xref: /linux/drivers/usb/gadget/udc/udc-xilinx.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
1 /*
2  * Xilinx USB peripheral controller driver
3  *
4  * Copyright (C) 2004 by Thomas Rathbone
5  * Copyright (C) 2005 by HP Labs
6  * Copyright (C) 2005 by David Brownell
7  * Copyright (C) 2010 - 2014 Xilinx, Inc.
8  *
9  * Some parts of this driver code is based on the driver for at91-series
10  * USB peripheral controller (at91_udc.c).
11  *
12  * This program is free software; you can redistribute it
13  * and/or modify it under the terms of the GNU General Public
14  * License as published by the Free Software Foundation;
15  * either version 2 of the License, or (at your option) any
16  * later version.
17  */
18 
19 #include <linux/delay.h>
20 #include <linux/device.h>
21 #include <linux/dma-mapping.h>
22 #include <linux/interrupt.h>
23 #include <linux/io.h>
24 #include <linux/module.h>
25 #include <linux/of_address.h>
26 #include <linux/of_device.h>
27 #include <linux/of_platform.h>
28 #include <linux/of_irq.h>
29 #include <linux/prefetch.h>
30 #include <linux/usb/ch9.h>
31 #include <linux/usb/gadget.h>
32 
33 /* Register offsets for the USB device.*/
34 #define XUSB_EP0_CONFIG_OFFSET		0x0000  /* EP0 Config Reg Offset */
35 #define XUSB_SETUP_PKT_ADDR_OFFSET	0x0080  /* Setup Packet Address */
36 #define XUSB_ADDRESS_OFFSET		0x0100  /* Address Register */
37 #define XUSB_CONTROL_OFFSET		0x0104  /* Control Register */
38 #define XUSB_STATUS_OFFSET		0x0108  /* Status Register */
39 #define XUSB_FRAMENUM_OFFSET		0x010C	/* Frame Number Register */
40 #define XUSB_IER_OFFSET			0x0110	/* Interrupt Enable Register */
41 #define XUSB_BUFFREADY_OFFSET		0x0114	/* Buffer Ready Register */
42 #define XUSB_TESTMODE_OFFSET		0x0118	/* Test Mode Register */
43 #define XUSB_DMA_RESET_OFFSET		0x0200  /* DMA Soft Reset Register */
44 #define XUSB_DMA_CONTROL_OFFSET		0x0204	/* DMA Control Register */
45 #define XUSB_DMA_DSAR_ADDR_OFFSET	0x0208	/* DMA source Address Reg */
46 #define XUSB_DMA_DDAR_ADDR_OFFSET	0x020C	/* DMA destination Addr Reg */
47 #define XUSB_DMA_LENGTH_OFFSET		0x0210	/* DMA Length Register */
48 #define XUSB_DMA_STATUS_OFFSET		0x0214	/* DMA Status Register */
49 
50 /* Endpoint Configuration Space offsets */
51 #define XUSB_EP_CFGSTATUS_OFFSET	0x00	/* Endpoint Config Status  */
52 #define XUSB_EP_BUF0COUNT_OFFSET	0x08	/* Buffer 0 Count */
53 #define XUSB_EP_BUF1COUNT_OFFSET	0x0C	/* Buffer 1 Count */
54 
55 #define XUSB_CONTROL_USB_READY_MASK	0x80000000 /* USB ready Mask */
56 #define XUSB_CONTROL_USB_RMTWAKE_MASK	0x40000000 /* Remote wake up mask */
57 
58 /* Interrupt register related masks.*/
59 #define XUSB_STATUS_GLOBAL_INTR_MASK	0x80000000 /* Global Intr Enable */
60 #define XUSB_STATUS_DMADONE_MASK	0x04000000 /* DMA done Mask */
61 #define XUSB_STATUS_DMAERR_MASK		0x02000000 /* DMA Error Mask */
62 #define XUSB_STATUS_DMABUSY_MASK	0x80000000 /* DMA Error Mask */
63 #define XUSB_STATUS_RESUME_MASK		0x01000000 /* USB Resume Mask */
64 #define XUSB_STATUS_RESET_MASK		0x00800000 /* USB Reset Mask */
65 #define XUSB_STATUS_SUSPEND_MASK	0x00400000 /* USB Suspend Mask */
66 #define XUSB_STATUS_DISCONNECT_MASK	0x00200000 /* USB Disconnect Mask */
67 #define XUSB_STATUS_FIFO_BUFF_RDY_MASK	0x00100000 /* FIFO Buff Ready Mask */
68 #define XUSB_STATUS_FIFO_BUFF_FREE_MASK	0x00080000 /* FIFO Buff Free Mask */
69 #define XUSB_STATUS_SETUP_PACKET_MASK	0x00040000 /* Setup packet received */
70 #define XUSB_STATUS_EP1_BUFF2_COMP_MASK	0x00000200 /* EP 1 Buff 2 Processed */
71 #define XUSB_STATUS_EP1_BUFF1_COMP_MASK	0x00000002 /* EP 1 Buff 1 Processed */
72 #define XUSB_STATUS_EP0_BUFF2_COMP_MASK	0x00000100 /* EP 0 Buff 2 Processed */
73 #define XUSB_STATUS_EP0_BUFF1_COMP_MASK	0x00000001 /* EP 0 Buff 1 Processed */
74 #define XUSB_STATUS_HIGH_SPEED_MASK	0x00010000 /* USB Speed Mask */
75 /* Suspend,Reset,Suspend and Disconnect Mask */
76 #define XUSB_STATUS_INTR_EVENT_MASK	0x01E00000
77 /* Buffers  completion Mask */
78 #define XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK	0x0000FEFF
79 /* Mask for buffer 0 and buffer 1 completion for all Endpoints */
80 #define XUSB_STATUS_INTR_BUFF_COMP_SHIFT_MASK	0x00000101
81 #define XUSB_STATUS_EP_BUFF2_SHIFT	8	   /* EP buffer offset */
82 
83 /* Endpoint Configuration Status Register */
84 #define XUSB_EP_CFG_VALID_MASK		0x80000000 /* Endpoint Valid bit */
85 #define XUSB_EP_CFG_STALL_MASK		0x40000000 /* Endpoint Stall bit */
86 #define XUSB_EP_CFG_DATA_TOGGLE_MASK	0x08000000 /* Endpoint Data toggle */
87 
88 /* USB device specific global configuration constants.*/
89 #define XUSB_MAX_ENDPOINTS		8	/* Maximum End Points */
90 #define XUSB_EP_NUMBER_ZERO		0	/* End point Zero */
91 /* DPRAM is the source address for DMA transfer */
92 #define XUSB_DMA_READ_FROM_DPRAM	0x80000000
93 #define XUSB_DMA_DMASR_BUSY		0x80000000 /* DMA busy */
94 #define XUSB_DMA_DMASR_ERROR		0x40000000 /* DMA Error */
95 /*
96  * When this bit is set, the DMA buffer ready bit is set by hardware upon
97  * DMA transfer completion.
98  */
99 #define XUSB_DMA_BRR_CTRL		0x40000000 /* DMA bufready ctrl bit */
100 /* Phase States */
101 #define SETUP_PHASE			0x0000	/* Setup Phase */
102 #define DATA_PHASE			0x0001  /* Data Phase */
103 #define STATUS_PHASE			0x0002  /* Status Phase */
104 
105 #define EP0_MAX_PACKET		64 /* Endpoint 0 maximum packet length */
106 #define STATUSBUFF_SIZE		2  /* Buffer size for GET_STATUS command */
107 #define EPNAME_SIZE		4  /* Buffer size for endpoint name */
108 
109 /* container_of helper macros */
110 #define to_udc(g)	 container_of((g), struct xusb_udc, gadget)
111 #define to_xusb_ep(ep)	 container_of((ep), struct xusb_ep, ep_usb)
112 #define to_xusb_req(req) container_of((req), struct xusb_req, usb_req)
113 
114 /**
115  * struct xusb_req - Xilinx USB device request structure
116  * @usb_req: Linux usb request structure
117  * @queue: usb device request queue
118  * @ep: pointer to xusb_endpoint structure
119  */
120 struct xusb_req {
121 	struct usb_request usb_req;
122 	struct list_head queue;
123 	struct xusb_ep *ep;
124 };
125 
126 /**
127  * struct xusb_ep - USB end point structure.
128  * @ep_usb: usb endpoint instance
129  * @queue: endpoint message queue
130  * @udc: xilinx usb peripheral driver instance pointer
131  * @desc: pointer to the usb endpoint descriptor
132  * @rambase: the endpoint buffer address
133  * @offset: the endpoint register offset value
134  * @name: name of the endpoint
135  * @epnumber: endpoint number
136  * @maxpacket: maximum packet size the endpoint can store
137  * @buffer0count: the size of the packet recieved in the first buffer
138  * @buffer1count: the size of the packet received in the second buffer
139  * @curbufnum: current buffer of endpoint that will be processed next
140  * @buffer0ready: the busy state of first buffer
141  * @buffer1ready: the busy state of second buffer
142  * @is_in: endpoint direction (IN or OUT)
143  * @is_iso: endpoint type(isochronous or non isochronous)
144  */
145 struct xusb_ep {
146 	struct usb_ep ep_usb;
147 	struct list_head queue;
148 	struct xusb_udc *udc;
149 	const struct usb_endpoint_descriptor *desc;
150 	u32  rambase;
151 	u32  offset;
152 	char name[4];
153 	u16  epnumber;
154 	u16  maxpacket;
155 	u16  buffer0count;
156 	u16  buffer1count;
157 	u8   curbufnum;
158 	bool buffer0ready;
159 	bool buffer1ready;
160 	bool is_in;
161 	bool is_iso;
162 };
163 
164 /**
165  * struct xusb_udc -  USB peripheral driver structure
166  * @gadget: USB gadget driver instance
167  * @ep: an array of endpoint structures
168  * @driver: pointer to the usb gadget driver instance
169  * @setup: usb_ctrlrequest structure for control requests
170  * @req: pointer to dummy request for get status command
171  * @dev: pointer to device structure in gadget
172  * @usb_state: device in suspended state or not
173  * @remote_wkp: remote wakeup enabled by host
174  * @setupseqtx: tx status
175  * @setupseqrx: rx status
176  * @addr: the usb device base address
177  * @lock: instance of spinlock
178  * @dma_enabled: flag indicating whether the dma is included in the system
179  * @read_fn: function pointer to read device registers
180  * @write_fn: function pointer to write to device registers
181  */
182 struct xusb_udc {
183 	struct usb_gadget gadget;
184 	struct xusb_ep ep[8];
185 	struct usb_gadget_driver *driver;
186 	struct usb_ctrlrequest setup;
187 	struct xusb_req *req;
188 	struct device *dev;
189 	u32 usb_state;
190 	u32 remote_wkp;
191 	u32 setupseqtx;
192 	u32 setupseqrx;
193 	void __iomem *addr;
194 	spinlock_t lock;
195 	bool dma_enabled;
196 
197 	unsigned int (*read_fn)(void __iomem *);
198 	void (*write_fn)(void __iomem *, u32, u32);
199 };
200 
201 /* Endpoint buffer start addresses in the core */
202 static u32 rambase[8] = { 0x22, 0x1000, 0x1100, 0x1200, 0x1300, 0x1400, 0x1500,
203 			  0x1600 };
204 
205 static const char driver_name[] = "xilinx-udc";
206 static const char ep0name[] = "ep0";
207 
208 /* Control endpoint configuration.*/
209 static const struct usb_endpoint_descriptor config_bulk_out_desc = {
210 	.bLength		= USB_DT_ENDPOINT_SIZE,
211 	.bDescriptorType	= USB_DT_ENDPOINT,
212 	.bEndpointAddress	= USB_DIR_OUT,
213 	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
214 	.wMaxPacketSize		= cpu_to_le16(EP0_MAX_PACKET),
215 };
216 
217 /**
218  * xudc_write32 - little endian write to device registers
219  * @addr: base addr of device registers
220  * @offset: register offset
221  * @val: data to be written
222  */
223 static void xudc_write32(void __iomem *addr, u32 offset, u32 val)
224 {
225 	iowrite32(val, addr + offset);
226 }
227 
228 /**
229  * xudc_read32 - little endian read from device registers
230  * @addr: addr of device register
231  * Return: value at addr
232  */
233 static unsigned int xudc_read32(void __iomem *addr)
234 {
235 	return ioread32(addr);
236 }
237 
238 /**
239  * xudc_write32_be - big endian write to device registers
240  * @addr: base addr of device registers
241  * @offset: register offset
242  * @val: data to be written
243  */
244 static void xudc_write32_be(void __iomem *addr, u32 offset, u32 val)
245 {
246 	iowrite32be(val, addr + offset);
247 }
248 
249 /**
250  * xudc_read32_be - big endian read from device registers
251  * @addr: addr of device register
252  * Return: value at addr
253  */
254 static unsigned int xudc_read32_be(void __iomem *addr)
255 {
256 	return ioread32be(addr);
257 }
258 
259 /**
260  * xudc_wrstatus - Sets up the usb device status stages.
