1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * MAX3421 Host Controller driver for USB.
4 *
5 * Author: David Mosberger-Tang <davidm@egauge.net>
6 *
7 * (C) Copyright 2014 David Mosberger-Tang <davidm@egauge.net>
8 *
9 * MAX3421 is a chip implementing a USB 2.0 Full-/Low-Speed host
10 * controller on a SPI bus.
11 *
12 * Based on:
13 * o MAX3421E datasheet
14 * https://datasheets.maximintegrated.com/en/ds/MAX3421E.pdf
15 * o MAX3421E Programming Guide
16 * https://www.hdl.co.jp/ftpdata/utl-001/AN3785.pdf
17 * o gadget/dummy_hcd.c
18 * For USB HCD implementation.
19 * o Arduino MAX3421 driver
20 * https://github.com/felis/USB_Host_Shield_2.0/blob/master/Usb.cpp
21 *
22 * This file is licenced under the GPL v2.
23 *
24 * Important note on worst-case (full-speed) packet size constraints
25 * (See USB 2.0 Section 5.6.3 and following):
26 *
27 * - control: 64 bytes
28 * - isochronous: 1023 bytes
29 * - interrupt: 64 bytes
30 * - bulk: 64 bytes
31 *
32 * Since the MAX3421 FIFO size is 64 bytes, we do not have to work about
33 * multi-FIFO writes/reads for a single USB packet *except* for isochronous
34 * transfers. We don't support isochronous transfers at this time, so we
35 * just assume that a USB packet always fits into a single FIFO buffer.
36 *
37 * NOTE: The June 2006 version of "MAX3421E Programming Guide"
38 * (AN3785) has conflicting info for the RCVDAVIRQ bit:
39 *
40 * The description of RCVDAVIRQ says "The CPU *must* clear
41 * this IRQ bit (by writing a 1 to it) before reading the
42 * RCVFIFO data.
43 *
44 * However, the earlier section on "Programming BULK-IN
45 * Transfers" says * that:
46 *
47 * After the CPU retrieves the data, it clears the
48 * RCVDAVIRQ bit.
49 *
50 * The December 2006 version has been corrected and it consistently
51 * states the second behavior is the correct one.
52 *
53 * Synchronous SPI transactions sleep so we can't perform any such
54 * transactions while holding a spin-lock (and/or while interrupts are
55 * masked). To achieve this, all SPI transactions are issued from a
56 * single thread (max3421_spi_thread).
57 */
58
59 #include <linux/jiffies.h>
60 #include <linux/module.h>
61 #include <linux/spi/spi.h>
62 #include <linux/usb.h>
63 #include <linux/usb/hcd.h>
64 #include <linux/of.h>
65
66 #include <linux/platform_data/max3421-hcd.h>
67
68 #define DRIVER_DESC "MAX3421 USB Host-Controller Driver"
69 #define DRIVER_VERSION "1.0"
70
71 /* 11-bit counter that wraps around (USB 2.0 Section 8.3.3): */
72 #define USB_MAX_FRAME_NUMBER 0x7ff
73 #define USB_MAX_RETRIES 3 /* # of retries before error is reported */
74
75 #define POWER_BUDGET 500 /* in mA; use 8 for low-power port testing */
76
77 /* Port-change mask: */
78 #define PORT_C_MASK ((USB_PORT_STAT_C_CONNECTION | \
79 USB_PORT_STAT_C_ENABLE | \
80 USB_PORT_STAT_C_SUSPEND | \
81 USB_PORT_STAT_C_OVERCURRENT | \
82 USB_PORT_STAT_C_RESET) << 16)
83
84 #define MAX3421_GPOUT_COUNT 8
85
86 enum max3421_rh_state {
87 MAX3421_RH_RESET,
88 MAX3421_RH_SUSPENDED,
89 MAX3421_RH_RUNNING
90 };
91
92 enum pkt_state {
93 PKT_STATE_SETUP, /* waiting to send setup packet to ctrl pipe */
94 PKT_STATE_TRANSFER, /* waiting to xfer transfer_buffer */
95 PKT_STATE_TERMINATE /* waiting to terminate control transfer */
96 };
97
98 enum scheduling_pass {
99 SCHED_PASS_PERIODIC,
100 SCHED_PASS_NON_PERIODIC,
101 SCHED_PASS_DONE
102 };
103
104 /* Bit numbers for max3421_hcd->todo: */
105 enum {
106 ENABLE_IRQ = 0,
107 RESET_HCD,
108 RESET_PORT,
109 CHECK_UNLINK,
110 IOPIN_UPDATE
111 };
112
113 struct max3421_dma_buf {
114 u8 data[2];
115 };
116
117 struct max3421_hcd {
118 spinlock_t lock;
119
120 struct task_struct *spi_thread;
121
122 enum max3421_rh_state rh_state;
123 /* lower 16 bits contain port status, upper 16 bits the change mask: */
124 u32 port_status;
125
126 unsigned active:1;
127
128 struct list_head ep_list; /* list of EP's with work */
129
130 /*
131 * The following are owned by spi_thread (may be accessed by
132 * SPI-thread without acquiring the HCD lock:
133 */
134 u8 rev; /* chip revision */
135 u16 frame_number;
136 /*
137 * kmalloc'd buffers guaranteed to be in separate (DMA)
138 * cache-lines:
139 */
140 struct max3421_dma_buf *tx;
141 struct max3421_dma_buf *rx;
142 /*
143 * URB we're currently processing. Must not be reset to NULL
144 * unless MAX3421E chip is idle:
145 */
146 struct urb *curr_urb;
147 enum scheduling_pass sched_pass;
148 int urb_done; /* > 0 -> no errors, < 0: errno */
149 size_t curr_len;
150 u8 hien;
151 u8 mode;
152 u8 iopins[2];
153 unsigned long todo;
154 #ifdef DEBUG
155 unsigned long err_stat[16];
156 #endif
157 };
158
159 struct max3421_ep {
160 struct usb_host_endpoint *ep;
161 struct list_head ep_list;
162 u32 naks;
163 u16 last_active; /* frame # this ep was last active */
164 enum pkt_state pkt_state;
165 u8 retries;
166 u8 retransmit; /* packet needs retransmission */
167 };
168
169 #define MAX3421_FIFO_SIZE 64
170
171 #define MAX3421_SPI_DIR_RD 0 /* read register from MAX3421 */
172 #define MAX3421_SPI_DIR_WR 1 /* write register to MAX3421 */
173
174 /* SPI commands: */
175 #define MAX3421_SPI_DIR_SHIFT 1
176 #define MAX3421_SPI_REG_SHIFT 3
177
178 #define MAX3421_REG_RCVFIFO 1
179 #define MAX3421_REG_SNDFIFO 2
180 #define MAX3421_REG_SUDFIFO 4
181 #define MAX3421_REG_RCVBC 6
182 #define MAX3421_REG_SNDBC 7
183 #define MAX3421_REG_USBIRQ 13
184 #define MAX3421_REG_USBIEN 14
185 #define MAX3421_REG_USBCTL 15
186 #define MAX3421_REG_CPUCTL 16
187 #define MAX3421_REG_PINCTL 17
188 #define MAX3421_REG_REVISION 18
189 #define MAX3421_REG_IOPINS1 20
190 #define MAX3421_REG_IOPINS2 21
191 #define MAX3421_REG_GPINIRQ 22
192 #define MAX3421_REG_GPINIEN 23
193 #define MAX3421_REG_GPINPOL 24
194 #define MAX3421_REG_HIRQ 25
195 #define MAX3421_REG_HIEN 26
196 #define MAX3421_REG_MODE 27
197 #define MAX3421_REG_PERADDR 28
198 #define MAX3421_REG_HCTL 29
199 #define MAX3421_REG_HXFR 30
200 #define MAX3421_REG_HRSL 31
201
202 enum {
203 MAX3421_USBIRQ_OSCOKIRQ_BIT = 0,
204 MAX3421_USBIRQ_NOVBUSIRQ_BIT = 5,
205 MAX3421_USBIRQ_VBUSIRQ_BIT
206 };
207
208 enum {
209 MAX3421_CPUCTL_IE_BIT = 0,
210 MAX3421_CPUCTL_PULSEWID0_BIT = 6,
211 MAX3421_CPUCTL_PULSEWID1_BIT
212 };
213
214 enum {
215 MAX3421_USBCTL_PWRDOWN_BIT = 4,
216 MAX3421_USBCTL_CHIPRES_BIT
217 };
218
219 enum {
220 MAX3421_PINCTL_GPXA_BIT = 0,
221 MAX3421_PINCTL_GPXB_BIT,
222 MAX3421_PINCTL_POSINT_BIT,
223 MAX3421_PINCTL_INTLEVEL_BIT,
224 MAX3421_PINCTL_FDUPSPI_BIT,
225 MAX3421_PINCTL_EP0INAK_BIT,
226 MAX3421_PINCTL_EP2INAK_BIT,
227 MAX3421_PINCTL_EP3INAK_BIT,
228 };
229
230 enum {
231 MAX3421_HI_BUSEVENT_BIT = 0, /* bus-reset/-resume */
232 MAX3421_HI_RWU_BIT, /* remote wakeup */
233 MAX3421_HI_RCVDAV_BIT, /* receive FIFO data available */
234 MAX3421_HI_SNDBAV_BIT, /* send buffer available */
235 MAX3421_HI_SUSDN_BIT, /* suspend operation done */
236 MAX3421_HI_CONDET_BIT, /* peripheral connect/disconnect */
237 MAX3421_HI_FRAME_BIT, /* frame generator */
238 MAX3421_HI_HXFRDN_BIT, /* host transfer done */
239 };
240
241 enum {
242 MAX3421_HCTL_BUSRST_BIT = 0,
243 MAX3421_HCTL_FRMRST_BIT,
244 MAX3421_HCTL_SAMPLEBUS_BIT,
245 MAX3421_HCTL_SIGRSM_BIT,
246 MAX3421_HCTL_RCVTOG0_BIT,
247 MAX3421_HCTL_RCVTOG1_BIT,
248 MAX3421_HCTL_SNDTOG0_BIT,
