xref: /openbmc/linux/drivers/misc/hpilo.c (revision 367b8112)
1 /*
2  * Driver for HP iLO/iLO2 management processor.
3  *
4  * Copyright (C) 2008 Hewlett-Packard Development Company, L.P.
5  *	David Altobelli <david.altobelli@hp.com>
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  */
11 #include <linux/kernel.h>
12 #include <linux/types.h>
13 #include <linux/module.h>
14 #include <linux/fs.h>
15 #include <linux/pci.h>
16 #include <linux/ioport.h>
17 #include <linux/device.h>
18 #include <linux/file.h>
19 #include <linux/cdev.h>
20 #include <linux/spinlock.h>
21 #include <linux/delay.h>
22 #include <linux/uaccess.h>
23 #include <linux/io.h>
24 #include "hpilo.h"
25 
26 static struct class *ilo_class;
27 static unsigned int ilo_major;
28 static char ilo_hwdev[MAX_ILO_DEV];
29 
30 static inline int get_entry_id(int entry)
31 {
32 	return (entry & ENTRY_MASK_DESCRIPTOR) >> ENTRY_BITPOS_DESCRIPTOR;
33 }
34 
35 static inline int get_entry_len(int entry)
36 {
37 	return ((entry & ENTRY_MASK_QWORDS) >> ENTRY_BITPOS_QWORDS) << 3;
38 }
39 
40 static inline int mk_entry(int id, int len)
41 {
42 	int qlen = len & 7 ? (len >> 3) + 1 : len >> 3;
43 	return id << ENTRY_BITPOS_DESCRIPTOR | qlen << ENTRY_BITPOS_QWORDS;
44 }
45 
46 static inline int desc_mem_sz(int nr_entry)
47 {
48 	return nr_entry << L2_QENTRY_SZ;
49 }
50 
51 /*
52  * FIFO queues, shared with hardware.
53  *
54  * If a queue has empty slots, an entry is added to the queue tail,
55  * and that entry is marked as occupied.
56  * Entries can be dequeued from the head of the list, when the device
57  * has marked the entry as consumed.
58  *
59  * Returns true on successful queue/dequeue, false on failure.
60  */
61 static int fifo_enqueue(struct ilo_hwinfo *hw, char *fifobar, int entry)
62 {
63 	struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
64 	int ret = 0;
65 
66 	spin_lock(&hw->fifo_lock);
67 	if (!(fifo_q->fifobar[(fifo_q->tail + 1) & fifo_q->imask]
68 	      & ENTRY_MASK_O)) {
69 		fifo_q->fifobar[fifo_q->tail & fifo_q->imask] |=
70 				(entry & ENTRY_MASK_NOSTATE) | fifo_q->merge;
71 		fifo_q->tail += 1;
72 		ret = 1;
73 	}
74 	spin_unlock(&hw->fifo_lock);
75 
76 	return ret;
77 }
78 
79 static int fifo_dequeue(struct ilo_hwinfo *hw, char *fifobar, int *entry)
80 {
81 	struct fifo *fifo_q = FIFOBARTOHANDLE(fifobar);
82 	int ret = 0;
83 	u64 c;
84 
85 	spin_lock(&hw->fifo_lock);
86 	c = fifo_q->fifobar[fifo_q->head & fifo_q->imask];
87 	if (c & ENTRY_MASK_C) {
88 		if (entry)
89 			*entry = c & ENTRY_MASK_NOSTATE;
90 
91 		fifo_q->fifobar[fifo_q->head & fifo_q->imask] =
92 							(c | ENTRY_MASK) + 1;
93 		fifo_q->head += 1;
94 		ret = 1;
95 	}
96 	spin_unlock(&hw->fifo_lock);
97 
98 	return ret;
99 }
100 
101 static int ilo_pkt_enqueue(struct ilo_hwinfo *hw, struct ccb *ccb,
102 			   int dir, int id, int len)
103 {
104 	char *fifobar;
105 	int entry;
106 
107 	if (dir == SENDQ)
108 		fifobar = ccb->ccb_u1.send_fifobar;
109 	else
110 		fifobar = ccb->ccb_u3.recv_fifobar;
111 
112 	entry = mk_entry(id, len);
113 	return fifo_enqueue(hw, fifobar, entry);
