xref: /openbmc/linux/drivers/usb/gadget/udc/net2272.h (revision 3213486f)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * PLX NET2272 high/full speed USB device controller
4  *
5  * Copyright (C) 2005-2006 PLX Technology, Inc.
6  * Copyright (C) 2006-2011 Analog Devices, Inc.
7  */
8 
9 #ifndef __NET2272_H__
10 #define __NET2272_H__
11 
12 /* Main Registers */
13 #define REGADDRPTR			0x00
14 #define REGDATA				0x01
15 #define IRQSTAT0			0x02
16 #define 	ENDPOINT_0_INTERRUPT			0
17 #define 	ENDPOINT_A_INTERRUPT			1
18 #define 	ENDPOINT_B_INTERRUPT			2
19 #define 	ENDPOINT_C_INTERRUPT			3
20 #define 	VIRTUALIZED_ENDPOINT_INTERRUPT		4
21 #define 	SETUP_PACKET_INTERRUPT			5
22 #define 	DMA_DONE_INTERRUPT			6
23 #define 	SOF_INTERRUPT				7
24 #define IRQSTAT1			0x03
25 #define 	CONTROL_STATUS_INTERRUPT		1
26 #define 	VBUS_INTERRUPT				2
27 #define 	SUSPEND_REQUEST_INTERRUPT		3
28 #define 	SUSPEND_REQUEST_CHANGE_INTERRUPT	4
29 #define 	RESUME_INTERRUPT			5
30 #define 	ROOT_PORT_RESET_INTERRUPT		6
31 #define 	RESET_STATUS				7
32 #define PAGESEL				0x04
33 #define DMAREQ				0x1c
34 #define 	DMA_ENDPOINT_SELECT			0
35 #define 	DREQ_POLARITY				1
36 #define 	DACK_POLARITY				2
37 #define 	EOT_POLARITY				3
38 #define 	DMA_CONTROL_DACK			4
39 #define 	DMA_REQUEST_ENABLE			5
40 #define 	DMA_REQUEST				6
41 #define 	DMA_BUFFER_VALID			7
42 #define SCRATCH				0x1d
43 #define IRQENB0				0x20
44 #define 	ENDPOINT_0_INTERRUPT_ENABLE		0
45 #define 	ENDPOINT_A_INTERRUPT_ENABLE		1
46 #define 	ENDPOINT_B_INTERRUPT_ENABLE		2
47 #define 	ENDPOINT_C_INTERRUPT_ENABLE		3
48 #define 	VIRTUALIZED_ENDPOINT_INTERRUPT_ENABLE	4
49 #define 	SETUP_PACKET_INTERRUPT_ENABLE		5
50 #define 	DMA_DONE_INTERRUPT_ENABLE		6
51 #define 	SOF_INTERRUPT_ENABLE			7
52 #define IRQENB1				0x21
53 #define 	VBUS_INTERRUPT_ENABLE			2
54 #define 	SUSPEND_REQUEST_INTERRUPT_ENABLE	3
55 #define 	SUSPEND_REQUEST_CHANGE_INTERRUPT_ENABLE	4
56 #define 	RESUME_INTERRUPT_ENABLE			5
57 #define 	ROOT_PORT_RESET_INTERRUPT_ENABLE	6
58 #define LOCCTL				0x22
59 #define 	DATA_WIDTH				0
60 #define 	LOCAL_CLOCK_OUTPUT			1
61 #define 		LOCAL_CLOCK_OUTPUT_OFF			0
62 #define 		LOCAL_CLOCK_OUTPUT_3_75MHZ		1
63 #define 		LOCAL_CLOCK_OUTPUT_7_5MHZ		2
64 #define 		LOCAL_CLOCK_OUTPUT_15MHZ		3
65 #define 		LOCAL_CLOCK_OUTPUT_30MHZ		4
66 #define 		LOCAL_CLOCK_OUTPUT_60MHZ		5
67 #define 	DMA_SPLIT_BUS_MODE			4
68 #define 	BYTE_SWAP				5
69 #define 	BUFFER_CONFIGURATION			6
70 #define 		BUFFER_CONFIGURATION_EPA512_EPB512	0
71 #define 		BUFFER_CONFIGURATION_EPA1024_EPB512	1
72 #define 		BUFFER_CONFIGURATION_EPA1024_EPB1024	2
73 #define 		BUFFER_CONFIGURATION_EPA1024DB		3
74 #define CHIPREV_LEGACY			0x23
