Linux-libre 3.11-gnu
[librecmc/linux-libre.git] / drivers / mtd / nand / r852.c
1 /*
2  * Copyright © 2009 - Maxim Levitsky
3  * driver for Ricoh xD readers
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  */
9
10 #include <linux/kernel.h>
11 #include <linux/module.h>
12 #include <linux/jiffies.h>
13 #include <linux/workqueue.h>
14 #include <linux/interrupt.h>
15 #include <linux/pci.h>
16 #include <linux/pci_ids.h>
17 #include <linux/delay.h>
18 #include <linux/slab.h>
19 #include <asm/byteorder.h>
20 #include <linux/sched.h>
21 #include "sm_common.h"
22 #include "r852.h"
23
24
25 static bool r852_enable_dma = 1;
26 module_param(r852_enable_dma, bool, S_IRUGO);
27 MODULE_PARM_DESC(r852_enable_dma, "Enable usage of the DMA (default)");
28
29 static int debug;
30 module_param(debug, int, S_IRUGO | S_IWUSR);
31 MODULE_PARM_DESC(debug, "Debug level (0-2)");
32
33 /* read register */
34 static inline uint8_t r852_read_reg(struct r852_device *dev, int address)
35 {
36         uint8_t reg = readb(dev->mmio + address);
37         return reg;
38 }
39
40 /* write register */
41 static inline void r852_write_reg(struct r852_device *dev,
42                                                 int address, uint8_t value)
43 {
44         writeb(value, dev->mmio + address);
45         mmiowb();
46 }
47
48
49 /* read dword sized register */
50 static inline uint32_t r852_read_reg_dword(struct r852_device *dev, int address)
51 {
52         uint32_t reg = le32_to_cpu(readl(dev->mmio + address));
53         return reg;
54 }
55
56 /* write dword sized register */
57 static inline void r852_write_reg_dword(struct r852_device *dev,
58                                                         int address, uint32_t value)
59 {
60         writel(cpu_to_le32(value), dev->mmio + address);
61         mmiowb();
62 }
63
64 /* returns pointer to our private structure */
65 static inline struct r852_device *r852_get_dev(struct mtd_info *mtd)
66 {
67         struct nand_chip *chip = mtd->priv;
68         return chip->priv;
69 }
70
71
72 /* check if controller supports dma */
73 static void r852_dma_test(struct r852_device *dev)
74 {
75         dev->dma_usable = (r852_read_reg(dev, R852_DMA_CAP) &
76                 (R852_DMA1 | R852_DMA2)) == (R852_DMA1 | R852_DMA2);
77
78         if (!dev->dma_usable)
79                 message("Non dma capable device detected, dma disabled");
80
81         if (!r852_enable_dma) {
82                 message("disabling dma on user request");
83                 dev->dma_usable = 0;
84         }
85 }
86
87 /*
88  * Enable dma. Enables ether first or second stage of the DMA,
89  * Expects dev->dma_dir and dev->dma_state be set
90  */
91 static void r852_dma_enable(struct r852_device *dev)
92 {
93         uint8_t dma_reg, dma_irq_reg;
94
95         /* Set up dma settings */
96         dma_reg = r852_read_reg_dword(dev, R852_DMA_SETTINGS);
97         dma_reg &= ~(R852_DMA_READ | R852_DMA_INTERNAL | R852_DMA_MEMORY);
98
99         if (dev->dma_dir)
100                 dma_reg |= R852_DMA_READ;
101
102         if (dev->dma_state == DMA_INTERNAL) {
103                 dma_reg |= R852_DMA_INTERNAL;
104                 /* Precaution to make sure HW doesn't write */
105                         /* to random kernel memory */
106                 r852_write_reg_dword(dev, R852_DMA_ADDR,
107                         cpu_to_le32(dev->phys_bounce_buffer));
108         } else {
109                 dma_reg |= R852_DMA_MEMORY;
110                 r852_write_reg_dword(dev, R852_DMA_ADDR,
111                         cpu_to_le32(dev->phys_dma_addr));
112         }
113
114         /* Precaution: make sure write reached the device */
115         r852_read_reg_dword(dev, R852_DMA_ADDR);
116
117         r852_write_reg_dword(dev, R852_DMA_SETTINGS, dma_reg);
118
119         /* Set dma irq */
120         dma_irq_reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
121         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
122                 dma_irq_reg |
123                 R852_DMA_IRQ_INTERNAL |
124                 R852_DMA_IRQ_ERROR |
125                 R852_DMA_IRQ_MEMORY);
