1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright © 2009 - Maxim Levitsky
4  * driver for Ricoh xD readers
5  */
6 
7 #define DRV_NAME "r852"
8 #define pr_fmt(fmt)  DRV_NAME ": " fmt
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 */
r852_read_reg(struct r852_device * dev,int address)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 */
r852_write_reg(struct r852_device * dev,int address,uint8_t value)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 }
46 
47 
48 /* read dword sized register */
r852_read_reg_dword(struct r852_device * dev,int address)49 static inline uint32_t r852_read_reg_dword(struct r852_device *dev, int address)
50 {
51 	uint32_t reg = le32_to_cpu(readl(dev->mmio + address));
52 	return reg;
53 }
54 
55 /* write dword sized register */
r852_write_reg_dword(struct r852_device * dev,int address,uint32_t value)56 static inline void r852_write_reg_dword(struct r852_device *dev,
57 							int address, uint32_t value)
58 {
59 	writel(cpu_to_le32(value), dev->mmio + address);
60 }
61 
62 /* returns pointer to our private structure */
r852_get_dev(struct mtd_info * mtd)63 static inline struct r852_device *r852_get_dev(struct mtd_info *mtd)
64 {
65 	struct nand_chip *chip = mtd_to_nand(mtd);
66 	return nand_get_controller_data(chip);
67 }
68 
69 
70 /* check if controller supports dma */
r852_dma_test(struct r852_device * dev)71 static void r852_dma_test(struct r852_device *dev)
72 {
73 	dev->dma_usable = (r852_read_reg(dev, R852_DMA_CAP) &
74 		(R852_DMA1 | R852_DMA2)) == (R852_DMA1 | R852_DMA2);
75 
76 	if (!dev->dma_usable)
77 		message("Non dma capable device detected, dma disabled");
78 
79 	if (!r852_enable_dma) {
80 		message("disabling dma on user request");
81 		dev->dma_usable = 0;
82 	}
83 }
84 
85 /*
86  * Enable dma. Enables ether first or second stage of the DMA,
87  * Expects dev->dma_dir and dev->dma_state be set
88  */
r852_dma_enable(struct r852_device * dev)89 static void r852_dma_enable(struct r852_device *dev)
90 {
91 	uint8_t dma_reg, dma_irq_reg;
92 
93 	/* Set up dma settings */
94 	dma_reg = r852_read_reg_dword(dev, R852_DMA_SETTINGS);
95 	dma_reg &= ~(R852_DMA_READ | R852_DMA_INTERNAL | R852_DMA_MEMORY);
96 
97 	if (dev->dma_dir)
98 		dma_reg |= R852_DMA_READ;
99 
100 	if (dev->dma_state == DMA_INTERNAL) {
101 		dma_reg |= R852_DMA_INTERNAL;
102 		/* Precaution to make sure HW doesn't write */
103 			/* to random kernel memory */
104 		r852_write_reg_dword(dev, R852_DMA_ADDR,
105 			cpu_to_le32(dev->phys_bounce_buffer));
106 	} else {
107 		dma_reg |= R852_DMA_MEMORY;
108 		r852_write_reg_dword(dev, R852_DMA_ADDR,
109 			cpu_to_le32(dev->phys_dma_addr));
110 	}
111 
112 	/* Precaution: make sure write reached the device */
113 	r852_read_reg_dword(dev, R852_DMA_ADDR);
114 
115 	r852_write_reg_dword(dev, R852_DMA_SETTINGS, dma_reg);
116 
117 	/* Set dma irq */
118 	dma_irq_reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
119 	r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
120 		dma_irq_reg |
121 		R852_DMA_IRQ_INTERNAL |
122 		R852_DMA_IRQ_ERROR |
123 		R852_DMA_IRQ_MEMORY);
124 }
125 
126 /*
127  * Disable dma, called from the interrupt handler, which specifies
128  * success of the operation via 'error' argument
129  */
r852_dma_done(struct r852_device * dev,int error)130 static void r852_dma_done(struct r852_device *dev, int error)
131 {
132 	WARN_ON(dev->dma_stage == 0);
133 