249 MAX3421_HCTL_SNDTOG1_BIT
250 };
251
252 enum {
253 MAX3421_MODE_HOST_BIT = 0,
254 MAX3421_MODE_LOWSPEED_BIT,
255 MAX3421_MODE_HUBPRE_BIT,
256 MAX3421_MODE_SOFKAENAB_BIT,
257 MAX3421_MODE_SEPIRQ_BIT,
258 MAX3421_MODE_DELAYISO_BIT,
259 MAX3421_MODE_DMPULLDN_BIT,
260 MAX3421_MODE_DPPULLDN_BIT
261 };
262
263 enum {
264 MAX3421_HRSL_OK = 0,
265 MAX3421_HRSL_BUSY,
266 MAX3421_HRSL_BADREQ,
267 MAX3421_HRSL_UNDEF,
268 MAX3421_HRSL_NAK,
269 MAX3421_HRSL_STALL,
270 MAX3421_HRSL_TOGERR,
271 MAX3421_HRSL_WRONGPID,
272 MAX3421_HRSL_BADBC,
273 MAX3421_HRSL_PIDERR,
274 MAX3421_HRSL_PKTERR,
275 MAX3421_HRSL_CRCERR,
276 MAX3421_HRSL_KERR,
277 MAX3421_HRSL_JERR,
278 MAX3421_HRSL_TIMEOUT,
279 MAX3421_HRSL_BABBLE,
280 MAX3421_HRSL_RESULT_MASK = 0xf,
281 MAX3421_HRSL_RCVTOGRD_BIT = 4,
282 MAX3421_HRSL_SNDTOGRD_BIT,
283 MAX3421_HRSL_KSTATUS_BIT,
284 MAX3421_HRSL_JSTATUS_BIT
285 };
286
287 /* Return same error-codes as ohci.h:cc_to_error: */
288 static const int hrsl_to_error[] = {
289 [MAX3421_HRSL_OK] = 0,
290 [MAX3421_HRSL_BUSY] = -EINVAL,
291 [MAX3421_HRSL_BADREQ] = -EINVAL,
292 [MAX3421_HRSL_UNDEF] = -EINVAL,
293 [MAX3421_HRSL_NAK] = -EAGAIN,
294 [MAX3421_HRSL_STALL] = -EPIPE,
295 [MAX3421_HRSL_TOGERR] = -EILSEQ,
296 [MAX3421_HRSL_WRONGPID] = -EPROTO,
297 [MAX3421_HRSL_BADBC] = -EREMOTEIO,
298 [MAX3421_HRSL_PIDERR] = -EPROTO,
299 [MAX3421_HRSL_PKTERR] = -EPROTO,
300 [MAX3421_HRSL_CRCERR] = -EILSEQ,
301 [MAX3421_HRSL_KERR] = -EIO,
302 [MAX3421_HRSL_JERR] = -EIO,
303 [MAX3421_HRSL_TIMEOUT] = -ETIME,
304 [MAX3421_HRSL_BABBLE] = -EOVERFLOW
305 };
306
307 /*
308 * See https://www.beyondlogic.org/usbnutshell/usb4.shtml#Control for a
309 * reasonable overview of how control transfers use the IN/OUT
310 * tokens.
311 */
312 #define MAX3421_HXFR_BULK_IN(ep) (0x00 | (ep)) /* bulk or interrupt */
313 #define MAX3421_HXFR_SETUP 0x10
314 #define MAX3421_HXFR_BULK_OUT(ep) (0x20 | (ep)) /* bulk or interrupt */
315 #define MAX3421_HXFR_ISO_IN(ep) (0x40 | (ep))
316 #define MAX3421_HXFR_ISO_OUT(ep) (0x60 | (ep))
317 #define MAX3421_HXFR_HS_IN 0x80 /* handshake in */
318 #define MAX3421_HXFR_HS_OUT 0xa0 /* handshake out */
319
320 #define field(val, bit) ((val) << (bit))
321
322 static inline s16
frame_diff(u16 left,u16 right)323 frame_diff(u16 left, u16 right)
324 {
325 return ((unsigned) (left - right)) % (USB_MAX_FRAME_NUMBER + 1);
326 }
327
328 static inline struct max3421_hcd *
hcd_to_max3421(struct usb_hcd * hcd)329 hcd_to_max3421(struct usb_hcd *hcd)
330 {
331 return (struct max3421_hcd *) hcd->hcd_priv;
332 }
333
334 static inline struct usb_hcd *
max3421_to_hcd(struct max3421_hcd * max3421_hcd)335 max3421_to_hcd(struct max3421_hcd *max3421_hcd)
336 {
337 return container_of((void *) max3421_hcd, struct usb_hcd, hcd_priv);
338 }
339
340 static u8
spi_rd8(struct usb_hcd * hcd,unsigned int reg)341 spi_rd8(struct usb_hcd *hcd, unsigned int reg)
342 {
343 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
344 struct spi_device *spi = to_spi_device(hcd->self.controller);
345 struct spi_transfer transfer;
346 struct spi_message msg;
347
348 memset(&transfer, 0, sizeof(transfer));
349
350 spi_message_init(&msg);
351
352 max3421_hcd->tx->data[0] =
353 (field(reg, MAX3421_SPI_REG_SHIFT) |
354 field(MAX3421_SPI_DIR_RD, MAX3421_SPI_DIR_SHIFT));
355
356 transfer.tx_buf = max3421_hcd->tx->data;
357 transfer.rx_buf = max3421_hcd->rx->data;
358 transfer.len = 2;
359
360 spi_message_add_tail(&transfer, &msg);
361 spi_sync(spi, &msg);
362
363 return max3421_hcd->rx->data[1];
364 }
365
366 static void
spi_wr8(struct usb_hcd * hcd,unsigned int reg,u8 val)367 spi_wr8(struct usb_hcd *hcd, unsigned int reg, u8 val)
368 {
369 struct spi_device *spi = to_spi_device(hcd->self.controller);
370 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
371 struct spi_transfer transfer;
372 struct spi_message msg;
373
374 memset(&transfer, 0, sizeof(transfer));
375
376 spi_message_init(&msg);
377
378 max3421_hcd->tx->data[0] =
379 (field(reg, MAX3421_SPI_REG_SHIFT) |
380 field(MAX3421_SPI_DIR_WR, MAX3421_SPI_DIR_SHIFT));
381 max3421_hcd->tx->data[1] = val;
382
383 transfer.tx_buf = max3421_hcd->tx->data;
384 transfer.len = 2;
385
386 spi_message_add_tail(&transfer, &msg);
387 spi_sync(spi, &msg);
388 }
389
390 static void
spi_rd_buf(struct usb_hcd * hcd,unsigned int reg,void * buf,size_t len)391 spi_rd_buf(struct usb_hcd *hcd, unsigned int reg, void *buf, size_t len)
392 {
393 struct spi_device *spi = to_spi_device(hcd->self.controller);
394 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
395 struct spi_transfer transfer[2];
396 struct spi_message msg;
397
398 memset(transfer, 0, sizeof(transfer));
399
400 spi_message_init(&msg);
401
402 max3421_hcd->tx->data[0] =
403 (field(reg, MAX3421_SPI_REG_SHIFT) |
404 field(MAX3421_SPI_DIR_RD, MAX3421_SPI_DIR_SHIFT));
405 transfer[0].tx_buf = max3421_hcd->tx->data;
406 transfer[0].len = 1;
407
408 transfer[1].rx_buf = buf;
409 transfer[1].len = len;
410
411 spi_message_add_tail(&transfer[0], &msg);
412 spi_message_add_tail(&transfer[1], &msg);
413 spi_sync(spi, &msg);
414 }
415
416 static void
spi_wr_buf(struct usb_hcd * hcd,unsigned int reg,void * buf,size_t len)417 spi_wr_buf(struct usb_hcd *hcd, unsigned int reg, void *buf, size_t len)
418 {
419 struct spi_device *spi = to_spi_device(hcd->self.controller);
420 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
421 struct spi_transfer transfer[2];
422 struct spi_message msg;
423
424 memset(transfer, 0, sizeof(transfer));
425
426 spi_message_init(&msg);
427
428 max3421_hcd->tx->data[0] =
429 (field(reg, MAX3421_SPI_REG_SHIFT) |
430 field(MAX3421_SPI_DIR_WR, MAX3421_SPI_DIR_SHIFT));
431
432 transfer[0].tx_buf = max3421_hcd->tx->data;
433 transfer[0].len = 1;
434
435 transfer[1].tx_buf = buf;
436 transfer[1].len = len;
437
438 spi_message_add_tail(&transfer[0], &msg);
439 spi_message_add_tail(&transfer[1], &msg);
440 spi_sync(spi, &msg);
441 }
442
443 /*
444 * Figure out the correct setting for the LOWSPEED and HUBPRE mode
445 * bits. The HUBPRE bit needs to be set when MAX3421E operates at
446 * full speed, but it's talking to a low-speed device (i.e., through a
447 * hub). Setting that bit ensures that every low-speed packet is
448 * preceded by a full-speed PRE PID. Possible configurations:
449 *
450 * Hub speed: Device speed: => LOWSPEED bit: HUBPRE bit:
451 * FULL FULL => 0 0
452 * FULL LOW => 1 1
453 * LOW LOW => 1 0
454 * LOW FULL => 1 0
455 */
456 static void
max3421_set_speed(struct usb_hcd * hcd,struct usb_device * dev)457 max3421_set_speed(struct usb_hcd *hcd, struct usb_device *dev)
458 {
459 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
460 u8 mode_lowspeed, mode_hubpre, mode = max3421_hcd->mode;
461
462 mode_lowspeed = BIT(MAX3421_MODE_LOWSPEED_BIT);
463 mode_hubpre = BIT(MAX3421_MODE_HUBPRE_BIT);
464 if (max3421_hcd->port_status & USB_PORT_STAT_LOW_SPEED) {
465 mode |= mode_lowspeed;
466 mode &= ~mode_hubpre;
467 } else if (dev->speed == USB_SPEED_LOW) {
468 mode |= mode_lowspeed | mode_hubpre;
469 } else {
470 mode &= ~(mode_lowspeed | mode_hubpre);
471 }
472 if (mode != max3421_hcd->mode) {
473 max3421_hcd->mode = mode;
474 spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
475 }
476
477 }
478
479 /*
480 * Caller must NOT hold HCD spinlock.
