HID: i2c-hid: implement ll_driver transport-layer callbacks

Add output_report and raw_request to i2c-hid.
The current implementation of i2c_hid_output_raw_report decides
by itself if it should use a direct send of the output report
or use the data register (SET_REPORT). Split that by reimplement
the logic in __i2c_hid_output_raw_report() which will be dropped
soon.

Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

1 files changed, 60 insertions, 9 deletions

diff --git a/drivers/hid/i2c-hid/i2c-hid.c b/drivers/hid/i2c-hid/i2c-hid.c
index f4ea7343e823..b48f49d1f0dd 100644
--- a/drivers/hid/i2c-hid/i2c-hid.c
+++ b/drivers/hid/i2c-hid/i2c-hid.c
@@ -256,12 +256,21 @@ static int i2c_hid_get_report(struct i2c_client *client, u8 reportType,
         return 0;
 }
 
-static int i2c_hid_set_report(struct i2c_client *client, u8 reportType,
-                u8 reportID, unsigned char *buf, size_t data_len)
+/**
+ * i2c_hid_set_or_send_report: forward an incoming report to the device
+ * @client: the i2c_client of the device
+ * @reportType: 0x03 for HID_FEATURE_REPORT ; 0x02 for HID_OUTPUT_REPORT
+ * @reportID: the report ID
+ * @buf: the actual data to transfer, without the report ID
+ * @len: size of buf
+ * @use_data: true: use SET_REPORT HID command, false: send plain OUTPUT report
+ */
+static int i2c_hid_set_or_send_report(struct i2c_client *client, u8 reportType,
+                u8 reportID, unsigned char *buf, size_t data_len, bool use_data)
 {
         struct i2c_hid *ihid = i2c_get_clientdata(client);
         u8 *args = ihid->argsbuf;
-        const struct i2c_hid_cmd * hidcmd = &hid_set_report_cmd;
+        const struct i2c_hid_cmd *hidcmd;
         int ret;
         u16 dataRegister = le16_to_cpu(ihid->hdesc.wDataRegister);
         u16 outputRegister = le16_to_cpu(ihid->hdesc.wOutputRegister);
@@ -278,6 +287,9 @@ static int i2c_hid_set_report(struct i2c_client *client, u8 reportType,
 
         i2c_hid_dbg(ihid, "%s\n", __func__);
 
+        if (!use_data && maxOutputLength == 0)
+                return -ENOSYS;
+
         if (reportID >= 0x0F) {
                 args[index++] = reportID;
                 reportID = 0x0F;
@@ -287,9 +299,10 @@ static int i2c_hid_set_report(struct i2c_client *client, u8 reportType,
          * use the data register for feature reports or if the device does not
          * support the output register
          */
-        if (reportType == 0x03 || maxOutputLength == 0) {
+        if (use_data) {
                 args[index++] = dataRegister & 0xFF;
                 args[index++] = dataRegister >> 8;
+                hidcmd = &hid_set_report_cmd;
         } else {
                 args[index++] = outputRegister & 0xFF;
                 args[index++] = outputRegister >> 8;
@@ -550,7 +563,7 @@ static int i2c_hid_get_raw_report(struct hid_device *hid,
 }
 
 static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
-                size_t count, unsigned char report_type)
+                size_t count, unsigned char report_type, bool use_data)
 {
         struct i2c_client *client = hid->driver_data;
         int report_id = buf[0];
@@ -564,9 +577,9 @@ static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
                 count--;
         }
 
-        ret = i2c_hid_set_report(client,
+        ret = i2c_hid_set_or_send_report(client,
                                 report_type == HID_FEATURE_REPORT ? 0x03 : 0x02,
-                                report_id, buf, count);
+                                report_id, buf, count, use_data);
 
         if (report_id && ret >= 0)
                 ret++; /* add report_id to the number of transfered bytes */
@@ -574,6 +587,42 @@ static int i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
         return ret;
 }
 
+static int __i2c_hid_output_raw_report(struct hid_device *hid, __u8 *buf,
+                size_t count, unsigned char report_type)
+{
+        struct i2c_client *client = hid->driver_data;
+        struct i2c_hid *ihid = i2c_get_clientdata(client);
+        bool data = true; /* SET_REPORT */
+
+        if (report_type == HID_OUTPUT_REPORT)
+                data = le16_to_cpu(ihid->hdesc.wMaxOutputLength) == 0;
+
+        return i2c_hid_output_raw_report(hid, buf, count, report_type, data);
+}
+
+static int i2c_hid_output_report(struct hid_device *hid, __u8 *buf,
+                size_t count)
+{
+        return i2c_hid_output_raw_report(hid, buf, count, HID_OUTPUT_REPORT,
+                        false);
+}
+
+static int i2c_hid_raw_request(struct hid_device *hid, unsigned char reportnum,
+                               __u8 *buf, size_t len, unsigned char rtype,
+                               int reqtype)
+{
+        switch (reqtype) {
+        case HID_REQ_GET_REPORT:
+                return i2c_hid_get_raw_report(hid, reportnum, buf, len, rtype);
+        case HID_REQ_SET_REPORT:
+                if (buf[0] != reportnum)
+                        return -EINVAL;
+                return i2c_hid_output_raw_report(hid, buf, len, rtype, true);
+        default:
+                return -EIO;
+        }
+}
+
 static void i2c_hid_request(struct hid_device *hid, struct hid_report *rep,
                 int reqtype)
 {
@@ -597,7 +646,7 @@ static void i2c_hid_request(struct hid_device *hid, struct hid_report *rep,
                 break;
         case HID_REQ_SET_REPORT:
                 hid_output_report(rep, buf);
-                i2c_hid_output_raw_report(hid, buf, len, rep->type);
+                i2c_hid_output_raw_report(hid, buf, len, rep->type, true);
                 break;
         }
 
@@ -761,6 +810,8 @@ static struct hid_ll_driver i2c_hid_ll_driver = {
         .close = i2c_hid_close,
         .power = i2c_hid_power,
         .request = i2c_hid_request,
+        .output_report = i2c_hid_output_report,
+        .raw_request = i2c_hid_raw_request,
 };
 
 static int i2c_hid_init_irq(struct i2c_client *client)
@@ -1005,7 +1056,7 @@ static int i2c_hid_probe(struct i2c_client *client,
 
         hid->driver_data = client;
         hid->ll_driver = &i2c_hid_ll_driver;
-        hid->hid_output_raw_report = i2c_hid_output_raw_report;
+        hid->hid_output_raw_report = __i2c_hid_output_raw_report;
         hid->dev.parent = &client->dev;
         ACPI_COMPANION_SET(&hid->dev, ACPI_COMPANION(&client->dev));
         hid->bus = BUS_I2C;