From 86c34428aabebc79ac0de7f1194e6b755a6fa213 Mon Sep 17 00:00:00 2001 From: Steve Markgraf Date: Fri, 4 May 2012 23:02:29 +0200 Subject: use new E4000 tuner driver, allow manual gain Many thanks to Hoernchen for making the driver work properly and adding manual gain! Signed-off-by: Steve Markgraf --- src/tuner_e4k.c | 955 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 955 insertions(+) create mode 100644 src/tuner_e4k.c (limited to 'src/tuner_e4k.c') diff --git a/src/tuner_e4k.c b/src/tuner_e4k.c new file mode 100644 index 0000000..b530812 --- /dev/null +++ b/src/tuner_e4k.c @@ -0,0 +1,955 @@ +/* (C) 2011-2012 by Harald Welte + * + * All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +#include +#include +#include +#include +#include + +#include +#include + +#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0])) + +/* If this is defined, the limits are somewhat relaxed compared to what the + * vendor claims is possible */ +#define OUT_OF_SPEC + +#define MHZ(x) ((x)*1000*1000) +#define KHZ(x) ((x)*1000) + +uint32_t unsigned_delta(uint32_t a, uint32_t b) +{ + if (a > b) + return a - b; + else + return b - a; +} + +/* look-up table bit-width -> mask */ +static const uint8_t width2mask[] = { + 0, 1, 3, 7, 0xf, 0x1f, 0x3f, 0x7f, 0xff +}; + +/*********************************************************************** + * Register Access */ + +#if 0 +/*! \brief Write a register of the tuner chip + * \param[in] e4k reference to the tuner + * \param[in] reg number of the register + * \param[in] val value to be written + * \returns 0 on success, negative in case of error + */ +int e4k_reg_write(struct e4k_state *e4k, uint8_t reg, uint8_t val) +{ + /* FIXME */ + return 0; +} + +/*! \brief Read a register of the tuner chip + * \param[in] e4k reference to the tuner + * \param[in] reg number of the register + * \returns positive 8bit register contents on success, negative in case of error + */ +int e4k_reg_read(struct e4k_state *e4k, uint8_t reg) +{ + /* FIXME */ + return 0; +} +#endif + +/*! \brief Set or clear some (masked) bits inside a register + * \param[in] e4k reference to the tuner + * \param[in] reg number of the register + * \param[in] mask bit-mask of the value + * \param[in] val data value to be written to register + * \returns 0 on success, negative in case of error + */ +static int e4k_reg_set_mask(struct e4k_state *e4k, uint8_t reg, + uint8_t mask, uint8_t val) +{ + uint8_t tmp = e4k_reg_read(e4k, reg); + + if ((tmp & mask) == val) + return 0; + + return e4k_reg_write(e4k, reg, (tmp & ~mask) | (val & mask)); +} + +/*! \brief Write a given field inside a register + * \param[in] e4k reference to the tuner + * \param[in] field structure describing the field + * \param[in] val value to be written + * \returns 0 on success, negative in case of error + */ +static int e4k_field_write(struct e4k_state *e4k, const struct reg_field *field, uint8_t val) +{ + int rc; + uint8_t mask; + + rc = e4k_reg_read(e4k, field->reg); + if (rc < 