linux/drivers/irqchip/irqchip.h

/*
 * Copyright (C) 2012 Thomas Petazzoni
 *
 * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
 *
 * This file is licensed under the terms of the GNU General Public
 * License version 2.  This program is licensed "as is" without any
 * warranty of any kind, whether express or implied.
 */

#ifndef _IRQCHIP_H
#define _IRQCHIP_H

/*
 * This macro must be used by the different irqchip drivers to declare
 * the association between their DT compatible string and their
 * initialization function.
 *
 * @name: name that must be unique accross all IRQCHIP_DECLARE of the
 * same file.
 * @compstr: compatible string of the irqchip driver
 * @fn: initialization function
 */
#define IRQCHIP_DECLARE(name,compstr,fn)				\
	static const struct of_device_id irqchip_of_match_##name	\
	__used __section(__irqchip_of_table)				\
	= { .compatible = compstr, .data = fn }

#endif
irqchip: add basic infrastructure With the recent creation of the drivers/irqchip/ directory, it is desirable to move irq controller drivers here. At the moment, the only driver here is irq-bcm2835, the driver for the irq controller found in the ARM BCM2835 SoC, present in Rasberry Pi systems. This irq controller driver was exporting its initialization function and its irq handling function through a header file in <linux/irqchip/bcm2835.h>. When proposing to also move another irq controller driver in drivers/irqchip, Rob Herring raised the very valid point that moving things to drivers/irqchip was good in order to remove more stuff from arch/arm, but if it means adding gazillions of headers files in include/linux/irqchip/, it would not be very nice. So, upon the suggestion of Rob Herring and Arnd Bergmann, this commit introduces a small infrastructure that defines a central irqchip_init() function in drivers/irqchip/irqchip.c, which is meant to be called as the ->init_irq() callback of ARM platforms. This function calls of_irq_init() with an array of match strings and init functions generated from a special linker section. Note that the irq controller driver initialization function is responsible for setting the global handle_arch_irq() variable, so that ARM platforms no longer have to define the ->handle_irq field in their DT_MACHINE structure. A global header, <linux/irqchip.h> is also added to expose the single irqchip_init() function to the reset of the kernel. A further commit moves the BCM2835 irq controller driver to this new small infrastructure, therefore removing the include/linux/irqchip/ directory. Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Reviewed-by: Stephen Warren <swarren@wwwdotorg.org> Reviewed-by: Rob Herring <rob.herring@calxeda.com> Acked-by: Arnd Bergmann <arnd@arndb.de> [rob.herring: reword commit message to reflect use of linker sections.] Signed-off-by: Rob Herring <rob.herring@calxeda.com> 2012-11-21 06:00:52 +08:00			`/*`
			`* Copyright (C) 2012 Thomas Petazzoni`
			`*`
			`* Thomas Petazzoni <thomas.petazzoni@free-electrons.com>`
			`*`
			`* This file is licensed under the terms of the GNU General Public`
			`* License version 2. This program is licensed "as is" without any`
			`* warranty of any kind, whether express or implied.`
			`*/`

			`#ifndef _IRQCHIP_H`
			`#define _IRQCHIP_H`

			`/*`
			`* This macro must be used by the different irqchip drivers to declare`
			`* the association between their DT compatible string and their`
			`* initialization function.`
			`*`
			`* @name: name that must be unique accross all IRQCHIP_DECLARE of the`
			`* same file.`
			`* @compstr: compatible string of the irqchip driver`
			`* @fn: initialization function`
			`*/`
			`#define IRQCHIP_DECLARE(name,compstr,fn) \`
			`static const struct of_device_id irqchip_of_match_##name \`
			`__used __section(__irqchip_of_table) \`
			`= { .compatible = compstr, .data = fn }`

			`#endif`