261  * @udc: pointer to the usb device controller structure.
262  */
263 static void xudc_wrstatus(struct xusb_udc *udc)
264 {
265 	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
266 	u32 epcfgreg;
267 
268 	epcfgreg = udc->read_fn(udc->addr + ep0->offset)|
269 				XUSB_EP_CFG_DATA_TOGGLE_MASK;
270 	udc->write_fn(udc->addr, ep0->offset, epcfgreg);
271 	udc->write_fn(udc->addr, ep0->offset + XUSB_EP_BUF0COUNT_OFFSET, 0);
272 	udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
273 }
274 
275 /**
276  * xudc_epconfig - Configures the given endpoint.
277  * @ep: pointer to the usb device endpoint structure.
278  * @udc: pointer to the usb peripheral controller structure.
279  *
280  * This function configures a specific endpoint with the given configuration
281  * data.
282  */
283 static void xudc_epconfig(struct xusb_ep *ep, struct xusb_udc *udc)
284 {
285 	u32 epcfgreg;
286 
287 	/*
288 	 * Configure the end point direction, type, Max Packet Size and the
289 	 * EP buffer location.
290 	 */
291 	epcfgreg = ((ep->is_in << 29) | (ep->is_iso << 28) |
292 		   (ep->ep_usb.maxpacket << 15) | (ep->rambase));
293 	udc->write_fn(udc->addr, ep->offset, epcfgreg);
294 
295 	/* Set the Buffer count and the Buffer ready bits.*/
296 	udc->write_fn(udc->addr, ep->offset + XUSB_EP_BUF0COUNT_OFFSET,
297 		      ep->buffer0count);
298 	udc->write_fn(udc->addr, ep->offset + XUSB_EP_BUF1COUNT_OFFSET,
299 		      ep->buffer1count);
300 	if (ep->buffer0ready)
301 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
302 			      1 << ep->epnumber);
303 	if (ep->buffer1ready)
304 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
305 			      1 << (ep->epnumber + XUSB_STATUS_EP_BUFF2_SHIFT));
306 }
307 
308 /**
309  * xudc_start_dma - Starts DMA transfer.
310  * @ep: pointer to the usb device endpoint structure.
311  * @src: DMA source address.
312  * @dst: DMA destination address.
313  * @length: number of bytes to transfer.
314  *
315  * Return: 0 on success, error code on failure
316  *
317  * This function starts DMA transfer by writing to DMA source,
318  * destination and lenth registers.
319  */
320 static int xudc_start_dma(struct xusb_ep *ep, dma_addr_t src,
321 			  dma_addr_t dst, u32 length)
322 {
323 	struct xusb_udc *udc = ep->udc;
324 	int rc = 0;
325 	u32 timeout = 500;
326 	u32 reg;
327 
328 	/*
329 	 * Set the addresses in the DMA source and
330 	 * destination registers and then set the length
331 	 * into the DMA length register.
332 	 */
333 	udc->write_fn(udc->addr, XUSB_DMA_DSAR_ADDR_OFFSET, src);
334 	udc->write_fn(udc->addr, XUSB_DMA_DDAR_ADDR_OFFSET, dst);
335 	udc->write_fn(udc->addr, XUSB_DMA_LENGTH_OFFSET, length);
336 
337 	/*
338 	 * Wait till DMA transaction is complete and
339 	 * check whether the DMA transaction was
340 	 * successful.
341 	 */
342 	do {
343 		reg = udc->read_fn(udc->addr + XUSB_DMA_STATUS_OFFSET);
344 		if (!(reg &  XUSB_DMA_DMASR_BUSY))
345 			break;
346 
347 		/*
348 		 * We can't sleep here, because it's also called from
349 		 * interrupt context.
350 		 */
351 		timeout--;
352 		if (!timeout) {
353 			dev_err(udc->dev, "DMA timeout\n");
354 			return -ETIMEDOUT;
355 		}
356 		udelay(1);
357 	} while (1);
358 
359 	if ((udc->read_fn(udc->addr + XUSB_DMA_STATUS_OFFSET) &
360 			  XUSB_DMA_DMASR_ERROR) == XUSB_DMA_DMASR_ERROR){
361 		dev_err(udc->dev, "DMA Error\n");
362 		rc = -EINVAL;
363 	}
364 
365 	return rc;
366 }
367 
368 /**
369  * xudc_dma_send - Sends IN data using DMA.
370  * @ep: pointer to the usb device endpoint structure.
371  * @req: pointer to the usb request structure.
372  * @buffer: pointer to data to be sent.
373  * @length: number of bytes to send.
374  *
375  * Return: 0 on success, -EAGAIN if no buffer is free and error
376  *	   code on failure.
377  *
378  * This function sends data using DMA.
379  */
380 static int xudc_dma_send(struct xusb_ep *ep, struct xusb_req *req,
381 			 u8 *buffer, u32 length)
382 {
383 	u32 *eprambase;
384 	dma_addr_t src;
385 	dma_addr_t dst;
386 	struct xusb_udc *udc = ep->udc;
387 
388 	src = req->usb_req.dma + req->usb_req.actual;
389 	if (req->usb_req.length)
390 		dma_sync_single_for_device(udc->dev, src,
391 					   length, DMA_TO_DEVICE);
392 	if (!ep->curbufnum && !ep->buffer0ready) {
393 		/* Get the Buffer address and copy the transmit data.*/
394 		eprambase = (u32 __force *)(udc->addr + ep->rambase);
395 		dst = virt_to_phys(eprambase);
396 		udc->write_fn(udc->addr, ep->offset +
397 			      XUSB_EP_BUF0COUNT_OFFSET, length);
398 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
399 			      XUSB_DMA_BRR_CTRL | (1 << ep->epnumber));
400 		ep->buffer0ready = 1;
401 		ep->curbufnum = 1;
402 	} else if (ep->curbufnum && !ep->buffer1ready) {
403 		/* Get the Buffer address and copy the transmit data.*/
404 		eprambase = (u32 __force *)(udc->addr + ep->rambase +
405 			     ep->ep_usb.maxpacket);
406 		dst = virt_to_phys(eprambase);
407 		udc->write_fn(udc->addr, ep->offset +
408 			      XUSB_EP_BUF1COUNT_OFFSET, length);
409 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
410 			      XUSB_DMA_BRR_CTRL | (1 << (ep->epnumber +
411 			      XUSB_STATUS_EP_BUFF2_SHIFT)));
412 		ep->buffer1ready = 1;
413 		ep->curbufnum = 0;
414 	} else {
415 		/* None of ping pong buffers are ready currently .*/
416 		return -EAGAIN;
417 	}
418 
419 	return xudc_start_dma(ep, src, dst, length);
420 }
421 
422 /**
423  * xudc_dma_receive - Receives OUT data using DMA.
424  * @ep: pointer to the usb device endpoint structure.
425  * @req: pointer to the usb request structure.
426  * @buffer: pointer to storage buffer of received data.
427  * @length: number of bytes to receive.
428  *
429  * Return: 0 on success, -EAGAIN if no buffer is free and error
430  *	   code on failure.
431  *
432  * This function receives data using DMA.
433  */
434 static int xudc_dma_receive(struct xusb_ep *ep, struct xusb_req *req,
435 			    u8 *buffer, u32 length)
436 {
437 	u32 *eprambase;
438 	dma_addr_t src;
439 	dma_addr_t dst;
440 	struct xusb_udc *udc = ep->udc;
441 
442 	dst = req->usb_req.dma + req->usb_req.actual;
443 	if (!ep->curbufnum && !ep->buffer0ready) {
444 		/* Get the Buffer address and copy the transmit data */
445 		eprambase = (u32 __force *)(udc->addr + ep->rambase);
446 		src = virt_to_phys(eprambase);
447 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
448 			      XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
449 			      (1 << ep->epnumber));
450 		ep->buffer0ready = 1;
451 		ep->curbufnum = 1;
452 	} else if (ep->curbufnum && !ep->buffer1ready) {
453 		/* Get the Buffer address and copy the transmit data */
454 		eprambase = (u32 __force *)(udc->addr +
455 			     ep->rambase + ep->ep_usb.maxpacket);
456 		src = virt_to_phys(eprambase);
457 		udc->write_fn(udc->addr, XUSB_DMA_CONTROL_OFFSET,
458 			      XUSB_DMA_BRR_CTRL | XUSB_DMA_READ_FROM_DPRAM |
459 			      (1 << (ep->epnumber +
460 			      XUSB_STATUS_EP_BUFF2_SHIFT)));
461 		ep->buffer1ready = 1;
462 		ep->curbufnum = 0;
463 	} else {
464 		/* None of the ping-pong buffers are ready currently */
465 		return -EAGAIN;
466 	}
467 
468 	return xudc_start_dma(ep, src, dst, length);
469 }
470 
471 /**
472  * xudc_eptxrx - Transmits or receives data to or from an endpoint.
473  * @ep: pointer to the usb endpoint configuration structure.
474  * @req: pointer to the usb request structure.
475  * @bufferptr: pointer to buffer containing the data to be sent.
476  * @bufferlen: The number of data bytes to be sent.
477  *
478  * Return: 0 on success, -EAGAIN if no buffer is free.
479  *
480  * This function copies the transmit/receive data to/from the end point buffer
481  * and enables the buffer for transmission/reception.
