[PATCH 2/4] HID: core: break out hid_find_max_report() in hid-core

[Benjamin Tissoires <benjamin.tissoires@redhat.com>]

hid_find_max_report() was used both in usbhid and i2c-hid.
Put it in core to avoid code duplication.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
---
 drivers/hid/hid-core.c        | 29 +++++++++++++++++++++++++++++
 drivers/hid/i2c-hid/i2c-hid.c | 15 +++------------
 drivers/hid/usbhid/hid-core.c | 16 ----------------
 include/linux/hid.h           |  2 ++
 4 files changed, 34 insertions(+), 28 deletions(-)

diff --git a/drivers/hid/hid-core.c b/drivers/hid/hid-core.c
index 34c53fc..25d7903 100644
--- a/drivers/hid/hid-core.c
+++ b/drivers/hid/hid-core.c
@@ -1145,6 +1145,35 @@ void hid_output_report(struct hid_report *report, __u8 *data)
 EXPORT_SYMBOL_GPL(hid_output_report);
 
 /*
+ * Return the length (in bytes) of a report
+ */
+int hid_get_report_length(struct hid_report *report)
+{
+	return report->size ? ((report->size - 1) >> 3) + 1 +
+		report->device->report_enum[report->type].numbered : 0;
+}
+EXPORT_SYMBOL_GPL(hid_get_report_length);
+
+/*
+ * Traverse the supplied list of reports and find the longest
+ */
+void hid_find_max_report(struct hid_device *hid, unsigned int type,
+		unsigned int *max)
+{
+	struct hid_report *report;
+	unsigned int size;
+
+	/* We should not rely on wMaxInputLength, as some devices may set it to
+	 * a wrong length. */
+	list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
+		size = hid_get_report_length(report);
+		if (*max < size)
+			*max = size;
+	}
+}
+EXPORT_SYMBOL_GPL(hid_find_max_report);
+
+/*
  * Set a field value. The report this field belongs to has to be
  * created and transferred to the device, to set this value in the
  * device.
diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index 2b1799a..5aa1dc0 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -390,8 +390,7 @@ static irqreturn_t i2c_hid_irq(int irq, void *dev_id)
 
 static int i2c_hid_get_report_length(struct hid_report *report)
 {
-	return ((report->size - 1) >> 3) + 1 +
-		report->device->report_enum[report->type].numbered + 2;
+	return hid_get_report_length(report) + 2;
 }
 
 static void i2c_hid_init_report(struct hid_report *report, u8 *buffer,
@@ -456,16 +455,8 @@ static void i2c_hid_init_reports(struct hid_device *hid)
 static void i2c_hid_find_max_report(struct hid_device *hid, unsigned int type,
 		unsigned int *max)
 {
-	struct hid_report *report;
-	unsigned int size;
-
-	/* We should not rely on wMaxInputLength, as some devices may set it to
-	 * a wrong length. */
-	list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
-		size = i2c_hid_get_report_length(report);
-		if (*max < size)
-			*max = size;
-	}
+	hid_find_max_report(hid, type, max);
+	*max += 2;
 }
 
 static void i2c_hid_free_buffers(struct i2c_hid *ihid)
diff --git a/drivers/hid/usbhid/hid-core.c b/drivers/hid/usbhid/hid-core.c
index effcd3d..5cf7ddb 100644
--- a/drivers/hid/usbhid/hid-core.c
+++ b/drivers/hid/usbhid/hid-core.c
@@ -869,22 +869,6 @@ void usbhid_set_leds(struct hid_device *hid)
 }
 EXPORT_SYMBOL_GPL(usbhid_set_leds);
 
-/*
- * Traverse the supplied list of reports and find the longest
- */
-static void hid_find_max_report(struct hid_device *hid, unsigned int type,
-		unsigned int *max)
-{
-	struct hid_report *report;
-	unsigned int size;
-
-	list_for_each_entry(report, &hid->report_enum[type].report_list, list) {
-		size = ((report->size - 1) >> 3) + 1 + hid->report_enum[type].numbered;
-		if (*max < size)
-			*max = size;
-	}
-}
-
 static int hid_alloc_buffers(struct usb_device *dev, struct hid_device *hid)
 {
 	struct usbhid_device *usbhid = hid->driver_data;
diff --git a/include/linux/hid.h b/include/linux/hid.h
index b7b5ff2..9b6c71c 100644
--- a/include/linux/hid.h
+++ b/include/linux/hid.h
@@ -736,6 +736,8 @@ extern void hidinput_report_event(struct hid_device *hid, struct hid_report *rep
 extern int hidinput_connect(struct hid_device *hid, unsigned int force);
 extern void hidinput_disconnect(struct hid_device *);
 
+int hid_get_report_length(struct hid_report *);
+void hid_find_max_report(struct hid_device *, unsigned int, unsigned int *);
 int hid_set_field(struct hid_field *, unsigned, __s32);
 int hid_input_report(struct hid_device *, int type, u8 *, int, int);
 int hidinput_find_field(struct hid_device *hid, unsigned int type, unsigned int code, struct hid_field **field);
-- 
1.8.1.4