iio / platform: cros_ec: Add cros-ec-sensorhub driver

Similar to HID sensor stack, the new driver sits between cros-ec-dev
and the IIO device drivers:

The EC based IIO device topology would be:

iio:device1 ->
   ...0/0000:00:1f.0/PNP0C09:00/GOOG0004:00/cros-ec-dev.6.auto/
                                            cros-ec-sensorhub.7.auto/
                                            cros-ec-accel.15.auto/
                                            iio:device1

It will be expanded to control EC sensor FIFO.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
[Fix "unknown type name 'uint32_t'" type errors]
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>

diff --git a/drivers/iio/common/cros_ec_sensors/Kconfig b/drivers/iio/common/cros_ec_sensors/Kconfig
index cdbb29cfb9076b738071bbb3a3dfc696e1a8ebaa..fefad95727907d2b5971c727deaf51170c733b78 100644 (file)
--- a/drivers/iio/common/cros_ec_sensors/Kconfig
+++ b/drivers/iio/common/cros_ec_sensors/Kconfig
@@ -4,7 +4,7 @@
 #
 config IIO_CROS_EC_SENSORS_CORE
        tristate "ChromeOS EC Sensors Core"
-       depends on SYSFS && CROS_EC
+       depends on SYSFS && CROS_EC_SENSORHUB
        select IIO_BUFFER
        select IIO_TRIGGERED_BUFFER
        help

diff --git a/drivers/platform/chrome/Kconfig b/drivers/platform/chrome/Kconfig
index ee5f08ea57b6cc7cca513890347a4a559805a271..884ac9a287f25c461ec69ee5e515e335a5e2881d 100644 (file)
--- a/drivers/platform/chrome/Kconfig
+++ b/drivers/platform/chrome/Kconfig
@@ -190,6 +190,18 @@ config CROS_EC_DEBUGFS
          To compile this driver as a module, choose M here: the
          module will be called cros_ec_debugfs.
 
+config CROS_EC_SENSORHUB
+       tristate "ChromeOS EC MEMS Sensor Hub"
+       depends on CROS_EC
+       help
+         Allow loading IIO sensors. This driver is loaded by MFD and will in
+         turn query the EC and register the sensors.
+         It also spreads the sensor data coming from the EC to the IIO sensor
+         object.
+
+         To compile this driver as a module, choose M here: the
+         module will be called cros_ec_sensorhub.
+
 config CROS_EC_SYSFS
        tristate "ChromeOS EC control and information through sysfs"
        depends on MFD_CROS_EC_DEV && SYSFS

diff --git a/drivers/platform/chrome/Makefile b/drivers/platform/chrome/Makefile
index 477ec3d1d1c98719126d92769900daea04358481..aacd5920d8a1809621f57d141a9ec4a1b6c64909 100644 (file)
--- a/drivers/platform/chrome/Makefile
+++ b/drivers/platform/chrome/Makefile
@@ -19,6 +19,7 @@ obj-$(CONFIG_CROS_EC_CHARDEV)         += cros_ec_chardev.o
 obj-$(CONFIG_CROS_EC_LIGHTBAR)         += cros_ec_lightbar.o
 obj-$(CONFIG_CROS_EC_VBC)              += cros_ec_vbc.o
 obj-$(CONFIG_CROS_EC_DEBUGFS)          += cros_ec_debugfs.o
+obj-$(CONFIG_CROS_EC_SENSORHUB)                += cros_ec_sensorhub.o
 obj-$(CONFIG_CROS_EC_SYSFS)            += cros_ec_sysfs.o
 obj-$(CONFIG_CROS_USBPD_LOGGER)                += cros_usbpd_logger.o
 

