[mirror_ubuntu-artful-kernel.git] / drivers / acpi / irq.c

/*
 * ACPI GSI IRQ layer
 *
 * Copyright (C) 2015 ARM Ltd.
 * Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */
#include <linux/acpi.h>
#include <linux/irq.h>
#include <linux/irqdomain.h>
#include <linux/of.h>

enum acpi_irq_model_id acpi_irq_model;

static struct fwnode_handle *acpi_gsi_domain_id;

/**
 * acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI
 * @gsi: GSI IRQ number to map
 * @irq: pointer where linux IRQ number is stored
 *
 * irq location updated with irq value [>0 on success, 0 on failure]
 *
 * Returns: 0 on success
 *          -EINVAL on failure
 */
int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
{
	struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id,
							DOMAIN_BUS_ANY);

	*irq = irq_find_mapping(d, gsi);
	/*
	 * *irq == 0 means no mapping, that should
	 * be reported as a failure
	 */
	return (*irq > 0) ? 0 : -EINVAL;
}
EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);

/**
 * acpi_register_gsi() - Map a GSI to a linux IRQ number
 * @dev: device for which IRQ has to be mapped
 * @gsi: GSI IRQ number
 * @trigger: trigger type of the GSI number to be mapped
 * @polarity: polarity of the GSI to be mapped
 *
 * Returns: a valid linux IRQ number on success
 *          -EINVAL on failure
 */
int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
		      int polarity)
{
	struct irq_fwspec fwspec;

	if (WARN_ON(!acpi_gsi_domain_id)) {
		pr_warn("GSI: No registered irqchip, giving up\n");
		return -EINVAL;
	}

	fwspec.fwnode = acpi_gsi_domain_id;
	fwspec.param[0] = gsi;
	fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity);
	fwspec.param_count = 2;

	return irq_create_fwspec_mapping(&fwspec);
}
EXPORT_SYMBOL_GPL(acpi_register_gsi);

/**
 * acpi_unregister_gsi() - Free a GSI<->linux IRQ number mapping
 * @gsi: GSI IRQ number
 */
void acpi_unregister_gsi(u32 gsi)
{
	struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id,
							DOMAIN_BUS_ANY);
	int irq = irq_find_mapping(d, gsi);

	irq_dispose_mapping(irq);
}
EXPORT_SYMBOL_GPL(acpi_unregister_gsi);

/**
 * acpi_get_irq_source_fwhandle() - Retrieve fwhandle from IRQ resource source.
 * @source: acpi_resource_source to use for the lookup.
 *
 * Description:
 * Retrieve the fwhandle of the device referenced by the given IRQ resource
 * source.
 *
 * Return:
 * The referenced device fwhandle or NULL on failure
 */
static struct fwnode_handle *
acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source)
{
	struct fwnode_handle *result;
	struct acpi_device *device;
	acpi_handle handle;
	acpi_status status;

	if (!source->string_length)
		return acpi_gsi_domain_id;

	status = acpi_get_handle(NULL, source->string_ptr, &handle);
	if (WARN_ON(ACPI_FAILURE(status)))
		return NULL;

	device = acpi_bus_get_acpi_device(handle);
	if (WARN_ON(!device))
		return NULL;

	result = &device->fwnode;
	acpi_bus_put_acpi_device(device);
	return result;
}

/*
 * Context for the resource walk used to lookup IRQ resources.
 * Contains a return code, the lookup index, and references to the flags
 * and fwspec where the result is returned.
 */
struct acpi_irq_parse_one_ctx {
	int rc;
	unsigned int index;
	unsigned long *res_flags;
	struct irq_fwspec *fwspec;
};

