X-Git-Url: https://gerrit.opnfv.org/gerrit/gitweb?a=blobdiff_plain;f=kernel%2Fdrivers%2Fpower%2Freset%2Fvexpress-poweroff.c;fp=kernel%2Fdrivers%2Fpower%2Freset%2Fvexpress-poweroff.c;h=6a9bf7089373600120739f8f51829ba07344f8aa;hb=9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00;hp=0000000000000000000000000000000000000000;hpb=98260f3884f4a202f9ca5eabed40b1354c489b29;p=kvmfornfv.git diff --git a/kernel/drivers/power/reset/vexpress-poweroff.c b/kernel/drivers/power/reset/vexpress-poweroff.c new file mode 100644 index 000000000..6a9bf7089 --- /dev/null +++ b/kernel/drivers/power/reset/vexpress-poweroff.c @@ -0,0 +1,156 @@ +/* + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program 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. + * + * Copyright (C) 2012 ARM Limited + */ + +#include +#include +#include +#include +#include +#include +#include +#include + +static void vexpress_reset_do(struct device *dev, const char *what) +{ + int err = -ENOENT; + struct regmap *reg = dev_get_drvdata(dev); + + if (reg) { + err = regmap_write(reg, 0, 0); + if (!err) + mdelay(1000); + } + + dev_emerg(dev, "Unable to %s (%d)\n", what, err); +} + +static struct device *vexpress_power_off_device; + +static void vexpress_power_off(void) +{ + vexpress_reset_do(vexpress_power_off_device, "power off"); +} + +static struct device *vexpress_restart_device; + +static int vexpress_restart(struct notifier_block *this, unsigned long mode, + void *cmd) +{ + vexpress_reset_do(vexpress_restart_device, "restart"); + + return NOTIFY_DONE; +} + +static struct notifier_block vexpress_restart_nb = { + .notifier_call = vexpress_restart, + .priority = 128, +}; + +static ssize_t vexpress_reset_active_show(struct device *dev, + struct device_attribute *attr, char *buf) +{ + return sprintf(buf, "%d\n", vexpress_restart_device == dev); +} + +static ssize_t vexpress_reset_active_store(struct device *dev, + struct device_attribute *attr, const char *buf, size_t count) +{ + long value; + int err = kstrtol(buf, 0, &value); + + if (!err && value) + vexpress_restart_device = dev; + + return err ? err : count; +} + +DEVICE_ATTR(active, S_IRUGO | S_IWUSR, vexpress_reset_active_show, + vexpress_reset_active_store); + + +enum vexpress_reset_func { FUNC_RESET, FUNC_SHUTDOWN, FUNC_REBOOT }; + +static const struct of_device_id vexpress_reset_of_match[] = { + { + .compatible = "arm,vexpress-reset", + .data = (void *)FUNC_RESET, + }, { + .compatible = "arm,vexpress-shutdown", + .data = (void *)FUNC_SHUTDOWN + }, { + .compatible = "arm,vexpress-reboot", + .data = (void *)FUNC_REBOOT + }, + {} +}; + +static int _vexpress_register_restart_handler(struct device *dev) +{ + int err; + + vexpress_restart_device = dev; + err = register_restart_handler(&vexpress_restart_nb); + if (err) { + dev_err(dev, "cannot register restart handler (err=%d)\n", err); + return err; + } + device_create_file(dev, &dev_attr_active); + + return 0; +} + +static int vexpress_reset_probe(struct platform_device *pdev) +{ + const struct of_device_id *match = + of_match_device(vexpress_reset_of_match, &pdev->dev); + struct regmap *regmap; + int ret = 0; + + if (!match) + return -EINVAL; + + regmap = devm_regmap_init_vexpress_config(&pdev->dev); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + dev_set_drvdata(&pdev->dev, regmap); + + switch ((enum vexpress_reset_func)match->data) { + case FUNC_SHUTDOWN: + vexpress_power_off_device = &pdev->dev; + pm_power_off = vexpress_power_off; + break; + case FUNC_RESET: + if (!vexpress_restart_device) + ret = _vexpress_register_restart_handler(&pdev->dev); + break; + case FUNC_REBOOT: + ret = _vexpress_register_restart_handler(&pdev->dev); + break; + }; + + return ret; +} + +static struct platform_driver vexpress_reset_driver = { + .probe = vexpress_reset_probe, + .driver = { + .name = "vexpress-reset", + .of_match_table = vexpress_reset_of_match, + }, +}; + +static int __init vexpress_reset_init(void) +{ + return platform_driver_register(&vexpress_reset_driver); +} +device_initcall(vexpress_reset_init);