Linux Audio

Check our new training course

In-person Linux kernel drivers training

Jun 16-20, 2025
Register
Loading...
v5.4
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * PCI Express Hot Plug Controller Driver
  4 *
  5 * Copyright (C) 1995,2001 Compaq Computer Corporation
  6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
  7 * Copyright (C) 2001 IBM Corp.
  8 * Copyright (C) 2003-2004 Intel Corporation
  9 *
 10 * All rights reserved.
 11 *
 12 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
 13 *
 14 */
 15
 16#define dev_fmt(fmt) "pciehp: " fmt
 17
 18#include <linux/kernel.h>
 19#include <linux/types.h>
 20#include <linux/pm_runtime.h>
 21#include <linux/pci.h>
 22#include "pciehp.h"
 23
 24/* The following routines constitute the bulk of the
 25   hotplug controller logic
 26 */
 27
 28#define SAFE_REMOVAL	 true
 29#define SURPRISE_REMOVAL false
 30
 31static void set_slot_off(struct controller *ctrl)
 32{
 33	/*
 34	 * Turn off slot, turn on attention indicator, turn off power
 35	 * indicator
 36	 */
 37	if (POWER_CTRL(ctrl)) {
 38		pciehp_power_off_slot(ctrl);
 39
 40		/*
 41		 * After turning power off, we must wait for at least 1 second
 42		 * before taking any action that relies on power having been
 43		 * removed from the slot/adapter.
 44		 */
 45		msleep(1000);
 46	}
 47
 48	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
 49			      PCI_EXP_SLTCTL_ATTN_IND_ON);
 50}
 51
 52/**
 53 * board_added - Called after a board has been added to the system.
 54 * @ctrl: PCIe hotplug controller where board is added
 55 *
 56 * Turns power on for the board.
 57 * Configures board.
 58 */
 59static int board_added(struct controller *ctrl)
 60{
 61	int retval = 0;
 62	struct pci_bus *parent = ctrl->pcie->port->subordinate;
 63
 64	if (POWER_CTRL(ctrl)) {
 65		/* Power on slot */
 66		retval = pciehp_power_on_slot(ctrl);
 67		if (retval)
 68			return retval;
 69	}
 70
 71	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK,
 72			      INDICATOR_NOOP);
 73
 74	/* Check link training status */
 75	retval = pciehp_check_link_status(ctrl);
 76	if (retval) {
 77		ctrl_err(ctrl, "Failed to check link status\n");
 78		goto err_exit;
 79	}
 80
 81	/* Check for a power fault */
 82	if (ctrl->power_fault_detected || pciehp_query_power_fault(ctrl)) {
 83		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
 84		retval = -EIO;
 85		goto err_exit;
 86	}
 87
 88	retval = pciehp_configure_device(ctrl);
 89	if (retval) {
 90		if (retval != -EEXIST) {
 91			ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
 92				 pci_domain_nr(parent), parent->number);
 93			goto err_exit;
 94		}
 95	}
 96
 97	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON,
 98			      PCI_EXP_SLTCTL_ATTN_IND_OFF);
 99	return 0;
100
101err_exit:
102	set_slot_off(ctrl);
103	return retval;
104}
105
106/**
107 * remove_board - Turn off slot and Power Indicator
108 * @ctrl: PCIe hotplug controller where board is being removed
109 * @safe_removal: whether the board is safely removed (versus surprise removed)
110 */
111static void remove_board(struct controller *ctrl, bool safe_removal)
112{
113	pciehp_unconfigure_device(ctrl, safe_removal);
114
115	if (POWER_CTRL(ctrl)) {
116		pciehp_power_off_slot(ctrl);
117
118		/*
119		 * After turning power off, we must wait for at least 1 second
120		 * before taking any action that relies on power having been
121		 * removed from the slot/adapter.
