xref: /openbmc/linux/drivers/net/can/sja1000/peak_pci.c (revision 835fd614)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2007, 2011 Wolfgang Grandegger <wg@grandegger.com>
4  * Copyright (C) 2012 Stephane Grosjean <s.grosjean@peak-system.com>
5  *
6  * Derived from the PCAN project file driver/src/pcan_pci.c:
7  *
8  * Copyright (C) 2001-2006  PEAK System-Technik GmbH
9  */
10 
11 #include <linux/kernel.h>
12 #include <linux/module.h>
13 #include <linux/interrupt.h>
14 #include <linux/netdevice.h>
15 #include <linux/delay.h>
16 #include <linux/pci.h>
17 #include <linux/io.h>
18 #include <linux/i2c.h>
19 #include <linux/i2c-algo-bit.h>
20 #include <linux/can.h>
21 #include <linux/can/dev.h>
22 
23 #include "sja1000.h"
24 
25 MODULE_AUTHOR("Stephane Grosjean <s.grosjean@peak-system.com>");
26 MODULE_DESCRIPTION("Socket-CAN driver for PEAK PCAN PCI family cards");
27 MODULE_SUPPORTED_DEVICE("PEAK PCAN PCI/PCIe/PCIeC miniPCI CAN cards");
28 MODULE_SUPPORTED_DEVICE("PEAK PCAN miniPCIe/cPCI PC/104+ PCI/104e CAN Cards");
29 MODULE_LICENSE("GPL v2");
30 
31 #define DRV_NAME  "peak_pci"
32 
33 struct peak_pciec_card;
34 struct peak_pci_chan {
35 	void __iomem *cfg_base;		/* Common for all channels */
36 	struct net_device *prev_dev;	/* Chain of network devices */
37 	u16 icr_mask;			/* Interrupt mask for fast ack */
38 	struct peak_pciec_card *pciec_card;	/* only for PCIeC LEDs */
39 };
40 
41 #define PEAK_PCI_CAN_CLOCK	(16000000 / 2)
42 
43 #define PEAK_PCI_CDR		(CDR_CBP | CDR_CLKOUT_MASK)
44 #define PEAK_PCI_OCR		OCR_TX0_PUSHPULL
45 
46 /*
47  * Important PITA registers
48  */
49 #define PITA_ICR		0x00	/* Interrupt control register */
50 #define PITA_GPIOICR		0x18	/* GPIO interface control register */
51 #define PITA_MISC		0x1C	/* Miscellaneous register */
52 
53 #define PEAK_PCI_CFG_SIZE	0x1000	/* Size of the config PCI bar */
54 #define PEAK_PCI_CHAN_SIZE	0x0400	/* Size used by the channel */
55 
56 #define PEAK_PCI_VENDOR_ID	0x001C	/* The PCI device and vendor IDs */
57 #define PEAK_PCI_DEVICE_ID	0x0001	/* for PCI/PCIe slot cards */
58 #define PEAK_PCIEC_DEVICE_ID	0x0002	/* for ExpressCard slot cards */
59 #define PEAK_PCIE_DEVICE_ID	0x0003	/* for nextgen PCIe slot cards */
60 #define PEAK_CPCI_DEVICE_ID	0x0004	/* for nextgen cPCI slot cards */
61 #define PEAK_MPCI_DEVICE_ID	0x0005	/* for nextgen miniPCI slot cards */
62 #define PEAK_PC_104P_DEVICE_ID	0x0006	/* PCAN-PC/104+ cards */
63 #define PEAK_PCI_104E_DEVICE_ID	0x0007	/* PCAN-PCI/104 Express cards */
64 #define PEAK_MPCIE_DEVICE_ID	0x0008	/* The miniPCIe slot cards */
65 #define PEAK_PCIE_OEM_ID	0x0009	/* PCAN-PCI Express OEM */
66 #define PEAK_PCIEC34_DEVICE_ID	0x000A	/* PCAN-PCI Express 34 (one channel) */
67 
68 #define PEAK_PCI_CHAN_MAX	4
69 
70 static const u16 peak_pci_icr_masks[PEAK_PCI_CHAN_MAX] = {
71 	0x02, 0x01, 0x40, 0x80
72 };
73 
