diff options
Diffstat (limited to 'drivers/reset')
| -rw-r--r-- | drivers/reset/Kconfig | 15 | ||||
| -rw-r--r-- | drivers/reset/Makefile | 5 | ||||
| -rw-r--r-- | drivers/reset/reset-uclass.c | 131 |
3 files changed, 151 insertions, 0 deletions
diff --git a/drivers/reset/Kconfig b/drivers/reset/Kconfig new file mode 100644 index 0000000..5c449a9 --- /dev/null +++ b/drivers/reset/Kconfig @@ -0,0 +1,15 @@ +menu "Reset Controller Support" + +config DM_RESET + bool "Enable reset controllers using Driver Model" + depends on DM && OF_CONTROL + help + Enable support for the reset controller driver class. Many hardware + modules are equipped with a reset signal, typically driven by some + reset controller hardware module within the chip. In U-Boot, reset + controller drivers allow control over these reset signals. In some + cases this API is applicable to chips outside the CPU as well, + although driving such reset isgnals using GPIOs may be more + appropriate in this case. + +endmenu diff --git a/drivers/reset/Makefile b/drivers/reset/Makefile new file mode 100644 index 0000000..508608e --- /dev/null +++ b/drivers/reset/Makefile @@ -0,0 +1,5 @@ +# Copyright (c) 2016, NVIDIA CORPORATION. +# +# SPDX-License-Identifier: GPL-2.0 + +obj-$(CONFIG_DM_RESET) += reset-uclass.o diff --git a/drivers/reset/reset-uclass.c b/drivers/reset/reset-uclass.c new file mode 100644 index 0000000..edaecfb --- /dev/null +++ b/drivers/reset/reset-uclass.c @@ -0,0 +1,131 @@ +/* + * Copyright (c) 2016, NVIDIA CORPORATION. + * + * SPDX-License-Identifier: GPL-2.0 + */ + +#include <common.h> +#include <dm.h> +#include <fdtdec.h> +#include <reset.h> +#include <reset-uclass.h> + +DECLARE_GLOBAL_DATA_PTR; + +static inline struct reset_ops *reset_dev_ops(struct udevice *dev) +{ + return (struct reset_ops *)dev->driver->ops; +} + +static int reset_of_xlate_default(struct reset_ctl *reset_ctl, + struct fdtdec_phandle_args *args) +{ + debug("%s(reset_ctl=%p)\n", __func__, reset_ctl); + + if (args->args_count != 1) { + debug("Invaild args_count: %d\n", args->args_count); + return -EINVAL; + } + + reset_ctl->id = args->args[0]; + + return 0; +} + +int reset_get_by_index(struct udevice *dev, int index, + struct reset_ctl *reset_ctl) +{ + struct fdtdec_phandle_args args; + int ret; + struct udevice *dev_reset; + struct reset_ops *ops; + + debug("%s(dev=%p, index=%d, reset_ctl=%p)\n", __func__, dev, index, + reset_ctl); + + ret = fdtdec_parse_phandle_with_args(gd->fdt_blob, dev->of_offset, + "resets", "#reset-cells", 0, + index, &args); + if (ret) { + debug("%s: fdtdec_parse_phandle_with_args failed: %d\n", + __func__, ret); + return ret; + } + + ret = uclass_get_device_by_of_offset(UCLASS_RESET, args.node, + &dev_reset); + if (ret) { + debug("%s: uclass_get_device_by_of_offset failed: %d\n", + __func__, ret); + return ret; + } + ops = reset_dev_ops(dev_reset); + + reset_ctl->dev = dev_reset; + if (ops->of_xlate) + ret = ops->of_xlate(reset_ctl, &args); + else + ret = reset_of_xlate_default(reset_ctl, &args); + if (ret) { + debug("of_xlate() failed: %d\n", ret); + return ret; + } + + ret = ops->request(reset_ctl); + if (ret) { + debug("ops->request() failed: %d\n", ret); + return ret; + } + + return 0; +} + +int reset_get_by_name(struct udevice *dev, const char *name, + struct reset_ctl *reset_ctl) +{ + int index; + + debug("%s(dev=%p, name=%s, reset_ctl=%p)\n", __func__, dev, name, + reset_ctl); + + index = fdt_find_string(gd->fdt_blob, dev->of_offset, "reset-names", + name); + if (index < 0) { + debug("fdt_find_string() failed: %d\n", index); + return index; + } + + return reset_get_by_index(dev, index, reset_ctl); +} + +int reset_free(struct reset_ctl *reset_ctl) +{ + struct reset_ops *ops = reset_dev_ops(reset_ctl->dev); + + debug("%s(reset_ctl=%p)\n", __func__, reset_ctl); + + return ops->free(reset_ctl); +} + +int reset_assert(struct reset_ctl *reset_ctl) +{ + struct reset_ops *ops = reset_dev_ops(reset_ctl->dev); + + debug("%s(reset_ctl=%p)\n", __func__, reset_ctl); + + return ops->rst_assert(reset_ctl); +} + +int reset_deassert(struct reset_ctl *reset_ctl) +{ + struct reset_ops *ops = reset_dev_ops(reset_ctl->dev); + + debug("%s(reset_ctl=%p)\n", __func__, reset_ctl); + + return ops->rst_deassert(reset_ctl); +} + +UCLASS_DRIVER(reset) = { + .id = UCLASS_RESET, + .name = "reset", +}; |