482  */
483 static int xudc_eptxrx(struct xusb_ep *ep, struct xusb_req *req,
484 		       u8 *bufferptr, u32 bufferlen)
485 {
486 	u32 *eprambase;
487 	u32 bytestosend;
488 	int rc = 0;
489 	struct xusb_udc *udc = ep->udc;
490 
491 	bytestosend = bufferlen;
492 	if (udc->dma_enabled) {
493 		if (ep->is_in)
494 			rc = xudc_dma_send(ep, req, bufferptr, bufferlen);
495 		else
496 			rc = xudc_dma_receive(ep, req, bufferptr, bufferlen);
497 		return rc;
498 	}
499 	/* Put the transmit buffer into the correct ping-pong buffer.*/
500 	if (!ep->curbufnum && !ep->buffer0ready) {
501 		/* Get the Buffer address and copy the transmit data.*/
502 		eprambase = (u32 __force *)(udc->addr + ep->rambase);
503 		if (ep->is_in) {
504 			memcpy(eprambase, bufferptr, bytestosend);
505 			udc->write_fn(udc->addr, ep->offset +
506 				      XUSB_EP_BUF0COUNT_OFFSET, bufferlen);
507 		} else {
508 			memcpy(bufferptr, eprambase, bytestosend);
509 		}
510 		/*
511 		 * Enable the buffer for transmission.
512 		 */
513 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
514 			      1 << ep->epnumber);
515 		ep->buffer0ready = 1;
516 		ep->curbufnum = 1;
517 	} else if (ep->curbufnum && !ep->buffer1ready) {
518 		/* Get the Buffer address and copy the transmit data.*/
519 		eprambase = (u32 __force *)(udc->addr + ep->rambase +
520 			     ep->ep_usb.maxpacket);
521 		if (ep->is_in) {
522 			memcpy(eprambase, bufferptr, bytestosend);
523 			udc->write_fn(udc->addr, ep->offset +
524 				      XUSB_EP_BUF1COUNT_OFFSET, bufferlen);
525 		} else {
526 			memcpy(bufferptr, eprambase, bytestosend);
527 		}
528 		/*
529 		 * Enable the buffer for transmission.
530 		 */
531 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
532 			      1 << (ep->epnumber + XUSB_STATUS_EP_BUFF2_SHIFT));
533 		ep->buffer1ready = 1;
534 		ep->curbufnum = 0;
535 	} else {
536 		/* None of the ping-pong buffers are ready currently */
537 		return -EAGAIN;
538 	}
539 	return rc;
540 }
541 
542 /**
543  * xudc_done - Exeutes the endpoint data transfer completion tasks.
544  * @ep: pointer to the usb device endpoint structure.
545  * @req: pointer to the usb request structure.
546  * @status: Status of the data transfer.
547  *
548  * Deletes the message from the queue and updates data transfer completion
549  * status.
550  */
551 static void xudc_done(struct xusb_ep *ep, struct xusb_req *req, int status)
552 {
553 	struct xusb_udc *udc = ep->udc;
554 
555 	list_del_init(&req->queue);
556 
557 	if (req->usb_req.status == -EINPROGRESS)
558 		req->usb_req.status = status;
559 	else
560 		status = req->usb_req.status;
561 
562 	if (status && status != -ESHUTDOWN)
563 		dev_dbg(udc->dev, "%s done %p, status %d\n",
564 			ep->ep_usb.name, req, status);
565 	/* unmap request if DMA is present*/
566 	if (udc->dma_enabled && ep->epnumber && req->usb_req.length)
567 		usb_gadget_unmap_request(&udc->gadget, &req->usb_req,
568 					 ep->is_in);
569 
570 	if (req->usb_req.complete) {
571 		spin_unlock(&udc->lock);
572 		req->usb_req.complete(&ep->ep_usb, &req->usb_req);
573 		spin_lock(&udc->lock);
574 	}
575 }
576 
577 /**
578  * xudc_read_fifo - Reads the data from the given endpoint buffer.
579  * @ep: pointer to the usb device endpoint structure.
580  * @req: pointer to the usb request structure.
581  *
582  * Return: 0 if request is completed and -EAGAIN if not completed.
583  *
584  * Pulls OUT packet data from the endpoint buffer.
585  */
586 static int xudc_read_fifo(struct xusb_ep *ep, struct xusb_req *req)
587 {
588 	u8 *buf;
589 	u32 is_short, count, bufferspace;
590 	u8 bufoffset;
591 	u8 two_pkts = 0;
592 	int ret;
593 	int retval = -EAGAIN;
594 	struct xusb_udc *udc = ep->udc;
595 
596 	if (ep->buffer0ready && ep->buffer1ready) {
597 		dev_dbg(udc->dev, "Packet NOT ready!\n");
598 		return retval;
599 	}
600 top:
601 	if (ep->curbufnum)
602 		bufoffset = XUSB_EP_BUF1COUNT_OFFSET;
603 	else
604 		bufoffset = XUSB_EP_BUF0COUNT_OFFSET;
605 
606 	count = udc->read_fn(udc->addr + ep->offset + bufoffset);
607 
608 	if (!ep->buffer0ready && !ep->buffer1ready)
609 		two_pkts = 1;
610 
611 	buf = req->usb_req.buf + req->usb_req.actual;
612 	prefetchw(buf);
613 	bufferspace = req->usb_req.length - req->usb_req.actual;
614 	is_short = count < ep->ep_usb.maxpacket;
615 
616 	if (unlikely(!bufferspace)) {
617 		/*
618 		 * This happens when the driver's buffer
619 		 * is smaller than what the host sent.
620 		 * discard the extra data.
621 		 */
622 		if (req->usb_req.status != -EOVERFLOW)
623 			dev_dbg(udc->dev, "%s overflow %d\n",
624 				ep->ep_usb.name, count);
625 		req->usb_req.status = -EOVERFLOW;
626 		xudc_done(ep, req, -EOVERFLOW);
627 		return 0;
628 	}
629 
630 	ret = xudc_eptxrx(ep, req, buf, count);
631 	switch (ret) {
632 	case 0:
633 		req->usb_req.actual += min(count, bufferspace);
634 		dev_dbg(udc->dev, "read %s, %d bytes%s req %p %d/%d\n",
635 			ep->ep_usb.name, count, is_short ? "/S" : "", req,
636 			req->usb_req.actual, req->usb_req.length);
637 		bufferspace -= count;
638 		/* Completion */
639 		if ((req->usb_req.actual == req->usb_req.length) || is_short) {
640 			if (udc->dma_enabled && req->usb_req.length)
641 				dma_sync_single_for_cpu(udc->dev,
642 							req->usb_req.dma,
643 							req->usb_req.actual,
644 							DMA_FROM_DEVICE);
645 			xudc_done(ep, req, 0);
646 			return 0;
647 		}
648 		if (two_pkts) {
649 			two_pkts = 0;
650 			goto top;
651 		}
652 		break;
653 	case -EAGAIN:
654 		dev_dbg(udc->dev, "receive busy\n");
655 		break;
656 	case -EINVAL:
657 	case -ETIMEDOUT:
658 		/* DMA error, dequeue the request */
659 		xudc_done(ep, req, -ECONNRESET);
660 		retval = 0;
661 		break;
662 	}
663 
664 	return retval;
665 }
666 
667 /**
668  * xudc_write_fifo - Writes data into the given endpoint buffer.
669  * @ep: pointer to the usb device endpoint structure.
670  * @req: pointer to the usb request structure.
671  *
672  * Return: 0 if request is completed and -EAGAIN if not completed.
673  *
674  * Loads endpoint buffer for an IN packet.
675  */
676 static int xudc_write_fifo(struct xusb_ep *ep, struct xusb_req *req)
677 {
678 	u32 max;
679 	u32 length;
680 	int ret;
681 	int retval = -EAGAIN;
682 	struct xusb_udc *udc = ep->udc;
683 	int is_last, is_short = 0;
684 	u8 *buf;
685 
686 	max = le16_to_cpu(ep->desc->wMaxPacketSize);
687 	buf = req->usb_req.buf + req->usb_req.actual;
688 	prefetch(buf);
689 	length = req->usb_req.length - req->usb_req.actual;
690 	length = min(length, max);
691 
692 	ret = xudc_eptxrx(ep, req, buf, length);
693 	switch (ret) {
694 	case 0:
695 		req->usb_req.actual += length;
696 		if (unlikely(length != max)) {
697 			is_last = is_short = 1;
698 		} else {
699 			if (likely(req->usb_req.length !=
700 				   req->usb_req.actual) || req->usb_req.zero)
701 				is_last = 0;
702 			else
703 				is_last = 1;
704 		}
705 		dev_dbg(udc->dev, "%s: wrote %s %d bytes%s%s %d left %p\n",
706 			__func__, ep->ep_usb.name, length, is_last ? "/L" : "",
707 			is_short ? "/S" : "",
708 			req->usb_req.length - req->usb_req.actual, req);
709 		/* completion */
710 		if (is_last) {
711 			xudc_done(ep, req, 0);
712 			retval = 0;
713 		}
714 		break;
715 	case -EAGAIN:
716 		dev_dbg(udc->dev, "Send busy\n");
717 		break;
718 	case -EINVAL:
719 	case -ETIMEDOUT:
720 		/* DMA error, dequeue the request */
721 		xudc_done(ep, req, -ECONNRESET);
722 		retval = 0;
723 		break;
724 	}
725 
726 	return retval;
727 }
728 
729 /**
730  * xudc_nuke - Cleans up the data transfer message list.
731  * @ep: pointer to the usb device endpoint structure.
732  * @status: Status of the data transfer.
733  */
734 static void xudc_nuke(struct xusb_ep *ep, int status)
735 {
736 	struct xusb_req *req;
737 
738 	while (!list_empty(&ep->queue)) {
739 		req = list_first_entry(&ep->queue, struct xusb_req, queue);
740 		xudc_done(ep, req, status);
741 	}
742 }
743 
744 /**
745  * xudc_ep_set_halt - Stalls/unstalls the given endpoint.
746  * @_ep: pointer to the usb device endpoint structure.
747  * @value: value to indicate stall/unstall.
748  *
749  * Return: 0 for success and error value on failure
750  */
751 static int xudc_ep_set_halt(struct usb_ep *_ep, int value)
752 {
753 	struct xusb_ep *ep = to_xusb_ep(_ep);
754 	struct xusb_udc *udc;
755 	unsigned long flags;
756 	u32 epcfgreg;
757 
758 	if (!_ep || (!ep->desc && ep->epnumber)) {
759 		pr_debug("%s: bad ep or descriptor\n", __func__);
760 		return -EINVAL;
761 	}
762 	udc = ep->udc;
763 
764 	if (ep->is_in && (!list_empty(&ep->queue)) && value) {
765 		dev_dbg(udc->dev, "requests pending can't halt\n");
766 		return -EAGAIN;
767 	}
768 
769 	if (ep->buffer0ready || ep->buffer1ready) {
770 		dev_dbg(udc->dev, "HW buffers busy can't halt\n");
771 		return -EAGAIN;
772 	}
773 
774 	spin_lock_irqsave(&udc->lock, flags);
775 
776 	if (value) {
777 		/* Stall the device.*/
778 		epcfgreg = udc->read_fn(udc->addr + ep->offset);
779 		epcfgreg |= XUSB_EP_CFG_STALL_MASK;
780 		udc->write_fn(udc->addr, ep->offset, epcfgreg);
781 	} else {
782 		/* Unstall the device.*/
783 		epcfgreg = udc->read_fn(udc->addr + ep->offset);
784 		epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
785 		udc->write_fn(udc->addr, ep->offset, epcfgreg);
786 		if (ep->epnumber) {
787 			/* Reset the toggle bit.*/
788 			epcfgreg = udc->read_fn(ep->udc->addr + ep->offset);
789 			epcfgreg &= ~XUSB_EP_CFG_DATA_TOGGLE_MASK;
790 			udc->write_fn(udc->addr, ep->offset, epcfgreg);
791 		}
792 	}
793 
794 	spin_unlock_irqrestore(&udc->lock, flags);
795 	return 0;
796 }
797 
798 /**
799  * xudc_ep_enable - Enables the given endpoint.
