Merge tag 'ib-mfd-i2c-reboot-v6.7' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd into i2c/for-mergewindow

Immutable branch between MFD, I2C and Reboot due for the v6.7 merge window

Author: wsakernel

drivers/i2c/i2c-core.h

@@ -29,7 +29,7 @@ int i2c_dev_irq_from_resources(const struct resource *resources,
  */
 static inline bool i2c_in_atomic_xfer_mode(void)
 {
-	return system_state > SYSTEM_RUNNING && irqs_disabled();
+	return system_state > SYSTEM_RUNNING && !preemptible();
 }
 
 static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)

drivers/mfd/tps6586x.c

@@ -22,13 +22,15 @@
 #include <linux/err.h>
 #include <linux/i2c.h>
 #include <linux/platform_device.h>
+#include <linux/reboot.h>
 #include <linux/regmap.h>
 #include <linux/of.h>
 
 #include <linux/mfd/core.h>
 #include <linux/mfd/tps6586x.h>
 
 #define TPS6586X_SUPPLYENE	0x14
+#define SOFT_RST_BIT		BIT(0)
 #define EXITSLREQ_BIT		BIT(1)
 #define SLEEP_MODE_BIT		BIT(3)
 
@@ -457,13 +459,34 @@ static const struct regmap_config tps6586x_regmap_config = {
 	.cache_type = REGCACHE_RBTREE,
 };
 
-static struct device *tps6586x_dev;
-static void tps6586x_power_off(void)
+static int tps6586x_power_off_handler(struct sys_off_data *data)
 {
-	if (tps6586x_clr_bits(tps6586x_dev, TPS6586X_SUPPLYENE, EXITSLREQ_BIT))
-		return;
+	int ret;
+
+	/* Put the PMIC into sleep state. This takes at least 20ms. */
+	ret = tps6586x_clr_bits(data->dev, TPS6586X_SUPPLYENE, EXITSLREQ_BIT);
+	if (ret)
+		return notifier_from_errno(ret);
+
+	ret = tps6586x_set_bits(data->dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
+	if (ret)
+		return notifier_from_errno(ret);
+
+	mdelay(50);
+	return notifier_from_errno(-ETIME);
+}
+
+static int tps6586x_restart_handler(struct sys_off_data *data)
+{
+	int ret;
+
+	/* Put the PMIC into hard reboot state. This takes at least 20ms. */
+	ret = tps6586x_set_bits(data->dev, TPS6586X_SUPPLYENE, SOFT_RST_BIT);
+	if (ret)
+		return notifier_from_errno(ret);
 
-	tps6586x_set_bits(tps6586x_dev, TPS6586X_SUPPLYENE, SLEEP_MODE_BIT);
+	mdelay(50);
+	return notifier_from_errno(-ETIME);
 }
 
 static void tps6586x_print_version(struct i2c_client *client, int version)
@@ -559,9 +582,20 @@ static int tps6586x_i2c_probe(struct i2c_client *client)
 		goto err_add_devs;
 	}
 
-	if (pdata->pm_off && !pm_power_off) {
-		tps6586x_dev = &client->dev;
-		pm_power_off = tps6586x_power_off;
+	if (pdata->pm_off) {
+		ret = devm_register_power_off_handler(&client->dev, &tps6586x_power_off_handler,
+						      NULL);
+		if (ret) {
+			dev_err(&client->dev, "register power off handler failed: %d\n", ret);
+			goto err_add_devs;
+		}
+
+		ret = devm_register_restart_handler(&client->dev, &tps6586x_restart_handler,
+						    NULL);
+		if (ret) {
+			dev_err(&client->dev, "register restart handler failed: %d\n", ret);
+			goto err_add_devs;
+		}
 	}
 
 	return 0;

include/linux/reboot.h

@@ -129,11 +129,14 @@ enum sys_off_mode {
  * @cb_data: User's callback data.
  * @cmd: Command string. Currently used only by the sys-off restart mode,
  *       NULL otherwise.
+ * @dev: Device of the sys-off handler. Only if known (devm_register_*),
+ *       NULL otherwise.
  */
 struct sys_off_data {
 	int mode;
 	void *cb_data;
 	const char *cmd;
+	struct device *dev;
 };
 
 struct sys_off_handler *

kernel/reboot.c

@@ -55,6 +55,7 @@ struct sys_off_handler {
 	enum sys_off_mode mode;
 	bool blocking;
 	void *list;
+	struct device *dev;
 };
 
 /*
@@ -74,6 +75,7 @@ void __weak (*pm_power_off)(void);
 void emergency_restart(void)
 {
 	kmsg_dump(KMSG_DUMP_EMERG);
+	system_state = SYSTEM_RESTART;
 	machine_emergency_restart();
 }
 EXPORT_SYMBOL_GPL(emergency_restart);
@@ -323,6 +325,7 @@ static int sys_off_notify(struct notifier_block *nb,
 	data.cb_data = handler->cb_data;
 	data.mode = mode;
 	data.cmd = cmd;
+	data.dev = handler->dev;
 
 	return handler->sys_off_cb(&data);
 }
@@ -510,6 +513,7 @@ int devm_register_sys_off_handler(struct device *dev,
 	handler = register_sys_off_handler(mode, priority, callback, cb_data);
 	if (IS_ERR(handler))
 		return PTR_ERR(handler);
+	handler->dev = dev;
 
 	return devm_add_action_or_reset(dev, devm_unregister_sys_off_handler,
 					handler);