134 	r852_write_reg_dword(dev, R852_DMA_IRQ_STA,
135 			r852_read_reg_dword(dev, R852_DMA_IRQ_STA));
136 
137 	r852_write_reg_dword(dev, R852_DMA_SETTINGS, 0);
138 	r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE, 0);
139 
140 	/* Precaution to make sure HW doesn't write to random kernel memory */
141 	r852_write_reg_dword(dev, R852_DMA_ADDR,
142 		cpu_to_le32(dev->phys_bounce_buffer));
143 	r852_read_reg_dword(dev, R852_DMA_ADDR);
144 
145 	dev->dma_error = error;
146 	dev->dma_stage = 0;
147 
148 	if (dev->phys_dma_addr && dev->phys_dma_addr != dev->phys_bounce_buffer)
149 		dma_unmap_single(&dev->pci_dev->dev, dev->phys_dma_addr,
150 			R852_DMA_LEN,
151 			dev->dma_dir ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
152 }
153 
154 /*
155  * Wait, till dma is done, which includes both phases of it
156  */
r852_dma_wait(struct r852_device * dev)157 static int r852_dma_wait(struct r852_device *dev)
158 {
159 	long timeout = wait_for_completion_timeout(&dev->dma_done,
160 				msecs_to_jiffies(1000));
161 	if (!timeout) {
162 		dbg("timeout waiting for DMA interrupt");
163 		return -ETIMEDOUT;
164 	}
165 
166 	return 0;
167 }
168 
169 /*
170  * Read/Write one page using dma. Only pages can be read (512 bytes)
171 */
r852_do_dma(struct r852_device * dev,uint8_t * buf,int do_read)172 static void r852_do_dma(struct r852_device *dev, uint8_t *buf, int do_read)
173 {
174 	int bounce = 0;
175 	unsigned long flags;
176 	int error;
177 
178 	dev->dma_error = 0;
179 
180 	/* Set dma direction */
181 	dev->dma_dir = do_read;
182 	dev->dma_stage = 1;
183 	reinit_completion(&dev->dma_done);
184 
185 	dbg_verbose("doing dma %s ", do_read ? "read" : "write");
186 
187 	/* Set initial dma state: for reading first fill on board buffer,
188 	  from device, for writes first fill the buffer  from memory*/
189 	dev->dma_state = do_read ? DMA_INTERNAL : DMA_MEMORY;
190 
191 	/* if incoming buffer is not page aligned, we should do bounce */
192 	if ((unsigned long)buf & (R852_DMA_LEN-1))
193 		bounce = 1;
194 
195 	if (!bounce) {
196 		dev->phys_dma_addr = dma_map_single(&dev->pci_dev->dev, buf,
197 			R852_DMA_LEN,
198 			do_read ? DMA_FROM_DEVICE : DMA_TO_DEVICE);
199 		if (dma_mapping_error(&dev->pci_dev->dev, dev->phys_dma_addr))
200 			bounce = 1;
201 	}
202 
203 	if (bounce) {
204 		dbg_verbose("dma: using bounce buffer");
205 		dev->phys_dma_addr = dev->phys_bounce_buffer;
206 		if (!do_read)
207 			memcpy(dev->bounce_buffer, buf, R852_DMA_LEN);
208 	}
209 
210 	/* Enable DMA */
211 	spin_lock_irqsave(&dev->irqlock, flags);
212 	r852_dma_enable(dev);
213 	spin_unlock_irqrestore(&dev->irqlock, flags);
214 
215 	/* Wait till complete */
216 	error = r852_dma_wait(dev);
217 
218 	if (error) {
219 		r852_dma_done(dev, error);
220 		return;
221 	}
222 
223 	if (do_read && bounce)
224 		memcpy((void *)buf, dev->bounce_buffer, R852_DMA_LEN);
225 }
226 
227 /*
228  * Program data lines of the nand chip to send data to it
229  */
r852_write_buf(struct nand_chip * chip,const uint8_t * buf,int len)230 static void r852_write_buf(struct nand_chip *chip, const uint8_t *buf, int len)
231 {
232 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
233 	uint32_t reg;
234 
235 	/* Don't allow any access to hardware if we suspect card removal */
236 	if (dev->card_unstable)
237 		return;
238 
239 	/* Special case for whole sector read */
240 	if (len == R852_DMA_LEN && dev->dma_usable) {