481 */
482 static void
max3421_set_address(struct usb_hcd * hcd,struct usb_device * dev,int epnum)483 max3421_set_address(struct usb_hcd *hcd, struct usb_device *dev, int epnum)
484 {
485 int rcvtog, sndtog;
486 u8 hctl;
487
488 /* setup new endpoint's toggle bits: */
489 rcvtog = usb_gettoggle(dev, epnum, 0);
490 sndtog = usb_gettoggle(dev, epnum, 1);
491 hctl = (BIT(rcvtog + MAX3421_HCTL_RCVTOG0_BIT) |
492 BIT(sndtog + MAX3421_HCTL_SNDTOG0_BIT));
493
494 spi_wr8(hcd, MAX3421_REG_HCTL, hctl);
495
496 /*
497 * Note: devnum for one and the same device can change during
498 * address-assignment so it's best to just always load the
499 * address whenever the end-point changed/was forced.
500 */
501 spi_wr8(hcd, MAX3421_REG_PERADDR, dev->devnum);
502 }
503
504 static int
max3421_ctrl_setup(struct usb_hcd * hcd,struct urb * urb)505 max3421_ctrl_setup(struct usb_hcd *hcd, struct urb *urb)
506 {
507 spi_wr_buf(hcd, MAX3421_REG_SUDFIFO, urb->setup_packet, 8);
508 return MAX3421_HXFR_SETUP;
509 }
510
511 static int
max3421_transfer_in(struct usb_hcd * hcd,struct urb * urb)512 max3421_transfer_in(struct usb_hcd *hcd, struct urb *urb)
513 {
514 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
515 int epnum = usb_pipeendpoint(urb->pipe);
516
517 max3421_hcd->curr_len = 0;
518 max3421_hcd->hien |= BIT(MAX3421_HI_RCVDAV_BIT);
519 return MAX3421_HXFR_BULK_IN(epnum);
520 }
521
522 static int
max3421_transfer_out(struct usb_hcd * hcd,struct urb * urb,int fast_retransmit)523 max3421_transfer_out(struct usb_hcd *hcd, struct urb *urb, int fast_retransmit)
524 {
525 struct spi_device *spi = to_spi_device(hcd->self.controller);
526 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
527 int epnum = usb_pipeendpoint(urb->pipe);
528 u32 max_packet;
529 void *src;
530
531 src = urb->transfer_buffer + urb->actual_length;
532
533 if (fast_retransmit) {
534 if (max3421_hcd->rev == 0x12) {
535 /* work around rev 0x12 bug: */
536 spi_wr8(hcd, MAX3421_REG_SNDBC, 0);
537 spi_wr8(hcd, MAX3421_REG_SNDFIFO, ((u8 *) src)[0]);
538 spi_wr8(hcd, MAX3421_REG_SNDBC, max3421_hcd->curr_len);
539 }
540 return MAX3421_HXFR_BULK_OUT(epnum);
541 }
542
543 max_packet = usb_maxpacket(urb->dev, urb->pipe);
544
545 if (max_packet > MAX3421_FIFO_SIZE) {
546 /*
547 * We do not support isochronous transfers at this
548 * time.
549 */
550 dev_err(&spi->dev,
551 "%s: packet-size of %u too big (limit is %u bytes)",
552 __func__, max_packet, MAX3421_FIFO_SIZE);
553 max3421_hcd->urb_done = -EMSGSIZE;
554 return -EMSGSIZE;
555 }
556 max3421_hcd->curr_len = min((urb->transfer_buffer_length -
557 urb->actual_length), max_packet);
558
559 spi_wr_buf(hcd, MAX3421_REG_SNDFIFO, src, max3421_hcd->curr_len);
560 spi_wr8(hcd, MAX3421_REG_SNDBC, max3421_hcd->curr_len);
561 return MAX3421_HXFR_BULK_OUT(epnum);
562 }
563
564 /*
565 * Issue the next host-transfer command.
566 * Caller must NOT hold HCD spinlock.
567 */
568 static void
max3421_next_transfer(struct usb_hcd * hcd,int fast_retransmit)569 max3421_next_transfer(struct usb_hcd *hcd, int fast_retransmit)
570 {
571 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
572 struct urb *urb = max3421_hcd->curr_urb;
573 struct max3421_ep *max3421_ep;
574 int cmd = -EINVAL;
575
576 if (!urb)
577 return; /* nothing to do */
578
579 max3421_ep = urb->ep->hcpriv;
580
581 switch (max3421_ep->pkt_state) {
582 case PKT_STATE_SETUP:
583 cmd = max3421_ctrl_setup(hcd, urb);
584 break;
585
586 case PKT_STATE_TRANSFER:
587 if (usb_urb_dir_in(urb))
588 cmd = max3421_transfer_in(hcd, urb);
589 else
590 cmd = max3421_transfer_out(hcd, urb, fast_retransmit);
591 break;
592
593 case PKT_STATE_TERMINATE:
594 /*
595 * IN transfers are terminated with HS_OUT token,
596 * OUT transfers with HS_IN:
597 */
598 if (usb_urb_dir_in(urb))
599 cmd = MAX3421_HXFR_HS_OUT;
600 else
601 cmd = MAX3421_HXFR_HS_IN;
602 break;
603 }
604
605 if (cmd < 0)
606 return;
607
608 /* issue the command and wait for host-xfer-done interrupt: */
609
610 spi_wr8(hcd, MAX3421_REG_HXFR, cmd);
611 max3421_hcd->hien |= BIT(MAX3421_HI_HXFRDN_BIT);
612 }
613
614 /*
615 * Find the next URB to process and start its execution.
616 *
617 * At this time, we do not anticipate ever connecting a USB hub to the
618 * MAX3421 chip, so at most USB device can be connected and we can use
619 * a simplistic scheduler: at the start of a frame, schedule all
620 * periodic transfers. Once that is done, use the remainder of the
621 * frame to process non-periodic (bulk & control) transfers.
622 *
623 * Preconditions:
624 * o Caller must NOT hold HCD spinlock.
625 * o max3421_hcd->curr_urb MUST BE NULL.
626 * o MAX3421E chip must be idle.
627 */
628 static int
max3421_select_and_start_urb(struct usb_hcd * hcd)629 max3421_select_and_start_urb(struct usb_hcd *hcd)
630 {
631 struct spi_device *spi = to_spi_device(hcd->self.controller);
632 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
633 struct urb *urb, *curr_urb = NULL;
634 struct max3421_ep *max3421_ep;
635 int epnum;
636 struct usb_host_endpoint *ep;
637 struct list_head *pos;
638 unsigned long flags;
639
640 spin_lock_irqsave(&max3421_hcd->lock, flags);
641
642 for (;
643 max3421_hcd->sched_pass < SCHED_PASS_DONE;
644 ++max3421_hcd->sched_pass)
645 list_for_each(pos, &max3421_hcd->ep_list) {
646 urb = NULL;
647 max3421_ep = container_of(pos, struct max3421_ep,
648 ep_list);
649 ep = max3421_ep->ep;
650
651 switch (usb_endpoint_type(&ep->desc)) {
652 case USB_ENDPOINT_XFER_ISOC:
653 case USB_ENDPOINT_XFER_INT:
654 if (max3421_hcd->sched_pass !=
655 SCHED_PASS_PERIODIC)
656 continue;
657 break;
658
659 case USB_ENDPOINT_XFER_CONTROL:
660 case USB_ENDPOINT_XFER_BULK:
661 if (max3421_hcd->sched_pass !=
662 SCHED_PASS_NON_PERIODIC)
663 continue;
664 break;
665 }
666
667 if (list_empty(&ep->urb_list))
668 continue; /* nothing to do */
669 urb = list_first_entry(&ep->urb_list, struct urb,
670 urb_list);
671 if (urb->unlinked) {
672 dev_dbg(&spi->dev, "%s: URB %p unlinked=%d",
673 __func__, urb, urb->unlinked);
674 max3421_hcd->curr_urb = urb;
675 max3421_hcd->urb_done = 1;
676 spin_unlock_irqrestore(&max3421_hcd->lock,
677 flags);
678 return 1;
679 }
680
681 switch (usb_endpoint_type(&ep->desc)) {
682 case USB_ENDPOINT_XFER_CONTROL:
683 /*
684 * Allow one control transaction per
685 * frame per endpoint:
686 */
687 if (frame_diff(max3421_ep->last_active,
688 max3421_hcd->frame_number) == 0)
689 continue;
690 break;
691
692 case USB_ENDPOINT_XFER_BULK:
693 if (max3421_ep->retransmit
694 && (frame_diff(max3421_ep->last_active,
695 max3421_hcd->frame_number)
696 == 0))
697 /*
698 * We already tried this EP
699 * during this frame and got a
700 * NAK or error; wait for next frame
701 */
702 continue;
703 break;
704
705 case USB_ENDPOINT_XFER_ISOC:
706 case USB_ENDPOINT_XFER_INT:
707 if (frame_diff(max3421_hcd->frame_number,
708 max3421_ep->last_active)
709 < urb->interval)
710 /*
711 * We already processed this
712 * end-point in the current
713 * frame
714 */
715 continue;
716 break;
717 }
718
719 /* move current ep to tail: */
720 list_move_tail(pos, &max3421_hcd->ep_list);
721 curr_urb = urb;
722 goto done;
723 }
724 done:
725 if (!curr_urb) {
726 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
727 return 0;
728 }
729
730 urb = max3421_hcd->curr_urb = curr_urb;
731 epnum = usb_endpoint_num(&urb->ep->desc);
732 if (max3421_ep->retransmit)
733 /* restart (part of) a USB transaction: */
734 max3421_ep->retransmit = 0;
735 else {
736 /* start USB transaction: */
737 if (usb_endpoint_xfer_control(&ep->desc)) {
738 /*
739 * See USB 2.0 spec section 8.6.1
740 * Initialization via SETUP Token:
741 */
742 usb_settoggle(urb->dev, epnum, 0, 1);
743 usb_settoggle(urb->dev, epnum, 1, 1);
744 max3421_ep->pkt_state = PKT_STATE_SETUP;
745 } else
746 max3421_ep->pkt_state = PKT_STATE_TRANSFER;
747 }
748
749 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
750
751 max3421_ep->last_active = max3421_hcd->frame_number;
752 max3421_set_address(hcd, urb->dev, epnum);
753 max3421_set_speed(hcd, urb->dev);
754 max3421_next_transfer(hcd, 0);
755 return 1;
756 }
757
758 /*
759 * Check all endpoints for URBs that got unlinked.
