// SPDX-License-Identifier: GPL-2.0 /* * This file is the ADC part of the STM32 DFSDM driver * * Copyright (C) 2017, STMicroelectronics - All Rights Reserved * Author: Arnaud Pouliquen . */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "stm32-dfsdm.h" #define DFSDM_DMA_BUFFER_SIZE (4 * PAGE_SIZE) /* Conversion timeout */ #define DFSDM_TIMEOUT_US 100000 #define DFSDM_TIMEOUT (msecs_to_jiffies(DFSDM_TIMEOUT_US / 1000)) /* Oversampling attribute default */ #define DFSDM_DEFAULT_OVERSAMPLING 100 /* Oversampling max values */ #define DFSDM_MAX_INT_OVERSAMPLING 256 #define DFSDM_MAX_FL_OVERSAMPLING 1024 /* Limit filter output resolution to 31 bits. (i.e. sample range is +/-2^30) */ #define DFSDM_DATA_MAX BIT(30) /* * Data are output as two's complement data in a 24 bit field. * Data from filters are in the range +/-2^(n-1) * 2^(n-1) maximum positive value cannot be coded in 2's complement n bits * An extra bit is required to avoid wrap-around of the binary code for 2^(n-1) * So, the resolution of samples from filter is actually limited to 23 bits */ #define DFSDM_DATA_RES 24 /* Filter configuration */ #define DFSDM_CR1_CFG_MASK (DFSDM_CR1_RCH_MASK | DFSDM_CR1_RCONT_MASK | \ DFSDM_CR1_RSYNC_MASK | DFSDM_CR1_JSYNC_MASK | \ DFSDM_CR1_JSCAN_MASK) enum sd_converter_type { DFSDM_AUDIO, DFSDM_IIO, }; struct stm32_dfsdm_dev_data { int type; int (*init)(struct device *dev, struct iio_dev *indio_dev); unsigned int num_channels; const struct regmap_config *regmap_cfg; }; struct stm32_dfsdm_adc { struct stm32_dfsdm *dfsdm; const struct stm32_dfsdm_dev_data *dev_data; unsigned int fl_id; unsigned int nconv; unsigned long smask; /* ADC specific */ unsigned int oversamp; struct iio_hw_consumer *hwc; struct iio_backend **backend; struct completion completion; u32 *buffer; /* Audio specific */ unsigned int spi_freq; /* SPI bus clock frequency */ unsigned int sample_freq; /* Sample frequency after filter decimation */ int (*cb)(const void *data, size_t size, void *cb_priv); void *cb_priv; /* DMA */ u8 *rx_buf; unsigned int bufi; /* Buffer current position */ unsigned int buf_sz; /* Buffer size */ struct dma_chan *dma_chan; dma_addr_t dma_buf; }; struct stm32_dfsdm_str2field { const char *name; unsigned int val; }; /* DFSDM channel serial interface type */ static const struct stm32_dfsdm_str2field stm32_dfsdm_chan_type[] = { { "SPI_R", 0 }, /* SPI with data on rising edge */ { "SPI_F", 1 }, /* SPI with data on falling edge */ { "MANCH_R", 2 }, /* Manchester codec, rising edge = logic 0 */ { "MANCH_F", 3 }, /* Manchester codec, falling edge = logic 1 */ {}, }; /* DFSDM channel clock source */ static const struct stm32_dfsdm_str2field stm32_dfsdm_chan_src[] = { /* External SPI clock (CLKIN x) */ { "CLKIN", DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL }, /* Internal SPI clock (CLKOUT) */ { "CLKOUT", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL }, /* Internal SPI clock divided by 2 (falling edge) */ { "CLKOUT_F", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING }, /* Internal SPI clock divided by 2 (falling edge) */ { "CLKOUT_R", DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING }, {}, }; static int stm32_dfsdm_str2val(const char *str, const struct stm32_dfsdm_str2field *list) { const struct stm32_dfsdm_str2field *p = list; for (p = list; p && p->name; p++) if (!strcmp(p->name, str)) return p->val; return -EINVAL; } /** * struct stm32_dfsdm_trig_info - DFSDM trigger info * @name: name of the trigger, corresponding to its source * @jextsel: trigger signal selection */ struct stm32_dfsdm_trig_info { const char *name; unsigned int jextsel; }; /* hardware injected trigger enable, edge selection */ enum stm32_dfsdm_jexten { STM32_DFSDM_JEXTEN_DISABLED, STM32_DFSDM_JEXTEN_RISING_EDGE, STM32_DFSDM_JEXTEN_FALLING_EDGE, STM32_DFSDM_EXTEN_BOTH_EDGES, }; static const struct stm32_dfsdm_trig_info stm32_dfsdm_trigs[] = { { TIM1_TRGO, 0 }, { TIM1_TRGO2, 1 }, { TIM8_TRGO, 2 }, { TIM8_TRGO2, 3 }, { TIM3_TRGO, 4 }, { TIM4_TRGO, 5 }, { TIM16_OC1, 6 }, { TIM6_TRGO, 7 }, { TIM7_TRGO, 8 }, { LPTIM1_OUT, 26 }, { LPTIM2_OUT, 27 }, { LPTIM3_OUT, 28 }, {}, }; static int stm32_dfsdm_get_jextsel(struct iio_dev *indio_dev, struct iio_trigger *trig) { int i; /* lookup triggers registered by stm32 timer trigger driver */ for (i = 0; stm32_dfsdm_trigs[i].name; i++) { /** * Checking both stm32 timer trigger type and trig name * should be safe against arbitrary trigger names. */ if ((is_stm32_timer_trigger(trig) || is_stm32_lptim_trigger(trig)) && !strcmp(stm32_dfsdm_trigs[i].name, trig->name)) { return stm32_dfsdm_trigs[i].jextsel; } } return -EINVAL; } static int stm32_dfsdm_compute_osrs(struct stm32_dfsdm_filter *fl, unsigned int fast, unsigned int oversamp) { unsigned int i, d, fosr, iosr; u64 res, max; int bits, shift; unsigned int m = 1; /* multiplication factor */ unsigned int p = fl->ford; /* filter order (ford) */ struct stm32_dfsdm_filter_osr *flo = &fl->flo[fast]; pr_debug("Requested oversampling: %d\n", oversamp); /* * This function tries to compute filter oversampling and integrator * oversampling, base on oversampling ratio requested by user. * * Decimation d depends on the filter order and the oversampling ratios. * ford: filter order * fosr: filter over sampling ratio * iosr: integrator over sampling ratio */ if (fl->ford == DFSDM_FASTSINC_ORDER) { m = 2; p = 2; } /* * Look for filter and integrator oversampling ratios which allows * to maximize data output resolution. */ for (fosr = 1; fosr <= DFSDM_MAX_FL_OVERSAMPLING; fosr++) { for (iosr = 1; iosr <= DFSDM_MAX_INT_OVERSAMPLING; iosr++) { if (fast) d = fosr * iosr; else if (fl->ford == DFSDM_FASTSINC_ORDER) d = fosr * (iosr + 3) + 2; else d = fosr * (iosr - 1 + p) + p; if (d > oversamp) break; else if (d != oversamp) continue; /* * Check resolution (limited to signed 32 bits) * res <= 2^31 * Sincx filters: * res = m * fosr^p x iosr (with m=1, p=ford) * FastSinc filter * res = m * fosr^p x iosr (with m=2, p=2) */ res = fosr; for (i = p - 1; i > 0; i--) { res = res * (u64)fosr; if (res > DFSDM_DATA_MAX) break; } if (res > DFSDM_DATA_MAX) continue; res = res * (u64)m * (u64)iosr; if (res > DFSDM_DATA_MAX) continue; if (res >= flo->res) { flo->res = res; flo->fosr = fosr; flo->iosr = iosr; bits = fls(flo->res); /* 8 LBSs in data register contain chan info */ max = flo->res << 8; /* if resolution is not a power of two */ if (flo->res > BIT(bits - 1)) bits++; else max--; shift = DFSDM_DATA_RES - bits; /* * Compute right/left shift * Right shift is performed by hardware * when transferring samples to data register. * Left shift is done by software on