74 static const struct pci_device_id peak_pci_tbl[] = {
75 	{PEAK_PCI_VENDOR_ID, PEAK_PCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
76 	{PEAK_PCI_VENDOR_ID, PEAK_PCIE_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
77 	{PEAK_PCI_VENDOR_ID, PEAK_MPCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
78 	{PEAK_PCI_VENDOR_ID, PEAK_MPCIE_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
79 	{PEAK_PCI_VENDOR_ID, PEAK_PC_104P_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
80 	{PEAK_PCI_VENDOR_ID, PEAK_PCI_104E_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
81 	{PEAK_PCI_VENDOR_ID, PEAK_CPCI_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
82 	{PEAK_PCI_VENDOR_ID, PEAK_PCIE_OEM_ID, PCI_ANY_ID, PCI_ANY_ID,},
83 #ifdef CONFIG_CAN_PEAK_PCIEC
84 	{PEAK_PCI_VENDOR_ID, PEAK_PCIEC_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
85 	{PEAK_PCI_VENDOR_ID, PEAK_PCIEC34_DEVICE_ID, PCI_ANY_ID, PCI_ANY_ID,},
86 #endif
87 	{0,}
88 };
89 
90 MODULE_DEVICE_TABLE(pci, peak_pci_tbl);
91 
92 #ifdef CONFIG_CAN_PEAK_PCIEC
93 /*
94  * PCAN-ExpressCard needs I2C bit-banging configuration option.
95  */
96 
97 /* GPIOICR byte access offsets */
98 #define PITA_GPOUT		0x18	/* GPx output value */
99 #define PITA_GPIN		0x19	/* GPx input value */
100 #define PITA_GPOEN		0x1A	/* configure GPx as output pin */
101 
102 /* I2C GP bits */
103 #define PITA_GPIN_SCL		0x01	/* Serial Clock Line */
104 #define PITA_GPIN_SDA		0x04	/* Serial DAta line */
105 
106 #define PCA9553_1_SLAVEADDR	(0xC4 >> 1)
107 
108 /* PCA9553 LS0 fields values */
109 enum {
110 	PCA9553_LOW,
111 	PCA9553_HIGHZ,
112 	PCA9553_PWM0,
113 	PCA9553_PWM1
114 };
115 
116 /* LEDs control */
117 #define PCA9553_ON		PCA9553_LOW
118 #define PCA9553_OFF		PCA9553_HIGHZ
119 #define PCA9553_SLOW		PCA9553_PWM0
120 #define PCA9553_FAST		PCA9553_PWM1
121 
122 #define PCA9553_LED(c)		(1 << (c))
123 #define PCA9553_LED_STATE(s, c)	((s) << ((c) << 1))
124 
125 #define PCA9553_LED_ON(c)	PCA9553_LED_STATE(PCA9553_ON, c)
126 #define PCA9553_LED_OFF(c)	PCA9553_LED_STATE(PCA9553_OFF, c)
127 #define PCA9553_LED_SLOW(c)	PCA9553_LED_STATE(PCA9553_SLOW, c)
128 #define PCA9553_LED_FAST(c)	PCA9553_LED_STATE(PCA9553_FAST, c)
129 #define PCA9553_LED_MASK(c)	PCA9553_LED_STATE(0x03, c)
130 
131 #define PCA9553_LED_OFF_ALL	(PCA9553_LED_OFF(0) | PCA9553_LED_OFF(1))
132 
133 #define PCA9553_LS0_INIT	0x40 /* initial value (!= from 0x00) */
134 
135 struct peak_pciec_chan {
136 	struct net_device *netdev;
137 	unsigned long prev_rx_bytes;
138 	unsigned long prev_tx_bytes;
139 };
140 
141 struct peak_pciec_card {
142 	void __iomem *cfg_base;		/* Common for all channels */
143 	void __iomem *reg_base;		/* first channel base address */
144 	u8 led_cache;			/* leds state cache */
145 
146 	/* PCIExpressCard i2c data */
147 	struct i2c_algo_bit_data i2c_bit;
148 	struct i2c_adapter led_chip;