241 		r852_do_dma(dev, (uint8_t *)buf, 0);
242 		return;
243 	}
244 
245 	/* write DWORD chinks - faster */
246 	while (len >= 4) {
247 		reg = buf[0] | buf[1] << 8 | buf[2] << 16 | buf[3] << 24;
248 		r852_write_reg_dword(dev, R852_DATALINE, reg);
249 		buf += 4;
250 		len -= 4;
251 
252 	}
253 
254 	/* write rest */
255 	while (len > 0) {
256 		r852_write_reg(dev, R852_DATALINE, *buf++);
257 		len--;
258 	}
259 }
260 
261 /*
262  * Read data lines of the nand chip to retrieve data
263  */
r852_read_buf(struct nand_chip * chip,uint8_t * buf,int len)264 static void r852_read_buf(struct nand_chip *chip, uint8_t *buf, int len)
265 {
266 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
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  */
r852_read_byte(struct nand_chip * chip)301 static uint8_t r852_read_byte(struct nand_chip *chip)
302 {
303 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
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  */
r852_cmdctl(struct nand_chip * chip,int dat,unsigned int ctrl)315 static void r852_cmdctl(struct nand_chip *chip, int dat, unsigned int ctrl)
316 {
317 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
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 started, 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  */
r852_wait(struct nand_chip * chip)360 static int r852_wait(struct nand_chip *chip)
361 {
362 	struct r852_device *dev = nand_get_controller_data(chip);
363 
364 	unsigned long timeout;
365 	u8 status;
366 
367 	timeout = jiffies + msecs_to_jiffies(400);
368 
369 	while (time_before(jiffies, timeout))
370 		if (chip->legacy.dev_ready(chip))
371 			break;
372 
373 	nand_status_op(chip, &status);
374 
375 	/* Unfortunately, no way to send detailed error status... */
376 	if (dev->dma_error) {
377 		status |= NAND_STATUS_FAIL;
378 		dev->dma_error = 0;
379 	}
380 	return status;
381 }
382 
383 /*
384  * Check if card is ready
385  */
386 
r852_ready(struct nand_chip * chip)387 static int r852_ready(struct nand_chip *chip)
388 {
389 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
390 	if (dev->card_unstable)
391 		return 0;
392 
393 	return !(r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_BUSY);
394 }
395 
396 
397 /*
398  * Set ECC engine mode
399 */
400 
r852_ecc_hwctl(struct nand_chip * chip,int mode)401 static void r852_ecc_hwctl(struct nand_chip *chip, int mode)
402 {
403 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
404 
405 	if (dev->card_unstable)
406 		return;
407 
408 	switch (mode) {
409 	case NAND_ECC_READ:
410 	case NAND_ECC_WRITE:
411 		/* enable ecc generation/check*/
412 		dev->ctlreg |= R852_CTL_ECC_ENABLE;
413 
414 		/* flush ecc buffer */
415 		r852_write_reg(dev, R852_CTL,
416 			dev->ctlreg | R852_CTL_ECC_ACCESS);
417 
418 		r852_read_reg_dword(dev, R852_DATALINE);
419 		r852_write_reg(dev, R852_CTL, dev->ctlreg);
420 		return;
421 
422 	case NAND_ECC_READSYN:
423 		/* disable ecc generation */
424 		dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
425 		r852_write_reg(dev, R852_CTL, dev->ctlreg);
426 	}
427 }
428 
429 /*
430  * Calculate ECC, only used for writes
431  */
432 
r852_ecc_calculate(struct nand_chip * chip,const uint8_t * dat,uint8_t * ecc_code)433 static int r852_ecc_calculate(struct nand_chip *chip, const uint8_t *dat,
434 			      uint8_t *ecc_code)
435 {
436 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
