xref: /linux/drivers/pci/hotplug/shpchp_ctrl.c (revision de2fe5e07d58424bc286fff3fd3c1b0bf933cd58)
1 /*
2  * Standard Hot Plug Controller Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  * Copyright (C) 2003-2004 Intel Corporation
8  *
9  * All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or (at
14  * your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
19  * NON INFRINGEMENT.  See the GNU General Public License for more
20  * details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
27  *
28  */
29 
30 #include <linux/module.h>
31 #include <linux/kernel.h>
32 #include <linux/types.h>
33 #include <linux/smp_lock.h>
34 #include <linux/pci.h>
35 #include <linux/workqueue.h>
36 #include "../pci.h"
37 #include "shpchp.h"
38 
39 static void interrupt_event_handler(void *data);
40 static int shpchp_enable_slot(struct slot *p_slot);
41 static int shpchp_disable_slot(struct slot *p_slot);
42 
43 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
44 {
45 	struct event_info *info;
46 
47 	info = kmalloc(sizeof(*info), GFP_ATOMIC);
48 	if (!info)
49 		return -ENOMEM;
50 
51 	info->event_type = event_type;
52 	info->p_slot = p_slot;
53 	INIT_WORK(&info->work, interrupt_event_handler, info);
54 
55 	schedule_work(&info->work);
56 
57 	return 0;
58 }
59 
60 u8 shpchp_handle_attention_button(u8 hp_slot, void *inst_id)
61 {
62 	struct controller *ctrl = (struct controller *) inst_id;
63 	struct slot *p_slot;
64 	u32 event_type;
65 
66 	/* Attention Button Change */
67 	dbg("shpchp:  Attention button interrupt received.\n");
68 
69 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
70 	p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
71 
72 	/*
73 	 *  Button pressed - See if need to TAKE ACTION!!!
74 	 */
75 	info("Button pressed on Slot(%d)\n", ctrl->first_slot + hp_slot);
76 	event_type = INT_BUTTON_PRESS;
77 
78 	queue_interrupt_event(p_slot, event_type);
79 
80 	return 0;
81 
82 }
83 
84 u8 shpchp_handle_switch_change(u8 hp_slot, void *inst_id)
85 {
86 	struct controller *ctrl = (struct controller *) inst_id;
87 	struct slot *p_slot;
88 	u8 getstatus;
89 	u32 event_type;
90 
91 	/* Switch Change */
92 	dbg("shpchp:  Switch interrupt received.\n");
93 
94 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
95 	p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
96 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
97 	dbg("%s: Card present %x Power status %x\n", __FUNCTION__,
98 		p_slot->presence_save, p_slot->pwr_save);
99 
100 	if (getstatus) {
101 		/*
102 		 * Switch opened
103 		 */
104 		info("Latch open on Slot(%d)\n", ctrl->first_slot + hp_slot);
105 		event_type = INT_SWITCH_OPEN;
106 		if (p_slot->pwr_save && p_slot->presence_save) {
107 			event_type = INT_POWER_FAULT;
108 			err("Surprise Removal of card\n");
109 		}
110 	} else {
111 		/*
112 		 *  Switch closed
113 		 */
114 		info("Latch close on Slot(%d)\n", ctrl->first_slot + hp_slot);
115 		event_type = INT_SWITCH_CLOSE;
116 	}
117 
118 	queue_interrupt_event(p_slot, event_type);
119 
120 	return 1;
121 }
122 
123 u8 shpchp_handle_presence_change(u8 hp_slot, void *inst_id)