75 #define 		NET2270_LEGACY_REV			0x40
76 #define LOCCTL1				0x24
77 #define 	DMA_MODE				0
78 #define 		SLOW_DREQ				0
79 #define 		FAST_DREQ				1
80 #define 		BURST_MODE				2
81 #define 	DMA_DACK_ENABLE				2
82 #define CHIPREV_2272			0x25
83 #define 		CHIPREV_NET2272_R1			0x10
84 #define 		CHIPREV_NET2272_R1A			0x11
85 /* USB Registers */
86 #define USBCTL0				0x18
87 #define 	IO_WAKEUP_ENABLE			1
88 #define 	USB_DETECT_ENABLE			3
89 #define 	USB_ROOT_PORT_WAKEUP_ENABLE		5
90 #define USBCTL1				0x19
91 #define 	VBUS_PIN				0
92 #define 		USB_FULL_SPEED				1
93 #define 		USB_HIGH_SPEED				2
94 #define 	GENERATE_RESUME				3
95 #define 	VIRTUAL_ENDPOINT_ENABLE			4
96 #define FRAME0				0x1a
97 #define FRAME1				0x1b
98 #define OURADDR				0x30
99 #define 	FORCE_IMMEDIATE				7
100 #define USBDIAG				0x31
101 #define 	FORCE_TRANSMIT_CRC_ERROR		0
102 #define 	PREVENT_TRANSMIT_BIT_STUFF		1
103 #define 	FORCE_RECEIVE_ERROR			2
104 #define 	FAST_TIMES				4
105 #define USBTEST				0x32
106 #define 	TEST_MODE_SELECT			0
107 #define 		NORMAL_OPERATION			0
108 #define 		TEST_J					1
109 #define 		TEST_K					2
110 #define 		TEST_SE0_NAK				3
111 #define 		TEST_PACKET				4
112 #define 		TEST_FORCE_ENABLE			5
113 #define XCVRDIAG			0x33
114 #define 	FORCE_FULL_SPEED			2
115 #define 	FORCE_HIGH_SPEED			3
116 #define 	OPMODE					4
117 #define 		NORMAL_OPERATION			0
118 #define 		NON_DRIVING				1
119 #define 		DISABLE_BITSTUFF_AND_NRZI_ENCODE	2
120 #define 	LINESTATE				6
121 #define 		SE0_STATE				0
122 #define 		J_STATE					1
123 #define 		K_STATE					2
124 #define 		SE1_STATE				3
125 #define VIRTOUT0			0x34
126 #define VIRTOUT1			0x35
127 #define VIRTIN0				0x36
128 #define VIRTIN1				0x37
129 #define SETUP0				0x40
130 #define SETUP1				0x41
131 #define SETUP2				0x42
132 #define SETUP3				0x43
133 #define SETUP4				0x44
134 #define SETUP5				0x45
135 #define SETUP6				0x46
136 #define SETUP7				0x47
137 /* Endpoint Registers (Paged via PAGESEL) */
138 #define EP_DATA				0x05
139 #define EP_STAT0			0x06
140 #define 	DATA_IN_TOKEN_INTERRUPT			0
141 #define 	DATA_OUT_TOKEN_INTERRUPT		1
142 #define 	DATA_PACKET_TRANSMITTED_INTERRUPT	2
143 #define 	DATA_PACKET_RECEIVED_INTERRUPT		3
144 #define 	SHORT_PACKET_TRANSFERRED_INTERRUPT	4
145 #define 	NAK_OUT_PACKETS				5
146 #define 	BUFFER_EMPTY				6
147 #define 	BUFFER_FULL				7
148 #define EP_STAT1			0x07
149 #define 	TIMEOUT					0
150 #define 	USB_OUT_ACK_SENT			1
151 #define 	USB_OUT_NAK_SENT			2
152 #define 	USB_IN_ACK_RCVD				3
153 #define 	USB_IN_NAK_SENT				4
154 #define 	USB_STALL_SENT				5
155 #define 	LOCAL_OUT_ZLP				6
156 #define 	BUFFER_FLUSH				7
157 #define EP_TRANSFER0			0x08