149 	struct delayed_work led_work;	/* led delayed work */
150 	int chan_count;
151 	struct peak_pciec_chan channel[PEAK_PCI_CHAN_MAX];
152 };
153 
154 /* "normal" pci register write callback is overloaded for leds control */
155 static void peak_pci_write_reg(const struct sja1000_priv *priv,
156 			       int port, u8 val);
157 
158 static inline void pita_set_scl_highz(struct peak_pciec_card *card)
159 {
160 	u8 gp_outen = readb(card->cfg_base + PITA_GPOEN) & ~PITA_GPIN_SCL;
161 	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
162 }
163 
164 static inline void pita_set_sda_highz(struct peak_pciec_card *card)
165 {
166 	u8 gp_outen = readb(card->cfg_base + PITA_GPOEN) & ~PITA_GPIN_SDA;
167 	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
168 }
169 
170 static void peak_pciec_init_pita_gpio(struct peak_pciec_card *card)
171 {
172 	/* raise SCL & SDA GPIOs to high-Z */
173 	pita_set_scl_highz(card);
174 	pita_set_sda_highz(card);
175 }
176 
177 static void pita_setsda(void *data, int state)
178 {
179 	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
180 	u8 gp_out, gp_outen;
181 
182 	/* set output sda always to 0 */
183 	gp_out = readb(card->cfg_base + PITA_GPOUT) & ~PITA_GPIN_SDA;
184 	writeb(gp_out, card->cfg_base + PITA_GPOUT);
185 
186 	/* control output sda with GPOEN */
187 	gp_outen = readb(card->cfg_base + PITA_GPOEN);
188 	if (state)
189 		gp_outen &= ~PITA_GPIN_SDA;
190 	else
191 		gp_outen |= PITA_GPIN_SDA;
192 
193 	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
194 }
195 
196 static void pita_setscl(void *data, int state)
197 {
198 	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
199 	u8 gp_out, gp_outen;
200 
201 	/* set output scl always to 0 */
202 	gp_out = readb(card->cfg_base + PITA_GPOUT) & ~PITA_GPIN_SCL;
203 	writeb(gp_out, card->cfg_base + PITA_GPOUT);
204 
205 	/* control output scl with GPOEN */
206 	gp_outen = readb(card->cfg_base + PITA_GPOEN);
207 	if (state)
208 		gp_outen &= ~PITA_GPIN_SCL;
209 	else
210 		gp_outen |= PITA_GPIN_SCL;
211 
212 	writeb(gp_outen, card->cfg_base + PITA_GPOEN);
213 }
214 
215 static int pita_getsda(void *data)
216 {
217 	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
218 
219 	/* set tristate */
220 	pita_set_sda_highz(card);
221 
222 	return (readb(card->cfg_base + PITA_GPIN) & PITA_GPIN_SDA) ? 1 : 0;
223 }
224 
225 static int pita_getscl(void *data)
226 {
227 	struct peak_pciec_card *card = (struct peak_pciec_card *)data;
228 
229 	/* set tristate */
230 	pita_set_scl_highz(card);
231 
232 	return (readb(card->cfg_base + PITA_GPIN) & PITA_GPIN_SCL) ? 1 : 0;
233 }
234 
235 /*
236  * write commands to the LED chip though the I2C-bus of the PCAN-PCIeC
237  */
238 static int peak_pciec_write_pca9553(struct peak_pciec_card *card,
239 				    u8 offset, u8 data)
240 {
241 	u8 buffer[2] = {
242 		offset,
243 		data
244 	};