124 {
125 	struct controller *ctrl = (struct controller *) inst_id;
126 	struct slot *p_slot;
127 	u32 event_type;
128 
129 	/* Presence Change */
130 	dbg("shpchp:  Presence/Notify input change.\n");
131 
132 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
133 
134 	/*
135 	 * Save the presence state
136 	 */
137 	p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
138 	if (p_slot->presence_save) {
139 		/*
140 		 * Card Present
141 		 */
142 		info("Card present on Slot(%d)\n", ctrl->first_slot + hp_slot);
143 		event_type = INT_PRESENCE_ON;
144 	} else {
145 		/*
146 		 * Not Present
147 		 */
148 		info("Card not present on Slot(%d)\n", ctrl->first_slot + hp_slot);
149 		event_type = INT_PRESENCE_OFF;
150 	}
151 
152 	queue_interrupt_event(p_slot, event_type);
153 
154 	return 1;
155 }
156 
157 u8 shpchp_handle_power_fault(u8 hp_slot, void *inst_id)
158 {
159 	struct controller *ctrl = (struct controller *) inst_id;
160 	struct slot *p_slot;
161 	u32 event_type;
162 
163 	/* Power fault */
164 	dbg("shpchp:  Power fault interrupt received.\n");
165 
166 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
167 
168 	if ( !(p_slot->hpc_ops->query_power_fault(p_slot))) {
169 		/*
170 		 * Power fault Cleared
171 		 */
172 		info("Power fault cleared on Slot(%d)\n", ctrl->first_slot + hp_slot);
173 		p_slot->status = 0x00;
174 		event_type = INT_POWER_FAULT_CLEAR;
175 	} else {
176 		/*
177 		 *   Power fault
178 		 */
179 		info("Power fault on Slot(%d)\n", ctrl->first_slot + hp_slot);
180 		event_type = INT_POWER_FAULT;
181 		/* set power fault status for this board */
182 		p_slot->status = 0xFF;
183 		info("power fault bit %x set\n", hp_slot);
184 	}
185 
186 	queue_interrupt_event(p_slot, event_type);
187 
188 	return 1;
189 }
190 
191 /* The following routines constitute the bulk of the
192    hotplug controller logic
193  */
194 static int change_bus_speed(struct controller *ctrl, struct slot *p_slot,
195 		enum pci_bus_speed speed)
196 {
197 	int rc = 0;
198 
199 	dbg("%s: change to speed %d\n", __FUNCTION__, speed);
200 	if ((rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, speed))) {
201 		err("%s: Issue of set bus speed mode command failed\n",
202 		    __FUNCTION__);
203 		return WRONG_BUS_FREQUENCY;
204 	}
205 	return rc;
206 }
207 
208 static int fix_bus_speed(struct controller *ctrl, struct slot *pslot,
209 		u8 flag, enum pci_bus_speed asp, enum pci_bus_speed bsp,
210 		enum pci_bus_speed msp)
211 {
212 	int rc = 0;
213 
214 	/*
215 	 * If other slots on the same bus are occupied, we cannot
216 	 * change the bus speed.
217 	 */
218 	if (flag) {
219 		if (asp < bsp) {
220 			err("%s: speed of bus %x and adapter %x mismatch\n",
221 			    __FUNCTION__, bsp, asp);
222 			rc = WRONG_BUS_FREQUENCY;
223 		}
224 		return rc;
225 	}
226 
227 	if (asp < msp) {
228 		if (bsp != asp)
229 			rc = change_bus_speed(ctrl, pslot, asp);
230 	} else {
231 		if (bsp != msp)
232 			rc = change_bus_speed(ctrl, pslot, msp);
233 	}
234 	return rc;
235 }
236 
237 /**
238  * board_added - Called after a board has been added to the system.
