GNU Linux-libre 4.19.245-gnu1
[releases.git] / drivers / usb / gadget / udc / net2272.h
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