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eventfd/kaio integration fix
[linux-2.6.22.y-op.git] / drivers / spi / mpc52xx_psc_spi.c
blob11f36bef3057493a6c7b0c3e79e5f270f220a601
1 /*
2 * MPC52xx SPC in SPI mode driver.
3 *
4 * Maintainer: Dragos Carp
5 *
6 * Copyright (C) 2006 TOPTICA Photonics AG.
7 *
8 * This program is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License as published by the
10 * Free Software Foundation; either version 2 of the License, or (at your
11 * option) any later version.
12 */
13
14 #include <linux/module.h>
15 #include <linux/init.h>
16 #include <linux/errno.h>
17 #include <linux/interrupt.h>
18
19 #if defined(CONFIG_PPC_MERGE)
20 #include <asm/of_platform.h>
21 #else
22 #include <linux/platform_device.h>
23 #endif
24
25 #include <linux/workqueue.h>
26 #include <linux/completion.h>
27 #include <linux/io.h>
28 #include <linux/delay.h>
29 #include <linux/spi/spi.h>
30 #include <linux/fsl_devices.h>
31
32 #include <asm/mpc52xx.h>
33 #include <asm/mpc52xx_psc.h>
34
35 #define MCLK 20000000 /* PSC port MClk in hz */
36
37 struct mpc52xx_psc_spi {
38 /* fsl_spi_platform data */
39 void (*activate_cs)(u8, u8);
40 void (*deactivate_cs)(u8, u8);
41 u32 sysclk;
42
43 /* driver internal data */
44 struct mpc52xx_psc __iomem *psc;
45 unsigned int irq;
46 u8 bits_per_word;
47 u8 busy;
48
49 struct workqueue_struct *workqueue;
50 struct work_struct work;
51
52 struct list_head queue;
53 spinlock_t lock;
54
55 struct completion done;
56 };
57
58 /* controller state */
59 struct mpc52xx_psc_spi_cs {
60 int bits_per_word;
61 int speed_hz;
62 };
63
64 /* set clock freq, clock ramp, bits per work
65 * if t is NULL then reset the values to the default values
66 */
67 static int mpc52xx_psc_spi_transfer_setup(struct spi_device *spi,
68 struct spi_transfer *t)
69 {
70 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
71
72 cs->speed_hz = (t && t->speed_hz)
73 ? t->speed_hz : spi->max_speed_hz;
74 cs->bits_per_word = (t && t->bits_per_word)
75 ? t->bits_per_word : spi->bits_per_word;
76 cs->bits_per_word = ((cs->bits_per_word + 7) / 8) * 8;
77 return 0;
78 }
79
80 static void mpc52xx_psc_spi_activate_cs(struct spi_device *spi)
81 {
82 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
83 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
84 struct mpc52xx_psc __iomem *psc = mps->psc;
85 u32 sicr;
86 u16 ccr;
87
88 sicr = in_be32(&psc->sicr);
89
90 /* Set clock phase and polarity */
91 if (spi->mode & SPI_CPHA)
92 sicr |= 0x00001000;
93 else
94 sicr &= ~0x00001000;
95 if (spi->mode & SPI_CPOL)
96 sicr |= 0x00002000;
97 else
98 sicr &= ~0x00002000;
99
100 if (spi->mode & SPI_LSB_FIRST)
101 sicr |= 0x10000000;
102 else
103 sicr &= ~0x10000000;
104 out_be32(&psc->sicr, sicr);
105
106 /* Set clock frequency and bits per word
107 * Because psc->ccr is defined as 16bit register instead of 32bit
108 * just set the lower byte of BitClkDiv
109 */
110 ccr = in_be16(&psc->ccr);
111 ccr &= 0xFF00;
112 if (cs->speed_hz)
113 ccr |= (MCLK / cs->speed_hz - 1) & 0xFF;
