PID devices can use different exponents for time fields, while Linux
Force Feedback API only supports miliseconds.
Read the exponent of a given time field and scale its value accordingly.
Changes in v7:
- Rescale all time fields, not only period
Co-developed-by: Makarenko Oleg <oleg@xxxxxxxxxxxx>
Signed-off-by: Makarenko Oleg <oleg@xxxxxxxxxxxx>
Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@xxxxxxxxx>
Reviewed-by: Michał Kopeć <michal@nozomi.space>
Tested-by: Cristóferson Bueno <cbueno81@xxxxxxxxx>
---
drivers/hid/usbhid/hid-pidff.c | 69 ++++++++++++++++++++++++++--------
1 file changed, 54 insertions(+), 15 deletions(-)
diff --git a/drivers/hid/usbhid/hid-pidff.c b/drivers/hid/usbhid/hid-pidff.c
index fbb79179e02b..6fcced6348ec 100644
--- a/drivers/hid/usbhid/hid-pidff.c
+++ b/drivers/hid/usbhid/hid-pidff.c
@@ -22,6 +22,9 @@
#define PID_EFFECTS_MAX 64
#define PID_INFINITE 0xffff
+/* Linux Force Feedback API uses miliseconds as time unit */
+#define FF_TIME_EXPONENT -3
+
/* Report usage table used to put reports into an array */
#define PID_SET_EFFECT 0
@@ -231,6 +234,24 @@ static int pidff_rescale_signed(int i, struct hid_field *field)
field->logical_minimum / -0x8000;
}
+/*
+ * Scale time value from Linux default (ms) to field units
+ */
+static u32 pidff_rescale_time(u16 time, struct hid_field *field)
+{
+ u32 scaled_time = time;
+ int exponent = field->unit_exponent;
+ pr_debug("time field exponent: %d\n", exponent);
+
+ for (;exponent < FF_TIME_EXPONENT; exponent++)
+ scaled_time *= 10;
+ for (;exponent > FF_TIME_EXPONENT; exponent--)
+ scaled_time /= 10;
+
+ pr_debug("time calculated from %d to %d\n", time, scaled_time);
+ return scaled_time;
+}
+
static void pidff_set(struct pidff_usage *usage, u16 value)
{
usage->value[0] = pidff_rescale(value, 0xffff, usage->field);
@@ -252,6 +273,27 @@ static void pidff_set_signed(struct pidff_usage *usage, s16 value)
pr_debug("calculated from %d to %d\n", value, usage->value[0]);
}
+static void pidff_set_time(struct pidff_usage *usage, u16 time)
+{
+ u32 modified_time = pidff_rescale_time(time, usage->field);
+ usage->value[0] = pidff_clamp(modified_time, usage->field);
+}
+
+static void pidff_set_duration(struct pidff_usage *usage, u16 duration)
+{
+ /* Convert infinite length from Linux API (0)
+ to PID standard (NULL) if needed */
+ if (duration == 0)
+ duration = PID_INFINITE;
+
+ if (duration == PID_INFINITE) {
+ usage->value[0] = PID_INFINITE;
+ return;
+ }
+
+ pidff_set_time(usage, duration);
+}
+
/*
* Send envelope report to the device
*/
@@ -270,8 +312,10 @@ static void pidff_set_envelope_report(struct pidff_device *pidff,
0x7fff ? 0x7fff : envelope->fade_level, 0x7fff,
pidff->set_envelope[PID_FADE_LEVEL].field);
- pidff->set_envelope[PID_ATTACK_TIME].value[0] = envelope->attack_length;
- pidff->set_envelope[PID_FADE_TIME].value[0] = envelope->fade_length;
+ pidff_set_time(&pidff->set_envelope[PID_ATTACK_TIME],
+ envelope->attack_length);
+ pidff_set_time(&pidff->set_envelope[PID_FADE_TIME],
+ envelope->attack_length);
hid_dbg(pidff->hid, "attack %u => %d\n",
envelope->attack_level,
@@ -340,14 +384,12 @@ static void pidff_set_effect_report(struct pidff_device *pidff,
pidff->set_effect_type->value[0] =
pidff->create_new_effect_type->value[0];
- /* Convert infinite length from Linux API (0)
- to PID standard (NULL) if needed */
- pidff->set_effect[PID_DURATION].value[0] =
- effect->replay.length == 0 ? PID_INFINITE : effect->replay.length;
+ pidff_set_duration(&pidff->set_effect[PID_DURATION],
+ effect->replay.length);
pidff->set_effect[PID_TRIGGER_BUTTON].value[0] = effect->trigger.button;
- pidff->set_effect[PID_TRIGGER_REPEAT_INT].value[0] =
- effect->trigger.interval;
+ pidff_set_time(&pidff->set_effect[PID_TRIGGER_REPEAT_INT],
+ effect->trigger.interval);
pidff->set_effect[PID_GAIN].value[0] =
pidff->set_effect[PID_GAIN].field->logical_maximum;
pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = 1;
@@ -360,7 +402,8 @@ static void pidff_set_effect_report(struct pidff_device *pidff,
/* Omit setting delay field if it's missing */
if (!(pidff->quirks & HID_PIDFF_QUIRK_MISSING_DELAY))
- pidff->set_effect[PID_START_DELAY].value[0] = effect->replay.delay;
+ pidff_set_time(&pidff->set_effect[PID_START_DELAY],
+ effect->replay.delay);
hid_hw_request(pidff->hid, pidff->reports[PID_SET_EFFECT],
HID_REQ_SET_REPORT);
@@ -392,15 +435,11 @@ static void pidff_set_periodic_report(struct pidff_device *pidff,
pidff_set_signed(&pidff->set_periodic[PID_OFFSET],
effect->u.periodic.offset);
pidff_set(&pidff->set_periodic[PID_PHASE], effect->u.periodic.phase);
-
- /* Clamp period to ensure the device can play the effect */
- pidff->set_periodic[PID_PERIOD].value[0] =
- pidff_clamp(effect->u.periodic.period,
- pidff->set_periodic[PID_PERIOD].field);
+ pidff_set_time(&pidff->set_periodic[PID_PERIOD],
+ effect->u.periodic.period);
hid_hw_request(pidff->hid, pidff->reports[PID_SET_PERIODIC],
HID_REQ_SET_REPORT);
-
}
/*
--
2.48.1