800  * @ep: pointer to the xusb endpoint structure.
801  * @desc: pointer to usb endpoint descriptor.
802  *
803  * Return: 0 for success and error value on failure
804  */
805 static int __xudc_ep_enable(struct xusb_ep *ep,
806 			    const struct usb_endpoint_descriptor *desc)
807 {
808 	struct xusb_udc *udc = ep->udc;
809 	u32 tmp;
810 	u32 epcfg;
811 	u32 ier;
812 	u16 maxpacket;
813 
814 	ep->is_in = ((desc->bEndpointAddress & USB_DIR_IN) != 0);
815 	/* Bit 3...0:endpoint number */
816 	ep->epnumber = (desc->bEndpointAddress & 0x0f);
817 	ep->desc = desc;
818 	ep->ep_usb.desc = desc;
819 	tmp = desc->bmAttributes & USB_ENDPOINT_XFERTYPE_MASK;
820 	ep->ep_usb.maxpacket = maxpacket = le16_to_cpu(desc->wMaxPacketSize);
821 
822 	switch (tmp) {
823 	case USB_ENDPOINT_XFER_CONTROL:
824 		dev_dbg(udc->dev, "only one control endpoint\n");
825 		/* NON- ISO */
826 		ep->is_iso = 0;
827 		return -EINVAL;
828 	case USB_ENDPOINT_XFER_INT:
829 		/* NON- ISO */
830 		ep->is_iso = 0;
831 		if (maxpacket > 64) {
832 			dev_dbg(udc->dev, "bogus maxpacket %d\n", maxpacket);
833 			return -EINVAL;
834 		}
835 		break;
836 	case USB_ENDPOINT_XFER_BULK:
837 		/* NON- ISO */
838 		ep->is_iso = 0;
839 		if (!(is_power_of_2(maxpacket) && maxpacket >= 8 &&
840 				maxpacket <= 512)) {
841 			dev_dbg(udc->dev, "bogus maxpacket %d\n", maxpacket);
842 			return -EINVAL;
843 		}
844 		break;
845 	case USB_ENDPOINT_XFER_ISOC:
846 		/* ISO */
847 		ep->is_iso = 1;
848 		break;
849 	}
850 
851 	ep->buffer0ready = 0;
852 	ep->buffer1ready = 0;
853 	ep->curbufnum = 0;
854 	ep->rambase = rambase[ep->epnumber];
855 	xudc_epconfig(ep, udc);
856 
857 	dev_dbg(udc->dev, "Enable Endpoint %d max pkt is %d\n",
858 		ep->epnumber, maxpacket);
859 
860 	/* Enable the End point.*/
861 	epcfg = udc->read_fn(udc->addr + ep->offset);
862 	epcfg |= XUSB_EP_CFG_VALID_MASK;
863 	udc->write_fn(udc->addr, ep->offset, epcfg);
864 	if (ep->epnumber)
865 		ep->rambase <<= 2;
866 
867 	/* Enable buffer completion interrupts for endpoint */
868 	ier = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
869 	ier |= (XUSB_STATUS_INTR_BUFF_COMP_SHIFT_MASK << ep->epnumber);
870 	udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
871 
872 	/* for OUT endpoint set buffers ready to receive */
873 	if (ep->epnumber && !ep->is_in) {
874 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
875 			      1 << ep->epnumber);
876 		ep->buffer0ready = 1;
877 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET,
878 			     (1 << (ep->epnumber +
879 			      XUSB_STATUS_EP_BUFF2_SHIFT)));
880 		ep->buffer1ready = 1;
881 	}
882 
883 	return 0;
884 }
885 
886 /**
887  * xudc_ep_enable - Enables the given endpoint.
888  * @_ep: pointer to the usb endpoint structure.
889  * @desc: pointer to usb endpoint descriptor.
890  *
891  * Return: 0 for success and error value on failure
892  */
893 static int xudc_ep_enable(struct usb_ep *_ep,
894 			  const struct usb_endpoint_descriptor *desc)
895 {
896 	struct xusb_ep *ep;
897 	struct xusb_udc *udc;
898 	unsigned long flags;
899 	int ret;
900 
901 	if (!_ep || !desc || desc->bDescriptorType != USB_DT_ENDPOINT) {
902 		pr_debug("%s: bad ep or descriptor\n", __func__);
903 		return -EINVAL;
904 	}
905 
906 	ep = to_xusb_ep(_ep);
907 	udc = ep->udc;
908 
909 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
910 		dev_dbg(udc->dev, "bogus device state\n");
911 		return -ESHUTDOWN;
912 	}
913 
914 	spin_lock_irqsave(&udc->lock, flags);
915 	ret = __xudc_ep_enable(ep, desc);
916 	spin_unlock_irqrestore(&udc->lock, flags);
917 
918 	return ret;
919 }
920 
921 /**
922  * xudc_ep_disable - Disables the given endpoint.
923  * @_ep: pointer to the usb endpoint structure.
924  *
925  * Return: 0 for success and error value on failure
926  */
927 static int xudc_ep_disable(struct usb_ep *_ep)
928 {
929 	struct xusb_ep *ep;
930 	unsigned long flags;
931 	u32 epcfg;
932 	struct xusb_udc *udc;
933 
934 	if (!_ep) {
935 		pr_debug("%s: invalid ep\n", __func__);
936 		return -EINVAL;
937 	}
938 
939 	ep = to_xusb_ep(_ep);
940 	udc = ep->udc;
941 
942 	spin_lock_irqsave(&udc->lock, flags);
943 
944 	xudc_nuke(ep, -ESHUTDOWN);
945 
946 	/* Restore the endpoint's pristine config */
947 	ep->desc = NULL;
948 	ep->ep_usb.desc = NULL;
949 
950 	dev_dbg(udc->dev, "USB Ep %d disable\n ", ep->epnumber);
951 	/* Disable the endpoint.*/
952 	epcfg = udc->read_fn(udc->addr + ep->offset);
953 	epcfg &= ~XUSB_EP_CFG_VALID_MASK;
954 	udc->write_fn(udc->addr, ep->offset, epcfg);
955 
956 	spin_unlock_irqrestore(&udc->lock, flags);
957 	return 0;
958 }
959 
960 /**
961  * xudc_ep_alloc_request - Initializes the request queue.
962  * @_ep: pointer to the usb endpoint structure.
963  * @gfp_flags: Flags related to the request call.
964  *
965  * Return: pointer to request structure on success and a NULL on failure.
966  */
967 static struct usb_request *xudc_ep_alloc_request(struct usb_ep *_ep,
968 						 gfp_t gfp_flags)
969 {
970 	struct xusb_ep *ep = to_xusb_ep(_ep);
971 	struct xusb_udc *udc;
972 	struct xusb_req *req;
973 
974 	udc = ep->udc;
975 	req = kzalloc(sizeof(*req), gfp_flags);
976 	if (!req) {
977 		dev_err(udc->dev, "%s:not enough memory", __func__);
978 		return NULL;
979 	}
980 
981 	req->ep = ep;
982 	INIT_LIST_HEAD(&req->queue);
983 	return &req->usb_req;
984 }
985 
986 /**
987  * xudc_free_request - Releases the request from queue.
988  * @_ep: pointer to the usb device endpoint structure.
989  * @_req: pointer to the usb request structure.
990  */
991 static void xudc_free_request(struct usb_ep *_ep, struct usb_request *_req)
992 {
993 	struct xusb_req *req = to_xusb_req(_req);
994 
995 	kfree(req);
996 }
997 
998 /**
999  * xudc_ep0_queue - Adds the request to endpoint 0 queue.
1000  * @ep0: pointer to the xusb endpoint 0 structure.
1001  * @req: pointer to the xusb request structure.
1002  *
1003  * Return: 0 for success and error value on failure
1004  */
1005 static int __xudc_ep0_queue(struct xusb_ep *ep0, struct xusb_req *req)
1006 {
1007 	struct xusb_udc *udc = ep0->udc;
1008 	u32 length;
1009 	u8 *corebuf;
1010 
1011 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
1012 		dev_dbg(udc->dev, "%s, bogus device state\n", __func__);
1013 		return -EINVAL;
1014 	}
1015 	if (!list_empty(&ep0->queue)) {
1016 		dev_dbg(udc->dev, "%s:ep0 busy\n", __func__);
1017 		return -EBUSY;
1018 	}
1019 
1020 	req->usb_req.status = -EINPROGRESS;
1021 	req->usb_req.actual = 0;
1022 
1023 	list_add_tail(&req->queue, &ep0->queue);
1024 
1025 	if (udc->setup.bRequestType & USB_DIR_IN) {
1026 		prefetch(req->usb_req.buf);
1027 		length = req->usb_req.length;
1028 		corebuf = (void __force *) ((ep0->rambase << 2) +
1029 			   udc->addr);
1030 		length = req->usb_req.actual = min_t(u32, length,
1031 						     EP0_MAX_PACKET);
1032 		memcpy(corebuf, req->usb_req.buf, length);
1033 		udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, length);
1034 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1035 	} else {
1036 		if (udc->setup.wLength) {
1037 			/* Enable EP0 buffer to receive data */
1038 			udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, 0);
1039 			udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1040 		} else {
1041 			xudc_wrstatus(udc);
1042 		}
1043 	}
1044 
1045 	return 0;
1046 }
1047 
1048 /**
1049  * xudc_ep0_queue - Adds the request to endpoint 0 queue.
1050  * @_ep: pointer to the usb endpoint 0 structure.
1051  * @_req: pointer to the usb request structure.
1052  * @gfp_flags: Flags related to the request call.
1053  *
1054  * Return: 0 for success and error value on failure
1055  */
1056 static int xudc_ep0_queue(struct usb_ep *_ep, struct usb_request *_req,
1057 			  gfp_t gfp_flags)
1058 {
1059 	struct xusb_req *req	= to_xusb_req(_req);
1060 	struct xusb_ep	*ep0	= to_xusb_ep(_ep);
1061 	struct xusb_udc *udc	= ep0->udc;
1062 	unsigned long flags;
1063 	int ret;
1064 
1065 	spin_lock_irqsave(&udc->lock, flags);
1066 	ret = __xudc_ep0_queue(ep0, req);
1067 	spin_unlock_irqrestore(&udc->lock, flags);
1068 
1069 	return ret;
1070 }
1071 
1072 /**
1073  * xudc_ep_queue - Adds the request to endpoint queue.
