[PATCH v3 05/12] HID: asus: add joysticks inner and outer range configuration

[Denis Benato <denis.benato@linux.dev>]

ROG Ally devices supports configuring joysticks inner and outer range:
add sysfs attributes to allow userspace modifying the sensitivity
of those controllers.

Assisted-by: opencode:glm-5.2
Signed-off-by: Denis Benato <denis.benato@linux.dev>
Signed-off-by: Luke Jones <luke@ljones.dev>
---
 drivers/hid/hid-asus.c | 396 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 396 insertions(+)

diff --git a/drivers/hid/hid-asus.c b/drivers/hid/hid-asus.c
index dc1a4fb6c9e9..13a1f9e44661 100644
--- a/drivers/hid/hid-asus.c
+++ b/drivers/hid/hid-asus.c
@@ -973,6 +973,351 @@ static struct device_attribute dev_attr_right_vibration_intensity =
 static struct device_attribute dev_attr_right_vibration_intensity_range =
 	__ATTR(intensity_range, 0444, right_vibration_intensity_range_show, NULL);
 
+/**
+ * ally_set_joystick_thresholds() - Generic function to set joystick ranges
+ * @ally: ally handheld structure
+ * @hdev: HID device
+ * @cfg: ally config
+ * @left_it: inner threshold (deadzone) of the left stick (0-50)
+ * @left_ot: outer threshold of the left stick (70-100)
+ * @right_it: inner threshold (deadzone) of the right stick (0-50)
+ * @right_ot: outer threshold of the right stick (70-100)
+ *
+ * This function sends the command to set both inner and outer threshold
+ * for the left and right joysticks.
+ *
+ * Return: 0 on success, negative errno on failure
+ */
+static int ally_set_joystick_thresholds(struct ally_handheld *ally,
+					struct hid_device *hdev, struct ally_config *cfg,
+					u8 left_it, u8 left_ot, u8 right_it, u8 right_ot)
+{
+	const u8 payload[] = { left_it, left_ot, right_it, right_ot };
+	int ret;
+
+	u8 *buf __free(kfree) = ally_alloc_cmd(CMD_SET_JOYSTICK_DEADZONE, payload, sizeof(payload));
+	if (!buf)
+		return -ENOMEM;
+
+	ret = ally_gamepad_send_packet(ally, hdev, buf, ROG_ALLY_REPORT_SIZE);
+	if (ret < 0) {
+		hid_err(hdev, "Failed to set joystick ranges: %d\n", ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static ssize_t left_joystick_inner_threshold_show(struct device *dev, struct device_attribute *attr,
+						  char *buf)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	return sysfs_emit(buf, "%u\n", cfg->left_deadzone);
+}
+
+static ssize_t left_joystick_inner_threshold_store(struct device *dev,
+						   struct device_attribute *attr,
+						   const char *buf, size_t count)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+	u8 value;
+	int ret;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	ret = kstrtou8(buf, 10, &value);
+	if (ret || value > 50)
+		return -EINVAL;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	ret = ally_set_joystick_thresholds(ally, hdev, cfg,
+					   value,
+					   cfg->left_outer_threshold,
+					   cfg->right_deadzone,
+					   cfg->right_outer_threshold);
+	if (ret)
+		return ret;
+
+	cfg->left_deadzone = value;
+
+	return count;
+}
+
+static ssize_t left_joystick_inner_threshold_range_show(struct device *dev,
+							struct device_attribute *attr,
+							char *buf)
+{
+	return sysfs_emit(buf, "0 50\n");
+}
+
+static ssize_t left_joystick_outer_threshold_show(struct device *dev, struct device_attribute *attr,
+						  char *buf)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	return sysfs_emit(buf, "%u\n", cfg->left_outer_threshold);
+}
+
+static ssize_t left_joystick_outer_threshold_store(struct device *dev,
+						   struct device_attribute *attr,
+						   const char *buf, size_t count)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+	u8 value;
+	int ret;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	ret = kstrtou8(buf, 10, &value);
+	if (ret || value < 70 || value > 100)
+		return -EINVAL;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	ret = ally_set_joystick_thresholds(ally, hdev, cfg,
+					   cfg->left_deadzone,
+					   value,
+					   cfg->right_deadzone,
+					   cfg->right_outer_threshold);
+	if (ret)
+		return ret;
+
+	cfg->left_outer_threshold = value;
+
+	return count;
+}
+
+static ssize_t left_joystick_outer_threshold_range_show(struct device *dev,
