Merge tag 'chrome-platform-v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux

Pull chrome-platform updates from Tzung-Bi Shih:
 "Improvements:

   - Use named initializers for struct i2c_device_id

  Fixes:

   - Fix a probe race between cros_ec_sensorhub and cros_ec_sysfs

   - Check for the presence of ACPI_COMPANION() for drivers converted
     from acpi_driver to platform_driver to avoid issues where
     device_match_driver_override() might forcibly match the driver to
     the device

   - Fix a possible UAF in cros_ec_chardev

   - Prevent build for big-endian systems as CHROME_PLATFORMS drivers
     are only running and testing under little-endian systems

  Cleanups:

   - Drop some redundant bits in cros_kbd_led_backlight and Kconfig"

* tag 'chrome-platform-v7.2' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux:
  platform/chrome: Prevent build for big-endian systems
  platform/chrome: Remove superfluous dependencies from CROS_EC
  platform/chrome: cros_ec_chardev: Introduce rwsem for protecting ec_dev
  platform/chrome: cros_ec_chardev: Add event relayer
  platform/chrome: cros_ec_chardev: Move data to chardev_pdata
  platform/chrome: cros_ec_chardev: Introduce chardev_data
  platform/chrome: Use named initializers for struct i2c_device_id
  platform/chrome: wilco_ec: event: Check ACPI_COMPANION()
  platform/chrome: chromeos_tbmc: Check ACPI_COMPANION()
  platform/chrome: chromeos_privacy_screen: Check ACPI_COMPANION()
  platform/chrome: cros_kbd_led_backlight: Drop CONFIG_MFD_CROS_EC_DEV ifdeffery
  platform/chrome: cros_kbd_led_backlight: Pass keyboard_led as parameter
  platform/chrome: cros_kbd_led_backlight: Drop max_brightness from driver data
  platform/chrome: Resolve kb_wake_angle visibility race

drivers/platform/chrome/Kconfig

@@ -6,6 +6,7 @@
 menuconfig CHROME_PLATFORMS
 	bool "Platform support for Chrome hardware"
 	depends on X86 || ARM || ARM64 || COMPILE_TEST
+	depends on !CPU_BIG_ENDIAN || COMPILE_TEST
 	help
 	  Say Y here to get to see options for platform support for
 	  various Chromebooks and Chromeboxes. This option alone does
@@ -75,7 +76,6 @@ config CHROMEOS_OF_HW_PROBER
 config CROS_EC
 	tristate "ChromeOS Embedded Controller"
 	select CROS_EC_PROTO
-	depends on X86 || ARM || ARM64 || COMPILE_TEST
 	help
 	  If you say Y here you get support for the ChromeOS Embedded
 	  Controller (EC) providing keyboard, battery and power services.

drivers/platform/chrome/chromeos_privacy_screen.c

@@ -104,6 +104,9 @@ static const struct drm_privacy_screen_ops chromeos_privacy_screen_ops = {
 
 static int chromeos_privacy_screen_probe(struct platform_device *pdev)
 {
+	if (!ACPI_COMPANION(&pdev->dev))
+		return -ENODEV;
+
 	struct drm_privacy_screen *drm_privacy_screen =
 		drm_privacy_screen_register(&pdev->dev,
 					    &chromeos_privacy_screen_ops,

drivers/platform/chrome/chromeos_tbmc.c

@@ -69,9 +69,13 @@ static int chromeos_tbmc_probe(struct platform_device *pdev)
 {
 	struct input_dev *idev;
 	struct device *dev = &pdev->dev;
-	struct acpi_device *adev = ACPI_COMPANION(dev);
+	struct acpi_device *adev;
 	int ret;
 
