The DVBv3 quality parameters are limited on several ways: - Doesn't provide any way to indicate the used measure; - Userspace need to guess how to calculate the measure; - Only a limited set of stats are supported; - Doesn't provide QoS measure for the OFDM TPS/TMCC carriers, used to detect the network parameters for DVB-T/ISDB-T; - 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; This RFC adds the header definitions meant to solve that issues. After discussed, I'll write a patch for the DocBook and add support for it on some demods. Support for dvbv5-zap and dvbv5-scan tools will also have support for those features. Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> --- include/uapi/linux/dvb/frontend.h | 78 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 77 insertions(+), 1 deletion(-) v3: just a rebase of: http://patchwork.linuxtv.org/patch/9578/ diff --git a/include/uapi/linux/dvb/frontend.h b/include/uapi/linux/dvb/frontend.h index c12d452..a998b9a 100644 --- a/include/uapi/linux/dvb/frontend.h +++ b/include/uapi/linux/dvb/frontend.h @@ -365,7 +365,21 @@ struct dvb_frontend_event { #define DTV_INTERLEAVING 60 #define DTV_LNA 61 -#define DTV_MAX_COMMAND DTV_LNA +/* Quality parameters */ +#define DTV_ENUM_QUALITY 45 /* Enumerates supported QoS parameters */ +#define DTV_QUALITY_SNR 46 +#define DTV_QUALITY_CNR 47 +#define DTV_QUALITY_EsNo 48 +#define DTV_QUALITY_EbNo 49 +#define DTV_QUALITY_RELATIVE 50 +#define DTV_ERROR_BER 51 +#define DTV_ERROR_PER 52 +#define DTV_ERROR_PARAMS 53 /* Error count at TMCC or TPS carrier */ +#define DTV_FE_STRENGTH 54 +#define DTV_FE_SIGNAL 55 +#define DTV_FE_UNC 56 + +#define DTV_MAX_COMMAND DTV_FE_UNC typedef enum fe_pilot { PILOT_ON, @@ -452,12 +466,74 @@ struct dtv_cmds_h { __u32 reserved:30; /* Align */ }; +/** + * Scale types for the quality parameters. + * @FE_SCALE_DECIBEL: The scale is measured in dB, typically + * used on signal measures. + * @FE_SCALE_LINEAR: The scale is linear. + * typically used on error QoS parameters. + * @FE_SCALE_RELATIVE: The scale is relative. + */ +enum fecap_scale_params { + FE_SCALE_DECIBEL, + FE_SCALE_LINEAR, + FE_SCALE_RELATIVE +}; + +/** + * struct dtv_status - 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 + * @min: minimum value. Not used if the scale is relative. + * For non-relative measures, define the measure + * associated with dtv_status.value == 0. + * @max: maximum value. Not used if the scale is relative. + * For non-relative measures, define the measure + * associated with dtv_status.value == 0xffff. + * + * At userspace, min/max values should be used to calculate the + * absolute value of that measure, if fecap_scale_params is not + * FE_SCALE_RELATIVE, using the following formula: + * measure = min + (value * (max - min) / 0xffff) + * + * For error count measures, typically, min = 0, and max = 0xffff, + * and the measure represent the number of errors detected. + * + * Up to 4 status groups can be provided. This is for the + * OFDM standards where the carriers can be grouped into + * independent layers, each with its own modulation. When + * such layers are used (for example, on ISDB-T), the status + * should be filled with: + * stat.status[0] = global statistics; + * stat.status[1] = layer A statistics; + * stat.status[2] = layer B statistics; + * stat.status[3] = layer C statistics. + * and stat.len should be filled with the latest filled status + 1. + * If the frontend doesn't provide a global statistics, + * stat.has_global should be 0. + * Delivery systems that don't use it, should just set stat.len and + * stat.has_global with 1, and fill just stat.status[0]. + */ +struct dtv_status { + __u16 value; + __u16 scale; + __s16 min; + __s16 max; +} __attribute__ ((packed)); + struct dtv_property { __u32 cmd; __u32 reserved[3]; union { __u32 data; struct { + __u8 len; + __u8 has_global; + struct dtv_status status[4]; + } stat; + struct { __u8 data[32]; __u32 len; __u32 reserved1[3]; -- 1.7.11.7 -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