158 #define EP_TRANSFER1			0x09
159 #define EP_TRANSFER2			0x0a
160 #define EP_IRQENB			0x0b
161 #define 	DATA_IN_TOKEN_INTERRUPT_ENABLE		0
162 #define 	DATA_OUT_TOKEN_INTERRUPT_ENABLE		1
163 #define 	DATA_PACKET_TRANSMITTED_INTERRUPT_ENABLE	2
164 #define 	DATA_PACKET_RECEIVED_INTERRUPT_ENABLE	3
165 #define 	SHORT_PACKET_TRANSFERRED_INTERRUPT_ENABLE	4
166 #define EP_AVAIL0			0x0c
167 #define EP_AVAIL1			0x0d
168 #define EP_RSPCLR			0x0e
169 #define EP_RSPSET			0x0f
170 #define 	ENDPOINT_HALT				0
171 #define 	ENDPOINT_TOGGLE				1
172 #define 	NAK_OUT_PACKETS_MODE			2
173 #define 	CONTROL_STATUS_PHASE_HANDSHAKE		3
174 #define 	INTERRUPT_MODE				4
175 #define 	AUTOVALIDATE				5
176 #define 	HIDE_STATUS_PHASE			6
177 #define 	ALT_NAK_OUT_PACKETS			7
178 #define EP_MAXPKT0			0x28
179 #define EP_MAXPKT1			0x29
180 #define 	ADDITIONAL_TRANSACTION_OPPORTUNITIES	3
181 #define 		NONE_ADDITIONAL_TRANSACTION		0
182 #define 		ONE_ADDITIONAL_TRANSACTION		1
183 #define 		TWO_ADDITIONAL_TRANSACTION		2
184 #define EP_CFG				0x2a
185 #define 	ENDPOINT_NUMBER				0
186 #define 	ENDPOINT_DIRECTION			4
187 #define 	ENDPOINT_TYPE				5
188 #define 	ENDPOINT_ENABLE				7
189 #define EP_HBW				0x2b
190 #define 	HIGH_BANDWIDTH_OUT_TRANSACTION_PID	0
191 #define 		DATA0_PID				0
192 #define 		DATA1_PID				1
193 #define 		DATA2_PID				2
194 #define 		MDATA_PID				3
195 #define EP_BUFF_STATES			0x2c
196 #define 	BUFFER_A_STATE				0
197 #define 	BUFFER_B_STATE				2
198 #define 		BUFF_FREE				0
199 #define 		BUFF_VALID				1
200 #define 		BUFF_LCL				2
201 #define 		BUFF_USB				3
202 
203 /*---------------------------------------------------------------------------*/
204 
205 #define PCI_DEVICE_ID_RDK1	0x9054
206 
207 /* PCI-RDK EPLD Registers */
208 #define RDK_EPLD_IO_REGISTER1		0x00000000
209 #define 	RDK_EPLD_USB_RESET				0
210 #define 	RDK_EPLD_USB_POWERDOWN				1
211 #define 	RDK_EPLD_USB_WAKEUP				2
212 #define 	RDK_EPLD_USB_EOT				3
213 #define 	RDK_EPLD_DPPULL					4
214 #define RDK_EPLD_IO_REGISTER2		0x00000004
215 #define 	RDK_EPLD_BUSWIDTH				0
216 #define 	RDK_EPLD_USER					2
217 #define 	RDK_EPLD_RESET_INTERRUPT_ENABLE			3
218 #define 	RDK_EPLD_DMA_TIMEOUT_ENABLE			4
219 #define RDK_EPLD_STATUS_REGISTER	0x00000008
220 #define 	RDK_EPLD_USB_LRESET				0
221 #define RDK_EPLD_REVISION_REGISTER	0x0000000c
222 
223 /* PCI-RDK PLX 9054 Registers */
224 #define INTCSR				0x68
225 #define 	PCI_INTERRUPT_ENABLE				8
226 #define 	LOCAL_INTERRUPT_INPUT_ENABLE			11
227 #define 	LOCAL_INPUT_INTERRUPT_ACTIVE			15
228 #define 	LOCAL_DMA_CHANNEL_0_INTERRUPT_ENABLE		18
229 #define 	LOCAL_DMA_CHANNEL_1_INTERRUPT_ENABLE		19
230 #define 	DMA_CHANNEL_0_INTERRUPT_ACTIVE			21