/**
 * acpi_irq_parse_one_match - Handle a matching IRQ resource.
 * @fwnode: matching fwnode
 * @hwirq: hardware IRQ number
 * @triggering: triggering attributes of hwirq
 * @polarity: polarity attributes of hwirq
 * @polarity: polarity attributes of hwirq
 * @shareable: shareable attributes of hwirq
 * @ctx: acpi_irq_parse_one_ctx updated by this function
 *
 * Description:
 * Handle a matching IRQ resource by populating the given ctx with
 * the information passed.
 */
static inline void acpi_irq_parse_one_match(struct fwnode_handle *fwnode,
					    u32 hwirq, u8 triggering,
					    u8 polarity, u8 shareable,
					    struct acpi_irq_parse_one_ctx *ctx)
{
	if (!fwnode)
		return;
	ctx->rc = 0;
	*ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable);
	ctx->fwspec->fwnode = fwnode;
	ctx->fwspec->param[0] = hwirq;
	ctx->fwspec->param[1] = acpi_dev_get_irq_type(triggering, polarity);
	ctx->fwspec->param_count = 2;
}

/**
 * acpi_irq_parse_one_cb - Handle the given resource.
 * @ares: resource to handle
 * @context: context for the walk
 *
 * Description:
 * This is called by acpi_walk_resources passing each resource returned by
 * the _CRS method. We only inspect IRQ resources. Since IRQ resources
 * might contain multiple interrupts we check if the index is within this
 * one's interrupt array, otherwise we subtract the current resource IRQ
 * count from the lookup index to prepare for the next resource.
 * Once a match is found we call acpi_irq_parse_one_match to populate
 * the result and end the walk by returning AE_CTRL_TERMINATE.
 *
 * Return:
 * AE_OK if the walk should continue, AE_CTRL_TERMINATE if a matching
 * IRQ resource was found.
 */
static acpi_status acpi_irq_parse_one_cb(struct acpi_resource *ares,
					 void *context)
{
	struct acpi_irq_parse_one_ctx *ctx = context;
	struct acpi_resource_irq *irq;
	struct acpi_resource_extended_irq *eirq;
	struct fwnode_handle *fwnode;

	switch (ares->type) {
	case ACPI_RESOURCE_TYPE_IRQ:
		irq = &ares->data.irq;
		if (ctx->index >= irq->interrupt_count) {
			ctx->index -= irq->interrupt_count;
			return AE_OK;
		}
		fwnode = acpi_gsi_domain_id;
		acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index],
					 irq->triggering, irq->polarity,
					 irq->sharable, ctx);
		return AE_CTRL_TERMINATE;
	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
		eirq = &ares->data.extended_irq;
		if (eirq->producer_consumer == ACPI_PRODUCER)
			return AE_OK;
		if (ctx->index >= eirq->interrupt_count) {
			ctx->index -= eirq->interrupt_count;
			return AE_OK;
		}
		fwnode = acpi_get_irq_source_fwhandle(&eirq->resource_source);
		acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index],
					 eirq->triggering, eirq->polarity,
					 eirq->sharable, ctx);
		return AE_CTRL_TERMINATE;
	}

	return AE_OK;
}

/**
 * acpi_irq_parse_one - Resolve an interrupt for a device
 * @handle: the device whose interrupt is to be resolved
 * @index: index of the interrupt to resolve
 * @fwspec: structure irq_fwspec filled by this function
 * @flags: resource flags filled by this function
 *
 * Description:
 * Resolves an interrupt for a device by walking its CRS resources to find
 * the appropriate ACPI IRQ resource and populating the given struct irq_fwspec
 * and flags.
 *
 * Return:
 * The result stored in ctx.rc by the callback, or the default -EINVAL value
 * if an error occurs.
 */
static int acpi_irq_parse_one(acpi_handle handle, unsigned int index,
			      struct irq_fwspec *fwspec, unsigned long *flags)
{
	struct acpi_irq_parse_one_ctx ctx = { -EINVAL, index, flags, fwspec };

	acpi_walk_resources(handle, METHOD_NAME__CRS, acpi_irq_parse_one_cb, &ctx);
	return ctx.rc;
}