126 }
127
128 /*
129  * Disable dma, called from the interrupt handler, which specifies
130  * success of the operation via 'error' argument
131  */
132 static void r852_dma_done(struct r852_device *dev, int error)
133 {
134         WARN_ON(dev->dma_stage == 0);
135
136         r852_write_reg_dword(dev, R852_DMA_IRQ_STA,
137                         r852_read_reg_dword(dev, R852_DMA_IRQ_STA));
138
139         r852_write_reg_dword(dev, R852_DMA_SETTINGS, 0);
140         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE, 0);
141
142         /* Precaution to make sure HW doesn't write to random kernel memory */
143         r852_write_reg_dword(dev, R852_DMA_ADDR,
144                 cpu_to_le32(dev->phys_bounce_buffer));
145         r852_read_reg_dword(dev, R852_DMA_ADDR);
146
147         dev->dma_error = error;
148         dev->dma_stage = 0;
149
150         if (dev->phys_dma_addr && dev->phys_dma_addr != dev->phys_bounce_buffer)
151                 pci_unmap_single(dev->pci_dev, dev->phys_dma_addr, R852_DMA_LEN,
152                         dev->dma_dir ? PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE);
153 }
154
155 /*
156  * Wait, till dma is done, which includes both phases of it
157  */
158 static int r852_dma_wait(struct r852_device *dev)
159 {
160         long timeout = wait_for_completion_timeout(&dev->dma_done,
161                                 msecs_to_jiffies(1000));
162         if (!timeout) {
163                 dbg("timeout waiting for DMA interrupt");
164                 return -ETIMEDOUT;
165         }
166
167         return 0;
168 }
169
170 /*
171  * Read/Write one page using dma. Only pages can be read (512 bytes)
172 */
173 static void r852_do_dma(struct r852_device *dev, uint8_t *buf, int do_read)
174 {
175         int bounce = 0;
176         unsigned long flags;
177         int error;
178
179         dev->dma_error = 0;
180
181         /* Set dma direction */
182         dev->dma_dir = do_read;
183         dev->dma_stage = 1;
184         INIT_COMPLETION(dev->dma_done);
185
186         dbg_verbose("doing dma %s ", do_read ? "read" : "write");
187
188         /* Set initial dma state: for reading first fill on board buffer,
189           from device, for writes first fill the buffer  from memory*/
190         dev->dma_state = do_read ? DMA_INTERNAL : DMA_MEMORY;
191
192         /* if incoming buffer is not page aligned, we should do bounce */
193         if ((unsigned long)buf & (R852_DMA_LEN-1))
194                 bounce = 1;
195
196         if (!bounce) {
197                 dev->phys_dma_addr = pci_map_single(dev->pci_dev, (void *)buf,
198                         R852_DMA_LEN,
199                         (do_read ? PCI_DMA_FROMDEVICE : PCI_DMA_TODEVICE));
200
201                 if (pci_dma_mapping_error(dev->pci_dev, dev->phys_dma_addr))
202                         bounce = 1;
203         }
204
205         if (bounce) {
206                 dbg_verbose("dma: using bounce buffer");
207                 dev->phys_dma_addr = dev->phys_bounce_buffer;
208                 if (!do_read)
209                         memcpy(dev->bounce_buffer, buf, R852_DMA_LEN);
210         }
211
212         /* Enable DMA */
213         spin_lock_irqsave(&dev->irqlock, flags);
214         r852_dma_enable(dev);
215         spin_unlock_irqrestore(&dev->irqlock, flags);
216
217         /* Wait till complete */
218         error = r852_dma_wait(dev);
219
220         if (error) {
221                 r852_dma_done(dev, error);
222                 return;
223         }
224
225         if (do_read && bounce)
226                 memcpy((void *)buf, dev->bounce_buffer, R852_DMA_LEN);
227 }
228
229 /*
230  * Program data lines of the nand chip to send data to it
231  */
232 void r852_write_buf(struct mtd_info *mtd, const uint8_t *buf, int len)
233 {
234         struct r852_device *dev = r852_get_dev(mtd);
235         uint32_t reg;
236
237         /* Don't allow any access to hardware if we suspect card removal */
238         if (dev->card_unstable)
239                 return;
240
241         /* Special case for whole sector read */