231 #define 	DMA_CHANNEL_1_INTERRUPT_ACTIVE			22
232 #define CNTRL				0x6C
233 #define 	RELOAD_CONFIGURATION_REGISTERS			29
234 #define 	PCI_ADAPTER_SOFTWARE_RESET			30
235 #define DMAMODE0			0x80
236 #define 	LOCAL_BUS_WIDTH					0
237 #define 	INTERNAL_WAIT_STATES				2
238 #define 	TA_READY_INPUT_ENABLE				6
239 #define 	LOCAL_BURST_ENABLE				8
240 #define 	SCATTER_GATHER_MODE				9
241 #define 	DONE_INTERRUPT_ENABLE				10
242 #define 	LOCAL_ADDRESSING_MODE				11
243 #define 	DEMAND_MODE					12
244 #define 	DMA_EOT_ENABLE					14
245 #define 	FAST_SLOW_TERMINATE_MODE_SELECT			15
246 #define 	DMA_CHANNEL_INTERRUPT_SELECT			17
247 #define DMAPADR0			0x84
248 #define DMALADR0			0x88
249 #define DMASIZ0				0x8c
250 #define DMADPR0				0x90
251 #define 	DESCRIPTOR_LOCATION				0
252 #define 	END_OF_CHAIN					1
253 #define 	INTERRUPT_AFTER_TERMINAL_COUNT			2
254 #define 	DIRECTION_OF_TRANSFER				3
255 #define DMACSR0				0xa8
256 #define 	CHANNEL_ENABLE					0
257 #define 	CHANNEL_START					1
258 #define 	CHANNEL_ABORT					2
259 #define 	CHANNEL_CLEAR_INTERRUPT				3
260 #define 	CHANNEL_DONE					4
261 #define DMATHR				0xb0
262 #define LBRD1				0xf8
263 #define 	MEMORY_SPACE_LOCAL_BUS_WIDTH			0
264 #define 	W8_BIT						0
265 #define 	W16_BIT						1
266 
267 /* Special OR'ing of INTCSR bits */
268 #define LOCAL_INTERRUPT_TEST \
269 	((1 << LOCAL_INPUT_INTERRUPT_ACTIVE) | \
270 	 (1 << LOCAL_INTERRUPT_INPUT_ENABLE))
271 
272 #define DMA_CHANNEL_0_TEST \
273 	((1 << DMA_CHANNEL_0_INTERRUPT_ACTIVE) | \
274 	 (1 << LOCAL_DMA_CHANNEL_0_INTERRUPT_ENABLE))
275 
276 #define DMA_CHANNEL_1_TEST \
277 	((1 << DMA_CHANNEL_1_INTERRUPT_ACTIVE) | \
278 	 (1 << LOCAL_DMA_CHANNEL_1_INTERRUPT_ENABLE))
279 
280 /* EPLD Registers */
281 #define RDK_EPLD_IO_REGISTER1			0x00000000
282 #define 	RDK_EPLD_USB_RESET			0
283 #define 	RDK_EPLD_USB_POWERDOWN			1
284 #define 	RDK_EPLD_USB_WAKEUP			2
285 #define 	RDK_EPLD_USB_EOT			3
286 #define 	RDK_EPLD_DPPULL				4
287 #define RDK_EPLD_IO_REGISTER2			0x00000004
288 #define 	RDK_EPLD_BUSWIDTH			0
289 #define 	RDK_EPLD_USER				2
290 #define 	RDK_EPLD_RESET_INTERRUPT_ENABLE		3
291 #define 	RDK_EPLD_DMA_TIMEOUT_ENABLE		4
292 #define RDK_EPLD_STATUS_REGISTER		0x00000008
293 #define RDK_EPLD_USB_LRESET				0
294 #define RDK_EPLD_REVISION_REGISTER		0x0000000c
295 
296 #define EPLD_IO_CONTROL_REGISTER		0x400
297 #define 	NET2272_RESET				0
298 #define 	BUSWIDTH				1
299 #define 	MPX_MODE				3
300 #define 	USER					4
301 #define 	DMA_TIMEOUT_ENABLE			5
302 #define 	DMA_CTL_DACK				6
303 #define 	EPLD_DMA_ENABLE				7
304 #define EPLD_DMA_CONTROL_REGISTER		0x800
305 #define 	SPLIT_DMA_MODE				0
306 #define 	SPLIT_DMA_DIRECTION			1
