1 /*
2  * snps_udc_plat.c - Synopsys UDC Platform Driver
3  *
4  * Copyright (C) 2016 Broadcom
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation version 2.
9  *
10  * This program is distributed "as is" WITHOUT ANY WARRANTY of any
11  * kind, whether express or implied; without even the implied warranty
12  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  */
15 
16 #include <linux/extcon.h>
17 #include <linux/of_address.h>
18 #include <linux/of_irq.h>
19 #include <linux/of_gpio.h>
20 #include <linux/platform_device.h>
21 #include <linux/phy/phy.h>
22 #include <linux/module.h>
23 #include <linux/dmapool.h>
24 #include <linux/interrupt.h>
25 #include <linux/moduleparam.h>
26 #include "amd5536udc.h"
27 
28 /* description */
29 #define UDC_MOD_DESCRIPTION     "Synopsys UDC platform driver"
30 
31 void start_udc(struct udc *udc)
32 {
33 	if (udc->driver) {
34 		dev_info(udc->dev, "Connecting...\n");
35 		udc_enable_dev_setup_interrupts(udc);
36 		udc_basic_init(udc);
37 		udc->connected = 1;
38 	}
39 }
40 
41 void stop_udc(struct udc *udc)
42 {
43 	int tmp;
44 	u32 reg;
45 
46 	spin_lock(&udc->lock);
47 
48 	/* Flush the receieve fifo */
49 	reg = readl(&udc->regs->ctl);
50 	reg |= AMD_BIT(UDC_DEVCTL_SRX_FLUSH);
51 	writel(reg, &udc->regs->ctl);
52 
53 	reg = readl(&udc->regs->ctl);
54 	reg &= ~(AMD_BIT(UDC_DEVCTL_SRX_FLUSH));
55 	writel(reg, &udc->regs->ctl);
56 	dev_dbg(udc->dev, "ep rx queue flushed\n");
57 
58 	/* Mask interrupts. Required more so when the
59 	 * UDC is connected to a DRD phy.
60 	 */
61 	udc_mask_unused_interrupts(udc);
62 
63 	/* Disconnect gadget driver */
64 	if (udc->driver) {
65 		spin_unlock(&udc->lock);
66 		udc->driver->disconnect(&udc->gadget);
67 		spin_lock(&udc->lock);
68 
69 		/* empty queues */
70 		for (tmp = 0; tmp < UDC_EP_NUM; tmp++)
71 			empty_req_queue(&udc->ep[tmp]);
72 	}
73 	udc->connected = 0;
74 
75 	spin_unlock(&udc->lock);
76 	dev_info(udc->dev, "Device disconnected\n");
77 }
78 
79 void udc_drd_work(struct work_struct *work)
80 {
81 	struct udc *udc;
82 
83 	udc = container_of(to_delayed_work(work),
84 			   struct udc, drd_work);
85 
86 	if (udc->conn_type) {
87 		dev_dbg(udc->dev, "idle -> device\n");
88 		start_udc(udc);
89 	} else {
90 		dev_dbg(udc->dev, "device -> idle\n");
91 		stop_udc(udc);
92 	}
93 }
94 
95 static int usbd_connect_notify(struct notifier_block *self,
96 			       unsigned long event, void *ptr)
97 {
98 	struct udc *udc = container_of(self, struct udc, nb);
99 
100 	dev_dbg(udc->dev, "%s: event: %lu\n", __func__, event);
101 
102 	udc->conn_type = event;
103 
104 	schedule_delayed_work(&udc->drd_work, 0);
105 
106 	return NOTIFY_OK;
107 }
108 
109 static int udc_plat_probe(struct platform_device *pdev)
110 {
111 	struct device *dev = &pdev->dev;
112 	struct resource *res;
113 	struct udc *udc;
114 	int ret;
115 
116 	udc = devm_kzalloc(dev, sizeof(*udc), GFP_KERNEL);
117 	if (!udc)