114 else /* by default SPI Clk 1MHz */
115 ccr |= (MCLK / 1000000 - 1) & 0xFF;
116 out_be16(&psc->ccr, ccr);
117 mps->bits_per_word = cs->bits_per_word;
118
119 if (mps->activate_cs)
120 mps->activate_cs(spi->chip_select,
121 (spi->mode & SPI_CS_HIGH) ? 1 : 0);
122 }
123
124 static void mpc52xx_psc_spi_deactivate_cs(struct spi_device *spi)
125 {
126 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
127
128 if (mps->deactivate_cs)
129 mps->deactivate_cs(spi->chip_select,
130 (spi->mode & SPI_CS_HIGH) ? 1 : 0);
131 }
132
133 #define MPC52xx_PSC_BUFSIZE (MPC52xx_PSC_RFNUM_MASK + 1)
134 /* wake up when 80% fifo full */
135 #define MPC52xx_PSC_RFALARM (MPC52xx_PSC_BUFSIZE * 20 / 100)
136
137 static int mpc52xx_psc_spi_transfer_rxtx(struct spi_device *spi,
138 struct spi_transfer *t)
139 {
140 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
141 struct mpc52xx_psc __iomem *psc = mps->psc;
142 unsigned rb = 0; /* number of bytes receieved */
143 unsigned sb = 0; /* number of bytes sent */
144 unsigned char *rx_buf = (unsigned char *)t->rx_buf;
145 unsigned char *tx_buf = (unsigned char *)t->tx_buf;
146 unsigned rfalarm;
147 unsigned send_at_once = MPC52xx_PSC_BUFSIZE;
148 unsigned recv_at_once;
149 unsigned bpw = mps->bits_per_word / 8;
150
151 if (!t->tx_buf && !t->rx_buf && t->len)
152 return -EINVAL;
153
154 /* enable transmiter/receiver */
155 out_8(&psc->command, MPC52xx_PSC_TX_ENABLE | MPC52xx_PSC_RX_ENABLE);
156 while (rb < t->len) {
157 if (t->len - rb > MPC52xx_PSC_BUFSIZE) {
158 rfalarm = MPC52xx_PSC_RFALARM;
159 } else {
160 send_at_once = t->len - sb;
161 rfalarm = MPC52xx_PSC_BUFSIZE - (t->len - rb);
162 }
163
164 dev_dbg(&spi->dev, "send %d bytes...\n", send_at_once);
165 if (tx_buf) {
166 for (; send_at_once; sb++, send_at_once--) {
167 /* set EOF flag */
168 if (mps->bits_per_word
169 && (sb + 1) % bpw == 0)
170 out_8(&psc->ircr2, 0x01);
171 out_8(&psc->mpc52xx_psc_buffer_8, tx_buf[sb]);
172 }
173 } else {
174 for (; send_at_once; sb++, send_at_once--) {
175 /* set EOF flag */
176 if (mps->bits_per_word
177 && ((sb + 1) % bpw) == 0)
178 out_8(&psc->ircr2, 0x01);
179 out_8(&psc->mpc52xx_psc_buffer_8, 0);
180 }
181 }
182
183
184 /* enable interupts and wait for wake up
185 * if just one byte is expected the Rx FIFO genererates no
186 * FFULL interrupt, so activate the RxRDY interrupt
187 */
188 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
189 if (t->len - rb == 1) {
190 out_8(&psc->mode, 0);
191 } else {
192 out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
193 out_be16(&psc->rfalarm, rfalarm);
194 }
195 out_be16(&psc->mpc52xx_psc_imr, MPC52xx_PSC_IMR_RXRDY);
196 wait_for_completion(&mps->done);
197 recv_at_once = in_be16(&psc->rfnum);
198 dev_dbg(&spi->dev, "%d bytes received\n", recv_at_once);
199
200 send_at_once = recv_at_once;
201 if (rx_buf) {
202 for (; recv_at_once; rb++, recv_at_once--)
203 rx_buf[rb] = in_8(&psc->mpc52xx_psc_buffer_8);
204 } else {
205 for (; recv_at_once; rb++, recv_at_once--)
206 in_8(&psc->mpc52xx_psc_buffer_8);
