19952f691SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
262700682SThor Thayer /*
362700682SThor Thayer * Copyright Intel Corporation (C) 2017. All Rights Reserved
462700682SThor Thayer *
562700682SThor Thayer * Reset driver for Altera Arria10 MAX5 System Resource Chip
662700682SThor Thayer *
762700682SThor Thayer * Adapted from reset-socfpga.c
862700682SThor Thayer */
962700682SThor Thayer
1062700682SThor Thayer #include <linux/err.h>
1162700682SThor Thayer #include <linux/mfd/altera-a10sr.h>
1262700682SThor Thayer #include <linux/module.h>
1362700682SThor Thayer #include <linux/of.h>
1462700682SThor Thayer #include <linux/platform_device.h>
1562700682SThor Thayer #include <linux/reset-controller.h>
1662700682SThor Thayer
1762700682SThor Thayer #include <dt-bindings/reset/altr,rst-mgr-a10sr.h>
1862700682SThor Thayer
1962700682SThor Thayer struct a10sr_reset {
2062700682SThor Thayer struct reset_controller_dev rcdev;
2162700682SThor Thayer struct regmap *regmap;
2262700682SThor Thayer };
2362700682SThor Thayer
to_a10sr_rst(struct reset_controller_dev * rc)2462700682SThor Thayer static inline struct a10sr_reset *to_a10sr_rst(struct reset_controller_dev *rc)
2562700682SThor Thayer {
2662700682SThor Thayer return container_of(rc, struct a10sr_reset, rcdev);
2762700682SThor Thayer }
2862700682SThor Thayer
a10sr_reset_shift(unsigned long id)2962700682SThor Thayer static inline int a10sr_reset_shift(unsigned long id)
3062700682SThor Thayer {
3162700682SThor Thayer switch (id) {
3262700682SThor Thayer case A10SR_RESET_ENET_HPS:
3362700682SThor Thayer return 1;
3462700682SThor Thayer case A10SR_RESET_PCIE:
3562700682SThor Thayer case A10SR_RESET_FILE:
3662700682SThor Thayer case A10SR_RESET_BQSPI:
3762700682SThor Thayer case A10SR_RESET_USB:
3862700682SThor Thayer return id + 11;
3962700682SThor Thayer default:
4062700682SThor Thayer return -EINVAL;
4162700682SThor Thayer }
4262700682SThor Thayer }
4362700682SThor Thayer
a10sr_reset_update(struct reset_controller_dev * rcdev,unsigned long id,bool assert)4462700682SThor Thayer static int a10sr_reset_update(struct reset_controller_dev *rcdev,
4562700682SThor Thayer unsigned long id, bool assert)
4662700682SThor Thayer {
4762700682SThor Thayer struct a10sr_reset *a10r = to_a10sr_rst(rcdev);
4862700682SThor Thayer int offset = a10sr_reset_shift(id);
4962700682SThor Thayer u8 mask = ALTR_A10SR_REG_BIT_MASK(offset);
5062700682SThor Thayer int index = ALTR_A10SR_HPS_RST_REG + ALTR_A10SR_REG_OFFSET(offset);
5162700682SThor Thayer
5262700682SThor Thayer return regmap_update_bits(a10r->regmap, index, mask, assert ? 0 : mask);
5362700682SThor Thayer }
5462700682SThor Thayer
a10sr_reset_assert(struct reset_controller_dev * rcdev,unsigned long id)5562700682SThor Thayer static int a10sr_reset_assert(struct reset_controller_dev *rcdev,
5662700682SThor Thayer unsigned long id)
5762700682SThor Thayer {
5862700682SThor Thayer return a10sr_reset_update(rcdev, id, true);
5962700682SThor Thayer }
6062700682SThor Thayer
a10sr_reset_deassert(struct reset_controller_dev * rcdev,unsigned long id)6162700682SThor Thayer static int a10sr_reset_deassert(struct reset_controller_dev *rcdev,
6262700682SThor Thayer unsigned long id)
6362700682SThor Thayer {
6462700682SThor Thayer return a10sr_reset_update(rcdev, id, false);
