diff options
Diffstat (limited to 'drivers/reset/hisilicon/reset-hi3660.c')
-rw-r--r-- | drivers/reset/hisilicon/reset-hi3660.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/reset/hisilicon/reset-hi3660.c b/drivers/reset/hisilicon/reset-hi3660.c new file mode 100644 index 000000000..17d8bb128 --- /dev/null +++ b/drivers/reset/hisilicon/reset-hi3660.c @@ -0,0 +1,126 @@ +/* + * Copyright (c) 2016-2017 Linaro Ltd. + * Copyright (c) 2016-2017 HiSilicon Technologies Co., Ltd. + * + * 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. + */ +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/reset-controller.h> + +struct hi3660_reset_controller { + struct reset_controller_dev rst; + struct regmap *map; +}; + +#define to_hi3660_reset_controller(_rst) \ + container_of(_rst, struct hi3660_reset_controller, rst) + +static int hi3660_reset_program_hw(struct reset_controller_dev *rcdev, + unsigned long idx, bool assert) +{ + struct hi3660_reset_controller *rc = to_hi3660_reset_controller(rcdev); + unsigned int offset = idx >> 8; + unsigned int mask = BIT(idx & 0x1f); + + if (assert) + return regmap_write(rc->map, offset, mask); + else + return regmap_write(rc->map, offset + 4, mask); +} + +static int hi3660_reset_assert(struct reset_controller_dev *rcdev, + unsigned long idx) +{ + return hi3660_reset_program_hw(rcdev, idx, true); +} + +static int hi3660_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long idx) +{ + return hi3660_reset_program_hw(rcdev, idx, false); +} + +static int hi3660_reset_dev(struct reset_controller_dev *rcdev, + unsigned long idx) +{ + int err; + + err = hi3660_reset_assert(rcdev, idx); + if (err) + return err; + + return hi3660_reset_deassert(rcdev, idx); +} + +static struct reset_control_ops hi3660_reset_ops = { + .reset = hi3660_reset_dev, + .assert = hi3660_reset_assert, + .deassert = hi3660_reset_deassert, +}; + +static int hi3660_reset_xlate(struct reset_controller_dev *rcdev, + const struct of_phandle_args *reset_spec) +{ + unsigned int offset, bit; + + offset = reset_spec->args[0]; + bit = reset_spec->args[1]; + + return (offset << 8) | bit; +} + +static int hi3660_reset_probe(struct platform_device *pdev) +{ + struct hi3660_reset_controller *rc; + struct device_node *np = pdev->dev.of_node; + struct device *dev = &pdev->dev; + + rc = devm_kzalloc(dev, sizeof(*rc), GFP_KERNEL); + if (!rc) + return -ENOMEM; + + rc->map = syscon_regmap_lookup_by_phandle(np, "hisi,rst-syscon"); + if (IS_ERR(rc->map)) { + dev_err(dev, "failed to get hi3660,rst-syscon\n"); + return PTR_ERR(rc->map); + } + + rc->rst.ops = &hi3660_reset_ops, + rc->rst.of_node = np; + rc->rst.of_reset_n_cells = 2; + rc->rst.of_xlate = hi3660_reset_xlate; + + return reset_controller_register(&rc->rst); +} + +static const struct of_device_id hi3660_reset_match[] = { + { .compatible = "hisilicon,hi3660-reset", }, + {}, +}; +MODULE_DEVICE_TABLE(of, hi3660_reset_match); + +static struct platform_driver hi3660_reset_driver = { + .probe = hi3660_reset_probe, + .driver = { + .name = "hi3660-reset", + .of_match_table = hi3660_reset_match, + }, +}; + +static int __init hi3660_reset_init(void) +{ + return platform_driver_register(&hi3660_reset_driver); +} +arch_initcall(hi3660_reset_init); + +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:hi3660-reset"); +MODULE_DESCRIPTION("HiSilicon Hi3660 Reset Driver"); |