0) + return rc; + + mask = width2mask[field->width] << field->shift; + + return e4k_reg_set_mask(e4k, field->reg, mask, val << field->shift); +} + +/*! \brief Read a given field inside a register + * \param[in] e4k reference to the tuner + * \param[in] field structure describing the field + * \returns positive value of the field, negative in case of error + */ +static int e4k_field_read(struct e4k_state *e4k, const struct reg_field *field) +{ + int rc; + + rc = e4k_reg_read(e4k, field->reg); + if (rc < 0) + return rc; + + rc = (rc >> field->shift) & width2mask[field->width]; + + return rc; +} + +/*********************************************************************** + * Filter Control */ + +static const uint32_t rf_filt_center_uhf[] = { + MHZ(360), MHZ(380), MHZ(405), MHZ(425), + MHZ(450), MHZ(475), MHZ(505), MHZ(540), + MHZ(575), MHZ(615), MHZ(670), MHZ(720), + MHZ(760), MHZ(840), MHZ(890), MHZ(970) +}; + +static const uint32_t rf_filt_center_l[] = { + MHZ(1300), MHZ(1320), MHZ(1360), MHZ(1410), + MHZ(1445), MHZ(1460), MHZ(1490), MHZ(1530), + MHZ(1560), MHZ(1590), MHZ(1640), MHZ(1660), + MHZ(1680), MHZ(1700), MHZ(1720), MHZ(1750) +}; + +static int closest_arr_idx(const uint32_t *arr, unsigned int arr_size, uint32_t freq) +{ + unsigned int i, bi = 0; + uint32_t best_delta = 0xffffffff; + + /* iterate over the array containing a list of the center + * frequencies, selecting the closest one */ + for (i = 0; i < arr_size; i++) { + uint32_t delta = unsigned_delta(freq, arr[i]); + if (delta < best_delta) { + best_delta = delta; + bi = i; + } + } + + return bi; +} + +/* return 4-bit index as to which RF filter to select */ +static int choose_rf_filter(uint32_t freq) +{ + int rc; + + if (freq < MHZ(350)) + rc = 0; + else if (freq < MHZ(1000)) + rc = closest_arr_idx(rf_filt_center_uhf, + ARRAY_SIZE(rf_filt_center_uhf), + freq); + else + rc = closest_arr_idx(rf_filt_center_l, + ARRAY_SIZE(rf_filt_center_l), + freq); + + return rc; +} + +/* \brief Automatically select apropriate RF filter based on e4k state */ +int e4k_rf_filter_set(struct e4k_state *e4k) +{ + int rc; + + rc = choose_rf_filter(e4k->vco.flo); + if (rc < 0) + return rc; + + return e4k_reg_set_mask(e4k, E4K_REG_FILT1, 0xF, rc); +} + +/* Mixer Filter */ +static const uint32_t mix_filter_bw[] = { + KHZ(27000), KHZ(27000), KHZ(27000), KHZ(27000), + KHZ(27000), KHZ(27000), KHZ(27000), KHZ(27000), + KHZ(4600), KHZ(4200), KHZ(3800), KHZ(3400), + KHZ(3300), KHZ(2700), KHZ(2300), KHZ(1900) +}; + +/* IF RC Filter */ +static const uint32_t ifrc_filter_bw[] = { + KHZ(21400), KHZ(21000), KHZ(17600), KHZ(14700), + KHZ(12400), KHZ(10600), KHZ(9000), KHZ(7700), + KHZ(6400), KHZ(5300), KHZ(4400), KHZ(3400), + KHZ(2600), KHZ(1800), KHZ(1200), KHZ(1000) +}; + +/* IF Channel Filter */ +static const uint32_t