242         if (len == R852_DMA_LEN && dev->dma_usable) {
243                 r852_do_dma(dev, (uint8_t *)buf, 0);
244                 return;
245         }
246
247         /* write DWORD chinks - faster */
248         while (len) {
249                 reg = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24;
250                 r852_write_reg_dword(dev, R852_DATALINE, reg);
251                 buf += 4;
252                 len -= 4;
253
254         }
255
256         /* write rest */
257         while (len)
258                 r852_write_reg(dev, R852_DATALINE, *buf++);
259 }
260
261 /*
262  * Read data lines of the nand chip to retrieve data
263  */
264 void r852_read_buf(struct mtd_info *mtd, uint8_t *buf, int len)
265 {
266         struct r852_device *dev = r852_get_dev(mtd);
267         uint32_t reg;
268
269         if (dev->card_unstable) {
270                 /* since we can't signal error here, at least, return
271                         predictable buffer */
272                 memset(buf, 0, len);
273                 return;
274         }
275
276         /* special case for whole sector read */
277         if (len == R852_DMA_LEN && dev->dma_usable) {
278                 r852_do_dma(dev, buf, 1);
279                 return;
280         }
281
282         /* read in dword sized chunks */
283         while (len >= 4) {
284
285                 reg = r852_read_reg_dword(dev, R852_DATALINE);
286                 *buf++ = reg & 0xFF;
287                 *buf++ = (reg >> 8) & 0xFF;
288                 *buf++ = (reg >> 16) & 0xFF;
289                 *buf++ = (reg >> 24) & 0xFF;
290                 len -= 4;
291         }
292
293         /* read the reset by bytes */
294         while (len--)
295                 *buf++ = r852_read_reg(dev, R852_DATALINE);
296 }
297
298 /*
299  * Read one byte from nand chip
300  */
301 static uint8_t r852_read_byte(struct mtd_info *mtd)
302 {
303         struct r852_device *dev = r852_get_dev(mtd);
304
305         /* Same problem as in r852_read_buf.... */
306         if (dev->card_unstable)
307                 return 0;
308
309         return r852_read_reg(dev, R852_DATALINE);
310 }
311
312 /*
313  * Control several chip lines & send commands
314  */
315 void r852_cmdctl(struct mtd_info *mtd, int dat, unsigned int ctrl)
316 {
317         struct r852_device *dev = r852_get_dev(mtd);
318
319         if (dev->card_unstable)
320                 return;
321
322         if (ctrl & NAND_CTRL_CHANGE) {
323
324                 dev->ctlreg &= ~(R852_CTL_DATA | R852_CTL_COMMAND |
325                                  R852_CTL_ON | R852_CTL_CARDENABLE);
326
327                 if (ctrl & NAND_ALE)
328                         dev->ctlreg |= R852_CTL_DATA;
329
330                 if (ctrl & NAND_CLE)
331                         dev->ctlreg |= R852_CTL_COMMAND;
332
333                 if (ctrl & NAND_NCE)
334                         dev->ctlreg |= (R852_CTL_CARDENABLE | R852_CTL_ON);
335                 else
336                         dev->ctlreg &= ~R852_CTL_WRITE;
337
338                 /* when write is stareted, enable write access */
339                 if (dat == NAND_CMD_ERASE1)
340                         dev->ctlreg |= R852_CTL_WRITE;
341
342                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
343         }
344
345          /* HACK: NAND_CMD_SEQIN is called without NAND_CTRL_CHANGE, but we need
346                 to set write mode */
347         if (dat == NAND_CMD_SEQIN && (dev->ctlreg & R852_CTL_COMMAND)) {
348                 dev->ctlreg |= R852_CTL_WRITE;
349                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
350         }
351
352         if (dat != NAND_CMD_NONE)
353                 r852_write_reg(dev, R852_DATALINE, dat);
354 }
355
356 /*
357  * Wait till card is ready.
358  * based on nand_wait, but returns errors on DMA error
359  */
360 int r852_wait(struct mtd_info *mtd, struct nand_chip *chip)
361 {
362         struct r852_device *dev = chip->priv;
363
364         unsigned long timeout;
365         int status;
366
367         timeout = jiffies + (chip->state == FL_ERASING ?