760 *
761 * Caller must NOT hold HCD spinlock.
762 */
763 static int
max3421_check_unlink(struct usb_hcd * hcd)764 max3421_check_unlink(struct usb_hcd *hcd)
765 {
766 struct spi_device *spi = to_spi_device(hcd->self.controller);
767 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
768 struct max3421_ep *max3421_ep;
769 struct usb_host_endpoint *ep;
770 struct urb *urb, *next;
771 unsigned long flags;
772 int retval = 0;
773
774 spin_lock_irqsave(&max3421_hcd->lock, flags);
775 list_for_each_entry(max3421_ep, &max3421_hcd->ep_list, ep_list) {
776 ep = max3421_ep->ep;
777 list_for_each_entry_safe(urb, next, &ep->urb_list, urb_list) {
778 if (urb->unlinked) {
779 retval = 1;
780 dev_dbg(&spi->dev, "%s: URB %p unlinked=%d",
781 __func__, urb, urb->unlinked);
782 usb_hcd_unlink_urb_from_ep(hcd, urb);
783 spin_unlock_irqrestore(&max3421_hcd->lock,
784 flags);
785 usb_hcd_giveback_urb(hcd, urb, 0);
786 spin_lock_irqsave(&max3421_hcd->lock, flags);
787 }
788 }
789 }
790 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
791 return retval;
792 }
793
794 /*
795 * Caller must NOT hold HCD spinlock.
796 */
797 static void
max3421_slow_retransmit(struct usb_hcd * hcd)798 max3421_slow_retransmit(struct usb_hcd *hcd)
799 {
800 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
801 struct urb *urb = max3421_hcd->curr_urb;
802 struct max3421_ep *max3421_ep;
803
804 max3421_ep = urb->ep->hcpriv;
805 max3421_ep->retransmit = 1;
806 max3421_hcd->curr_urb = NULL;
807 }
808
809 /*
810 * Caller must NOT hold HCD spinlock.
811 */
812 static void
max3421_recv_data_available(struct usb_hcd * hcd)813 max3421_recv_data_available(struct usb_hcd *hcd)
814 {
815 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
816 struct urb *urb = max3421_hcd->curr_urb;
817 size_t remaining, transfer_size;
818 u8 rcvbc;
819
820 rcvbc = spi_rd8(hcd, MAX3421_REG_RCVBC);
821
822 if (rcvbc > MAX3421_FIFO_SIZE)
823 rcvbc = MAX3421_FIFO_SIZE;
824 if (urb->actual_length >= urb->transfer_buffer_length)
825 remaining = 0;
826 else
827 remaining = urb->transfer_buffer_length - urb->actual_length;
828 transfer_size = rcvbc;
829 if (transfer_size > remaining)
830 transfer_size = remaining;
831 if (transfer_size > 0) {
832 void *dst = urb->transfer_buffer + urb->actual_length;
833
834 spi_rd_buf(hcd, MAX3421_REG_RCVFIFO, dst, transfer_size);
835 urb->actual_length += transfer_size;
836 max3421_hcd->curr_len = transfer_size;
837 }
838
839 /* ack the RCVDAV irq now that the FIFO has been read: */
840 spi_wr8(hcd, MAX3421_REG_HIRQ, BIT(MAX3421_HI_RCVDAV_BIT));
841 }
842
843 static void
max3421_handle_error(struct usb_hcd * hcd,u8 hrsl)844 max3421_handle_error(struct usb_hcd *hcd, u8 hrsl)
845 {
846 struct spi_device *spi = to_spi_device(hcd->self.controller);
847 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
848 u8 result_code = hrsl & MAX3421_HRSL_RESULT_MASK;
849 struct urb *urb = max3421_hcd->curr_urb;
850 struct max3421_ep *max3421_ep = urb->ep->hcpriv;
851 int switch_sndfifo;
852
853 /*
854 * If an OUT command results in any response other than OK
855 * (i.e., error or NAK), we have to perform a dummy-write to
856 * SNDBC so the FIFO gets switched back to us. Otherwise, we
857 * get out of sync with the SNDFIFO double buffer.
858 */
859 switch_sndfifo = (max3421_ep->pkt_state == PKT_STATE_TRANSFER &&
860 usb_urb_dir_out(urb));
861
862 switch (result_code) {
863 case MAX3421_HRSL_OK:
864 return; /* this shouldn't happen */
865
866 case MAX3421_HRSL_WRONGPID: /* received wrong PID */
867 case MAX3421_HRSL_BUSY: /* SIE busy */
868 case MAX3421_HRSL_BADREQ: /* bad val in HXFR */
869 case MAX3421_HRSL_UNDEF: /* reserved */
870 case MAX3421_HRSL_KERR: /* K-state instead of response */
871 case MAX3421_HRSL_JERR: /* J-state instead of response */
872 /*
873 * packet experienced an error that we cannot recover
874 * from; report error
875 */
876 max3421_hcd->urb_done = hrsl_to_error[result_code];
877 dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
878 __func__, hrsl);
879 break;
880
881 case MAX3421_HRSL_TOGERR:
882 if (usb_urb_dir_in(urb))
883 ; /* don't do anything (device will switch toggle) */
884 else {
885 /* flip the send toggle bit: */
886 int sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
887
888 sndtog ^= 1;
889 spi_wr8(hcd, MAX3421_REG_HCTL,
890 BIT(sndtog + MAX3421_HCTL_SNDTOG0_BIT));
891 }
892 fallthrough;
893 case MAX3421_HRSL_BADBC: /* bad byte count */
894 case MAX3421_HRSL_PIDERR: /* received PID is corrupted */
895 case MAX3421_HRSL_PKTERR: /* packet error (stuff, EOP) */
896 case MAX3421_HRSL_CRCERR: /* CRC error */
897 case MAX3421_HRSL_BABBLE: /* device talked too long */
898 case MAX3421_HRSL_TIMEOUT:
899 if (max3421_ep->retries++ < USB_MAX_RETRIES)
900 /* retry the packet again in the next frame */
901 max3421_slow_retransmit(hcd);
902 else {
903 /* Based on ohci.h cc_to_err[]: */
904 max3421_hcd->urb_done = hrsl_to_error[result_code];
905 dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
906 __func__, hrsl);
907 }
908 break;
909
910 case MAX3421_HRSL_STALL:
911 dev_dbg(&spi->dev, "%s: unexpected error HRSL=0x%02x",
912 __func__, hrsl);
913 max3421_hcd->urb_done = hrsl_to_error[result_code];
914 break;
915
916 case MAX3421_HRSL_NAK:
917 /*
918 * Device wasn't ready for data or has no data
919 * available: retry the packet again.
920 */
921 max3421_next_transfer(hcd, 1);
922 switch_sndfifo = 0;
923 break;
924 }
925 if (switch_sndfifo)
926 spi_wr8(hcd, MAX3421_REG_SNDBC, 0);
927 }
928
929 /*
930 * Caller must NOT hold HCD spinlock.
931 */
932 static int
max3421_transfer_in_done(struct usb_hcd * hcd,struct urb * urb)933 max3421_transfer_in_done(struct usb_hcd *hcd, struct urb *urb)
934 {
935 struct spi_device *spi = to_spi_device(hcd->self.controller);
936 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
937 u32 max_packet;
938
939 if (urb->actual_length >= urb->transfer_buffer_length)
940 return 1; /* read is complete, so we're done */
941
942 /*
943 * USB 2.0 Section 5.3.2 Pipes: packets must be full size
944 * except for last one.
945 */
946 max_packet = usb_maxpacket(urb->dev, urb->pipe);
947 if (max_packet > MAX3421_FIFO_SIZE) {
948 /*
949 * We do not support isochronous transfers at this
950 * time...
951 */
952 dev_err(&spi->dev,
953 "%s: packet-size of %u too big (limit is %u bytes)",
954 __func__, max_packet, MAX3421_FIFO_SIZE);
955 return -EINVAL;
956 }
957
958 if (max3421_hcd->curr_len < max_packet) {
959 if (urb->transfer_flags & URB_SHORT_NOT_OK) {
960 /*
961 * remaining > 0 and received an
962 * unexpected partial packet ->
963 * error
964 */
965 return -EREMOTEIO;
966 } else
967 /* short read, but it's OK */
968 return 1;
969 }
970 return 0; /* not done */
971 }
972
973 /*
974 * Caller must NOT hold HCD spinlock.
975 */
976 static int
max3421_transfer_out_done(struct usb_hcd * hcd,struct urb * urb)977 max3421_transfer_out_done(struct usb_hcd *hcd, struct urb *urb)
978 {
979 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
980
981 urb->actual_length += max3421_hcd->curr_len;
982 if (urb->actual_length < urb->transfer_buffer_length)
983 return 0;
984 if (urb->transfer_flags & URB_ZERO_PACKET) {
985 /*
986 * Some hardware needs a zero-size packet at the end
987 * of a bulk-out transfer if the last transfer was a
988 * full-sized packet (i.e., such hardware use <
989 * max_packet as an indicator that the end of the
990 * packet has been reached).
