1 // SPDX-License-Identifier: GPL-2.0+
3  * PCI Express Hot Plug Controller Driver
6  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
8  * Copyright (C) 2003-2004 Intel Corporation
25    hotplug controller logic
31 static void set_slot_off(struct controller *ctrl)  in set_slot_off()
34 	 * Turn off slot, turn on attention indicator, turn off power  in set_slot_off()
41 		 * After turning power off, we must wait for at least 1 second  in set_slot_off()
42 		 * before taking any action that relies on power having been  in set_slot_off()
53  * board_added - Called after a board has been added to the system.
54  * @ctrl: PCIe hotplug controller where board is added
56  * Turns power on for the board.
59 static int board_added(struct controller *ctrl)  in board_added()
62 	struct pci_bus *parent = ctrl->pcie->port->subordinate;  in board_added()
65 		/* Power on slot */  in board_added()
79 	/* Check for a power fault */  in board_added()
80 	if (ctrl->power_fault_detected || pciehp_query_power_fault(ctrl)) {  in board_added()
81 		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));  in board_added()
82 		retval = -EIO;  in board_added()
88 		if (retval != -EEXIST) {  in board_added()
90 				 pci_domain_nr(parent), parent->number);  in board_added()
105  * remove_board - Turn off slot and Power Indicator
106  * @ctrl: PCIe hotplug controller where board is being removed
109 static void remove_board(struct controller *ctrl, bool safe_removal)  in remove_board()
117 		 * After turning power off, we must wait for at least 1 second  in remove_board()
118 		 * before taking any action that relies on power having been  in remove_board()
123 		/* Ignore link or presence changes caused by power off */  in remove_board()
125 			   &ctrl->pending_events);  in remove_board()
132 static int pciehp_enable_slot(struct controller *ctrl);
133 static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal);
135 void pciehp_request(struct controller *ctrl, int action)  in pciehp_request()
137 	atomic_or(action, &ctrl->pending_events);  in pciehp_request()
139 		irq_wake_thread(ctrl->pcie->irq, ctrl);  in pciehp_request()
144 	struct controller *ctrl = container_of(work, struct controller,  in pciehp_queue_pushbutton_work()
147 	mutex_lock(&ctrl->state_lock);  in pciehp_queue_pushbutton_work()
148 	switch (ctrl->state) {  in pciehp_queue_pushbutton_work()
158 	mutex_unlock(&ctrl->state_lock);  in pciehp_queue_pushbutton_work()
161 void pciehp_handle_button_press(struct controller *ctrl)  in pciehp_handle_button_press()
163 	mutex_lock(&ctrl->state_lock);  in pciehp_handle_button_press()
164 	switch (ctrl->state) {  in pciehp_handle_button_press()
167 		if (ctrl->state == ON_STATE) {  in pciehp_handle_button_press()
168 			ctrl->state = BLINKINGOFF_STATE;  in pciehp_handle_button_press()
172 			ctrl->state = BLINKINGON_STATE;  in pciehp_handle_button_press()
176 		/* blink power indicator and turn off attention */  in pciehp_handle_button_press()
179 		schedule_delayed_work(&ctrl->button_work, 5 * HZ);  in pciehp_handle_button_press()
186 		 * expires to cancel hot-add or hot-remove  in pciehp_handle_button_press()
189 		cancel_delayed_work(&ctrl->button_work);  in pciehp_handle_button_press()
190 		if (ctrl->state == BLINKINGOFF_STATE) {  in pciehp_handle_button_press()
191 			ctrl->state = ON_STATE;  in pciehp_handle_button_press()
195 			ctrl->state = OFF_STATE;  in pciehp_handle_button_press()
204 			 slot_name(ctrl), ctrl->state);  in pciehp_handle_button_press()
207 	mutex_unlock(&ctrl->state_lock);  in pciehp_handle_button_press()
210 void pciehp_handle_disable_request(struct controller *ctrl)  in pciehp_handle_disable_request()
212 	mutex_lock(&ctrl->state_lock);  in pciehp_handle_disable_request()
213 	switch (ctrl->state) {  in pciehp_handle_disable_request()
216 		cancel_delayed_work(&ctrl->button_work);  in pciehp_handle_disable_request()
219 	ctrl->state = POWEROFF_STATE;  in pciehp_handle_disable_request()
220 	mutex_unlock(&ctrl->state_lock);  in pciehp_handle_disable_request()
222 	ctrl->request_result = pciehp_disable_slot(ctrl, SAFE_REMOVAL);  in pciehp_handle_disable_request()
