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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-20 08:15:23 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-09-20 08:15:23 -0700 |
| commit | bdab18633a302c82b5e5d5dbc4e38b0baf9c0837 (patch) | |
| tree | 0446500af9a76d4e8b2a72a0a41391ceede73a10 /drivers/power/reset/syscon-poweroff.c | |
| download | linux-stable-bdab18633a302c82b5e5d5dbc4e38b0baf9c0837.tar.gz linux-stable-bdab18633a302c82b5e5d5dbc4e38b0baf9c0837.zip | |
Merge tag 'locking-urgent-2026-09-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tipgrafted
Pull futex fix from Ingo Molnar:
- Also allocate a default private futex hash on vfork() as well, to
avoid races with (private) futex waiters (Peter Zijlstra)
* tag 'locking-urgent-2026-09-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Also allocate private hash on vfork()
Diffstat (limited to 'drivers/power/reset/syscon-poweroff.c')
| -rw-r--r-- | drivers/power/reset/syscon-poweroff.c | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/drivers/power/reset/syscon-poweroff.c b/drivers/power/reset/syscon-poweroff.c new file mode 100644 index 000000000..203936f4c --- /dev/null +++ b/drivers/power/reset/syscon-poweroff.c @@ -0,0 +1,98 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Generic Syscon Poweroff Driver + * + * Copyright (c) 2015, National Instruments Corp. + * Author: Moritz Fischer <moritz.fischer@ettus.com> + */ + +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/notifier.h> +#include <linux/mfd/syscon.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/pm.h> +#include <linux/reboot.h> +#include <linux/regmap.h> + +struct syscon_poweroff_data { + struct regmap *map; + u32 offset; + u32 value; + u32 mask; +}; + +static int syscon_poweroff(struct sys_off_data *off_data) +{ + struct syscon_poweroff_data *data = off_data->cb_data; + + /* Issue the poweroff */ + regmap_update_bits(data->map, data->offset, data->mask, data->value); + + mdelay(1000); + + pr_emerg("Unable to poweroff system\n"); + + return NOTIFY_DONE; +} + +static int syscon_poweroff_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct syscon_poweroff_data *data; + int mask_err, value_err; + + data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + data->map = syscon_regmap_lookup_by_phandle(dev->of_node, "regmap"); + if (IS_ERR(data->map)) { + data->map = syscon_node_to_regmap(dev->parent->of_node); + if (IS_ERR(data->map)) { + dev_err(dev, "unable to get syscon"); + return PTR_ERR(data->map); + } + } + + if (of_property_read_u32(dev->of_node, "offset", &data->offset)) { + dev_err(dev, "unable to read 'offset'"); + return -EINVAL; + } + + value_err = of_property_read_u32(dev->of_node, "value", &data->value); + mask_err = of_property_read_u32(dev->of_node, "mask", &data->mask); + if (value_err && mask_err) { + dev_err(dev, "unable to read 'value' and 'mask'"); + return -EINVAL; + } + + if (value_err) { + /* support old binding */ + data->value = data->mask; + data->mask = 0xFFFFFFFF; + } else if (mask_err) { + /* support value without mask*/ + data->mask = 0xFFFFFFFF; + } + + return devm_register_sys_off_handler(&pdev->dev, + SYS_OFF_MODE_POWER_OFF, + SYS_OFF_PRIO_DEFAULT, + syscon_poweroff, data); +} + +static const struct of_device_id syscon_poweroff_of_match[] = { + { .compatible = "syscon-poweroff" }, + {} +}; + +static struct platform_driver syscon_poweroff_driver = { + .probe = syscon_poweroff_probe, + .driver = { + .name = "syscon-poweroff", + .of_match_table = syscon_poweroff_of_match, + }, +}; +builtin_platform_driver(syscon_poweroff_driver); |