122		 */
123		msleep(1000);
124
125		/* Ignore link or presence changes caused by power off */
126		atomic_and(~(PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC),
127			   &ctrl->pending_events);
128	}
129
130	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
131			      INDICATOR_NOOP);
132}
133
134static int pciehp_enable_slot(struct controller *ctrl);
135static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal);
136
137void pciehp_request(struct controller *ctrl, int action)
138{
139	atomic_or(action, &ctrl->pending_events);
140	if (!pciehp_poll_mode)
141		irq_wake_thread(ctrl->pcie->irq, ctrl);
142}
143
144void pciehp_queue_pushbutton_work(struct work_struct *work)
145{
146	struct controller *ctrl = container_of(work, struct controller,
147					       button_work.work);
148
149	mutex_lock(&ctrl->state_lock);
150	switch (ctrl->state) {
151	case BLINKINGOFF_STATE:
152		pciehp_request(ctrl, DISABLE_SLOT);
153		break;
154	case BLINKINGON_STATE:
155		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
156		break;
157	default:
158		break;
159	}
160	mutex_unlock(&ctrl->state_lock);
161}
162
163void pciehp_handle_button_press(struct controller *ctrl)
164{
165	mutex_lock(&ctrl->state_lock);
166	switch (ctrl->state) {
167	case OFF_STATE:
168	case ON_STATE:
169		if (ctrl->state == ON_STATE) {
170			ctrl->state = BLINKINGOFF_STATE;
171			ctrl_info(ctrl, "Slot(%s): Powering off due to button press\n",
172				  slot_name(ctrl));
173		} else {
174			ctrl->state = BLINKINGON_STATE;
175			ctrl_info(ctrl, "Slot(%s) Powering on due to button press\n",
176				  slot_name(ctrl));
177		}
178		/* blink power indicator and turn off attention */
179		pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK,
180				      PCI_EXP_SLTCTL_ATTN_IND_OFF);
181		schedule_delayed_work(&ctrl->button_work, 5 * HZ);
182		break;
183	case BLINKINGOFF_STATE:
184	case BLINKINGON_STATE:
185		/*
186		 * Cancel if we are still blinking; this means that we
187		 * press the attention again before the 5 sec. limit
188		 * expires to cancel hot-add or hot-remove
189		 */
190		ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(ctrl));
191		cancel_delayed_work(&ctrl->button_work);
192		if (ctrl->state == BLINKINGOFF_STATE) {
193			ctrl->state = ON_STATE;
194			pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON,
195					      PCI_EXP_SLTCTL_ATTN_IND_OFF);
196		} else {
197			ctrl->state = OFF_STATE;
198			pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
199					      PCI_EXP_SLTCTL_ATTN_IND_OFF);
200		}
201		ctrl_info(ctrl, "Slot(%s): Action canceled due to button press\n",
202			  slot_name(ctrl));
203		break;
204	default:
205		ctrl_err(ctrl, "Slot(%s): Ignoring invalid state %#x\n",
206			 slot_name(ctrl), ctrl->state);
207		break;
208	}
209	mutex_unlock(&ctrl->state_lock);
210}
211
212void pciehp_handle_disable_request(struct controller *ctrl)
213{
214	mutex_lock(&ctrl->state_lock);
215	switch (ctrl->state) {
216	case BLINKINGON_STATE:
217	case BLINKINGOFF_STATE:
218		cancel_delayed_work(&ctrl->button_work);
219		break;
220	}
221	ctrl->state = POWEROFF_STATE;
222	mutex_unlock(&ctrl->state_lock);
223
224	ctrl->request_result = pciehp_disable_slot(ctrl, SAFE_REMOVAL);
225}
226
227void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
228{
229	bool present, link_active;
230
231	/*
232	 * If the slot is on and presence or link has changed, turn it off.
233	 * Even if it's occupied again, we cannot assume the card is the same.