+							struct device_attribute *attr,
+							char *buf)
+{
+	return sysfs_emit(buf, "70 100\n");
+}
+
+static ssize_t right_joystick_inner_threshold_show(struct device *dev,
+						   struct device_attribute *attr,
+						   char *buf)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	return sysfs_emit(buf, "%u\n", cfg->right_deadzone);
+}
+
+static ssize_t right_joystick_inner_threshold_store(struct device *dev,
+						    struct device_attribute *attr,
+						    const char *buf, size_t count)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+	u8 value;
+	int ret;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	ret = kstrtou8(buf, 10, &value);
+	if (ret || value > 50)
+		return -EINVAL;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	ret = ally_set_joystick_thresholds(ally, hdev, cfg,
+					   cfg->left_deadzone,
+					   cfg->left_outer_threshold,
+					   value,
+					   cfg->right_outer_threshold);
+	if (ret)
+		return ret;
+
+	cfg->right_deadzone = value;
+
+	return count;
+}
+
+static ssize_t right_joystick_inner_threshold_range_show(struct device *dev,
+							 struct device_attribute *attr,
+							 char *buf)
+{
+	return sysfs_emit(buf, "0 50\n");
+}
+
+static ssize_t right_joystick_outer_threshold_show(struct device *dev,
+						   struct device_attribute *attr,
+						   char *buf)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	return sysfs_emit(buf, "%u\n", cfg->right_outer_threshold);
+}
+
+static ssize_t right_joystick_outer_threshold_store(struct device *dev,
+						    struct device_attribute *attr,
+						    const char *buf, size_t count)
+{
+	struct hid_device *hdev = to_hid_device(dev);
+	struct asus_drvdata *drvdata = hid_get_drvdata(hdev);
+	struct ally_handheld *const ally = drvdata->rog_ally;
+	struct ally_config *cfg;
+	u8 value;
+	int ret;
+
+	if (!ally)
+		return -ENODEV;
+
+	cfg = ally_get_config(ally);
+	if (!cfg)
+		return -ENODEV;
+
+	ret = kstrtou8(buf, 10, &value);
+	if (ret || value < 70 || value > 100)
+		return -EINVAL;
+
+	guard(mutex)(&cfg->config_mutex);
+
+	if (!cfg->user_cal_support)
+		return -EOPNOTSUPP;
+
+	ret = ally_set_joystick_thresholds(ally, hdev, cfg,
+					   cfg->left_deadzone,
+					   cfg->left_outer_threshold,
+					   cfg->right_deadzone,
+					   value);
+	if (ret)
+		return ret;
+
+	cfg->right_outer_threshold = value;
+
+	return count;
+}
+
+static ssize_t right_joystick_outer_threshold_range_show(struct device *dev,
+							 struct device_attribute *attr,
+							 char *buf)
+{
+	return sysfs_emit(buf, "70 100\n");
+}
+
+static struct device_attribute dev_attr_left_joystick_inner_threshold =
+	__ATTR(inner_threshold, 0644, left_joystick_inner_threshold_show,
+	       left_joystick_inner_threshold_store);
+
+static struct device_attribute dev_attr_left_joystick_inner_threshold_range =
+	__ATTR(inner_threshold_range, 0444, left_joystick_inner_threshold_range_show, NULL);
+
+static struct device_attribute dev_attr_left_joystick_outer_threshold =
+	__ATTR(outer_threshold, 0644, left_joystick_outer_threshold_show,
+	       left_joystick_outer_threshold_store);
+
+static struct device_attribute dev_attr_left_joystick_outer_threshold_range =
+	__ATTR(outer_threshold_range, 0444, left_joystick_outer_threshold_range_show, NULL);
+
+static struct device_attribute dev_attr_right_joystick_inner_threshold =
+	__ATTR(inner_threshold, 0644, right_joystick_inner_threshold_show,
+	       right_joystick_inner_threshold_store);
+
+static struct device_attribute dev_attr_right_joystick_inner_threshold_range =
+	__ATTR(inner_threshold_range, 0444, right_joystick_inner_threshold_range_show, NULL);
+
+static struct device_attribute dev_attr_right_joystick_outer_threshold =
+	__ATTR(outer_threshold, 0644, right_joystick_outer_threshold_show,
+	       right_joystick_outer_threshold_store);
+
+static struct device_attribute dev_attr_right_joystick_outer_threshold_range =
+	__ATTR(outer_threshold_range, 0444, right_joystick_outer_threshold_range_show, NULL);
+
 static struct attribute *ally_config_attrs[] = {
 	&dev_attr_xbox_controller.attr,
 	NULL
@@ -990,6 +1335,22 @@ static struct attribute *ally_right_vibration_attrs[] = {
 	NULL
 };
 
