This patch adds the platform driver for the Amlogic Meson GXBB Reset Controller.
Signed-off-by: Neil Armstrong <[email protected]> --- drivers/reset/Kconfig | 6 ++ drivers/reset/Makefile | 1 + drivers/reset/reset-meson-gxbb.c | 129 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 136 insertions(+) create mode 100644 drivers/reset/reset-meson-gxbb.c diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index df37212..4ac5c4d 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -12,5 +12,11 @@ menuconfig RESET_CONTROLLER If unsure, say no. +config MESON_GXBB_RESET + tristate "Amlogic Meson GXBB Reset Driver" + depends on (ARCH_MESON && RESET_CONTROLLER) + help + Build the Amlogic Meson GxBB reset driver. + source "drivers/reset/sti/Kconfig" source "drivers/reset/hisilicon/Kconfig" diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index a1fc8ed..5ff83a1 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -3,6 +3,7 @@ obj-$(CONFIG_ARCH_LPC18XX) += reset-lpc18xx.o obj-$(CONFIG_ARCH_SOCFPGA) += reset-socfpga.o obj-$(CONFIG_ARCH_BERLIN) += reset-berlin.o obj-$(CONFIG_MACH_PISTACHIO) += reset-pistachio.o +obj-$(CONFIG_MESON_GXBB_RESET) += reset-meson-gxbb.o obj-$(CONFIG_ARCH_SUNXI) += reset-sunxi.o obj-$(CONFIG_ARCH_STI) += sti/ obj-$(CONFIG_ARCH_HISI) += hisilicon/ diff --git a/drivers/reset/reset-meson-gxbb.c b/drivers/reset/reset-meson-gxbb.c new file mode 100644 index 0000000..e96691b --- /dev/null +++ b/drivers/reset/reset-meson-gxbb.c @@ -0,0 +1,129 @@ +/* + * Copyright (c) 2016 BayLibre, SAS. + * Author: Neil Armstrong <[email protected]> + * + * This file is dual-licensed: you can use it either under the terms + * of the GPL or the X11 license, at your option. Note that this dual + * licensing only applies to this file, and not this project as a + * whole. + * + * a) This library 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. + * + * This library 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. + * + * Or, alternatively, + * + * b) Permission is hereby granted, free of charge, to any person + * obtaining a copy of this software and associated documentation + * files (the "Software"), to deal in the Software without + * restriction, including without limitation the rights to use, + * copy, modify, merge, publish, distribute, sublicense, and/or + * sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following + * conditions: + * + * The above copyright notice and this permission notice shall be + * included in all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES + * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT + * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR + * OTHER DEALINGS IN THE SOFTWARE. + */ +#include <linux/err.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> +#include <linux/types.h> + +#define REG_COUNT 8 +#define BITS_PER_REG 32 + +struct meson_gxbb_reset { + void __iomem *reg_base; + struct reset_controller_dev rcdev; +}; + +static int meson_gxbb_reset_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct meson_gxbb_reset *data = + container_of(rcdev, struct meson_gxbb_reset, rcdev); + unsigned int bank = id / BITS_PER_REG; + unsigned int offset = id % BITS_PER_REG; + void __iomem *reg_addr = data->reg_base + (bank << 2); + + if (bank >= REG_COUNT) + return -EINVAL; + + writel(BIT(offset), reg_addr); + + return 0; +} + +static const struct reset_control_ops meson_gxbb_reset_ops = { + .reset = meson_gxbb_reset_reset, +}; + +static const struct of_device_id meson_gxbb_reset_dt_ids[] = { + { .compatible = "amlogic,meson-gxbb-reset", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, meson_gxbb_reset_dt_ids); + +static int meson_gxbb_reset_probe(struct platform_device *pdev) +{ + struct meson_gxbb_reset *data; + struct resource *res; + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + data->reg_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(data->reg_base)) + return PTR_ERR(data->reg_base); + + platform_set_drvdata(pdev, data); + + data->rcdev.owner = THIS_MODULE; + data->rcdev.nr_resets = REG_COUNT * BITS_PER_REG; + data->rcdev.ops = &meson_gxbb_reset_ops; + data->rcdev.of_node = pdev->dev.of_node; + + return reset_controller_register(&data->rcdev); +} + +static int meson_gxbb_reset_remove(struct platform_device *pdev) +{ + struct meson_gxbb_reset *data = platform_get_drvdata(pdev); + + reset_controller_unregister(&data->rcdev); + + return 0; +} + +static struct platform_driver meson_gxbb_reset_driver = { + .probe = meson_gxbb_reset_probe, + .remove = meson_gxbb_reset_remove, + .driver = { + .name = "meson_gxbb_reset", + .of_match_table = meson_gxbb_reset_dt_ids, + }, +}; + +module_platform_driver(meson_gxbb_reset_driver); -- 2.7.0