234	 */
235	mutex_lock(&ctrl->state_lock);
236	switch (ctrl->state) {
237	case BLINKINGOFF_STATE:
238		cancel_delayed_work(&ctrl->button_work);
239		/* fall through */
240	case ON_STATE:
241		ctrl->state = POWEROFF_STATE;
242		mutex_unlock(&ctrl->state_lock);
243		if (events & PCI_EXP_SLTSTA_DLLSC)
244			ctrl_info(ctrl, "Slot(%s): Link Down\n",
245				  slot_name(ctrl));
246		if (events & PCI_EXP_SLTSTA_PDC)
247			ctrl_info(ctrl, "Slot(%s): Card not present\n",
248				  slot_name(ctrl));
249		pciehp_disable_slot(ctrl, SURPRISE_REMOVAL);
250		break;
251	default:
252		mutex_unlock(&ctrl->state_lock);
253		break;
254	}
255
256	/* Turn the slot on if it's occupied or link is up */
257	mutex_lock(&ctrl->state_lock);
258	present = pciehp_card_present(ctrl);
259	link_active = pciehp_check_link_active(ctrl);
260	if (!present && !link_active) {
261		mutex_unlock(&ctrl->state_lock);
262		return;
263	}
264
265	switch (ctrl->state) {
266	case BLINKINGON_STATE:
267		cancel_delayed_work(&ctrl->button_work);
268		/* fall through */
269	case OFF_STATE:
270		ctrl->state = POWERON_STATE;
271		mutex_unlock(&ctrl->state_lock);
272		if (present)
273			ctrl_info(ctrl, "Slot(%s): Card present\n",
274				  slot_name(ctrl));
275		if (link_active)
276			ctrl_info(ctrl, "Slot(%s): Link Up\n",
277				  slot_name(ctrl));
278		ctrl->request_result = pciehp_enable_slot(ctrl);
279		break;
280	default:
281		mutex_unlock(&ctrl->state_lock);
282		break;
283	}
284}
285
286static int __pciehp_enable_slot(struct controller *ctrl)
287{
288	u8 getstatus = 0;
289
290	if (MRL_SENS(ctrl)) {
291		pciehp_get_latch_status(ctrl, &getstatus);
292		if (getstatus) {
293			ctrl_info(ctrl, "Slot(%s): Latch open\n",
294				  slot_name(ctrl));
295			return -ENODEV;
296		}
297	}
298
299	if (POWER_CTRL(ctrl)) {
300		pciehp_get_power_status(ctrl, &getstatus);
301		if (getstatus) {
302			ctrl_info(ctrl, "Slot(%s): Already enabled\n",
303				  slot_name(ctrl));
304			return 0;
305		}
306	}
307
308	return board_added(ctrl);
309}
310
311static int pciehp_enable_slot(struct controller *ctrl)
312{
313	int ret;
314
315	pm_runtime_get_sync(&ctrl->pcie->port->dev);
316	ret = __pciehp_enable_slot(ctrl);
317	if (ret && ATTN_BUTTN(ctrl))
318		/* may be blinking */
319		pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
320				      INDICATOR_NOOP);
321	pm_runtime_put(&ctrl->pcie->port->dev);
322
323	mutex_lock(&ctrl->state_lock);
324	ctrl->state = ret ? OFF_STATE : ON_STATE;
325	mutex_unlock(&ctrl->state_lock);
326
327	return ret;
328}
329
330static int __pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
331{
332	u8 getstatus = 0;
333
334	if (POWER_CTRL(ctrl)) {
335		pciehp_get_power_status(ctrl, &getstatus);
336		if (!getstatus) {
337			ctrl_info(ctrl, "Slot(%s): Already disabled\n",
338				  slot_name(ctrl));
339			return -EINVAL;
340		}
341	}
342
343	remove_board(ctrl, safe_removal);
344	return 0;
345}
346
347static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
348{
349	int ret;
350
351	pm_runtime_get_sync(&ctrl->pcie->port->dev);
352	ret = __pciehp_disable_slot(ctrl, safe_removal);
353	pm_runtime_put(&ctrl->pcie->port->dev);
354
355	mutex_lock(&ctrl->state_lock);
356	ctrl->state = OFF_STATE;
357	mutex_unlock(&ctrl->state_lock);
358
359	return ret;
360}
361
362int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
363{
364	struct controller *ctrl = to_ctrl(hotplug_slot);
365
366	mutex_lock(&ctrl->state_lock);
367	switch (ctrl->state) {
368	case BLINKINGON_STATE:
369	case OFF_STATE:
370		mutex_unlock(&ctrl->state_lock);
371		/*
372		 * The IRQ thread becomes a no-op if the user pulls out the
373		 * card before the thread wakes up, so initialize to -ENODEV.
