Add System reset controller driver for PLX Technology OXNAS SoC Family. CC: Ma Haijun <mahaij...@gmail.com> Signed-off-by: Neil Armstrong <narmstr...@baylibre.com> --- drivers/reset/Kconfig | 4 ++ drivers/reset/Makefile | 1 + drivers/reset/reset-oxnas.c | 149 ++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 154 insertions(+) create mode 100644 drivers/reset/reset-oxnas.c
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig index df37212..f0ea63b 100644 --- a/drivers/reset/Kconfig +++ b/drivers/reset/Kconfig @@ -12,5 +12,9 @@ menuconfig RESET_CONTROLLER If unsure, say no. +config RESET_OXNAS + bool + select MFD_SYSCON + source "drivers/reset/sti/Kconfig" source "drivers/reset/hisilicon/Kconfig" diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile index 4d7178e..97e04c5 100644 --- a/drivers/reset/Makefile +++ b/drivers/reset/Makefile @@ -7,3 +7,4 @@ obj-$(CONFIG_ARCH_STI) += sti/ obj-$(CONFIG_ARCH_HISI) += hisilicon/ obj-$(CONFIG_ARCH_ZYNQ) += reset-zynq.o obj-$(CONFIG_ATH79) += reset-ath79.o +obj-$(CONFIG_RESET_OXNAS) += reset-oxnas.o diff --git a/drivers/reset/reset-oxnas.c b/drivers/reset/reset-oxnas.c new file mode 100644 index 0000000..d0ab670 --- /dev/null +++ b/drivers/reset/reset-oxnas.c @@ -0,0 +1,149 @@ +/* + * drivers/reset/reset-oxnas.c + * + * Copyright (C) 2016 Neil Armstrong <narmstr...@baylibre.com> + * Copyright (C) 2014 Ma Haijun <mahaij...@gmail.com> + * Copyright (C) 2009 Oxford Semiconductor Ltd + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reset-controller.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/types.h> +#include <linux/regmap.h> +#include <linux/mfd/syscon.h> + +/* Regmap offsets */ +#define RST_SET_REGOFFSET 0x34 +#define RST_CLR_REGOFFSET 0x38 + +struct oxnas_reset { + struct regmap *regmap; + struct reset_controller_dev rcdev; +}; + +static int oxnas_reset_reset(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct oxnas_reset *data = + container_of(rcdev, struct oxnas_reset, rcdev); + + regmap_write(data->regmap, RST_SET_REGOFFSET, BIT(id)); + msleep(50); + regmap_write(data->regmap, RST_CLR_REGOFFSET, BIT(id)); + + return 0; +} + +static int oxnas_reset_assert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct oxnas_reset *data = + container_of(rcdev, struct oxnas_reset, rcdev); + + regmap_write(data->regmap, RST_SET_REGOFFSET, BIT(id)); + + return 0; +} + +static int oxnas_reset_deassert(struct reset_controller_dev *rcdev, + unsigned long id) +{ + struct oxnas_reset *data = + container_of(rcdev, struct oxnas_reset, rcdev); + + regmap_write(data->regmap, RST_CLR_REGOFFSET, BIT(id)); + + return 0; +} + +static struct reset_control_ops oxnas_reset_ops = { + .reset = oxnas_reset_reset, + .assert = oxnas_reset_assert, + .deassert = oxnas_reset_deassert, +}; + +static const struct of_device_id oxnas_reset_dt_ids[] = { + { .compatible = "plxtech,nas782x-reset", }, + { /* sentinel */ }, +}; +MODULE_DEVICE_TABLE(of, oxnas_reset_dt_ids); + +static int oxnas_reset_probe(struct platform_device *pdev) +{ + struct oxnas_reset *data; + struct device *parent; + + parent = pdev->dev.parent; + if (!parent) { + dev_err(&pdev->dev, "no parent\n"); + return -ENODEV; + } + + data = devm_kzalloc(&pdev->dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->regmap = syscon_node_to_regmap(parent->of_node); + if (IS_ERR(data->regmap)) { + dev_err(&pdev->dev, "failed to get parent regmap\n"); + return -ENODEV; + } + + data->rcdev.owner = THIS_MODULE; + data->rcdev.nr_resets = 32; + data->rcdev.ops = &oxnas_reset_ops; + data->rcdev.of_node = pdev->dev.of_node; + reset_controller_register(&data->rcdev); + + platform_set_drvdata(pdev, data); + + return 0; +} + +static int oxnas_reset_remove(struct platform_device *pdev) +{ + struct oxnas_reset *data = platform_get_drvdata(pdev); + + reset_controller_unregister(&data->rcdev); + + return 0; +} + +static struct platform_driver oxnas_reset_driver = { + .probe = oxnas_reset_probe, + .remove = oxnas_reset_remove, + .driver = { + .name = "oxnas-reset", + .owner = THIS_MODULE, + .of_match_table = oxnas_reset_dt_ids, + }, +}; + +static int __init oxnas_reset_init(void) +{ + return platform_driver_probe(&oxnas_reset_driver, + oxnas_reset_probe); +} + +/* + * Reset controller does not support probe deferral, so it has to be + * initialized before any user, in particular, PCIE uses subsys_initcall. + */ +arch_initcall(oxnas_reset_init); -- 1.9.1