991 */
992 u32 max_packet = usb_maxpacket(urb->dev, urb->pipe);
993
994 if (max3421_hcd->curr_len == max_packet)
995 return 0;
996 }
997 return 1;
998 }
999
1000 /*
1001 * Caller must NOT hold HCD spinlock.
1002 */
1003 static void
max3421_host_transfer_done(struct usb_hcd * hcd)1004 max3421_host_transfer_done(struct usb_hcd *hcd)
1005 {
1006 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1007 struct urb *urb = max3421_hcd->curr_urb;
1008 struct max3421_ep *max3421_ep;
1009 u8 result_code, hrsl;
1010 int urb_done = 0;
1011
1012 max3421_hcd->hien &= ~(BIT(MAX3421_HI_HXFRDN_BIT) |
1013 BIT(MAX3421_HI_RCVDAV_BIT));
1014
1015 hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
1016 result_code = hrsl & MAX3421_HRSL_RESULT_MASK;
1017
1018 #ifdef DEBUG
1019 ++max3421_hcd->err_stat[result_code];
1020 #endif
1021
1022 max3421_ep = urb->ep->hcpriv;
1023
1024 if (unlikely(result_code != MAX3421_HRSL_OK)) {
1025 max3421_handle_error(hcd, hrsl);
1026 return;
1027 }
1028
1029 max3421_ep->naks = 0;
1030 max3421_ep->retries = 0;
1031 switch (max3421_ep->pkt_state) {
1032
1033 case PKT_STATE_SETUP:
1034 if (urb->transfer_buffer_length > 0)
1035 max3421_ep->pkt_state = PKT_STATE_TRANSFER;
1036 else
1037 max3421_ep->pkt_state = PKT_STATE_TERMINATE;
1038 break;
1039
1040 case PKT_STATE_TRANSFER:
1041 if (usb_urb_dir_in(urb))
1042 urb_done = max3421_transfer_in_done(hcd, urb);
1043 else
1044 urb_done = max3421_transfer_out_done(hcd, urb);
1045 if (urb_done > 0 && usb_pipetype(urb->pipe) == PIPE_CONTROL) {
1046 /*
1047 * We aren't really done - we still need to
1048 * terminate the control transfer:
1049 */
1050 max3421_hcd->urb_done = urb_done = 0;
1051 max3421_ep->pkt_state = PKT_STATE_TERMINATE;
1052 }
1053 break;
1054
1055 case PKT_STATE_TERMINATE:
1056 urb_done = 1;
1057 break;
1058 }
1059
1060 if (urb_done)
1061 max3421_hcd->urb_done = urb_done;
1062 else
1063 max3421_next_transfer(hcd, 0);
1064 }
1065
1066 /*
1067 * Caller must NOT hold HCD spinlock.
1068 */
1069 static void
max3421_detect_conn(struct usb_hcd * hcd)1070 max3421_detect_conn(struct usb_hcd *hcd)
1071 {
1072 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1073 unsigned int jk, have_conn = 0;
1074 u32 old_port_status, chg;
1075 unsigned long flags;
1076 u8 hrsl, mode;
1077
1078 hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
1079
1080 jk = ((((hrsl >> MAX3421_HRSL_JSTATUS_BIT) & 1) << 0) |
1081 (((hrsl >> MAX3421_HRSL_KSTATUS_BIT) & 1) << 1));
1082
1083 mode = max3421_hcd->mode;
1084
1085 switch (jk) {
1086 case 0x0: /* SE0: disconnect */
1087 /*
1088 * Turn off SOFKAENAB bit to avoid getting interrupt
1089 * every milli-second:
1090 */
1091 mode &= ~BIT(MAX3421_MODE_SOFKAENAB_BIT);
1092 break;
1093
1094 case 0x1: /* J=0,K=1: low-speed (in full-speed or vice versa) */
1095 case 0x2: /* J=1,K=0: full-speed (in full-speed or vice versa) */
1096 if (jk == 0x2)
1097 /* need to switch to the other speed: */
1098 mode ^= BIT(MAX3421_MODE_LOWSPEED_BIT);
1099 /* turn on SOFKAENAB bit: */
1100 mode |= BIT(MAX3421_MODE_SOFKAENAB_BIT);
1101 have_conn = 1;
1102 break;
1103
1104 case 0x3: /* illegal */
1105 break;
1106 }
1107
1108 max3421_hcd->mode = mode;
1109 spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
1110
1111 spin_lock_irqsave(&max3421_hcd->lock, flags);
1112 old_port_status = max3421_hcd->port_status;
1113 if (have_conn)
1114 max3421_hcd->port_status |= USB_PORT_STAT_CONNECTION;
1115 else
1116 max3421_hcd->port_status &= ~USB_PORT_STAT_CONNECTION;
1117 if (mode & BIT(MAX3421_MODE_LOWSPEED_BIT))
1118 max3421_hcd->port_status |= USB_PORT_STAT_LOW_SPEED;
1119 else
1120 max3421_hcd->port_status &= ~USB_PORT_STAT_LOW_SPEED;
1121 chg = (old_port_status ^ max3421_hcd->port_status);
1122 max3421_hcd->port_status |= chg << 16;
1123 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1124 }
1125
1126 static irqreturn_t
max3421_irq_handler(int irq,void * dev_id)1127 max3421_irq_handler(int irq, void *dev_id)
1128 {
1129 struct usb_hcd *hcd = dev_id;
1130 struct spi_device *spi = to_spi_device(hcd->self.controller);
1131 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1132
1133 if (max3421_hcd->spi_thread)
1134 wake_up_process(max3421_hcd->spi_thread);
1135 if (!test_and_set_bit(ENABLE_IRQ, &max3421_hcd->todo))
1136 disable_irq_nosync(spi->irq);
1137 return IRQ_HANDLED;
1138 }
1139
1140 #ifdef DEBUG
1141
1142 static void
dump_eps(struct usb_hcd * hcd)1143 dump_eps(struct usb_hcd *hcd)
1144 {
1145 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1146 struct max3421_ep *max3421_ep;
1147 struct usb_host_endpoint *ep;
1148 char ubuf[512], *dp, *end;
1149 unsigned long flags;
1150 struct urb *urb;
1151 int epnum, ret;
1152
1153 spin_lock_irqsave(&max3421_hcd->lock, flags);
1154 list_for_each_entry(max3421_ep, &max3421_hcd->ep_list, ep_list) {
1155 ep = max3421_ep->ep;
1156
1157 dp = ubuf;
1158 end = dp + sizeof(ubuf);
1159 *dp = '\0';
1160 list_for_each_entry(urb, &ep->urb_list, urb_list) {
1161 ret = snprintf(dp, end - dp, " %p(%d.%s %d/%d)", urb,
1162 usb_pipetype(urb->pipe),
1163 usb_urb_dir_in(urb) ? "IN" : "OUT",
1164 urb->actual_length,
1165 urb->transfer_buffer_length);
1166 if (ret < 0 || ret >= end - dp)
1167 break; /* error or buffer full */
1168 dp += ret;
1169 }
1170
1171 epnum = usb_endpoint_num(&ep->desc);
1172 pr_info("EP%0u %u lst %04u rtr %u nak %6u rxmt %u: %s\n",
1173 epnum, max3421_ep->pkt_state, max3421_ep->last_active,
1174 max3421_ep->retries, max3421_ep->naks,
1175 max3421_ep->retransmit, ubuf);
1176 }
1177 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1178 }
1179
1180 #endif /* DEBUG */
1181
1182 /* Return zero if no work was performed, 1 otherwise. */
1183 static int
max3421_handle_irqs(struct usb_hcd * hcd)1184 max3421_handle_irqs(struct usb_hcd *hcd)
1185 {
1186 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1187 u32 chg, old_port_status;
1188 unsigned long flags;
1189 u8 hirq;
1190
1191 /*
1192 * Read and ack pending interrupts (CPU must never
1193 * clear SNDBAV directly and RCVDAV must be cleared by
1194 * max3421_recv_data_available()!):
1195 */
1196 hirq = spi_rd8(hcd, MAX3421_REG_HIRQ);
1197 hirq &= max3421_hcd->hien;
1198 if (!hirq)
1199 return 0;
1200
1201 spi_wr8(hcd, MAX3421_REG_HIRQ,
1202 hirq & ~(BIT(MAX3421_HI_SNDBAV_BIT) |
1203 BIT(MAX3421_HI_RCVDAV_BIT)));
1204
1205 if (hirq & BIT(MAX3421_HI_FRAME_BIT)) {
1206 max3421_hcd->frame_number = ((max3421_hcd->frame_number + 1)
1207 & USB_MAX_FRAME_NUMBER);
1208 max3421_hcd->sched_pass = SCHED_PASS_PERIODIC;
1209 }
1210
1211 if (hirq & BIT(MAX3421_HI_RCVDAV_BIT))
1212 max3421_recv_data_available(hcd);
1213
1214 if (hirq & BIT(MAX3421_HI_HXFRDN_BIT))
1215 max3421_host_transfer_done(hcd);
1216
1217 if (hirq & BIT(MAX3421_HI_CONDET_BIT))
1218 max3421_detect_conn(hcd);
1219
1220 /*