114 }
115 
116 static int ilo_pkt_dequeue(struct ilo_hwinfo *hw, struct ccb *ccb,
117 			   int dir, int *id, int *len, void **pkt)
118 {
119 	char *fifobar, *desc;
120 	int entry = 0, pkt_id = 0;
121 	int ret;
122 
123 	if (dir == SENDQ) {
124 		fifobar = ccb->ccb_u1.send_fifobar;
125 		desc = ccb->ccb_u2.send_desc;
126 	} else {
127 		fifobar = ccb->ccb_u3.recv_fifobar;
128 		desc = ccb->ccb_u4.recv_desc;
129 	}
130 
131 	ret = fifo_dequeue(hw, fifobar, &entry);
132 	if (ret) {
133 		pkt_id = get_entry_id(entry);
134 		if (id)
135 			*id = pkt_id;
136 		if (len)
137 			*len = get_entry_len(entry);
138 		if (pkt)
139 			*pkt = (void *)(desc + desc_mem_sz(pkt_id));
140 	}
141 
142 	return ret;
143 }
144 
145 static inline void doorbell_set(struct ccb *ccb)
146 {
147 	iowrite8(1, ccb->ccb_u5.db_base);
148 }
149 
150 static inline void doorbell_clr(struct ccb *ccb)
151 {
152 	iowrite8(2, ccb->ccb_u5.db_base);
153 }
154 static inline int ctrl_set(int l2sz, int idxmask, int desclim)
155 {
156 	int active = 0, go = 1;
157 	return l2sz << CTRL_BITPOS_L2SZ |
158 	       idxmask << CTRL_BITPOS_FIFOINDEXMASK |
159 	       desclim << CTRL_BITPOS_DESCLIMIT |
160 	       active << CTRL_BITPOS_A |
161 	       go << CTRL_BITPOS_G;
162 }
163 static void ctrl_setup(struct ccb *ccb, int nr_desc, int l2desc_sz)
164 {
165 	/* for simplicity, use the same parameters for send and recv ctrls */
166 	ccb->send_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
167 	ccb->recv_ctrl = ctrl_set(l2desc_sz, nr_desc-1, nr_desc-1);
168 }
169 
170 static inline int fifo_sz(int nr_entry)
171 {
172 	/* size of a fifo is determined by the number of entries it contains */
173 	return (nr_entry * sizeof(u64)) + FIFOHANDLESIZE;
174 }
175 
176 static void fifo_setup(void *base_addr, int nr_entry)
177 {
178 	struct fifo *fifo_q = base_addr;
179 	int i;
180 
181 	/* set up an empty fifo */
182 	fifo_q->head = 0;
183 	fifo_q->tail = 0;
184 	fifo_q->reset = 0;
185 	fifo_q->nrents = nr_entry;
186 	fifo_q->imask = nr_entry - 1;
187 	fifo_q->merge = ENTRY_MASK_O;
188 
189 	for (i = 0; i < nr_entry; i++)
190 		fifo_q->fifobar[i] = 0;
191 }
192 
193 static void ilo_ccb_close(struct pci_dev *pdev, struct ccb_data *data)
194 {
195 	struct ccb *driver_ccb;
196 	struct ccb __iomem *device_ccb;
197 	int retries;
198 
199 	driver_ccb = &data->driver_ccb;
200 	device_ccb = data->mapped_ccb;
201 
202 	/* complicated dance to tell the hw we are stopping */
203 	doorbell_clr(driver_ccb);
204 	iowrite32(ioread32(&device_ccb->send_ctrl) & ~(1 << CTRL_BITPOS_G),
205 		  &device_ccb->send_ctrl);
206 	iowrite32(ioread32(&device_ccb->recv_ctrl) & ~(1 << CTRL_BITPOS_G),
207 		  &device_ccb->recv_ctrl);
208 
209 	/* give iLO some time to process stop request */
210 	for (retries = 1000; retries > 0; retries--) {
211 		doorbell_set(driver_ccb);
212 		udelay(1);
213 		if (!(ioread32(&device_ccb->send_ctrl) & (1 << CTRL_BITPOS_A))
214 		    &&
215 		    !(ioread32(&device_ccb->recv_ctrl) & (1 << CTRL_BITPOS_A)))
216 			break;
217 	}
218 	if (retries == 0)
