diff options
Diffstat (limited to 'drivers/clk/mediatek/reset.c')
-rw-r--r-- | drivers/clk/mediatek/reset.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/drivers/clk/mediatek/reset.c b/drivers/clk/mediatek/reset.c new file mode 100644 index 000000000..9e9fe4b19 --- /dev/null +++ b/drivers/clk/mediatek/reset.c @@ -0,0 +1,97 @@ +/* + * Copyright (c) 2014 MediaTek Inc. + * + * 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. + * + * This program is distributed in the hope that 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. + */ + +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/regmap.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> + +#include "clk-mtk.h" + +struct mtk_reset { + struct regmap *regmap; + int regofs; + struct reset_controller_dev rcdev; +}; + +static int mtk_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev); + + return regmap_update_bits(data->regmap, data->regofs + ((id / 32) << 2), + BIT(id % 32), ~0); +} + +static int mtk_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct mtk_reset *data = container_of(rcdev, struct mtk_reset, rcdev); + + return regmap_update_bits(data->regmap, data->regofs + ((id / 32) << 2), + BIT(id % 32), 0); +} + +static int mtk_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + int ret; + + ret = mtk_reset_assert(rcdev, id); + if (ret) + return ret; + + return mtk_reset_deassert(rcdev, id); +} + +static struct reset_control_ops mtk_reset_ops = { + .assert = mtk_reset_assert, + .deassert = mtk_reset_deassert, + .reset = mtk_reset, +}; + +void mtk_register_reset_controller(struct device_node *np, + unsigned int num_regs, int regofs) +{ + struct mtk_reset *data; + int ret; + struct regmap *regmap; + + regmap = syscon_node_to_regmap(np); + if (IS_ERR(regmap)) { + pr_err("Cannot find regmap for %s: %ld\n", np->full_name, + PTR_ERR(regmap)); + return; + } + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return; + + data->regmap = regmap; + data->regofs = regofs; + data->rcdev.owner = THIS_MODULE; + data->rcdev.nr_resets = num_regs * 32; + data->rcdev.ops = &mtk_reset_ops; + data->rcdev.of_node = np; + + ret = reset_controller_register(&data->rcdev); + if (ret) { + pr_err("could not register reset controller: %d\n", ret); + kfree(data); + return; + } +} |