368                 msecs_to_jiffies(400) : msecs_to_jiffies(20));
369
370         while (time_before(jiffies, timeout))
371                 if (chip->dev_ready(mtd))
372                         break;
373
374         chip->cmdfunc(mtd, NAND_CMD_STATUS, -1, -1);
375         status = (int)chip->read_byte(mtd);
376
377         /* Unfortunelly, no way to send detailed error status... */
378         if (dev->dma_error) {
379                 status |= NAND_STATUS_FAIL;
380                 dev->dma_error = 0;
381         }
382         return status;
383 }
384
385 /*
386  * Check if card is ready
387  */
388
389 int r852_ready(struct mtd_info *mtd)
390 {
391         struct r852_device *dev = r852_get_dev(mtd);
392         return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY);
393 }
394
395
396 /*
397  * Set ECC engine mode
398 */
399
400 void r852_ecc_hwctl(struct mtd_info *mtd, int mode)
401 {
402         struct r852_device *dev = r852_get_dev(mtd);
403
404         if (dev->card_unstable)
405                 return;
406
407         switch (mode) {
408         case NAND_ECC_READ:
409         case NAND_ECC_WRITE:
410                 /* enable ecc generation/check*/
411                 dev->ctlreg |= R852_CTL_ECC_ENABLE;
412
413                 /* flush ecc buffer */
414                 r852_write_reg(dev, R852_CTL,
415                         dev->ctlreg | R852_CTL_ECC_ACCESS);
416
417                 r852_read_reg_dword(dev, R852_DATALINE);
418                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
419                 return;
420
421         case NAND_ECC_READSYN:
422                 /* disable ecc generation */
423                 dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
424                 r852_write_reg(dev, R852_CTL, dev->ctlreg);
425         }
426 }
427
428 /*
429  * Calculate ECC, only used for writes
430  */
431
432 int r852_ecc_calculate(struct mtd_info *mtd, const uint8_t *dat,
433                                                         uint8_t *ecc_code)
434 {
435         struct r852_device *dev = r852_get_dev(mtd);
436         struct sm_oob *oob = (struct sm_oob *)ecc_code;
437         uint32_t ecc1, ecc2;
438
439         if (dev->card_unstable)
440                 return 0;
441
442         dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
443         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
444
445         ecc1 = r852_read_reg_dword(dev, R852_DATALINE);
446         ecc2 = r852_read_reg_dword(dev, R852_DATALINE);
447
448         oob->ecc1[0] = (ecc1) & 0xFF;
449         oob->ecc1[1] = (ecc1 >> 8) & 0xFF;
450         oob->ecc1[2] = (ecc1 >> 16) & 0xFF;
451
452         oob->ecc2[0] = (ecc2) & 0xFF;
453         oob->ecc2[1] = (ecc2 >> 8) & 0xFF;
454         oob->ecc2[2] = (ecc2 >> 16) & 0xFF;
455
456         r852_write_reg(dev, R852_CTL, dev->ctlreg);
457         return 0;
458 }
459
460 /*
461  * Correct the data using ECC, hw did almost everything for us
462  */
463
464 int r852_ecc_correct(struct mtd_info *mtd, uint8_t *dat,
465                                 uint8_t *read_ecc, uint8_t *calc_ecc)
466 {
467         uint16_t ecc_reg;
468         uint8_t ecc_status, err_byte;
469         int i, error = 0;
470
471         struct r852_device *dev = r852_get_dev(mtd);
472
473         if (dev->card_unstable)
474                 return 0;
475
476         if (dev->dma_error) {
477                 dev->dma_error = 0;
478                 return -1;
479         }
480
481         r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
482         ecc_reg = r852_read_reg_dword(dev, R852_DATALINE);
483         r852_write_reg(dev, R852_CTL, dev->ctlreg);
484
485         for (i = 0 ; i <= 1 ; i++) {
486
487                 ecc_status = (ecc_reg >> 8) & 0xFF;
488
489                 /* ecc uncorrectable error */
490                 if (ecc_status & R852_ECC_FAIL) {
491                         dbg("ecc: unrecoverable error, in half %d", i);
492                         error = -1;
493                         goto exit;
494                 }
495
496                 /* correctable error */
497                 if (ecc_status & R852_ECC_CORRECTABLE) {
498
499                         err_byte = ecc_reg & 0xFF;
500                         dbg("ecc: recoverable error, "
501                                 "in half %d, byte %d, bit %d", i,
502                                 err_byte, ecc_status & R852_ECC_ERR_BIT_MSK);
503
504                         dat[err_byte] ^=
505                                 1 << (ecc_status & R852_ECC_ERR_BIT_MSK);
506                         error++;
507                 }
508
509                 dat += 256;
510                 ecc_reg >>= 16;