245 	struct i2c_msg msg = {
246 		.addr = PCA9553_1_SLAVEADDR,
247 		.len = 2,
248 		.buf = buffer,
249 	};
250 	int ret;
251 
252 	/* cache led mask */
253 	if ((offset == 5) && (data == card->led_cache))
254 		return 0;
255 
256 	ret = i2c_transfer(&card->led_chip, &msg, 1);
257 	if (ret < 0)
258 		return ret;
259 
260 	if (offset == 5)
261 		card->led_cache = data;
262 
263 	return 0;
264 }
265 
266 /*
267  * delayed work callback used to control the LEDs
268  */
269 static void peak_pciec_led_work(struct work_struct *work)
270 {
271 	struct peak_pciec_card *card =
272 		container_of(work, struct peak_pciec_card, led_work.work);
273 	struct net_device *netdev;
274 	u8 new_led = card->led_cache;
275 	int i, up_count = 0;
276 
277 	/* first check what is to do */
278 	for (i = 0; i < card->chan_count; i++) {
279 		/* default is: not configured */
280 		new_led &= ~PCA9553_LED_MASK(i);
281 		new_led |= PCA9553_LED_ON(i);
282 
283 		netdev = card->channel[i].netdev;
284 		if (!netdev || !(netdev->flags & IFF_UP))
285 			continue;
286 
287 		up_count++;
288 
289 		/* no activity (but configured) */
290 		new_led &= ~PCA9553_LED_MASK(i);
291 		new_led |= PCA9553_LED_SLOW(i);
292 
293 		/* if bytes counters changed, set fast blinking led */
294 		if (netdev->stats.rx_bytes != card->channel[i].prev_rx_bytes) {
295 			card->channel[i].prev_rx_bytes = netdev->stats.rx_bytes;
296 			new_led &= ~PCA9553_LED_MASK(i);
297 			new_led |= PCA9553_LED_FAST(i);
298 		}
299 		if (netdev->stats.tx_bytes != card->channel[i].prev_tx_bytes) {
300 			card->channel[i].prev_tx_bytes = netdev->stats.tx_bytes;
301 			new_led &= ~PCA9553_LED_MASK(i);
302 			new_led |= PCA9553_LED_FAST(i);
303 		}
304 	}
305 
306 	/* check if LS0 settings changed, only update i2c if so */
307 	peak_pciec_write_pca9553(card, 5, new_led);
308 
309 	/* restart timer (except if no more configured channels) */
310 	if (up_count)
311 		schedule_delayed_work(&card->led_work, HZ);
312 }
313 
314 /*
315  * set LEDs blinking state
316  */
317 static void peak_pciec_set_leds(struct peak_pciec_card *card, u8 led_mask, u8 s)
318 {
319 	u8 new_led = card->led_cache;
320 	int i;
321 
322 	/* first check what is to do */
323 	for (i = 0; i < card->chan_count; i++)
324 		if (led_mask & PCA9553_LED(i)) {
325 			new_led &= ~PCA9553_LED_MASK(i);
326 			new_led |= PCA9553_LED_STATE(s, i);
327 		}
328 
329 	/* check if LS0 settings changed, only update i2c if so */
330 	peak_pciec_write_pca9553(card, 5, new_led);
331 }
332 
333 /*
334  * start one second delayed work to control LEDs
335  */
336 static void peak_pciec_start_led_work(struct peak_pciec_card *card)
337 {
338 	schedule_delayed_work(&card->led_work, HZ);
339 }
340 
341 /*
342  * stop LEDs delayed work
343  */
344 static void peak_pciec_stop_led_work(struct peak_pciec_card *card)
345 {
346 	cancel_delayed_work_sync(&card->led_work);
