From 37c52abd565aa8d10ffd7f31a37792425d1564df Mon Sep 17 00:00:00 2001 From: Mauro Carvalho Chehab Date: Sat, 17 Dec 2011 20:36:59 -0300 Subject: [PATCH] [media] tda10023: Don't use a magic numbers for QAM modulation Convert the existing data struct to use the QAM modulation macros, instead of assuming that they're numbered from 0 to 5. Signed-off-by: Mauro Carvalho Chehab --- drivers/media/dvb/frontends/tda10023.c | 66 +++++++++++++++++--------- 1 file changed, 43 insertions(+), 23 deletions(-) diff --git a/drivers/media/dvb/frontends/tda10023.c b/drivers/media/dvb/frontends/tda10023.c index a3c34eecdee9..e6c321e799d7 100644 --- a/drivers/media/dvb/frontends/tda10023.c +++ b/drivers/media/dvb/frontends/tda10023.c @@ -298,25 +298,43 @@ static int tda10023_init (struct dvb_frontend *fe) return 0; } +struct qam_params { + u8 qam, lockthr, mseth, aref, agcrefnyq, eragnyq_thd; +}; + static int tda10023_set_parameters (struct dvb_frontend *fe, struct dvb_frontend_parameters *p) { struct tda10023_state* state = fe->demodulator_priv; - - static int qamvals[6][6] = { - // QAM LOCKTHR MSETH AREF AGCREFNYQ ERAGCNYQ_THD - { (5<<2), 0x78, 0x8c, 0x96, 0x78, 0x4c }, // 4 QAM - { (0<<2), 0x87, 0xa2, 0x91, 0x8c, 0x57 }, // 16 QAM - { (1<<2), 0x64, 0x74, 0x96, 0x8c, 0x57 }, // 32 QAM - { (2<<2), 0x46, 0x43, 0x6a, 0x6a, 0x44 }, // 64 QAM - { (3<<2), 0x36, 0x34, 0x7e, 0x78, 0x4c }, // 128 QAM - { (4<<2), 0x26, 0x23, 0x6c, 0x5c, 0x3c }, // 256 QAM + static const struct qam_params qam_params[] = { + /* Modulation QAM LOCKTHR MSETH AREF AGCREFNYQ ERAGCNYQ_THD */ + [QPSK] = { (5<<2), 0x78, 0x8c, 0x96, 0x78, 0x4c }, + [QAM_16] = { (0<<2), 0x87, 0xa2, 0x91, 0x8c, 0x57 }, + [QAM_32] = { (1<<2), 0x64, 0x74, 0x96, 0x8c, 0x57 }, + [QAM_64] = { (2<<2), 0x46, 0x43, 0x6a, 0x6a, 0x44 }, + [QAM_128] = { (3<<2), 0x36, 0x34, 0x7e, 0x78, 0x4c }, + [QAM_256] = { (4<<2), 0x26, 0x23, 0x6c, 0x5c, 0x3c }, }; - - int qam = p->u.qam.modulation; - - if (qam < 0 || qam > 5) + unsigned qam = p->u.qam.modulation; + + /* + * gcc optimizes the code bellow the same way as it would code: + * "if (qam > 5) return -EINVAL;" + * Yet, the code is clearer, as it shows what QAM standards are + * supported by the driver, and avoids the usage of magic numbers on + * it. + */ + switch (qam) { + case QPSK: + case QAM_16: + case QAM_32: + case QAM_64: + case QAM_128: + case QAM_256: + break; + default: return -EINVAL; + } if (fe->ops.tuner_ops.set_params) { fe->ops.tuner_ops.set_params(fe, p); @@ -324,16 +342,18 @@ static int tda10023_set_parameters (struct dvb_frontend *fe, } tda10023_set_symbolrate (state, p->u.qam.symbol_rate); - tda10023_writereg (state, 0x05, qamvals[qam][1]); - tda10023_writereg (state, 0x08, qamvals[qam][2]); - tda10023_writereg (state, 0x09, qamvals[qam][3]); - tda10023_writereg (state, 0xb4, qamvals[qam][4]); - tda10023_writereg (state, 0xb6, qamvals[qam][5]); - -// tda10023_writereg (state, 0x04, (p->inversion?0x12:0x32)); -// tda10023_writebit (state, 0x04, 0x60, (p->inversion?0:0x20)); - tda10023_writebit (state, 0x04, 0x40, 0x40); - tda10023_setup_reg0 (state, qamvals[qam][0]); + tda10023_writereg(state, 0x05, qam_params[qam].lockthr); + tda10023_writereg(state, 0x08, qam_params[qam].mseth); + tda10023_writereg(state, 0x09, qam_params[qam].aref); + tda10023_writereg(state, 0xb4, qam_params[qam].agcrefnyq); + tda10023_writereg(state, 0xb6, qam_params[qam].eragnyq_thd); + +#if 0 + tda10023_writereg(state, 0x04, (p->inversion ? 0x12 : 0x32)); + tda10023_writebit(state, 0x04, 0x60, (p->inversion ? 0 : 0x20)); +#endif + tda10023_writebit(state, 0x04, 0x40, 0x40); + tda10023_setup_reg0(state, qam_params[qam].qam); return 0; } -- 2.20.1