511         }
512 exit:
513         return error;
514 }
515
516 /*
517  * This is copy of nand_read_oob_std
518  * nand_read_oob_syndrome assumes we can send column address - we can't
519  */
520 static int r852_read_oob(struct mtd_info *mtd, struct nand_chip *chip,
521                              int page)
522 {
523         chip->cmdfunc(mtd, NAND_CMD_READOOB, 0, page);
524         chip->read_buf(mtd, chip->oob_poi, mtd->oobsize);
525         return 0;
526 }
527
528 /*
529  * Start the nand engine
530  */
531
532 void r852_engine_enable(struct r852_device *dev)
533 {
534         if (r852_read_reg_dword(dev, R852_HW) & R852_HW_UNKNOWN) {
535                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
536                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
537         } else {
538                 r852_write_reg_dword(dev, R852_HW, R852_HW_ENABLED);
539                 r852_write_reg(dev, R852_CTL, R852_CTL_RESET | R852_CTL_ON);
540         }
541         msleep(300);
542         r852_write_reg(dev, R852_CTL, 0);
543 }
544
545
546 /*
547  * Stop the nand engine
548  */
549
550 void r852_engine_disable(struct r852_device *dev)
551 {
552         r852_write_reg_dword(dev, R852_HW, 0);
553         r852_write_reg(dev, R852_CTL, R852_CTL_RESET);
554 }
555
556 /*
557  * Test if card is present
558  */
559
560 void r852_card_update_present(struct r852_device *dev)
561 {
562         unsigned long flags;
563         uint8_t reg;
564
565         spin_lock_irqsave(&dev->irqlock, flags);
566         reg = r852_read_reg(dev, R852_CARD_STA);
567         dev->card_detected = !!(reg & R852_CARD_STA_PRESENT);
568         spin_unlock_irqrestore(&dev->irqlock, flags);
569 }
570
571 /*
572  * Update card detection IRQ state according to current card state
573  * which is read in r852_card_update_present
574  */
575 void r852_update_card_detect(struct r852_device *dev)
576 {
577         int card_detect_reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
578         dev->card_unstable = 0;
579
580         card_detect_reg &= ~(R852_CARD_IRQ_REMOVE | R852_CARD_IRQ_INSERT);
581         card_detect_reg |= R852_CARD_IRQ_GENABLE;
582
583         card_detect_reg |= dev->card_detected ?
584                 R852_CARD_IRQ_REMOVE : R852_CARD_IRQ_INSERT;
585
586         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, card_detect_reg);
587 }
588
589 ssize_t r852_media_type_show(struct device *sys_dev,
590                 struct device_attribute *attr, char *buf)
591 {
592         struct mtd_info *mtd = container_of(sys_dev, struct mtd_info, dev);
593         struct r852_device *dev = r852_get_dev(mtd);
594         char *data = dev->sm ? "smartmedia" : "xd";
595
596         strcpy(buf, data);
597         return strlen(data);
598 }
599
600 DEVICE_ATTR(media_type, S_IRUGO, r852_media_type_show, NULL);
601
602
603 /* Detect properties of card in slot */
604 void r852_update_media_status(struct r852_device *dev)
605 {
606         uint8_t reg;
607         unsigned long flags;
608         int readonly;
609
610         spin_lock_irqsave(&dev->irqlock, flags);
611         if (!dev->card_detected) {
612                 message("card removed");
613                 spin_unlock_irqrestore(&dev->irqlock, flags);
614                 return ;
615         }
616
617         readonly  = r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_RO;
618         reg = r852_read_reg(dev, R852_DMA_CAP);
619         dev->sm = (reg & (R852_DMA1 | R852_DMA2)) && (reg & R852_SMBIT);
620
621         message("detected %s %s card in slot",
622                 dev->sm ? "SmartMedia" : "xD",
623                 readonly ? "readonly" : "writeable");
624
625         dev->readonly = readonly;
626         spin_unlock_irqrestore(&dev->irqlock, flags);
627 }
628
629 /*
630  * Register the nand device
631  * Called when the card is detected
632  */
633 int r852_register_nand_device(struct r852_device *dev)
634 {
635         dev->mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL);
636
637         if (!dev->mtd)
638                 goto error1;
639
640         WARN_ON(dev->card_registred);
641
642         dev->mtd->owner = THIS_MODULE;
643         dev->mtd->priv = dev->chip;
644         dev->mtd->dev.parent = &dev->pci_dev->dev;
645
646         if (dev->readonly)
647                 dev->chip->options |= NAND_ROM;
648
649         r852_engine_enable(dev);
650
651         if (sm_register_device(dev->mtd, dev->sm))
652                 goto error2;
653
654         if (device_create_file(&dev->mtd->dev, &dev_attr_media_type))
655                 message("can't create media type sysfs attribute");
656
657         dev->card_registred = 1;