347 }
348 
349 /*
350  * initialize the PCA9553 4-bit I2C-bus LED chip
351  */
352 static int peak_pciec_init_leds(struct peak_pciec_card *card)
353 {
354 	int err;
355 
356 	/* prescaler for frequency 0: "SLOW" = 1 Hz = "44" */
357 	err = peak_pciec_write_pca9553(card, 1, 44 / 1);
358 	if (err)
359 		return err;
360 
361 	/* duty cycle 0: 50% */
362 	err = peak_pciec_write_pca9553(card, 2, 0x80);
363 	if (err)
364 		return err;
365 
366 	/* prescaler for frequency 1: "FAST" = 5 Hz */
367 	err = peak_pciec_write_pca9553(card, 3, 44 / 5);
368 	if (err)
369 		return err;
370 
371 	/* duty cycle 1: 50% */
372 	err = peak_pciec_write_pca9553(card, 4, 0x80);
373 	if (err)
374 		return err;
375 
376 	/* switch LEDs to initial state */
377 	return peak_pciec_write_pca9553(card, 5, PCA9553_LS0_INIT);
378 }
379 
380 /*
381  * restore LEDs state to off peak_pciec_leds_exit
382  */
383 static void peak_pciec_leds_exit(struct peak_pciec_card *card)
384 {
385 	/* switch LEDs to off */
386 	peak_pciec_write_pca9553(card, 5, PCA9553_LED_OFF_ALL);
387 }
388 
389 /*
390  * normal write sja1000 register method overloaded to catch when controller
391  * is started or stopped, to control leds
392  */
393 static void peak_pciec_write_reg(const struct sja1000_priv *priv,
394 				 int port, u8 val)
395 {
396 	struct peak_pci_chan *chan = priv->priv;
397 	struct peak_pciec_card *card = chan->pciec_card;
398 	int c = (priv->reg_base - card->reg_base) / PEAK_PCI_CHAN_SIZE;
399 
400 	/* sja1000 register changes control the leds state */
401 	if (port == SJA1000_MOD)
402 		switch (val) {
403 		case MOD_RM:
404 			/* Reset Mode: set led on */
405 			peak_pciec_set_leds(card, PCA9553_LED(c), PCA9553_ON);
406 			break;
407 		case 0x00:
408 			/* Normal Mode: led slow blinking and start led timer */
409 			peak_pciec_set_leds(card, PCA9553_LED(c), PCA9553_SLOW);
410 			peak_pciec_start_led_work(card);
411 			break;
412 		default:
413 			break;
414 		}
415 
416 	/* call base function */
417 	peak_pci_write_reg(priv, port, val);
418 }
419 
420 static const struct i2c_algo_bit_data peak_pciec_i2c_bit_ops = {
421 	.setsda	= pita_setsda,
422 	.setscl	= pita_setscl,
423 	.getsda	= pita_getsda,
424 	.getscl	= pita_getscl,
425 	.udelay	= 10,
426 	.timeout = HZ,
427 };
428 
429 static int peak_pciec_probe(struct pci_dev *pdev, struct net_device *dev)
430 {
431 	struct sja1000_priv *priv = netdev_priv(dev);
432 	struct peak_pci_chan *chan = priv->priv;
433 	struct peak_pciec_card *card;
434 	int err;
435 
436 	/* copy i2c object address from 1st channel */
437 	if (chan->prev_dev) {
438 		struct sja1000_priv *prev_priv = netdev_priv(chan->prev_dev);
439 		struct peak_pci_chan *prev_chan = prev_priv->priv;
440 
441 		card = prev_chan->pciec_card;
442 		if (!card)
443 			return -ENODEV;
444 
445 	/* channel is the first one: do the init part */
