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1527058736
Add hi3660 reset driver
Example of dts usage:
iomcu_rst: iomcu_rst_controller {
compatible = "hisilicon,hi3660-reset";
hisi,rst-syscon = <&iomcu>;
#reset-cells = <2>;
};
i2c0: i2c@..... {
...
resets = <&iomcu_rst 0x20 3>; /* offset: 0x20; bit: 3 */
...
};
Signed-off-by: Zhangfei Gao <zhangfei.gao@linaro.org>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
127 lines
3.2 KiB
C
127 lines
3.2 KiB
C
/*
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* Copyright (c) 2016-2017 Linaro Ltd.
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* Copyright (c) 2016-2017 HiSilicon Technologies Co., Ltd.
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*/
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#include <linux/kernel.h>
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#include <linux/mfd/syscon.h>
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#include <linux/module.h>
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#include <linux/of_device.h>
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#include <linux/platform_device.h>
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#include <linux/regmap.h>
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#include <linux/reset-controller.h>
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struct hi3660_reset_controller {
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struct reset_controller_dev rst;
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struct regmap *map;
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};
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#define to_hi3660_reset_controller(_rst) \
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container_of(_rst, struct hi3660_reset_controller, rst)
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static int hi3660_reset_program_hw(struct reset_controller_dev *rcdev,
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unsigned long idx, bool assert)
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{
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struct hi3660_reset_controller *rc = to_hi3660_reset_controller(rcdev);
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unsigned int offset = idx >> 8;
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unsigned int mask = BIT(idx & 0x1f);
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if (assert)
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return regmap_write(rc->map, offset, mask);
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else
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return regmap_write(rc->map, offset + 4, mask);
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}
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static int hi3660_reset_assert(struct reset_controller_dev *rcdev,
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unsigned long idx)
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{
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return hi3660_reset_program_hw(rcdev, idx, true);
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}
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static int hi3660_reset_deassert(struct reset_controller_dev *rcdev,
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unsigned long idx)
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{
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return hi3660_reset_program_hw(rcdev, idx, false);
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}
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static int hi3660_reset_dev(struct reset_controller_dev *rcdev,
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unsigned long idx)
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{
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int err;
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err = hi3660_reset_assert(rcdev, idx);
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if (err)
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return err;
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return hi3660_reset_deassert(rcdev, idx);
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}
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static struct reset_control_ops hi3660_reset_ops = {
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.reset = hi3660_reset_dev,
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.assert = hi3660_reset_assert,
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.deassert = hi3660_reset_deassert,
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};
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static int hi3660_reset_xlate(struct reset_controller_dev *rcdev,
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const struct of_phandle_args *reset_spec)
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{
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unsigned int offset, bit;
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offset = reset_spec->args[0];
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bit = reset_spec->args[1];
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return (offset << 8) | bit;
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}
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static int hi3660_reset_probe(struct platform_device *pdev)
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{
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struct hi3660_reset_controller *rc;
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struct device_node *np = pdev->dev.of_node;
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struct device *dev = &pdev->dev;
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rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL);
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if (!rc)
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return -ENOMEM;
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rc->map = syscon_regmap_lookup_by_phandle(np, "hisi,rst-syscon");
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if (IS_ERR(rc->map)) {
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dev_err(dev, "failed to get hi3660,rst-syscon\n");
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return PTR_ERR(rc->map);
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}
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rc->rst.ops = &hi3660_reset_ops,
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rc->rst.of_node = np;
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rc->rst.of_reset_n_cells = 2;
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rc->rst.of_xlate = hi3660_reset_xlate;
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return reset_controller_register(&rc->rst);
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}
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static const struct of_device_id hi3660_reset_match[] = {
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{ .compatible = "hisilicon,hi3660-reset", },
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{},
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};
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MODULE_DEVICE_TABLE(of, hi3660_reset_match);
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static struct platform_driver hi3660_reset_driver = {
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.probe = hi3660_reset_probe,
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.driver = {
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.name = "hi3660-reset",
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.of_match_table = hi3660_reset_match,
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},
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};
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static int __init hi3660_reset_init(void)
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{
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return platform_driver_register(&hi3660_reset_driver);
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}
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arch_initcall(hi3660_reset_init);
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MODULE_LICENSE("GPL");
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MODULE_ALIAS("platform:hi3660-reset");
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MODULE_DESCRIPTION("HiSilicon Hi3660 Reset Driver");
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