[media] dvb: Add DVBv5 statistics properties

The DVBv3 statistics parameters are limited on several ways:
        - It doesn't provide any way to indicate the used measure,
	  so userspace need to guess how to calculate/use it;
        - Only a limited set of stats are supported;
        - Can't be called in a way to require them to be filled
          all at once (atomic reads from the hardware), with may
          cause troubles on interpreting them on userspace;
        - On some OFDM delivery systems, the carriers can be
          independently modulated, having different properties.
          Currently, there's no way to report per-layer stats.
To address the above issues, adding a new DVBv5-based stats API.
While here, correct inner code nomenclature on a few places.

Reviewed-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>

2 files changed, 79 insertions, 2 deletions

diff --git a/include/uapi/linux/dvb/frontend.h b/include/uapi/linux/dvb/frontend.h
index c12d452cb40d..c56d77c496a5 100644
--- a/include/uapi/linux/dvb/frontend.h
+++ b/include/uapi/linux/dvb/frontend.h
@@ -365,7 +365,17 @@ struct dvb_frontend_event {
 #define DTV_INTERLEAVING                        60
 #define DTV_LNA                                 61
 
-#define DTV_MAX_COMMAND                         DTV_LNA
+/* Quality parameters */
+#define DTV_STAT_SIGNAL_STRENGTH        62
+#define DTV_STAT_CNR                    63
+#define DTV_STAT_PRE_ERROR_BIT_COUNT    64
+#define DTV_STAT_PRE_TOTAL_BIT_COUNT    65
+#define DTV_STAT_POST_ERROR_BIT_COUNT   66
+#define DTV_STAT_POST_TOTAL_BIT_COUNT   67
+#define DTV_STAT_ERROR_BLOCK_COUNT      68
+#define DTV_STAT_TOTAL_BLOCK_COUNT      69
+
+#define DTV_MAX_COMMAND         DTV_STAT_TOTAL_BLOCK_COUNT
 
 typedef enum fe_pilot {
         PILOT_ON,
@@ -452,11 +462,78 @@ struct dtv_cmds_h {
         __u32   reserved:30;    /* Align */
 };
 
+/**
+ * Scale types for the quality parameters.
+ * @FE_SCALE_NOT_AVAILABLE: That QoS measure is not available. That
+ *                          could indicate a temporary or a permanent
+ *                          condition.
+ * @FE_SCALE_DECIBEL: The scale is measured in 0.0001 dB steps, typically
+ *                used on signal measures.
+ * @FE_SCALE_RELATIVE: The scale is a relative percentual measure,
+ *                      ranging from 0 (0%) to 0xffff (100%).
+ * @FE_SCALE_COUNTER: The scale counts the occurrence of an event, like
+ *                      bit error, block error, lapsed time.
+ */
+enum fecap_scale_params {
+        FE_SCALE_NOT_AVAILABLE = 0,
+        FE_SCALE_DECIBEL,
+        FE_SCALE_RELATIVE,
+        FE_SCALE_COUNTER
+};
+
+/**
+ * struct dtv_stats - Used for reading a DTV status property
+ *
+ * @value:      value of the measure. Should range from 0 to 0xffff;
+ * @scale:      Filled with enum fecap_scale_params - the scale
+ *              in usage for that parameter
+ *
+ * For most delivery systems, this will return a single value for each
+ * parameter.
+ * It should be noticed, however, that new OFDM delivery systems like
+ * ISDB can use different modulation types for each group of carriers.
+ * On such standards, up to 8 groups of statistics can be provided, one
+ * for each carrier group (called "layer" on ISDB).
+ * In order to be consistent with other delivery systems, the first
+ * value refers to the entire set of carriers ("global").
+ * dtv_status:scale should use the value FE_SCALE_NOT_AVAILABLE when
+ * the value for the entire group of carriers or from one specific layer
+ * is not provided by the hardware.
+ * st.len should be filled with the latest filled status + 1.
+ *
+ * In other words, for ISDB, those values should be filled like:
+ *      u.st.stat.svalue[0] = global statistics;
+ *      u.st.stat.scale[0] = FE_SCALE_DECIBELS;
+ *      u.st.stat.value[1] = layer A statistics;
+ *      u.st.stat.scale[1] = FE_SCALE_NOT_AVAILABLE (if not available);
+ *      u.st.stat.svalue[2] = layer B statistics;
+ *      u.st.stat.scale[2] = FE_SCALE_DECIBELS;
+ *      u.st.stat.svalue[3] = layer C statistics;
+ *      u.st.stat.scale[3] = FE_SCALE_DECIBELS;
+ *      u.st.len = 4;
+ */
+struct dtv_stats {
+        __u8 scale;     /* enum fecap_scale_params type */
+        union {
+                __u64 uvalue;   /* for counters and relative scales */
+                __s64 svalue;   /* for 0.0001 dB measures */
+        };
+} __attribute__ ((packed));
+
+
+#define MAX_DTV_STATS   4
+
+struct dtv_fe_stats {
+        __u8 len;
+        struct dtv_stats stat[MAX_DTV_STATS];
+} __attribute__ ((packed));
+
 struct dtv_property {
         __u32 cmd;
         __u32 reserved[3];
         union {
                 __u32 data;
+                struct dtv_fe_stats st;
                 struct {
                         __u8 data[32];
                         __u32 len;
diff --git a/include/uapi/linux/dvb/version.h b/include/uapi/linux/dvb/version.h
index 827cce7e33e3..e53e2ad4444f 100644
--- a/include/uapi/linux/dvb/version.h
+++ b/include/uapi/linux/dvb/version.h
@@ -24,6 +24,6 @@
 #define _DVBVERSION_H_
 
 #define DVB_API_VERSION 5
-#define DVB_API_VERSION_MINOR 9
+#define DVB_API_VERSION_MINOR 10
 
 #endif /*_DVBVERSION_H_*/