HID: pidff: Add support for AXES_ENABLE field

AXES_ENABLE can be used in place of DIRECTION_ENABLE to indicate, which
FFB-enabled axes will be affected by a given effect. EFFECT_DIRECTION
enables all and uses the first direction only while AXES_ENABLE is a
bitmask and bit indexes are the same as the defined GD usages in the
EFFECT_DIRECTION array. Each axis can have it's own direction in this
case.

Search for AXES_ENABLE, set AXES_ENABLE for all axes if DIRECTION_ENABLE
is not used.

Search for specific axes in the direction array. Save their indexes. This
let us know what axes are actually available on the device and which bit
in the AXES_ENABLE field corresponds to which axis.

Signed-off-by: Tomasz Pakuła <tomasz.pakula.oficjalny@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.com>

Author: Lawstorant

drivers/hid/usbhid/hid-pidff.c

@@ -51,6 +51,7 @@ static const u8 pidff_reports[] = {
 
 /* PID special fields */
 #define PID_EFFECT_TYPE			0x25
+#define PID_AXES_ENABLE			0x55
 #define PID_DIRECTION			0x57
 #define PID_EFFECT_OPERATION_ARRAY	0x78
 #define PID_BLOCK_LOAD_STATUS		0x8b
@@ -150,6 +151,31 @@ static const u8 pidff_effect_operation_status[] = { 0x79, 0x7b };
 /* Polar direction 90 degrees (East) */
 #define PIDFF_FIXED_WHEEL_DIRECTION	0x4000
 
+/* AXES_ENABLE and DIRECTION axes */
+enum pid_axes {
+	PID_AXIS_X,
+	PID_AXIS_Y,
+	PID_AXIS_Z,
+	PID_AXIS_RX,
+	PID_AXIS_RY,
+	PID_AXIS_RZ,
+	PID_AXIS_SLIDER,
+	PID_AXIS_DIAL,
+	PID_AXIS_WHEEL,
+	PID_AXES_COUNT,
+};
+static const u8 pidff_direction_axis[] = {
+	HID_USAGE & HID_GD_X,
+	HID_USAGE & HID_GD_Y,
+	HID_USAGE & HID_GD_Z,
+	HID_USAGE & HID_GD_RX,
+	HID_USAGE & HID_GD_RY,
+	HID_USAGE & HID_GD_RZ,
+	HID_USAGE & HID_GD_SLIDER,
+	HID_USAGE & HID_GD_DIAL,
+	HID_USAGE & HID_GD_WHEEL,
+};
+
 struct pidff_usage {
 	struct hid_field *field;
 	s32 *value;
@@ -184,6 +210,7 @@ struct pidff_device {
 	/* Special fields in set_effect */
 	struct hid_field *set_effect_type;
 	struct hid_field *effect_direction;
+	struct hid_field *axes_enable;
 
 	/* Special field in device_control */
 	struct hid_field *device_control;
@@ -198,11 +225,13 @@ struct pidff_device {
 	int type_id[ARRAY_SIZE(pidff_effect_types)];
 	int status_id[ARRAY_SIZE(pidff_block_load_status)];
 	int operation_id[ARRAY_SIZE(pidff_effect_operation_status)];
+	int direction_axis_id[ARRAY_SIZE(pidff_direction_axis)];
 
 	int pid_id[PID_EFFECTS_MAX];
 
 	u32 quirks;
 	u8 effect_count;
+	u8 axis_count;
 };
 
 static int pidff_is_effect_conditional(struct ff_effect *effect)
@@ -306,14 +335,37 @@ static void pidff_set_effect_direction(struct pidff_device *pidff,
 				       struct ff_effect *effect)
 {
 	u16 direction = effect->direction;
+	int direction_enable = 1;
 
 	/* Use fixed direction if needed */
 	if (pidff->quirks & HID_PIDFF_QUIRK_FIX_CONDITIONAL_DIRECTION &&
 	    pidff_is_effect_conditional(effect))
 		direction = PIDFF_FIXED_WHEEL_DIRECTION;
 
