3 files changed, 309 insertions, 0 deletions

diff --git a/drivers/rtc/Kconfig b/drivers/rtc/Kconfig
index 5e44eaabf457..aa64d5d3fb20 100644
--- a/drivers/rtc/Kconfig
+++ b/drivers/rtc/Kconfig
@@ -1183,4 +1183,20 @@ config RTC_DRV_SNVS
            This driver can also be built as a module, if so, the module
            will be called "rtc-snvs".
 
+comment "HID Sensor RTC drivers"
+
+config RTC_DRV_HID_SENSOR_TIME
+        tristate "HID Sensor Time"
+        depends on USB_HID
+        select IIO
+        select HID_SENSOR_HUB
+        select HID_SENSOR_IIO_COMMON
+        help
+          Say yes here to build support for the HID Sensors of type Time.
+          This drivers makes such sensors available as RTCs.
+
+          If this driver is compiled as a module, it will be named
+          rtc-hid-sensor-time.
+
+
 endif # RTC_CLASS
diff --git a/drivers/rtc/Makefile b/drivers/rtc/Makefile
index ec2988b00a44..60c0414d67fa 100644
--- a/drivers/rtc/Makefile
+++ b/drivers/rtc/Makefile
@@ -53,6 +53,7 @@ obj-$(CONFIG_RTC_DRV_EM3027)	+= rtc-em3027.o
 obj-$(CONFIG_RTC_DRV_EP93XX)    += rtc-ep93xx.o
 obj-$(CONFIG_RTC_DRV_FM3130)    += rtc-fm3130.o
 obj-$(CONFIG_RTC_DRV_GENERIC)   += rtc-generic.o
+obj-$(CONFIG_RTC_DRV_HID_SENSOR_TIME) += rtc-hid-sensor-time.o
 obj-$(CONFIG_RTC_DRV_IMXDI)     += rtc-imxdi.o
 obj-$(CONFIG_RTC_DRV_ISL1208)   += rtc-isl1208.o
 obj-$(CONFIG_RTC_DRV_ISL12022)  += rtc-isl12022.o
diff --git a/drivers/rtc/rtc-hid-sensor-time.c b/drivers/rtc/rtc-hid-sensor-time.c
new file mode 100644
index 000000000000..31c5728ef629
--- /dev/null
+++ b/drivers/rtc/rtc-hid-sensor-time.c
@@ -0,0 +1,292 @@
+/*
+ * HID Sensor Time Driver
+ * Copyright (c) 2012, Alexander Holler.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/module.h>
+#include <linux/hid-sensor-hub.h>
+#include <linux/iio/iio.h>
+#include <linux/rtc.h>
+
+/* Format: HID-SENSOR-usage_id_in_hex */
+/* Usage ID from spec for Time: 0x2000A0 */
+#define DRIVER_NAME "HID-SENSOR-2000a0" /* must be lowercase */
+
+enum hid_time_channel {
+        CHANNEL_SCAN_INDEX_YEAR,
+        CHANNEL_SCAN_INDEX_MONTH,
+        CHANNEL_SCAN_INDEX_DAY,
+        CHANNEL_SCAN_INDEX_HOUR,
+        CHANNEL_SCAN_INDEX_MINUTE,
+        CHANNEL_SCAN_INDEX_SECOND,
+        TIME_RTC_CHANNEL_MAX,
+};
+
+struct hid_time_state {
+        struct hid_sensor_hub_callbacks callbacks;
+        struct hid_sensor_common common_attributes;
+        struct hid_sensor_hub_attribute_info info[TIME_RTC_CHANNEL_MAX];
+        struct rtc_time last_time;
+        spinlock_t lock_last_time;
+        struct completion comp_last_time;
+        struct rtc_time time_buf;
+        struct rtc_device *rtc;
+};
+
+static const u32 hid_time_addresses[TIME_RTC_CHANNEL_MAX] = {
+        HID_USAGE_SENSOR_TIME_YEAR,
+        HID_USAGE_SENSOR_TIME_MONTH,
+        HID_USAGE_SENSOR_TIME_DAY,
+        HID_USAGE_SENSOR_TIME_HOUR,
+        HID_USAGE_SENSOR_TIME_MINUTE,
+        HID_USAGE_SENSOR_TIME_SECOND,
+};
+
+/* Channel names for verbose error messages */
+static const char * const hid_time_channel_names[TIME_RTC_CHANNEL_MAX] = {
+        "year", "month", "day", "hour", "minute", "second",
+};
+
+/* Callback handler to send event after all samples are received and captured */
+static int hid_time_proc_event(struct hid_sensor_hub_device *hsdev,
+                                unsigned usage_id, void *priv)
+{
+        unsigned long flags;
+        struct hid_time_state *time_state = platform_get_drvdata(priv);
+
+        spin_lock_irqsave(&time_state->lock_last_time, flags);
+        time_state->last_time = time_state->time_buf;
+        spin_unlock_irqrestore(&time_state->lock_last_time, flags);
+        complete(&time_state->comp_last_time);
+        return 0;
+}
+
+static int hid_time_capture_sample(struct hid_sensor_hub_device *hsdev,
+                                unsigned usage_id, size_t raw_len,
+                                char *raw_data, void *priv)
+{
+        struct hid_time_state *time_state = platform_get_drvdata(priv);
+        struct rtc_time *time_buf = &time_state->time_buf;
+
+        switch (usage_id) {