/**
 * acpi_irq_get - Lookup an ACPI IRQ resource and use it to initialize resource.
 * @handle: ACPI device handle
 * @index:  ACPI IRQ resource index to lookup
 * @res:    Linux IRQ resource to initialize
 *
 * Description:
 * Look for the ACPI IRQ resource with the given index and use it to initialize
 * the given Linux IRQ resource.
 *
 * Return:
 * 0 on success
 * -EINVAL if an error occurs
 * -EPROBE_DEFER if the IRQ lookup/conversion failed
 */
int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
{
	struct irq_fwspec fwspec;
	struct irq_domain *domain;
	unsigned long flags;
	int rc;

	rc = acpi_irq_parse_one(handle, index, &fwspec, &flags);
	if (rc)
		return rc;

	domain = irq_find_matching_fwnode(fwspec.fwnode, DOMAIN_BUS_ANY);
	if (!domain)
		return -EPROBE_DEFER;

	rc = irq_create_fwspec_mapping(&fwspec);
	if (rc <= 0)
		return -EINVAL;

	res->start = rc;
	res->end = rc;
	res->flags = flags;

	return 0;
}
EXPORT_SYMBOL_GPL(acpi_irq_get);

/**
 * acpi_set_irq_model - Setup the GSI irqdomain information
 * @model: the value assigned to acpi_irq_model
 * @fwnode: the irq_domain identifier for mapping and looking up
 *          GSI interrupts
 */
void __init acpi_set_irq_model(enum acpi_irq_model_id model,
			       struct fwnode_handle *fwnode)
{
	acpi_irq_model = model;
	acpi_gsi_domain_id = fwnode;
}
Commit	Line	Data
d44fa3d4 AVF	1	/*
	2	* ACPI GSI IRQ layer
	3	*
	4	* Copyright (C) 2015 ARM Ltd.
	5	* Author: Lorenzo Pieralisi <lorenzo.pieralisi@arm.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/acpi.h>
	12	#include <linux/irq.h>
	13	#include <linux/irqdomain.h>
	14	#include <linux/of.h>
	15
	16	enum acpi_irq_model_id acpi_irq_model;
	17
	18	static struct fwnode_handle *acpi_gsi_domain_id;
	19
	20	/**
	21	* acpi_gsi_to_irq() - Retrieve the linux irq number for a given GSI
	22	* @gsi: GSI IRQ number to map
	23	* @irq: pointer where linux IRQ number is stored
	24	*
	25	* irq location updated with irq value [>0 on success, 0 on failure]
	26	*
1dc482b6	27	* Returns: 0 on success
d44fa3d4 AVF	28	* -EINVAL on failure
	29	*/
	30	int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
	31	{
	32	struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id,
	33	DOMAIN_BUS_ANY);
	34
	35	*irq = irq_find_mapping(d, gsi);
	36	/*
	37	* *irq == 0 means no mapping, that should
	38	* be reported as a failure
	39	*/
1dc482b6	40	return (*irq > 0) ? 0 : -EINVAL;
d44fa3d4 AVF	41	}
	42	EXPORT_SYMBOL_GPL(acpi_gsi_to_irq);
	43
	44	/**
	45	* acpi_register_gsi() - Map a GSI to a linux IRQ number
	46	* @dev: device for which IRQ has to be mapped
	47	* @gsi: GSI IRQ number
	48	* @trigger: trigger type of the GSI number to be mapped
	49	* @polarity: polarity of the GSI to be mapped
	50	*
	51	* Returns: a valid linux IRQ number on success
	52	* -EINVAL on failure
	53	*/
	54	int acpi_register_gsi(struct device *dev, u32 gsi, int trigger,
	55	int polarity)
	56	{
	57	struct irq_fwspec fwspec;
	58
	59	if (WARN_ON(!acpi_gsi_domain_id)) {
	60	pr_warn("GSI: No registered irqchip, giving up\n");
	61	return -EINVAL;
	62	}
	63
	64	fwspec.fwnode = acpi_gsi_domain_id;
	65	fwspec.param[0] = gsi;
	66	fwspec.param[1] = acpi_dev_get_irq_type(trigger, polarity);
	67	fwspec.param_count = 2;
	68
	69	return irq_create_fwspec_mapping(&fwspec);
	70	}
	71	EXPORT_SYMBOL_GPL(acpi_register_gsi);
	72
	73	/**
	74	* acpi_unregister_gsi() - Free a GSI<->linux IRQ number mapping
	75	* @gsi: GSI IRQ number
	76	*/
	77	void acpi_unregister_gsi(u32 gsi)
	78	{