+	pidff->set_effect[PID_DIRECTION_ENABLE].value[0] = direction_enable;
 	pidff->effect_direction->value[0] =
 		pidff_rescale(direction, U16_MAX, pidff->effect_direction);
+
+	if (direction_enable)
+		return;
+
+	/*
+	 * For use with improved FFB API
+	 * We want to read the selected axes and their direction from the effect
+	 * struct and only enable those. For now, enable all axes.
+	 *
+	 */
+	for (int i = 0; i < PID_AXES_COUNT; i++) {
+		/* HID index starts with 1 */
+		int index = pidff->direction_axis_id[i] - 1;
+
+		if (index < 0)
+			continue;
+
+		pidff->axes_enable->value[index] = 1;
+		pidff->effect_direction->value[index] = pidff_rescale(
+			direction, U16_MAX, pidff->effect_direction);
+	}
 }
 
 /*
@@ -411,7 +463,6 @@ static void pidff_set_effect_report(struct pidff_device *pidff,
 			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;
 
 	pidff_set_effect_direction(pidff, effect);
 
@@ -1122,12 +1173,13 @@ static struct hid_field *pidff_find_special_field(struct hid_report *report,
  * Fill a pidff->*_id struct table
  */
 static int pidff_find_special_keys(int *keys, struct hid_field *fld,
-				   const u8 *usagetable, int count)
+				   const u8 *usagetable, int count,
+				   unsigned int usage_page)
 {
 	int found = 0;
 
 	for (int i = 0; i < count; i++) {
-		keys[i] = pidff_find_usage(fld, HID_UP_PID | usagetable[i]) + 1;
+		keys[i] = pidff_find_usage(fld, usage_page | usagetable[i]) + 1;
 		if (keys[i])
 			found++;
 	}
@@ -1136,7 +1188,11 @@ static int pidff_find_special_keys(int *keys, struct hid_field *fld,
 
 #define PIDFF_FIND_SPECIAL_KEYS(keys, field, name) \
 	pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
-		ARRAY_SIZE(pidff_ ## name))
+		ARRAY_SIZE(pidff_ ## name), HID_UP_PID)
+
+#define PIDFF_FIND_GENERAL_DESKTOP(keys, field, name) \
+	pidff_find_special_keys(pidff->keys, pidff->field, pidff_ ## name, \
+		ARRAY_SIZE(pidff_ ## name), HID_UP_GENDESK)
 
 /*
  * Find and check the special fields
@@ -1151,6 +1207,9 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 	pidff->set_effect_type =
 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
 					 PID_EFFECT_TYPE, 1);
+	pidff->axes_enable =
+		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
+					 PID_AXES_ENABLE, 0);
 	pidff->effect_direction =
 		pidff_find_special_field(pidff->reports[PID_SET_EFFECT],
 					 PID_DIRECTION, 0);
@@ -1216,6 +1275,30 @@ static int pidff_find_special_fields(struct pidff_device *pidff)
 		return -1;
 	}
 
+	if (!pidff->axes_enable)
+		hid_info(pidff->hid, "axes enable field not found!\n");
+	else
+		hid_dbg(pidff->hid, "axes enable report count: %u\n",
+			pidff->axes_enable->report_count);
+
+	uint found = PIDFF_FIND_GENERAL_DESKTOP(direction_axis_id, axes_enable,
+						direction_axis);
+
+	pidff->axis_count = found;
+	hid_dbg(pidff->hid, "found direction axes: %u", found);
+
+	for (int i = 0; i < sizeof(pidff_direction_axis); i++) {
+		if (!pidff->direction_axis_id[i])
+			continue;
+
+		hid_dbg(pidff->hid, "axis %d, usage: 0x%04x, index: %d", i + 1,
+			pidff_direction_axis[i], pidff->direction_axis_id[i]);
+	}
+
+	if (pidff->axes_enable && found != pidff->axes_enable->report_count)
+		hid_warn(pidff->hid, "axes_enable: %u != direction axes: %u",
+			 pidff->axes_enable->report_count, found);
+
 	return 0;
 }