1221 * Now process interrupts that may affect HCD state
1222 * other than the end-points:
1223 */
1224 spin_lock_irqsave(&max3421_hcd->lock, flags);
1225
1226 old_port_status = max3421_hcd->port_status;
1227 if (hirq & BIT(MAX3421_HI_BUSEVENT_BIT)) {
1228 if (max3421_hcd->port_status & USB_PORT_STAT_RESET) {
1229 /* BUSEVENT due to completion of Bus Reset */
1230 max3421_hcd->port_status &= ~USB_PORT_STAT_RESET;
1231 max3421_hcd->port_status |= USB_PORT_STAT_ENABLE;
1232 } else {
1233 /* BUSEVENT due to completion of Bus Resume */
1234 pr_info("%s: BUSEVENT Bus Resume Done\n", __func__);
1235 }
1236 }
1237 if (hirq & BIT(MAX3421_HI_RWU_BIT))
1238 pr_info("%s: RWU\n", __func__);
1239 if (hirq & BIT(MAX3421_HI_SUSDN_BIT))
1240 pr_info("%s: SUSDN\n", __func__);
1241
1242 chg = (old_port_status ^ max3421_hcd->port_status);
1243 max3421_hcd->port_status |= chg << 16;
1244
1245 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1246
1247 #ifdef DEBUG
1248 {
1249 static unsigned long last_time;
1250 char sbuf[16 * 16], *dp, *end;
1251 int i;
1252
1253 if (time_after(jiffies, last_time + 5*HZ)) {
1254 dp = sbuf;
1255 end = sbuf + sizeof(sbuf);
1256 *dp = '\0';
1257 for (i = 0; i < 16; ++i) {
1258 int ret = snprintf(dp, end - dp, " %lu",
1259 max3421_hcd->err_stat[i]);
1260 if (ret < 0 || ret >= end - dp)
1261 break; /* error or buffer full */
1262 dp += ret;
1263 }
1264 pr_info("%s: hrsl_stats %s\n", __func__, sbuf);
1265 memset(max3421_hcd->err_stat, 0,
1266 sizeof(max3421_hcd->err_stat));
1267 last_time = jiffies;
1268
1269 dump_eps(hcd);
1270 }
1271 }
1272 #endif
1273 return 1;
1274 }
1275
1276 static int
max3421_reset_hcd(struct usb_hcd * hcd)1277 max3421_reset_hcd(struct usb_hcd *hcd)
1278 {
1279 struct spi_device *spi = to_spi_device(hcd->self.controller);
1280 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1281 int timeout;
1282
1283 /* perform a chip reset and wait for OSCIRQ signal to appear: */
1284 spi_wr8(hcd, MAX3421_REG_USBCTL, BIT(MAX3421_USBCTL_CHIPRES_BIT));
1285 /* clear reset: */
1286 spi_wr8(hcd, MAX3421_REG_USBCTL, 0);
1287 timeout = 1000;
1288 while (1) {
1289 if (spi_rd8(hcd, MAX3421_REG_USBIRQ)
1290 & BIT(MAX3421_USBIRQ_OSCOKIRQ_BIT))
1291 break;
1292 if (--timeout < 0) {
1293 dev_err(&spi->dev,
1294 "timed out waiting for oscillator OK signal");
1295 return 1;
1296 }
1297 cond_resched();
1298 }
1299
1300 /*
1301 * Turn on host mode, automatic generation of SOF packets, and
1302 * enable pull-down registers on DM/DP:
1303 */
1304 max3421_hcd->mode = (BIT(MAX3421_MODE_HOST_BIT) |
1305 BIT(MAX3421_MODE_SOFKAENAB_BIT) |
1306 BIT(MAX3421_MODE_DMPULLDN_BIT) |
1307 BIT(MAX3421_MODE_DPPULLDN_BIT));
1308 spi_wr8(hcd, MAX3421_REG_MODE, max3421_hcd->mode);
1309
1310 /* reset frame-number: */
1311 max3421_hcd->frame_number = USB_MAX_FRAME_NUMBER;
1312 spi_wr8(hcd, MAX3421_REG_HCTL, BIT(MAX3421_HCTL_FRMRST_BIT));
1313
1314 /* sample the state of the D+ and D- lines */
1315 spi_wr8(hcd, MAX3421_REG_HCTL, BIT(MAX3421_HCTL_SAMPLEBUS_BIT));
1316 max3421_detect_conn(hcd);
1317
1318 /* enable frame, connection-detected, and bus-event interrupts: */
1319 max3421_hcd->hien = (BIT(MAX3421_HI_FRAME_BIT) |
1320 BIT(MAX3421_HI_CONDET_BIT) |
1321 BIT(MAX3421_HI_BUSEVENT_BIT));
1322 spi_wr8(hcd, MAX3421_REG_HIEN, max3421_hcd->hien);
1323
1324 /* enable interrupts: */
1325 spi_wr8(hcd, MAX3421_REG_CPUCTL, BIT(MAX3421_CPUCTL_IE_BIT));
1326 return 1;
1327 }
1328
1329 static int
max3421_urb_done(struct usb_hcd * hcd)1330 max3421_urb_done(struct usb_hcd *hcd)
1331 {
1332 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1333 unsigned long flags;
1334 struct urb *urb;
1335 int status;
1336
1337 status = max3421_hcd->urb_done;
1338 max3421_hcd->urb_done = 0;
1339 if (status > 0)
1340 status = 0;
1341 urb = max3421_hcd->curr_urb;
1342 if (urb) {
1343 /* save the old end-points toggles: */
1344 u8 hrsl = spi_rd8(hcd, MAX3421_REG_HRSL);
1345 int rcvtog = (hrsl >> MAX3421_HRSL_RCVTOGRD_BIT) & 1;
1346 int sndtog = (hrsl >> MAX3421_HRSL_SNDTOGRD_BIT) & 1;
1347 int epnum = usb_endpoint_num(&urb->ep->desc);
1348
1349 /* no locking: HCD (i.e., we) own toggles, don't we? */
1350 usb_settoggle(urb->dev, epnum, 0, rcvtog);
1351 usb_settoggle(urb->dev, epnum, 1, sndtog);
1352
1353 max3421_hcd->curr_urb = NULL;
1354 spin_lock_irqsave(&max3421_hcd->lock, flags);
1355 usb_hcd_unlink_urb_from_ep(hcd, urb);
1356 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1357
1358 /* must be called without the HCD spinlock: */
1359 usb_hcd_giveback_urb(hcd, urb, status);
1360 }
1361 return 1;
1362 }
1363
1364 static int
max3421_spi_thread(void * dev_id)1365 max3421_spi_thread(void *dev_id)
1366 {
1367 struct usb_hcd *hcd = dev_id;
1368 struct spi_device *spi = to_spi_device(hcd->self.controller);
1369 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1370 int i, i_worked = 1;
1371
1372 /* set full-duplex SPI mode, low-active interrupt pin: */
1373 spi_wr8(hcd, MAX3421_REG_PINCTL,
1374 (BIT(MAX3421_PINCTL_FDUPSPI_BIT) | /* full-duplex */
1375 BIT(MAX3421_PINCTL_INTLEVEL_BIT))); /* low-active irq */
1376
1377 while (!kthread_should_stop()) {
1378 max3421_hcd->rev = spi_rd8(hcd, MAX3421_REG_REVISION);
1379 if (max3421_hcd->rev == 0x12 || max3421_hcd->rev == 0x13)
1380 break;
1381 dev_err(&spi->dev, "bad rev 0x%02x", max3421_hcd->rev);
1382 msleep(10000);
1383 }
1384 dev_info(&spi->dev, "rev 0x%x, SPI clk %dHz, bpw %u, irq %d\n",
1385 max3421_hcd->rev, spi->max_speed_hz, spi->bits_per_word,
1386 spi->irq);
1387
1388 while (!kthread_should_stop()) {
1389 if (!i_worked) {
1390 /*
1391 * We'll be waiting for wakeups from the hard
1392 * interrupt handler, so now is a good time to
1393 * sync our hien with the chip:
1394 */
1395 spi_wr8(hcd, MAX3421_REG_HIEN, max3421_hcd->hien);
1396
1397 set_current_state(TASK_INTERRUPTIBLE);
1398 if (test_and_clear_bit(ENABLE_IRQ, &max3421_hcd->todo))
1399 enable_irq(spi->irq);
1400 schedule();
1401 __set_current_state(TASK_RUNNING);
1402 }
1403
1404 i_worked = 0;
1405
1406 if (max3421_hcd->urb_done)
1407 i_worked |= max3421_urb_done(hcd);
1408 else if (max3421_handle_irqs(hcd))
1409 i_worked = 1;
1410 else if (!max3421_hcd->curr_urb)
1411 i_worked |= max3421_select_and_start_urb(hcd);
1412
1413 if (test_and_clear_bit(RESET_HCD, &max3421_hcd->todo))
1414 /* reset the HCD: */
1415 i_worked |= max3421_reset_hcd(hcd);
1416 if (test_and_clear_bit(RESET_PORT, &max3421_hcd->todo)) {
1417 /* perform a USB bus reset: */
1418 spi_wr8(hcd, MAX3421_REG_HCTL,
1419 BIT(MAX3421_HCTL_BUSRST_BIT));
1420 i_worked = 1;
1421 }
1422 if (test_and_clear_bit(CHECK_UNLINK, &max3421_hcd->todo))
1423 i_worked |= max3421_check_unlink(hcd);
1424 if (test_and_clear_bit(IOPIN_UPDATE, &max3421_hcd->todo)) {
1425 /*
1426 * IOPINS1/IOPINS2 do not auto-increment, so we can't
1427 * use spi_wr_buf().