+        case HID_USAGE_SENSOR_TIME_YEAR:
+                time_buf->tm_year = *(u8 *)raw_data;
+                if (time_buf->tm_year < 70)
+                        /* assume we are in 1970...2069 */
+                        time_buf->tm_year += 100;
+                break;
+        case HID_USAGE_SENSOR_TIME_MONTH:
+                /* sensor sending the month as 1-12, we need 0-11 */
+                time_buf->tm_mon = *(u8 *)raw_data-1;
+                break;
+        case HID_USAGE_SENSOR_TIME_DAY:
+                time_buf->tm_mday = *(u8 *)raw_data;
+                break;
+        case HID_USAGE_SENSOR_TIME_HOUR:
+                time_buf->tm_hour = *(u8 *)raw_data;
+                break;
+        case HID_USAGE_SENSOR_TIME_MINUTE:
+                time_buf->tm_min = *(u8 *)raw_data;
+                break;
+        case HID_USAGE_SENSOR_TIME_SECOND:
+                time_buf->tm_sec = *(u8 *)raw_data;
+                break;
+        default:
+                return -EINVAL;
+        }
+        return 0;
+}
+
+/* small helper, haven't found any other way */
+static const char *hid_time_attrib_name(u32 attrib_id)
+{
+        static const char unknown[] = "unknown";
+        unsigned i;
+
+        for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) {
+                if (hid_time_addresses[i] == attrib_id)
+                        return hid_time_channel_names[i];
+        }
+        return unknown; /* should never happen */
+}
+
+static int hid_time_parse_report(struct platform_device *pdev,
+                                struct hid_sensor_hub_device *hsdev,
+                                unsigned usage_id,
+                                struct hid_time_state *time_state)
+{
+        int report_id, i;
+
+        for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i)
+                if (sensor_hub_input_get_attribute_info(hsdev,
+                                HID_INPUT_REPORT, usage_id,
+                                hid_time_addresses[i],
+                                &time_state->info[i]) < 0)
+                        return -EINVAL;
+        /* Check the (needed) attributes for sanity */
+        report_id = time_state->info[0].report_id;
+        if (report_id < 0) {
+                dev_err(&pdev->dev, "bad report ID!\n");
+                return -EINVAL;
+        }
+        for (i = 0; i < TIME_RTC_CHANNEL_MAX; ++i) {
+                if (time_state->info[i].report_id != report_id) {
+                        dev_err(&pdev->dev,
+                                "not all needed attributes inside the same report!\n");
+                        return -EINVAL;
+                }
+                if (time_state->info[i].size != 1) {
+                        dev_err(&pdev->dev,
+                                "attribute '%s' not 8 bits wide!\n",
+                                hid_time_attrib_name(
+                                        time_state->info[i].attrib_id));
+                        return -EINVAL;
+                }
+                if (time_state->info[i].units !=
+                                HID_USAGE_SENSOR_UNITS_NOT_SPECIFIED &&
+                                /* allow attribute seconds with unit seconds */
+                                !(time_state->info[i].attrib_id ==
+                                HID_USAGE_SENSOR_TIME_SECOND &&
+                                time_state->info[i].units ==
+                                HID_USAGE_SENSOR_UNITS_SECOND)) {
+                        dev_err(&pdev->dev,
+                                "attribute '%s' hasn't a unit of type 'none'!\n",
+                                hid_time_attrib_name(
+                                        time_state->info[i].attrib_id));
+                        return -EINVAL;
+                }
+                if (time_state->info[i].unit_expo) {
+                        dev_err(&pdev->dev,
+                                "attribute '%s' hasn't a unit exponent of 1!\n",
+                                hid_time_attrib_name(
+                                        time_state->info[i].attrib_id));
