[deliverable/linux.git] / drivers / power / reset / xgene-reboot.c

/*
 * AppliedMicro X-Gene SoC Reboot Driver
 *
 * Copyright (c) 2013, Applied Micro Circuits Corporation
 * Author: Feng Kan <fkan@apm.com>
 * Author: Loc Ho <lho@apm.com>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of
 * the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 * MA 02111-1307 USA
 *
 * This driver provides system reboot functionality for APM X-Gene SoC.
 * For system shutdown, this is board specify. If a board designer
 * implements GPIO shutdown, use the gpio-poweroff.c driver.
 */
#include <linux/delay.h>
#include <linux/io.h>
#include <linux/notifier.h>
#include <linux/of_device.h>
#include <linux/of_address.h>
#include <linux/platform_device.h>
#include <linux/reboot.h>
#include <linux/stat.h>
#include <linux/slab.h>

struct xgene_reboot_context {
	struct device *dev;
	void *csr;
	u32 mask;
	struct notifier_block restart_handler;
};

static int xgene_restart_handler(struct notifier_block *this,
				 unsigned long mode, void *cmd)
{
	struct xgene_reboot_context *ctx =
		container_of(this, struct xgene_reboot_context,
			     restart_handler);

	/* Issue the reboot */
	writel(ctx->mask, ctx->csr);

	mdelay(1000);

	dev_emerg(ctx->dev, "Unable to restart system\n");

	return NOTIFY_DONE;
}

static int xgene_reboot_probe(struct platform_device *pdev)
{
	struct xgene_reboot_context *ctx;
	struct device *dev = &pdev->dev;
	int err;

	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;

	ctx->csr = of_iomap(dev->of_node, 0);
	if (!ctx->csr) {
		dev_err(dev, "can not map resource\n");
		return -ENODEV;
	}

	if (of_property_read_u32(dev->of_node, "mask", &ctx->mask))
		ctx->mask = 0xFFFFFFFF;

	ctx->dev = dev;
	ctx->restart_handler.notifier_call = xgene_restart_handler;
	ctx->restart_handler.priority = 128;
	err = register_restart_handler(&ctx->restart_handler);
	if (err)
		dev_err(dev, "cannot register restart handler (err=%d)\n", err);

	return err;
}

static const struct of_device_id xgene_reboot_of_match[] = {
	{ .compatible = "apm,xgene-reboot" },
	{}
};

static struct platform_driver xgene_reboot_driver = {
	.probe = xgene_reboot_probe,
	.driver = {
		.name = "xgene-reboot",
		.of_match_table = xgene_reboot_of_match,
	},
};

static int __init xgene_reboot_init(void)
{
	return platform_driver_register(&xgene_reboot_driver);
}
device_initcall(xgene_reboot_init);
Commit	Line	Data
67778e0e LH	1	/*
	2	* AppliedMicro X-Gene SoC Reboot Driver
	3	*
	4	* Copyright (c) 2013, Applied Micro Circuits Corporation
	5	* Author: Feng Kan <fkan@apm.com>
	6	* Author: Loc Ho <lho@apm.com>
	7	*
	8	* This program is free software; you can redistribute it and/or
	9	* modify it under the terms of the GNU General Public License as
	10	* published by the Free Software Foundation; either version 2 of
	11	* the License, or (at your option) any later version.
	12	*
	13	* This program is distributed in the hope that it will be useful,
	14	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	15	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	16	* GNU General Public License for more details.
	17	*
	18	* You should have received a copy of the GNU General Public License
	19	* along with this program; if not, write to the Free Software
	20	* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
	21	* MA 02111-1307 USA
	22	*
	23	* This driver provides system reboot functionality for APM X-Gene SoC.
	24	* For system shutdown, this is board specify. If a board designer
	25	* implements GPIO shutdown, use the gpio-poweroff.c driver.
	26	*/
745e1976	27	#include <linux/delay.h>
67778e0e	28	#include <linux/io.h>
8f57f231	29	#include <linux/notifier.h>
67778e0e LH	30	#include <linux/of_device.h>
	31	#include <linux/of_address.h>
	32	#include <linux/platform_device.h>
8f57f231	33	#include <linux/reboot.h>
67778e0e LH	34	#include <linux/stat.h>
67778e0e LH	35	#include <linux/slab.h>
67778e0e LH	36
67778e0e LH	37	struct xgene_reboot_context {
43160718	38	struct device *dev;
67778e0e LH	39	void *csr;
67778e0e LH	40	u32 mask;
8f57f231	41	struct notifier_block restart_handler;
67778e0e LH	42	};
67778e0e LH	43
8f57f231 GR	44	static int xgene_restart_handler(struct notifier_block *this,
8f57f231 GR	45	unsigned long mode, void *cmd)
67778e0e	46	{
8f57f231 GR	47	struct xgene_reboot_context *ctx =
	48	container_of(this, struct xgene_reboot_context,
	49	restart_handler);
67778e0e LH	50
67778e0e LH	51	/* Issue the reboot */
8f57f231	52	writel(ctx->mask, ctx->csr);
67778e0e	53
745e1976	54	mdelay(1000);
67778e0e	55
43160718	56	dev_emerg(ctx->dev, "Unable to restart system\n");
8f57f231 GR	57
8f57f231 GR	58	return NOTIFY_DONE;
67778e0e LH	59	}
	60
	61	static int xgene_reboot_probe(struct platform_device *pdev)
	62	{
	63	struct xgene_reboot_context *ctx;
43160718	64	struct device *dev = &pdev->dev;
8f57f231	65	int err;
67778e0e	66
43160718	67	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
ef288f9f GR	68	if (!ctx)
ef288f9f GR	69	return -ENOMEM;
67778e0e	70
43160718	71	ctx->csr = of_iomap(dev->of_node, 0);
67778e0e	72	if (!ctx->csr) {
43160718	73	dev_err(dev, "can not map resource\n");
67778e0e LH	74	return -ENODEV;
	75	}
	76
43160718	77	if (of_property_read_u32(dev->of_node, "mask", &ctx->mask))
67778e0e LH	78	ctx->mask = 0xFFFFFFFF;
67778e0e LH	79
43160718	80	ctx->dev = dev;
8f57f231 GR	81	ctx->restart_handler.notifier_call = xgene_restart_handler;
	82	ctx->restart_handler.priority = 128;
	83	err = register_restart_handler(&ctx->restart_handler);
	84	if (err)
	85	dev_err(dev, "cannot register restart handler (err=%d)\n", err);
67778e0e	86
8f57f231	87	return err;
67778e0e LH	88	}
67778e0e LH	89
8fb08855	90	static const struct of_device_id xgene_reboot_of_match[] = {
67778e0e LH	91	{ .compatible = "apm,xgene-reboot" },
	92	{}
	93	};
	94
	95	static struct platform_driver xgene_reboot_driver = {
	96	.probe = xgene_reboot_probe,
	97	.driver = {
	98	.name = "xgene-reboot",
	99	.of_match_table = xgene_reboot_of_match,
	100	},
	101	};
	102
	103	static int __init xgene_reboot_init(void)
	104	{
	105	return platform_driver_register(&xgene_reboot_driver);
	106	}
	107	device_initcall(xgene_reboot_init);