219 		dev_err(&pdev->dev, "Closing, but controller still active\n");
220 
221 	/* clear the hw ccb */
222 	memset_io(device_ccb, 0, sizeof(struct ccb));
223 
224 	/* free resources used to back send/recv queues */
225 	pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
226 }
227 
228 static int ilo_ccb_open(struct ilo_hwinfo *hw, struct ccb_data *data, int slot)
229 {
230 	char *dma_va, *dma_pa;
231 	int pkt_id, pkt_sz, i, error;
232 	struct ccb *driver_ccb, *ilo_ccb;
233 	struct pci_dev *pdev;
234 
235 	driver_ccb = &data->driver_ccb;
236 	ilo_ccb = &data->ilo_ccb;
237 	pdev = hw->ilo_dev;
238 
239 	data->dma_size = 2 * fifo_sz(NR_QENTRY) +
240 			 2 * desc_mem_sz(NR_QENTRY) +
241 			 ILO_START_ALIGN + ILO_CACHE_SZ;
242 
243 	error = -ENOMEM;
244 	data->dma_va = pci_alloc_consistent(pdev, data->dma_size,
245 					    &data->dma_pa);
246 	if (!data->dma_va)
247 		goto out;
248 
249 	dma_va = (char *)data->dma_va;
250 	dma_pa = (char *)data->dma_pa;
251 
252 	memset(dma_va, 0, data->dma_size);
253 
254 	dma_va = (char *)roundup((unsigned long)dma_va, ILO_START_ALIGN);
255 	dma_pa = (char *)roundup((unsigned long)dma_pa, ILO_START_ALIGN);
256 
257 	/*
258 	 * Create two ccb's, one with virt addrs, one with phys addrs.
259 	 * Copy the phys addr ccb to device shared mem.
260 	 */
261 	ctrl_setup(driver_ccb, NR_QENTRY, L2_QENTRY_SZ);
262 	ctrl_setup(ilo_ccb, NR_QENTRY, L2_QENTRY_SZ);
263 
264 	fifo_setup(dma_va, NR_QENTRY);
265 	driver_ccb->ccb_u1.send_fifobar = dma_va + FIFOHANDLESIZE;
266 	ilo_ccb->ccb_u1.send_fifobar = dma_pa + FIFOHANDLESIZE;
267 	dma_va += fifo_sz(NR_QENTRY);
268 	dma_pa += fifo_sz(NR_QENTRY);
269 
270 	dma_va = (char *)roundup((unsigned long)dma_va, ILO_CACHE_SZ);
271 	dma_pa = (char *)roundup((unsigned long)dma_pa, ILO_CACHE_SZ);
272 
273 	fifo_setup(dma_va, NR_QENTRY);
274 	driver_ccb->ccb_u3.recv_fifobar = dma_va + FIFOHANDLESIZE;
275 	ilo_ccb->ccb_u3.recv_fifobar = dma_pa + FIFOHANDLESIZE;
276 	dma_va += fifo_sz(NR_QENTRY);
277 	dma_pa += fifo_sz(NR_QENTRY);
278 
279 	driver_ccb->ccb_u2.send_desc = dma_va;
280 	ilo_ccb->ccb_u2.send_desc = dma_pa;
281 	dma_pa += desc_mem_sz(NR_QENTRY);
282 	dma_va += desc_mem_sz(NR_QENTRY);
283 
284 	driver_ccb->ccb_u4.recv_desc = dma_va;
285 	ilo_ccb->ccb_u4.recv_desc = dma_pa;
286 
287 	driver_ccb->channel = slot;
288 	ilo_ccb->channel = slot;
289 
290 	driver_ccb->ccb_u5.db_base = hw->db_vaddr + (slot << L2_DB_SIZE);
291 	ilo_ccb->ccb_u5.db_base = NULL; /* hw ccb's doorbell is not used */
292 
293 	/* copy the ccb with physical addrs to device memory */
294 	data->mapped_ccb = (struct ccb __iomem *)
295 				(hw->ram_vaddr + (slot * ILOHW_CCB_SZ));
296 	memcpy_toio(data->mapped_ccb, ilo_ccb, sizeof(struct ccb));
297 
298 	/* put packets on the send and receive queues */
299 	pkt_sz = 0;
300 	for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++) {
301 		ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, pkt_sz);
302 		doorbell_set(driver_ccb);
303 	}
304 
305 	pkt_sz = desc_mem_sz(1);
306 	for (pkt_id = 0; pkt_id < NR_QENTRY; pkt_id++)
