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Commit 6e667fac authored by Neil Armstrong's avatar Neil Armstrong Committed by Philipp Zabel
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reset: Add Oxford Semiconductor Reset Controller driver 



Add System reset controller driver for Oxford Semiconductor OXNAS SoC
Family.

CC: Ma Haijun <mahaijuns@gmail.com>
Signed-off-by: default avatarNeil Armstrong <narmstrong@baylibre.com>
Signed-off-by: default avatarPhilipp Zabel <p.zabel@pengutronix.de>
parent 773fe726

drivers/reset/Kconfig

+3 −0
Original line number Diff line number Diff line
@@ -12,5 +12,8 @@ menuconfig RESET_CONTROLLER 


	  If unsure, say no.



config RESET_OXNAS

	bool



source "drivers/reset/sti/Kconfig"

source "drivers/reset/hisilicon/Kconfig"

drivers/reset/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -8,3 +8,4 @@ obj-$(CONFIG_ARCH_STI) += sti/ 
obj-$(CONFIG_ARCH_HISI) += hisilicon/

obj-$(CONFIG_ARCH_ZYNQ) += reset-zynq.o

obj-$(CONFIG_ATH79) += reset-ath79.o

obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o

drivers/reset/reset-oxnas.c

0 → 100644
+136 −0
Original line number Diff line number Diff line 
/*

 * drivers/reset/reset-oxnas.c

 *

 * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>

 * Copyright (C) 2014 Ma Haijun <mahaijuns@gmail.com>

 * Copyright (C) 2009 Oxford Semiconductor Ltd

 *

 * This program is free software; you can redistribute it and/or modify it

 * under the terms and conditions of the GNU General Public License,

 * version 2, as published by the Free Software Foundation.

 *

 * This program is distributed in the hope 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, see <http://www.gnu.org/licenses/>.

 */

#include <linux/err.h>

#include <linux/module.h>

#include <linux/of.h>

#include <linux/platform_device.h>

#include <linux/reset-controller.h>

#include <linux/slab.h>

#include <linux/delay.h>

#include <linux/types.h>

#include <linux/regmap.h>

#include <linux/mfd/syscon.h>



/* Regmap offsets */

#define RST_SET_REGOFFSET	0x34

#define RST_CLR_REGOFFSET	0x38



struct oxnas_reset {

	struct regmap *regmap;

	struct reset_controller_dev rcdev;

};



static int oxnas_reset_reset(struct reset_controller_dev *rcdev,

			      unsigned long id)

{

	struct oxnas_reset *data =

		container_of(rcdev, struct oxnas_reset, rcdev);



	regmap_write(data->regmap, RST_SET_REGOFFSET, BIT(id));

	msleep(50);

	regmap_write(data->regmap, RST_CLR_REGOFFSET, BIT(id));



	return 0;

}



static int oxnas_reset_assert(struct reset_controller_dev *rcdev,

			      unsigned long id)

{

	struct oxnas_reset *data =

		container_of(rcdev, struct oxnas_reset, rcdev);



	regmap_write(data->regmap, RST_SET_REGOFFSET, BIT(id));



	return 0;

}



static int oxnas_reset_deassert(struct reset_controller_dev *rcdev,

				unsigned long id)

{

	struct oxnas_reset *data =

		container_of(rcdev, struct oxnas_reset, rcdev);



	regmap_write(data->regmap, RST_CLR_REGOFFSET, BIT(id));



	return 0;

}



static const struct reset_control_ops oxnas_reset_ops = {

	.reset		= oxnas_reset_reset,

	.assert		= oxnas_reset_assert,

	.deassert	= oxnas_reset_deassert,

};



static const struct of_device_id oxnas_reset_dt_ids[] = {

	 { .compatible = "oxsemi,ox810se-reset", },

	 { /* sentinel */ },

};

MODULE_DEVICE_TABLE(of, oxnas_reset_dt_ids);



static int oxnas_reset_probe(struct platform_device *pdev)

{

	struct oxnas_reset *data;

	struct device *parent;



	parent = pdev->dev.parent;

	if (!parent) {

		dev_err(&pdev->dev, "no parent\n");

		return -ENODEV;

	}



	data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL);

	if (!data)

		return -ENOMEM;



	data->regmap = syscon_node_to_regmap(parent->of_node);

	if (IS_ERR(data->regmap)) {

		dev_err(&pdev->dev, "failed to get parent regmap\n");

		return PTR_ERR(data->regmap);

	}



	platform_set_drvdata(pdev, data);



	data->rcdev.owner = THIS_MODULE;

	data->rcdev.nr_resets = 32;

	data->rcdev.ops = &oxnas_reset_ops;

	data->rcdev.of_node = pdev->dev.of_node;



	return reset_controller_register(&data->rcdev);

}



static int oxnas_reset_remove(struct platform_device *pdev)

{

	struct oxnas_reset *data = platform_get_drvdata(pdev);



	reset_controller_unregister(&data->rcdev);



	return 0;

}



static struct platform_driver oxnas_reset_driver = {

	.probe	= oxnas_reset_probe,

	.remove	= oxnas_reset_remove,

	.driver = {

		.name		= "oxnas-reset",

		.of_match_table	= oxnas_reset_dt_ids,

	},

};



module_platform_driver(oxnas_reset_driver);