658         return 0;
659 error2:
660         kfree(dev->mtd);
661 error1:
662         /* Force card redetect */
663         dev->card_detected = 0;
664         return -1;
665 }
666
667 /*
668  * Unregister the card
669  */
670
671 void r852_unregister_nand_device(struct r852_device *dev)
672 {
673         if (!dev->card_registred)
674                 return;
675
676         device_remove_file(&dev->mtd->dev, &dev_attr_media_type);
677         nand_release(dev->mtd);
678         r852_engine_disable(dev);
679         dev->card_registred = 0;
680         kfree(dev->mtd);
681         dev->mtd = NULL;
682 }
683
684 /* Card state updater */
685 void r852_card_detect_work(struct work_struct *work)
686 {
687         struct r852_device *dev =
688                 container_of(work, struct r852_device, card_detect_work.work);
689
690         r852_card_update_present(dev);
691         r852_update_card_detect(dev);
692         dev->card_unstable = 0;
693
694         /* False alarm */
695         if (dev->card_detected == dev->card_registred)
696                 goto exit;
697
698         /* Read media properties */
699         r852_update_media_status(dev);
700
701         /* Register the card */
702         if (dev->card_detected)
703                 r852_register_nand_device(dev);
704         else
705                 r852_unregister_nand_device(dev);
706 exit:
707         r852_update_card_detect(dev);
708 }
709
710 /* Ack + disable IRQ generation */
711 static void r852_disable_irqs(struct r852_device *dev)
712 {
713         uint8_t reg;
714         reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
715         r852_write_reg(dev, R852_CARD_IRQ_ENABLE, reg & ~R852_CARD_IRQ_MASK);
716
717         reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
718         r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
719                                         reg & ~R852_DMA_IRQ_MASK);
720
721         r852_write_reg(dev, R852_CARD_IRQ_STA, R852_CARD_IRQ_MASK);
722         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, R852_DMA_IRQ_MASK);
723 }
724
725 /* Interrupt handler */
726 static irqreturn_t r852_irq(int irq, void *data)
727 {
728         struct r852_device *dev = (struct r852_device *)data;
729
730         uint8_t card_status, dma_status;
731         unsigned long flags;
732         irqreturn_t ret = IRQ_NONE;
733
734         spin_lock_irqsave(&dev->irqlock, flags);
735
736         /* handle card detection interrupts first */
737         card_status = r852_read_reg(dev, R852_CARD_IRQ_STA);
738         r852_write_reg(dev, R852_CARD_IRQ_STA, card_status);
739
740         if (card_status & (R852_CARD_IRQ_INSERT|R852_CARD_IRQ_REMOVE)) {
741
742                 ret = IRQ_HANDLED;
743                 dev->card_detected = !!(card_status & R852_CARD_IRQ_INSERT);
744
745                 /* we shouldn't receive any interrupts if we wait for card
746                         to settle */
747                 WARN_ON(dev->card_unstable);
748
749                 /* disable irqs while card is unstable */
750                 /* this will timeout DMA if active, but better that garbage */
751                 r852_disable_irqs(dev);
752
753                 if (dev->card_unstable)
754                         goto out;
755
756                 /* let, card state to settle a bit, and then do the work */
757                 dev->card_unstable = 1;
758                 queue_delayed_work(dev->card_workqueue,
759                         &dev->card_detect_work, msecs_to_jiffies(100));
760                 goto out;
761         }
762
763
764         /* Handle dma interrupts */
765         dma_status = r852_read_reg_dword(dev, R852_DMA_IRQ_STA);
766         r852_write_reg_dword(dev, R852_DMA_IRQ_STA, dma_status);
767
768         if (dma_status & R852_DMA_IRQ_MASK) {
769
770                 ret = IRQ_HANDLED;
771
772                 if (dma_status & R852_DMA_IRQ_ERROR) {
773                         dbg("received dma error IRQ");
774                         r852_dma_done(dev, -EIO);
775                         complete(&dev->dma_done);
776                         goto out;
777                 }
778
779                 /* received DMA interrupt out of nowhere? */
780                 WARN_ON_ONCE(dev->dma_stage == 0);
781
782                 if (dev->dma_stage == 0)
783                         goto out;
784
785                 /* done device access */
786                 if (dev->dma_state == DMA_INTERNAL &&
787                                 (dma_status & R852_DMA_IRQ_INTERNAL)) {
788
789                         dev->dma_state = DMA_MEMORY;
790                         dev->dma_stage++;
791                 }
792