374		 */
375		ctrl->request_result = -ENODEV;
376		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
377		wait_event(ctrl->requester,
378			   !atomic_read(&ctrl->pending_events));
 
379		return ctrl->request_result;
380	case POWERON_STATE:
381		ctrl_info(ctrl, "Slot(%s): Already in powering on state\n",
382			  slot_name(ctrl));
383		break;
384	case BLINKINGOFF_STATE:
385	case ON_STATE:
386	case POWEROFF_STATE:
387		ctrl_info(ctrl, "Slot(%s): Already enabled\n",
388			  slot_name(ctrl));
389		break;
390	default:
391		ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
392			 slot_name(ctrl), ctrl->state);
393		break;
394	}
395	mutex_unlock(&ctrl->state_lock);
396
397	return -ENODEV;
398}
399
400int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
401{
402	struct controller *ctrl = to_ctrl(hotplug_slot);
403
404	mutex_lock(&ctrl->state_lock);
405	switch (ctrl->state) {
406	case BLINKINGOFF_STATE:
407	case ON_STATE:
408		mutex_unlock(&ctrl->state_lock);
409		pciehp_request(ctrl, DISABLE_SLOT);
410		wait_event(ctrl->requester,
411			   !atomic_read(&ctrl->pending_events));
 
412		return ctrl->request_result;
413	case POWEROFF_STATE:
414		ctrl_info(ctrl, "Slot(%s): Already in powering off state\n",
415			  slot_name(ctrl));
416		break;
417	case BLINKINGON_STATE:
418	case OFF_STATE:
419	case POWERON_STATE:
420		ctrl_info(ctrl, "Slot(%s): Already disabled\n",
421			  slot_name(ctrl));
422		break;
423	default:
424		ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
425			 slot_name(ctrl), ctrl->state);
426		break;
427	}
428	mutex_unlock(&ctrl->state_lock);
429
430	return -ENODEV;
431}
v5.14.15
  1// SPDX-License-Identifier: GPL-2.0+
  2/*
  3 * PCI Express Hot Plug Controller Driver
  4 *
  5 * Copyright (C) 1995,2001 Compaq Computer Corporation
  6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
  7 * Copyright (C) 2001 IBM Corp.
  8 * Copyright (C) 2003-2004 Intel Corporation
  9 *
 10 * All rights reserved.
 11 *
 12 * Send feedback to <greg@kroah.com>, <kristen.c.accardi@intel.com>
 13 *
 14 */
 15
 16#define dev_fmt(fmt) "pciehp: " fmt
 17
 18#include <linux/kernel.h>
 19#include <linux/types.h>
 20#include <linux/pm_runtime.h>
 21#include <linux/pci.h>
 22#include "pciehp.h"
 23
 24/* The following routines constitute the bulk of the
 25   hotplug controller logic
 26 */
 27
 28#define SAFE_REMOVAL	 true
 29#define SURPRISE_REMOVAL false
 30
 31static void set_slot_off(struct controller *ctrl)
 32{
 33	/*
 34	 * Turn off slot, turn on attention indicator, turn off power
 35	 * indicator
 36	 */
 37	if (POWER_CTRL(ctrl)) {
 38		pciehp_power_off_slot(ctrl);
 39
 40		/*
 41		 * After turning power off, we must wait for at least 1 second
 42		 * before taking any action that relies on power having been
 43		 * removed from the slot/adapter.
 44		 */
 45		msleep(1000);
 46	}
 47
 48	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
 49			      PCI_EXP_SLTCTL_ATTN_IND_ON);
 50}
 51
 52/**
 53 * board_added - Called after a board has been added to the system.
 54 * @ctrl: PCIe hotplug controller where board is added
 55 *
 56 * Turns power on for the board.
 57 * Configures board.