diff --git a/drivers/platform/chrome/cros_ec_sensorhub.c b/drivers/platform/chrome/cros_ec_sensorhub.c
new file mode 100644 (file)
index 0000000..04d8879
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_sensorhub.c
@@ -0,0 +1,199 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Sensor HUB driver that discovers sensors behind a ChromeOS Embedded
+ * Controller.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#include <linux/init.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/mfd/cros_ec.h>
+#include <linux/platform_data/cros_ec_commands.h>
+#include <linux/platform_data/cros_ec_proto.h>
+#include <linux/platform_data/cros_ec_sensorhub.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+
+#define DRV_NAME               "cros-ec-sensorhub"
+
+static void cros_ec_sensorhub_free_sensor(void *arg)
+{
+       struct platform_device *pdev = arg;
+
+       platform_device_unregister(pdev);
+}
+
+static int cros_ec_sensorhub_allocate_sensor(struct device *parent,
+                                            char *sensor_name,
+                                            int sensor_num)
+{
+       struct cros_ec_sensor_platform sensor_platforms = {
+               .sensor_num = sensor_num,
+       };
+       struct platform_device *pdev;
+
+       pdev = platform_device_register_data(parent, sensor_name,
+                                            PLATFORM_DEVID_AUTO,
+                                            &sensor_platforms,
+                                            sizeof(sensor_platforms));
+       if (IS_ERR(pdev))
+               return PTR_ERR(pdev);
+
+       return devm_add_action_or_reset(parent,
+                                       cros_ec_sensorhub_free_sensor,
+                                       pdev);
+}
+
+static int cros_ec_sensorhub_register(struct device *dev,
+                                     struct cros_ec_sensorhub *sensorhub)
+{
+       int sensor_type[MOTIONSENSE_TYPE_MAX] = { 0 };
+       struct cros_ec_dev *ec = sensorhub->ec;
+       struct ec_params_motion_sense *params;
+       struct ec_response_motion_sense *resp;
+       struct cros_ec_command *msg;
+       int ret, i, sensor_num;
+       char *name;
+
+       sensor_num = cros_ec_get_sensor_count(ec);
+       if (sensor_num < 0) {
+               dev_err(dev,
+                       "Unable to retrieve sensor information (err:%d)\n",
+                       sensor_num);
+               return sensor_num;
+       }
+
+       if (sensor_num == 0) {
+               dev_err(dev, "Zero sensors reported.\n");
+               return -EINVAL;
+       }
+
+       /* Prepare a message to send INFO command to each sensor. */
+       msg = kzalloc(sizeof(*msg) + max(sizeof(*params), sizeof(*resp)),
+                     GFP_KERNEL);
+       if (!msg)
+               return -ENOMEM;
+
+       msg->version = 1;
+       msg->command = EC_CMD_MOTION_SENSE_CMD + ec->cmd_offset;
+       msg->outsize = sizeof(*params);
+       msg->insize = sizeof(*resp);
+       params = (struct ec_params_motion_sense *)msg->data;
+       resp = (struct ec_response_motion_sense *)msg->data;
+
+       for (i = 0; i < sensor_num; i++) {
+               params->cmd = MOTIONSENSE_CMD_INFO;
+               params->info.sensor_num = i;
+
+               ret = cros_ec_cmd_xfer_status(ec->ec_dev, msg);
+               if (ret < 0) {
+                       dev_warn(dev, "no info for EC sensor %d : %d/%d\n",
+                                i, ret, msg->result);
+                       continue;
+               }
+
+               switch (resp->info.type) {
+               case MOTIONSENSE_TYPE_ACCEL:
+                       name = "cros-ec-accel";
+                       break;
+               case MOTIONSENSE_TYPE_BARO:
+                       name = "cros-ec-baro";
+                       break;
+               case MOTIONSENSE_TYPE_GYRO:
+                       name = "cros-ec-gyro";
+                       break;
+               case MOTIONSENSE_TYPE_MAG:
+                       name = "cros-ec-mag";
+                       break;
+               case MOTIONSENSE_TYPE_PROX:
+                       name = "cros-ec-prox";
+                       break;
+               case MOTIONSENSE_TYPE_LIGHT:
+                       name = "cros-ec-light";
+                       break;
+               case MOTIONSENSE_TYPE_ACTIVITY:
+                       name = "cros-ec-activity";
+                       break;
+               default:
+                       dev_warn(dev, "unknown type %d\n", resp->info.type);
+                       continue;
+               }
+
+               ret = cros_ec_sensorhub_allocate_sensor(dev, name, i);
+               if (ret)
+                       goto error;
+
+               sensor_type[resp->info.type]++;
+       }
+
+       if (sensor_type[MOTIONSENSE_TYPE_ACCEL] >= 2)
+               ec->has_kb_wake_angle = true;
+
+       if (cros_ec_check_features(ec,
+                                  EC_FEATURE_REFINED_TABLET_MODE_HYSTERESIS)) {
+               ret = cros_ec_sensorhub_allocate_sensor(dev,
+                                                       "cros-ec-lid-angle",
+                                                       0);
+               if (ret)
+                       goto error;
+       }
+
+       kfree(msg);
+       return 0;
+
+error:
+       kfree(msg);
+       return ret;
+}
+
+static int cros_ec_sensorhub_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct cros_ec_sensorhub *data;
+       int ret;
+       int i;
+
+       data = devm_kzalloc(dev, sizeof(struct cros_ec_sensorhub), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       data->ec = dev_get_drvdata(dev->parent);
+       dev_set_drvdata(dev, data);
+
+       /* Check whether this EC is a sensor hub. */
+       if (cros_ec_check_features(data->ec, EC_FEATURE_MOTION_SENSE)) {
+               ret = cros_ec_sensorhub_register(dev, data);
+               if (ret)
+                       return ret;
+       } else {
+               /*
+                * If the device has sensors but does not claim to
+                * be a sensor hub, we are in legacy mode.
+                */
+               for (i = 0; i < 2; i++) {
+                       ret = cros_ec_sensorhub_allocate_sensor(dev,
+                                               "cros-ec-accel-legacy", i);
+                       if (ret)
+                               return ret;
+               }
+       }
+
+       return 0;
+}
+
+static struct platform_driver cros_ec_sensorhub_driver = {
+       .driver = {
+               .name = DRV_NAME,
+       },
+       .probe = cros_ec_sensorhub_probe,
+};
+
+module_platform_driver(cros_ec_sensorhub_driver);
+
+MODULE_ALIAS("platform:" DRV_NAME);
+MODULE_AUTHOR("Gwendal Grignou <gwendal@chromium.org>");
+MODULE_DESCRIPTION("ChromeOS EC MEMS Sensor Hub Driver");
+MODULE_LICENSE("GPL");

diff --git a/include/linux/platform_data/cros_ec_sensorhub.h b/include/linux/platform_data/cros_ec_sensorhub.h
new file mode 100644 (file)
index 0000000..5f6f9bb
--- /dev/null
+++ b/include/linux/platform_data/cros_ec_sensorhub.h
@@ -0,0 +1,22 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Chrome OS EC MEMS Sensor Hub driver.
+ *
+ * Copyright 2019 Google LLC
+ */
+
+#ifndef __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H
+#define __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H
+
+#include <linux/platform_data/cros_ec_commands.h>
+
+/**
+ * struct cros_ec_sensorhub - Sensor Hub device data.
+ *
+ * @ec: Embedded Controller where the hub is located.
+ */
+struct cros_ec_sensorhub {
+       struct cros_ec_dev *ec;
+};
+
+#endif   /* __LINUX_PLATFORM_DATA_CROS_EC_SENSORHUB_H */