ifch_filter_bw[] = { + KHZ(5500), KHZ(5300), KHZ(5000), KHZ(4800), + KHZ(4600), KHZ(4400), KHZ(4300), KHZ(4100), + KHZ(3900), KHZ(3800), KHZ(3700), KHZ(3600), + KHZ(3400), KHZ(3300), KHZ(3200), KHZ(3100), + KHZ(3000), KHZ(2950), KHZ(2900), KHZ(2800), + KHZ(2750), KHZ(2700), KHZ(2600), KHZ(2550), + KHZ(2500), KHZ(2450), KHZ(2400), KHZ(2300), + KHZ(2280), KHZ(2240), KHZ(2200), KHZ(2150) +}; + +static const uint32_t *if_filter_bw[] = { + mix_filter_bw, + ifch_filter_bw, + ifrc_filter_bw, +}; + +static const uint32_t if_filter_bw_len[] = { + ARRAY_SIZE(mix_filter_bw), + ARRAY_SIZE(ifch_filter_bw), + ARRAY_SIZE(ifrc_filter_bw), +}; + +static const struct reg_field if_filter_fields[] = { + { + E4K_REG_FILT2, 4, 4, + }, + { + E4K_REG_FILT3, 0, 5, + }, + { + E4K_REG_FILT2, 0, 4, + } +}; + +static int find_if_bw(enum e4k_if_filter filter, uint32_t bw) +{ + if (filter >= ARRAY_SIZE(if_filter_bw)) + return -EINVAL; + + return closest_arr_idx(if_filter_bw[filter], + if_filter_bw_len[filter], bw); +} + +/*! \brief Set the filter band-width of any of the IF filters + * \param[in] e4k reference to the tuner chip + * \param[in] filter filter to be configured + * \param[in] bandwidth bandwidth to be configured + * \returns positive actual filter band-width, negative in case of error + */ +int e4k_if_filter_bw_set(struct e4k_state *e4k, enum e4k_if_filter filter, + uint32_t bandwidth) +{ + int bw_idx; + const struct reg_field *field; + + if (filter >= ARRAY_SIZE(if_filter_bw)) + return -EINVAL; + + bw_idx = find_if_bw(filter, bandwidth); + + field = &if_filter_fields[filter]; + + return e4k_field_write(e4k, field, bw_idx); +} + +/*! \brief Enables / Disables the channel filter + * \param[in] e4k reference to the tuner chip + * \param[in] on 1=filter enabled, 0=filter disabled + * \returns 0 success, negative errors + */ +int e4k_if_filter_chan_enable(struct e4k_state *e4k, int on) +{ + return e4k_reg_set_mask(e4k, E4K_REG_FILT3, E4K_FILT3_DISABLE, + on ? 0 : E4K_FILT3_DISABLE); +} + +int e4k_if_filter_bw_get(struct e4k_state *e4k, enum e4k_if_filter filter) +{ + const uint32_t *arr; + int rc; + const struct reg_field *field; + + if (filter >= ARRAY_SIZE(if_filter_bw)) + return -EINVAL; + + field = &if_filter_fields[filter]; + + rc = e4k_field_read(e4k, field); + if (rc < 0) + return rc; + + arr = if_filter_bw[filter]; + + return arr[rc]; +} + + +/*********************************************************************** + * Frequency Control */ + +#define E4K_FVCO_MIN_KHZ 2600000 /* 2.6 GHz */ +#define E4K_FVCO_MAX_KHZ 3900000 /* 3.9 GHz */ +#define E4K_PLL_Y 65536 + +#ifdef OUT_OF_SPEC +#define E4K_FLO_MIN_MHZ 50 +#define E4K_FLO_MAX_MHZ 2200UL +#else +#define E4K_FLO_MIN_MHZ 64 +#define E4K_FLO_MAX_MHZ 1700 +#endif + +struct pll_settings { + uint32_t freq; + uint8_t reg_synth7; + uint8_t mult; +}; + +static const struct pll_settings pll_vars[] = { + {KHZ(72400), (1 << 3) | 7, 48}, + {KHZ(81200), (1 << 3) | 6, 40}, + {KHZ(108300), (1 << 3) | 5, 32}, + {KHZ(162500), (1 << 3) | 4, 24}, + {KHZ(216600), (1 << 3) | 3, 16}, + {KHZ(325000), (1 << 3) | 2, 12}, + {KHZ(350000), (1 << 3) | 1, 8}, + {KHZ(432000), (0 << 3) | 3, 8}, + {KHZ(667000), (0 << 3) | 2, 