11802d0beSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-only
22655f51dSCatalin Marinas /*
32655f51dSCatalin Marinas *
42655f51dSCatalin Marinas * Copyright (C) 2012 ARM Limited
52655f51dSCatalin Marinas */
62655f51dSCatalin Marinas
7d08b8037SPawel Moll #include <linux/delay.h>
846c99ac6SGuenter Roeck #include <linux/notifier.h>
92655f51dSCatalin Marinas #include <linux/of.h>
102655f51dSCatalin Marinas #include <linux/of_device.h>
112655f51dSCatalin Marinas #include <linux/platform_device.h>
1246c99ac6SGuenter Roeck #include <linux/reboot.h>
132655f51dSCatalin Marinas #include <linux/stat.h>
142655f51dSCatalin Marinas #include <linux/vexpress.h>
152655f51dSCatalin Marinas
vexpress_reset_do(struct device * dev,const char * what)162655f51dSCatalin Marinas static void vexpress_reset_do(struct device *dev, const char *what)
172655f51dSCatalin Marinas {
182655f51dSCatalin Marinas int err = -ENOENT;
193b9334acSPawel Moll struct regmap *reg = dev_get_drvdata(dev);
202655f51dSCatalin Marinas
213b9334acSPawel Moll if (reg) {
223b9334acSPawel Moll err = regmap_write(reg, 0, 0);
23d08b8037SPawel Moll if (!err)
24d08b8037SPawel Moll mdelay(1000);
252655f51dSCatalin Marinas }
262655f51dSCatalin Marinas
272655f51dSCatalin Marinas dev_emerg(dev, "Unable to %s (%d)\n", what, err);
282655f51dSCatalin Marinas }
292655f51dSCatalin Marinas
302655f51dSCatalin Marinas static struct device *vexpress_power_off_device;
3109bebb1aSSudeep Holla static atomic_t vexpress_restart_nb_refcnt = ATOMIC_INIT(0);
322655f51dSCatalin Marinas
vexpress_power_off(void)3365deb782SCatalin Marinas static void vexpress_power_off(void)
342655f51dSCatalin Marinas {
352655f51dSCatalin Marinas vexpress_reset_do(vexpress_power_off_device, "power off");
362655f51dSCatalin Marinas }
372655f51dSCatalin Marinas
382655f51dSCatalin Marinas static struct device *vexpress_restart_device;
392655f51dSCatalin Marinas
vexpress_restart(struct notifier_block * this,unsigned long mode,void * cmd)4046c99ac6SGuenter Roeck static int vexpress_restart(struct notifier_block *this, unsigned long mode,
4146c99ac6SGuenter Roeck void *cmd)
422655f51dSCatalin Marinas {
432655f51dSCatalin Marinas vexpress_reset_do(vexpress_restart_device, "restart");
4446c99ac6SGuenter Roeck
4546c99ac6SGuenter Roeck return NOTIFY_DONE;
462655f51dSCatalin Marinas }
472655f51dSCatalin Marinas
4846c99ac6SGuenter Roeck static struct notifier_block vexpress_restart_nb = {
4946c99ac6SGuenter Roeck .notifier_call = vexpress_restart,
5046c99ac6SGuenter Roeck .priority = 128,
5146c99ac6SGuenter Roeck };
5246c99ac6SGuenter Roeck
vexpress_reset_active_show(struct device * dev,struct device_attribute * attr,char * buf)532655f51dSCatalin Marinas static ssize_t vexpress_reset_active_show(struct device *dev,
542655f51dSCatalin Marinas struct device_attribute *attr, char *buf)
552655f51dSCatalin Marinas {
562655f51dSCatalin Marinas return sprintf(buf, "%d\n", vexpress_restart_device == dev);
572655f51dSCatalin Marinas }
582655f51dSCatalin Marinas
vexpress_reset_active_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)592655f51dSCatalin Marinas static ssize_t vexpress_reset_active_store(struct device *dev,
602655f51dSCatalin Marinas struct device_attribute *attr, const char *buf, size_t count)
612655f51dSCatalin Marinas {
622655f51dSCatalin Marinas long value;
632655f51dSCatalin Marinas int err = kstrtol(buf, 0, &value);
642655f51dSCatalin Marinas
652655f51dSCatalin Marinas if (!err && value)
662655f51dSCatalin Marinas vexpress_restart_device = dev;
672655f51dSCatalin Marinas
682655f51dSCatalin Marinas return err ? err : count;
692655f51dSCatalin Marinas }
702655f51dSCatalin Marinas
710a14d280SBen Dooks static DEVICE_ATTR(active, S_IRUGO | S_IWUSR, vexpress_reset_active_show,
722655f51dSCatalin Marinas vexpress_reset_active_store);
732655f51dSCatalin Marinas
