V4L/DVB (13139): gspca_mr97310a: Improve VGA sensor type detection

Improve (and also simplify :) gspca_mr97310a: VGA sensor type detection.
As it was still failing on some machines (not with some cams, but on
some machines interesting enough).

Signed-off-by: Theodore Kilgore <kilgota@banach.math.auburn.edu>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

1 files changed, 34 insertions, 55 deletions

diff --git a/drivers/media/video/gspca/mr97310a.c b/drivers/media/video/gspca/mr97310a.c
index f4c83b367900..abc56e37efcb 100644
--- a/drivers/media/video/gspca/mr97310a.c
+++ b/drivers/media/video/gspca/mr97310a.c
@@ -431,12 +431,13 @@ static int sd_config(struct gspca_dev *gspca_dev,
         if (err_code < 0)
                 return err_code;
 
+        err_code = stream_start(gspca_dev);
+        if (err_code < 0)
+                return err_code;
+
         if (id->idProduct == 0x010e) {
                 sd->cam_type = CAM_TYPE_CIF;
                 cam->nmodes--;
-                err_code = stream_start(gspca_dev);
-                if (err_code < 0)
-                        return err_code;
                 err_code = cam_get_response16(gspca_dev, 0x06, 1);
                 if (err_code < 0)
                         return err_code;
@@ -476,74 +477,52 @@ static int sd_config(struct gspca_dev *gspca_dev,
         } else {
                 sd->cam_type = CAM_TYPE_VGA;
 
-                /*
-                 * VGA cams also have two different sensor types. Detection
-                 * requires a two-step process.
-                 *
-                 * Here is a report on the result of the first test for the
-                 * known MR97310a VGA cameras. If you have another to report,
-                 * please do.
-                 *
-                 * Name         byte just read                  sd->sensor_type
-                 *                              sd->do_lcd_stop
-                 * Aiptek Pencam VGA+   0x31            0       1
-                 * ION digital          0x31            0       1
-                 * Sakar Digital 77379  0x31            0       1
-                 * Argus DC-1620        0x30            1       0
-                 * Argus QuickClix      0x30            1       1 (see note)
-                 * Note that this test fails to distinguish sd->sensor_type
-                 * for the two cameras which have reported 0x30.
-                 * Another test will be run on them.
-                 * But the sd->do_lcd_stop setting is needed, too.
-                 */
-
-                err_code = cam_get_response16(gspca_dev, 0x20, 1);
-                if (err_code < 0)
-                        return err_code;
-                sd->sensor_type = gspca_dev->usb_buf[0] & 1;
-                sd->do_lcd_stop = (~gspca_dev->usb_buf[0]) & 1;
-                err_code = stream_start(gspca_dev);
+                err_code = cam_get_response16(gspca_dev, 0x07, 1);
                 if (err_code < 0)
                         return err_code;
 
                 /*
-                 * A second test can now resolve any remaining ambiguity in the
-                 * identification of the camera's sensor type. Specifically,
-                 * it now gives the correct sensor_type for the Argus DC-1620
-                 * and the Argus QuickClix.
-                 *
-                 * This second test is only run if needed,
-                 * but additional results from testing some other cameras
-                 * are recorded here, too:
+                 * Here is a table of the responses to the previous command
+                 * from the known MR97310A VGA cameras.
                  *
                  * Name                 gspca_dev->usb_buf[]    sd->sensor_type
+                 *                              sd->do_lcd_stop
+                 * Aiptek Pencam VGA+   0300            0               1
+                 * ION digital          0350            0               1
+                 * Argus DC-1620        0450            1               0
+                 * Argus QuickClix      0420            1               1
                  *
-                 * Aiptek Pencam VGA+   0300    (test not needed)       1
-                 * ION digital          0350    (test not needed)       1
-                 * Argus DC-1620        0450    (remains as type 0)     0
-                 * Argus QuickClix      0420    (corrected to type 1)   1
+                 * Based upon these results, we assume default settings
+                 * and then correct as necessary, as follows.
                  *
-                 * This test even seems able to distinguish one VGA cam from
-                 * another which may be useful. However, the CIF type 1 cameras
-                 * do not like it.
                  */
 
-                if (!sd->sensor_type) {
-                        err_code = cam_get_response16(gspca_dev, 0x07, 1);
-                        if (err_code < 0)
-                                return err_code;
-
+                sd->sensor_type = 1;
+                sd->do_lcd_stop = 0;
+                if ((gspca_dev->usb_buf[0] != 0x03) &&
+                                        (gspca_dev->usb_buf[0] != 0x04)) {
+                        PDEBUG(D_ERR, "Unknown VGA Sensor id Byte 0: %02x",
+                                        gspca_dev->usb_buf[1]);
+                        PDEBUG(D_ERR, "Defaults assumed, may not work");
+                        PDEBUG(D_ERR, "Please report this");
+                }
+                if (gspca_dev->usb_buf[0] == 0x04) {
+                        sd->do_lcd_stop = 1;
                         switch (gspca_dev->usb_buf[1]) {
                         case 0x50:
+                                sd->sensor_type = 0;
+                                PDEBUG(D_PROBE, "sensor_type corrected to 0");
                                 break;
                         case 0x20:
-                                sd->sensor_type = 1;
-                                PDEBUG(D_PROBE, "sensor_type corrected to 1");
+                                /* Nothing to do here. */
                                 break;
                         default:
-                                PDEBUG(D_ERR, "Unknown VGA Sensor id : %02x",
-                                       gspca_dev->usb_buf[1]);
-                                return -ENODEV;
+                                PDEBUG(D_ERR,
+                                        "Unknown VGA Sensor id Byte 1: %02x",
+                                        gspca_dev->usb_buf[1]);
+                                PDEBUG(D_ERR,
+                                        "Defaults assumed, may not work");
+                                PDEBUG(D_ERR, "Please report this");
                         }
                 }
                 PDEBUG(D_PROBE, "MR97310A VGA camera detected, sensor: %d",