793                 /* done memory DMA */
794                 if (dev->dma_state == DMA_MEMORY &&
795                                 (dma_status & R852_DMA_IRQ_MEMORY)) {
796                         dev->dma_state = DMA_INTERNAL;
797                         dev->dma_stage++;
798                 }
799
800                 /* Enable 2nd half of dma dance */
801                 if (dev->dma_stage == 2)
802                         r852_dma_enable(dev);
803
804                 /* Operation done */
805                 if (dev->dma_stage == 3) {
806                         r852_dma_done(dev, 0);
807                         complete(&dev->dma_done);
808                 }
809                 goto out;
810         }
811
812         /* Handle unknown interrupts */
813         if (dma_status)
814                 dbg("bad dma IRQ status = %x", dma_status);
815
816         if (card_status & ~R852_CARD_STA_CD)
817                 dbg("strange card status = %x", card_status);
818
819 out:
820         spin_unlock_irqrestore(&dev->irqlock, flags);
821         return ret;
822 }
823
824 int  r852_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
825 {
826         int error;
827         struct nand_chip *chip;
828         struct r852_device *dev;
829
830         /* pci initialization */
831         error = pci_enable_device(pci_dev);
832
833         if (error)
834                 goto error1;
835
836         pci_set_master(pci_dev);
837
838         error = pci_set_dma_mask(pci_dev, DMA_BIT_MASK(32));
839         if (error)
840                 goto error2;
841
842         error = pci_request_regions(pci_dev, DRV_NAME);
843
844         if (error)
845                 goto error3;
846
847         error = -ENOMEM;
848
849         /* init nand chip, but register it only on card insert */
850         chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
851
852         if (!chip)
853                 goto error4;
854
855         /* commands */
856         chip->cmd_ctrl = r852_cmdctl;
857         chip->waitfunc = r852_wait;
858         chip->dev_ready = r852_ready;
859
860         /* I/O */
861         chip->read_byte = r852_read_byte;
862         chip->read_buf = r852_read_buf;
863         chip->write_buf = r852_write_buf;
864
865         /* ecc */
866         chip->ecc.mode = NAND_ECC_HW_SYNDROME;
867         chip->ecc.size = R852_DMA_LEN;
868         chip->ecc.bytes = SM_OOB_SIZE;
869         chip->ecc.strength = 2;
870         chip->ecc.hwctl = r852_ecc_hwctl;
871         chip->ecc.calculate = r852_ecc_calculate;
872         chip->ecc.correct = r852_ecc_correct;
873
874         /* TODO: hack */
875         chip->ecc.read_oob = r852_read_oob;
876
877         /* init our device structure */
878         dev = kzalloc(sizeof(struct r852_device), GFP_KERNEL);
879
880         if (!dev)
881                 goto error5;
882
883         chip->priv = dev;
884         dev->chip = chip;
885         dev->pci_dev = pci_dev;
886         pci_set_drvdata(pci_dev, dev);
887
888         dev->bounce_buffer = pci_alloc_consistent(pci_dev, R852_DMA_LEN,
889                 &dev->phys_bounce_buffer);
890
891         if (!dev->bounce_buffer)
892                 goto error6;
893
894
895         error = -ENODEV;
896         dev->mmio = pci_ioremap_bar(pci_dev, 0);
897
898         if (!dev->mmio)
899                 goto error7;
900
901         error = -ENOMEM;
902         dev->tmp_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
903
904         if (!dev->tmp_buffer)
905                 goto error8;
906
907         init_completion(&dev->dma_done);
908
909         dev->card_workqueue = create_freezable_workqueue(DRV_NAME);
910
911         if (!dev->card_workqueue)
912                 goto error9;
913
914         INIT_DELAYED_WORK(&dev->card_detect_work, r852_card_detect_work);
915
916         /* shutdown everything - precation */
917         r852_engine_disable(dev);
918         r852_disable_irqs(dev);
919
920         r852_dma_test(dev);
921
922         dev->irq = pci_dev->irq;
923         spin_lock_init(&dev->irqlock);
924
925         dev->card_detected = 0;
926         r852_card_update_present(dev);
927
928         /*register irq handler*/
929         error = -ENODEV;
930         if (request_irq(pci_dev->irq, &r852_irq, IRQF_SHARED,
931                           DRV_NAME, dev))
932                 goto error10;
933
934         /* kick initial present test */
935         queue_delayed_work(dev->card_workqueue,
936                 &dev->card_detect_work, 0);
937
938
939         printk(KERN_NOTICE DRV_NAME ": driver loaded successfully\n");
940         return 0;
941
942 error10:
943         destroy_workqueue(dev->card_workqueue);
944 error9:
