V4L/DVB (12825): tm6000: I2C reading operations is not reliable on tm6000

tm6000 sometimes can't read from i2c, but this is currently required for
tuner-xc2028 to work.

This patch adds an option to tuner-xc2028 to not rely on i2c reading.

Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

3 files changed, 10 insertions, 2 deletions

diff --git a/drivers/media/common/tuners/tuner-xc2028.c b/drivers/media/common/tuners/tuner-xc2028.c
index 8d2907f38a94..53f0fbb33cc6 100644
--- a/drivers/media/common/tuners/tuner-xc2028.c
+++ b/drivers/media/common/tuners/tuner-xc2028.c
@@ -813,8 +813,14 @@ check_device:
 
         /* Check firmware version against what we downloaded. */
         if (priv->firm_version != ((version & 0xf0) << 4 | (version & 0x0f))) {
-                tuner_err("Incorrect readback of firmware version.\n");
-                goto fail;
+                if (!priv->ctrl.read_not_reliable) {
+                        tuner_err("Incorrect readback of firmware version.\n");
+                        goto fail;
+                } else {
+                        tuner_err("Returned an incorrect version. However, "
+                                  "read is not reliable enough. Ignoring it.\n");
+                        hwmodel = 3028;
+                }
         }
 
         /* Check that the tuner hardware model remains consistent over time. */
diff --git a/drivers/media/common/tuners/tuner-xc2028.h b/drivers/media/common/tuners/tuner-xc2028.h
index e116071810e0..9778c96a5006 100644
--- a/drivers/media/common/tuners/tuner-xc2028.h
+++ b/drivers/media/common/tuners/tuner-xc2028.h
@@ -40,6 +40,7 @@ struct xc2028_ctrl {
         unsigned int            vhfbw7:1;
         unsigned int            uhfbw8:1;
         unsigned int            disable_power_mgmt:1;
+        unsigned int            read_not_reliable:1;
         unsigned int            demod;
         enum firmware_type      type:2;
 };
diff --git a/drivers/staging/tm6000/tm6000-cards.c b/drivers/staging/tm6000/tm6000-cards.c
index c0bb3ec35480..23f9672d6937 100644
--- a/drivers/staging/tm6000/tm6000-cards.c
+++ b/drivers/staging/tm6000/tm6000-cards.c
@@ -189,6 +189,7 @@ static void tm6000_config_tuner (struct tm6000_core *dev)
                         ctl.fname = "tm6000-xc3028.fw";
 
                 ctl.mts   = 1;
+                ctl.read_not_reliable = 1;
 
                 xc2028_cfg.tuner = TUNER_XC2028;
                 xc2028_cfg.priv  = &ctl;