 58 */
 59static int board_added(struct controller *ctrl)
 60{
 61	int retval = 0;
 62	struct pci_bus *parent = ctrl->pcie->port->subordinate;
 63
 64	if (POWER_CTRL(ctrl)) {
 65		/* Power on slot */
 66		retval = pciehp_power_on_slot(ctrl);
 67		if (retval)
 68			return retval;
 69	}
 70
 71	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK,
 72			      INDICATOR_NOOP);
 73
 74	/* Check link training status */
 75	retval = pciehp_check_link_status(ctrl);
 76	if (retval)
 
 77		goto err_exit;
 
 78
 79	/* Check for a power fault */
 80	if (ctrl->power_fault_detected || pciehp_query_power_fault(ctrl)) {
 81		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
 82		retval = -EIO;
 83		goto err_exit;
 84	}
 85
 86	retval = pciehp_configure_device(ctrl);
 87	if (retval) {
 88		if (retval != -EEXIST) {
 89			ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
 90				 pci_domain_nr(parent), parent->number);
 91			goto err_exit;
 92		}
 93	}
 94
 95	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON,
 96			      PCI_EXP_SLTCTL_ATTN_IND_OFF);
 97	return 0;
 98
 99err_exit:
100	set_slot_off(ctrl);
101	return retval;
102}
103
104/**
105 * remove_board - Turn off slot and Power Indicator
106 * @ctrl: PCIe hotplug controller where board is being removed
107 * @safe_removal: whether the board is safely removed (versus surprise removed)
108 */
109static void remove_board(struct controller *ctrl, bool safe_removal)
110{
111	pciehp_unconfigure_device(ctrl, safe_removal);
112
113	if (POWER_CTRL(ctrl)) {
114		pciehp_power_off_slot(ctrl);
115
116		/*
117		 * After turning power off, we must wait for at least 1 second
118		 * before taking any action that relies on power having been
119		 * removed from the slot/adapter.
120		 */
121		msleep(1000);
122
123		/* Ignore link or presence changes caused by power off */
124		atomic_and(~(PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC),
125			   &ctrl->pending_events);
126	}
127
128	pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
129			      INDICATOR_NOOP);
130}
131
132static int pciehp_enable_slot(struct controller *ctrl);
133static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal);
134
135void pciehp_request(struct controller *ctrl, int action)
136{
137	atomic_or(action, &ctrl->pending_events);
138	if (!pciehp_poll_mode)
139		irq_wake_thread(ctrl->pcie->irq, ctrl);
140}
141
142void pciehp_queue_pushbutton_work(struct work_struct *work)
143{
144	struct controller *ctrl = container_of(work, struct controller,
145					       button_work.work);
146
147	mutex_lock(&ctrl->state_lock);
148	switch (ctrl->state) {
149	case BLINKINGOFF_STATE:
150		pciehp_request(ctrl, DISABLE_SLOT);
151		break;
152	case BLINKINGON_STATE:
153		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
154		break;
155	default:
156		break;
157	}
158	mutex_unlock(&ctrl->state_lock);
159}
160
161void pciehp_handle_button_press(struct controller *ctrl)
162{
163	mutex_lock(&ctrl->state_lock);
164	switch (ctrl->state) {
165	case OFF_STATE:
166	case ON_STATE:
167		if (ctrl->state == ON_STATE) {
168			ctrl->state = BLINKINGOFF_STATE;
169			ctrl_info(ctrl, "Slot(%s): Powering off due to button press\n",
170				  slot_name(ctrl));
171		} else {
172			ctrl->state = BLINKINGON_STATE;
173			ctrl_info(ctrl, "Slot(%s) Powering on due to button press\n",
174				  slot_name(ctrl));
175		}
176		/* blink power indicator and turn off attention */
177		pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK,
178				      PCI_EXP_SLTCTL_ATTN_IND_OFF);
179		schedule_delayed_work(&ctrl->button_work, 5 * HZ);
180		break;
181	case BLINKINGOFF_STATE:
182	case BLINKINGON_STATE:
183		/*
184		 * Cancel if we are still blinking; this means that we
185		 * press the attention again before the 5 sec. limit
186		 * expires to cancel hot-add or hot-remove
187		 */
188		ctrl_info(ctrl, "Slot(%s): Button cancel\n", slot_name(ctrl));
189		cancel_delayed_work(&ctrl->button_work);
190		if (ctrl->state == BLINKINGOFF_STATE) {
191			ctrl->state = ON_STATE;
192			pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON,
193					      PCI_EXP_SLTCTL_ATTN_IND_OFF);
194		} else {
195			ctrl->state = OFF_STATE;
196			pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
197					      PCI_EXP_SLTCTL_ATTN_IND_OFF);
198		}
199		ctrl_info(ctrl, "Slot(%s): Action canceled due to button press\n",
200			  slot_name(ctrl));
201		break;
202	default:
203		ctrl_err(ctrl, "Slot(%s): Ignoring invalid state %#x\n",
204			 slot_name(ctrl), ctrl->state);
205		break;
206	}
207	mutex_unlock(&ctrl->state_lock);
208}
209
210void pciehp_handle_disable_request(struct controller *ctrl)
211{
212	mutex_lock(&ctrl->state_lock);
213	switch (ctrl->state) {
214	case BLINKINGON_STATE:
215	case BLINKINGOFF_STATE:
216		cancel_delayed_work(&ctrl->button_work);
217		break;
218	}
219	ctrl->state = POWEROFF_STATE;
220	mutex_unlock(&ctrl->state_lock);
221
222	ctrl->request_result = pciehp_disable_slot(ctrl, SAFE_REMOVAL);
223}
224
225void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)
226{
227	int present, link_active;
228
229	/*
230	 * If the slot is on and presence or link has changed, turn it off.