6}, + {KHZ(1200000), (0 << 3) | 1, 4} +}; + +static int is_fvco_valid(uint32_t fvco_z) +{ + /* check if the resulting fosc is valid */ + if (fvco_z/1000 < E4K_FVCO_MIN_KHZ || + fvco_z/1000 > E4K_FVCO_MAX_KHZ) { + fprintf(stderr, "Fvco %u invalid\n", fvco_z); + return 0; + } + + return 1; +} + +static int is_fosc_valid(uint32_t fosc) +{ + if (fosc < MHZ(16) || fosc > MHZ(30)) { + fprintf(stderr, "Fosc %u invalid\n", fosc); + return 0; + } + + return 1; +} + +static int is_z_valid(uint32_t z) +{ + if (z > 255) { + fprintf(stderr, "Z %u invalid\n", z); + return 0; + } + + return 1; +} + +/*! \brief Determine if 3-phase mixing shall be used or not */ +static int use_3ph_mixing(uint32_t flo) +{ + /* this is a magic number somewhre between VHF and UHF */ + if (flo < MHZ(350)) + return 1; + + return 0; +} + +/* \brief compute Fvco based on Fosc, Z and X + * \returns positive value (Fvco in Hz), 0 in case of error */ +static uint64_t compute_fvco(uint32_t f_osc, uint8_t z, uint16_t x) +{ + uint64_t fvco_z, fvco_x, fvco; + + /* We use the following transformation in order to + * handle the fractional part with integer arithmetic: + * Fvco = Fosc * (Z + X/Y) <=> Fvco = Fosc * Z + (Fosc * X)/Y + * This avoids X/Y = 0. However, then we would overflow a 32bit + * integer, as we cannot hold e.g. 26 MHz * 65536 either. + */ + fvco_z = (uint64_t)f_osc * z; + +#if 0 + if (!is_fvco_valid(fvco_z)) + return 0; +#endif + + fvco_x = ((uint64_t)f_osc * x) / E4K_PLL_Y; + + fvco = fvco_z + fvco_x; + + return fvco; +} + +static int compute_flo(uint32_t f_osc, uint8_t z, uint16_t x, uint8_t r) +{ + uint64_t fvco = compute_fvco(f_osc, z, x); + if (fvco == 0) + return -EINVAL; + + return fvco / r; +} + +static int e4k_band_set(struct e4k_state *e4k, enum e4k_band band) +{ + int rc; + + switch (band) { + case E4K_BAND_VHF2: + case E4K_BAND_VHF3: + case E4K_BAND_UHF: + e4k_reg_write(e4k, E4K_REG_BIAS, 3); + break; + case E4K_BAND_L: + e4k_reg_write(e4k, E4K_REG_BIAS, 0); + break; + } + + rc = e4k_reg_set_mask(e4k, E4K_REG_SYNTH1, 0x06, band << 1); + if (rc >= 0) + e4k->band = band; + + return rc; +} + +/*! \brief Compute PLL parameters for givent target frequency + * \param[out] oscp Oscillator parameters, if computation successful + * \param[in] fosc Clock input frequency applied to the chip (Hz) + * \param[in] intended_flo target tuning frequency (Hz) + * \returns actual PLL frequency, as close as possible to intended_flo, + * negative in case of error + */ +int e4k_compute_pll_params(struct e4k_pll_params *oscp, uint32_t fosc, uint32_t intended_flo) +{ + uint32_t i; + uint8_t r = 2; + uint64_t intended_fvco, remainder; + uint64_t z = 0; + uint32_t x; + int flo; + int three_phase_mixing = 0; + oscp->r_idx = 0; + + if (!is_fosc_valid(fosc)) + return -EINVAL; + + for(i = 0; i < ARRAY_SIZE(pll_vars); ++i) { + if(intended_flo < pll_vars[i].freq) { + three_phase_mixing = (pll_vars[i].reg_synth7 & 0x08) ? 