From cf5b0cc26c7aff4bb8cbf0f5f411ce2249acc7e2 Mon Sep 17 00:00:00 2001 From: Malcolm Priestley Date: Tue, 24 Dec 2013 13:17:12 -0300 Subject: m88rs2000: add m88rs2000_set_carrieroffset commit 06af15d1b6f45c60358feab88004472e5428f01c upstream. Set the carrier offset correctly using the default mclk values. Add function m88rs2000_get_mclk to calculate the mclk value against crystal frequency which will later be used for other functions. Add function m88rs2000_set_carrieroffset to calculate and set the offset value. variable offset becomes a signed value. Register 0x86 is set the appropriate value according to remainder value of frequency % 192857 calculation as shown. Signed-off-by: Malcolm Priestley Signed-off-by: Mauro Carvalho Chehab Signed-off-by: Greg Kroah-Hartman --- drivers/media/dvb-frontends/m88rs2000.c | 77 ++++++++++++++++++++++++--------- drivers/media/dvb-frontends/m88rs2000.h | 2 + 2 files changed, 59 insertions(+), 20 deletions(-) (limited to 'drivers') diff --git a/drivers/media/dvb-frontends/m88rs2000.c b/drivers/media/dvb-frontends/m88rs2000.c index 4da5272075c..8091653e886 100644 --- a/drivers/media/dvb-frontends/m88rs2000.c +++ b/drivers/media/dvb-frontends/m88rs2000.c @@ -110,6 +110,52 @@ static u8 m88rs2000_readreg(struct m88rs2000_state *state, u8 reg) return b1[0]; } +static u32 m88rs2000_get_mclk(struct dvb_frontend *fe) +{ + struct m88rs2000_state *state = fe->demodulator_priv; + u32 mclk; + u8 reg; + /* Must not be 0x00 or 0xff */ + reg = m88rs2000_readreg(state, 0x86); + if (!reg || reg == 0xff) + return 0; + + reg /= 2; + reg += 1; + + mclk = (u32)(reg * RS2000_FE_CRYSTAL_KHZ + 28 / 2) / 28; + + return mclk; +} + +static int m88rs2000_set_carrieroffset(struct dvb_frontend *fe, s16 offset) +{ + struct m88rs2000_state *state = fe->demodulator_priv; + u32 mclk; + s32 tmp; + u8 reg; + int ret; + + mclk = m88rs2000_get_mclk(fe); + if (!mclk) + return -EINVAL; + + tmp = (offset * 4096 + (s32)mclk / 2) / (s32)mclk; + if (tmp < 0) + tmp += 4096; + + /* Carrier Offset */ + ret = m88rs2000_writereg(state, 0x9c, (u8)(tmp >> 4)); + + reg = m88rs2000_readreg(state, 0x9d); + reg &= 0xf; + reg |= (u8)(tmp & 0xf) << 4; + + ret |= m88rs2000_writereg(state, 0x9d, reg); + + return ret; +} + static int m88rs2000_set_symbolrate(struct dvb_frontend *fe, u32 srate) { struct m88rs2000_state *state = fe->demodulator_priv; @@ -540,9 +586,8 @@ static int m88rs2000_set_frontend(struct dvb_frontend *fe) struct dtv_frontend_properties *c = &fe->dtv_property_cache; fe_status_t status; int i, ret = 0; - s32 tmp; u32 tuner_freq; - u16 offset = 0; + s16 offset = 0; u8 reg; state->no_lock_count = 0; @@ -567,26 +612,18 @@ static int m88rs2000_set_frontend(struct dvb_frontend *fe) if (ret < 0) return -ENODEV; - offset = tuner_freq - c->frequency; + offset = (s16)((s32)tuner_freq - c->frequency); - /* calculate offset assuming 96000kHz*/ - tmp = offset; - tmp *= 65536; - - tmp = (2 * tmp + 96000) / (2 * 96000); - if (tmp < 0) - tmp += 65536; - - offset = tmp & 0xffff; - - ret = m88rs2000_writereg(state, 0x9a, 0x30); - /* Unknown usually 0xc6 sometimes 0xc1 */ - reg = m88rs2000_readreg(state, 0x86); - ret |= m88rs2000_writereg(state, 0x86, reg); - /* Offset lower nibble always 0 */ - ret |= m88rs2000_writereg(state, 0x9c, (offset >> 8)); - ret |= m88rs2000_writereg(state, 0x9d, offset & 0xf0); + /* default mclk value 96.4285 * 2 * 1000 = 192857 */ + if (((c->frequency % 192857) >= (192857 - 3000)) || + (c->frequency % 192857) <= 3000) + ret = m88rs2000_writereg(state, 0x86, 0xc2); + else + ret = m88rs2000_writereg(state, 0x86, 0xc6); + ret |= m88rs2000_set_carrieroffset(fe, offset); + if (ret < 0) + return -ENODEV; /* Reset Demod */ ret = m88rs2000_tab_set(state, fe_reset); diff --git a/drivers/media/dvb-frontends/m88rs2000.h b/drivers/media/dvb-frontends/m88rs2000.h index 14ce31e76ae..0a50ea90736 100644 --- a/drivers/media/dvb-frontends/m88rs2000.h +++ b/drivers/media/dvb-frontends/m88rs2000.h @@ -53,6 +53,8 @@ static inline struct dvb_frontend *m88rs2000_attach( } #endif /* CONFIG_DVB_M88RS2000 */ +#define RS2000_FE_CRYSTAL_KHZ 27000 + enum { DEMOD_WRITE = 0x1, WRITE_DELAY = 0x10, -- cgit v1.2.3