On 11/06/15 15:54, Simon Wood wrote:
> [resent as I screwed up addressing... sorry]
>
> This patch is a RFC/POC for the idea of using the iio-subsystem as the
> 'proper' way to communicate the state of motion enabled controllers to
> the Linux internals.
Sounds good to me.
>
> I have started with the hid-sony driver, with support for the SixAxis's
> 3 Accelerometers. Proper trigger/buffer support will follow shortly, along
> with support for the DS4 and PSMove controllers (which have a much more
> extensive set of motion hardware).
Good stuff.
>
> Once the sensor data is available (over iio) I envision that it will be
> considerably easier to write motion tracking, flight control and AHRS
> software in a consistant manner.
Cool :) Clearly as Bastien has raised, depending on use case some generic
userspace support to expose these to non root users might be needed.
>
> Hopefully this will become the standard way of connecting controllers,
> motion controls and head mounted displays.
A few bits and bobs inline.
Jonathan
> ---
> drivers/hid/hid-sony.c | 175 +++++++++++++++++++++++++++++++++++++++++++++++++
Hmm. This driver is already a substantial mash up of a number of different
types of driver (as far as linux is concerned), with input, battery and led
drivers. Might be worth considering a more formal MFD approach as it'll
break the driver up into a number of sub components that will then sit
in the various subsystems in a cleaner fashion.
Just a thought!
> 1 file changed, 175 insertions(+)
>
> diff --git a/drivers/hid/hid-sony.c b/drivers/hid/hid-sony.c
> index 6ca96ce..79afae6 100644
> --- a/drivers/hid/hid-sony.c
> +++ b/drivers/hid/hid-sony.c
> @@ -36,6 +36,7 @@
> #include <linux/list.h>
> #include <linux/idr.h>
> #include <linux/input/mt.h>
> +#include <linux/iio/iio.h>
>
> #include "hid-ids.h"
>
> @@ -54,6 +55,7 @@
> DUALSHOCK4_CONTROLLER)
> #define SONY_BATTERY_SUPPORT (SIXAXIS_CONTROLLER | DUALSHOCK4_CONTROLLER)
> #define SONY_FF_SUPPORT (SIXAXIS_CONTROLLER | DUALSHOCK4_CONTROLLER)
> +#define SONY_IIO_SUPPORT SIXAXIS_CONTROLLER
>
> #define MAX_LEDS 4
>
> @@ -835,6 +837,23 @@ struct sony_sc {
> __u8 led_delay_on[MAX_LEDS];
> __u8 led_delay_off[MAX_LEDS];
> __u8 led_count;
> +
> +#if IS_BUILTIN(CONFIG_IIO) || \
> + (IS_MODULE(CONFIG_IIO) && IS_MODULE(CONFIG_HID_SONY))
> + struct iio_dev *indio_dev;
> + __u16 last_acc[3];
> + __u16 last_gyro[3];
> +};
> +
> +enum sony_iio_axis {
> + AXIS_X,
> + AXIS_Y,
> + AXIS_Z,
> +};
> +
> +struct sony_iio {
> + struct sony_sc *sc;
> +#endif
> };
>
> static __u8 *sixaxis_fixup(struct hid_device *hdev, __u8 *rdesc,
> @@ -1047,6 +1066,12 @@ static int sony_raw_event(struct hid_device *hdev, struct hid_report *report,
> swap(rd[45], rd[46]);
> swap(rd[47], rd[48]);
>
> +#if IS_BUILTIN(CONFIG_IIO) || \
> + (IS_MODULE(CONFIG_IIO) && IS_MODULE(CONFIG_HID_SONY))
> + sc->last_acc[0] = (rd[42] << 8) + rd[41];
> + sc->last_acc[1] = (rd[44] << 8) + rd[43];
> + sc->last_acc[2] = (rd[46] << 8) + rd[45];
> +#endif
> sixaxis_parse_report(sc, rd, size);
> } else if (((sc->quirks & DUALSHOCK4_CONTROLLER_USB) && rd[0] == 0x01 &&
> size == 64) || ((sc->quirks & DUALSHOCK4_CONTROLLER_BT)
> @@ -1769,6 +1794,136 @@ static void sony_battery_remove(struct sony_sc *sc)
> sc->battery_desc.name = NULL;
> }
>
> +#if IS_BUILTIN(CONFIG_IIO) || \
> + (IS_MODULE(CONFIG_IIO) && IS_MODULE(CONFIG_HID_SONY))
> +
> +static int sony_iio_read_raw(struct iio_dev *indio_dev,
> + struct iio_chan_spec const *chan,
> + int *val, int *val2,
> + long mask)
> +{
> + struct sony_iio *data = iio_priv(indio_dev);
I'd be tempted to have the sc as the local variable here as there
is nothing else in sony_iio at the moment and it'll save you a few
characters on every reference to it below.
> + int ret;
> + u32 temp;
> +
> + switch (mask) {
> + case IIO_CHAN_INFO_RAW:
> + switch (chan->type) {
> + case IIO_ACCEL:
> + *val = data->sc->last_acc[chan->scan_index];
You can use scan_index for this I suppose, but that's really meant for
location in the buffer. We have iio_chan->address for this sort of
lookup index. Now if they happen to be the same it doesn't really
matter!
Not sure whether it is better to use the last reading obtained, or
wait for a new one to show up with a completion etc.
> + return IIO_VAL_INT;
> + case IIO_ANGL_VEL:
> + *val = data->sc->last_gyro[chan->scan_index];
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
> + case IIO_CHAN_INFO_SCALE:
> + switch (chan->type) {
If the scale really is 1 then don't export it. Note the units would
have to be in m/s^2 which seems unlikely though. I'm guessing this
is a placeholder..