307 		ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, pkt_sz);
308 
309 	doorbell_clr(driver_ccb);
310 
311 	/* make sure iLO is really handling requests */
312 	for (i = 1000; i > 0; i--) {
313 		if (ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, NULL, NULL))
314 			break;
315 		udelay(1);
316 	}
317 
318 	if (i) {
319 		ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, 0);
320 		doorbell_set(driver_ccb);
321 	} else {
322 		dev_err(&pdev->dev, "Open could not dequeue a packet\n");
323 		error = -EBUSY;
324 		goto free;
325 	}
326 
327 	return 0;
328 free:
329 	pci_free_consistent(pdev, data->dma_size, data->dma_va, data->dma_pa);
330 out:
331 	return error;
332 }
333 
334 static inline int is_channel_reset(struct ccb *ccb)
335 {
336 	/* check for this particular channel needing a reset */
337 	return FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset;
338 }
339 
340 static inline void set_channel_reset(struct ccb *ccb)
341 {
342 	/* set a flag indicating this channel needs a reset */
343 	FIFOBARTOHANDLE(ccb->ccb_u1.send_fifobar)->reset = 1;
344 }
345 
346 static inline int is_device_reset(struct ilo_hwinfo *hw)
347 {
348 	/* check for global reset condition */
349 	return ioread32(&hw->mmio_vaddr[DB_OUT]) & (1 << DB_RESET);
350 }
351 
352 static inline void clear_device(struct ilo_hwinfo *hw)
353 {
354 	/* clear the device (reset bits, pending channel entries) */
355 	iowrite32(-1, &hw->mmio_vaddr[DB_OUT]);
356 }
357 
358 static void ilo_locked_reset(struct ilo_hwinfo *hw)
359 {
360 	int slot;
361 
362 	/*
363 	 * Mapped memory is zeroed on ilo reset, so set a per ccb flag
364 	 * to indicate that this ccb needs to be closed and reopened.
365 	 */
366 	for (slot = 0; slot < MAX_CCB; slot++) {
367 		if (!hw->ccb_alloc[slot])
368 			continue;
369 		set_channel_reset(&hw->ccb_alloc[slot]->driver_ccb);
370 	}
371 
372 	clear_device(hw);
373 }
374 
375 static void ilo_reset(struct ilo_hwinfo *hw)
376 {
377 	spin_lock(&hw->alloc_lock);
378 
379 	/* reset might have been handled after lock was taken */
380 	if (is_device_reset(hw))
381 		ilo_locked_reset(hw);
382 
383 	spin_unlock(&hw->alloc_lock);
384 }
385 
386 static ssize_t ilo_read(struct file *fp, char __user *buf,
387 			size_t len, loff_t *off)
388 {
389 	int err, found, cnt, pkt_id, pkt_len;
390 	struct ccb_data *data;
391 	struct ccb *driver_ccb;
392 	struct ilo_hwinfo *hw;
393 	void *pkt;
394 
395 	data = fp->private_data;
396 	driver_ccb = &data->driver_ccb;
397 	hw = data->ilo_hw;
398 
399 	if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
400 		/*
401 		 * If the device has been reset, applications
402 		 * need to close and reopen all ccbs.
403 		 */
404 		ilo_reset(hw);
405 		return -ENODEV;
406 	}
407 
408 	/*
409 	 * This function is to be called when data is expected
410 	 * in the channel, and will return an error if no packet is found
411 	 * during the loop below.  The sleep/retry logic is to allow
412 	 * applications to call read() immediately post write(),
413 	 * and give iLO some time to process the sent packet.