446 	} else {
447 		/* create the bit banging I2C adapter structure */
448 		card = kzalloc(sizeof(struct peak_pciec_card), GFP_KERNEL);
449 		if (!card)
450 			return -ENOMEM;
451 
452 		card->cfg_base = chan->cfg_base;
453 		card->reg_base = priv->reg_base;
454 
455 		card->led_chip.owner = THIS_MODULE;
456 		card->led_chip.dev.parent = &pdev->dev;
457 		card->led_chip.algo_data = &card->i2c_bit;
458 		strncpy(card->led_chip.name, "peak_i2c",
459 			sizeof(card->led_chip.name));
460 
461 		card->i2c_bit = peak_pciec_i2c_bit_ops;
462 		card->i2c_bit.udelay = 10;
463 		card->i2c_bit.timeout = HZ;
464 		card->i2c_bit.data = card;
465 
466 		peak_pciec_init_pita_gpio(card);
467 
468 		err = i2c_bit_add_bus(&card->led_chip);
469 		if (err) {
470 			dev_err(&pdev->dev, "i2c init failed\n");
471 			goto pciec_init_err_1;
472 		}
473 
474 		err = peak_pciec_init_leds(card);
475 		if (err) {
476 			dev_err(&pdev->dev, "leds hardware init failed\n");
477 			goto pciec_init_err_2;
478 		}
479 
480 		INIT_DELAYED_WORK(&card->led_work, peak_pciec_led_work);
481 		/* PCAN-ExpressCard needs its own callback for leds */
482 		priv->write_reg = peak_pciec_write_reg;
483 	}
484 
485 	chan->pciec_card = card;
486 	card->channel[card->chan_count++].netdev = dev;
487 
488 	return 0;
489 
490 pciec_init_err_2:
491 	i2c_del_adapter(&card->led_chip);
492 
493 pciec_init_err_1:
494 	peak_pciec_init_pita_gpio(card);
495 	kfree(card);
496 
497 	return err;
498 }
499 
500 static void peak_pciec_remove(struct peak_pciec_card *card)
501 {
502 	peak_pciec_stop_led_work(card);
503 	peak_pciec_leds_exit(card);
504 	i2c_del_adapter(&card->led_chip);
505 	peak_pciec_init_pita_gpio(card);
506 	kfree(card);
507 }
508 
509 #else /* CONFIG_CAN_PEAK_PCIEC */
510 
511 /*
512  * Placebo functions when PCAN-ExpressCard support is not selected
513  */
514 static inline int peak_pciec_probe(struct pci_dev *pdev, struct net_device *dev)
515 {
516 	return -ENODEV;
517 }
518 
519 static inline void peak_pciec_remove(struct peak_pciec_card *card)
520 {
521 }
522 #endif /* CONFIG_CAN_PEAK_PCIEC */
523 
524 static u8 peak_pci_read_reg(const struct sja1000_priv *priv, int port)
525 {
526 	return readb(priv->reg_base + (port << 2));
527 }
528 
529 static void peak_pci_write_reg(const struct sja1000_priv *priv,
530 			       int port, u8 val)
531 {
532 	writeb(val, priv->reg_base + (port << 2));
533 }
534 
535 static void peak_pci_post_irq(const struct sja1000_priv *priv)
536 {
537 	struct peak_pci_chan *chan = priv->priv;
538 	u16 icr;
539 
540 	/* Select and clear in PITA stored interrupt */
541 	icr = readw(chan->cfg_base + PITA_ICR);
542 	if (icr & chan->icr_mask)
543 		writew(chan->icr_mask, chan->cfg_base + PITA_ICR);
544 }
545 
546 static int peak_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
547 {
548 	struct sja1000_priv *priv;