1074  * @_ep: pointer to the usb endpoint structure.
1075  * @_req: pointer to the usb request structure.
1076  * @gfp_flags: Flags related to the request call.
1077  *
1078  * Return: 0 for success and error value on failure
1079  */
1080 static int xudc_ep_queue(struct usb_ep *_ep, struct usb_request *_req,
1081 			 gfp_t gfp_flags)
1082 {
1083 	struct xusb_req *req = to_xusb_req(_req);
1084 	struct xusb_ep	*ep  = to_xusb_ep(_ep);
1085 	struct xusb_udc *udc = ep->udc;
1086 	int  ret;
1087 	unsigned long flags;
1088 
1089 	if (!ep->desc) {
1090 		dev_dbg(udc->dev, "%s:queing request to disabled %s\n",
1091 			__func__, ep->name);
1092 		return -ESHUTDOWN;
1093 	}
1094 
1095 	if (!udc->driver || udc->gadget.speed == USB_SPEED_UNKNOWN) {
1096 		dev_dbg(udc->dev, "%s, bogus device state\n", __func__);
1097 		return -EINVAL;
1098 	}
1099 
1100 	spin_lock_irqsave(&udc->lock, flags);
1101 
1102 	_req->status = -EINPROGRESS;
1103 	_req->actual = 0;
1104 
1105 	if (udc->dma_enabled) {
1106 		ret = usb_gadget_map_request(&udc->gadget, &req->usb_req,
1107 					     ep->is_in);
1108 		if (ret) {
1109 			dev_dbg(udc->dev, "gadget_map failed ep%d\n",
1110 				ep->epnumber);
1111 			spin_unlock_irqrestore(&udc->lock, flags);
1112 			return -EAGAIN;
1113 		}
1114 	}
1115 
1116 	if (list_empty(&ep->queue)) {
1117 		if (ep->is_in) {
1118 			dev_dbg(udc->dev, "xudc_write_fifo from ep_queue\n");
1119 			if (!xudc_write_fifo(ep, req))
1120 				req = NULL;
1121 		} else {
1122 			dev_dbg(udc->dev, "xudc_read_fifo from ep_queue\n");
1123 			if (!xudc_read_fifo(ep, req))
1124 				req = NULL;
1125 		}
1126 	}
1127 
1128 	if (req != NULL)
1129 		list_add_tail(&req->queue, &ep->queue);
1130 
1131 	spin_unlock_irqrestore(&udc->lock, flags);
1132 	return 0;
1133 }
1134 
1135 /**
1136  * xudc_ep_dequeue - Removes the request from the queue.
1137  * @_ep: pointer to the usb device endpoint structure.
1138  * @_req: pointer to the usb request structure.
1139  *
1140  * Return: 0 for success and error value on failure
1141  */
1142 static int xudc_ep_dequeue(struct usb_ep *_ep, struct usb_request *_req)
1143 {
1144 	struct xusb_ep *ep	= to_xusb_ep(_ep);
1145 	struct xusb_req *req	= to_xusb_req(_req);
1146 	struct xusb_udc *udc	= ep->udc;
1147 	unsigned long flags;
1148 
1149 	spin_lock_irqsave(&udc->lock, flags);
1150 	/* Make sure it's actually queued on this endpoint */
1151 	list_for_each_entry(req, &ep->queue, queue) {
1152 		if (&req->usb_req == _req)
1153 			break;
1154 	}
1155 	if (&req->usb_req != _req) {
1156 		spin_unlock_irqrestore(&ep->udc->lock, flags);
1157 		return -EINVAL;
1158 	}
1159 	xudc_done(ep, req, -ECONNRESET);
1160 	spin_unlock_irqrestore(&udc->lock, flags);
1161 
1162 	return 0;
1163 }
1164 
1165 /**
1166  * xudc_ep0_enable - Enables the given endpoint.
1167  * @ep: pointer to the usb endpoint structure.
1168  * @desc: pointer to usb endpoint descriptor.
1169  *
1170  * Return: error always.
1171  *
1172  * endpoint 0 enable should not be called by gadget layer.
1173  */
1174 static int xudc_ep0_enable(struct usb_ep *ep,
1175 			   const struct usb_endpoint_descriptor *desc)
1176 {
1177 	return -EINVAL;
1178 }
1179 
1180 /**
1181  * xudc_ep0_disable - Disables the given endpoint.
1182  * @ep: pointer to the usb endpoint structure.
1183  *
1184  * Return: error always.
1185  *
1186  * endpoint 0 disable should not be called by gadget layer.
1187  */
1188 static int xudc_ep0_disable(struct usb_ep *ep)
1189 {
1190 	return -EINVAL;
1191 }
1192 
1193 static const struct usb_ep_ops xusb_ep0_ops = {
1194 	.enable		= xudc_ep0_enable,
1195 	.disable	= xudc_ep0_disable,
1196 	.alloc_request	= xudc_ep_alloc_request,
1197 	.free_request	= xudc_free_request,
1198 	.queue		= xudc_ep0_queue,
1199 	.dequeue	= xudc_ep_dequeue,
1200 	.set_halt	= xudc_ep_set_halt,
1201 };
1202 
1203 static const struct usb_ep_ops xusb_ep_ops = {
1204 	.enable		= xudc_ep_enable,
1205 	.disable	= xudc_ep_disable,
1206 	.alloc_request	= xudc_ep_alloc_request,
1207 	.free_request	= xudc_free_request,
1208 	.queue		= xudc_ep_queue,
1209 	.dequeue	= xudc_ep_dequeue,
1210 	.set_halt	= xudc_ep_set_halt,
1211 };
1212 
1213 /**
1214  * xudc_get_frame - Reads the current usb frame number.
1215  * @gadget: pointer to the usb gadget structure.
1216  *
1217  * Return: current frame number for success and error value on failure.
1218  */
1219 static int xudc_get_frame(struct usb_gadget *gadget)
1220 {
1221 	struct xusb_udc *udc;
1222 	int frame;
1223 
1224 	if (!gadget)
1225 		return -ENODEV;
1226 
1227 	udc = to_udc(gadget);
1228 	frame = udc->read_fn(udc->addr + XUSB_FRAMENUM_OFFSET);
1229 	return frame;
1230 }
1231 
1232 /**
1233  * xudc_wakeup - Send remote wakeup signal to host
1234  * @gadget: pointer to the usb gadget structure.
1235  *
1236  * Return: 0 on success and error on failure
1237  */
1238 static int xudc_wakeup(struct usb_gadget *gadget)
1239 {
1240 	struct xusb_udc *udc = to_udc(gadget);
1241 	u32 crtlreg;
1242 	int status = -EINVAL;
1243 	unsigned long flags;
1244 
1245 	spin_lock_irqsave(&udc->lock, flags);
1246 
1247 	/* Remote wake up not enabled by host */
1248 	if (!udc->remote_wkp)
1249 		goto done;
1250 
1251 	crtlreg = udc->read_fn(udc->addr + XUSB_CONTROL_OFFSET);
1252 	crtlreg |= XUSB_CONTROL_USB_RMTWAKE_MASK;
1253 	/* set remote wake up bit */
1254 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
1255 	/*
1256 	 * wait for a while and reset remote wake up bit since this bit
1257 	 * is not cleared by HW after sending remote wakeup to host.
1258 	 */
1259 	mdelay(2);
1260 
1261 	crtlreg &= ~XUSB_CONTROL_USB_RMTWAKE_MASK;
1262 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
1263 	status = 0;
1264 done:
1265 	spin_unlock_irqrestore(&udc->lock, flags);
1266 	return status;
1267 }
1268 
1269 /**
1270  * xudc_pullup - start/stop USB traffic
1271  * @gadget: pointer to the usb gadget structure.
1272  * @is_on: flag to start or stop
1273  *
1274  * Return: 0 always
1275  *
1276  * This function starts/stops SIE engine of IP based on is_on.
1277  */
1278 static int xudc_pullup(struct usb_gadget *gadget, int is_on)
1279 {
1280 	struct xusb_udc *udc = to_udc(gadget);
1281 	unsigned long flags;
1282 	u32 crtlreg;
1283 
1284 	spin_lock_irqsave(&udc->lock, flags);
1285 
1286 	crtlreg = udc->read_fn(udc->addr + XUSB_CONTROL_OFFSET);
1287 	if (is_on)
1288 		crtlreg |= XUSB_CONTROL_USB_READY_MASK;
1289 	else
1290 		crtlreg &= ~XUSB_CONTROL_USB_READY_MASK;
1291 
1292 	udc->write_fn(udc->addr, XUSB_CONTROL_OFFSET, crtlreg);
1293 
1294 	spin_unlock_irqrestore(&udc->lock, flags);
1295 
1296 	return 0;
1297 }
1298 
1299 /**
1300  * xudc_eps_init - initialize endpoints.
1301  * @udc: pointer to the usb device controller structure.
1302  */
1303 static void xudc_eps_init(struct xusb_udc *udc)
1304 {
1305 	u32 ep_number;
1306 
1307 	INIT_LIST_HEAD(&udc->gadget.ep_list);
1308 
1309 	for (ep_number = 0; ep_number < XUSB_MAX_ENDPOINTS; ep_number++) {
1310 		struct xusb_ep *ep = &udc->ep[ep_number];
1311 
1312 		if (ep_number) {
1313 			list_add_tail(&ep->ep_usb.ep_list,
1314 				      &udc->gadget.ep_list);
1315 			usb_ep_set_maxpacket_limit(&ep->ep_usb,
1316 						  (unsigned short) ~0);
1317 			snprintf(ep->name, EPNAME_SIZE, "ep%d", ep_number);
1318 			ep->ep_usb.name = ep->name;
1319 			ep->ep_usb.ops = &xusb_ep_ops;
1320 		} else {
1321 			ep->ep_usb.name = ep0name;
1322 			usb_ep_set_maxpacket_limit(&ep->ep_usb, EP0_MAX_PACKET);
1323 			ep->ep_usb.ops = &xusb_ep0_ops;
1324 		}
1325 
1326 		ep->udc = udc;
1327 		ep->epnumber = ep_number;
1328 		ep->desc = NULL;
1329 		/*
1330 		 * The configuration register address offset between
1331 		 * each endpoint is 0x10.
1332 		 */
1333 		ep->offset = XUSB_EP0_CONFIG_OFFSET + (ep_number * 0x10);
1334 		ep->is_in = 0;
1335 		ep->is_iso = 0;
1336 		ep->maxpacket = 0;
1337 		xudc_epconfig(ep, udc);
1338 
1339 		/* Initialize one queue per endpoint */
1340 		INIT_LIST_HEAD(&ep->queue);
1341 	}
1342 }
1343 
1344 /**
1345  * xudc_stop_activity - Stops any further activity on the device.
1346  * @udc: pointer to the usb device controller structure.
1347  */
1348 static void xudc_stop_activity(struct xusb_udc *udc)
1349 {
1350 	int i;
1351 	struct xusb_ep *ep;
1352 
1353 	for (i = 0; i < XUSB_MAX_ENDPOINTS; i++) {
1354 		ep = &udc->ep[i];
1355 		xudc_nuke(ep, -ESHUTDOWN);
1356 	}
1357 }
1358 
1359 /**
1360  * xudc_start - Starts the device.