307 #define 	SPLIT_DMA_ENABLE			2
308 #define 	SPLIT_DMA_INTERRUPT_ENABLE		3
309 #define 	SPLIT_DMA_INTERRUPT			4
310 #define 	EPLD_DMA_MODE				5
311 #define 	EPLD_DMA_CONTROLLER_ENABLE		7
312 #define SPLIT_DMA_ADDRESS_LOW			0xc00
313 #define SPLIT_DMA_ADDRESS_HIGH			0x1000
314 #define SPLIT_DMA_BYTE_COUNT_LOW		0x1400
315 #define SPLIT_DMA_BYTE_COUNT_HIGH		0x1800
316 #define EPLD_REVISION_REGISTER			0x1c00
317 #define SPLIT_DMA_RAM				0x4000
318 #define DMA_RAM_SIZE				0x1000
319 
320 /*---------------------------------------------------------------------------*/
321 
322 #define PCI_DEVICE_ID_RDK2	0x3272
323 
324 /* PCI-RDK version 2 registers */
325 
326 /* Main Control Registers */
327 
328 #define RDK2_IRQENB			0x00
329 #define RDK2_IRQSTAT			0x04
330 #define 	PB7				23
331 #define 	PB6				22
332 #define 	PB5				21
333 #define 	PB4				20
334 #define 	PB3				19
335 #define 	PB2				18
336 #define 	PB1				17
337 #define 	PB0				16
338 #define 	GP3				23
339 #define 	GP2				23
340 #define 	GP1				23
341 #define 	GP0				23
342 #define 	DMA_RETRY_ABORT			6
343 #define 	DMA_PAUSE_DONE			5
344 #define 	DMA_ABORT_DONE			4
345 #define 	DMA_OUT_FIFO_TRANSFER_DONE	3
346 #define 	DMA_LOCAL_DONE			2
347 #define 	DMA_PCI_DONE			1
348 #define 	NET2272_PCI_IRQ			0
349 
350 #define RDK2_LOCCTLRDK			0x08
351 #define 	CHIP_RESET			3
352 #define 	SPLIT_DMA			2
353 #define 	MULTIPLEX_MODE			1
354 #define 	BUS_WIDTH			0
355 
356 #define RDK2_GPIOCTL			0x10
357 #define 	GP3_OUT_ENABLE					7
358 #define 	GP2_OUT_ENABLE					6
359 #define 	GP1_OUT_ENABLE					5
360 #define 	GP0_OUT_ENABLE					4
361 #define 	GP3_DATA					3
362 #define 	GP2_DATA					2
363 #define 	GP1_DATA					1
364 #define 	GP0_DATA					0
365 
366 #define RDK2_LEDSW			0x14
367 #define 	LED3				27
368 #define 	LED2				26
369 #define 	LED1				25
370 #define 	LED0				24
371 #define 	PBUTTON				16
372 #define 	DIPSW				0
373 
374 #define RDK2_DIAG			0x18
375 #define 	RDK2_FAST_TIMES				2
376 #define 	FORCE_PCI_SERR				1
377 #define 	FORCE_PCI_INT				0
378 #define RDK2_FPGAREV			0x1C
379 
380 /* Dma Control registers */
381 #define RDK2_DMACTL			0x80
382 #define 	ADDR_HOLD				24
383 #define 	RETRY_COUNT				16	/* 23:16 */
384 #define 	FIFO_THRESHOLD				11	/* 15:11 */
385 #define 	MEM_WRITE_INVALIDATE			10
386 #define 	READ_MULTIPLE				9
387 #define 	READ_LINE				8
388 #define 	RDK2_DMA_MODE				6	/* 7:6 */
389 #define 	CONTROL_DACK				5
390 #define 	EOT_ENABLE				4
391 #define 	EOT_POLARITY				3
392 #define 	DACK_POLARITY				2
393 #define 	DREQ_POLARITY				1
394 #define 	DMA_ENABLE				0
395 
396 #define RDK2_DMASTAT			0x84
397 #define 	GATHER_COUNT				12	/* 14:12 */