207 }
208 }
209 /* disable transmiter/receiver */
210 out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
211
212 return 0;
213 }
214
215 static void mpc52xx_psc_spi_work(struct work_struct *work)
216 {
217 struct mpc52xx_psc_spi *mps =
218 container_of(work, struct mpc52xx_psc_spi, work);
219
220 spin_lock_irq(&mps->lock);
221 mps->busy = 1;
222 while (!list_empty(&mps->queue)) {
223 struct spi_message *m;
224 struct spi_device *spi;
225 struct spi_transfer *t = NULL;
226 unsigned cs_change;
227 int status;
228
229 m = container_of(mps->queue.next, struct spi_message, queue);
230 list_del_init(&m->queue);
231 spin_unlock_irq(&mps->lock);
232
233 spi = m->spi;
234 cs_change = 1;
235 status = 0;
236 list_for_each_entry (t, &m->transfers, transfer_list) {
237 if (t->bits_per_word || t->speed_hz) {
238 status = mpc52xx_psc_spi_transfer_setup(spi, t);
239 if (status < 0)
240 break;
241 }
242
243 if (cs_change)
244 mpc52xx_psc_spi_activate_cs(spi);
245 cs_change = t->cs_change;
246
247 status = mpc52xx_psc_spi_transfer_rxtx(spi, t);
248 if (status)
249 break;
250 m->actual_length += t->len;
251
252 if (t->delay_usecs)
253 udelay(t->delay_usecs);
254
255 if (cs_change)
256 mpc52xx_psc_spi_deactivate_cs(spi);
257 }
258
259 m->status = status;
260 m->complete(m->context);
261
262 if (status || !cs_change)
263 mpc52xx_psc_spi_deactivate_cs(spi);
264
265 mpc52xx_psc_spi_transfer_setup(spi, NULL);
266
267 spin_lock_irq(&mps->lock);
268 }
269 mps->busy = 0;
270 spin_unlock_irq(&mps->lock);
271 }
272
273 static int mpc52xx_psc_spi_setup(struct spi_device *spi)
274 {
275 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
276 struct mpc52xx_psc_spi_cs *cs = spi->controller_state;
277 unsigned long flags;
278
279 if (spi->bits_per_word%8)
280 return -EINVAL;
281
282 if (!cs) {
283 cs = kzalloc(sizeof *cs, GFP_KERNEL);
284 if (!cs)
285 return -ENOMEM;
286 spi->controller_state = cs;
287 }
288
289 cs->bits_per_word = spi->bits_per_word;
290 cs->speed_hz = spi->max_speed_hz;
291
292 spin_lock_irqsave(&mps->lock, flags);
293 if (!mps->busy)
294 mpc52xx_psc_spi_deactivate_cs(spi);
295 spin_unlock_irqrestore(&mps->lock, flags);
296
297 return 0;
298 }
299
300 static int mpc52xx_psc_spi_transfer(struct spi_device *spi,
301 struct spi_message *m)
302 {
303 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(spi->master);
304 unsigned long flags;
305
306 m->actual_length = 0;
307 m->status = -EINPROGRESS;
308
309 spin_lock_irqsave(&mps->lock, flags);
310 list_add_tail(&m->queue, &mps->queue);
311 queue_work(mps->workqueue, &mps->work);
312 spin_unlock_irqrestore(&mps->lock, flags);
313
314 return 0;
315 }
316
317 static void mpc52xx_psc_spi_cleanup(struct spi_device *spi)
318 {
319 kfree(spi->controller_state);
320 }
321
322 static int mpc52xx_psc_spi_port_config(int psc_id, struct mpc52xx_psc_spi *mps)
323 {
324 struct mpc52xx_cdm __iomem *cdm;
325 struct mpc52xx_gpio __iomem *gpio;
326 struct mpc52xx_psc __iomem *psc = mps->psc;
327 u32 ul;
328 u32 mclken_div;