414 	 */
415 	cnt = 20;
416 	do {
417 		/* look for a received packet */
418 		found = ilo_pkt_dequeue(hw, driver_ccb, RECVQ, &pkt_id,
419 					&pkt_len, &pkt);
420 		if (found)
421 			break;
422 		cnt--;
423 		msleep(100);
424 	} while (!found && cnt);
425 
426 	if (!found)
427 		return -EAGAIN;
428 
429 	/* only copy the length of the received packet */
430 	if (pkt_len < len)
431 		len = pkt_len;
432 
433 	err = copy_to_user(buf, pkt, len);
434 
435 	/* return the received packet to the queue */
436 	ilo_pkt_enqueue(hw, driver_ccb, RECVQ, pkt_id, desc_mem_sz(1));
437 
438 	return err ? -EFAULT : len;
439 }
440 
441 static ssize_t ilo_write(struct file *fp, const char __user *buf,
442 			 size_t len, loff_t *off)
443 {
444 	int err, pkt_id, pkt_len;
445 	struct ccb_data *data;
446 	struct ccb *driver_ccb;
447 	struct ilo_hwinfo *hw;
448 	void *pkt;
449 
450 	data = fp->private_data;
451 	driver_ccb = &data->driver_ccb;
452 	hw = data->ilo_hw;
453 
454 	if (is_device_reset(hw) || is_channel_reset(driver_ccb)) {
455 		/*
456 		 * If the device has been reset, applications
457 		 * need to close and reopen all ccbs.
458 		 */
459 		ilo_reset(hw);
460 		return -ENODEV;
461 	}
462 
463 	/* get a packet to send the user command */
464 	if (!ilo_pkt_dequeue(hw, driver_ccb, SENDQ, &pkt_id, &pkt_len, &pkt))
465 		return -EBUSY;
466 
467 	/* limit the length to the length of the packet */
468 	if (pkt_len < len)
469 		len = pkt_len;
470 
471 	/* on failure, set the len to 0 to return empty packet to the device */
472 	err = copy_from_user(pkt, buf, len);
473 	if (err)
474 		len = 0;
475 
476 	/* send the packet */
477 	ilo_pkt_enqueue(hw, driver_ccb, SENDQ, pkt_id, len);
478 	doorbell_set(driver_ccb);
479 
480 	return err ? -EFAULT : len;
481 }
482 
483 static int ilo_close(struct inode *ip, struct file *fp)
484 {
485 	int slot;
486 	struct ccb_data *data;
487 	struct ilo_hwinfo *hw;
488 
489 	slot = iminor(ip) % MAX_CCB;
490 	hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
491 
492 	spin_lock(&hw->alloc_lock);
493 
494 	if (is_device_reset(hw))
495 		ilo_locked_reset(hw);
496 
497 	if (hw->ccb_alloc[slot]->ccb_cnt == 1) {
498 
499 		data = fp->private_data;
500 
501 		ilo_ccb_close(hw->ilo_dev, data);
502 
503 		kfree(data);
504 		hw->ccb_alloc[slot] = NULL;
505 	} else
506 		hw->ccb_alloc[slot]->ccb_cnt--;
507 
508 	spin_unlock(&hw->alloc_lock);
509 
510 	return 0;
511 }
512 
513 static int ilo_open(struct inode *ip, struct file *fp)
514 {
515 	int slot, error;
516 	struct ccb_data *data;
517 	struct ilo_hwinfo *hw;
518 
519 	slot = iminor(ip) % MAX_CCB;
520 	hw = container_of(ip->i_cdev, struct ilo_hwinfo, cdev);
521 
522 	/* new ccb allocation */
523 	data = kzalloc(sizeof(*data), GFP_KERNEL);
524 	if (!data)
525 		return -ENOMEM;
526 
527 	spin_lock(&hw->alloc_lock);
528 
529 	if (is_device_reset(hw))
530 		ilo_locked_reset(hw);
531 
532 	/* each fd private_data holds sw/hw view of ccb */
533 	if (hw->ccb_alloc[slot] == NULL) {
534 		/* create a channel control block for this minor */
535 		error = ilo_ccb_open(hw, data, slot);
536 		if (!error) {
537 			hw->ccb_alloc[slot] = data;
538 			hw->ccb_alloc[slot]->ccb_cnt = 1;
539 			hw->ccb_alloc[slot]->ccb_excl = fp->f_flags & O_EXCL;
540 			hw->ccb_alloc[slot]->ilo_hw = hw;
541 		} else
542 			kfree(data);
543 	} else {
544 		kfree(data);
545 		if (fp->f_flags & O_EXCL || hw->ccb_alloc[slot]->ccb_excl) {
546 			/*
547 			 * The channel exists, and either this open
548 			 * or a previous open of this channel wants
549 			 * exclusive access.