1 : 0; + oscp->r_idx = pll_vars[i].reg_synth7; + r = pll_vars[i].mult; + break; + } + } + + //fprintf(stderr, "Fint=%u, R=%u\n", intended_flo, r); + + /* flo(max) = 1700MHz, R(max) = 48, we need 64bit! */ + intended_fvco = (uint64_t)intended_flo * r; + + /* compute integral component of multiplier */ + z = intended_fvco / fosc; + + /* compute fractional part. this will not overflow, + * as fosc(max) = 30MHz and z(max) = 255 */ + remainder = intended_fvco - (fosc * z); + /* remainder(max) = 30MHz, E4K_PLL_Y = 65536 -> 64bit! */ + x = (remainder * E4K_PLL_Y) / fosc; + /* x(max) as result of this computation is 65536 */ + + flo = compute_flo(fosc, z, x, r); + + oscp->fosc = fosc; + oscp->flo = flo; + oscp->intended_flo = intended_flo; + oscp->r = r; +// oscp->r_idx = pll_vars[i].reg_synth7 & 0x0; + oscp->threephase = three_phase_mixing; + oscp->x = x; + oscp->z = z; + + return flo; +} + +int e4k_tune_params(struct e4k_state *e4k, struct e4k_pll_params *p) +{ + uint8_t val; + + /* program R + 3phase/2phase */ + e4k_reg_write(e4k, E4K_REG_SYNTH7, p->r_idx); + /* program Z */ + e4k_reg_write(e4k, E4K_REG_SYNTH3, p->z); + /* program X */ + e4k_reg_write(e4k, E4K_REG_SYNTH4, p->x & 0xff); + e4k_reg_write(e4k, E4K_REG_SYNTH5, p->x >> 8); + + /* we're in auto calibration mode, so there's no need to trigger it */ + + memcpy(&e4k->vco, p, sizeof(e4k->vco)); + + /* set the band */ + if (e4k->vco.flo < MHZ(140)) + e4k_band_set(e4k, E4K_BAND_VHF2); + else if (e4k->vco.flo < MHZ(350)) + e4k_band_set(e4k, E4K_BAND_VHF3); + else if (e4k->vco.flo < MHZ(1000)) + e4k_band_set(e4k, E4K_BAND_UHF); + else + e4k_band_set(e4k, E4K_BAND_L); + + /* select and set proper RF filter */ + e4k_rf_filter_set(e4k); + + return e4k->vco.flo; +} + +/*! \brief High-level tuning API, just specify frquency + * + * This function will compute matching PLL parameters, program them into the + * hardware and set the band as well as RF filter. + * + * \param[in] e4k reference to tuner + * \param[in] freq frequency in Hz + * \returns actual tuned frequency, negative in case of error + */ +int e4k_tune_freq(struct e4k_state *e4k, uint32_t freq) +{ + int rc, i; + struct e4k_pll_params p; + + /* determine PLL parameters */ + rc = e4k_compute_pll_params(&p, e4k->vco.fosc, freq); + if (rc < 0) + return rc; + + /* actually tune to those parameters */ + rc = e4k_tune_params(e4k, &p); + + /* check PLL lock */ + rc = e4k_reg_read(e4k, E4K_REG_SYNTH1); + if (!(rc & 0x01)) { + printf("[E4K] PLL not locked!\n"); + return -1; + } + + return 0; +} + +/*********************************************************************** + * Gain Control */ + +static const int8_t if_stage1_gain[] = { + -3, 6 +}; + +static const int8_t if_stage23_gain[] = { + 0, 3, 6, 9 +}; + +static const int8_t if_stage4_gain[] = { + 0, 1, 2, 2 +}; + +static const int8_t if_stage56_gain[] = { + 3, 6, 9, 12, 15, 15, 15, 15 +}; + +static const int8_t *if_stage_gain[] = { + 0, + if_stage1_gain, + if_stage23_gain, + if_stage23_gain, + if_stage4_gain, + if_stage56_gain, + if_stage56_gain +}; + +static