> + case IIO_ACCEL:
> + *val = 1;
> + return IIO_VAL_INT;
> + case IIO_ANGL_VEL:
> + *val = 1;
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
> + case IIO_CHAN_INFO_OFFSET:
> + switch (chan->type) {
> + case IIO_ACCEL:
Again, some unlikely values given after application of offset and scale
the raw values are supposed to be in m/s^2 or radians/s
> + *val = 512;
> + return IIO_VAL_INT;
> + case IIO_ANGL_VEL:
> + *val = 512;
> + return IIO_VAL_INT;
> + default:
> + return -EINVAL;
> + }
> + }
> +
> + return -EINVAL;
> +}
> +
> +#define SONY_ACC_CHANNEL(_axis) { \
> + .type = IIO_ACCEL, \
> + .modified = 1, \
> + .channel2 = IIO_MOD_##_axis, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_OFFSET), \
> + .scan_index = AXIS_##_axis, \
> +}
> +
> +#define SONY_GYRO_CHANNEL(_axis) { \
> + .type = IIO_ANGL_VEL, \
> + .modified = 1, \
> + .channel2 = IIO_MOD_##_axis, \
> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
> + .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_SCALE) | \
> + BIT(IIO_CHAN_INFO_OFFSET), \
> + .scan_index = AXIS_##_axis, \
> +}
> +
> +static const struct iio_chan_spec sony_sixaxis_channels[] = {
> + SONY_ACC_CHANNEL(X),
> + SONY_ACC_CHANNEL(Y),
> + SONY_ACC_CHANNEL(Z),
No gyro channels yet?
Just to note, if the gyro frequency etc is different from the accelerometer
(pretty common) then you'll want to register two IIO devices rather than
just the one so that the control and buffers are separate.
> +};
> +
> +static const struct iio_info sony_iio_info = {
> + .read_raw = &sony_iio_read_raw,
> + .driver_module = THIS_MODULE,
> +};
> +
> +static int sony_iio_probe(struct sony_sc *sc)
> +{
> + struct hid_device *hdev = sc->hdev;
> + struct iio_dev *indio_dev;
> + struct sony_iio *data;
> + int ret;
> +
> + indio_dev = iio_device_alloc(sizeof(*data));
> + if (!indio_dev)
> + return -ENOMEM;
> +
> + sc->indio_dev = indio_dev;
> + data = iio_priv(indio_dev);
> + data->sc = sc;
> +
> + indio_dev->dev.parent = &hdev->dev;
> + indio_dev->name = dev_name(&hdev->dev);
> + indio_dev->modes = INDIO_DIRECT_MODE;
> + indio_dev->info = &sony_iio_info;
> + indio_dev->channels = sony_sixaxis_channels;
> + indio_dev->num_channels = 3;
I'd use array_size for this to avoid accidental bugs if the
number of elements changes in future.
> +
> + ret = iio_device_register(indio_dev);
> + if (ret < 0) {
> + hid_err(hdev, "Unable to register iio device\n");
> + goto error_iio_probe;
> + }
> + return 0;
> +
> +error_iio_probe:
> + kfree(indio_dev);
> + sc->indio_dev = NULL;
> + return ret;
> +}
> +
> +static void sony_iio_remove(struct sony_sc *sc)
> +{
> + if (!sc->indio_dev)
> + return;
> +
> + iio_device_unregister(sc->indio_dev);
> + kfree(sc->indio_dev);
> + sc->indio_dev = NULL;
> +}
> +#endif
> +
> /*
> * If a controller is plugged in via USB while already connected via Bluetooth
> * it will show up as two devices. A global list of connected controllers and
> @@ -2073,6 +2228,15 @@ static int sony_probe(struct hid_device *hdev, const struct hid_device_id *id)
> }
> }
>
> +#if IS_BUILTIN(CONFIG_IIO) || \
> + (IS_MODULE(CONFIG_IIO) && IS_MODULE(CONFIG_HID_SONY))
> + if (sc->quirks & SONY_IIO_SUPPORT) {
> + ret = sony_iio_probe(sc);
> + if (ret < 0)
> + goto err_stop;
> + }
> +#endif
> +
> if (sc->quirks & SONY_FF_SUPPORT) {
> ret = sony_init_ff(sc);
> if (ret < 0)
> @@ -2087,6 +2251,11 @@ err_stop:
> sony_leds_remove(sc);
> if (sc->quirks & SONY_BATTERY_SUPPORT)
> sony_battery_remove(sc);
> +#if IS_BUILTIN(CONFIG_IIO) || \
> + (IS_MODULE(CONFIG_IIO) && IS_MODULE(CONFIG_HID_SONY))
> + if (sc->quirks & SONY_IIO_SUPPORT)
> + sony_iio_remove(sc);
> +#endif
> sony_cancel_work_sync(sc);
> kfree(sc->output_report_dmabuf);
> sony_remove_dev_list(sc);
> @@ -2107,6 +2276,12 @@ static void sony_remove(struct hid_device *hdev)
> sony_battery_remove(sc);
> }
>
> +#if IS_BUILTIN(CONFIG_IIO) || \
> + (IS_MODULE(CONFIG_IIO) && IS_MODULE(CONFIG_HID_SONY))
> + if (sc->quirks & SONY_IIO_SUPPORT)
> + sony_iio_remove(sc);
> +#endif
> +
> sony_cancel_work_sync(sc);
>
> kfree(sc->output_report_dmabuf);
>
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