549 	struct peak_pci_chan *chan;
550 	struct net_device *dev, *prev_dev;
551 	void __iomem *cfg_base, *reg_base;
552 	u16 sub_sys_id, icr;
553 	int i, err, channels;
554 
555 	err = pci_enable_device(pdev);
556 	if (err)
557 		return err;
558 
559 	err = pci_request_regions(pdev, DRV_NAME);
560 	if (err)
561 		goto failure_disable_pci;
562 
563 	err = pci_read_config_word(pdev, 0x2e, &sub_sys_id);
564 	if (err)
565 		goto failure_release_regions;
566 
567 	dev_dbg(&pdev->dev, "probing device %04x:%04x:%04x\n",
568 		pdev->vendor, pdev->device, sub_sys_id);
569 
570 	err = pci_write_config_word(pdev, 0x44, 0);
571 	if (err)
572 		goto failure_release_regions;
573 
574 	if (sub_sys_id >= 12)
575 		channels = 4;
576 	else if (sub_sys_id >= 10)
577 		channels = 3;
578 	else if (sub_sys_id >= 4)
579 		channels = 2;
580 	else
581 		channels = 1;
582 
583 	cfg_base = pci_iomap(pdev, 0, PEAK_PCI_CFG_SIZE);
584 	if (!cfg_base) {
585 		dev_err(&pdev->dev, "failed to map PCI resource #0\n");
586 		err = -ENOMEM;
587 		goto failure_release_regions;
588 	}
589 
590 	reg_base = pci_iomap(pdev, 1, PEAK_PCI_CHAN_SIZE * channels);
591 	if (!reg_base) {
592 		dev_err(&pdev->dev, "failed to map PCI resource #1\n");
593 		err = -ENOMEM;
594 		goto failure_unmap_cfg_base;
595 	}
596 
597 	/* Set GPIO control register */
598 	writew(0x0005, cfg_base + PITA_GPIOICR + 2);
599 	/* Enable all channels of this card */
600 	writeb(0x00, cfg_base + PITA_GPIOICR);
601 	/* Toggle reset */
602 	writeb(0x05, cfg_base + PITA_MISC + 3);
603 	usleep_range(5000, 6000);
604 	/* Leave parport mux mode */
605 	writeb(0x04, cfg_base + PITA_MISC + 3);
606 
607 	icr = readw(cfg_base + PITA_ICR + 2);
608 
609 	for (i = 0; i < channels; i++) {
610 		dev = alloc_sja1000dev(sizeof(struct peak_pci_chan));
611 		if (!dev) {
612 			err = -ENOMEM;
613 			goto failure_remove_channels;
614 		}
615 
616 		priv = netdev_priv(dev);
617 		chan = priv->priv;
618 
619 		chan->cfg_base = cfg_base;
620 		priv->reg_base = reg_base + i * PEAK_PCI_CHAN_SIZE;
621 
622 		priv->read_reg = peak_pci_read_reg;
623 		priv->write_reg = peak_pci_write_reg;
624 		priv->post_irq = peak_pci_post_irq;
625 
626 		priv->can.clock.freq = PEAK_PCI_CAN_CLOCK;
627 		priv->ocr = PEAK_PCI_OCR;
628 		priv->cdr = PEAK_PCI_CDR;
629 		/* Neither a slave nor a single device distributes the clock */
630 		if (channels == 1 || i > 0)
631 			priv->cdr |= CDR_CLK_OFF;
632 
633 		/* Setup interrupt handling */
634 		priv->irq_flags = IRQF_SHARED;
635 		dev->irq = pdev->irq;
636 
637 		chan->icr_mask = peak_pci_icr_masks[i];
638 		icr |= chan->icr_mask;
639 
640 		SET_NETDEV_DEV(dev, &pdev->dev);
641 		dev->dev_id = i;
642 
643 		/* Create chain of SJA1000 devices */
644 		chan->prev_dev = pci_get_drvdata(pdev);
645 		pci_set_drvdata(pdev, dev);
646 
647 		/*
648 		 * PCAN-ExpressCard needs some additional i2c init.