239  *
240  * Turns power on for the board
241  * Configures board
242  *
243  */
244 static int board_added(struct slot *p_slot)
245 {
246 	u8 hp_slot;
247 	u8 slots_not_empty = 0;
248 	int rc = 0;
249 	enum pci_bus_speed asp, bsp, msp;
250 	struct controller *ctrl = p_slot->ctrl;
251 
252 	hp_slot = p_slot->device - ctrl->slot_device_offset;
253 
254 	dbg("%s: p_slot->device, slot_offset, hp_slot = %d, %d ,%d\n",
255 			__FUNCTION__, p_slot->device,
256 			ctrl->slot_device_offset, hp_slot);
257 
258 	/* Power on slot without connecting to bus */
259 	rc = p_slot->hpc_ops->power_on_slot(p_slot);
260 	if (rc) {
261 		err("%s: Failed to power on slot\n", __FUNCTION__);
262 		return -1;
263 	}
264 
265 	if ((ctrl->pci_dev->vendor == 0x8086) && (ctrl->pci_dev->device == 0x0332)) {
266 		if (slots_not_empty)
267 			return WRONG_BUS_FREQUENCY;
268 
269 		if ((rc = p_slot->hpc_ops->set_bus_speed_mode(p_slot, PCI_SPEED_33MHz))) {
270 			err("%s: Issue of set bus speed mode command failed\n", __FUNCTION__);
271 			return WRONG_BUS_FREQUENCY;
272 		}
273 
274 		/* turn on board, blink green LED, turn off Amber LED */
275 		if ((rc = p_slot->hpc_ops->slot_enable(p_slot))) {
276 			err("%s: Issue of Slot Enable command failed\n", __FUNCTION__);
277 			return rc;
278 		}
279 	}
280 
281 	rc = p_slot->hpc_ops->get_adapter_speed(p_slot, &asp);
282 	if (rc) {
283 		err("%s: Can't get adapter speed or bus mode mismatch\n",
284 		    __FUNCTION__);
285 		return WRONG_BUS_FREQUENCY;
286 	}
287 
288 	rc = p_slot->hpc_ops->get_cur_bus_speed(p_slot, &bsp);
289 	if (rc) {
290 		err("%s: Can't get bus operation speed\n", __FUNCTION__);
291 		return WRONG_BUS_FREQUENCY;
292 	}
293 
294 	rc = p_slot->hpc_ops->get_max_bus_speed(p_slot, &msp);
295 	if (rc) {
296 		err("%s: Can't get max bus operation speed\n", __FUNCTION__);
297 		msp = bsp;
298 	}
299 
300 	/* Check if there are other slots or devices on the same bus */
301 	if (!list_empty(&ctrl->pci_dev->subordinate->devices))
302 		slots_not_empty = 1;
303 
304 	dbg("%s: slots_not_empty %d, adapter_speed %d, bus_speed %d, "
305 	    "max_bus_speed %d\n", __FUNCTION__, slots_not_empty, asp,
306 	    bsp, msp);
307 
308 	rc = fix_bus_speed(ctrl, p_slot, slots_not_empty, asp, bsp, msp);
309 	if (rc)
310 		return rc;
311 
312 	/* turn on board, blink green LED, turn off Amber LED */
313 	if ((rc = p_slot->hpc_ops->slot_enable(p_slot))) {
314 		err("%s: Issue of Slot Enable command failed\n", __FUNCTION__);
315 		return rc;
316 	}
317 
318 	/* Wait for ~1 second */
319 	msleep(1000);
320 
321 	dbg("%s: slot status = %x\n", __FUNCTION__, p_slot->status);
322 	/* Check for a power fault */
323 	if (p_slot->status == 0xFF) {
324 		/* power fault occurred, but it was benign */
325 		dbg("%s: power fault\n", __FUNCTION__);
326 		rc = POWER_FAILURE;
327 		p_slot->status = 0;
328 		goto err_exit;
329 	}
330 
331 	if (shpchp_configure_device(p_slot)) {
332 		err("Cannot add device at 0x%x:0x%x\n", p_slot->bus,
333 				p_slot->device);
334 		goto err_exit;
335 	}
336 
337 	p_slot->status = 0;
338 	p_slot->is_a_board = 0x01;
339 	p_slot->pwr_save = 1;
340 
341 	p_slot->hpc_ops->green_led_on(p_slot);
342 
343 	return 0;
344 
345 err_exit:
346 	/* turn off slot, turn on Amber LED, turn off Green LED */
347 	rc = p_slot->hpc_ops->slot_disable(p_slot);
348 	if (rc) {
349 		err("%s: Issue of Slot Disable command failed\n", __FUNCTION__);
350 		return rc;
351 	}
352 
353 	return(rc);
354 }
355 
356 
357 /**
358  * remove_board - Turns off slot and LED's
359  *
360  */
361 static int remove_board(struct slot *p_slot)
362 {
363 	struct controller *ctrl = p_slot->ctrl;
364 	u8 hp_slot;
365 	int rc;
366 
367 	if (shpchp_unconfigure_device(p_slot))
368 		return(1);
369 
370 	hp_slot = p_slot->device - ctrl->slot_device_offset;
371 	p_slot = shpchp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
372 
373 	dbg("In %s, hp_slot = %d\n", __FUNCTION__, hp_slot);
374 
375 	/* Change status to shutdown */
376 	if (p_slot->is_a_board)
377 		p_slot->status = 0x01;
378 
379 	/* turn off slot, turn on Amber LED, turn off Green LED */
380 	rc = p_slot->hpc_ops->slot_disable(p_slot);
381 	if (rc) {
382 		err("%s: Issue of Slot Disable command failed\n", __FUNCTION__);
383 		return rc;
384 	}
385 
386 	rc = p_slot->hpc_ops->set_attention_status(p_slot, 0);
387 	if (rc) {
388 		err("%s: Issue of Set Attention command failed\n", __FUNCTION__);
389 		return rc;
390 	}
391 
392 	p_slot->pwr_save = 0;
393 	p_slot->is_a_board = 0;
394 
395 	return 0;
396 }
397 
398 
399 struct pushbutton_work_info {
400 	struct slot *p_slot;
401 	struct work_struct work;
402 };
403 
404 /**
405  * shpchp_pushbutton_thread
406  *
407  * Scheduled procedure to handle blocking stuff for the pushbuttons
408  * Handles all pending events and exits.