1428 */
1429 for (i = 0; i < ARRAY_SIZE(max3421_hcd->iopins); ++i) {
1430 u8 val = spi_rd8(hcd, MAX3421_REG_IOPINS1 + i);
1431
1432 val = ((val & 0xf0) |
1433 (max3421_hcd->iopins[i] & 0x0f));
1434 spi_wr8(hcd, MAX3421_REG_IOPINS1 + i, val);
1435 max3421_hcd->iopins[i] = val;
1436 }
1437 i_worked = 1;
1438 }
1439 }
1440 set_current_state(TASK_RUNNING);
1441 dev_info(&spi->dev, "SPI thread exiting");
1442 return 0;
1443 }
1444
1445 static int
max3421_reset_port(struct usb_hcd * hcd)1446 max3421_reset_port(struct usb_hcd *hcd)
1447 {
1448 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1449
1450 max3421_hcd->port_status &= ~(USB_PORT_STAT_ENABLE |
1451 USB_PORT_STAT_LOW_SPEED);
1452 max3421_hcd->port_status |= USB_PORT_STAT_RESET;
1453 set_bit(RESET_PORT, &max3421_hcd->todo);
1454 wake_up_process(max3421_hcd->spi_thread);
1455 return 0;
1456 }
1457
1458 static int
max3421_reset(struct usb_hcd * hcd)1459 max3421_reset(struct usb_hcd *hcd)
1460 {
1461 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1462
1463 hcd->self.sg_tablesize = 0;
1464 hcd->speed = HCD_USB2;
1465 hcd->self.root_hub->speed = USB_SPEED_FULL;
1466 set_bit(RESET_HCD, &max3421_hcd->todo);
1467 wake_up_process(max3421_hcd->spi_thread);
1468 return 0;
1469 }
1470
1471 static int
max3421_start(struct usb_hcd * hcd)1472 max3421_start(struct usb_hcd *hcd)
1473 {
1474 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1475
1476 spin_lock_init(&max3421_hcd->lock);
1477 max3421_hcd->rh_state = MAX3421_RH_RUNNING;
1478
1479 INIT_LIST_HEAD(&max3421_hcd->ep_list);
1480
1481 hcd->power_budget = POWER_BUDGET;
1482 hcd->state = HC_STATE_RUNNING;
1483 hcd->uses_new_polling = 1;
1484 return 0;
1485 }
1486
1487 static void
max3421_stop(struct usb_hcd * hcd)1488 max3421_stop(struct usb_hcd *hcd)
1489 {
1490 }
1491
1492 static int
max3421_urb_enqueue(struct usb_hcd * hcd,struct urb * urb,gfp_t mem_flags)1493 max3421_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flags)
1494 {
1495 struct spi_device *spi = to_spi_device(hcd->self.controller);
1496 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1497 struct max3421_ep *max3421_ep;
1498 unsigned long flags;
1499 int retval;
1500
1501 switch (usb_pipetype(urb->pipe)) {
1502 case PIPE_INTERRUPT:
1503 case PIPE_ISOCHRONOUS:
1504 if (urb->interval < 0) {
1505 dev_err(&spi->dev,
1506 "%s: interval=%d for intr-/iso-pipe; expected > 0\n",
1507 __func__, urb->interval);
1508 return -EINVAL;
1509 }
1510 break;
1511 default:
1512 break;
1513 }
1514
1515 spin_lock_irqsave(&max3421_hcd->lock, flags);
1516
1517 max3421_ep = urb->ep->hcpriv;
1518 if (!max3421_ep) {
1519 /* gets freed in max3421_endpoint_disable: */
1520 max3421_ep = kzalloc(sizeof(struct max3421_ep), GFP_ATOMIC);
1521 if (!max3421_ep) {
1522 retval = -ENOMEM;
1523 goto out;
1524 }
1525 max3421_ep->ep = urb->ep;
1526 max3421_ep->last_active = max3421_hcd->frame_number;
1527 urb->ep->hcpriv = max3421_ep;
1528
1529 list_add_tail(&max3421_ep->ep_list, &max3421_hcd->ep_list);
1530 }
1531
1532 retval = usb_hcd_link_urb_to_ep(hcd, urb);
1533 if (retval == 0) {
1534 /* Since we added to the queue, restart scheduling: */
1535 max3421_hcd->sched_pass = SCHED_PASS_PERIODIC;
1536 wake_up_process(max3421_hcd->spi_thread);
1537 }
1538
1539 out:
1540 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1541 return retval;
1542 }
1543
1544 static int
max3421_urb_dequeue(struct usb_hcd * hcd,struct urb * urb,int status)1545 max3421_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
1546 {
1547 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1548 unsigned long flags;
1549 int retval;
1550
1551 spin_lock_irqsave(&max3421_hcd->lock, flags);
1552
1553 /*
1554 * This will set urb->unlinked which in turn causes the entry
1555 * to be dropped at the next opportunity.
1556 */
1557 retval = usb_hcd_check_unlink_urb(hcd, urb, status);
1558 if (retval == 0) {
1559 set_bit(CHECK_UNLINK, &max3421_hcd->todo);
1560 wake_up_process(max3421_hcd->spi_thread);
1561 }
1562 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1563 return retval;
1564 }
1565
1566 static void
max3421_endpoint_disable(struct usb_hcd * hcd,struct usb_host_endpoint * ep)1567 max3421_endpoint_disable(struct usb_hcd *hcd, struct usb_host_endpoint *ep)
1568 {
1569 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1570 unsigned long flags;
1571
1572 spin_lock_irqsave(&max3421_hcd->lock, flags);
1573
1574 if (ep->hcpriv) {
1575 struct max3421_ep *max3421_ep = ep->hcpriv;
1576
1577 /* remove myself from the ep_list: */
1578 if (!list_empty(&max3421_ep->ep_list))
1579 list_del(&max3421_ep->ep_list);
1580 kfree(max3421_ep);
1581 ep->hcpriv = NULL;
1582 }
1583
1584 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1585 }
1586
1587 static int
max3421_get_frame_number(struct usb_hcd * hcd)1588 max3421_get_frame_number(struct usb_hcd *hcd)
1589 {
1590 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1591 return max3421_hcd->frame_number;
1592 }
1593
1594 /*
1595 * Should return a non-zero value when any port is undergoing a resume
1596 * transition while the root hub is suspended.
1597 */
1598 static int
max3421_hub_status_data(struct usb_hcd * hcd,char * buf)1599 max3421_hub_status_data(struct usb_hcd *hcd, char *buf)
1600 {
1601 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1602 unsigned long flags;
1603 int retval = 0;
1604
1605 spin_lock_irqsave(&max3421_hcd->lock, flags);
1606 if (!HCD_HW_ACCESSIBLE(hcd))
1607 goto done;
1608
1609 *buf = 0;
1610 if ((max3421_hcd->port_status & PORT_C_MASK) != 0) {
1611 *buf = (1 << 1); /* a hub over-current condition exists */
1612 dev_dbg(hcd->self.controller,
1613 "port status 0x%08x has changes\n",
1614 max3421_hcd->port_status);
1615 retval = 1;
1616 if (max3421_hcd->rh_state == MAX3421_RH_SUSPENDED)
1617 usb_hcd_resume_root_hub(hcd);
1618 }
1619 done:
1620 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1621 return retval;
1622 }
1623
1624 static inline void
hub_descriptor(struct usb_hub_descriptor * desc)1625 hub_descriptor(struct usb_hub_descriptor *desc)
1626 {
1627 memset(desc, 0, sizeof(*desc));
1628 /*
1629 * See Table 11-13: Hub Descriptor in USB 2.0 spec.
1630 */
1631 desc->bDescriptorType = USB_DT_HUB; /* hub descriptor */
1632 desc->bDescLength = 9;
1633 desc->wHubCharacteristics = cpu_to_le16(HUB_CHAR_INDV_PORT_LPSM |
1634 HUB_CHAR_COMMON_OCPM);
1635 desc->bNbrPorts = 1;
1636 }
1637
1638 /*
1639 * Set the MAX3421E general-purpose output with number PIN_NUMBER to
1640 * VALUE (0 or 1). PIN_NUMBER may be in the range from 1-8. For
1641 * any other value, this function acts as a no-op.
