text: /*
   * Hisilicon Hi6220 reset controller driver
   *
   * Copyright (c) 2016 Linaro Limited.
   * Copyright (c) 2015-2016 Hisilicon Limited.
   *
   * Author: Feng Chen <puck.chen@hisilicon.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/io.h>
  #include <linux/init.h>
  #include <linux/module.h>
  #include <linux/bitops.h>
  #include <linux/of.h>
  #include <linux/of_device.h>
  #include <linux/regmap.h>
  #include <linux/mfd/syscon.h>
  #include <linux/reset-controller.h>
  #include <linux/reset.h>
  #include <linux/platform_device.h>
  
  #define PERIPH_ASSERT_OFFSET      0x300
  #define PERIPH_DEASSERT_OFFSET    0x304
  #define PERIPH_MAX_INDEX          0x509
  
  #define SC_MEDIA_RSTEN            0x052C
  #define SC_MEDIA_RSTDIS           0x0530
  #define MEDIA_MAX_INDEX           8
  
  #define to_reset_data(x) container_of(x, struct hi6220_reset_data, rc_dev)
  
  enum hi6220_reset_ctrl_type {
  	PERIPHERAL,
  	MEDIA,
  };
  
  struct hi6220_reset_data {
  	struct reset_controller_dev rc_dev;
  	struct regmap *regmap;
  };
  
  static int hi6220_peripheral_assert(struct reset_controller_dev *rc_dev,
  				    unsigned long idx)
  {
  	struct hi6220_reset_data *data = to_reset_data(rc_dev);
  	struct regmap *regmap = data->regmap;
  	u32 bank = idx >> 8;
  	u32 offset = idx & 0xff;
  	u32 reg = PERIPH_ASSERT_OFFSET + bank * 0x10;
  
  	return regmap_write(regmap, reg, BIT(offset));
  }
  
  static int hi6220_peripheral_deassert(struct reset_controller_dev *rc_dev,
  				      unsigned long idx)
  {
  	struct hi6220_reset_data *data = to_reset_data(rc_dev);
  	struct regmap *regmap = data->regmap;
  	u32 bank = idx >> 8;
  	u32 offset = idx & 0xff;
  	u32 reg = PERIPH_DEASSERT_OFFSET + bank * 0x10;
  
  	return regmap_write(regmap, reg, BIT(offset));
  }
  
  static const struct reset_control_ops hi6220_peripheral_reset_ops = {
  	.assert = hi6220_peripheral_assert,
  	.deassert = hi6220_peripheral_deassert,
  };
  
  static int hi6220_media_assert(struct reset_controller_dev *rc_dev,
  			       unsigned long idx)
  {
  	struct hi6220_reset_data *data = to_reset_data(rc_dev);
  	struct regmap *regmap = data->regmap;
  
  	return regmap_write(regmap, SC_MEDIA_RSTEN, BIT(idx));
  }
  
  static int hi6220_media_deassert(struct reset_controller_dev *rc_dev,
  				 unsigned long idx)
  {
  	struct hi6220_reset_data *data = to_reset_data(rc_dev);
  	struct regmap *regmap = data->regmap;
  
  	return regmap_write(regmap, SC_MEDIA_RSTDIS, BIT(idx));
  }
  
  static const struct reset_control_ops hi6220_media_reset_ops = {
  	.assert = hi6220_media_assert,
  	.deassert = hi6220_media_deassert,
  };
  
  static int hi6220_reset_probe(struct platform_device *pdev)
  {
  	struct device_node *np = pdev->dev.of_node;
  	struct device *dev = &pdev->dev;
  	enum hi6220_reset_ctrl_type type;
  	struct hi6220_reset_data *data;
  	struct regmap *regmap;
  
  	data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
  	if (!data)
  		return -ENOMEM;
  
  	type = (enum hi6220_reset_ctrl_type)of_device_get_match_data(dev);
  
  	regmap = syscon_node_to_regmap(np);
  	if (IS_ERR(regmap)) {
  		dev_err(dev, "failed to get reset controller regmap\n");
  		return PTR_ERR(regmap);
  	}
  
  	data->regmap = regmap;
  	data->rc_dev.of_node = np;
  	if (type == MEDIA) {
  		data->rc_dev.ops = &hi6220_media_reset_ops;
  		data->rc_dev.nr_resets = MEDIA_MAX_INDEX;
  	} else {
  		data->rc_dev.ops = &hi6220_peripheral_reset_ops;
  		data->rc_dev.nr_resets = PERIPH_MAX_INDEX;
  	}
  
  	return reset_controller_register(&data->rc_dev);
  }
  
  static const struct of_device_id hi6220_reset_match[] = {
  	{
  		.compatible = "hisilicon,hi6220-sysctrl",
  		.data = (void *)PERIPHERAL,
  	},
  	{
  		.compatible = "hisilicon,hi6220-mediactrl",
  		.data = (void *)MEDIA,
  	},
  	{ /* sentinel */ },
  };
  MODULE_DEVICE_TABLE(of, hi6220_reset_match);
  
  static struct platform_driver hi6220_reset_driver = {
  	.probe = hi6220_reset_probe,
  	.driver = {
  		.name = "reset-hi6220",
  		.of_match_table = hi6220_reset_match,
  	},
  };
  
  static int __init hi6220_reset_init(void)
  {
  	return platform_driver_register(&hi6220_reset_driver);
  }
  
  postcore_initcall(hi6220_reset_init);
  