742655f51dSCatalin Marinas
752655f51dSCatalin Marinas enum vexpress_reset_func { FUNC_RESET, FUNC_SHUTDOWN, FUNC_REBOOT };
762655f51dSCatalin Marinas
778fb08855SFabian Frederick static const struct of_device_id vexpress_reset_of_match[] = {
782655f51dSCatalin Marinas {
792655f51dSCatalin Marinas .compatible = "arm,vexpress-reset",
802655f51dSCatalin Marinas .data = (void *)FUNC_RESET,
812655f51dSCatalin Marinas }, {
822655f51dSCatalin Marinas .compatible = "arm,vexpress-shutdown",
832655f51dSCatalin Marinas .data = (void *)FUNC_SHUTDOWN
842655f51dSCatalin Marinas }, {
852655f51dSCatalin Marinas .compatible = "arm,vexpress-reboot",
862655f51dSCatalin Marinas .data = (void *)FUNC_REBOOT
872655f51dSCatalin Marinas },
882655f51dSCatalin Marinas {}
892655f51dSCatalin Marinas };
902655f51dSCatalin Marinas
_vexpress_register_restart_handler(struct device * dev)9146c99ac6SGuenter Roeck static int _vexpress_register_restart_handler(struct device *dev)
9246c99ac6SGuenter Roeck {
9346c99ac6SGuenter Roeck int err;
9446c99ac6SGuenter Roeck
9546c99ac6SGuenter Roeck vexpress_restart_device = dev;
9609bebb1aSSudeep Holla if (atomic_inc_return(&vexpress_restart_nb_refcnt) == 1) {
9746c99ac6SGuenter Roeck err = register_restart_handler(&vexpress_restart_nb);
9846c99ac6SGuenter Roeck if (err) {
9946c99ac6SGuenter Roeck dev_err(dev, "cannot register restart handler (err=%d)\n", err);
10009bebb1aSSudeep Holla atomic_dec(&vexpress_restart_nb_refcnt);
10146c99ac6SGuenter Roeck return err;
10246c99ac6SGuenter Roeck }
10309bebb1aSSudeep Holla }
10446c99ac6SGuenter Roeck device_create_file(dev, &dev_attr_active);
10546c99ac6SGuenter Roeck
10646c99ac6SGuenter Roeck return 0;
10746c99ac6SGuenter Roeck }
10846c99ac6SGuenter Roeck
vexpress_reset_probe(struct platform_device * pdev)1092655f51dSCatalin Marinas static int vexpress_reset_probe(struct platform_device *pdev)
1102655f51dSCatalin Marinas {
1112655f51dSCatalin Marinas const struct of_device_id *match =
1122655f51dSCatalin Marinas of_match_device(vexpress_reset_of_match, &pdev->dev);
1133b9334acSPawel Moll struct regmap *regmap;
11446c99ac6SGuenter Roeck int ret = 0;
1152655f51dSCatalin Marinas
1168f961c0aSPawel Moll if (!match)
1178f961c0aSPawel Moll return -EINVAL;
1182655f51dSCatalin Marinas
1193b9334acSPawel Moll regmap = devm_regmap_init_vexpress_config(&pdev->dev);
1203b9334acSPawel Moll if (IS_ERR(regmap))
1213b9334acSPawel Moll return PTR_ERR(regmap);
1223b9334acSPawel Moll dev_set_drvdata(&pdev->dev, regmap);
123d08b8037SPawel Moll
124*4ec7b666SJustin Stitt switch ((uintptr_t)match->data) {
1252655f51dSCatalin Marinas case FUNC_SHUTDOWN:
1262655f51dSCatalin Marinas vexpress_power_off_device = &pdev->dev;
12765deb782SCatalin Marinas pm_power_off = vexpress_power_off;
1282655f51dSCatalin Marinas break;
1292655f51dSCatalin Marinas case FUNC_RESET:
1302655f51dSCatalin Marinas if (!vexpress_restart_device)
13146c99ac6SGuenter Roeck ret = _vexpress_register_restart_handler(&pdev->dev);
1322655f51dSCatalin Marinas break;
1332655f51dSCatalin Marinas case FUNC_REBOOT:
13446c99ac6SGuenter Roeck ret = _vexpress_register_restart_handler(&pdev->dev);
1352655f51dSCatalin Marinas break;
136091d0a3aSdongjian }
1372655f51dSCatalin Marinas
13846c99ac6SGuenter Roeck return ret;
1392655f51dSCatalin Marinas }
1402655f51dSCatalin Marinas
1412655f51dSCatalin Marinas static struct platform_driver vexpress_reset_driver = {
1422655f51dSCatalin Marinas .probe = vexpress_reset_probe,
1432655f51dSCatalin Marinas .driver = {
1442655f51dSCatalin Marinas .name = "vexpress-reset",
1452655f51dSCatalin Marinas .of_match_table = vexpress_reset_of_match,
14673174accSAnders Roxell .suppress_bind_attrs = true,
1472655f51dSCatalin Marinas },
1482655f51dSCatalin Marinas };
149a90d9904SAnders Roxell builtin_platform_driver(vexpress_reset_driver);
150