From c0675d0b2a15d6df9ff2e517c7e3b83043f470cf Mon Sep 17 00:00:00 2001 From: Matthias Schwarzott Date: Sun, 5 Nov 2017 09:25:07 -0500 Subject: [PATCH] media: si2165: add DVBv5 C/N statistics for DVB-C Add C/N statistics in dB to read_status (DVBv5). Signed-off-by: Matthias Schwarzott Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb-frontends/si2165.c | 43 +++++++++++++++++++++++++++++-- drivers/media/dvb-frontends/si2165_priv.h | 1 + 2 files changed, 42 insertions(+), 2 deletions(-) diff --git a/drivers/media/dvb-frontends/si2165.c b/drivers/media/dvb-frontends/si2165.c index 30ceba6..777b7d0 100644 --- a/drivers/media/dvb-frontends/si2165.c +++ b/drivers/media/dvb-frontends/si2165.c @@ -116,6 +116,17 @@ static int si2165_readreg16(struct si2165_state *state, return ret; } +static int si2165_readreg24(struct si2165_state *state, + const u16 reg, u32 *val) +{ + u8 buf[3]; + + int ret = si2165_read(state, reg, buf, 3); + *val = buf[0] | buf[1] << 8 | buf[2] << 16; + dev_dbg(&state->client->dev, "reg read: R(0x%04x)=0x%06x\n", reg, *val); + return ret; +} + static int si2165_writereg8(struct si2165_state *state, const u16 reg, u8 val) { return regmap_write(state->regmap, reg, val); @@ -518,6 +529,7 @@ static int si2165_init(struct dvb_frontend *fe) { int ret = 0; struct si2165_state *state = fe->demodulator_priv; + struct dtv_frontend_properties *c = &fe->dtv_property_cache; u8 val; u8 patch_version = 0x00; @@ -627,6 +639,10 @@ static int si2165_init(struct dvb_frontend *fe) if (ret < 0) return ret; + c = &state->fe.dtv_property_cache; + c->cnr.len = 1; + c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE; + return 0; error: return ret; @@ -652,9 +668,10 @@ static int si2165_read_status(struct dvb_frontend *fe, enum fe_status *status) { int ret; u8 u8tmp; + u32 u32tmp; struct si2165_state *state = fe->demodulator_priv; - struct dtv_frontend_properties *p = &fe->dtv_property_cache; - u32 delsys = p->delivery_system; + struct dtv_frontend_properties *c = &fe->dtv_property_cache; + u32 delsys = c->delivery_system; *status = 0; @@ -699,6 +716,28 @@ static int si2165_read_status(struct dvb_frontend *fe, enum fe_status *status) *status |= FE_HAS_LOCK; } + /* CNR */ + if (delsys == SYS_DVBC_ANNEX_A && *status & FE_HAS_VITERBI) { + ret = si2165_readreg24(state, REG_C_N, &u32tmp); + if (ret < 0) + return ret; + /* + * svalue = + * 1000 * c_n/dB = + * 1000 * 10 * log10(2^24 / regval) = + * 1000 * 10 * (log10(2^24) - log10(regval)) = + * 1000 * 10 * (intlog10(2^24) - intlog10(regval)) / 2^24 + * + * intlog10(x) = log10(x) * 2^24 + * intlog10(2^24) = log10(2^24) * 2^24 = 121210686 + */ + u32tmp = (1000 * 10 * (121210686 - (u64)intlog10(u32tmp))) + >> 24; + c->cnr.stat[0].scale = FE_SCALE_DECIBEL; + c->cnr.stat[0].svalue = u32tmp; + } else + c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE; + return 0; } diff --git a/drivers/media/dvb-frontends/si2165_priv.h b/drivers/media/dvb-frontends/si2165_priv.h index 47f18ff..9d79e86 100644 --- a/drivers/media/dvb-frontends/si2165_priv.h +++ b/drivers/media/dvb-frontends/si2165_priv.h @@ -74,6 +74,7 @@ struct si2165_config { #define REG_KP_LOCK 0x023a #define REG_UNKNOWN_24C 0x024c #define REG_CENTRAL_TAP 0x0261 +#define REG_C_N 0x026c #define REG_EQ_AUTO_CONTROL 0x0278 #define REG_UNKNOWN_27C 0x027c #define REG_START_SYNCHRO 0x02e0 -- 2.7.4