409  *
410  */
411 static void shpchp_pushbutton_thread(void *data)
412 {
413 	struct pushbutton_work_info *info = data;
414 	struct slot *p_slot = info->p_slot;
415 
416 	mutex_lock(&p_slot->lock);
417 	switch (p_slot->state) {
418 	case POWEROFF_STATE:
419 		mutex_unlock(&p_slot->lock);
420 		shpchp_disable_slot(p_slot);
421 		mutex_lock(&p_slot->lock);
422 		p_slot->state = STATIC_STATE;
423 		break;
424 	case POWERON_STATE:
425 		mutex_unlock(&p_slot->lock);
426 		if (shpchp_enable_slot(p_slot))
427 			p_slot->hpc_ops->green_led_off(p_slot);
428 		mutex_lock(&p_slot->lock);
429 		p_slot->state = STATIC_STATE;
430 		break;
431 	default:
432 		break;
433 	}
434 	mutex_unlock(&p_slot->lock);
435 
436 	kfree(info);
437 }
438 
439 void queue_pushbutton_work(void *data)
440 {
441 	struct slot *p_slot = data;
442 	struct pushbutton_work_info *info;
443 
444 	info = kmalloc(sizeof(*info), GFP_KERNEL);
445 	if (!info) {
446 		err("%s: Cannot allocate memory\n", __FUNCTION__);
447 		return;
448 	}
449 	info->p_slot = p_slot;
450 	INIT_WORK(&info->work, shpchp_pushbutton_thread, info);
451 
452 	mutex_lock(&p_slot->lock);
453 	switch (p_slot->state) {
454 	case BLINKINGOFF_STATE:
455 		p_slot->state = POWEROFF_STATE;
456 		break;
457 	case BLINKINGON_STATE:
458 		p_slot->state = POWERON_STATE;
459 		break;
460 	default:
461 		goto out;
462 	}
463 	queue_work(shpchp_wq, &info->work);
464  out:
465 	mutex_unlock(&p_slot->lock);
466 }
467 
468 static int update_slot_info (struct slot *slot)
469 {
470 	struct hotplug_slot_info *info;
471 	int result;
472 
473 	info = kmalloc(sizeof(*info), GFP_KERNEL);
474 	if (!info)
475 		return -ENOMEM;
476 
477 	slot->hpc_ops->get_power_status(slot, &(info->power_status));
478 	slot->hpc_ops->get_attention_status(slot, &(info->attention_status));
479 	slot->hpc_ops->get_latch_status(slot, &(info->latch_status));
480 	slot->hpc_ops->get_adapter_status(slot, &(info->adapter_status));
481 
482 	result = pci_hp_change_slot_info(slot->hotplug_slot, info);
483 	kfree (info);
484 	return result;
485 }
486 
487 /*
488  * Note: This function must be called with slot->lock held
489  */
490 static void handle_button_press_event(struct slot *p_slot)
491 {
492 	u8 getstatus;
493 
494 	switch (p_slot->state) {
495 	case STATIC_STATE:
496 		p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
497 		if (getstatus) {
498 			p_slot->state = BLINKINGOFF_STATE;
499 			info(msg_button_off, p_slot->number);
500 		} else {
501 			p_slot->state = BLINKINGON_STATE;
502 			info(msg_button_on, p_slot->number);
503 		}
504 		/* blink green LED and turn off amber */
505 		p_slot->hpc_ops->green_led_blink(p_slot);
506 		p_slot->hpc_ops->set_attention_status(p_slot, 0);
507 
508 		schedule_delayed_work(&p_slot->work, 5*HZ);
509 		break;
510 	case BLINKINGOFF_STATE:
511 	case BLINKINGON_STATE:
512 		/*
513 		 * Cancel if we are still blinking; this means that we
514 		 * press the attention again before the 5 sec. limit
515 		 * expires to cancel hot-add or hot-remove
516 		 */
517 		info("Button cancel on Slot(%s)\n", p_slot->name);
