V4L/DVB (6691): pvrusb2: Rework pipeline state control

This is a new implementation for video pipeline control within the
pvrusb2 driver.  Actual start/stop of the pipeline is moved to the
driver's kernel thread.  Pipeline stages are controlled autonomously
based on surrounding pipeline or application control state.  Kernel
thread management is also cleaned up and moved into the internal
control structure of the driver, solving a set up / tear down race
along the way.  Better failure recovery is implemented with this new
control strategy.  Also with this change comes better control of the
cx23416 encoder, building on additional information learned about the
peculiarities of controlling this part (this information was the
original trigger for this rework).  With this change, overall encoder
stability should be considerably improved.  Yes, this is a large
change for this driver, but due to the nature of the feature being
worked on, the changes are fairly pervasive and would be difficult to
break into smaller pieces with any semblence of step-wise stability.

Signed-off-by: Mike Isely <isely@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>

1 files changed, 70 insertions, 65 deletions

diff --git a/drivers/media/video/pvrusb2/pvrusb2-hdw.h b/drivers/media/video/pvrusb2/pvrusb2-hdw.h
index e2f9d5e4cb65..383685f7c81f 100644
--- a/drivers/media/video/pvrusb2/pvrusb2-hdw.h
+++ b/drivers/media/video/pvrusb2/pvrusb2-hdw.h
@@ -44,27 +44,6 @@
 #define PVR2_CVAL_INPUT_COMPOSITE 2
 #define PVR2_CVAL_INPUT_RADIO 3
 
-/* Subsystem definitions - these are various pieces that can be
-   independently stopped / started.  Usually you don't want to mess with
-   this directly (let the driver handle things itself), but it is useful
-   for debugging. */
-#define PVR2_SUBSYS_B_ENC_FIRMWARE        0
-#define PVR2_SUBSYS_B_ENC_CFG             1
-#define PVR2_SUBSYS_B_DIGITIZER_RUN       2
-#define PVR2_SUBSYS_B_USBSTREAM_RUN       3
-#define PVR2_SUBSYS_B_ENC_RUN             4
-
-#define PVR2_SUBSYS_CFG_ALL ( \
-	(1 << PVR2_SUBSYS_B_ENC_FIRMWARE) | \
-	(1 << PVR2_SUBSYS_B_ENC_CFG) )
-#define PVR2_SUBSYS_RUN_ALL ( \
-	(1 << PVR2_SUBSYS_B_DIGITIZER_RUN) | \
-	(1 << PVR2_SUBSYS_B_USBSTREAM_RUN) | \
-	(1 << PVR2_SUBSYS_B_ENC_RUN) )
-#define PVR2_SUBSYS_ALL ( \
-	PVR2_SUBSYS_CFG_ALL | \
-	PVR2_SUBSYS_RUN_ALL )
-
 enum pvr2_config {
 	pvr2_config_empty,    /* No configuration */
 	pvr2_config_mpeg,     /* Encoded / compressed video */
@@ -79,8 +58,41 @@ enum pvr2_v4l_type {
 	pvr2_v4l_type_radio,
 };
 
+/* Major states that we can be in:
+ *
+ *  DEAD - Device is in an unusable state and cannot be recovered.  This
+ *  can happen if we completely lose the ability to communicate with it
+ *  (but it might still on the bus).  In this state there's nothing we can
+ *  do; it must be replugged in order to recover.
+ *
+ *  COLD - Device is in an unusuable state, needs microcontroller firmware.
+ *
+ *  WARM - We can communicate with the device and the proper
+ *  microcontroller firmware is running, but other device initialization is
+ *  still needed (e.g. encoder firmware).
+ *
+ *  ERROR - A problem prevents capture operation (e.g. encoder firmware
+ *  missing).
+ *
+ *  READY - Device is operational, but not streaming.
+ *
+ *  RUN - Device is streaming.
+ *
+ */
+#define PVR2_STATE_NONE 0
+#define PVR2_STATE_DEAD 1
+#define PVR2_STATE_COLD 2
+#define PVR2_STATE_WARM 3
+#define PVR2_STATE_ERROR 4
+#define PVR2_STATE_READY 5
+#define PVR2_STATE_RUN 6
+
+/* Translate configuration enum to a string label */
 const char *pvr2_config_get_name(enum pvr2_config);
 
+/* Translate a master state enum to a string label */
+const char *pvr2_hdw_get_state_name(unsigned int);
+
 struct pvr2_hdw;
 
 /* Create and return a structure for interacting with the underlying
@@ -88,28 +100,13 @@ struct pvr2_hdw;
 struct pvr2_hdw *pvr2_hdw_create(struct usb_interface *intf,
 				 const struct usb_device_id *devid);
 
-/* Poll for background activity (if any) */
-void pvr2_hdw_poll(struct pvr2_hdw *);
-
-/* Trigger a poll to take place later at a convenient time */
-void pvr2_hdw_poll_trigger_unlocked(struct pvr2_hdw *);
-
-/* Register a callback used to trigger a future poll */
-void pvr2_hdw_setup_poll_trigger(struct pvr2_hdw *,
-				 void (*func)(void *),
-				 void *data);
-
 /* Destroy hardware interaction structure */
 void pvr2_hdw_destroy(struct pvr2_hdw *);
 
