On Wed, 2015-01-21 at 21:53 +0000, Jonathan Cameron wrote: > On 07/01/15 18:24, Srinivas Pandruvada wrote: > > HID sensor hub exports several sensor which are fusion sensors, where > > data is interpreted from one or more sensors. Some of them can't be > > exported via IIO like sysfs as the user space download some firmware, > > which defines what sensor will look like. They can be a part of a > > collection. > This functionality is beginning to turn up on a number of devices. > I'd argue that where at all possible, we should try for standard > interfaces on the resulting 'fused sensors'. Still you do indeed > always need a means of uploading the firmware! I will submitted RFCs, once I see in production releases.
Currently planning to use misc driver for FW update. What do you think about using dev/iio:deviceX for such case to download FW for each sensor? We also need mechanism to initiate and reset after FW download. Thanks, Srinivas > > Creating a MFD cell for a collection to write a standalone driver > > to manage collections. Most of the time they will be propritery drivers > > may not be even upstreamed. This patch allows framework to have > > capability to write such drivers. > > > > Signed-off-by: Srinivas Pandruvada <[email protected]> > > > > A few comments inline... > > How does userspace download a firmware? > > > --- > > drivers/hid/hid-sensor-hub.c | 50 > > ++++++++++++++++++++++++++++++++++++++---- > > include/linux/hid-sensor-ids.h | 2 ++ > > 2 files changed, 48 insertions(+), 4 deletions(-) > > > > diff --git a/drivers/hid/hid-sensor-hub.c b/drivers/hid/hid-sensor-hub.c > > index 865cd56..83b6e15 100644 > > --- a/drivers/hid/hid-sensor-hub.c > > +++ b/drivers/hid/hid-sensor-hub.c > > @@ -119,11 +119,12 @@ static struct hid_sensor_hub_callbacks > > *sensor_hub_get_callback( > > > > spin_lock_irqsave(&pdata->dyn_callback_lock, flags); > > list_for_each_entry(callback, &pdata->dyn_callback_list, list) > > - if (callback->usage_id == usage_id && > > + if (callback->usage_id == HID_USAGE_SENSOR_TYPE_COLLECTION || > > + (callback->usage_id == usage_id && > > (collection_index >= > > callback->hsdev->start_collection_index) && > > (collection_index < > > - callback->hsdev->end_collection_index)) { > > + callback->hsdev->end_collection_index))) { > > *priv = callback->priv; > > *hsdev = callback->hsdev; > > spin_unlock_irqrestore(&pdata->dyn_callback_lock, > > @@ -159,7 +160,12 @@ int sensor_hub_register_callback(struct > > hid_sensor_hub_device *hsdev, > > callback->usage_callback = usage_callback; > > callback->usage_id = usage_id; > > callback->priv = NULL; > > - list_add_tail(&callback->list, &pdata->dyn_callback_list); > > + /* Give higher priority to collection device, so add to front */ > Comment should probably state why we want to give them higher priorities. > > > + if (usage_id == HID_USAGE_SENSOR_TYPE_COLLECTION) > > + list_add(&callback->list, &pdata->dyn_callback_list); > > + else > > + list_add_tail(&callback->list, &pdata->dyn_callback_list); > > + > > spin_unlock_irqrestore(&pdata->dyn_callback_lock, flags); > > > > return 0; > > @@ -547,6 +553,37 @@ static __u8 *sensor_hub_report_fixup(struct hid_device > > *hdev, __u8 *rdesc, > > return rdesc; > > } > > > > +static int sensor_hub_add_collection_device(struct hid_device *hdev, > > + struct sensor_hub_data *sd) > > +{ > > + struct hid_sensor_hub_device *hsdev; > > + char *name; > > + > > + hsdev = devm_kzalloc(&hdev->dev, sizeof(*hsdev), GFP_KERNEL); > > + if (!hsdev) > > + return -ENOMEM; > > + > > + hsdev->hdev = hdev; > > + hsdev->vendor_id = hdev->vendor; > > + hsdev->product_id = hdev->product; > > + hsdev->usage = HID_USAGE_SENSOR_TYPE_COLLECTION; > > + mutex_init(&hsdev->mutex); > > + name = devm_kasprintf(&hdev->dev, GFP_KERNEL, "HID-SENSOR-%x", > > + HID_USAGE_SENSOR_TYPE_COLLECTION); > > + if (name == NULL) { > > + hid_err(hdev, "Failed MFD device name\n"); > > + return -ENOMEM; > > + } > > + sd->hid_sensor_hub_client_devs[sd->hid_sensor_client_cnt].name = name; > > + sd->hid_sensor_hub_client_devs[ > > + sd->hid_sensor_client_cnt].platform_data = hsdev; > Odd breaking up of the line... Perhaps break before .platform_data instead? > > + sd->hid_sensor_hub_client_devs[ > > + sd->hid_sensor_client_cnt].pdata_size = sizeof(*hsdev); > > + sd->hid_sensor_client_cnt++; > > + > > + return 0; > > +} > > + > > static int sensor_hub_probe(struct hid_device *hdev, > > const struct hid_device_id *id) > > { > > @@ -591,7 +628,8 @@ static int sensor_hub_probe(struct hid_device *hdev, > > ret = -EINVAL; > > goto err_stop_hw; > > } > > - sd->hid_sensor_hub_client_devs = devm_kzalloc(&hdev->dev, dev_cnt * > > + sd->hid_sensor_hub_client_devs = devm_kzalloc(&hdev->dev, > > + (dev_cnt + 1) * > > sizeof(struct mfd_cell), > > GFP_KERNEL); > > if (sd->hid_sensor_hub_client_devs == NULL) { > > @@ -645,6 +683,10 @@ static int sensor_hub_probe(struct hid_device *hdev, > > if (last_hsdev) > > last_hsdev->end_collection_index = i; > > > > + ret = sensor_hub_add_collection_device(hdev, sd); > > + if (ret) > > + goto err_stop_hw; > > + > > ret = mfd_add_hotplug_devices(&hdev->dev, > > sd->hid_sensor_hub_client_devs, > > sd->hid_sensor_client_cnt); > > diff --git a/include/linux/hid-sensor-ids.h b/include/linux/hid-sensor-ids.h > > index 109f0e6..300ffea 100644 > > --- a/include/linux/hid-sensor-ids.h > > +++ b/include/linux/hid-sensor-ids.h > > @@ -21,6 +21,8 @@ > > > > #define HID_MAX_PHY_DEVICES 0xFF > > > > +#define HID_USAGE_SENSOR_TYPE_COLLECTION 0x200001 > > + > > /* Accel 3D (200073) */ > > #define HID_USAGE_SENSOR_ACCEL_3D 0x200073 > > #define HID_USAGE_SENSOR_DATA_ACCELERATION 0x200452 > > > -- To unsubscribe from this list: send the line "unsubscribe linux-input" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