1361  * @gadget: pointer to the usb gadget structure
1362  * @driver: pointer to gadget driver structure
1363  *
1364  * Return: zero on success and error on failure
1365  */
1366 static int xudc_start(struct usb_gadget *gadget,
1367 		      struct usb_gadget_driver *driver)
1368 {
1369 	struct xusb_udc *udc	= to_udc(gadget);
1370 	struct xusb_ep *ep0	= &udc->ep[XUSB_EP_NUMBER_ZERO];
1371 	const struct usb_endpoint_descriptor *desc = &config_bulk_out_desc;
1372 	unsigned long flags;
1373 	int ret = 0;
1374 
1375 	spin_lock_irqsave(&udc->lock, flags);
1376 
1377 	if (udc->driver) {
1378 		dev_err(udc->dev, "%s is already bound to %s\n",
1379 			udc->gadget.name, udc->driver->driver.name);
1380 		ret = -EBUSY;
1381 		goto err;
1382 	}
1383 
1384 	/* hook up the driver */
1385 	udc->driver = driver;
1386 	udc->gadget.speed = driver->max_speed;
1387 
1388 	/* Enable the control endpoint. */
1389 	ret = __xudc_ep_enable(ep0, desc);
1390 
1391 	/* Set device address and remote wakeup to 0 */
1392 	udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
1393 	udc->remote_wkp = 0;
1394 err:
1395 	spin_unlock_irqrestore(&udc->lock, flags);
1396 	return ret;
1397 }
1398 
1399 /**
1400  * xudc_stop - stops the device.
1401  * @gadget: pointer to the usb gadget structure
1402  * @driver: pointer to usb gadget driver structure
1403  *
1404  * Return: zero always
1405  */
1406 static int xudc_stop(struct usb_gadget *gadget)
1407 {
1408 	struct xusb_udc *udc = to_udc(gadget);
1409 	unsigned long flags;
1410 
1411 	spin_lock_irqsave(&udc->lock, flags);
1412 
1413 	udc->gadget.speed = USB_SPEED_UNKNOWN;
1414 	udc->driver = NULL;
1415 
1416 	/* Set device address and remote wakeup to 0 */
1417 	udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
1418 	udc->remote_wkp = 0;
1419 
1420 	xudc_stop_activity(udc);
1421 
1422 	spin_unlock_irqrestore(&udc->lock, flags);
1423 
1424 	return 0;
1425 }
1426 
1427 static const struct usb_gadget_ops xusb_udc_ops = {
1428 	.get_frame	= xudc_get_frame,
1429 	.wakeup		= xudc_wakeup,
1430 	.pullup		= xudc_pullup,
1431 	.udc_start	= xudc_start,
1432 	.udc_stop	= xudc_stop,
1433 };
1434 
1435 /**
1436  * xudc_clear_stall_all_ep - clears stall of every endpoint.
1437  * @udc: pointer to the udc structure.
1438  */
1439 static void xudc_clear_stall_all_ep(struct xusb_udc *udc)
1440 {
1441 	struct xusb_ep *ep;
1442 	u32 epcfgreg;
1443 	int i;
1444 
1445 	for (i = 0; i < XUSB_MAX_ENDPOINTS; i++) {
1446 		ep = &udc->ep[i];
1447 		epcfgreg = udc->read_fn(udc->addr + ep->offset);
1448 		epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
1449 		udc->write_fn(udc->addr, ep->offset, epcfgreg);
1450 		if (ep->epnumber) {
1451 			/* Reset the toggle bit.*/
1452 			epcfgreg = udc->read_fn(udc->addr + ep->offset);
1453 			epcfgreg &= ~XUSB_EP_CFG_DATA_TOGGLE_MASK;
1454 			udc->write_fn(udc->addr, ep->offset, epcfgreg);
1455 		}
1456 	}
1457 }
1458 
1459 /**
1460  * xudc_startup_handler - The usb device controller interrupt handler.
1461  * @udc: pointer to the udc structure.
1462  * @intrstatus: The mask value containing the interrupt sources.
1463  *
1464  * This function handles the RESET,SUSPEND,RESUME and DISCONNECT interrupts.
1465  */
1466 static void xudc_startup_handler(struct xusb_udc *udc, u32 intrstatus)
1467 {
1468 	u32 intrreg;
1469 
1470 	if (intrstatus & XUSB_STATUS_RESET_MASK) {
1471 
1472 		dev_dbg(udc->dev, "Reset\n");
1473 
1474 		if (intrstatus & XUSB_STATUS_HIGH_SPEED_MASK)
1475 			udc->gadget.speed = USB_SPEED_HIGH;
1476 		else
1477 			udc->gadget.speed = USB_SPEED_FULL;
1478 
1479 		xudc_stop_activity(udc);
1480 		xudc_clear_stall_all_ep(udc);
1481 		udc->write_fn(udc->addr, XUSB_TESTMODE_OFFSET, 0);
1482 
1483 		/* Set device address and remote wakeup to 0 */
1484 		udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
1485 		udc->remote_wkp = 0;
1486 
1487 		/* Enable the suspend, resume and disconnect */
1488 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1489 		intrreg |= XUSB_STATUS_SUSPEND_MASK | XUSB_STATUS_RESUME_MASK |
1490 			   XUSB_STATUS_DISCONNECT_MASK;
1491 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1492 	}
1493 	if (intrstatus & XUSB_STATUS_SUSPEND_MASK) {
1494 
1495 		dev_dbg(udc->dev, "Suspend\n");
1496 
1497 		/* Enable the reset, resume and disconnect */
1498 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1499 		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_RESUME_MASK |
1500 			   XUSB_STATUS_DISCONNECT_MASK;
1501 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1502 
1503 		udc->usb_state = USB_STATE_SUSPENDED;
1504 
1505 		if (udc->driver->suspend) {
1506 			spin_unlock(&udc->lock);
1507 			udc->driver->suspend(&udc->gadget);
1508 			spin_lock(&udc->lock);
1509 		}
1510 	}
1511 	if (intrstatus & XUSB_STATUS_RESUME_MASK) {
1512 		bool condition = (udc->usb_state != USB_STATE_SUSPENDED);
1513 
1514 		dev_WARN_ONCE(udc->dev, condition,
1515 				"Resume IRQ while not suspended\n");
1516 
1517 		dev_dbg(udc->dev, "Resume\n");
1518 
1519 		/* Enable the reset, suspend and disconnect */
1520 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1521 		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_SUSPEND_MASK |
1522 			   XUSB_STATUS_DISCONNECT_MASK;
1523 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1524 
1525 		udc->usb_state = 0;
1526 
1527 		if (udc->driver->resume) {
1528 			spin_unlock(&udc->lock);
1529 			udc->driver->resume(&udc->gadget);
1530 			spin_lock(&udc->lock);
1531 		}
1532 	}
1533 	if (intrstatus & XUSB_STATUS_DISCONNECT_MASK) {
1534 
1535 		dev_dbg(udc->dev, "Disconnect\n");
1536 
1537 		/* Enable the reset, resume and suspend */
1538 		intrreg = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1539 		intrreg |= XUSB_STATUS_RESET_MASK | XUSB_STATUS_RESUME_MASK |
1540 			   XUSB_STATUS_SUSPEND_MASK;
1541 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, intrreg);
1542 
1543 		if (udc->driver && udc->driver->disconnect) {
1544 			spin_unlock(&udc->lock);
1545 			udc->driver->disconnect(&udc->gadget);
1546 			spin_lock(&udc->lock);
1547 		}
1548 	}
1549 }
1550 
1551 /**
1552  * xudc_ep0_stall - Stall endpoint zero.
1553  * @udc: pointer to the udc structure.
1554  *
1555  * This function stalls endpoint zero.
1556  */
1557 static void xudc_ep0_stall(struct xusb_udc *udc)
1558 {
1559 	u32 epcfgreg;
1560 	struct xusb_ep *ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO];
1561 
1562 	epcfgreg = udc->read_fn(udc->addr + ep0->offset);
1563 	epcfgreg |= XUSB_EP_CFG_STALL_MASK;
1564 	udc->write_fn(udc->addr, ep0->offset, epcfgreg);
1565 }
1566 
1567 /**
1568  * xudc_setaddress - executes SET_ADDRESS command
1569  * @udc: pointer to the udc structure.
1570  *
1571  * This function executes USB SET_ADDRESS command
1572  */
1573 static void xudc_setaddress(struct xusb_udc *udc)
1574 {
1575 	struct xusb_ep *ep0	= &udc->ep[0];
1576 	struct xusb_req *req	= udc->req;
1577 	int ret;
1578 
1579 	req->usb_req.length = 0;
1580 	ret = __xudc_ep0_queue(ep0, req);
1581 	if (ret == 0)
1582 		return;
1583 
1584 	dev_err(udc->dev, "Can't respond to SET ADDRESS request\n");
1585 	xudc_ep0_stall(udc);
1586 }
1587 
1588 /**
1589  * xudc_getstatus - executes GET_STATUS command
1590  * @udc: pointer to the udc structure.
1591  *
1592  * This function executes USB GET_STATUS command
1593  */
1594 static void xudc_getstatus(struct xusb_udc *udc)
1595 {
1596 	struct xusb_ep *ep0	= &udc->ep[0];
1597 	struct xusb_req *req	= udc->req;
1598 	struct xusb_ep *target_ep;
1599 	u16 status = 0;
1600 	u32 epcfgreg;
1601 	int epnum;
1602 	u32 halt;
1603 	int ret;
1604 
1605 	switch (udc->setup.bRequestType & USB_RECIP_MASK) {
1606 	case USB_RECIP_DEVICE:
1607 		/* Get device status */
1608 		status = 1 << USB_DEVICE_SELF_POWERED;
1609 		if (udc->remote_wkp)
1610 			status |= (1 << USB_DEVICE_REMOTE_WAKEUP);
1611 		break;
1612 	case USB_RECIP_INTERFACE:
1613 		break;
1614 	case USB_RECIP_ENDPOINT:
1615 		epnum = udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK;
1616 		target_ep = &udc->ep[epnum];
1617 		epcfgreg = udc->read_fn(udc->addr + target_ep->offset);
1618 		halt = epcfgreg & XUSB_EP_CFG_STALL_MASK;
1619 		if (udc->setup.wIndex & USB_DIR_IN) {
1620 			if (!target_ep->is_in)
1621 				goto stall;
1622 		} else {
1623 			if (target_ep->is_in)
1624 				goto stall;
1625 		}
1626 		if (halt)
1627 			status = 1 << USB_ENDPOINT_HALT;
1628 		break;
1629 	default:
1630 		goto stall;
1631 	}
1632 
1633 	req->usb_req.length = 2;
1634 	*(u16 *)req->usb_req.buf = cpu_to_le16(status);
1635 	ret = __xudc_ep0_queue(ep0, req);
1636 	if (ret == 0)
1637 		return;
1638 stall:
1639 	dev_err(udc->dev, "Can't respond to getstatus request\n");
1640 	xudc_ep0_stall(udc);
1641 }
1642 
1643 /**
1644  * xudc_set_clear_feature - Executes the set feature and clear feature commands.
1645  * @udc: pointer to the usb device controller structure.
1646  *
1647  * Processes the SET_FEATURE and CLEAR_FEATURE commands.