329 int ret = 0;
330
331 #if defined(CONFIG_PPC_MERGE)
332 cdm = mpc52xx_find_and_map("mpc5200-cdm");
333 gpio = mpc52xx_find_and_map("mpc5200-gpio");
334 #else
335 cdm = ioremap(MPC52xx_PA(MPC52xx_CDM_OFFSET), MPC52xx_CDM_SIZE);
336 gpio = ioremap(MPC52xx_PA(MPC52xx_GPIO_OFFSET), MPC52xx_GPIO_SIZE);
337 #endif
338 if (!cdm || !gpio) {
339 printk(KERN_ERR "Error mapping CDM/GPIO\n");
340 ret = -EFAULT;
341 goto unmap_regs;
342 }
343
344 /* default sysclk is 512MHz */
345 mclken_div = 0x8000 |
346 (((mps->sysclk ? mps->sysclk : 512000000) / MCLK) & 0x1FF);
347
348 switch (psc_id) {
349 case 1:
350 ul = in_be32(&gpio->port_config);
351 ul &= 0xFFFFFFF8;
352 ul |= 0x00000006;
353 out_be32(&gpio->port_config, ul);
354 out_be16(&cdm->mclken_div_psc1, mclken_div);
355 ul = in_be32(&cdm->clk_enables);
356 ul |= 0x00000020;
357 out_be32(&cdm->clk_enables, ul);
358 break;
359 case 2:
360 ul = in_be32(&gpio->port_config);
361 ul &= 0xFFFFFF8F;
362 ul |= 0x00000060;
363 out_be32(&gpio->port_config, ul);
364 out_be16(&cdm->mclken_div_psc2, mclken_div);
365 ul = in_be32(&cdm->clk_enables);
366 ul |= 0x00000040;
367 out_be32(&cdm->clk_enables, ul);
368 break;
369 case 3:
370 ul = in_be32(&gpio->port_config);
371 ul &= 0xFFFFF0FF;
372 ul |= 0x00000600;
373 out_be32(&gpio->port_config, ul);
374 out_be16(&cdm->mclken_div_psc3, mclken_div);
375 ul = in_be32(&cdm->clk_enables);
376 ul |= 0x00000080;
377 out_be32(&cdm->clk_enables, ul);
378 break;
379 case 6:
380 ul = in_be32(&gpio->port_config);
381 ul &= 0xFF8FFFFF;
382 ul |= 0x00700000;
383 out_be32(&gpio->port_config, ul);
384 out_be16(&cdm->mclken_div_psc6, mclken_div);
385 ul = in_be32(&cdm->clk_enables);
386 ul |= 0x00000010;
387 out_be32(&cdm->clk_enables, ul);
388 break;
389 default:
390 ret = -EINVAL;
391 goto unmap_regs;
392 }
393
394 /* Reset the PSC into a known state */
395 out_8(&psc->command, MPC52xx_PSC_RST_RX);
396 out_8(&psc->command, MPC52xx_PSC_RST_TX);
397 out_8(&psc->command, MPC52xx_PSC_TX_DISABLE | MPC52xx_PSC_RX_DISABLE);
398
399 /* Disable interrupts, interrupts are based on alarm level */
400 out_be16(&psc->mpc52xx_psc_imr, 0);
401 out_8(&psc->command, MPC52xx_PSC_SEL_MODE_REG_1);
402 out_8(&psc->rfcntl, 0);
403 out_8(&psc->mode, MPC52xx_PSC_MODE_FFULL);
404
405 /* Configure 8bit codec mode as a SPI master and use EOF flags */
406 /* SICR_SIM_CODEC8|SICR_GENCLK|SICR_SPI|SICR_MSTR|SICR_USEEOF */
407 out_be32(&psc->sicr, 0x0180C800);
408 out_be16(&psc->ccr, 0x070F); /* by default SPI Clk 1MHz */
409
410 /* Set 2ms DTL delay */
411 out_8(&psc->ctur, 0x00);
412 out_8(&psc->ctlr, 0x84);
413
414 mps->bits_per_word = 8;
415
416 unmap_regs:
417 if (cdm)
418 iounmap(cdm);
419 if (gpio)
420 iounmap(gpio);
421
422 return ret;
423 }
424
425 static irqreturn_t mpc52xx_psc_spi_isr(int irq, void *dev_id)
426 {
427 struct mpc52xx_psc_spi *mps = (struct mpc52xx_psc_spi *)dev_id;
428 struct mpc52xx_psc __iomem *psc = mps->psc;
429
430 /* disable interrupt and wake up the work queue */
431 if (in_be16(&psc->mpc52xx_psc_isr) & MPC52xx_PSC_IMR_RXRDY) {