+	adev = ACPI_COMPANION(dev);
+	if (!adev)
+		return -ENODEV;
+
 	idev = devm_input_allocate_device(dev);
 	if (!idev)
 		return -ENOMEM;

drivers/platform/chrome/cros_ec_chardev.c

@@ -13,6 +13,7 @@
 #include <linux/init.h>
 #include <linux/device.h>
 #include <linux/fs.h>
+#include <linux/kref.h>
 #include <linux/miscdevice.h>
 #include <linux/mod_devicetable.h>
 #include <linux/module.h>
@@ -22,6 +23,7 @@
 #include <linux/platform_data/cros_ec_proto.h>
 #include <linux/platform_device.h>
 #include <linux/poll.h>
+#include <linux/rwsem.h>
 #include <linux/slab.h>
 #include <linux/types.h>
 #include <linux/uaccess.h>
@@ -31,14 +33,44 @@
 /* Arbitrary bounded size for the event queue */
 #define CROS_MAX_EVENT_LEN	PAGE_SIZE
 
-struct chardev_priv {
+/*
+ * Platform device driver data.
+ */
+struct chardev_pdata {
+	struct miscdevice misc;
+	struct kref kref;
+	struct rw_semaphore ec_dev_sem;
 	struct cros_ec_device *ec_dev;
+	u16 cmd_offset;
+	struct blocking_notifier_head subscribers;
+	struct notifier_block relay;
+};
+
+static void chardev_pdata_release(struct kref *kref)
+{
+	struct chardev_pdata *pdata = container_of(kref, typeof(*pdata), kref);
+
+	kfree(pdata);
+}
+
+static int cros_ec_chardev_relay_event(struct notifier_block *nb,
+				       unsigned long queued_during_suspend,
+				       void *_notify)
+{
+	struct chardev_pdata *pdata = container_of(nb, typeof(*pdata), relay);
+
+	blocking_notifier_call_chain(&pdata->subscribers, queued_during_suspend,
+				     _notify);
+	return NOTIFY_OK;
+}
+
+struct chardev_priv {
 	struct notifier_block notifier;
 	wait_queue_head_t wait_event;
 	unsigned long event_mask;
 	struct list_head events;
 	size_t event_len;
-	u16 cmd_offset;
+	struct chardev_pdata *pdata;
 };
 
 struct ec_event {
@@ -61,10 +93,10 @@ static int ec_get_version(struct chardev_priv *priv, char *str, int maxlen)
 	if (!msg)
 		return -ENOMEM;
 
-	msg->command = EC_CMD_GET_VERSION + priv->cmd_offset;
+	msg->command = EC_CMD_GET_VERSION + priv->pdata->cmd_offset;
 	msg->insize = sizeof(*resp);
 
-	ret = cros_ec_cmd_xfer_status(priv->ec_dev, msg);
+	ret = cros_ec_cmd_xfer_status(priv->pdata->ec_dev, msg);
 	if (ret < 0) {
 		snprintf(str, maxlen,
 			 "Unknown EC version, returned error: %d\n",
@@ -92,10 +124,18 @@ static int cros_ec_chardev_mkbp_event(struct notifier_block *nb,
 {
 	struct chardev_priv *priv = container_of(nb, struct chardev_priv,
 						 notifier);
-	struct cros_ec_device *ec_dev = priv->ec_dev;
+	struct cros_ec_device *ec_dev;
 	struct ec_event *event;
-	unsigned long event_bit = 1 << ec_dev->event_data.event_type;
-	int total_size = sizeof(*event) + ec_dev->event_size;
+	unsigned long event_bit;
+	int total_size;
+
+	guard(rwsem_read)(&priv->pdata->ec_dev_sem);
+	if (!priv->pdata->ec_dev)
+		return NOTIFY_DONE;
+	ec_dev = priv->pdata->ec_dev;
+
+	event_bit = 1 << ec_dev->event_data.event_type;
+	total_size = sizeof(*event) + ec_dev->event_size;
 
 	if (!(event_bit & priv->event_mask) ||
 	    (priv->event_len + total_size) > CROS_MAX_EVENT_LEN)
@@ -157,8 +197,7 @@ static struct ec_event *cros_ec_chardev_fetch_event(struct chardev_priv *priv,
 static int cros_ec_chardev_open(struct inode *inode, struct file *filp)
 {
 	struct miscdevice *mdev = filp->private_data;
-	struct cros_ec_dev *ec = dev_get_drvdata(mdev->parent);
-	struct cros_ec_device *ec_dev = ec->ec_dev;
+	struct chardev_pdata *pdata = container_of(mdev, typeof(*pdata), misc);
 	struct chardev_priv *priv;
 	int ret;
 