437 	struct sm_oob *oob = (struct sm_oob *)ecc_code;
438 	uint32_t ecc1, ecc2;
439 
440 	if (dev->card_unstable)
441 		return 0;
442 
443 	dev->ctlreg &= ~R852_CTL_ECC_ENABLE;
444 	r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
445 
446 	ecc1 = r852_read_reg_dword(dev, R852_DATALINE);
447 	ecc2 = r852_read_reg_dword(dev, R852_DATALINE);
448 
449 	oob->ecc1[0] = (ecc1) & 0xFF;
450 	oob->ecc1[1] = (ecc1 >> 8) & 0xFF;
451 	oob->ecc1[2] = (ecc1 >> 16) & 0xFF;
452 
453 	oob->ecc2[0] = (ecc2) & 0xFF;
454 	oob->ecc2[1] = (ecc2 >> 8) & 0xFF;
455 	oob->ecc2[2] = (ecc2 >> 16) & 0xFF;
456 
457 	r852_write_reg(dev, R852_CTL, dev->ctlreg);
458 	return 0;
459 }
460 
461 /*
462  * Correct the data using ECC, hw did almost everything for us
463  */
464 
r852_ecc_correct(struct nand_chip * chip,uint8_t * dat,uint8_t * read_ecc,uint8_t * calc_ecc)465 static int r852_ecc_correct(struct nand_chip *chip, uint8_t *dat,
466 			    uint8_t *read_ecc, uint8_t *calc_ecc)
467 {
468 	uint32_t ecc_reg;
469 	uint8_t ecc_status, err_byte;
470 	int i, error = 0;
471 
472 	struct r852_device *dev = r852_get_dev(nand_to_mtd(chip));
473 
474 	if (dev->card_unstable)
475 		return 0;
476 
477 	if (dev->dma_error) {
478 		dev->dma_error = 0;
479 		return -EIO;
480 	}
481 
482 	r852_write_reg(dev, R852_CTL, dev->ctlreg | R852_CTL_ECC_ACCESS);
483 	ecc_reg = r852_read_reg_dword(dev, R852_DATALINE);
484 	r852_write_reg(dev, R852_CTL, dev->ctlreg);
485 
486 	for (i = 0 ; i <= 1 ; i++) {
487 
488 		ecc_status = (ecc_reg >> 8) & 0xFF;
489 
490 		/* ecc uncorrectable error */
491 		if (ecc_status & R852_ECC_FAIL) {
492 			dbg("ecc: unrecoverable error, in half %d", i);
493 			error = -EBADMSG;
494 			goto exit;
495 		}
496 
497 		/* correctable error */
498 		if (ecc_status & R852_ECC_CORRECTABLE) {
499 
500 			err_byte = ecc_reg & 0xFF;
501 			dbg("ecc: recoverable error, "
502 				"in half %d, byte %d, bit %d", i,
503 				err_byte, ecc_status & R852_ECC_ERR_BIT_MSK);
504 
505 			dat[err_byte] ^=
506 				1 << (ecc_status & R852_ECC_ERR_BIT_MSK);
507 			error++;
508 		}
509 
510 		dat += 256;
511 		ecc_reg >>= 16;
512 	}
513 exit:
514 	return error;
515 }
516 
517 /*
518  * This is copy of nand_read_oob_std
519  * nand_read_oob_syndrome assumes we can send column address - we can't
520  */
r852_read_oob(struct nand_chip * chip,int page)521 static int r852_read_oob(struct nand_chip *chip, int page)
522 {
523 	struct mtd_info *mtd = nand_to_mtd(chip);
524 
525 	return nand_read_oob_op(chip, page, 0, chip->oob_poi, mtd->oobsize);
526 }
527 
528 /*
529  * Start the nand engine
530  */
531 
r852_engine_enable(struct r852_device * dev)532 static 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 
r852_engine_disable(struct r852_device * dev)550 static 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 
r852_card_update_present(struct r852_device * dev)560 static 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  */
r852_update_card_detect(struct r852_device * dev)575 static 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 
media_type_show(struct device * sys_dev,struct device_attribute * attr,char * buf)589 static ssize_t 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 static DEVICE_ATTR_RO(media_type);
600 
601 
602 /* Detect properties of card in slot */
r852_update_media_status(struct r852_device * dev)603 static void r852_update_media_status(struct r852_device *dev)
604 {
605 	uint8_t reg;