649 		 * This must be done *before* register_sja1000dev() but
650 		 * *after* devices linkage
651 		 */
652 		if (pdev->device == PEAK_PCIEC_DEVICE_ID ||
653 		    pdev->device == PEAK_PCIEC34_DEVICE_ID) {
654 			err = peak_pciec_probe(pdev, dev);
655 			if (err) {
656 				dev_err(&pdev->dev,
657 					"failed to probe device (err %d)\n",
658 					err);
659 				goto failure_free_dev;
660 			}
661 		}
662 
663 		err = register_sja1000dev(dev);
664 		if (err) {
665 			dev_err(&pdev->dev, "failed to register device\n");
666 			goto failure_free_dev;
667 		}
668 
669 		dev_info(&pdev->dev,
670 			 "%s at reg_base=0x%p cfg_base=0x%p irq=%d\n",
671 			 dev->name, priv->reg_base, chan->cfg_base, dev->irq);
672 	}
673 
674 	/* Enable interrupts */
675 	writew(icr, cfg_base + PITA_ICR + 2);
676 
677 	return 0;
678 
679 failure_free_dev:
680 	pci_set_drvdata(pdev, chan->prev_dev);
681 	free_sja1000dev(dev);
682 
683 failure_remove_channels:
684 	/* Disable interrupts */
685 	writew(0x0, cfg_base + PITA_ICR + 2);
686 
687 	chan = NULL;
688 	for (dev = pci_get_drvdata(pdev); dev; dev = prev_dev) {
689 		priv = netdev_priv(dev);
690 		chan = priv->priv;
691 		prev_dev = chan->prev_dev;
692 
693 		unregister_sja1000dev(dev);
694 		free_sja1000dev(dev);
695 	}
696 
697 	/* free any PCIeC resources too */
698 	if (chan && chan->pciec_card)
699 		peak_pciec_remove(chan->pciec_card);
700 
701 	pci_iounmap(pdev, reg_base);
702 
703 failure_unmap_cfg_base:
704 	pci_iounmap(pdev, cfg_base);
705 
706 failure_release_regions:
707 	pci_release_regions(pdev);
708 
709 failure_disable_pci:
710 	pci_disable_device(pdev);
711 
712 	/* pci_xxx_config_word() return positive PCIBIOS_xxx error codes while
713 	 * the probe() function must return a negative errno in case of failure
714 	 * (err is unchanged if negative) */
715 	return pcibios_err_to_errno(err);
716 }
717 
718 static void peak_pci_remove(struct pci_dev *pdev)
719 {
720 	struct net_device *dev = pci_get_drvdata(pdev); /* Last device */
721 	struct sja1000_priv *priv = netdev_priv(dev);
722 	struct peak_pci_chan *chan = priv->priv;
723 	void __iomem *cfg_base = chan->cfg_base;
724 	void __iomem *reg_base = priv->reg_base;
725 
726 	/* Disable interrupts */
727 	writew(0x0, cfg_base + PITA_ICR + 2);
728 
729 	/* Loop over all registered devices */
730 	while (1) {
731 		struct net_device *prev_dev = chan->prev_dev;
732 
733 		dev_info(&pdev->dev, "removing device %s\n", dev->name);
734 		unregister_sja1000dev(dev);
735 		free_sja1000dev(dev);
736 		dev = prev_dev;
737 
738 		if (!dev) {
739 			/* do that only for first channel */
740 			if (chan->pciec_card)
741 				peak_pciec_remove(chan->pciec_card);
742 			break;
743 		}
744 		priv = netdev_priv(dev);
745 		chan = priv->priv;
746 	}
747 
748 	pci_iounmap(pdev, reg_base);
749 	pci_iounmap(pdev, cfg_base);
750 	pci_release_regions(pdev);
751 	pci_disable_device(pdev);
752 }
753 
754 static struct pci_driver peak_pci_driver = {
755 	.name = DRV_NAME,
756 	.id_table = peak_pci_tbl,
757 	.probe = peak_pci_probe,
758 	.remove = peak_pci_remove,
759 };
760 
761 module_pci_driver(peak_pci_driver);
762