1 // SPDX-License-Identifier: GPL-2.0
3  * PCIe Enclosure management driver created for LED interfaces based on
5  * they blink - it is hardware defined.
13  * _DSM Definitions for PCIe SSD Status LED
16  * Two backends are supported to manipulate indications: Direct NPEM register
20  * Copyright (c) 2021-2022 Dell Inc.
21  * Copyright (c) 2023-2024 Intel Corporation
39 	u32 bit;  member
65 /* _DSM PCIe SSD LED States correspond to NPEM register values */
81 	for (ind = inds; ind->bit; ind++)
85  * should not touch bits that are not defined and for which LED devices are
99 		supported_indications |= ind->bit;  in reg_to_indications()
105  * struct npem_led - LED details
108  * @name: LED name
109  * @led: LED device
115 	struct led_classdev led;  member
119  * struct npem_ops - backend specific callbacks
125  *	inds: bit mask to set
137  * struct npem - NPEM device properties
140  * @lock: serializes concurrent access to NPEM device by multiple LED devices
141  * @pos: cached offset of NPEM Capability Register in Configuration Space;
143  * @supported_indications: cached bit mask of supported indications;
144  *	non-indication and reserved bits in the NPEM Capability Register are
145  *	cleared in this bit mask
146  * @active_indications: cached bit mask of active indications;
147  *	non-indication and reserved bits in the NPEM Control Register are
148  *	cleared in this bit mask
153  *	(on first access to an LED), IPMI drivers are given a chance to load.
154  *	If they are not loaded in time, users will see various errors on LED
155  *	access in dmesg. Once they are loaded, the errors go away and LED
158  * @leds: array containing LED class devices of all supported LEDs
174 	int ret = pci_read_config_dword(npem->dev, npem->pos + reg, val);  in npem_read_reg()
181 	int pos = npem->pos + PCI_NPEM_CTRL;  in npem_write_ctrl()
182 	int ret = pci_write_config_dword(npem->dev, pos, reg);  in npem_write_ctrl()
202 	*inds = ctrl & npem->supported_indications;  in npem_get_active_indications()
212 	lockdep_assert_held(&npem->lock);  in npem_set_active_indications()
214 	/* This bit is always required */  in npem_set_active_indications()
224 	 * the status register, but rather poll under interrupt at a reduced  in npem_set_active_indications()
240 	 * All writes to control register, including writes that do not change  in npem_set_active_indications()
241 	 * the register value, are NPEM commands and should eventually result  in npem_set_active_indications()
242 	 * in a command completion indication in the NPEM Status Register.  in npem_set_active_indications()
246 	 * Register may not be updated, or other conflicting bits may be  in npem_set_active_indications()
247 	 * cleared. Spec is not strict here. Read NPEM Control register after  in npem_set_active_indications()
248 	 * write to keep cache in-sync.  in npem_set_active_indications()
250 	return npem_get_active_indications(npem, &npem->active_indications);  in npem_set_active_indications()
272 	handle = ACPI_HANDLE(&pdev->dev);  in npem_has_dsm()
277 			      BIT(GET_SUPPORTED_STATES_DSM) |  in npem_has_dsm()
278 			      BIT(GET_STATE_DSM) | BIT(SET_STATE_DSM));  in npem_has_dsm()
289  * dsm_evaluate() - send DSM PCIe SSD Status LED command
291  * @dsm_func: DSM LED Function
301 	acpi_handle handle = ACPI_HANDLE(&pdev->dev);  in dsm_evaluate()
320 		return -EIO;  in dsm_evaluate()
322 	if (out_obj->buffer.length < sizeof(struct dsm_output)) {  in dsm_evaluate()
324 		return -EIO;  in dsm_evaluate()
327 	memcpy(output, out_obj->buffer.pointer, sizeof(struct dsm_output));  in dsm_evaluate()
342 		return -EIO;  in dsm_get()
350 	int ret = dsm_get(npem->dev, GET_STATE_DSM, buf);  in dsm_get_active_indications()
353 	*buf &= npem->supported_indications;  in dsm_get_active_indications()
360 	int ret = dsm_evaluate(npem->dev, SET_STATE_DSM, &output, value);  in dsm_set_active_indications()
368 		 * Not all bits are set. If this bit is set, the platform  in dsm_set_active_indications()