606 	unsigned long flags;
607 	int readonly;
608 
609 	spin_lock_irqsave(&dev->irqlock, flags);
610 	if (!dev->card_detected) {
611 		message("card removed");
612 		spin_unlock_irqrestore(&dev->irqlock, flags);
613 		return ;
614 	}
615 
616 	readonly  = r852_read_reg(dev, R852_CARD_STA) & R852_CARD_STA_RO;
617 	reg = r852_read_reg(dev, R852_DMA_CAP);
618 	dev->sm = (reg & (R852_DMA1 | R852_DMA2)) && (reg & R852_SMBIT);
619 
620 	message("detected %s %s card in slot",
621 		dev->sm ? "SmartMedia" : "xD",
622 		readonly ? "readonly" : "writeable");
623 
624 	dev->readonly = readonly;
625 	spin_unlock_irqrestore(&dev->irqlock, flags);
626 }
627 
628 /*
629  * Register the nand device
630  * Called when the card is detected
631  */
r852_register_nand_device(struct r852_device * dev)632 static int r852_register_nand_device(struct r852_device *dev)
633 {
634 	struct mtd_info *mtd = nand_to_mtd(dev->chip);
635 
636 	WARN_ON(dev->card_registered);
637 
638 	mtd->dev.parent = &dev->pci_dev->dev;
639 
640 	if (dev->readonly)
641 		dev->chip->options |= NAND_ROM;
642 
643 	r852_engine_enable(dev);
644 
645 	if (sm_register_device(mtd, dev->sm))
646 		goto error1;
647 
648 	if (device_create_file(&mtd->dev, &dev_attr_media_type)) {
649 		message("can't create media type sysfs attribute");
650 		goto error3;
651 	}
652 
653 	dev->card_registered = 1;
654 	return 0;
655 error3:
656 	WARN_ON(mtd_device_unregister(nand_to_mtd(dev->chip)));
657 	nand_cleanup(dev->chip);
658 error1:
659 	/* Force card redetect */
660 	dev->card_detected = 0;
661 	return -1;
662 }
663 
664 /*
665  * Unregister the card
666  */
667 
r852_unregister_nand_device(struct r852_device * dev)668 static void r852_unregister_nand_device(struct r852_device *dev)
669 {
670 	struct mtd_info *mtd = nand_to_mtd(dev->chip);
671 
672 	if (!dev->card_registered)
673 		return;
674 
675 	device_remove_file(&mtd->dev, &dev_attr_media_type);
676 	WARN_ON(mtd_device_unregister(mtd));
677 	nand_cleanup(dev->chip);
678 	r852_engine_disable(dev);
679 	dev->card_registered = 0;
680 }
681 
682 /* Card state updater */
r852_card_detect_work(struct work_struct * work)683 static void r852_card_detect_work(struct work_struct *work)
684 {
685 	struct r852_device *dev =
686 		container_of(work, struct r852_device, card_detect_work.work);
687 
688 	r852_card_update_present(dev);
689 	r852_update_card_detect(dev);
690 	dev->card_unstable = 0;
691 
692 	/* False alarm */
693 	if (dev->card_detected == dev->card_registered)
694 		goto exit;
695 
696 	/* Read media properties */
697 	r852_update_media_status(dev);
698 
699 	/* Register the card */
700 	if (dev->card_detected)
701 		r852_register_nand_device(dev);
702 	else
703 		r852_unregister_nand_device(dev);
704 exit:
705 	r852_update_card_detect(dev);
706 }
707 
708 /* Ack + disable IRQ generation */
r852_disable_irqs(struct r852_device * dev)709 static void r852_disable_irqs(struct r852_device *dev)
710 {
711 	uint8_t reg;
712 	reg = r852_read_reg(dev, R852_CARD_IRQ_ENABLE);
713 	r852_write_reg(dev, R852_CARD_IRQ_ENABLE, reg & ~R852_CARD_IRQ_MASK);
714 
715 	reg = r852_read_reg_dword(dev, R852_DMA_IRQ_ENABLE);
716 	r852_write_reg_dword(dev, R852_DMA_IRQ_ENABLE,
717 					reg & ~R852_DMA_IRQ_MASK);
718 
719 	r852_write_reg(dev, R852_CARD_IRQ_STA, R852_CARD_IRQ_MASK);
720 	r852_write_reg_dword(dev, R852_DMA_IRQ_STA, R852_DMA_IRQ_MASK);
721 }
722 
723 /* Interrupt handler */