432 out_be16(&psc->mpc52xx_psc_imr, 0);
433 complete(&mps->done);
434 return IRQ_HANDLED;
435 }
436 return IRQ_NONE;
437 }
438
439 /* bus_num is used only for the case dev->platform_data == NULL */
440 static int __init mpc52xx_psc_spi_do_probe(struct device *dev, u32 regaddr,
441 u32 size, unsigned int irq, s16 bus_num)
442 {
443 struct fsl_spi_platform_data *pdata = dev->platform_data;
444 struct mpc52xx_psc_spi *mps;
445 struct spi_master *master;
446 int ret;
447
448 master = spi_alloc_master(dev, sizeof *mps);
449 if (master == NULL)
450 return -ENOMEM;
451
452 dev_set_drvdata(dev, master);
453 mps = spi_master_get_devdata(master);
454
455 mps->irq = irq;
456 if (pdata == NULL) {
457 dev_warn(dev, "probe called without platform data, no "
458 "(de)activate_cs function will be called\n");
459 mps->activate_cs = NULL;
460 mps->deactivate_cs = NULL;
461 mps->sysclk = 0;
462 master->bus_num = bus_num;
463 master->num_chipselect = 255;
464 } else {
465 mps->activate_cs = pdata->activate_cs;
466 mps->deactivate_cs = pdata->deactivate_cs;
467 mps->sysclk = pdata->sysclk;
468 master->bus_num = pdata->bus_num;
469 master->num_chipselect = pdata->max_chipselect;
470 }
471 master->setup = mpc52xx_psc_spi_setup;
472 master->transfer = mpc52xx_psc_spi_transfer;
473 master->cleanup = mpc52xx_psc_spi_cleanup;
474
475 mps->psc = ioremap(regaddr, size);
476 if (!mps->psc) {
477 dev_err(dev, "could not ioremap I/O port range\n");
478 ret = -EFAULT;
479 goto free_master;
480 }
481
482 ret = request_irq(mps->irq, mpc52xx_psc_spi_isr, 0, "mpc52xx-psc-spi",
483 mps);
484 if (ret)
485 goto free_master;
486
487 ret = mpc52xx_psc_spi_port_config(master->bus_num, mps);
488 if (ret < 0)
489 goto free_irq;
490
491 spin_lock_init(&mps->lock);
492 init_completion(&mps->done);
493 INIT_WORK(&mps->work, mpc52xx_psc_spi_work);
494 INIT_LIST_HEAD(&mps->queue);
495
496 mps->workqueue = create_singlethread_workqueue(
497 master->cdev.dev->bus_id);
498 if (mps->workqueue == NULL) {
499 ret = -EBUSY;
500 goto free_irq;
501 }
502
503 ret = spi_register_master(master);
504 if (ret < 0)
505 goto unreg_master;
506
507 return ret;
508
509 unreg_master:
510 destroy_workqueue(mps->workqueue);
511 free_irq:
512 free_irq(mps->irq, mps);
513 free_master:
514 if (mps->psc)
515 iounmap(mps->psc);
516 spi_master_put(master);
517
518 return ret;
519 }
520
521 static int __exit mpc52xx_psc_spi_do_remove(struct device *dev)
522 {
523 struct spi_master *master = dev_get_drvdata(dev);
524 struct mpc52xx_psc_spi *mps = spi_master_get_devdata(master);
525
526 flush_workqueue(mps->workqueue);
527 destroy_workqueue(mps->workqueue);
528 spi_unregister_master(master);
529 free_irq(mps->irq, mps);
530 if (mps->psc)
531 iounmap(mps->psc);
532
533 return 0;
534 }
535
536 #if !defined(CONFIG_PPC_MERGE)
537 static int __init mpc52xx_psc_spi_probe(struct platform_device *dev)
538 {
539 switch(dev->id) {
540 case 1:
541 case 2:
542 case 3:
543 case 6:
544 return mpc52xx_psc_spi_do_probe(&dev->dev,