225 void pciehp_handle_presence_or_link_change(struct controller *ctrl, u32 events)  in pciehp_handle_presence_or_link_change()
233 	mutex_lock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
234 	switch (ctrl->state) {  in pciehp_handle_presence_or_link_change()
236 		cancel_delayed_work(&ctrl->button_work);  in pciehp_handle_presence_or_link_change()
239 		ctrl->state = POWEROFF_STATE;  in pciehp_handle_presence_or_link_change()
240 		mutex_unlock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
250 		mutex_unlock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
255 	mutex_lock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
259 		mutex_unlock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
263 	switch (ctrl->state) {  in pciehp_handle_presence_or_link_change()
265 		cancel_delayed_work(&ctrl->button_work);  in pciehp_handle_presence_or_link_change()
268 		ctrl->state = POWERON_STATE;  in pciehp_handle_presence_or_link_change()
269 		mutex_unlock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
276 		ctrl->request_result = pciehp_enable_slot(ctrl);  in pciehp_handle_presence_or_link_change()
279 		mutex_unlock(&ctrl->state_lock);  in pciehp_handle_presence_or_link_change()
284 static int __pciehp_enable_slot(struct controller *ctrl)  in __pciehp_enable_slot()
293 			return -ENODEV;  in __pciehp_enable_slot()
309 static int pciehp_enable_slot(struct controller *ctrl)  in pciehp_enable_slot()
313 	pm_runtime_get_sync(&ctrl->pcie->port->dev);  in pciehp_enable_slot()
319 	pm_runtime_put(&ctrl->pcie->port->dev);  in pciehp_enable_slot()
321 	mutex_lock(&ctrl->state_lock);  in pciehp_enable_slot()
322 	ctrl->state = ret ? OFF_STATE : ON_STATE;  in pciehp_enable_slot()
323 	mutex_unlock(&ctrl->state_lock);  in pciehp_enable_slot()
328 static int __pciehp_disable_slot(struct controller *ctrl, bool safe_removal)  in __pciehp_disable_slot()
337 			return -EINVAL;  in __pciehp_disable_slot()
345 static int pciehp_disable_slot(struct controller *ctrl, bool safe_removal)  in pciehp_disable_slot()
349 	pm_runtime_get_sync(&ctrl->pcie->port->dev);  in pciehp_disable_slot()
351 	pm_runtime_put(&ctrl->pcie->port->dev);  in pciehp_disable_slot()
353 	mutex_lock(&ctrl->state_lock);  in pciehp_disable_slot()
354 	ctrl->state = OFF_STATE;  in pciehp_disable_slot()
355 	mutex_unlock(&ctrl->state_lock);  in pciehp_disable_slot()
362 	struct controller *ctrl = to_ctrl(hotplug_slot);  in pciehp_sysfs_enable_slot()
364 	mutex_lock(&ctrl->state_lock);  in pciehp_sysfs_enable_slot()
365 	switch (ctrl->state) {  in pciehp_sysfs_enable_slot()
368 		mutex_unlock(&ctrl->state_lock);  in pciehp_sysfs_enable_slot()
370 		 * The IRQ thread becomes a no-op if the user pulls out the  in pciehp_sysfs_enable_slot()
371 		 * card before the thread wakes up, so initialize to -ENODEV.  in pciehp_sysfs_enable_slot()
373 		ctrl->request_result = -ENODEV;  in pciehp_sysfs_enable_slot()
375 		wait_event(ctrl->requester,  in pciehp_sysfs_enable_slot()
376 			   !atomic_read(&ctrl->pending_events) &&  in pciehp_sysfs_enable_slot()
377 			   !ctrl->ist_running);  in pciehp_sysfs_enable_slot()
378 		return ctrl->request_result;  in pciehp_sysfs_enable_slot()
391 			 slot_name(ctrl), ctrl->state);  in pciehp_sysfs_enable_slot()
394 	mutex_unlock(&ctrl->state_lock);  in pciehp_sysfs_enable_slot()
396 	return -ENODEV;  in pciehp_sysfs_enable_slot()
401 	struct controller *ctrl = to_ctrl(hotplug_slot);  in pciehp_sysfs_disable_slot()
403 	mutex_lock(&ctrl->state_lock);  in pciehp_sysfs_disable_slot()
404 	switch (ctrl->state) {  in pciehp_sysfs_disable_slot()
407 		mutex_unlock(&ctrl->state_lock);  in pciehp_sysfs_disable_slot()
409 		wait_event(ctrl->requester,  in pciehp_sysfs_disable_slot()
410 			   !atomic_read(&ctrl->pending_events) &&  in pciehp_sysfs_disable_slot()
411 			   !ctrl->ist_running);  in pciehp_sysfs_disable_slot()
412 		return ctrl->request_result;  in pciehp_sysfs_disable_slot()
425 			 slot_name(ctrl), ctrl->state);  in pciehp_sysfs_disable_slot()
428 	mutex_unlock(&ctrl->state_lock);  in pciehp_sysfs_disable_slot()
430 	return -ENODEV;  in pciehp_sysfs_disable_slot()