Commit 20a3ce7e authored by Przemo Firszt's avatar Przemo Firszt Committed by Jiri Kosina
Browse files

HID: add sysfs speed attribute for wacom bluetooth tablet 



The attribute allows to change reporting speed of tablet from userspace through
sysfs file. The attribute is RW, valid values: 0 is low speed, 1 is high speed.
High speed is the default setting. Using low speed is a workaround if you
experience lag when using the tablet.

Signed-off-by: default avatarPrzemo Firszt <przemo@firszt.eu>
Signed-off-by: default avatarJiri Kosina <jkosina@suse.cz>
parent 06c7c313

drivers/hid/hid-wacom.c

+39 −1
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ 
struct wacom_data {

	__u16 tool;

	unsigned char butstate;

	unsigned char high_speed;

#ifdef CONFIG_HID_WACOM_POWER_SUPPLY

	int battery_capacity;

	struct power_supply battery;
@@ -105,6 +106,7 @@ static int wacom_ac_get_property(struct power_supply *psy, 


static void wacom_poke(struct hid_device *hdev, u8 speed)

{

	struct wacom_data *wdata = hid_get_drvdata(hdev);

	int limit, ret;

	char rep_data[2];
@@ -128,9 +130,11 @@ static void wacom_poke(struct hid_device *hdev, u8 speed) 
					HID_FEATURE_REPORT);

		} while (ret < 0 && limit-- > 0);



		if (ret >= 0)

		if (ret >= 0) {

			wdata->high_speed = speed;

			return;

		}

	}



	/*

	 * Note that if the raw queries fail, it's not a hard failure and it
@@ -141,6 +145,35 @@ static void wacom_poke(struct hid_device *hdev, u8 speed) 
	return;

}



static ssize_t wacom_show_speed(struct device *dev,

				struct device_attribute

				*attr, char *buf)

{

	struct wacom_data *wdata = dev_get_drvdata(dev);



	return snprintf(buf, PAGE_SIZE, "%i\n", wdata->high_speed);

}



static ssize_t wacom_store_speed(struct device *dev,

				struct device_attribute *attr,

				const char *buf, size_t count)

{

	struct hid_device *hdev = container_of(dev, struct hid_device, dev);

	int new_speed;



	if (sscanf(buf, "%1d", &new_speed ) != 1)

		return -EINVAL;



	if (new_speed == 0 || new_speed == 1) {

		wacom_poke(hdev, new_speed);

		return strnlen(buf, PAGE_SIZE);

	} else

		return -EINVAL;

}



static DEVICE_ATTR(speed, S_IRUGO | S_IWUGO,

		wacom_show_speed, wacom_store_speed);



static int wacom_raw_event(struct hid_device *hdev, struct hid_report *report,

		u8 *raw_data, int size)

{
@@ -297,6 +330,11 @@ static int wacom_probe(struct hid_device *hdev, 
		goto err_free;

	}



	ret = device_create_file(&hdev->dev, &dev_attr_speed);

	if (ret)

		dev_warn(&hdev->dev,

			"can't create sysfs speed attribute err: %d\n", ret);



	/* Set Wacom mode 2 with high reporting speed */

	wacom_poke(hdev, 1);

CRA Git | Maintained and supported by SUSTech CRA and CCSE