1648  */
1649 static void xudc_set_clear_feature(struct xusb_udc *udc)
1650 {
1651 	struct xusb_ep *ep0	= &udc->ep[0];
1652 	struct xusb_req *req	= udc->req;
1653 	struct xusb_ep *target_ep;
1654 	u8 endpoint;
1655 	u8 outinbit;
1656 	u32 epcfgreg;
1657 	int flag = (udc->setup.bRequest == USB_REQ_SET_FEATURE ? 1 : 0);
1658 	int ret;
1659 
1660 	switch (udc->setup.bRequestType) {
1661 	case USB_RECIP_DEVICE:
1662 		switch (udc->setup.wValue) {
1663 		case USB_DEVICE_TEST_MODE:
1664 			/*
1665 			 * The Test Mode will be executed
1666 			 * after the status phase.
1667 			 */
1668 			break;
1669 		case USB_DEVICE_REMOTE_WAKEUP:
1670 			if (flag)
1671 				udc->remote_wkp = 1;
1672 			else
1673 				udc->remote_wkp = 0;
1674 			break;
1675 		default:
1676 			xudc_ep0_stall(udc);
1677 			break;
1678 		}
1679 		break;
1680 	case USB_RECIP_ENDPOINT:
1681 		if (!udc->setup.wValue) {
1682 			endpoint = udc->setup.wIndex & USB_ENDPOINT_NUMBER_MASK;
1683 			target_ep = &udc->ep[endpoint];
1684 			outinbit = udc->setup.wIndex & USB_ENDPOINT_DIR_MASK;
1685 			outinbit = outinbit >> 7;
1686 
1687 			/* Make sure direction matches.*/
1688 			if (outinbit != target_ep->is_in) {
1689 				xudc_ep0_stall(udc);
1690 				return;
1691 			}
1692 			epcfgreg = udc->read_fn(udc->addr + target_ep->offset);
1693 			if (!endpoint) {
1694 				/* Clear the stall.*/
1695 				epcfgreg &= ~XUSB_EP_CFG_STALL_MASK;
1696 				udc->write_fn(udc->addr,
1697 					      target_ep->offset, epcfgreg);
1698 			} else {
1699 				if (flag) {
1700 					epcfgreg |= XUSB_EP_CFG_STALL_MASK;
1701 					udc->write_fn(udc->addr,
1702 						      target_ep->offset,
1703 						      epcfgreg);
1704 				} else {
1705 					/* Unstall the endpoint.*/
1706 					epcfgreg &= ~(XUSB_EP_CFG_STALL_MASK |
1707 						XUSB_EP_CFG_DATA_TOGGLE_MASK);
1708 					udc->write_fn(udc->addr,
1709 						      target_ep->offset,
1710 						      epcfgreg);
1711 				}
1712 			}
1713 		}
1714 		break;
1715 	default:
1716 		xudc_ep0_stall(udc);
1717 		return;
1718 	}
1719 
1720 	req->usb_req.length = 0;
1721 	ret = __xudc_ep0_queue(ep0, req);
1722 	if (ret == 0)
1723 		return;
1724 
1725 	dev_err(udc->dev, "Can't respond to SET/CLEAR FEATURE\n");
1726 	xudc_ep0_stall(udc);
1727 }
1728 
1729 /**
1730  * xudc_handle_setup - Processes the setup packet.
1731  * @udc: pointer to the usb device controller structure.
1732  *
1733  * Process setup packet and delegate to gadget layer.
1734  */
1735 static void xudc_handle_setup(struct xusb_udc *udc)
1736 {
1737 	struct xusb_ep *ep0 = &udc->ep[0];
1738 	struct usb_ctrlrequest setup;
1739 	u32 *ep0rambase;
1740 
1741 	/* Load up the chapter 9 command buffer.*/
1742 	ep0rambase = (u32 __force *) (udc->addr + XUSB_SETUP_PKT_ADDR_OFFSET);
1743 	memcpy(&setup, ep0rambase, 8);
1744 
1745 	udc->setup = setup;
1746 	udc->setup.wValue = cpu_to_le16(setup.wValue);
1747 	udc->setup.wIndex = cpu_to_le16(setup.wIndex);
1748 	udc->setup.wLength = cpu_to_le16(setup.wLength);
1749 
1750 	/* Clear previous requests */
1751 	xudc_nuke(ep0, -ECONNRESET);
1752 
1753 	if (udc->setup.bRequestType & USB_DIR_IN) {
1754 		/* Execute the get command.*/
1755 		udc->setupseqrx = STATUS_PHASE;
1756 		udc->setupseqtx = DATA_PHASE;
1757 	} else {
1758 		/* Execute the put command.*/
1759 		udc->setupseqrx = DATA_PHASE;
1760 		udc->setupseqtx = STATUS_PHASE;
1761 	}
1762 
1763 	switch (udc->setup.bRequest) {
1764 	case USB_REQ_GET_STATUS:
1765 		/* Data+Status phase form udc */
1766 		if ((udc->setup.bRequestType &
1767 				(USB_DIR_IN | USB_TYPE_MASK)) !=
1768 				(USB_DIR_IN | USB_TYPE_STANDARD))
1769 			break;
1770 		xudc_getstatus(udc);
1771 		return;
1772 	case USB_REQ_SET_ADDRESS:
1773 		/* Status phase from udc */
1774 		if (udc->setup.bRequestType != (USB_DIR_OUT |
1775 				USB_TYPE_STANDARD | USB_RECIP_DEVICE))
1776 			break;
1777 		xudc_setaddress(udc);
1778 		return;
1779 	case USB_REQ_CLEAR_FEATURE:
1780 	case USB_REQ_SET_FEATURE:
1781 		/* Requests with no data phase, status phase from udc */
1782 		if ((udc->setup.bRequestType & USB_TYPE_MASK)
1783 				!= USB_TYPE_STANDARD)
1784 			break;
1785 		xudc_set_clear_feature(udc);
1786 		return;
1787 	default:
1788 		break;
1789 	}
1790 
1791 	spin_unlock(&udc->lock);
1792 	if (udc->driver->setup(&udc->gadget, &setup) < 0)
1793 		xudc_ep0_stall(udc);
1794 	spin_lock(&udc->lock);
1795 }
1796 
1797 /**
1798  * xudc_ep0_out - Processes the endpoint 0 OUT token.
1799  * @udc: pointer to the usb device controller structure.
1800  */
1801 static void xudc_ep0_out(struct xusb_udc *udc)
1802 {
1803 	struct xusb_ep *ep0 = &udc->ep[0];
1804 	struct xusb_req *req;
1805 	u8 *ep0rambase;
1806 	unsigned int bytes_to_rx;
1807 	void *buffer;
1808 
1809 	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
1810 
1811 	switch (udc->setupseqrx) {
1812 	case STATUS_PHASE:
1813 		/*
1814 		 * This resets both state machines for the next
1815 		 * Setup packet.
1816 		 */
1817 		udc->setupseqrx = SETUP_PHASE;
1818 		udc->setupseqtx = SETUP_PHASE;
1819 		req->usb_req.actual = req->usb_req.length;
1820 		xudc_done(ep0, req, 0);
1821 		break;
1822 	case DATA_PHASE:
1823 		bytes_to_rx = udc->read_fn(udc->addr +
1824 					   XUSB_EP_BUF0COUNT_OFFSET);
1825 		/* Copy the data to be received from the DPRAM. */
1826 		ep0rambase = (u8 __force *) (udc->addr +
1827 			     (ep0->rambase << 2));
1828 		buffer = req->usb_req.buf + req->usb_req.actual;
1829 		req->usb_req.actual = req->usb_req.actual + bytes_to_rx;
1830 		memcpy(buffer, ep0rambase, bytes_to_rx);
1831 
1832 		if (req->usb_req.length == req->usb_req.actual) {
1833 			/* Data transfer completed get ready for Status stage */
1834 			xudc_wrstatus(udc);
1835 		} else {
1836 			/* Enable EP0 buffer to receive data */
1837 			udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, 0);
1838 			udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1839 		}
1840 		break;
1841 	default:
1842 		break;
1843 	}
1844 }
1845 
1846 /**
1847  * xudc_ep0_in - Processes the endpoint 0 IN token.
1848  * @udc: pointer to the usb device controller structure.
1849  */
1850 static void xudc_ep0_in(struct xusb_udc *udc)
1851 {
1852 	struct xusb_ep *ep0 = &udc->ep[0];
1853 	struct xusb_req *req;
1854 	unsigned int bytes_to_tx;
1855 	void *buffer;
1856 	u32 epcfgreg;
1857 	u16 count = 0;
1858 	u16 length;
1859 	u8 *ep0rambase;
1860 	u8 test_mode = udc->setup.wIndex >> 8;
1861 
1862 	req = list_first_entry(&ep0->queue, struct xusb_req, queue);
1863 	bytes_to_tx = req->usb_req.length - req->usb_req.actual;
1864 
1865 	switch (udc->setupseqtx) {
1866 	case STATUS_PHASE:
1867 		switch (udc->setup.bRequest) {
1868 		case USB_REQ_SET_ADDRESS:
1869 			/* Set the address of the device.*/
1870 			udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET,
1871 				      udc->setup.wValue);
1872 			break;
1873 		case USB_REQ_SET_FEATURE:
1874 			if (udc->setup.bRequestType ==
1875 					USB_RECIP_DEVICE) {
1876 				if (udc->setup.wValue ==
1877 						USB_DEVICE_TEST_MODE)
1878 					udc->write_fn(udc->addr,
1879 						      XUSB_TESTMODE_OFFSET,
1880 						      test_mode);
1881 			}
1882 			break;
1883 		}
1884 		req->usb_req.actual = req->usb_req.length;
1885 		xudc_done(ep0, req, 0);
1886 		break;
1887 	case DATA_PHASE:
1888 		if (!bytes_to_tx) {
1889 			/*
1890 			 * We're done with data transfer, next
1891 			 * will be zero length OUT with data toggle of
1892 			 * 1. Setup data_toggle.
1893 			 */
1894 			epcfgreg = udc->read_fn(udc->addr + ep0->offset);
1895 			epcfgreg |= XUSB_EP_CFG_DATA_TOGGLE_MASK;
1896 			udc->write_fn(udc->addr, ep0->offset, epcfgreg);
1897 			udc->setupseqtx = STATUS_PHASE;
1898 		} else {
1899 			length = count = min_t(u32, bytes_to_tx,
1900 					       EP0_MAX_PACKET);
1901 			/* Copy the data to be transmitted into the DPRAM. */
1902 			ep0rambase = (u8 __force *) (udc->addr +
1903 				     (ep0->rambase << 2));
1904 			buffer = req->usb_req.buf + req->usb_req.actual;
1905 			req->usb_req.actual = req->usb_req.actual + length;
1906 			memcpy(ep0rambase, buffer, length);
1907 		}
1908 		udc->write_fn(udc->addr, XUSB_EP_BUF0COUNT_OFFSET, count);
1909 		udc->write_fn(udc->addr, XUSB_BUFFREADY_OFFSET, 1);
1910 		break;
1911 	default:
1912 		break;
1913 	}
1914 }
1915 
1916 /**
1917  * xudc_ctrl_ep_handler - Endpoint 0 interrupt handler.