398 #define 	FIFO_COUNT				6	/* 11:6 */
399 #define 	FIFO_FLUSH				5
400 #define 	FIFO_TRANSFER				4
401 #define 	PAUSE_DONE				3
402 #define 	ABORT_DONE				2
403 #define 	DMA_ABORT				1
404 #define 	DMA_START				0
405 
406 #define RDK2_DMAPCICOUNT		0x88
407 #define 	DMA_DIRECTION				31
408 #define 	DMA_PCI_BYTE_COUNT			0	/* 0:23 */
409 
410 #define RDK2_DMALOCCOUNT		0x8C	/* 0:23 dma local byte count */
411 
412 #define RDK2_DMAADDR			0x90	/* 2:31 PCI bus starting address */
413 
414 /*---------------------------------------------------------------------------*/
415 
416 #define REG_INDEXED_THRESHOLD	(1 << 5)
417 
418 /* DRIVER DATA STRUCTURES and UTILITIES */
419 struct net2272_ep {
420 	struct usb_ep ep;
421 	struct net2272 *dev;
422 	unsigned long irqs;
423 
424 	/* analogous to a host-side qh */
425 	struct list_head queue;
426 	const struct usb_endpoint_descriptor *desc;
427 	unsigned num:8,
428 	         fifo_size:12,
429 	         stopped:1,
430 	         wedged:1,
431 	         is_in:1,
432 	         is_iso:1,
433 	         dma:1,
434 	         not_empty:1;
435 };
436 
437 struct net2272 {
438 	/* each device provides one gadget, several endpoints */
439 	struct usb_gadget gadget;
440 	struct device *dev;
441 	unsigned short dev_id;
442 
443 	spinlock_t lock;
444 	struct net2272_ep ep[4];
445 	struct usb_gadget_driver *driver;
446 	unsigned protocol_stall:1,
447 	         softconnect:1,
448 	         wakeup:1,
449 	         dma_eot_polarity:1,
450 	         dma_dack_polarity:1,
451 	         dma_dreq_polarity:1,
452 	         dma_busy:1;
453 	u16 chiprev;
454 	u8 pagesel;
455 
456 	unsigned int irq;
457 	unsigned short fifo_mode;
458 
459 	unsigned int base_shift;
460 	u16 __iomem *base_addr;
461 	union {
462 #ifdef CONFIG_USB_PCI
463 		struct {
464 			void __iomem *plx9054_base_addr;
465 			void __iomem *epld_base_addr;
466 		} rdk1;
467 		struct {
468 			/* Bar0, Bar1 is base_addr both mem-mapped */
469 			void __iomem *fpga_base_addr;
470 		} rdk2;
471 #endif
472 	};
473 };
474 
475 static void __iomem *
476 net2272_reg_addr(struct net2272 *dev, unsigned int reg)
477 {
478 	return dev->base_addr + (reg << dev->base_shift);
479 }
480 
481 static void
482 net2272_write(struct net2272 *dev, unsigned int reg, u8 value)
483 {
484 	if (reg >= REG_INDEXED_THRESHOLD) {
485 		/*
486 		 * Indexed register; use REGADDRPTR/REGDATA
487 		 *  - Save and restore REGADDRPTR. This prevents REGADDRPTR from
488 		 *    changes between other code sections, but it is time consuming.
489 		 *  - Performance tips: either do not save and restore REGADDRPTR (if it
490 		 *    is safe) or do save/restore operations only in critical sections.