231	 * Even if it's occupied again, we cannot assume the card is the same.
232	 */
233	mutex_lock(&ctrl->state_lock);
234	switch (ctrl->state) {
235	case BLINKINGOFF_STATE:
236		cancel_delayed_work(&ctrl->button_work);
237		fallthrough;
238	case ON_STATE:
239		ctrl->state = POWEROFF_STATE;
240		mutex_unlock(&ctrl->state_lock);
241		if (events & PCI_EXP_SLTSTA_DLLSC)
242			ctrl_info(ctrl, "Slot(%s): Link Down\n",
243				  slot_name(ctrl));
244		if (events & PCI_EXP_SLTSTA_PDC)
245			ctrl_info(ctrl, "Slot(%s): Card not present\n",
246				  slot_name(ctrl));
247		pciehp_disable_slot(ctrl, SURPRISE_REMOVAL);
248		break;
249	default:
250		mutex_unlock(&ctrl->state_lock);
251		break;
252	}
253
254	/* Turn the slot on if it's occupied or link is up */
255	mutex_lock(&ctrl->state_lock);
256	present = pciehp_card_present(ctrl);
257	link_active = pciehp_check_link_active(ctrl);
258	if (present <= 0 && link_active <= 0) {
259		mutex_unlock(&ctrl->state_lock);
260		return;
261	}
262
263	switch (ctrl->state) {
264	case BLINKINGON_STATE:
265		cancel_delayed_work(&ctrl->button_work);
266		fallthrough;
267	case OFF_STATE:
268		ctrl->state = POWERON_STATE;
269		mutex_unlock(&ctrl->state_lock);
270		if (present)
271			ctrl_info(ctrl, "Slot(%s): Card present\n",
272				  slot_name(ctrl));
273		if (link_active)
274			ctrl_info(ctrl, "Slot(%s): Link Up\n",
275				  slot_name(ctrl));
276		ctrl->request_result = pciehp_enable_slot(ctrl);
277		break;
278	default:
279		mutex_unlock(&ctrl->state_lock);
280		break;
281	}
282}
283
284static int __pciehp_enable_slot(struct controller *ctrl)
285{
286	u8 getstatus = 0;
287
288	if (MRL_SENS(ctrl)) {
289		pciehp_get_latch_status(ctrl, &getstatus);
290		if (getstatus) {
291			ctrl_info(ctrl, "Slot(%s): Latch open\n",
292				  slot_name(ctrl));
293			return -ENODEV;
294		}
295	}
296
297	if (POWER_CTRL(ctrl)) {
298		pciehp_get_power_status(ctrl, &getstatus);
299		if (getstatus) {
300			ctrl_info(ctrl, "Slot(%s): Already enabled\n",
301				  slot_name(ctrl));
302			return 0;
303		}
304	}
305
306	return board_added(ctrl);
307}
308
309static int pciehp_enable_slot(struct controller *ctrl)
310{
311	int ret;
312
313	pm_runtime_get_sync(&ctrl->pcie->port->dev);
314	ret = __pciehp_enable_slot(ctrl);
315	if (ret && ATTN_BUTTN(ctrl))
316		/* may be blinking */
317		pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
318				      INDICATOR_NOOP);
319	pm_runtime_put(&ctrl->pcie->port->dev);
320
321	mutex_lock(&ctrl->state_lock);
322	ctrl->state = ret ? OFF_STATE : ON_STATE;
323	mutex_unlock(&ctrl->state_lock);
324
325	return ret;
326}
327
328static int __pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
329{
330	u8 getstatus = 0;
331
332	if (POWER_CTRL(ctrl)) {
