[PATCH v6 05/19] HID: hid-lenovo-go: Add FPS Mode DPI settings

["Derek J. Clark" <derekjohn.clark@gmail.com>]

Adds attribute that enables selection of the DPI of the optical sensor
when the right handle toggle is set to FPS mode.

Reviewed-by: Mark Pearson <mpearson-lenovo@squebb.ca>
Signed-off-by: Derek J. Clark <derekjohn.clark@gmail.com>
---
v6:
  - Use NULL instead of 0 in mcu_propery_out when there is no data.
---
 drivers/hid/hid-lenovo-go.c | 68 +++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)

diff --git a/drivers/hid/hid-lenovo-go.c b/drivers/hid/hid-lenovo-go.c
index f2a54865cfbb..24f9444c93cd 100644
--- a/drivers/hid/hid-lenovo-go.c
+++ b/drivers/hid/hid-lenovo-go.c
@@ -67,6 +67,7 @@ static struct hid_go_cfg {
 	u32 mcu_version_hardware;
 	u32 mcu_version_product;
 	u32 mcu_version_protocol;
+	u32 mouse_dpi;
 	u8 rgb_en;
 	u8 tp_en;
 	u8 tp_vibration_en;
@@ -220,6 +221,8 @@ static const char *const rumble_mode_text[] = {
 	[RUMBLE_MODE_RPG] = "rpg",
 };
 
+#define FPS_MODE_DPI           0x02
+
 static int hid_go_version_event(struct command_report *cmd_rep)
 {
 	switch (cmd_rep->sub_cmd) {
@@ -427,6 +430,16 @@ static int hid_go_motor_event(struct command_report *cmd_rep)
 	return -EINVAL;
 }
 
+static int hid_go_fps_dpi_event(struct command_report *cmd_rep)
+{
+	if (cmd_rep->sub_cmd != FPS_MODE_DPI)
+		return -EINVAL;
+
+	drvdata.mouse_dpi = get_unaligned_le32(cmd_rep->data);
+
+	return 0;
+}
+
 static int hid_go_set_event_return(struct command_report *cmd_rep)
 {
 	if (cmd_rep->data[0] != 0)
@@ -477,8 +490,12 @@ static int hid_go_raw_event(struct hid_device *hdev, struct hid_report *report,
 		case GET_MOTOR_CFG:
 			ret = hid_go_motor_event(cmd_rep);
 			break;
+		case GET_DPI_CFG:
+			ret = hid_go_fps_dpi_event(cmd_rep);
+			break;
 		case SET_FEATURE_STATUS:
 		case SET_MOTOR_CFG:
+		case SET_DPI_CFG:
 			ret = hid_go_set_event_return(cmd_rep);
 			break;
 		default:
@@ -1016,6 +1033,52 @@ static ssize_t motor_config_options(struct device *dev,
 	return count;
 }
 
+static ssize_t fps_mode_dpi_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+
+{
+	size_t size = 4;
+	u32 value;
+	u8 val[4];
+	int ret;
+
+	ret = kstrtou32(buf, 10, &value);
+	if (ret)
+		return ret;
+
+	if (value != 500 && value != 800 && value != 1200 && value != 1800)
+		return -EINVAL;
+
+	put_unaligned_le32(value, val);
+
+	ret = mcu_property_out(drvdata.hdev, MCU_CONFIG_DATA, SET_DPI_CFG,
+			       FPS_MODE_DPI, UNSPECIFIED, val, size);
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static ssize_t fps_mode_dpi_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	int ret;
+
+	ret = mcu_property_out(drvdata.hdev, MCU_CONFIG_DATA, GET_DPI_CFG,
+			       FPS_MODE_DPI, UNSPECIFIED, NULL, 0);
+	if (ret < 0)
+		return ret;
+
+	return sysfs_emit(buf, "%u\n", drvdata.mouse_dpi);
+}
+
+static ssize_t fps_mode_dpi_index_show(struct device *dev,
+				       struct device_attribute *attr, char *buf)
+{
+	return sysfs_emit(buf, "500 800 1200 1800\n");
+}
+
 #define LEGO_DEVICE_ATTR_RW(_name, _attrname, _dtype, _rtype, _group)         \
 	static ssize_t _name##_store(struct device *dev,                      \
 				     struct device_attribute *attr,           \
@@ -1087,7 +1150,12 @@ LEGO_DEVICE_ATTR_RW(gamepad_rumble_intensity, "rumble_intensity", UNSPECIFIED,
 static DEVICE_ATTR_RO_NAMED(gamepad_rumble_intensity_index,
 			    "rumble_intensity_index");
 
+static DEVICE_ATTR_RW(fps_mode_dpi);
+static DEVICE_ATTR_RO(fps_mode_dpi_index);
+
 static struct attribute *mcu_attrs[] = {
+	&dev_attr_fps_mode_dpi.attr,
+	&dev_attr_fps_mode_dpi_index.attr,
 	&dev_attr_fps_switch_status.attr,
 	&dev_attr_gamepad_mode.attr,
 	&dev_attr_gamepad_mode_index.attr,
-- 
2.53.0