
295 
296 	return 0;
297 }
298 static const struct dev_pm_ops udc_plat_pm_ops = {
299 	.suspend	= udc_plat_suspend,
300 	.resume		= udc_plat_resume,
301 };
302 #endif
303 
304 #if defined(CONFIG_OF)
305 static const struct of_device_id of_udc_match[] = {
306 	{ .compatible = "brcm,ns2-udc", },
307 	{ .compatible = "brcm,cygnus-udc", },
308 	{ .compatible = "brcm,iproc-udc", },
309 	{ }
310 };
311 MODULE_DEVICE_TABLE(of, of_udc_match);
312 #endif
313 
314 static struct platform_driver udc_plat_driver = {
315 	.probe		= udc_plat_probe,
316 	.remove_new	= udc_plat_remove,
317 	.driver		= {
318 		.name	= "snps-udc-plat",
319 		.of_match_table = of_match_ptr(of_udc_match),
320 #ifdef CONFIG_PM_SLEEP
321 		.pm	= &udc_plat_pm_ops,
322 #endif
323 	},
324 };
325 module_platform_driver(udc_plat_driver);
326 
327 MODULE_DESCRIPTION(UDC_MOD_DESCRIPTION);
328 MODULE_AUTHOR("Broadcom");
329 MODULE_LICENSE("GPL v2");
330