Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel os linux

[media] af9033: estimate cnr from formula

Use formulas for cnr estimates and get rid of old lut-based estimate.

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

authored by

Antti Palosaari and committed by
Mauro Carvalho Chehab
239dd616 a71e479c

+42 -123
+41 -27
drivers/media/dvb-frontends/af9033.c
··· 622 622 struct af9033_dev *dev = fe->demodulator_priv; 623 623 struct i2c_client *client = dev->client; 624 624 struct dtv_frontend_properties *c = &fe->dtv_property_cache; 625 - int ret, i, tmp = 0; 625 + int ret, tmp = 0; 626 626 u8 buf[7]; 627 - unsigned int utmp; 627 + unsigned int utmp, utmp1; 628 628 629 629 dev_dbg(&client->dev, "\n"); 630 630 ··· 686 686 687 687 /* CNR */ 688 688 if (dev->fe_status & FE_HAS_VITERBI) { 689 - u32 snr_val, snr_lut_size; 690 - const struct val_snr *snr_lut = NULL; 691 - 692 689 /* Read raw SNR value */ 693 690 ret = regmap_bulk_read(dev->regmap, 0x80002c, buf, 3); 694 691 if (ret) 695 692 goto err; 696 693 697 - snr_val = (buf[2] << 16) | (buf[1] << 8) | (buf[0] << 0); 694 + utmp1 = buf[2] << 16 | buf[1] << 8 | buf[0] << 0; 698 695 699 696 /* Read superframe number */ 700 697 ret = regmap_read(dev->regmap, 0x80f78b, &utmp); ··· 699 702 goto err; 700 703 701 704 if (utmp) 702 - snr_val /= utmp; 705 + utmp1 /= utmp; 703 706 704 707 /* Read current transmission mode */ 705 708 ret = regmap_read(dev->regmap, 0x80f900, &utmp); ··· 708 711 709 712 switch ((utmp >> 0) & 3) { 710 713 case 0: 711 - snr_val *= 4; 714 + /* 2k */ 715 + utmp1 *= 4; 712 716 break; 713 717 case 1: 714 - snr_val *= 1; 718 + /* 8k */ 719 + utmp1 *= 1; 715 720 break; 716 721 case 2: 717 - snr_val *= 2; 722 + /* 4k */ 723 + utmp1 *= 2; 718 724 break; 719 725 default: 720 - snr_val *= 0; 726 + utmp1 *= 0; 721 727 break; 722 728 } 723 729 ··· 731 731 732 732 switch ((utmp >> 0) & 3) { 733 733 case 0: 734 - snr_lut_size = ARRAY_SIZE(qpsk_snr_lut); 735 - snr_lut = qpsk_snr_lut; 734 + /* 735 + * QPSK 736 + * CNR[dB] 13 * -log10((1690000 - value) / value) + 2.6 737 + * value [653799, 1689999], 2.6 / 13 = 3355443 738 + */ 739 + utmp1 = clamp(utmp1, 653799U, 1689999U); 740 + utmp1 = ((u64)(intlog10(utmp1) 741 + - intlog10(1690000 - utmp1) 742 + + 3355443) * 13 * 1000) >> 24; 736 743 break; 737 744 case 1: 738 - snr_lut_size = ARRAY_SIZE(qam16_snr_lut); 739 - snr_lut = qam16_snr_lut; 745 + /* 746 + * QAM-16 747 + * CNR[dB] 6 * log10((value - 370000) / (828000 - value)) + 15.7 748 + * value [371105, 827999], 15.7 / 6 = 43900382 749 + */ 750 + utmp1 = clamp(utmp1, 371105U, 827999U); 751 + utmp1 = ((u64)(intlog10(utmp1 - 370000) 752 + - intlog10(828000 - utmp1) 753 + + 43900382) * 6 * 1000) >> 24; 740 754 break; 741 755 case 2: 742 - snr_lut_size = ARRAY_SIZE(qam64_snr_lut); 743 - snr_lut = qam64_snr_lut; 756 + /* 757 + * QAM-64 758 + * CNR[dB] 8 * log10((value - 193000) / (425000 - value)) + 23.8 759 + * value [193246, 424999], 23.8 / 8 = 49912218 760 + */ 761 + utmp1 = clamp(utmp1, 193246U, 424999U); 762 + utmp1 = ((u64)(intlog10(utmp1 - 193000) 763 + - intlog10(425000 - utmp1) 764 + + 49912218) * 8 * 1000) >> 24; 744 765 break; 745 766 default: 746 - snr_lut_size = 0; 747 - tmp = 0; 767 + utmp1 = 0; 748 768 break; 749 769 } 750 770 751 - for (i = 0; i < snr_lut_size; i++) { 752 - tmp = snr_lut[i].snr * 1000; 753 - if (snr_val < snr_lut[i].val) 754 - break; 755 - } 771 + dev_dbg(&client->dev, "cnr=%u\n", utmp1); 756 772 757 - c->cnr.len = 1; 758 773 c->cnr.stat[0].scale = FE_SCALE_DECIBEL; 759 - c->cnr.stat[0].svalue = tmp; 774 + c->cnr.stat[0].svalue = utmp1; 760 775 } else { 761 - c->cnr.len = 1; 762 776 c->cnr.stat[0].scale = FE_SCALE_NOT_AVAILABLE; 763 777 } 764 778
+1 -96
drivers/media/dvb-frontends/af9033_priv.h
··· 23 23 #include <linux/math64.h> 24 24 #include <linux/regmap.h> 25 25 #include <linux/kernel.h> 26 + #include "dvb_math.h" 26 27 27 28 struct reg_val { 28 29 u32 reg; ··· 88 87 0x00, 0x2b, 0x58, 0x0b, 0x00, 0xad, 0x60, 0x2b, 0x00, 0x56, 89 88 0xb0, 0x15, 0xf4, 0x02, 0x5b, 0x01 } 90 89 }, 91 - }; 92 - 93 - /* QPSK SNR lookup table */ 94 - static const struct val_snr qpsk_snr_lut[] = { 95 - { 0x0b4771, 0 }, 96 - { 0x0c1aed, 1 }, 97 - { 0x0d0d27, 2 }, 98 - { 0x0e4d19, 3 }, 99 - { 0x0e5da8, 4 }, 100 - { 0x107097, 5 }, 101 - { 0x116975, 6 }, 102 - { 0x1252d9, 7 }, 103 - { 0x131fa4, 8 }, 104 - { 0x13d5e1, 9 }, 105 - { 0x148e53, 10 }, 106 - { 0x15358b, 11 }, 107 - { 0x15dd29, 12 }, 108 - { 0x168112, 13 }, 109 - { 0x170b61, 14 }, 110 - { 0x17a532, 15 }, 111 - { 0x180f94, 16 }, 112 - { 0x186ed2, 17 }, 113 - { 0x18b271, 18 }, 114 - { 0x18e118, 19 }, 115 - { 0x18ff4b, 20 }, 116 - { 0x190af1, 21 }, 117 - { 0x191451, 22 }, 118 - { 0xffffff, 23 }, 119 - }; 120 - 121 - /* QAM16 SNR lookup table */ 122 - static const struct val_snr qam16_snr_lut[] = { 123 - { 0x04f0d5, 0 }, 124 - { 0x05387a, 1 }, 125 - { 0x0573a4, 2 }, 126 - { 0x05a99e, 3 }, 127 - { 0x05cc80, 4 }, 128 - { 0x05eb62, 5 }, 129 - { 0x05fecf, 6 }, 130 - { 0x060b80, 7 }, 131 - { 0x062501, 8 }, 132 - { 0x064865, 9 }, 133 - { 0x069604, 10 }, 134 - { 0x06f356, 11 }, 135 - { 0x07706a, 12 }, 136 - { 0x0804d3, 13 }, 137 - { 0x089d1a, 14 }, 138 - { 0x093e3d, 15 }, 139 - { 0x09e35d, 16 }, 140 - { 0x0a7c3c, 17 }, 141 - { 0x0afaf8, 18 }, 142 - { 0x0b719d, 19 }, 143 - { 0x0bda6a, 20 }, 144 - { 0x0c0c75, 21 }, 145 - { 0x0c3f7d, 22 }, 146 - { 0x0c5e62, 23 }, 147 - { 0x0c6c31, 24 }, 148 - { 0x0c7925, 25 }, 149 - { 0xffffff, 26 }, 150 - }; 151 - 152 - /* QAM64 SNR lookup table */ 153 - static const struct val_snr qam64_snr_lut[] = { 154 - { 0x0256d0, 0 }, 155 - { 0x027a65, 1 }, 156 - { 0x029873, 2 }, 157 - { 0x02b7fe, 3 }, 158 - { 0x02cf1e, 4 }, 159 - { 0x02e234, 5 }, 160 - { 0x02f409, 6 }, 161 - { 0x030046, 7 }, 162 - { 0x030844, 8 }, 163 - { 0x030a02, 9 }, 164 - { 0x030cde, 10 }, 165 - { 0x031031, 11 }, 166 - { 0x03144c, 12 }, 167 - { 0x0315dd, 13 }, 168 - { 0x031920, 14 }, 169 - { 0x0322d0, 15 }, 170 - { 0x0339fc, 16 }, 171 - { 0x0364a1, 17 }, 172 - { 0x038bcc, 18 }, 173 - { 0x03c7d3, 19 }, 174 - { 0x0408cc, 20 }, 175 - { 0x043bed, 21 }, 176 - { 0x048061, 22 }, 177 - { 0x04be95, 23 }, 178 - { 0x04fa7d, 24 }, 179 - { 0x052405, 25 }, 180 - { 0x05570d, 26 }, 181 - { 0x059feb, 27 }, 182 - { 0x05bf38, 28 }, 183 - { 0x05f78f, 29 }, 184 - { 0x0612c3, 30 }, 185 - { 0x0626be, 31 }, 186 - { 0xffffff, 32 }, 187 90 }; 188 91 189 92 /*