518 		dbg("%s: button cancel\n", __FUNCTION__);
519 		cancel_delayed_work(&p_slot->work);
520 		if (p_slot->state == BLINKINGOFF_STATE)
521 			p_slot->hpc_ops->green_led_on(p_slot);
522 		else
523 			p_slot->hpc_ops->green_led_off(p_slot);
524 		p_slot->hpc_ops->set_attention_status(p_slot, 0);
525 		info(msg_button_cancel, p_slot->number);
526 		p_slot->state = STATIC_STATE;
527 		break;
528 	case POWEROFF_STATE:
529 	case POWERON_STATE:
530 		/*
531 		 * Ignore if the slot is on power-on or power-off state;
532 		 * this means that the previous attention button action
533 		 * to hot-add or hot-remove is undergoing
534 		 */
535 		info("Button ignore on Slot(%s)\n", p_slot->name);
536 		update_slot_info(p_slot);
537 		break;
538 	default:
539 		warn("Not a valid state\n");
540 		break;
541 	}
542 }
543 
544 static void interrupt_event_handler(void *data)
545 {
546 	struct event_info *info = data;
547 	struct slot *p_slot = info->p_slot;
548 
549 	mutex_lock(&p_slot->lock);
550 	switch (info->event_type) {
551 	case INT_BUTTON_PRESS:
552 		handle_button_press_event(p_slot);
553 		break;
554 	case INT_POWER_FAULT:
555 		dbg("%s: power fault\n", __FUNCTION__);
556 		p_slot->hpc_ops->set_attention_status(p_slot, 1);
557 		p_slot->hpc_ops->green_led_off(p_slot);
558 		break;
559 	default:
560 		update_slot_info(p_slot);
561 		break;
562 	}
563 	mutex_unlock(&p_slot->lock);
564 
565 	kfree(info);
566 }
567 
568 
569 static int shpchp_enable_slot (struct slot *p_slot)
570 {
571 	u8 getstatus = 0;
572 	int rc, retval = -ENODEV;
573 
574 	/* Check to see if (latch closed, card present, power off) */
575 	mutex_lock(&p_slot->ctrl->crit_sect);
576 	rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
577 	if (rc || !getstatus) {
578 		info("%s: no adapter on slot(%x)\n", __FUNCTION__, p_slot->number);
579 		goto out;
580 	}
581 	rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
582 	if (rc || getstatus) {
583 		info("%s: latch open on slot(%x)\n", __FUNCTION__, p_slot->number);
584 		goto out;
585 	}
586 	rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
587 	if (rc || getstatus) {
588 		info("%s: already enabled on slot(%x)\n", __FUNCTION__, p_slot->number);
589 		goto out;
590 	}
591 
592 	p_slot->is_a_board = 1;
593 
594 	/* We have to save the presence info for these slots */
595 	p_slot->hpc_ops->get_adapter_status(p_slot, &(p_slot->presence_save));
596 	p_slot->hpc_ops->get_power_status(p_slot, &(p_slot->pwr_save));
597 	dbg("%s: p_slot->pwr_save %x\n", __FUNCTION__, p_slot->pwr_save);
598 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
599 
600 	if(((p_slot->ctrl->pci_dev->vendor == PCI_VENDOR_ID_AMD) ||
601 	    (p_slot->ctrl->pci_dev->device == PCI_DEVICE_ID_AMD_POGO_7458))
602 	     && p_slot->ctrl->num_slots == 1) {
603 		/* handle amd pogo errata; this must be done before enable  */
604 		amd_pogo_errata_save_misc_reg(p_slot);
605 		retval = board_added(p_slot);
606 		/* handle amd pogo errata; this must be done after enable  */
607 		amd_pogo_errata_restore_misc_reg(p_slot);