+                        return -EINVAL;
+                }
+        }
+
+        return 0;
+}
+
+static int hid_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+        unsigned long flags;
+        struct hid_time_state *time_state =
+                platform_get_drvdata(to_platform_device(dev));
+        int ret;
+
+        INIT_COMPLETION(time_state->comp_last_time);
+        /* get a report with all values through requesting one value */
+        sensor_hub_input_attr_get_raw_value(time_state->common_attributes.hsdev,
+                        HID_USAGE_SENSOR_TIME, hid_time_addresses[0],
+                        time_state->info[0].report_id);
+        /* wait for all values (event) */
+        ret = wait_for_completion_killable_timeout(
+                        &time_state->comp_last_time, HZ*6);
+        if (ret > 0) {
+                /* no error */
+                spin_lock_irqsave(&time_state->lock_last_time, flags);
+                *tm = time_state->last_time;
+                spin_unlock_irqrestore(&time_state->lock_last_time, flags);
+                return 0;
+        }
+        if (!ret)
+                return -EIO; /* timeouted */
+        return ret; /* killed (-ERESTARTSYS) */
+}
+
+static const struct rtc_class_ops hid_time_rtc_ops = {
+        .read_time = hid_rtc_read_time,
+};
+
+static int hid_time_probe(struct platform_device *pdev)
+{
+        int ret = 0;
+        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
+        struct hid_time_state *time_state = devm_kzalloc(&pdev->dev,
+                sizeof(struct hid_time_state), GFP_KERNEL);
+
+        if (time_state == NULL)
+                return -ENOMEM;
+
+        platform_set_drvdata(pdev, time_state);
+
+        spin_lock_init(&time_state->lock_last_time);
+        init_completion(&time_state->comp_last_time);
+        time_state->common_attributes.hsdev = hsdev;
+        time_state->common_attributes.pdev = pdev;
+
+        ret = hid_sensor_parse_common_attributes(hsdev,
+                                HID_USAGE_SENSOR_TIME,
+                                &time_state->common_attributes);
+        if (ret) {
+                dev_err(&pdev->dev, "failed to setup common attributes!\n");
+                return ret;
+        }
+
+        ret = hid_time_parse_report(pdev, hsdev, HID_USAGE_SENSOR_TIME,
+                                        time_state);
+        if (ret) {
+                dev_err(&pdev->dev, "failed to setup attributes!\n");
+                return ret;
+        }
+
+        time_state->callbacks.send_event = hid_time_proc_event;
+        time_state->callbacks.capture_sample = hid_time_capture_sample;
+        time_state->callbacks.pdev = pdev;
+        ret = sensor_hub_register_callback(hsdev, HID_USAGE_SENSOR_TIME,
+                                        &time_state->callbacks);
+        if (ret < 0) {
+                dev_err(&pdev->dev, "register callback failed!\n");
+                return ret;
+        }
+
+        time_state->rtc = rtc_device_register("hid-sensor-time",
+                                &pdev->dev, &hid_time_rtc_ops, THIS_MODULE);
+
+        if (IS_ERR(time_state->rtc)) {
+                dev_err(&pdev->dev, "rtc device register failed!\n");
+                return PTR_ERR(time_state->rtc);
+        }
+
+        return ret;
+}
+
+static int hid_time_remove(struct platform_device *pdev)
+{
+        struct hid_sensor_hub_device *hsdev = pdev->dev.platform_data;
+        struct hid_time_state *time_state = platform_get_drvdata(pdev);
+
+        rtc_device_unregister(time_state->rtc);
+        sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TIME);
+
+        return 0;
+}
+
+static struct platform_driver hid_time_platform_driver = {
+        .driver = {
+                .name   = DRIVER_NAME,
+                .owner  = THIS_MODULE,
+        },
+        .probe          = hid_time_probe,
+        .remove         = hid_time_remove,
+};
+module_platform_driver(hid_time_platform_driver);
+
+MODULE_DESCRIPTION("HID Sensor Time");
+MODULE_AUTHOR("Alexander Holler <holler@ahsoftware.de>");
+MODULE_LICENSE("GPL");