545 MPC52xx_PA(MPC52xx_PSCx_OFFSET(dev->id)),
546 MPC52xx_PSC_SIZE, platform_get_irq(dev, 0), dev->id);
547 default:
548 return -EINVAL;
549 }
550 }
551
552 static int __exit mpc52xx_psc_spi_remove(struct platform_device *dev)
553 {
554 return mpc52xx_psc_spi_do_remove(&dev->dev);
555 }
556
557 static struct platform_driver mpc52xx_psc_spi_platform_driver = {
558 .remove = __exit_p(mpc52xx_psc_spi_remove),
559 .driver = {
560 .name = "mpc52xx-psc-spi",
561 .owner = THIS_MODULE,
562 },
563 };
564
565 static int __init mpc52xx_psc_spi_init(void)
566 {
567 return platform_driver_probe(&mpc52xx_psc_spi_platform_driver,
568 mpc52xx_psc_spi_probe);
569 }
570 module_init(mpc52xx_psc_spi_init);
571
572 static void __exit mpc52xx_psc_spi_exit(void)
573 {
574 platform_driver_unregister(&mpc52xx_psc_spi_platform_driver);
575 }
576 module_exit(mpc52xx_psc_spi_exit);
577
578 #else /* defined(CONFIG_PPC_MERGE) */
579
580 static int __init mpc52xx_psc_spi_of_probe(struct of_device *op,
581 const struct of_device_id *match)
582 {
583 const u32 *regaddr_p;
584 u64 regaddr64, size64;
585 s16 id = -1;
586
587 regaddr_p = of_get_address(op->node, 0, &size64, NULL);
588 if (!regaddr_p) {
589 printk(KERN_ERR "Invalid PSC address\n");
590 return -EINVAL;
591 }
592 regaddr64 = of_translate_address(op->node, regaddr_p);
593
594 /* get PSC id (1..6, used by port_config) */
595 if (op->dev.platform_data == NULL) {
596 const u32 *psc_nump;
597
598 psc_nump = of_get_property(op->node, "cell-index", NULL);
599 if (!psc_nump || *psc_nump > 5) {
600 printk(KERN_ERR "mpc52xx_psc_spi: Device node %s has invalid "
601 "cell-index property\n", op->node->full_name);
602 return -EINVAL;
603 }
604 id = *psc_nump + 1;
605 }
606
607 return mpc52xx_psc_spi_do_probe(&op->dev, (u32)regaddr64, (u32)size64,
608 irq_of_parse_and_map(op->node, 0), id);
609 }
610
611 static int __exit mpc52xx_psc_spi_of_remove(struct of_device *op)
612 {
613 return mpc52xx_psc_spi_do_remove(&op->dev);
614 }
615
616 static struct of_device_id mpc52xx_psc_spi_of_match[] = {
617 { .type = "spi", .compatible = "mpc5200-psc-spi", },
618 {},
619 };
620
621 MODULE_DEVICE_TABLE(of, mpc52xx_psc_spi_of_match);
622
623 static struct of_platform_driver mpc52xx_psc_spi_of_driver = {
624 .owner = THIS_MODULE,
625 .name = "mpc52xx-psc-spi",
626 .match_table = mpc52xx_psc_spi_of_match,
627 .probe = mpc52xx_psc_spi_of_probe,
628 .remove = __exit_p(mpc52xx_psc_spi_of_remove),
629 .driver = {
630 .name = "mpc52xx-psc-spi",
631 .owner = THIS_MODULE,
632 },
633 };
634
635 static int __init mpc52xx_psc_spi_init(void)
636 {
637 return of_register_platform_driver(&mpc52xx_psc_spi_of_driver);
638 }
639 module_init(mpc52xx_psc_spi_init);
640
641 static void __exit mpc52xx_psc_spi_exit(void)
642 {
643 of_unregister_platform_driver(&mpc52xx_psc_spi_of_driver);
644 }
645 module_exit(mpc52xx_psc_spi_exit);
646
647 #endif /* defined(CONFIG_PPC_MERGE) */
648
649 MODULE_AUTHOR("Dragos Carp");
650 MODULE_DESCRIPTION("MPC52xx PSC SPI Driver");
651 MODULE_LICENSE("GPL");
linux v2.6.22.y-op