@@ -166,18 +205,20 @@ static int cros_ec_chardev_open(struct inode *inode, struct file *filp)
 	if (!priv)
 		return -ENOMEM;
 
-	priv->ec_dev = ec_dev;
-	priv->cmd_offset = ec->cmd_offset;
+	priv->pdata = pdata;
+	kref_get(&pdata->kref);
 	filp->private_data = priv;
 	INIT_LIST_HEAD(&priv->events);
 	init_waitqueue_head(&priv->wait_event);
 	nonseekable_open(inode, filp);
 
 	priv->notifier.notifier_call = cros_ec_chardev_mkbp_event;
-	ret = blocking_notifier_chain_register(&ec_dev->event_notifier,
+	ret = blocking_notifier_chain_register(&pdata->subscribers,
 					       &priv->notifier);
 	if (ret) {
-		dev_err(ec_dev->dev, "failed to register event notifier\n");
+		dev_err(pdata->ec_dev->dev,
+			"failed to register event notifier\n");
+		kref_put(&priv->pdata->kref, chardev_pdata_release);
 		kfree(priv);
 	}
 
@@ -188,6 +229,10 @@ static __poll_t cros_ec_chardev_poll(struct file *filp, poll_table *wait)
 {
 	struct chardev_priv *priv = filp->private_data;
 
+	guard(rwsem_read)(&priv->pdata->ec_dev_sem);
+	if (!priv->pdata->ec_dev)
+		return EPOLLHUP;
+
 	poll_wait(filp, &priv->wait_event, wait);
 
 	if (list_empty(&priv->events))
@@ -205,6 +250,10 @@ static ssize_t cros_ec_chardev_read(struct file *filp, char __user *buffer,
 	size_t count;
 	int ret;
 
+	guard(rwsem_read)(&priv->pdata->ec_dev_sem);
+	if (!priv->pdata->ec_dev)
+		return -ENODEV;
+
 	if (priv->event_mask) { /* queued MKBP event */
 		struct ec_event *event;
 
@@ -251,11 +300,11 @@ static ssize_t cros_ec_chardev_read(struct file *filp, char __user *buffer,
 static int cros_ec_chardev_release(struct inode *inode, struct file *filp)
 {
 	struct chardev_priv *priv = filp->private_data;
-	struct cros_ec_device *ec_dev = priv->ec_dev;
 	struct ec_event *event, *e;
 
-	blocking_notifier_chain_unregister(&ec_dev->event_notifier,
+	blocking_notifier_chain_unregister(&priv->pdata->subscribers,
 					   &priv->notifier);
+	kref_put(&priv->pdata->kref, chardev_pdata_release);
 
 	list_for_each_entry_safe(event, e, &priv->events, node) {
 		list_del(&event->node);
@@ -298,8 +347,8 @@ static long cros_ec_chardev_ioctl_xcmd(struct chardev_priv *priv, void __user *a
 		goto exit;
 	}
 
-	s_cmd->command += priv->cmd_offset;
-	ret = cros_ec_cmd_xfer(priv->ec_dev, s_cmd);
+	s_cmd->command += priv->pdata->cmd_offset;
+	ret = cros_ec_cmd_xfer(priv->pdata->ec_dev, s_cmd);
 	/* Only copy data to userland if data was received. */
 	if (ret < 0)
 		goto exit;
@@ -313,7 +362,7 @@ static long cros_ec_chardev_ioctl_xcmd(struct chardev_priv *priv, void __user *a
 
 static long cros_ec_chardev_ioctl_readmem(struct chardev_priv *priv, void __user *arg)
 {
-	struct cros_ec_device *ec_dev = priv->ec_dev;
+	struct cros_ec_device *ec_dev = priv->pdata->ec_dev;
 	struct cros_ec_readmem s_mem = { };
 	long num;
 
@@ -343,6 +392,10 @@ static long cros_ec_chardev_ioctl(struct file *filp, unsigned int cmd,
 {
 	struct chardev_priv *priv = filp->private_data;
 