333		pciehp_get_power_status(ctrl, &getstatus);
334		if (!getstatus) {
335			ctrl_info(ctrl, "Slot(%s): Already disabled\n",
336				  slot_name(ctrl));
337			return -EINVAL;
338		}
339	}
340
341	remove_board(ctrl, safe_removal);
342	return 0;
343}
344
345static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal)
346{
347	int ret;
348
349	pm_runtime_get_sync(&ctrl->pcie->port->dev);
350	ret = __pciehp_disable_slot(ctrl, safe_removal);
351	pm_runtime_put(&ctrl->pcie->port->dev);
352
353	mutex_lock(&ctrl->state_lock);
354	ctrl->state = OFF_STATE;
355	mutex_unlock(&ctrl->state_lock);
356
357	return ret;
358}
359
360int pciehp_sysfs_enable_slot(struct hotplug_slot *hotplug_slot)
361{
362	struct controller *ctrl = to_ctrl(hotplug_slot);
363
364	mutex_lock(&ctrl->state_lock);
365	switch (ctrl->state) {
366	case BLINKINGON_STATE:
367	case OFF_STATE:
368		mutex_unlock(&ctrl->state_lock);
369		/*
370		 * The IRQ thread becomes a no-op if the user pulls out the
371		 * card before the thread wakes up, so initialize to -ENODEV.
372		 */
373		ctrl->request_result = -ENODEV;
374		pciehp_request(ctrl, PCI_EXP_SLTSTA_PDC);
375		wait_event(ctrl->requester,
376			   !atomic_read(&ctrl->pending_events) &&
377			   !ctrl->ist_running);
378		return ctrl->request_result;
379	case POWERON_STATE:
380		ctrl_info(ctrl, "Slot(%s): Already in powering on state\n",
381			  slot_name(ctrl));
382		break;
383	case BLINKINGOFF_STATE:
384	case ON_STATE:
385	case POWEROFF_STATE:
386		ctrl_info(ctrl, "Slot(%s): Already enabled\n",
387			  slot_name(ctrl));
388		break;
389	default:
390		ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
391			 slot_name(ctrl), ctrl->state);
392		break;
393	}
394	mutex_unlock(&ctrl->state_lock);
395
396	return -ENODEV;
397}
398
399int pciehp_sysfs_disable_slot(struct hotplug_slot *hotplug_slot)
400{
401	struct controller *ctrl = to_ctrl(hotplug_slot);
402
403	mutex_lock(&ctrl->state_lock);
404	switch (ctrl->state) {
405	case BLINKINGOFF_STATE:
406	case ON_STATE:
407		mutex_unlock(&ctrl->state_lock);
408		pciehp_request(ctrl, DISABLE_SLOT);
409		wait_event(ctrl->requester,
410			   !atomic_read(&ctrl->pending_events) &&
411			   !ctrl->ist_running);
412		return ctrl->request_result;
413	case POWEROFF_STATE:
414		ctrl_info(ctrl, "Slot(%s): Already in powering off state\n",
415			  slot_name(ctrl));
416		break;
417	case BLINKINGON_STATE:
418	case OFF_STATE:
419	case POWERON_STATE:
420		ctrl_info(ctrl, "Slot(%s): Already disabled\n",
421			  slot_name(ctrl));
422		break;
423	default:
424		ctrl_err(ctrl, "Slot(%s): Invalid state %#x\n",
425			 slot_name(ctrl), ctrl->state);
426		break;
427	}
428	mutex_unlock(&ctrl->state_lock);
429
430	return -ENODEV;
431}