491 		u8 tmp = readb(dev->base_addr + REGADDRPTR);
492 		 */
493 		writeb((u8)reg, net2272_reg_addr(dev, REGADDRPTR));
494 		writeb(value, net2272_reg_addr(dev, REGDATA));
495 		/* writeb(tmp, net2272_reg_addr(dev, REGADDRPTR)); */
496 	} else
497 		writeb(value, net2272_reg_addr(dev, reg));
498 }
499 
500 static u8
501 net2272_read(struct net2272 *dev, unsigned int reg)
502 {
503 	u8 ret;
504 
505 	if (reg >= REG_INDEXED_THRESHOLD) {
506 		/*
507 		 * Indexed register; use REGADDRPTR/REGDATA
508 		 *  - Save and restore REGADDRPTR. This prevents REGADDRPTR from
509 		 *    changes between other code sections, but it is time consuming.
510 		 *  - Performance tips: either do not save and restore REGADDRPTR (if it
511 		 *    is safe) or do save/restore operations only in critical sections.
512 		u8 tmp = readb(dev->base_addr + REGADDRPTR);
513 		 */
514 		writeb((u8)reg, net2272_reg_addr(dev, REGADDRPTR));
515 		ret = readb(net2272_reg_addr(dev, REGDATA));
516 		/* writeb(tmp, net2272_reg_addr(dev, REGADDRPTR)); */
517 	} else
518 		ret = readb(net2272_reg_addr(dev, reg));
519 
520 	return ret;
521 }
522 
523 static void
524 net2272_ep_write(struct net2272_ep *ep, unsigned int reg, u8 value)
525 {
526 	struct net2272 *dev = ep->dev;
527 
528 	if (dev->pagesel != ep->num) {
529 		net2272_write(dev, PAGESEL, ep->num);
530 		dev->pagesel = ep->num;
531 	}
532 	net2272_write(dev, reg, value);
533 }
534 
535 static u8
536 net2272_ep_read(struct net2272_ep *ep, unsigned int reg)
537 {
538 	struct net2272 *dev = ep->dev;
539 
540 	if (dev->pagesel != ep->num) {
541 		net2272_write(dev, PAGESEL, ep->num);
542 		dev->pagesel = ep->num;
543 	}
544 	return net2272_read(dev, reg);
545 }
546 
547 static void allow_status(struct net2272_ep *ep)
548 {
549 	/* ep0 only */
550 	net2272_ep_write(ep, EP_RSPCLR,
551 		(1 << CONTROL_STATUS_PHASE_HANDSHAKE) |
552 		(1 << ALT_NAK_OUT_PACKETS) |
553 		(1 << NAK_OUT_PACKETS_MODE));
554 	ep->stopped = 1;
555 }
556 
557 static void set_halt(struct net2272_ep *ep)
558 {
559 	/* ep0 and bulk/intr endpoints */
560 	net2272_ep_write(ep, EP_RSPCLR, 1 << CONTROL_STATUS_PHASE_HANDSHAKE);
561 	net2272_ep_write(ep, EP_RSPSET, 1 << ENDPOINT_HALT);
562 }
563 
564 static void clear_halt(struct net2272_ep *ep)
565 {
566 	/* ep0 and bulk/intr endpoints */
567 	net2272_ep_write(ep, EP_RSPCLR,
568 		(1 << ENDPOINT_HALT) | (1 << ENDPOINT_TOGGLE));
569 }
570 
571 /* count (<= 4) bytes in the next fifo write will be valid */
572 static void set_fifo_bytecount(struct net2272_ep *ep, unsigned count)
573 {
574 	/* net2272_ep_write will truncate to u8 for us */
575 	net2272_ep_write(ep, EP_TRANSFER2, count >> 16);
576 	net2272_ep_write(ep, EP_TRANSFER1, count >> 8);
577 	net2272_ep_write(ep, EP_TRANSFER0, count);
578 }
579 
580 struct net2272_request {
581 	struct usb_request req;
582 	struct list_head queue;
583 	unsigned mapped:1,
584 	         valid:1;
585 };
586 
587 #endif
588