r852_irq(int irq,void * data)724 static irqreturn_t r852_irq(int irq, void *data)
725 {
726 	struct r852_device *dev = (struct r852_device *)data;
727 
728 	uint8_t card_status, dma_status;
729 	irqreturn_t ret = IRQ_NONE;
730 
731 	spin_lock(&dev->irqlock);
732 
733 	/* handle card detection interrupts first */
734 	card_status = r852_read_reg(dev, R852_CARD_IRQ_STA);
735 	r852_write_reg(dev, R852_CARD_IRQ_STA, card_status);
736 
737 	if (card_status & (R852_CARD_IRQ_INSERT|R852_CARD_IRQ_REMOVE)) {
738 
739 		ret = IRQ_HANDLED;
740 		dev->card_detected = !!(card_status & R852_CARD_IRQ_INSERT);
741 
742 		/* we shouldn't receive any interrupts if we wait for card
743 			to settle */
744 		WARN_ON(dev->card_unstable);
745 
746 		/* disable irqs while card is unstable */
747 		/* this will timeout DMA if active, but better that garbage */
748 		r852_disable_irqs(dev);
749 
750 		if (dev->card_unstable)
751 			goto out;
752 
753 		/* let, card state to settle a bit, and then do the work */
754 		dev->card_unstable = 1;
755 		queue_delayed_work(dev->card_workqueue,
756 			&dev->card_detect_work, msecs_to_jiffies(100));
757 		goto out;
758 	}
759 
760 
761 	/* Handle dma interrupts */
762 	dma_status = r852_read_reg_dword(dev, R852_DMA_IRQ_STA);
763 	r852_write_reg_dword(dev, R852_DMA_IRQ_STA, dma_status);
764 
765 	if (dma_status & R852_DMA_IRQ_MASK) {
766 
767 		ret = IRQ_HANDLED;
768 
769 		if (dma_status & R852_DMA_IRQ_ERROR) {
770 			dbg("received dma error IRQ");
771 			r852_dma_done(dev, -EIO);
772 			complete(&dev->dma_done);
773 			goto out;
774 		}
775 
776 		/* received DMA interrupt out of nowhere? */
777 		WARN_ON_ONCE(dev->dma_stage == 0);
778 
779 		if (dev->dma_stage == 0)
780 			goto out;
781 
782 		/* done device access */
783 		if (dev->dma_state == DMA_INTERNAL &&
784 				(dma_status & R852_DMA_IRQ_INTERNAL)) {
785 
786 			dev->dma_state = DMA_MEMORY;
787 			dev->dma_stage++;
788 		}
789 
790 		/* done memory DMA */
791 		if (dev->dma_state == DMA_MEMORY &&
792 				(dma_status & R852_DMA_IRQ_MEMORY)) {
793 			dev->dma_state = DMA_INTERNAL;
794 			dev->dma_stage++;
795 		}
796 
797 		/* Enable 2nd half of dma dance */
798 		if (dev->dma_stage == 2)
799 			r852_dma_enable(dev);
800 
801 		/* Operation done */
802 		if (dev->dma_stage == 3) {
803 			r852_dma_done(dev, 0);
804 			complete(&dev->dma_done);
805 		}
806 		goto out;
807 	}
808 
809 	/* Handle unknown interrupts */
810 	if (dma_status)
811 		dbg("bad dma IRQ status = %x", dma_status);
812 
813 	if (card_status & ~R852_CARD_STA_CD)
814 		dbg("strange card status = %x", card_status);
815 
816 out:
817 	spin_unlock(&dev->irqlock);
818 	return ret;
819 }
820 
r852_attach_chip(struct nand_chip * chip)821 static int r852_attach_chip(struct nand_chip *chip)
822 {
823 	if (chip->ecc.engine_type != NAND_ECC_ENGINE_TYPE_ON_HOST)
824 		return 0;
825 
826 	chip->ecc.placement = NAND_ECC_PLACEMENT_INTERLEAVED;
827 	chip->ecc.size = R852_DMA_LEN;
828 	chip->ecc.bytes = SM_OOB_SIZE;
829 	chip->ecc.strength = 2;
830 	chip->ecc.hwctl = r852_ecc_hwctl;
831 	chip->ecc.calculate = r852_ecc_calculate;
832 	chip->ecc.correct = r852_ecc_correct;
833 
834 	/* TODO: hack */
835 	chip->ecc.read_oob = r852_read_oob;
836 
837 	return 0;
838 }
839 
840 static const struct nand_controller_ops r852_ops = {
841 	.attach_chip = r852_attach_chip,
842 };
843 