+	guard(rwsem_read)(&priv->pdata->ec_dev_sem);
+	if (!priv->pdata->ec_dev)
+		return -ENODEV;
+
 	if (_IOC_TYPE(cmd) != CROS_EC_DEV_IOC)
 		return -ENOTTY;
 
@@ -374,28 +427,61 @@ static int cros_ec_chardev_probe(struct platform_device *pdev)
 {
 	struct cros_ec_dev *ec = dev_get_drvdata(pdev->dev.parent);
 	struct cros_ec_platform *ec_platform = dev_get_platdata(ec->dev);
-	struct miscdevice *misc;
+	struct chardev_pdata *pdata;
+	int ret;
 
-	/* Create a char device: we want to create it anew */
-	misc = devm_kzalloc(&pdev->dev, sizeof(*misc), GFP_KERNEL);
-	if (!misc)
+	pdata = kzalloc_obj(*pdata);
+	if (!pdata)
 		return -ENOMEM;
 
-	misc->minor = MISC_DYNAMIC_MINOR;
-	misc->fops = &chardev_fops;
-	misc->name = ec_platform->ec_name;
-	misc->parent = pdev->dev.parent;
+	platform_set_drvdata(pdev, pdata);
+	kref_init(&pdata->kref);
+	init_rwsem(&pdata->ec_dev_sem);
+	pdata->ec_dev = ec->ec_dev;
+	pdata->cmd_offset = ec->cmd_offset;
+	BLOCKING_INIT_NOTIFIER_HEAD(&pdata->subscribers);
+	pdata->relay.notifier_call = cros_ec_chardev_relay_event;
+	ret = blocking_notifier_chain_register(&pdata->ec_dev->event_notifier,
+					       &pdata->relay);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register event notifier\n");
+		goto err_put_pdata;
+	}
 
-	dev_set_drvdata(&pdev->dev, misc);
+	pdata->misc.minor = MISC_DYNAMIC_MINOR;
+	pdata->misc.fops = &chardev_fops;
+	pdata->misc.name = ec_platform->ec_name;
+	pdata->misc.parent = pdev->dev.parent;
 
-	return misc_register(misc);
+	ret = misc_register(&pdata->misc);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to register misc device\n");
+		goto err_unregister_notifier;
+	}
+
+	return 0;
+err_unregister_notifier:
+	blocking_notifier_chain_unregister(&pdata->ec_dev->event_notifier,
+					   &pdata->relay);
+err_put_pdata:
+	kref_put(&pdata->kref, chardev_pdata_release);
+	return ret;
 }
 
 static void cros_ec_chardev_remove(struct platform_device *pdev)
 {
-	struct miscdevice *misc = dev_get_drvdata(&pdev->dev);
+	struct chardev_pdata *pdata = platform_get_drvdata(pdev);
+	struct cros_ec_device *ec_dev = pdata->ec_dev;
 
-	misc_deregister(misc);
+	/* stop new fops from being created */
+	misc_deregister(&pdata->misc);
+	/* stop existing fops from running */
+	scoped_guard(rwsem_write, &pdata->ec_dev_sem)
+		pdata->ec_dev = NULL;
+
+	blocking_notifier_chain_unregister(&ec_dev->event_notifier,
+					   &pdata->relay);
+	kref_put(&pdata->kref, chardev_pdata_release);
 }
 
 static const struct platform_device_id cros_ec_chardev_id[] = {

drivers/platform/chrome/cros_ec_i2c.c

@@ -348,7 +348,7 @@ MODULE_DEVICE_TABLE(of, cros_ec_i2c_of_match);
 #endif
 
 static const struct i2c_device_id cros_ec_i2c_id[] = {
-	{ "cros-ec-i2c" },
+	{ .name = "cros-ec-i2c" },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, cros_ec_i2c_id);

drivers/platform/chrome/cros_ec_sensorhub.c

@@ -122,8 +122,12 @@ static int cros_ec_sensorhub_register(struct device *dev,
 		sensor_type[sensorhub->resp->info.type]++;
 	}
 