1918  * @udc: pointer to the udc structure.
1919  * @intrstatus:	It's the mask value for the interrupt sources on endpoint 0.
1920  *
1921  * Processes the commands received during enumeration phase.
1922  */
1923 static void xudc_ctrl_ep_handler(struct xusb_udc *udc, u32 intrstatus)
1924 {
1925 
1926 	if (intrstatus & XUSB_STATUS_SETUP_PACKET_MASK) {
1927 		xudc_handle_setup(udc);
1928 	} else {
1929 		if (intrstatus & XUSB_STATUS_FIFO_BUFF_RDY_MASK)
1930 			xudc_ep0_out(udc);
1931 		else if (intrstatus & XUSB_STATUS_FIFO_BUFF_FREE_MASK)
1932 			xudc_ep0_in(udc);
1933 	}
1934 }
1935 
1936 /**
1937  * xudc_nonctrl_ep_handler - Non control endpoint interrupt handler.
1938  * @udc: pointer to the udc structure.
1939  * @epnum: End point number for which the interrupt is to be processed
1940  * @intrstatus:	mask value for interrupt sources of endpoints other
1941  *		than endpoint 0.
1942  *
1943  * Processes the buffer completion interrupts.
1944  */
1945 static void xudc_nonctrl_ep_handler(struct xusb_udc *udc, u8 epnum,
1946 				    u32 intrstatus)
1947 {
1948 
1949 	struct xusb_req *req;
1950 	struct xusb_ep *ep;
1951 
1952 	ep = &udc->ep[epnum];
1953 	/* Process the End point interrupts.*/
1954 	if (intrstatus & (XUSB_STATUS_EP0_BUFF1_COMP_MASK << epnum))
1955 		ep->buffer0ready = 0;
1956 	if (intrstatus & (XUSB_STATUS_EP0_BUFF2_COMP_MASK << epnum))
1957 		ep->buffer1ready = 0;
1958 
1959 	if (list_empty(&ep->queue))
1960 		return;
1961 
1962 	req = list_first_entry(&ep->queue, struct xusb_req, queue);
1963 
1964 	if (ep->is_in)
1965 		xudc_write_fifo(ep, req);
1966 	else
1967 		xudc_read_fifo(ep, req);
1968 }
1969 
1970 /**
1971  * xudc_irq - The main interrupt handler.
1972  * @irq: The interrupt number.
1973  * @_udc: pointer to the usb device controller structure.
1974  *
1975  * Return: IRQ_HANDLED after the interrupt is handled.
1976  */
1977 static irqreturn_t xudc_irq(int irq, void *_udc)
1978 {
1979 	struct xusb_udc *udc = _udc;
1980 	u32 intrstatus;
1981 	u32 ier;
1982 	u8 index;
1983 	u32 bufintr;
1984 	unsigned long flags;
1985 
1986 	spin_lock_irqsave(&udc->lock, flags);
1987 
1988 	/*
1989 	 * Event interrupts are level sensitive hence first disable
1990 	 * IER, read ISR and figure out active interrupts.
1991 	 */
1992 	ier = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
1993 	ier &= ~XUSB_STATUS_INTR_EVENT_MASK;
1994 	udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
1995 
1996 	/* Read the Interrupt Status Register.*/
1997 	intrstatus = udc->read_fn(udc->addr + XUSB_STATUS_OFFSET);
1998 
1999 	/* Call the handler for the event interrupt.*/
2000 	if (intrstatus & XUSB_STATUS_INTR_EVENT_MASK) {
2001 		/*
2002 		 * Check if there is any action to be done for :
2003 		 * - USB Reset received {XUSB_STATUS_RESET_MASK}
2004 		 * - USB Suspend received {XUSB_STATUS_SUSPEND_MASK}
2005 		 * - USB Resume received {XUSB_STATUS_RESUME_MASK}
2006 		 * - USB Disconnect received {XUSB_STATUS_DISCONNECT_MASK}
2007 		 */
2008 		xudc_startup_handler(udc, intrstatus);
2009 	}
2010 
2011 	/* Check the buffer completion interrupts */
2012 	if (intrstatus & XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK) {
2013 		/* Enable Reset, Suspend, Resume and Disconnect  */
2014 		ier = udc->read_fn(udc->addr + XUSB_IER_OFFSET);
2015 		ier |= XUSB_STATUS_INTR_EVENT_MASK;
2016 		udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
2017 
2018 		if (intrstatus & XUSB_STATUS_EP0_BUFF1_COMP_MASK)
2019 			xudc_ctrl_ep_handler(udc, intrstatus);
2020 
2021 		for (index = 1; index < 8; index++) {
2022 			bufintr = ((intrstatus &
2023 				  (XUSB_STATUS_EP1_BUFF1_COMP_MASK <<
2024 				  (index - 1))) || (intrstatus &
2025 				  (XUSB_STATUS_EP1_BUFF2_COMP_MASK <<
2026 				  (index - 1))));
2027 			if (bufintr) {
2028 				xudc_nonctrl_ep_handler(udc, index,
2029 							intrstatus);
2030 			}
2031 		}
2032 	}
2033 
2034 	spin_unlock_irqrestore(&udc->lock, flags);
2035 	return IRQ_HANDLED;
2036 }
2037 
2038 /**
2039  * xudc_probe - The device probe function for driver initialization.
2040  * @pdev: pointer to the platform device structure.
2041  *
2042  * Return: 0 for success and error value on failure
2043  */
2044 static int xudc_probe(struct platform_device *pdev)
2045 {
2046 	struct device_node *np = pdev->dev.of_node;
2047 	struct resource *res;
2048 	struct xusb_udc *udc;
2049 	struct xusb_ep *ep0;
2050 	int irq;
2051 	int ret;
2052 	u32 ier;
2053 	u8 *buff;
2054 
2055 	udc = devm_kzalloc(&pdev->dev, sizeof(*udc), GFP_KERNEL);
2056 	if (!udc)
2057 		return -ENOMEM;
2058 
2059 	/* Create a dummy request for GET_STATUS, SET_ADDRESS */
2060 	udc->req = devm_kzalloc(&pdev->dev, sizeof(struct xusb_req),
2061 				GFP_KERNEL);
2062 	if (!udc->req)
2063 		return -ENOMEM;
2064 
2065 	buff = devm_kzalloc(&pdev->dev, STATUSBUFF_SIZE, GFP_KERNEL);
2066 	if (!buff)
2067 		return -ENOMEM;
2068 
2069 	udc->req->usb_req.buf = buff;
2070 
2071 	/* Map the registers */
2072 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
2073 	udc->addr = devm_ioremap_resource(&pdev->dev, res);
2074 	if (!udc->addr)
2075 		return -ENOMEM;
2076 
2077 	irq = platform_get_irq(pdev, 0);
2078 	if (irq < 0) {
2079 		dev_err(&pdev->dev, "unable to get irq\n");
2080 		return irq;
2081 	}
2082 	ret = devm_request_irq(&pdev->dev, irq, xudc_irq, 0,
2083 			       dev_name(&pdev->dev), udc);
2084 	if (ret < 0) {
2085 		dev_dbg(&pdev->dev, "unable to request irq %d", irq);
2086 		goto fail;
2087 	}
2088 
2089 	udc->dma_enabled = of_property_read_bool(np, "xlnx,has-builtin-dma");
2090 
2091 	/* Setup gadget structure */
2092 	udc->gadget.ops = &xusb_udc_ops;
2093 	udc->gadget.max_speed = USB_SPEED_HIGH;
2094 	udc->gadget.speed = USB_SPEED_UNKNOWN;
2095 	udc->gadget.ep0 = &udc->ep[XUSB_EP_NUMBER_ZERO].ep_usb;
2096 	udc->gadget.name = driver_name;
2097 
2098 	spin_lock_init(&udc->lock);
2099 
2100 	/* Check for IP endianness */
2101 	udc->write_fn = xudc_write32_be;
2102 	udc->read_fn = xudc_read32_be;
2103 	udc->write_fn(udc->addr, XUSB_TESTMODE_OFFSET, TEST_J);
2104 	if ((udc->read_fn(udc->addr + XUSB_TESTMODE_OFFSET))
2105 			!= TEST_J) {
2106 		udc->write_fn = xudc_write32;
2107 		udc->read_fn = xudc_read32;
2108 	}
2109 	udc->write_fn(udc->addr, XUSB_TESTMODE_OFFSET, 0);
2110 
2111 	xudc_eps_init(udc);
2112 
2113 	ep0 = &udc->ep[0];
2114 
2115 	/* Set device address to 0.*/
2116 	udc->write_fn(udc->addr, XUSB_ADDRESS_OFFSET, 0);
2117 
2118 	ret = usb_add_gadget_udc(&pdev->dev, &udc->gadget);
2119 	if (ret)
2120 		goto fail;
2121 
2122 	udc->dev = &udc->gadget.dev;
2123 
2124 	/* Enable the interrupts.*/
2125 	ier = XUSB_STATUS_GLOBAL_INTR_MASK | XUSB_STATUS_INTR_EVENT_MASK |
2126 	      XUSB_STATUS_FIFO_BUFF_RDY_MASK | XUSB_STATUS_FIFO_BUFF_FREE_MASK |
2127 	      XUSB_STATUS_SETUP_PACKET_MASK |
2128 	      XUSB_STATUS_INTR_BUFF_COMP_ALL_MASK;
2129 
2130 	udc->write_fn(udc->addr, XUSB_IER_OFFSET, ier);
2131 
2132 	platform_set_drvdata(pdev, udc);
2133 
2134 	dev_vdbg(&pdev->dev, "%s at 0x%08X mapped to %p %s\n",
2135 		 driver_name, (u32)res->start, udc->addr,
2136 		 udc->dma_enabled ? "with DMA" : "without DMA");
2137 
2138 	return 0;
2139 fail:
2140 	dev_err(&pdev->dev, "probe failed, %d\n", ret);
2141 	return ret;
2142 }
2143 
2144 /**
2145  * xudc_remove - Releases the resources allocated during the initialization.
2146  * @pdev: pointer to the platform device structure.
2147  *
2148  * Return: 0 always
2149  */
2150 static int xudc_remove(struct platform_device *pdev)
2151 {
2152 	struct xusb_udc *udc = platform_get_drvdata(pdev);
2153 
2154 	usb_del_gadget_udc(&udc->gadget);
2155 
2156 	return 0;
2157 }
2158 
2159 /* Match table for of_platform binding */
2160 static const struct of_device_id usb_of_match[] = {
2161 	{ .compatible = "xlnx,usb2-device-4.00.a", },
2162 	{ /* end of list */ },
2163 };
2164 MODULE_DEVICE_TABLE(of, usb_of_match);
2165 
2166 static struct platform_driver xudc_driver = {
2167 	.driver = {
2168 		.name = driver_name,
2169 		.of_match_table = usb_of_match,
2170 	},
2171 	.probe = xudc_probe,
2172 	.remove = xudc_remove,
2173 };
2174 
2175 module_platform_driver(xudc_driver);
2176 
2177 MODULE_DESCRIPTION("Xilinx udc driver");
2178 MODULE_AUTHOR("Xilinx, Inc");
2179 MODULE_LICENSE("GPL");
2180