-/* Set up the structure and attempt to put the device into a usable state.
-   This can be a time-consuming operation, which is why it is not done
-   internally as part of the create() step.  Return value is exactly the
-   same as pvr2_hdw_init_ok(). */
-int pvr2_hdw_setup(struct pvr2_hdw *);
-
-/* Initialization succeeded */
-int pvr2_hdw_init_ok(struct pvr2_hdw *);
+/* Register a function to be called whenever the master state changes. */
+void pvr2_hdw_set_state_callback(struct pvr2_hdw *,
+				 void (*callback_func)(void *),
+				 void *callback_data);
 
 /* Return true if in the ready (normal) state */
 int pvr2_hdw_dev_ok(struct pvr2_hdw *);
@@ -167,6 +164,9 @@ int pvr2_hdw_set_streaming(struct pvr2_hdw *,int);
 /* Find out if streaming is on */
 int pvr2_hdw_get_streaming(struct pvr2_hdw *);
 
+/* Retrieve driver overall state */
+int pvr2_hdw_get_state(struct pvr2_hdw *);
+
 /* Configure the type of stream to generate */
 int pvr2_hdw_set_stream_type(struct pvr2_hdw *, enum pvr2_config);
 
@@ -177,26 +177,6 @@ struct pvr2_stream *pvr2_hdw_get_video_stream(struct pvr2_hdw *);
 int pvr2_hdw_get_stdenum_value(struct pvr2_hdw *hdw,struct v4l2_standard *std,
 			       unsigned int idx);
 
-/* Enable / disable various pieces of hardware.  Items to change are
-   identified by bit positions within msk, and new state for each item is
-   identified by corresponding bit positions within val. */
-void pvr2_hdw_subsys_bit_chg(struct pvr2_hdw *hdw,
-			     unsigned long msk,unsigned long val);
-
-/* Retrieve mask indicating which pieces of hardware are currently enabled
-   / configured. */
-unsigned long pvr2_hdw_subsys_get(struct pvr2_hdw *);
-
-/* Adjust mask of what get shut down when streaming is stopped.  This is a
-   debugging aid. */
-void pvr2_hdw_subsys_stream_bit_chg(struct pvr2_hdw *hdw,
-				    unsigned long msk,unsigned long val);
-
-/* Retrieve mask indicating which pieces of hardware are disabled when
-   streaming is turned off. */
-unsigned long pvr2_hdw_subsys_stream_get(struct pvr2_hdw *);
-
-
 /* Enable / disable retrieval of CPU firmware or prom contents.  This must
    be enabled before pvr2_hdw_cpufw_get() will function.  Note that doing
    this may prevent the device from running (and leaving this mode may
@@ -253,6 +233,9 @@ void pvr2_hdw_cpureset_assert(struct pvr2_hdw *,int);
 /* Execute a USB-commanded device reset */
 void pvr2_hdw_device_reset(struct pvr2_hdw *);
 
+/* Reset worker's error trapping circuit breaker */
+int pvr2_hdw_untrip(struct pvr2_hdw *);
+
 /* Execute hard reset command (after this point it's likely that the
    encoder will have to be reconfigured).  This also clears the "useless"
    state. */
@@ -275,11 +258,21 @@ int pvr2_hdw_gpio_chg_out(struct pvr2_hdw *hdw,u32 msk,u32 val);
 struct pvr2_hdw_debug_info {
 	int big_lock_held;
 	int ctl_lock_held;
-	int flag_ok;
 	int flag_disconnected;
 	int flag_init_ok;
-	int flag_streaming_enabled;
-	unsigned long subsys_flags;
+	int flag_ok;
+	int fw1_state;
+	int flag_decoder_missed;
+	int flag_tripped;
+	int state_encoder_ok;
+	int state_encoder_run;
+	int state_decoder_run;
+	int state_usbstream_run;
+	int state_decoder_quiescent;
+	int state_pipeline_config;
+	int state_pipeline_req;
+	int state_pipeline_pause;
+	int state_pipeline_idle;
 	int cmd_debug_state;
 	int cmd_debug_write_len;
 	int cmd_debug_read_len;
@@ -295,8 +288,20 @@ struct pvr2_hdw_debug_info {
    diagnosing lockups.  Note that this operation is completed without any
    kind of locking and so it is not atomic and may yield inconsistent
    results.  This is *purely* a debugging aid. */
-void pvr2_hdw_get_debug_info(const struct pvr2_hdw *hdw,
-			     struct pvr2_hdw_debug_info *);
+void pvr2_hdw_get_debug_info_unlocked(const struct pvr2_hdw *hdw,
+				      struct pvr2_hdw_debug_info *);
+
+/* Intrusively retrieve internal state info - this is useful for
+   diagnosing overall driver state.  This operation synchronizes against
+   the overall driver mutex - so if there are locking problems this will
+   likely hang!  This is *purely* a debugging aid. */
+void pvr2_hdw_get_debug_info_locked(struct pvr2_hdw *hdw,
+				    struct pvr2_hdw_debug_info *);
+
+/* Report out several lines of text that describes driver internal state.
+   Results are written into the passed-in buffer. */
+unsigned int pvr2_hdw_state_report(struct pvr2_hdw *hdw,
+				   char *buf_ptr,unsigned int buf_size);
 
 /* Cause modules to log their state once */
 void pvr2_hdw_trigger_module_log(struct pvr2_hdw *hdw);