1642 */
1643 static void
max3421_gpout_set_value(struct usb_hcd * hcd,u8 pin_number,u8 value)1644 max3421_gpout_set_value(struct usb_hcd *hcd, u8 pin_number, u8 value)
1645 {
1646 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1647 u8 mask, idx;
1648
1649 --pin_number;
1650 if (pin_number >= MAX3421_GPOUT_COUNT)
1651 return;
1652
1653 mask = 1u << (pin_number % 4);
1654 idx = pin_number / 4;
1655
1656 if (value)
1657 max3421_hcd->iopins[idx] |= mask;
1658 else
1659 max3421_hcd->iopins[idx] &= ~mask;
1660 set_bit(IOPIN_UPDATE, &max3421_hcd->todo);
1661 wake_up_process(max3421_hcd->spi_thread);
1662 }
1663
1664 static int
max3421_hub_control(struct usb_hcd * hcd,u16 type_req,u16 value,u16 index,char * buf,u16 length)1665 max3421_hub_control(struct usb_hcd *hcd, u16 type_req, u16 value, u16 index,
1666 char *buf, u16 length)
1667 {
1668 struct spi_device *spi = to_spi_device(hcd->self.controller);
1669 struct max3421_hcd *max3421_hcd = hcd_to_max3421(hcd);
1670 struct max3421_hcd_platform_data *pdata;
1671 unsigned long flags;
1672 int retval = 0;
1673
1674 pdata = spi->dev.platform_data;
1675
1676 spin_lock_irqsave(&max3421_hcd->lock, flags);
1677
1678 switch (type_req) {
1679 case ClearHubFeature:
1680 break;
1681 case ClearPortFeature:
1682 switch (value) {
1683 case USB_PORT_FEAT_SUSPEND:
1684 break;
1685 case USB_PORT_FEAT_POWER:
1686 dev_dbg(hcd->self.controller, "power-off\n");
1687 max3421_gpout_set_value(hcd, pdata->vbus_gpout,
1688 !pdata->vbus_active_level);
1689 fallthrough;
1690 default:
1691 max3421_hcd->port_status &= ~(1 << value);
1692 }
1693 break;
1694 case GetHubDescriptor:
1695 hub_descriptor((struct usb_hub_descriptor *) buf);
1696 break;
1697
1698 case DeviceRequest | USB_REQ_GET_DESCRIPTOR:
1699 case GetPortErrorCount:
1700 case SetHubDepth:
1701 /* USB3 only */
1702 goto error;
1703
1704 case GetHubStatus:
1705 *(__le32 *) buf = cpu_to_le32(0);
1706 break;
1707
1708 case GetPortStatus:
1709 if (index != 1) {
1710 retval = -EPIPE;
1711 goto error;
1712 }
1713 ((__le16 *) buf)[0] = cpu_to_le16(max3421_hcd->port_status);
1714 ((__le16 *) buf)[1] =
1715 cpu_to_le16(max3421_hcd->port_status >> 16);
1716 break;
1717
1718 case SetHubFeature:
1719 retval = -EPIPE;
1720 break;
1721
1722 case SetPortFeature:
1723 switch (value) {
1724 case USB_PORT_FEAT_LINK_STATE:
1725 case USB_PORT_FEAT_U1_TIMEOUT:
1726 case USB_PORT_FEAT_U2_TIMEOUT:
1727 case USB_PORT_FEAT_BH_PORT_RESET:
1728 goto error;
1729 case USB_PORT_FEAT_SUSPEND:
1730 if (max3421_hcd->active)
1731 max3421_hcd->port_status |=
1732 USB_PORT_STAT_SUSPEND;
1733 break;
1734 case USB_PORT_FEAT_POWER:
1735 dev_dbg(hcd->self.controller, "power-on\n");
1736 max3421_hcd->port_status |= USB_PORT_STAT_POWER;
1737 max3421_gpout_set_value(hcd, pdata->vbus_gpout,
1738 pdata->vbus_active_level);
1739 break;
1740 case USB_PORT_FEAT_RESET:
1741 max3421_reset_port(hcd);
1742 fallthrough;
1743 default:
1744 if ((max3421_hcd->port_status & USB_PORT_STAT_POWER)
1745 != 0)
1746 max3421_hcd->port_status |= (1 << value);
1747 }
1748 break;
1749
1750 default:
1751 dev_dbg(hcd->self.controller,
1752 "hub control req%04x v%04x i%04x l%d\n",
1753 type_req, value, index, length);
1754 error: /* "protocol stall" on error */
1755 retval = -EPIPE;
1756 }
1757
1758 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1759 return retval;
1760 }
1761
1762 static int
max3421_bus_suspend(struct usb_hcd * hcd)1763 max3421_bus_suspend(struct usb_hcd *hcd)
1764 {
1765 return -1;
1766 }
1767
1768 static int
max3421_bus_resume(struct usb_hcd * hcd)1769 max3421_bus_resume(struct usb_hcd *hcd)
1770 {
1771 return -1;
1772 }
1773
1774 static const struct hc_driver max3421_hcd_desc = {
1775 .description = "max3421",
1776 .product_desc = DRIVER_DESC,
1777 .hcd_priv_size = sizeof(struct max3421_hcd),
1778 .flags = HCD_USB11,
1779 .reset = max3421_reset,
1780 .start = max3421_start,
1781 .stop = max3421_stop,
1782 .get_frame_number = max3421_get_frame_number,
1783 .urb_enqueue = max3421_urb_enqueue,
1784 .urb_dequeue = max3421_urb_dequeue,
1785 .endpoint_disable = max3421_endpoint_disable,
1786 .hub_status_data = max3421_hub_status_data,
1787 .hub_control = max3421_hub_control,
1788 .bus_suspend = max3421_bus_suspend,
1789 .bus_resume = max3421_bus_resume,
1790 };
1791
1792 static int
max3421_of_vbus_en_pin(struct device * dev,struct max3421_hcd_platform_data * pdata)1793 max3421_of_vbus_en_pin(struct device *dev, struct max3421_hcd_platform_data *pdata)
1794 {
1795 int retval;
1796 uint32_t value[2];
1797
1798 if (!pdata)
1799 return -EINVAL;
1800
1801 retval = of_property_read_u32_array(dev->of_node, "maxim,vbus-en-pin", value, 2);
1802 if (retval) {
1803 dev_err(dev, "device tree node property 'maxim,vbus-en-pin' is missing\n");
1804 return retval;
1805 }
1806 dev_info(dev, "property 'maxim,vbus-en-pin' value is <%d %d>\n", value[0], value[1]);
1807
1808 pdata->vbus_gpout = value[0];
1809 pdata->vbus_active_level = value[1];
1810
1811 return 0;
1812 }
1813
1814 static int
max3421_probe(struct spi_device * spi)1815 max3421_probe(struct spi_device *spi)
1816 {
1817 struct device *dev = &spi->dev;
1818 struct max3421_hcd *max3421_hcd;
1819 struct usb_hcd *hcd = NULL;
1820 struct max3421_hcd_platform_data *pdata = NULL;
1821 int retval;
1822
1823 if (spi_setup(spi) < 0) {
1824 dev_err(&spi->dev, "Unable to setup SPI bus");
1825 return -EFAULT;
1826 }
1827
1828 if (!spi->irq) {
1829 dev_err(dev, "Failed to get SPI IRQ");
1830 return -EFAULT;
1831 }
1832
1833 if (IS_ENABLED(CONFIG_OF) && dev->of_node) {
1834 pdata = devm_kzalloc(&spi->dev, sizeof(*pdata), GFP_KERNEL);
1835 if (!pdata) {
1836 retval = -ENOMEM;
1837 goto error;
1838 }
1839 retval = max3421_of_vbus_en_pin(dev, pdata);
1840 if (retval)
1841 goto error;
1842
1843 spi->dev.platform_data = pdata;
1844 }
1845
1846 pdata = spi->dev.platform_data;
1847 if (!pdata) {
1848 dev_err(&spi->dev, "driver configuration data is not provided\n");
1849 retval = -EFAULT;
1850 goto error;
1851 }
1852 if (pdata->vbus_active_level > 1) {
1853 dev_err(&spi->dev, "vbus active level value %d is out of range (0/1)\n", pdata->vbus_active_level);
1854 retval = -EINVAL;
1855 goto error;
1856 }
1857 if (pdata->vbus_gpout < 1 || pdata->vbus_gpout > MAX3421_GPOUT_COUNT) {
1858 dev_err(&spi->dev, "vbus gpout value %d is out of range (1..8)\n", pdata->vbus_gpout);
1859 retval = -EINVAL;
1860 goto error;
1861 }
1862
1863 retval = -ENOMEM;
1864 hcd = usb_create_hcd(&max3421_hcd_desc, &spi->dev,
1865 dev_name(&spi->dev));
1866 if (!hcd) {
1867 dev_err(&spi->dev, "failed to create HCD structure\n");
1868 goto error;
1869 }
1870 set_bit(HCD_FLAG_POLL_RH, &hcd->flags);
1871 max3421_hcd = hcd_to_max3421(hcd);
1872 INIT_LIST_HEAD(&max3421_hcd->ep_list);
1873 spi_set_drvdata(spi, max3421_hcd);
1874
1875 max3421_hcd->tx = kmalloc(sizeof(*max3421_hcd->tx), GFP_KERNEL);
1876 if (!max3421_hcd->tx)
1877 goto error;
1878 max3421_hcd->rx = kmalloc(sizeof(*max3421_hcd->rx), GFP_KERNEL);
1879 if (!max3421_hcd->rx)
1880 goto error;
1881
1882 max3421_hcd->spi_thread = kthread_run(max3421_spi_thread, hcd,
1883 "max3421_spi_thread");
1884 if (max3421_hcd->spi_thread == ERR_PTR(-ENOMEM)) {
1885 dev_err(&spi->dev,
1886 "failed to create SPI thread (out of memory)\n");
1887 goto error;
1888 }
1889
1890 retval = usb_add_hcd(hcd, 0, 0);
1891 if (retval) {
1892 dev_err(&spi->dev, "failed to add HCD\n");
1893 goto error;
1894 }
1895
1896 retval = request_irq(spi->irq, max3421_irq_handler,
1897 IRQF_TRIGGER_LOW, "max3421", hcd);
1898 if (retval < 0) {
1899 dev_err(&spi->dev, "failed to request irq %d\n", spi->irq);
1900 goto error;
1901 }
1902 return 0;
1903
1904 error:
1905 if (IS_ENABLED(CONFIG_OF) && dev->of_node && pdata) {
1906 devm_kfree(&spi->dev, pdata);
1907 spi->dev.platform_data = NULL;
1908 }
1909
1910 if (hcd) {
1911 kfree(max3421_hcd->tx);
1912 kfree(max3421_hcd->rx);
1913 if (max3421_hcd->spi_thread)
1914 kthread_stop(max3421_hcd->spi_thread);
1915 usb_put_hcd(hcd);
1916 }
1917 return retval;
1918 }
1919
1920 static void
max3421_remove(struct spi_device * spi)1921 max3421_remove(struct spi_device *spi)
1922 {
1923 struct max3421_hcd *max3421_hcd;
1924 struct usb_hcd *hcd;
1925 unsigned long flags;
1926
1927 max3421_hcd = spi_get_drvdata(spi);
1928 hcd = max3421_to_hcd(max3421_hcd);
1929
1930 usb_remove_hcd(hcd);
1931
1932 spin_lock_irqsave(&max3421_hcd->lock, flags);
1933
1934 kthread_stop(max3421_hcd->spi_thread);
1935
1936 spin_unlock_irqrestore(&max3421_hcd->lock, flags);
1937
1938 free_irq(spi->irq, hcd);
1939
1940 usb_put_hcd(hcd);
1941 }
1942
1943 static const struct of_device_id max3421_of_match_table[] = {
1944 { .compatible = "maxim,max3421", },
1945 {},
1946 };
1947 MODULE_DEVICE_TABLE(of, max3421_of_match_table);
1948
1949 static struct spi_driver max3421_driver = {
1950 .probe = max3421_probe,
1951 .remove = max3421_remove,
1952 .driver = {
1953 .name = "max3421-hcd",
1954 .of_match_table = max3421_of_match_table,
1955 },
1956 };
1957
1958 module_spi_driver(max3421_driver);
1959
1960 MODULE_DESCRIPTION(DRIVER_DESC);
1961 MODULE_AUTHOR("David Mosberger <davidm@egauge.net>");
1962 MODULE_LICENSE("GPL");
1963
