diff options
author | Han Nandor <nandor.han@vaisala.com> | 2019-05-15 10:47:14 +0000 |
---|---|---|
committer | Sebastian Reichel <sre@kernel.org> | 2019-06-25 23:58:40 +0200 |
commit | 7a78a7f7695bf9ef9cef3c06fbc5fa4573fd0eef (patch) | |
tree | fe96dd089b859b37ea9b83cdea8b4dc493a06537 /drivers/power/reset | |
parent | cba155e50a117465b64e197e197aedc18770c4cd (diff) | |
download | linux-7a78a7f7695bf9ef9cef3c06fbc5fa4573fd0eef.tar.bz2 |
power: reset: nvmem-reboot-mode: use NVMEM as reboot mode write interface
Add a new reboot mode write interface that is using an NVMEM cell
to store the reboot mode magic.
Signed-off-by: Nandor Han <nandor.han@vaisala.com>
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Diffstat (limited to 'drivers/power/reset')
-rw-r--r-- | drivers/power/reset/Kconfig | 9 | ||||
-rw-r--r-- | drivers/power/reset/Makefile | 1 | ||||
-rw-r--r-- | drivers/power/reset/nvmem-reboot-mode.c | 76 |
3 files changed, 86 insertions, 0 deletions
diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index 6533aa560aa1..bb4a4e854f96 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -245,5 +245,14 @@ config POWER_RESET_SC27XX PMICs includes the SC2720, SC2721, SC2723, SC2730 and SC2731 chips. +config NVMEM_REBOOT_MODE + tristate "Generic NVMEM reboot mode driver" + select REBOOT_MODE + help + Say y here will enable reboot mode driver. This will + get reboot mode arguments and store it in a NVMEM cell, + then the bootloader can read it and take different + action according to the mode. + endif diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index 0aebee954ac1..85da3198e4e0 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -29,3 +29,4 @@ obj-$(CONFIG_POWER_RESET_ZX) += zx-reboot.o obj-$(CONFIG_REBOOT_MODE) += reboot-mode.o obj-$(CONFIG_SYSCON_REBOOT_MODE) += syscon-reboot-mode.o obj-$(CONFIG_POWER_RESET_SC27XX) += sc27xx-poweroff.o +obj-$(CONFIG_NVMEM_REBOOT_MODE) += nvmem-reboot-mode.o diff --git a/drivers/power/reset/nvmem-reboot-mode.c b/drivers/power/reset/nvmem-reboot-mode.c new file mode 100644 index 000000000000..e229308d43e2 --- /dev/null +++ b/drivers/power/reset/nvmem-reboot-mode.c @@ -0,0 +1,76 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (c) Vaisala Oyj. All rights reserved. + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/of.h> +#include <linux/nvmem-consumer.h> +#include <linux/platform_device.h> +#include <linux/reboot-mode.h> + +struct nvmem_reboot_mode { + struct reboot_mode_driver reboot; + struct nvmem_cell *cell; +}; + +static int nvmem_reboot_mode_write(struct reboot_mode_driver *reboot, + unsigned int magic) +{ + int ret; + struct nvmem_reboot_mode *nvmem_rbm; + + nvmem_rbm = container_of(reboot, struct nvmem_reboot_mode, reboot); + + ret = nvmem_cell_write(nvmem_rbm->cell, &magic, sizeof(magic)); + if (ret < 0) + dev_err(reboot->dev, "update reboot mode bits failed\n"); + + return ret; +} + +static int nvmem_reboot_mode_probe(struct platform_device *pdev) +{ + int ret; + struct nvmem_reboot_mode *nvmem_rbm; + + nvmem_rbm = devm_kzalloc(&pdev->dev, sizeof(*nvmem_rbm), GFP_KERNEL); + if (!nvmem_rbm) + return -ENOMEM; + + nvmem_rbm->reboot.dev = &pdev->dev; + nvmem_rbm->reboot.write = nvmem_reboot_mode_write; + + nvmem_rbm->cell = devm_nvmem_cell_get(&pdev->dev, "reboot-mode"); + if (IS_ERR(nvmem_rbm->cell)) { + dev_err(&pdev->dev, "failed to get the nvmem cell reboot-mode\n"); + return PTR_ERR(nvmem_rbm->cell); + } + + ret = devm_reboot_mode_register(&pdev->dev, &nvmem_rbm->reboot); + if (ret) + dev_err(&pdev->dev, "can't register reboot mode\n"); + + return ret; +} + +static const struct of_device_id nvmem_reboot_mode_of_match[] = { + { .compatible = "nvmem-reboot-mode" }, + {} +}; +MODULE_DEVICE_TABLE(of, nvmem_reboot_mode_of_match); + +static struct platform_driver nvmem_reboot_mode_driver = { + .probe = nvmem_reboot_mode_probe, + .driver = { + .name = "nvmem-reboot-mode", + .of_match_table = nvmem_reboot_mode_of_match, + }, +}; +module_platform_driver(nvmem_reboot_mode_driver); + +MODULE_AUTHOR("Nandor Han <nandor.han@vaisala.com>"); +MODULE_DESCRIPTION("NVMEM reboot mode driver"); +MODULE_LICENSE("GPL"); |