r852_probe(struct pci_dev * pci_dev,const struct pci_device_id * id)844 static int  r852_probe(struct pci_dev *pci_dev, const struct pci_device_id *id)
845 {
846 	int error;
847 	struct nand_chip *chip;
848 	struct r852_device *dev;
849 
850 	/* pci initialization */
851 	error = pci_enable_device(pci_dev);
852 
853 	if (error)
854 		goto error1;
855 
856 	pci_set_master(pci_dev);
857 
858 	error = dma_set_mask(&pci_dev->dev, DMA_BIT_MASK(32));
859 	if (error)
860 		goto error2;
861 
862 	error = pci_request_regions(pci_dev, DRV_NAME);
863 
864 	if (error)
865 		goto error3;
866 
867 	error = -ENOMEM;
868 
869 	/* init nand chip, but register it only on card insert */
870 	chip = kzalloc(sizeof(struct nand_chip), GFP_KERNEL);
871 
872 	if (!chip)
873 		goto error4;
874 
875 	/* commands */
876 	chip->legacy.cmd_ctrl = r852_cmdctl;
877 	chip->legacy.waitfunc = r852_wait;
878 	chip->legacy.dev_ready = r852_ready;
879 
880 	/* I/O */
881 	chip->legacy.read_byte = r852_read_byte;
882 	chip->legacy.read_buf = r852_read_buf;
883 	chip->legacy.write_buf = r852_write_buf;
884 
885 	/* init our device structure */
886 	dev = kzalloc(sizeof(struct r852_device), GFP_KERNEL);
887 
888 	if (!dev)
889 		goto error5;
890 
891 	nand_set_controller_data(chip, dev);
892 	dev->chip = chip;
893 	dev->pci_dev = pci_dev;
894 	pci_set_drvdata(pci_dev, dev);
895 
896 	nand_controller_init(&dev->controller);
897 	dev->controller.ops = &r852_ops;
898 	chip->controller = &dev->controller;
899 
900 	dev->bounce_buffer = dma_alloc_coherent(&pci_dev->dev, R852_DMA_LEN,
901 		&dev->phys_bounce_buffer, GFP_KERNEL);
902 
903 	if (!dev->bounce_buffer)
904 		goto error6;
905 
906 
907 	error = -ENODEV;
908 	dev->mmio = pci_ioremap_bar(pci_dev, 0);
909 
910 	if (!dev->mmio)
911 		goto error7;
912 
913 	error = -ENOMEM;
914 	dev->tmp_buffer = kzalloc(SM_SECTOR_SIZE, GFP_KERNEL);
915 
916 	if (!dev->tmp_buffer)
917 		goto error8;
918 
919 	init_completion(&dev->dma_done);
920 
921 	dev->card_workqueue = create_freezable_workqueue(DRV_NAME);
922 
923 	if (!dev->card_workqueue)
924 		goto error9;
925 
926 	INIT_DELAYED_WORK(&dev->card_detect_work, r852_card_detect_work);
927 
928 	/* shutdown everything - precation */
929 	r852_engine_disable(dev);
930 	r852_disable_irqs(dev);
931 
932 	r852_dma_test(dev);
933 
934 	dev->irq = pci_dev->irq;
935 	spin_lock_init(&dev->irqlock);
936 
937 	dev->card_detected = 0;
938 	r852_card_update_present(dev);
939 
940 	/*register irq handler*/
941 	error = -ENODEV;
942 	if (request_irq(pci_dev->irq, &r852_irq, IRQF_SHARED,
943 			  DRV_NAME, dev))
944 		goto error10;
945 
946 	/* kick initial present test */
947 	queue_delayed_work(dev->card_workqueue,
948 		&dev->card_detect_work, 0);
949 
950 
951 	pr_notice("driver loaded successfully\n");
952 	return 0;
953 
954 error10:
955 	destroy_workqueue(dev->card_workqueue);
956 error9:
957 	kfree(dev->tmp_buffer);
958 error8:
959 	pci_iounmap(pci_dev, dev->mmio);
960 error7:
961 	dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
962 			  dev->phys_bounce_buffer);
963 error6:
964 	kfree(dev);
965 error5:
966 	kfree(chip);
967 error4:
968 	pci_release_regions(pci_dev);
969 error3:
970 error2:
971 	pci_disable_device(pci_dev);
972 error1:
973 	return error;
974 }
975 
r852_remove(struct pci_dev * pci_dev)976 static void r852_remove(struct pci_dev *pci_dev)
977 {
978 	struct r852_device *dev = pci_get_drvdata(pci_dev);
979 
980 	/* Stop detect workqueue -