const uint8_t if_stage_gain_len[] = { + 0, + ARRAY_SIZE(if_stage1_gain), + ARRAY_SIZE(if_stage23_gain), + ARRAY_SIZE(if_stage23_gain), + ARRAY_SIZE(if_stage4_gain), + ARRAY_SIZE(if_stage56_gain), + ARRAY_SIZE(if_stage56_gain) +}; + +static const struct reg_field if_stage_gain_regs[] = { + { E4K_REG_GAIN3, 0, 1 }, + { E4K_REG_GAIN3, 1, 2 }, + { E4K_REG_GAIN3, 3, 2 }, + { E4K_REG_GAIN3, 5, 2 }, + { E4K_REG_GAIN4, 0, 3 }, + { E4K_REG_GAIN4, 3, 3 } +}; + +static const int32_t lnagain[] = { + -50, 0, + -25, 1, + 0, 4, + 25, 5, + 50, 6, + 75, 7, + 100, 8, + 125, 9, + 150, 10, + 175, 11, + 200, 12, + 250, 13, + 300, 14, +}; + +static const int32_t enhgain[] = { + 10, 30, 50, 70 +}; + +int e4k_set_lna_gain(struct e4k_state *e4k, int32_t gain) +{ + uint32_t i; + for(i = 0; i < ARRAY_SIZE(lnagain)/2; ++i) { + if(lnagain[i*2] == gain) { + e4k_reg_set_mask(e4k, E4K_REG_GAIN1, 0xf, lnagain[i*2+1]); + return gain; + } + } + return -EINVAL; +} + +int e4k_set_enh_gain(struct e4k_state *e4k, int32_t gain) +{ + uint32_t i; + for(i = 0; i < ARRAY_SIZE(enhgain); ++i) { + if(enhgain[i] == gain) { + e4k_reg_set_mask(e4k, E4K_REG_AGC11, 0x7, E4K_AGC11_LNA_GAIN_ENH | (i << 1)); + return gain; + } + } + e4k_reg_set_mask(e4k, E4K_REG_AGC11, 0x7, 0); + return 0; +} + +int e4k_enable_manual_gain(struct e4k_state *e4k, uint8_t manual) +{ + if (manual) { + /* Set LNA mode to manual */ + e4k_reg_set_mask(e4k, E4K_REG_AGC1, E4K_AGC1_MOD_MASK, E4K_AGC_MOD_SERIAL); + + /* Set Mixer Gain Control to manual */ + e4k_reg_set_mask(e4k, E4K_REG_AGC7, E4K_AGC7_MIX_GAIN_AUTO, 0); + } else { + /* Set LNA mode to auto */ + e4k_reg_set_mask(e4k, E4K_REG_AGC1, E4K_AGC1_MOD_MASK, E4K_AGC_MOD_IF_SERIAL_LNA_AUTON); + /* Set Mixer Gain Control to auto */ + e4k_reg_set_mask(e4k, E4K_REG_AGC7, E4K_AGC7_MIX_GAIN_AUTO, 1); + + e4k_reg_set_mask(e4k, E4K_REG_AGC11, 0x7, 0); + } + + return 0; +} + +static int find_stage_gain(uint8_t stage, int8_t val) +{ + const int8_t *arr; + int i; + + if (stage >= ARRAY_SIZE(if_stage_gain)) + return -EINVAL; + + arr = if_stage_gain[stage]; + + for (i = 0; i < if_stage_gain_len[stage]; i++) { + if (arr[i] == val) + return i; + } + return -EINVAL; +} + +/*! \brief Set the gain of one of the IF gain stages + * \param[e4k] handle to the tuner chip + * \param [stage] numbere of the stage (1..6) + * \param [value] gain value in dBm + * \returns 0 on success, negative in case of error + */ +int e4k_if_gain_set(struct e4k_state *e4k, uint8_t stage, int8_t value) +{ + int rc; + uint8_t mask; + const struct reg_field *field; + + rc = find_stage_gain(stage, value); + if (rc < 0) + return rc; + + /* compute the bit-mask for the given gain field */ + field = &if_stage_gain_regs[stage]; + mask = width2mask[field->width] << field->shift; + + return e4k_reg_set_mask(e4k, field->reg, mask, rc << field->shift); +} + +int e4k_mixer_gain_set(struct e4k_state *e4k, int8_t value) +{ + uint8_t bit; + + switch (value) { + case 4: + bit = 0; + break; + case 12: + bit = 