+static struct attribute *left_joystick_axis_attrs[] = {
+	&dev_attr_left_joystick_inner_threshold.attr,
+	&dev_attr_left_joystick_outer_threshold.attr,
+	&dev_attr_left_joystick_inner_threshold_range.attr,
+	&dev_attr_left_joystick_outer_threshold_range.attr,
+	NULL
+};
+
+static struct attribute *right_joystick_axis_attrs[] = {
+	&dev_attr_right_joystick_inner_threshold.attr,
+	&dev_attr_right_joystick_outer_threshold.attr,
+	&dev_attr_right_joystick_inner_threshold_range.attr,
+	&dev_attr_right_joystick_outer_threshold_range.attr,
+	NULL
+};
+
 static const struct attribute_group ally_attr_groups[] = {
 	{
 		.attrs = ally_config_attrs,
@@ -1004,6 +1365,28 @@ static const struct attribute_group ally_attr_groups[] = {
 	},
 };
 
+/*
+ * The joystick range calibration attributes are tied to the
+ * user-calibration capability: their sysfs groups are registered only
+ * when the device supports configuring those parameters, and the show
+ * and store callbacks reject accesses with -EOPNOTSUPP regardless, in
+ * case the groups are registered for another supported feature.
+ */
+static const struct attribute_group ally_left_joystick_axis_group = {
+	.name = "left_joystick_axis",
+	.attrs = left_joystick_axis_attrs,
+};
+
+static const struct attribute_group ally_right_joystick_axis_group = {
+	.name = "right_joystick_axis",
+	.attrs = right_joystick_axis_attrs,
+};
+
+static const struct attribute_group *const ally_cal_attr_groups[] = {
+	&ally_left_joystick_axis_group,
+	&ally_right_joystick_axis_group,
+};
+
 /**
  * ally_config_create() - Initialize configuration and create sysfs entries
  * @hdev: HID device
@@ -1037,6 +1420,19 @@ static struct ally_config *ally_config_create(struct hid_device *hdev, struct al
 		}
 	}
 
+	/* Skip the calibration groups when the capability is missing. */
+	if (cfg->user_cal_support) {
+		for (sysfs_i = 0; sysfs_i < ARRAY_SIZE(ally_cal_attr_groups); sysfs_i++) {
+			ret = devm_device_add_group(&hdev->dev,
+						    ally_cal_attr_groups[sysfs_i]);
+			if (ret < 0) {
+				hid_err(hdev, "Failed to create sysfs group '%s': %d\n",
+					ally_cal_attr_groups[sysfs_i]->name, ret);
+				goto ally_config_create_sysfs_err;
+			}
+		}
+	}
+
 	cfg->gamepad_mode = 0x01;
 	cfg->left_deadzone = 10;
 	cfg->left_outer_threshold = 90;
-- 
2.47.3