550 			 */
551 			error = -EBUSY;
552 		} else {
553 			hw->ccb_alloc[slot]->ccb_cnt++;
554 			error = 0;
555 		}
556 	}
557 	spin_unlock(&hw->alloc_lock);
558 
559 	if (!error)
560 		fp->private_data = hw->ccb_alloc[slot];
561 
562 	return error;
563 }
564 
565 static const struct file_operations ilo_fops = {
566 	.owner		= THIS_MODULE,
567 	.read		= ilo_read,
568 	.write		= ilo_write,
569 	.open 		= ilo_open,
570 	.release 	= ilo_close,
571 };
572 
573 static void ilo_unmap_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
574 {
575 	pci_iounmap(pdev, hw->db_vaddr);
576 	pci_iounmap(pdev, hw->ram_vaddr);
577 	pci_iounmap(pdev, hw->mmio_vaddr);
578 }
579 
580 static int __devinit ilo_map_device(struct pci_dev *pdev, struct ilo_hwinfo *hw)
581 {
582 	int error = -ENOMEM;
583 
584 	/* map the memory mapped i/o registers */
585 	hw->mmio_vaddr = pci_iomap(pdev, 1, 0);
586 	if (hw->mmio_vaddr == NULL) {
587 		dev_err(&pdev->dev, "Error mapping mmio\n");
588 		goto out;
589 	}
590 
591 	/* map the adapter shared memory region */
592 	hw->ram_vaddr = pci_iomap(pdev, 2, MAX_CCB * ILOHW_CCB_SZ);
593 	if (hw->ram_vaddr == NULL) {
594 		dev_err(&pdev->dev, "Error mapping shared mem\n");
595 		goto mmio_free;
596 	}
597 
598 	/* map the doorbell aperture */
599 	hw->db_vaddr = pci_iomap(pdev, 3, MAX_CCB * ONE_DB_SIZE);
600 	if (hw->db_vaddr == NULL) {
601 		dev_err(&pdev->dev, "Error mapping doorbell\n");
602 		goto ram_free;
603 	}
604 
605 	return 0;
606 ram_free:
607 	pci_iounmap(pdev, hw->ram_vaddr);
608 mmio_free:
609 	pci_iounmap(pdev, hw->mmio_vaddr);
610 out:
611 	return error;
612 }
613 
614 static void ilo_remove(struct pci_dev *pdev)
615 {
616 	int i, minor;
617 	struct ilo_hwinfo *ilo_hw = pci_get_drvdata(pdev);
618 
619 	clear_device(ilo_hw);
620 
621 	minor = MINOR(ilo_hw->cdev.dev);
622 	for (i = minor; i < minor + MAX_CCB; i++)
623 		device_destroy(ilo_class, MKDEV(ilo_major, i));
624 
625 	cdev_del(&ilo_hw->cdev);
626 	ilo_unmap_device(pdev, ilo_hw);
627 	pci_release_regions(pdev);
628 	pci_disable_device(pdev);
629 	kfree(ilo_hw);
630 	ilo_hwdev[(minor / MAX_CCB)] = 0;
631 }
632 
633 static int __devinit ilo_probe(struct pci_dev *pdev,
634 			       const struct pci_device_id *ent)
635 {
636 	int devnum, minor, start, error;
637 	struct ilo_hwinfo *ilo_hw;
638 
639 	/* find a free range for device files */
640 	for (devnum = 0; devnum < MAX_ILO_DEV; devnum++) {
641 		if (ilo_hwdev[devnum] == 0) {
642 			ilo_hwdev[devnum] = 1;
643 			break;
644 		}
645 	}
646 
647 	if (devnum == MAX_ILO_DEV) {
648 		dev_err(&pdev->dev, "Error finding free device\n");
649 		return -ENODEV;
650 	}
651 
652 	/* track global allocations for this device */
653 	error = -ENOMEM;
654 	ilo_hw = kzalloc(sizeof(*ilo_hw), GFP_KERNEL);