-	if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2)
+	if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2) {
 		ec->has_kb_wake_angle = true;
+		if (ec->group && sysfs_update_group(&ec->class_dev.kobj,
+						    ec->group))
+			dev_warn(dev, "Unable to update sysfs");
+	}
 
 	if (cros_ec_check_features(ec,
 				   EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {

drivers/platform/chrome/cros_ec_sysfs.c

@@ -405,7 +405,8 @@ static int cros_ec_sysfs_probe(struct platform_device *pd)
 	struct device *dev = &pd->dev;
 	int ret;
 
-	ret = sysfs_create_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
+	ec_dev->group = &cros_ec_attr_group;
+	ret = sysfs_create_group(&ec_dev->class_dev.kobj, ec_dev->group);
 	if (ret < 0)
 		dev_err(dev, "failed to create attributes. err=%d\n", ret);
 
@@ -416,7 +417,7 @@ static void cros_ec_sysfs_remove(struct platform_device *pd)
 {
 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pd->dev.parent);
 
-	sysfs_remove_group(&ec_dev->class_dev.kobj, &cros_ec_attr_group);
+	sysfs_remove_group(&ec_dev->class_dev.kobj, ec_dev->group);
 }
 
 static const struct platform_device_id cros_ec_sysfs_id[] = {

drivers/platform/chrome/cros_hps_i2c.c

@@ -131,7 +131,7 @@ static int hps_resume(struct device *dev)
 static DEFINE_RUNTIME_DEV_PM_OPS(hps_pm_ops, hps_suspend, hps_resume, NULL);
 
 static const struct i2c_device_id hps_i2c_id[] = {
-	{ "cros-hps" },
+	{ .name = "cros-hps" },
 	{ }
 };
 MODULE_DEVICE_TABLE(i2c, hps_i2c_id);

drivers/platform/chrome/cros_kbd_led_backlight.c

@@ -32,12 +32,11 @@ struct keyboard_led {
  * @brightness_set_blocking:	Set LED brightness level.  It can block the
  *				caller for the time required for accessing a
  *				LED device register
- * @max_brightness:		Maximum brightness.
  *
  * See struct led_classdev in include/linux/leds.h for more details.
  */
 struct keyboard_led_drvdata {
-	int (*init)(struct platform_device *pdev);
+	int (*init)(struct platform_device *pdev, struct keyboard_led *keyboard_led);
 
 	enum led_brightness (*brightness_get)(struct led_classdev *led_cdev);
 
@@ -45,12 +44,8 @@ struct keyboard_led_drvdata {
 			       enum led_brightness brightness);
 	int (*brightness_set_blocking)(struct led_classdev *led_cdev,
 				       enum led_brightness brightness);
-
-	enum led_brightness max_brightness;
 };
 
-#define KEYBOARD_BACKLIGHT_MAX 100
-
 #ifdef CONFIG_ACPI
 
 /* Keyboard LED ACPI Device must be defined in firmware */
@@ -94,7 +89,8 @@ keyboard_led_get_brightness_acpi(struct led_classdev *cdev)
 	return brightness;
 }
 
-static int keyboard_led_init_acpi(struct platform_device *pdev)
+static int keyboard_led_init_acpi(struct platform_device *pdev,
+				  struct keyboard_led *keyboard_led)
 {
 	acpi_handle handle;
 	acpi_status status;
@@ -116,17 +112,15 @@ static const struct keyboard_led_drvdata keyboard_led_drvdata_acpi = {
 	.init = keyboard_led_init_acpi,
 	.brightness_set = keyboard_led_set_brightness_acpi,
 	.brightness_get = keyboard_led_get_brightness_acpi,
-	.max_brightness = KEYBOARD_BACKLIGHT_MAX,
 };
 
 #endif /* CONFIG_ACPI */
 
-#if IS_ENABLED(CONFIG_MFD_CROS_EC_DEV)
-static int keyboard_led_init_ec_pwm_mfd(struct platform_device *pdev)
+static int keyboard_led_init_ec_pwm_mfd(struct platform_device *pdev,
+					struct keyboard_led *keyboard_led)
 {
 	struct cros_ec_dev *ec_dev = dev_get_drvdata(pdev->dev.parent);
 	struct cros_ec_device *cros_ec = ec_dev->ec_dev;
-	struct keyboard_led *keyboard_led = platform_get_drvdata(pdev);
 
 	keyboard_led->ec = cros_ec;
 