118 		return -ENOMEM;
119 
120 	spin_lock_init(&udc->lock);
121 	udc->dev = dev;
122 
123 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
124 	udc->virt_addr = devm_ioremap_resource(dev, res);
125 	if (IS_ERR(udc->regs))
126 		return PTR_ERR(udc->regs);
127 
128 	/* udc csr registers base */
129 	udc->csr = udc->virt_addr + UDC_CSR_ADDR;
130 
131 	/* dev registers base */
132 	udc->regs = udc->virt_addr + UDC_DEVCFG_ADDR;
133 
134 	/* ep registers base */
135 	udc->ep_regs = udc->virt_addr + UDC_EPREGS_ADDR;
136 
137 	/* fifo's base */
138 	udc->rxfifo = (u32 __iomem *)(udc->virt_addr + UDC_RXFIFO_ADDR);
139 	udc->txfifo = (u32 __iomem *)(udc->virt_addr + UDC_TXFIFO_ADDR);
140 
141 	udc->phys_addr = (unsigned long)res->start;
142 
143 	udc->irq = irq_of_parse_and_map(dev->of_node, 0);
144 	if (udc->irq <= 0) {
145 		dev_err(dev, "Can't parse and map interrupt\n");
146 		return -EINVAL;
147 	}
148 
149 	udc->udc_phy = devm_of_phy_get_by_index(dev, dev->of_node, 0);
150 	if (IS_ERR(udc->udc_phy)) {
151 		dev_err(dev, "Failed to obtain phy from device tree\n");
152 		return PTR_ERR(udc->udc_phy);
153 	}
154 
155 	ret = phy_init(udc->udc_phy);
156 	if (ret) {
157 		dev_err(dev, "UDC phy init failed");
158 		return ret;
159 	}
160 
161 	ret = phy_power_on(udc->udc_phy);
162 	if (ret) {
163 		dev_err(dev, "UDC phy power on failed");
164 		phy_exit(udc->udc_phy);
165 		return ret;
166 	}
167 
168 	/* Register for extcon if supported */
169 	if (of_get_property(dev->of_node, "extcon", NULL)) {
170 		udc->edev = extcon_get_edev_by_phandle(dev, 0);
171 		if (IS_ERR(udc->edev)) {
172 			if (PTR_ERR(udc->edev) == -EPROBE_DEFER)
173 				return -EPROBE_DEFER;
174 			dev_err(dev, "Invalid or missing extcon\n");
175 			ret = PTR_ERR(udc->edev);
176 			goto exit_phy;
177 		}
178 
179 		udc->nb.notifier_call = usbd_connect_notify;
180 		ret = extcon_register_notifier(udc->edev, EXTCON_USB,
181 					       &udc->nb);
182 		if (ret < 0) {
183 			dev_err(dev, "Can't register extcon device\n");
184 			goto exit_phy;
185 		}
186 
187 		ret = extcon_get_cable_state_(udc->edev, EXTCON_USB);
188 		if (ret < 0) {
189 			dev_err(dev, "Can't get cable state\n");
190 			goto exit_extcon;
191 		} else if (ret) {
192 			udc->conn_type = ret;
193 		}
194 		INIT_DELAYED_WORK(&udc->drd_work, udc_drd_work);
195 	}
196 
197 	/* init dma pools */
198 	if (use_dma) {
199 		ret = init_dma_pools(udc);
200 		if (ret != 0)
201 			goto exit_extcon;
202 	}
203 
204 	ret = devm_request_irq(dev, udc->irq, udc_irq, IRQF_SHARED,
205 			       "snps-udc", udc);
206 	if (ret < 0) {
207 		dev_err(dev, "Request irq %d failed for UDC\n", udc->irq);
208 		goto exit_dma;
209 	}
210 
211 	platform_set_drvdata(pdev, udc);
212 	udc->chiprev = UDC_BCM_REV;
213 
214 	if (udc_probe(udc)) {
215 		ret = -ENODEV;
216 		goto exit_dma;
217 	}
218 	dev_info(dev, "Synopsys UDC platform driver probe successful\n");
219 
220 	return 0;
221 
222 exit_dma:
223 	if (use_dma)
224 		free_dma_pools(udc);
225 exit_extcon:
226 	if (udc->edev)
227 		extcon_unregister_notifier(udc->edev, EXTCON_USB, &udc->nb);
228 exit_phy:
229 	if (udc->udc_phy) {
230 		phy_power_off(udc->udc_phy);
231 		phy_exit(udc->udc_phy);
232 	}
233 	return ret;
234 }
235 
236 static int udc_plat_remove(struct platform_device *pdev)
237 {
238 	struct udc *dev;
239 
240 	dev = platform_get_drvdata(pdev);
241 
242 	usb_del_gadget_udc(&dev->gadget);
243 	/* gadget driver must not be registered */
244 	if (WARN_ON(dev->driver))
245 		return 0;
246 
247 	/* dma pool cleanup */
248 	free_dma_pools(dev);
249 
250 	udc_remove(dev);
251 
252 	platform_set_drvdata(pdev, NULL);
253 
254 	if (dev->drd_wq) {
255 		flush_workqueue(dev->drd_wq);
256 		destroy_workqueue(dev->drd_wq);
257 	}
258 
259 	phy_power_off(dev->udc_phy);
260 	phy_exit(dev->udc_phy);
261 	extcon_unregister_notifier(dev->edev, EXTCON_USB, &dev->nb);
262 
263 	dev_info(&pdev->dev, "Synopsys UDC platform driver removed\n");
264 
265 	return 0;
266 }
267 
268 #ifdef CONFIG_PM_SLEEP
269 static int udc_plat_suspend(struct device *dev)
270 {
271 	struct udc *udc;
272 
273 	udc = dev_get_drvdata(dev);
274 	stop_udc(udc);
275 
276 	if (extcon_get_cable_state_(udc->edev, EXTCON_USB) > 0) {
277 		dev_dbg(udc->dev, "device -> idle\n");
278 		stop_udc(udc);
279 	}
280 	phy_power_off(udc->udc_phy);
281 	phy_exit(udc->udc_phy);
282 
283 	return 0;
284 }
285 
286 static int udc_plat_resume(struct device *dev)
287 {
288 	struct udc *udc;
289 	int ret;
290 
291 	udc = dev_get_drvdata(dev);
292 
293 	ret = phy_init(udc->udc_phy);
294 	if (ret) {
295 		dev_err(udc->dev, "UDC phy init failure");
296 		return ret;
297 	}
298 
299 	ret = phy_power_on(udc->udc_phy);
300 	if (ret) {
301 		dev_err(udc->dev, "UDC phy power on failure");
302 		phy_exit(udc->udc_phy);
303 		return ret;
304 	}
305 
306 	if (extcon_get_cable_state_(udc->edev, EXTCON_USB) > 0) {
307 		dev_dbg(udc->dev, "idle -> device\n");
308 		start_udc(udc);
309 	}
310 
311 	return 0;
312 }
313 static const struct dev_pm_ops udc_plat_pm_ops = {
314 	.suspend	= udc_plat_suspend,
315 	.resume		= udc_plat_resume,
316 };
317 #endif
318 
319 #if defined(CONFIG_OF)
320 static const struct of_device_id of_udc_match[] = {
321 	{ .compatible = "brcm,ns2-udc", },
322 	{ .compatible = "brcm,cygnus-udc", },
323 	{ .compatible = "brcm,iproc-udc", },
324 	{ }
325 };
326 MODULE_DEVICE_TABLE(of, of_udc_match);
327 #endif
328 
329 static struct platform_driver udc_plat_driver = {
330 	.probe		= udc_plat_probe,
331 	.remove		= udc_plat_remove,
332 	.driver		= {
333 		.name	= "snps-udc-plat",
334 		.of_match_table = of_match_ptr(of_udc_match),
335 #ifdef CONFIG_PM_SLEEP
336 		.pm	= &udc_plat_pm_ops,
337 #endif
338 	},
339 };
340 module_platform_driver(udc_plat_driver);
341 
342 MODULE_DESCRIPTION(UDC_MOD_DESCRIPTION);
343 MODULE_AUTHOR("Broadcom");
344 MODULE_LICENSE("GPL v2");
345