	79	struct irq_domain *d = irq_find_matching_fwnode(acpi_gsi_domain_id,
	80	DOMAIN_BUS_ANY);
	81	int irq = irq_find_mapping(d, gsi);
	82
	83	irq_dispose_mapping(irq);
	84	}
	85	EXPORT_SYMBOL_GPL(acpi_unregister_gsi);
	86
	87	/**
	88	* acpi_get_irq_source_fwhandle() - Retrieve fwhandle from IRQ resource source.
	89	* @source: acpi_resource_source to use for the lookup.
	90	*
	91	* Description:
	92	* Retrieve the fwhandle of the device referenced by the given IRQ resource
	93	* source.
	94	*
	95	* Return:
	96	* The referenced device fwhandle or NULL on failure
	97	*/
	98	static struct fwnode_handle *
	99	acpi_get_irq_source_fwhandle(const struct acpi_resource_source *source)
	100	{
	101	struct fwnode_handle *result;
	102	struct acpi_device *device;
	103	acpi_handle handle;
	104	acpi_status status;
105
106	if (!source->string_length)
107	return acpi_gsi_domain_id;
108
109	status = acpi_get_handle(NULL, source->string_ptr, &handle);
110	if (WARN_ON(ACPI_FAILURE(status)))
111	return NULL;
112
113	device = acpi_bus_get_acpi_device(handle);
114	if (WARN_ON(!device))
115	return NULL;
116
117	result = &device->fwnode;
118	acpi_bus_put_acpi_device(device);
119	return result;
120	}
121
122	/*
123	* Context for the resource walk used to lookup IRQ resources.
124	* Contains a return code, the lookup index, and references to the flags
125	* and fwspec where the result is returned.
126	*/
127	struct acpi_irq_parse_one_ctx {
128	int rc;
129	unsigned int index;
130	unsigned long *res_flags;
131	struct irq_fwspec *fwspec;
132	};
133
134	/**
135	* acpi_irq_parse_one_match - Handle a matching IRQ resource.
136	* @fwnode: matching fwnode
137	* @hwirq: hardware IRQ number
138	* @triggering: triggering attributes of hwirq
139	* @polarity: polarity attributes of hwirq
140	* @polarity: polarity attributes of hwirq
141	* @shareable: shareable attributes of hwirq
142	* @ctx: acpi_irq_parse_one_ctx updated by this function
143	*
144	* Description:
145	* Handle a matching IRQ resource by populating the given ctx with
146	* the information passed.
147	*/
148	static inline void acpi_irq_parse_one_match(struct fwnode_handle *fwnode,
149	u32 hwirq, u8 triggering,
150	u8 polarity, u8 shareable,
151	struct acpi_irq_parse_one_ctx *ctx)
152	{
153	if (!fwnode)
154	return;
155	ctx->rc = 0;
156	*ctx->res_flags = acpi_dev_irq_flags(triggering, polarity, shareable);
157	ctx->fwspec->fwnode = fwnode;
158	ctx->fwspec->param[0] = hwirq;
159	ctx->fwspec->param[1] = acpi_dev_get_irq_type(triggering, polarity);
160	ctx->fwspec->param_count = 2;
161	}
162
163	/**
164	* acpi_irq_parse_one_cb - Handle the given resource.
165	* @ares: resource to handle
166	* @context: context for the walk
167	*
168	* Description:
169	* This is called by acpi_walk_resources passing each resource returned by
170	* the _CRS method. We only inspect IRQ resources. Since IRQ resources
171	* might contain multiple interrupts we check if the index is within this
172	* one's interrupt array, otherwise we subtract the current resource IRQ
173	* count from the lookup index to prepare for the next resource.
174	* Once a match is found we call acpi_irq_parse_one_match to populate
175	* the result and end the walk by returning AE_CTRL_TERMINATE.
176	*
177	* Return:
178	* AE_OK if the walk should continue, AE_CTRL_TERMINATE if a matching
179	* IRQ resource was found.
180	*/
181	static acpi_status acpi_irq_parse_one_cb(struct acpi_resource *ares,
182	void *context)
183	{
184	struct acpi_irq_parse_one_ctx *ctx = context;
