Dnia 2010-03-18, czw o godzinie 15:37 +0000, Bastien Nocera pisze:
> On Thu, 2010-03-18 at 15:26 +0000, Przemo Firszt wrote:
>
> > + unsigned char speed;
>
> Could you add some comments as to what values represent what speed?
I changed name from 'speed' to 'high_speed' as per your comment below,
so I think there is no need (unless you think otherwise).
>
> > +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;
> > +
> > + sscanf(buf, "%1d", &new_speed);
>
> You should check the retval of sscanf as well.
Done, see attached patch.
> > + 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);
>
> If there's only 2 speeds available, and it's actually a boolean, I'd
> rather you used a name like "high_speed".
>
> Furthermore, wdata->speed doesn't look like it's initialised.
It is initialised by the very first call of wacom_poke from wacom_probe
function. Can you advise if it's enough?
>
> Did you test whether speed switching works after the device has been
> started up?
Yes, it works like a charm, both ways.
[przemo@pldmachine ~]$ echo 0 > /sys/class/hidraw/hidraw1/device/speed
and lag is gone,
[przemo@pldmachine ~]$ echo 1 > /sys/class/hidraw/hidraw1/device/speed
and "rubber band" effect is back.
Thanks for your comments,
Przemo
>From ec2c13649c3d7188199bfddc06b4211170c28b1c Mon Sep 17 00:00:00 2001
From: Przemo Firszt <przemo@xxxxxxxxx>
Date: Thu, 18 Mar 2010 14:34:34 +0000
Subject: [PATCH 2/2] 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: Przemo Firszt <przemo@xxxxxxxxx>
---
drivers/hid/hid-wacom.c | 40 +++++++++++++++++++++++++++++++++++++++-
1 files changed, 39 insertions(+), 1 deletions(-)
diff --git a/drivers/hid/hid-wacom.c b/drivers/hid/hid-wacom.c
index f9d4939..97ef626 100644
--- a/drivers/hid/hid-wacom.c
+++ b/drivers/hid/hid-wacom.c
@@ -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];
@@ -128,8 +130,10 @@ 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;
+ }
}
/*
@@ -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);
--
1.7.0.1