370 		 * should check the resulting PCIe SSD Status LED States to see  in dsm_set_active_indications()
373 		 * PCI Firmware Specification, r3.3 Table 4-19.  in dsm_set_active_indications()
376 			return -EIO;  in dsm_set_active_indications()
381 		return -EIO;  in dsm_set_active_indications()
384 	npem->active_indications = output.state;  in dsm_set_active_indications()
392 	.name = "_DSM PCIe SSD Status LED Management",
400 	lockdep_assert_held(&npem->lock);  in npem_initialize_active_indications()
402 	if (npem->active_inds_initialized)  in npem_initialize_active_indications()
405 	ret = npem->ops->get_active_indications(npem,  in npem_initialize_active_indications()
406 						&npem->active_indications);  in npem_initialize_active_indications()
410 	npem->active_inds_initialized = true;  in npem_initialize_active_indications()
419 static enum led_brightness brightness_get(struct led_classdev *led)  in brightness_get()  argument
421 	struct npem_led *nled = container_of(led, struct npem_led, led);  in brightness_get()
422 	struct npem *npem = nled->npem;  in brightness_get()
425 	ret = mutex_lock_interruptible(&npem->lock);  in brightness_get()
433 	if (npem->active_indications & nled->indication->bit)  in brightness_get()
437 	mutex_unlock(&npem->lock);  in brightness_get()
441 static int brightness_set(struct led_classdev *led,  in brightness_set()  argument
444 	struct npem_led *nled = container_of(led, struct npem_led, led);  in brightness_set()
445 	struct npem *npem = nled->npem;  in brightness_set()
449 	ret = mutex_lock_interruptible(&npem->lock);  in brightness_set()
458 		indications = npem->active_indications & ~(nled->indication->bit);  in brightness_set()
460 		indications = npem->active_indications | nled->indication->bit;  in brightness_set()
462 	ret = npem->ops->set_active_indications(npem, indications);  in brightness_set()
465 	mutex_unlock(&npem->lock);  in brightness_set()
477 	for (cnt = 0; cnt < npem->led_cnt; cnt++) {  in npem_free()
478 		nled = &npem->leds[cnt];  in npem_free()
480 		if (nled->name[0])  in npem_free()
481 			led_classdev_unregister(&nled->led);  in npem_free()
484 	mutex_destroy(&npem->lock);  in npem_free()
490 	struct led_classdev *led = &nled->led;  in pci_npem_set_led_classdev()  local
492 	char *name = nled->name;  in pci_npem_set_led_classdev()
495 	init_data.devicename = pci_name(npem->dev);  in pci_npem_set_led_classdev()
496 	init_data.default_label = nled->indication->name;  in pci_npem_set_led_classdev()
498 	ret = led_compose_name(&npem->dev->dev, &init_data, name);  in pci_npem_set_led_classdev()
502 	led->name = name;  in pci_npem_set_led_classdev()
503 	led->brightness_set_blocking = brightness_set;  in pci_npem_set_led_classdev()
504 	led->brightness_get = brightness_get;  in pci_npem_set_led_classdev()
505 	led->max_brightness = 1;  in pci_npem_set_led_classdev()
506 	led->default_trigger = "none";  in pci_npem_set_led_classdev()
507 	led->flags = 0;  in pci_npem_set_led_classdev()
509 	ret = led_classdev_register(&npem->dev->dev, led);  in pci_npem_set_led_classdev()
519 	u32 supported = reg_to_indications(caps, ops->inds);  in pci_npem_init()
529 		return -ENOMEM;  in pci_npem_init()
531 	npem->supported_indications = supported;  in pci_npem_init()
532 	npem->led_cnt = supported_cnt;  in pci_npem_init()
533 	npem->pos = pos;  in pci_npem_init()
534 	npem->dev = dev;  in pci_npem_init()
535 	npem->ops = ops;  in pci_npem_init()
537 	mutex_init(&npem->lock);  in pci_npem_init()
540 		if (!(npem->supported_indications & indication->bit))  in pci_npem_init()
543 		nled = &npem->leds[led_idx++];  in pci_npem_init()
544 		nled->indication = indication;  in pci_npem_init()
545 		nled->npem = npem;  in pci_npem_init()
554 	dev->npem = npem;  in pci_npem_init()
560 	npem_free(dev->npem);  in pci_npem_remove()
571 		 * OS should use the DSM for LED control if it is available  in pci_npem_create()
589 	pci_info(dev, "Configuring %s\n", ops->name);  in pci_npem_create()
593 		pci_err(dev, "Failed to register %s, err: %d\n", ops->name,  in pci_npem_create()