981 		we are going to unregister the device anyway*/
982 	cancel_delayed_work_sync(&dev->card_detect_work);
983 	destroy_workqueue(dev->card_workqueue);
984 
985 	/* Unregister the device, this might make more IO */
986 	r852_unregister_nand_device(dev);
987 
988 	/* Stop interrupts */
989 	r852_disable_irqs(dev);
990 	free_irq(dev->irq, dev);
991 
992 	/* Cleanup */
993 	kfree(dev->tmp_buffer);
994 	pci_iounmap(pci_dev, dev->mmio);
995 	dma_free_coherent(&pci_dev->dev, R852_DMA_LEN, dev->bounce_buffer,
996 			  dev->phys_bounce_buffer);
997 
998 	kfree(dev->chip);
999 	kfree(dev);
1000 
1001 	/* Shutdown the PCI device */
1002 	pci_release_regions(pci_dev);
1003 	pci_disable_device(pci_dev);
1004 }
1005 
r852_shutdown(struct pci_dev * pci_dev)1006 static void r852_shutdown(struct pci_dev *pci_dev)
1007 {
1008 	struct r852_device *dev = pci_get_drvdata(pci_dev);
1009 
1010 	cancel_delayed_work_sync(&dev->card_detect_work);
1011 	r852_disable_irqs(dev);
1012 	synchronize_irq(dev->irq);
1013 	pci_disable_device(pci_dev);
1014 }
1015 
1016 #ifdef CONFIG_PM_SLEEP
r852_suspend(struct device * device)1017 static int r852_suspend(struct device *device)
1018 {
1019 	struct r852_device *dev = dev_get_drvdata(device);
1020 
1021 	if (dev->ctlreg & R852_CTL_CARDENABLE)
1022 		return -EBUSY;
1023 
1024 	/* First make sure the detect work is gone */
1025 	cancel_delayed_work_sync(&dev->card_detect_work);
1026 
1027 	/* Turn off the interrupts and stop the device */
1028 	r852_disable_irqs(dev);
1029 	r852_engine_disable(dev);
1030 
1031 	/* If card was pulled off just during the suspend, which is very
1032 		unlikely, we will remove it on resume, it too late now
1033 		anyway... */
1034 	dev->card_unstable = 0;
1035 	return 0;
1036 }
1037 
r852_resume(struct device * device)1038 static int r852_resume(struct device *device)
1039 {
1040 	struct r852_device *dev = dev_get_drvdata(device);
1041 
1042 	r852_disable_irqs(dev);
1043 	r852_card_update_present(dev);
1044 	r852_engine_disable(dev);
1045 
1046 
1047 	/* If card status changed, just do the work */
1048 	if (dev->card_detected != dev->card_registered) {
1049 		dbg("card was %s during low power state",
1050 			dev->card_detected ? "added" : "removed");
1051 
1052 		queue_delayed_work(dev->card_workqueue,
1053 		&dev->card_detect_work, msecs_to_jiffies(1000));
1054 		return 0;
1055 	}
1056 
1057 	/* Otherwise, initialize the card */
1058 	if (dev->card_registered) {
1059 		r852_engine_enable(dev);
1060 		nand_select_target(dev->chip, 0);
1061 		nand_reset_op(dev->chip);
1062 		nand_deselect_target(dev->chip);
1063 	}
1064 
1065 	/* Program card detection IRQ */
1066 	r852_update_card_detect(dev);
1067 	return 0;
1068 }
1069 #endif
1070 
1071 static const struct pci_device_id r852_pci_id_tbl[] = {
1072 
1073 	{ PCI_VDEVICE(RICOH, 0x0852), },
1074 	{ },
1075 };
1076 
1077 MODULE_DEVICE_TABLE(pci, r852_pci_id_tbl);
1078 
1079 static SIMPLE_DEV_PM_OPS(r852_pm_ops, r852_suspend, r852_resume);
1080 
1081 static struct pci_driver r852_pci_driver = {
1082 	.name		= DRV_NAME,
1083 	.id_table	= r852_pci_id_tbl,
1084 	.probe		= r852_probe,
1085 	.remove		= r852_remove,
1086 	.shutdown	= r852_shutdown,
1087 	.driver.pm	= &r852_pm_ops,
1088 };
1089 
1090 module_pci_driver(r852_pci_driver);
1091 
1092 MODULE_LICENSE("GPL");
1093 MODULE_AUTHOR("Maxim Levitsky <[email protected]>");
1094 MODULE_DESCRIPTION("Ricoh 85xx xD/smartmedia card reader driver");
1095