608 	} else
609 		retval = board_added(p_slot);
610 
611 	if (retval) {
612 		p_slot->hpc_ops->get_adapter_status(p_slot,
613 				&(p_slot->presence_save));
614 		p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
615 	}
616 
617 	update_slot_info(p_slot);
618  out:
619 	mutex_unlock(&p_slot->ctrl->crit_sect);
620 	return retval;
621 }
622 
623 
624 static int shpchp_disable_slot (struct slot *p_slot)
625 {
626 	u8 getstatus = 0;
627 	int rc, retval = -ENODEV;
628 
629 	if (!p_slot->ctrl)
630 		return -ENODEV;
631 
632 	/* Check to see if (latch closed, card present, power on) */
633 	mutex_lock(&p_slot->ctrl->crit_sect);
634 
635 	rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
636 	if (rc || !getstatus) {
637 		info("%s: no adapter on slot(%x)\n", __FUNCTION__, p_slot->number);
638 		goto out;
639 	}
640 	rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
641 	if (rc || getstatus) {
642 		info("%s: latch open on slot(%x)\n", __FUNCTION__, p_slot->number);
643 		goto out;
644 	}
645 	rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
646 	if (rc || !getstatus) {
647 		info("%s: already disabled slot(%x)\n", __FUNCTION__, p_slot->number);
648 		goto out;
649 	}
650 
651 	retval = remove_board(p_slot);
652 	update_slot_info(p_slot);
653  out:
654 	mutex_unlock(&p_slot->ctrl->crit_sect);
655 	return retval;
656 }
657 
658 int shpchp_sysfs_enable_slot(struct slot *p_slot)
659 {
660 	int retval = -ENODEV;
661 
662 	mutex_lock(&p_slot->lock);
663 	switch (p_slot->state) {
664 	case BLINKINGON_STATE:
665 		cancel_delayed_work(&p_slot->work);
666 	case STATIC_STATE:
667 		p_slot->state = POWERON_STATE;
668 		mutex_unlock(&p_slot->lock);
669 		retval = shpchp_enable_slot(p_slot);
670 		mutex_lock(&p_slot->lock);
671 		p_slot->state = STATIC_STATE;
672 		break;
673 	case POWERON_STATE:
674 		info("Slot %s is already in powering on state\n",
675 		     p_slot->name);
676 		break;
677 	case BLINKINGOFF_STATE:
678 	case POWEROFF_STATE:
679 		info("Already enabled on slot %s\n", p_slot->name);
680 		break;
681 	default:
682 		err("Not a valid state on slot %s\n", p_slot->name);
683 		break;
684 	}
685 	mutex_unlock(&p_slot->lock);
686 
687 	return retval;
688 }
689 
690 int shpchp_sysfs_disable_slot(struct slot *p_slot)
691 {
692 	int retval = -ENODEV;
693 
694 	mutex_lock(&p_slot->lock);
695 	switch (p_slot->state) {
696 	case BLINKINGOFF_STATE:
697 		cancel_delayed_work(&p_slot->work);
698 	case STATIC_STATE:
699 		p_slot->state = POWEROFF_STATE;
700 		mutex_unlock(&p_slot->lock);
701 		retval = shpchp_disable_slot(p_slot);
702 		mutex_lock(&p_slot->lock);
703 		p_slot->state = STATIC_STATE;
704 		break;
705 	case POWEROFF_STATE:
706 		info("Slot %s is already in powering off state\n",
707 		     p_slot->name);
708 		break;
709 	case BLINKINGON_STATE:
710 	case POWERON_STATE:
711 		info("Already disabled on slot %s\n", p_slot->name);
712 		break;
713 	default:
714 		err("Not a valid state on slot %s\n", p_slot->name);
715 		break;
716 	}
717 	mutex_unlock(&p_slot->lock);
718 
719 	return retval;
720 }
721