6562700682SThor Thayer }
6662700682SThor Thayer
a10sr_reset_status(struct reset_controller_dev * rcdev,unsigned long id)6762700682SThor Thayer static int a10sr_reset_status(struct reset_controller_dev *rcdev,
6862700682SThor Thayer unsigned long id)
6962700682SThor Thayer {
7062700682SThor Thayer int ret;
7162700682SThor Thayer struct a10sr_reset *a10r = to_a10sr_rst(rcdev);
7262700682SThor Thayer int offset = a10sr_reset_shift(id);
7362700682SThor Thayer u8 mask = ALTR_A10SR_REG_BIT_MASK(offset);
7462700682SThor Thayer int index = ALTR_A10SR_HPS_RST_REG + ALTR_A10SR_REG_OFFSET(offset);
7562700682SThor Thayer unsigned int value;
7662700682SThor Thayer
7762700682SThor Thayer ret = regmap_read(a10r->regmap, index, &value);
7862700682SThor Thayer if (ret < 0)
7962700682SThor Thayer return ret;
8062700682SThor Thayer
8162700682SThor Thayer return !!(value & mask);
8262700682SThor Thayer }
8362700682SThor Thayer
8462700682SThor Thayer static const struct reset_control_ops a10sr_reset_ops = {
8562700682SThor Thayer .assert = a10sr_reset_assert,
8662700682SThor Thayer .deassert = a10sr_reset_deassert,
8762700682SThor Thayer .status = a10sr_reset_status,
8862700682SThor Thayer };
8962700682SThor Thayer
a10sr_reset_probe(struct platform_device * pdev)9062700682SThor Thayer static int a10sr_reset_probe(struct platform_device *pdev)
9162700682SThor Thayer {
9262700682SThor Thayer struct altr_a10sr *a10sr = dev_get_drvdata(pdev->dev.parent);
9362700682SThor Thayer struct a10sr_reset *a10r;
9462700682SThor Thayer
9562700682SThor Thayer a10r = devm_kzalloc(&pdev->dev, sizeof(struct a10sr_reset),
9662700682SThor Thayer GFP_KERNEL);
9762700682SThor Thayer if (!a10r)
9862700682SThor Thayer return -ENOMEM;
9962700682SThor Thayer
10062700682SThor Thayer a10r->rcdev.owner = THIS_MODULE;
10162700682SThor Thayer a10r->rcdev.nr_resets = A10SR_RESET_NUM;
10262700682SThor Thayer a10r->rcdev.ops = &a10sr_reset_ops;
10362700682SThor Thayer a10r->rcdev.of_node = pdev->dev.of_node;
10462700682SThor Thayer a10r->regmap = a10sr->regmap;
10562700682SThor Thayer
10662700682SThor Thayer platform_set_drvdata(pdev, a10r);
10762700682SThor Thayer
10862700682SThor Thayer return devm_reset_controller_register(&pdev->dev, &a10r->rcdev);
10962700682SThor Thayer }
11062700682SThor Thayer
11162700682SThor Thayer static const struct of_device_id a10sr_reset_of_match[] = {
11262700682SThor Thayer { .compatible = "altr,a10sr-reset" },
11362700682SThor Thayer { },
11462700682SThor Thayer };
11562700682SThor Thayer MODULE_DEVICE_TABLE(of, a10sr_reset_of_match);
11662700682SThor Thayer
11762700682SThor Thayer static struct platform_driver a10sr_reset_driver = {
11862700682SThor Thayer .probe = a10sr_reset_probe,
11962700682SThor Thayer .driver = {
12062700682SThor Thayer .name = "altr_a10sr_reset",
121*466ba3c8SKrzysztof Kozlowski .of_match_table = a10sr_reset_of_match,
12262700682SThor Thayer },
12362700682SThor Thayer };
12462700682SThor Thayer module_platform_driver(a10sr_reset_driver);
12562700682SThor Thayer
12662700682SThor Thayer MODULE_AUTHOR("Thor Thayer <thor.thayer@linux.intel.com>");
12762700682SThor Thayer MODULE_DESCRIPTION("Altera Arria10 System Resource Reset Controller Driver");
12862700682SThor Thayer MODULE_LICENSE("GPL v2");
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