1; + break; + default: + return -EINVAL; + } + + return e4k_reg_set_mask(e4k, E4K_REG_GAIN2, 1, bit); +} + +int e4k_commonmode_set(struct e4k_state *e4k, int8_t value) +{ + if(value < 0) + return -EINVAL; + else if(value > 7) + return -EINVAL; + + return e4k_reg_set_mask(e4k, E4K_REG_DC7, 7, value); +} + +/*********************************************************************** + * DC Offset */ + +int e4k_manual_dc_offset(struct e4k_state *e4k, int8_t iofs, int8_t irange, int8_t qofs, int8_t qrange) +{ + int res; + + if((iofs < 0x00) || (iofs > 0x3f)) + return -EINVAL; + if((irange < 0x00) || (irange > 0x03)) + return -EINVAL; + if((qofs < 0x00) || (qofs > 0x3f)) + return -EINVAL; + if((qrange < 0x00) || (qrange > 0x03)) + return -EINVAL; + + res = e4k_reg_set_mask(e4k, E4K_REG_DC2, 0x3f, iofs); + if(res < 0) + return res; + + res = e4k_reg_set_mask(e4k, E4K_REG_DC3, 0x3f, qofs); + if(res < 0) + return res; + + res = e4k_reg_set_mask(e4k, E4K_REG_DC4, 0x33, (qrange << 4) | irange); + return res; +} + +/*! \brief Perform a DC offset calibration right now + * \param[e4k] handle to the tuner chip + */ +int e4k_dc_offset_calibrate(struct e4k_state *e4k) +{ + /* make sure the DC range detector is enabled */ + e4k_reg_set_mask(e4k, E4K_REG_DC5, E4K_DC5_RANGE_DET_EN, E4K_DC5_RANGE_DET_EN); + + return e4k_reg_write(e4k, E4K_REG_DC1, 0x01); +} + + +static const int8_t if_gains_max[] = { + 0, 6, 9, 9, 2, 15, 15 +}; + +struct gain_comb { + int8_t mixer_gain; + int8_t if1_gain; + uint8_t reg; +}; + +static const struct gain_comb dc_gain_comb[] = { + { 4, -3, 0x50 }, + { 4, 6, 0x51 }, + { 12, -3, 0x52 }, + { 12, 6, 0x53 }, +}; + +#define TO_LUT(offset, range) (offset | (range << 6)) + +int e4k_dc_offset_gen_table(struct e4k_state *e4k) +{ + uint32_t i; + + /* FIXME: read ont current gain values and write them back + * before returning to the caller */ + + /* disable auto mixer gain */ + e4k_reg_set_mask(e4k, E4K_REG_AGC7, E4K_AGC7_MIX_GAIN_AUTO, 0); + + /* set LNA/IF gain to full manual */ + e4k_reg_set_mask(e4k, E4K_REG_AGC1, E4K_AGC1_MOD_MASK, + E4K_AGC_MOD_SERIAL); + + /* set all 'other' gains to maximum */ + for (i = 2; i <= 6; i++) + e4k_if_gain_set(e4k, i, if_gains_max[i]); + + /* iterate over all mixer + if_stage_1 gain combinations */ + for (i = 0; i < ARRAY_SIZE(dc_gain_comb); i++) { + uint8_t offs_i, offs_q, range, range_i, range_q; + + /* set the combination of mixer / if1 gain */ + e4k_mixer_gain_set(e4k, dc_gain_comb[i].mixer_gain); + e4k_if_gain_set(e4k, 1, dc_gain_comb[i].if1_gain); + + /* perform actual calibration */ + e4k_dc_offset_calibrate(e4k); + + /* extract I/Q offset and range values */ + offs_i = e4k_reg_read(e4k, E4K_REG_DC2) & 0x3f; + offs_q = e4k_reg_read(e4k, E4K_REG_DC3) & 0x3f; + range = e4k_reg_read(e4k, E4K_REG_DC4); + range_i = range & 0x3; + range_q = (range >> 4) & 0x3; + + printf("Table %u I=%u/%u, Q=%u/%u\n", + i, range_i, offs_i, range_q, offs_q); + + /* write into the table */ + e4k_reg_write(e4k, dc_gain_comb[i].reg, + TO_LUT(offs_q, range_q)); + e4k_reg_write(e4k, dc_gain_comb[i].reg + 0x10, + TO_LUT(offs_i, range_i)); + } + + return 0; +} + +/*********************************************************************** + * Initialization */ + +static int magic_init(struct e4k_state *e4k) +{ + e4k_reg_write(e4k, 0x7e, 0x01); + e4k_reg_write(e4k, 0x7f, 0xfe); + e4k_reg_write(e4k, 0x82, 0x00); + e4k_reg_write(e4k, 0x86, 0x50); /* polarity A */ + e4k_reg_write(e4k, 0x87, 0x20); + e4k_reg_write(e4k, 0x88, 0x01); + e4k_reg_write(e4k, 0x9f, 0x7f); + e4k_reg_write(e4k, 0xa0, 0x07); + + return 0; +} + +/*! \brief Initialize the E4K tuner + */ +int e4k_init(struct e4k_state *e4k) +{ + /* make a dummy i2c read or write command, will not be ACKed! */ + e4k_reg_read(e4k, 0); + + /* Make sure we reset everything and clear POR indicator */ + e4k_reg_write(e4k, E4K_REG_MASTER1, + E4K_MASTER1_RESET | + E4K_MASTER1_NORM_STBY | + E4K_MASTER1_POR_DET + ); + + /* Configure clock input */ + e4k_reg_write(e4k, E4K_REG_CLK_INP, 0x00); + + /* Disable clock output */ + e4k_reg_write(e4k, E4K_REG_REF_CLK, 0x00); + e4k_reg_write(e4k, E4K_REG_CLKOUT_PWDN, 0x96); + + /* Write some magic values into registers */ + magic_init(e4k); +#if 0 + /* Set common mode voltage a bit higher for more margin 850 mv */ + e4k_commonmode_set(e4k, 4); + + /* Initialize DC offset lookup tables */ + e4k_dc_offset_gen_table(e4k); + + /* Enable time variant DC correction */ + e4k_reg_write(e4k, E4K_REG_DCTIME1, 0x01); + e4k_reg_write(e4k, E4K_REG_DCTIME2, 0x01); +#endif + + /* Set LNA mode to manual */ + e4k_reg_write(e4k, E4K_REG_AGC4, 0x10); /* High threshold */ + e4k_reg_write(e4k, E4K_REG_AGC5, 0x04); /* Low threshold */ + e4k_reg_write(e4k, E4K_REG_AGC6, 0x1a); /* LNA calib + loop rate */ + + e4k_reg_set_mask(e4k, E4K_REG_AGC1, E4K_AGC1_MOD_MASK, + E4K_AGC_MOD_SERIAL); + + /* Set Mixer Gain Control to manual */ + e4k_reg_set_mask(e4k, E4K_REG_AGC7, E4K_AGC7_MIX_GAIN_AUTO, 0); + +#if 0 + /* Enable LNA Gain enhancement */ + e4k_reg_set_mask(e4k, E4K_REG_AGC11, 0x7, + E4K_AGC11_LNA_GAIN_ENH | (2 << 1)); + + /* Enable automatic IF gain mode switching */ + e4k_reg_set_mask(e4k, E4K_REG_AGC8, 0x1, E4K_AGC8_SENS_LIN_AUTO); +#endif + + /* Use auto-gain as default */ + e4k_enable_manual_gain(e4k, 0); + + /* Select moderate gain levels */ + e4k_if_gain_set(e4k, 1, 6); + e4k_if_gain_set(e4k, 2, 0); + e4k_if_gain_set(e4k, 3, 0); + e4k_if_gain_set(e4k, 4, 0); + e4k_if_gain_set(e4k, 5, 9); + e4k_if_gain_set(e4k, 6, 9); + + /* Set the most narrow filter we can possibly use */ + e4k_if_filter_bw_set(e4k, E4K_IF_FILTER_MIX, KHZ(1900)); + e4k_if_filter_bw_set(e4k, E4K_IF_FILTER_RC, KHZ(1000)); + e4k_if_filter_bw_set(e4k, E4K_IF_FILTER_CHAN, KHZ(2150)); + e4k_if_filter_chan_enable(e4k, 1); + + /* Disable time variant DC correction and LUT */ + e4k_reg_set_mask(e4k, E4K_REG_DC5, 0x03, 0); + e4k_reg_set_mask(e4k, E4K_REG_DCTIME1, 0x03, 0); + e4k_reg_set_mask(e4k, E4K_REG_DCTIME2, 0x03, 0); + + return 0; +} -- cgit v1.2.3