185	struct acpi_resource_irq *irq;
186	struct acpi_resource_extended_irq *eirq;
187	struct fwnode_handle *fwnode;
188
189	switch (ares->type) {
190	case ACPI_RESOURCE_TYPE_IRQ:
191	irq = &ares->data.irq;
192	if (ctx->index >= irq->interrupt_count) {
193	ctx->index -= irq->interrupt_count;
194	return AE_OK;
195	}
196	fwnode = acpi_gsi_domain_id;
197	acpi_irq_parse_one_match(fwnode, irq->interrupts[ctx->index],
198	irq->triggering, irq->polarity,
199	irq->sharable, ctx);
200	return AE_CTRL_TERMINATE;
201	case ACPI_RESOURCE_TYPE_EXTENDED_IRQ:
202	eirq = &ares->data.extended_irq;
203	if (eirq->producer_consumer == ACPI_PRODUCER)
204	return AE_OK;
205	if (ctx->index >= eirq->interrupt_count) {
206	ctx->index -= eirq->interrupt_count;
207	return AE_OK;
208	}
209	fwnode = acpi_get_irq_source_fwhandle(&eirq->resource_source);
210	acpi_irq_parse_one_match(fwnode, eirq->interrupts[ctx->index],
211	eirq->triggering, eirq->polarity,
212	eirq->sharable, ctx);
213	return AE_CTRL_TERMINATE;
214	}
215
216	return AE_OK;
217	}
218
219	/**
220	* acpi_irq_parse_one - Resolve an interrupt for a device
221	* @handle: the device whose interrupt is to be resolved
222	* @index: index of the interrupt to resolve
223	* @fwspec: structure irq_fwspec filled by this function
224	* @flags: resource flags filled by this function
225	*
226	* Description:
227	* Resolves an interrupt for a device by walking its CRS resources to find
228	* the appropriate ACPI IRQ resource and populating the given struct irq_fwspec
229	* and flags.
230	*
231	* Return:
232	* The result stored in ctx.rc by the callback, or the default -EINVAL value
233	* if an error occurs.
234	*/
235	static int acpi_irq_parse_one(acpi_handle handle, unsigned int index,
236	struct irq_fwspec fwspec, unsigned long flags)
237	{
238	struct acpi_irq_parse_one_ctx ctx = { -EINVAL, index, flags, fwspec };
239
240	acpi_walk_resources(handle, METHOD_NAME__CRS, acpi_irq_parse_one_cb, &ctx);
241	return ctx.rc;
242	}
243
244	/**
245	* acpi_irq_get - Lookup an ACPI IRQ resource and use it to initialize resource.
246	* @handle: ACPI device handle
247	* @index: ACPI IRQ resource index to lookup
248	* @res: Linux IRQ resource to initialize
249	*
250	* Description:
251	* Look for the ACPI IRQ resource with the given index and use it to initialize
252	* the given Linux IRQ resource.
253	*
254	* Return:
255	* 0 on success
256	* -EINVAL if an error occurs
257	* -EPROBE_DEFER if the IRQ lookup/conversion failed
258	*/
259	int acpi_irq_get(acpi_handle handle, unsigned int index, struct resource *res)
260	{
261	struct irq_fwspec fwspec;
262	struct irq_domain *domain;
263	unsigned long flags;
264	int rc;
265
266	rc = acpi_irq_parse_one(handle, index, &fwspec, &flags);
267	if (rc)
268	return rc;
269
270	domain = irq_find_matching_fwnode(fwspec.fwnode, DOMAIN_BUS_ANY);
271	if (!domain)
272	return -EPROBE_DEFER;
273
274	rc = irq_create_fwspec_mapping(&fwspec);
275	if (rc <= 0)
276	return -EINVAL;
277
278	res->start = rc;
279	res->end = rc;
280	res->flags = flags;
281
282	return 0;
283	}
284	EXPORT_SYMBOL_GPL(acpi_irq_get);
285
286	/**
287	* acpi_set_irq_model - Setup the GSI irqdomain information
288	* @model: the value assigned to acpi_irq_model
289	* @fwnode: the irq_domain identifier for mapping and looking up
290	* GSI interrupts
291	*/
292	void __init acpi_set_irq_model(enum acpi_irq_model_id model,
293	struct fwnode_handle *fwnode)
294	{
295	acpi_irq_model = model;
296	acpi_gsi_domain_id = fwnode;
297	}