From 43b7029f475e7497da1de1f4a1742241812bf266 Mon Sep 17 00:00:00 2001
From: Hans de Goede <hdegoede@redhat.com>
Date: Sun, 20 Oct 2019 23:47:18 +0200
Subject: HID: i2c-hid: Send power-on command after reset

Before commit 67b18dfb8cfc ("HID: i2c-hid: Remove runtime power
management"), any i2c-hid touchscreens would typically be runtime-suspended
between the driver loading and Xorg or a Wayland compositor opening it,
causing it to be resumed again. This means that before this change,
we would call i2c_hid_set_power(OFF), i2c_hid_set_power(ON) before the
graphical session would start listening to the touchscreen.

It turns out that at least some SIS touchscreens, such as the one found
on the Asus T100HA, need a power-on command after reset, otherwise they
will not send any events.

Fixes: 67b18dfb8cfc ("HID: i2c-hid: Remove runtime power management")
Cc: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
---
 drivers/hid/i2c-hid/i2c-hid-core.c | 4 ++++
 1 file changed, 4 insertions(+)

(limited to 'drivers/hid')

diff --git a/drivers/hid/i2c-hid/i2c-hid-core.c b/drivers/hid/i2c-hid/i2c-hid-core.c
index d9c55e30f986..04c088131e04 100644
--- a/drivers/hid/i2c-hid/i2c-hid-core.c
+++ b/drivers/hid/i2c-hid/i2c-hid-core.c
@@ -447,8 +447,12 @@ static int i2c_hid_hwreset(struct i2c_client *client)
 	if (ret) {
 		dev_err(&client->dev, "failed to reset device.\n");
 		i2c_hid_set_power(client, I2C_HID_PWR_SLEEP);
+		goto out_unlock;
 	}
 
+	/* At least some SIS devices need this after reset */
+	ret = i2c_hid_set_power(client, I2C_HID_PWR_ON);
+
 out_unlock:
 	mutex_unlock(&ihid->reset_lock);
 	return ret;
-- 
cgit v1.2.3-58-ga151


From ff479731c3859609530416a18ddb3db5db019b66 Mon Sep 17 00:00:00 2001
From: Jason Gerecke <killertofu@gmail.com>
Date: Wed, 6 Nov 2019 11:59:46 -0800
Subject: HID: wacom: generic: Treat serial number and related fields as
 unsigned

The HID descriptors for most Wacom devices oddly declare the serial
number and other related fields as signed integers. When these numbers
are ingested by the HID subsystem, they are automatically sign-extended
into 32-bit integers. We treat the fields as unsigned elsewhere in the
kernel and userspace, however, so this sign-extension causes problems.
In particular, the sign-extended tool ID sent to userspace as ABS_MISC
does not properly match unsigned IDs used by xf86-input-wacom and libwacom.

We introduce a function 'wacom_s32tou' that can undo the automatic sign
extension performed by 'hid_snto32'. We call this function when processing
the serial number and related fields to ensure that we are dealing with
and reporting the unsigned form. We opt to use this method rather than
adding a descriptor fixup in 'wacom_hid_usage_quirk' since it should be
more robust in the face of future devices.

Ref: https://github.com/linuxwacom/input-wacom/issues/134
Fixes: f85c9dc678 ("HID: wacom: generic: Support tool ID and additional tool types")
CC: <stable@vger.kernel.org> # v4.10+
Signed-off-by: Jason Gerecke <jason.gerecke@wacom.com>
Reviewed-by: Aaron Armstrong Skomra <aaron.skomra@wacom.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
---
 drivers/hid/wacom.h     | 15 +++++++++++++++
 drivers/hid/wacom_wac.c | 10 ++++++----
 2 files changed, 21 insertions(+), 4 deletions(-)

(limited to 'drivers/hid')

diff --git a/drivers/hid/wacom.h b/drivers/hid/wacom.h
index 4a7f8d363220..203d27d198b8 100644
--- a/drivers/hid/wacom.h
+++ b/drivers/hid/wacom.h
@@ -202,6 +202,21 @@ static inline void wacom_schedule_work(struct wacom_wac *wacom_wac,
 	}
 }
 
+/*
+ * Convert a signed 32-bit integer to an unsigned n-bit integer. Undoes
+ * the normally-helpful work of 'hid_snto32' for fields that use signed
+ * ranges for questionable reasons.
+ */
+static inline __u32 wacom_s32tou(s32 value, __u8 n)
+{
+	switch (n) {
+	case 8:  return ((__u8)value);
+	case 16: return ((__u16)value);
+	case 32: return ((__u32)value);
+	}
+	return value & (1 << (n - 1)) ? value & (~(~0U << n)) : value;
+}
+
 extern const struct hid_device_id wacom_ids[];
 
 void wacom_wac_irq(struct wacom_wac *wacom_wac, size_t len);
diff --git a/drivers/hid/wacom_wac.c b/drivers/hid/wacom_wac.c
index 2b0a5b8ca6e6..ccb74529bc78 100644
--- a/drivers/hid/wacom_wac.c
+++ b/drivers/hid/wacom_wac.c
@@ -2303,7 +2303,7 @@ static void wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field
 	case HID_DG_TOOLSERIALNUMBER:
 		if (value) {
 			wacom_wac->serial[0] = (wacom_wac->serial[0] & ~0xFFFFFFFFULL);
-			wacom_wac->serial[0] |= (__u32)value;
+			wacom_wac->serial[0] |= wacom_s32tou(value, field->report_size);
 		}
 		return;
 	case HID_DG_TWIST:
@@ -2319,15 +2319,17 @@ static void wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field
 		return;
 	case WACOM_HID_WD_SERIALHI:
 		if (value) {
+			__u32 raw_value = wacom_s32tou(value, field->report_size);
+
 			wacom_wac->serial[0] = (wacom_wac->serial[0] & 0xFFFFFFFF);
-			wacom_wac->serial[0] |= ((__u64)value) << 32;
+			wacom_wac->serial[0] |= ((__u64)raw_value) << 32;
 			/*
 			 * Non-USI EMR devices may contain additional tool type
 			 * information here. See WACOM_HID_WD_TOOLTYPE case for
 			 * more details.
 			 */
 			if (value >> 20 == 1) {
-				wacom_wac->id[0] |= value & 0xFFFFF;
+				wacom_wac->id[0] |= raw_value & 0xFFFFF;
 			}
 		}
 		return;
@@ -2339,7 +2341,7 @@ static void wacom_wac_pen_event(struct hid_device *hdev, struct hid_field *field
 		 * bitwise OR so the complete value can be built
 		 * up over time :(
 		 */
-		wacom_wac->id[0] |= value;
+		wacom_wac->id[0] |= wacom_s32tou(value, field->report_size);
 		return;
 	case WACOM_HID_WD_OFFSETLEFT:
 		if (features->offset_left && value != features->offset_left)
-- 
cgit v1.2.3-58-ga151