655 	if (!ilo_hw)
656 		goto out;
657 
658 	ilo_hw->ilo_dev = pdev;
659 	spin_lock_init(&ilo_hw->alloc_lock);
660 	spin_lock_init(&ilo_hw->fifo_lock);
661 
662 	error = pci_enable_device(pdev);
663 	if (error)
664 		goto free;
665 
666 	pci_set_master(pdev);
667 
668 	error = pci_request_regions(pdev, ILO_NAME);
669 	if (error)
670 		goto disable;
671 
672 	error = ilo_map_device(pdev, ilo_hw);
673 	if (error)
674 		goto free_regions;
675 
676 	pci_set_drvdata(pdev, ilo_hw);
677 	clear_device(ilo_hw);
678 
679 	cdev_init(&ilo_hw->cdev, &ilo_fops);
680 	ilo_hw->cdev.owner = THIS_MODULE;
681 	start = devnum * MAX_CCB;
682 	error = cdev_add(&ilo_hw->cdev, MKDEV(ilo_major, start), MAX_CCB);
683 	if (error) {
684 		dev_err(&pdev->dev, "Could not add cdev\n");
685 		goto unmap;
686 	}
687 
688 	for (minor = 0 ; minor < MAX_CCB; minor++) {
689 		struct device *dev;
690 		dev = device_create(ilo_class, &pdev->dev,
691 				    MKDEV(ilo_major, minor), NULL,
692 				    "hpilo!d%dccb%d", devnum, minor);
693 		if (IS_ERR(dev))
694 			dev_err(&pdev->dev, "Could not create files\n");
695 	}
696 
697 	return 0;
698 unmap:
699 	ilo_unmap_device(pdev, ilo_hw);
700 free_regions:
701 	pci_release_regions(pdev);
702 disable:
703 	pci_disable_device(pdev);
704 free:
705 	kfree(ilo_hw);
706 out:
707 	ilo_hwdev[devnum] = 0;
708 	return error;
709 }
710 
711 static struct pci_device_id ilo_devices[] = {
712 	{ PCI_DEVICE(PCI_VENDOR_ID_COMPAQ, 0xB204) },
713 	{ }
714 };
715 MODULE_DEVICE_TABLE(pci, ilo_devices);
716 
717 static struct pci_driver ilo_driver = {
718 	.name 	  = ILO_NAME,
719 	.id_table = ilo_devices,
720 	.probe 	  = ilo_probe,
721 	.remove   = __devexit_p(ilo_remove),
722 };
723 
724 static int __init ilo_init(void)
725 {
726 	int error;
727 	dev_t dev;
728 
729 	ilo_class = class_create(THIS_MODULE, "iLO");
730 	if (IS_ERR(ilo_class)) {
731 		error = PTR_ERR(ilo_class);
732 		goto out;
733 	}
734 
735 	error = alloc_chrdev_region(&dev, 0, MAX_OPEN, ILO_NAME);
736 	if (error)
737 		goto class_destroy;
738 
739 	ilo_major = MAJOR(dev);
740 
741 	error =	pci_register_driver(&ilo_driver);
742 	if (error)
743 		goto chr_remove;
744 
745 	return 0;
746 chr_remove:
747 	unregister_chrdev_region(dev, MAX_OPEN);
748 class_destroy:
749 	class_destroy(ilo_class);
750 out:
751 	return error;
752 }
753 
754 static void __exit ilo_exit(void)
755 {
756 	pci_unregister_driver(&ilo_driver);
757 	unregister_chrdev_region(MKDEV(ilo_major, 0), MAX_OPEN);
758 	class_destroy(ilo_class);
759 }
760 
761 MODULE_VERSION("0.05");
762 MODULE_ALIAS(ILO_NAME);
763 MODULE_DESCRIPTION(ILO_NAME);
764 MODULE_AUTHOR("David Altobelli <david.altobelli@hp.com>");
765 MODULE_LICENSE("GPL v2");
766 
767 module_init(ilo_init);
768 module_exit(ilo_exit);
769