@@ -175,15 +169,8 @@ static const struct keyboard_led_drvdata keyboard_led_drvdata_ec_pwm_mfd = {
 	.init = keyboard_led_init_ec_pwm_mfd,
 	.brightness_set_blocking = keyboard_led_set_brightness_ec_pwm,
 	.brightness_get = keyboard_led_get_brightness_ec_pwm,
-	.max_brightness = KEYBOARD_BACKLIGHT_MAX,
 };
 
-#else /* IS_ENABLED(CONFIG_MFD_CROS_EC_DEV) */
-
-static const struct keyboard_led_drvdata keyboard_led_drvdata_ec_pwm_mfd = {};
-
-#endif /* IS_ENABLED(CONFIG_MFD_CROS_EC_DEV) */
-
 static int keyboard_led_is_mfd_device(struct platform_device *pdev)
 {
 	return IS_ENABLED(CONFIG_MFD_CROS_EC_DEV) && mfd_get_cell(pdev);
@@ -205,17 +192,16 @@ static int keyboard_led_probe(struct platform_device *pdev)
 	keyboard_led = devm_kzalloc(&pdev->dev, sizeof(*keyboard_led), GFP_KERNEL);
 	if (!keyboard_led)
 		return -ENOMEM;
-	platform_set_drvdata(pdev, keyboard_led);
 
 	if (drvdata->init) {
-		err = drvdata->init(pdev);
+		err = drvdata->init(pdev, keyboard_led);
 		if (err)
 			return err;
 	}
 
 	keyboard_led->cdev.name = "chromeos::kbd_backlight";
 	keyboard_led->cdev.flags |= LED_CORE_SUSPENDRESUME | LED_REJECT_NAME_CONFLICT;
-	keyboard_led->cdev.max_brightness = drvdata->max_brightness;
+	keyboard_led->cdev.max_brightness = 100;
 	keyboard_led->cdev.brightness_set = drvdata->brightness_set;
 	keyboard_led->cdev.brightness_set_blocking = drvdata->brightness_set_blocking;
 	keyboard_led->cdev.brightness_get = drvdata->brightness_get;

drivers/platform/chrome/wilco_ec/event.c

@@ -452,8 +452,13 @@ static void hangup_device(struct event_device_data *dev_data)
 static int event_device_probe(struct platform_device *pdev)
 {
 	struct event_device_data *dev_data;
+	struct acpi_device *adev;
 	int error, minor;
 
+	adev = ACPI_COMPANION(&pdev->dev);
+	if (!adev)
+		return -ENODEV;
+
 	minor = ida_alloc_max(&event_ida, EVENT_MAX_DEV-1, GFP_KERNEL);
 	if (minor < 0) {
 		error = minor;
@@ -494,8 +499,7 @@ static int event_device_probe(struct platform_device *pdev)
 		goto free_dev_data;
 
 	/* Install an ACPI notify handler. */
-	error = acpi_dev_install_notify_handler(ACPI_COMPANION(&pdev->dev),
-						ACPI_DEVICE_NOTIFY,
+	error = acpi_dev_install_notify_handler(adev, ACPI_DEVICE_NOTIFY,
 						event_device_notify, &pdev->dev);
 	if (error)
 		goto free_cdev;

include/linux/platform_data/cros_ec_proto.h

@@ -228,6 +228,7 @@ struct cros_ec_platform {
 /**
  * struct cros_ec_dev - ChromeOS EC device entry point.
  * @class_dev: Device structure used in sysfs.
+ * @group: sysfs attributes groups for this EC.
  * @ec_dev: cros_ec_device structure to talk to the physical device.
  * @dev: Pointer to the platform device.
  * @debug_info: cros_ec_debugfs structure for debugging information.
@@ -237,6 +238,7 @@ struct cros_ec_platform {
  */
 struct cros_ec_dev {
 	struct device class_dev;
+	const struct attribute_group *group;
 	struct cros_ec_device *ec_dev;
 	struct device *dev;
 	struct cros_ec_debugfs *debug_info;