945         kfree(dev->tmp_buffer);
946 error8:
947         pci_iounmap(pci_dev, dev->mmio);
948 error7:
949         pci_free_consistent(pci_dev, R852_DMA_LEN,
950                 dev->bounce_buffer, dev->phys_bounce_buffer);
951 error6:
952         kfree(dev);
953 error5:
954         kfree(chip);
955 error4:
956         pci_release_regions(pci_dev);
957 error3:
958 error2:
959         pci_disable_device(pci_dev);
960 error1:
961         return error;
962 }
963
964 void r852_remove(struct pci_dev *pci_dev)
965 {
966         struct r852_device *dev = pci_get_drvdata(pci_dev);
967
968         /* Stop detect workqueue -
969                 we are going to unregister the device anyway*/
970         cancel_delayed_work_sync(&dev->card_detect_work);
971         destroy_workqueue(dev->card_workqueue);
972
973         /* Unregister the device, this might make more IO */
974         r852_unregister_nand_device(dev);
975
976         /* Stop interrupts */
977         r852_disable_irqs(dev);
978         synchronize_irq(dev->irq);
979         free_irq(dev->irq, dev);
980
981         /* Cleanup */
982         kfree(dev->tmp_buffer);
983         pci_iounmap(pci_dev, dev->mmio);
984         pci_free_consistent(pci_dev, R852_DMA_LEN,
985                 dev->bounce_buffer, dev->phys_bounce_buffer);
986
987         kfree(dev->chip);
988         kfree(dev);
989
990         /* Shutdown the PCI device */
991         pci_release_regions(pci_dev);
992         pci_disable_device(pci_dev);
993 }
994
995 void r852_shutdown(struct pci_dev *pci_dev)
996 {
997         struct r852_device *dev = pci_get_drvdata(pci_dev);
998
999         cancel_delayed_work_sync(&dev->card_detect_work);
1000         r852_disable_irqs(dev);
1001         synchronize_irq(dev->irq);
1002         pci_disable_device(pci_dev);
1003 }
1004
1005 #ifdef CONFIG_PM
1006 static int r852_suspend(struct device *device)
1007 {
1008         struct r852_device *dev = pci_get_drvdata(to_pci_dev(device));
1009
1010         if (dev->ctlreg & R852_CTL_CARDENABLE)
1011                 return -EBUSY;
1012
1013         /* First make sure the detect work is gone */
1014         cancel_delayed_work_sync(&dev->card_detect_work);
1015
1016         /* Turn off the interrupts and stop the device */
1017         r852_disable_irqs(dev);
1018         r852_engine_disable(dev);
1019
1020         /* If card was pulled off just during the suspend, which is very
1021                 unlikely, we will remove it on resume, it too late now
1022                 anyway... */
1023         dev->card_unstable = 0;
1024         return 0;
1025 }
1026
1027 static int r852_resume(struct device *device)
1028 {
1029         struct r852_device *dev = pci_get_drvdata(to_pci_dev(device));
1030
1031         r852_disable_irqs(dev);
1032         r852_card_update_present(dev);
1033         r852_engine_disable(dev);
1034
1035
1036         /* If card status changed, just do the work */
1037         if (dev->card_detected != dev->card_registred) {
1038                 dbg("card was %s during low power state",
1039                         dev->card_detected ? "added" : "removed");
1040
1041                 queue_delayed_work(dev->card_workqueue,
1042                 &dev->card_detect_work, msecs_to_jiffies(1000));
1043                 return 0;
1044         }
1045
1046         /* Otherwise, initialize the card */
1047         if (dev->card_registred) {
1048                 r852_engine_enable(dev);
1049                 dev->chip->select_chip(dev->mtd, 0);
1050                 dev->chip->cmdfunc(dev->mtd, NAND_CMD_RESET, -1, -1);
1051                 dev->chip->select_chip(dev->mtd, -1);
1052         }
1053
1054         /* Program card detection IRQ */
1055         r852_update_card_detect(dev);
1056         return 0;
1057 }
1058 #else
1059 #define r852_suspend    NULL
1060 #define r852_resume     NULL
1061 #endif
1062
1063 static const struct pci_device_id r852_pci_id_tbl[] = {
1064
1065         { PCI_VDEVICE(RICOH, 0x0852), },
1066         { },
1067 };
1068
1069 MODULE_DEVICE_TABLE(pci, r852_pci_id_tbl);
1070
1071 static SIMPLE_DEV_PM_OPS(r852_pm_ops, r852_suspend, r852_resume);
1072
1073 static struct pci_driver r852_pci_driver = {
1074         .name           = DRV_NAME,
1075         .id_table       = r852_pci_id_tbl,
1076         .probe          = r852_probe,
1077         .remove         = r852_remove,
1078         .shutdown       = r852_shutdown,
1079         .driver.pm      = &r852_pm_ops,
1080 };
1081
1082 module_pci_driver(r852_pci_driver);
1083
1084 MODULE_LICENSE("GPL");
1085 MODULE_AUTHOR("Maxim Levitsky <maximlevitsky@gmail.com>");
1086 MODULE_DESCRIPTION("Ricoh 85xx xD/smartmedia card reader driver");