Merge tag 'tag-chrome-platform-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux

Pull chrome platform updates from Tzung-Bi Shih:
 "New drivers
   - Driver for ChromeOS human presence sensor

  Cleanups:
   - Add missing property in dt-binding example.
   - Update the availability of properties in dt-binding.
   - Separate dt-binding for ChromeOS fingerprint sensor.

  Improvements:
   - Set PROBE_PREFER_ASYNCHRONOUS for some drivers for shortening boot time.

  Fixes:
   - Fix an use-after-free in cros_ec_typec.

  And minor fixes and cleanups"

* tag 'tag-chrome-platform-for-v6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/chrome-platform/linux:
  platform/chrome: cros_ec_typec: zero out stale pointers
  platform/chrome: cros_usbpd_notify: Fix error handling in cros_usbpd_notify_init()
  platform/chrome: cros_ec: Convert to i2c's .probe_new()
  platform/chrome: cros_ec_lpc: Force synchronous probe
  platform/chrome: cros_ec_spi: Set PROBE_PREFER_ASYNCHRONOUS
  platform/chrome: cros_ec_lightbar: Set PROBE_PREFER_ASYNCHRONOUS
  platform/chrome: cros_ec_debugfs: Set PROBE_PREFER_ASYNCHRONOUS
  platform/chrome: cros_ec_lpc: Mark PROBE_PREFER_ASYNCHRONOUS
  platform/chrome: cros_ec_lpc: Move mec_init to device probe
  platform/chrome: Use kstrtobool() instead of strtobool()
  platform/chrome: cros_ec_lpc_mec: remove cros_ec_lpc_mec_destroy()
  dt-bindings: cros-ec: Add ChromeOS fingerprint binding
  dt-bindings: cros-ec: Reorganize and enforce property availability
  platform/chrome: cros_hps_i2c: make remove callback return void
  platform/chrome: add a driver for HPS

1 files changed, 160 insertions, 0 deletions

diff --git a/drivers/platform/chrome/cros_hps_i2c.c b/drivers/platform/chrome/cros_hps_i2c.c
new file mode 100644
index 000000000000..62ccb1acb5de
--- /dev/null
+++ b/drivers/platform/chrome/cros_hps_i2c.c
@@ -0,0 +1,160 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver for the ChromeOS human presence sensor (HPS), attached via I2C.
+ *
+ * The driver exposes HPS as a character device, although currently no read or
+ * write operations are supported. Instead, the driver only controls the power
+ * state of the sensor, keeping it on only while userspace holds an open file
+ * descriptor to the HPS device.
+ *
+ * Copyright 2022 Google LLC.
+ */
+
+#include <linux/acpi.h>
+#include <linux/fs.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/miscdevice.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+
+#define HPS_ACPI_ID		"GOOG0020"
+
+struct hps_drvdata {
+	struct i2c_client *client;
+	struct miscdevice misc_device;
+	struct gpio_desc *enable_gpio;
+};
+
+static void hps_set_power(struct hps_drvdata *hps, bool state)
+{
+	gpiod_set_value_cansleep(hps->enable_gpio, state);
+}
+
+static int hps_open(struct inode *inode, struct file *file)
+{
+	struct hps_drvdata *hps = container_of(file->private_data,
+					       struct hps_drvdata, misc_device);
+	struct device *dev = &hps->client->dev;
+
+	return pm_runtime_resume_and_get(dev);
+}
+
+static int hps_release(struct inode *inode, struct file *file)
+{
+	struct hps_drvdata *hps = container_of(file->private_data,
+					       struct hps_drvdata, misc_device);
+	struct device *dev = &hps->client->dev;
+
+	return pm_runtime_put(dev);
+}
+
+static const struct file_operations hps_fops = {
+	.owner = THIS_MODULE,
+	.open = hps_open,
+	.release = hps_release,
+};
+
+static int hps_i2c_probe(struct i2c_client *client)
+{
+	struct hps_drvdata *hps;
+	int ret;
+
+	hps = devm_kzalloc(&client->dev, sizeof(*hps), GFP_KERNEL);
+	if (!hps)
+		return -ENOMEM;
+
+	hps->misc_device.parent = &client->dev;
+	hps->misc_device.minor = MISC_DYNAMIC_MINOR;
+	hps->misc_device.name = "cros-hps";
+	hps->misc_device.fops = &hps_fops;
+
+	i2c_set_clientdata(client, hps);
+	hps->client = client;
+
+	/*
+	 * HPS is powered on from firmware before entering the kernel, so we
+	 * acquire the line with GPIOD_OUT_HIGH here to preserve the existing
+	 * state. The peripheral is powered off after successful probe below.
+	 */
+	hps->enable_gpio = devm_gpiod_get(&client->dev, "enable", GPIOD_OUT_HIGH);
+	if (IS_ERR(hps->enable_gpio)) {
+		ret = PTR_ERR(hps->enable_gpio);
+		dev_err(&client->dev, "failed to get enable gpio: %d\n", ret);
+		return ret;
+	}
+
+	ret = misc_register(&hps->misc_device);
+	if (ret) {
+		dev_err(&client->dev, "failed to initialize misc device: %d\n", ret);
+		return ret;
+	}
+
+	hps_set_power(hps, false);
+	pm_runtime_enable(&client->dev);
+	return 0;
+}
+
+static void hps_i2c_remove(struct i2c_client *client)
+{
+	struct hps_drvdata *hps = i2c_get_clientdata(client);
+
+	pm_runtime_disable(&client->dev);
+	misc_deregister(&hps->misc_device);
+
+	/*
+	 * Re-enable HPS, in order to return it to its default state
+	 * (i.e. powered on).
+	 */
+	hps_set_power(hps, true);
+}
+
+static int hps_suspend(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct hps_drvdata *hps = i2c_get_clientdata(client);
+
+	hps_set_power(hps, false);
+	return 0;
+}
+
+static int hps_resume(struct device *dev)
+{
+	struct i2c_client *client = to_i2c_client(dev);
+	struct hps_drvdata *hps = i2c_get_clientdata(client);
+
+	hps_set_power(hps, true);
+	return 0;
+}
+static UNIVERSAL_DEV_PM_OPS(hps_pm_ops, hps_suspend, hps_resume, NULL);
+
+static const struct i2c_device_id hps_i2c_id[] = {
+	{ "cros-hps", 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, hps_i2c_id);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id hps_acpi_id[] = {
+	{ HPS_ACPI_ID, 0 },
+	{ }
+};
+MODULE_DEVICE_TABLE(acpi, hps_acpi_id);
+#endif /* CONFIG_ACPI */
+
+static struct i2c_driver hps_i2c_driver = {
+	.probe_new = hps_i2c_probe,
+	.remove = hps_i2c_remove,
+	.id_table = hps_i2c_id,
+	.driver = {
+		.name = "cros-hps",
+		.pm = &hps_pm_ops,
+		.acpi_match_table = ACPI_PTR(hps_acpi_id),
+	},
+};
+module_i2c_driver(hps_i2c_driver);
+
+MODULE_ALIAS("acpi:" HPS_ACPI_ID);
+MODULE_AUTHOR("Sami Kyöstilä <skyostil@chromium.org>");
+MODULE_DESCRIPTION("Driver for ChromeOS HPS");
+MODULE_LICENSE("GPL");