buffer */ if (shift > 0) { /* Resolution is lower than 24 bits */ flo->rshift = 0; flo->lshift = shift; } else { /* * If resolution is 24 bits or more, * max positive value may be ambiguous * (equal to max negative value as sign * bit is dropped). * Reduce resolution to 23 bits (rshift) * to keep the sign on bit 23 and treat * saturation before rescaling on 24 * bits (lshift). */ flo->rshift = 1 - shift; flo->lshift = 1; max >>= flo->rshift; } flo->max = (s32)max; flo->bits = bits; pr_debug("fast %d, fosr %d, iosr %d, res 0x%llx/%d bits, rshift %d, lshift %d\n", fast, flo->fosr, flo->iosr, flo->res, bits, flo->rshift, flo->lshift); } } } if (!flo->res) return -EINVAL; return 0; } static int stm32_dfsdm_compute_all_osrs(struct iio_dev *indio_dev, unsigned int oversamp) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; int ret0, ret1; memset(&fl->flo[0], 0, sizeof(fl->flo[0])); memset(&fl->flo[1], 0, sizeof(fl->flo[1])); ret0 = stm32_dfsdm_compute_osrs(fl, 0, oversamp); ret1 = stm32_dfsdm_compute_osrs(fl, 1, oversamp); if (ret0 < 0 && ret1 < 0) { dev_err(&indio_dev->dev, "Filter parameters not found: errors %d/%d\n", ret0, ret1); return -EINVAL; } return 0; } static int stm32_dfsdm_start_channel(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; const struct iio_chan_spec *chan; unsigned int bit; int ret; for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { chan = indio_dev->channels + bit; ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(chan->channel), DFSDM_CHCFGR1_CHEN_MASK, DFSDM_CHCFGR1_CHEN(1)); if (ret < 0) return ret; } return 0; } static void stm32_dfsdm_stop_channel(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; const struct iio_chan_spec *chan; unsigned int bit; for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { chan = indio_dev->channels + bit; regmap_update_bits(regmap, DFSDM_CHCFGR1(chan->channel), DFSDM_CHCFGR1_CHEN_MASK, DFSDM_CHCFGR1_CHEN(0)); } } static int stm32_dfsdm_chan_configure(struct stm32_dfsdm *dfsdm, struct stm32_dfsdm_channel *ch) { unsigned int id = ch->id; struct regmap *regmap = dfsdm->regmap; int ret; ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id), DFSDM_CHCFGR1_SITP_MASK, DFSDM_CHCFGR1_SITP(ch->type)); if (ret < 0) return ret; ret = regmap_update_bits(regmap, DFSDM_CHCFGR1(id), DFSDM_CHCFGR1_SPICKSEL_MASK, DFSDM_CHCFGR1_SPICKSEL(ch->src)); if (ret < 0) return ret; return regmap_update_bits(regmap, DFSDM_CHCFGR1(id), DFSDM_CHCFGR1_CHINSEL_MASK, DFSDM_CHCFGR1_CHINSEL(ch->alt_si)); } static int stm32_dfsdm_start_filter(struct stm32_dfsdm_adc *adc, unsigned int fl_id, struct iio_trigger *trig) { struct stm32_dfsdm *dfsdm = adc->dfsdm; int ret; /* Enable filter */ ret = regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(1)); if (ret < 0) return ret; /* Nothing more to do for injected (scan mode/triggered) conversions */ if (adc->nconv > 1 || trig) return 0; /* Software start (single or continuous) regular conversion */ return regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), DFSDM_CR1_RSWSTART_MASK, DFSDM_CR1_RSWSTART(1)); } static void stm32_dfsdm_stop_filter(struct stm32_dfsdm *dfsdm, unsigned int fl_id) { /* Disable conversion */ regmap_update_bits(dfsdm->regmap, DFSDM_CR1(fl_id), DFSDM_CR1_DFEN_MASK, DFSDM_CR1_DFEN(0)); } static int stm32_dfsdm_filter_set_trig(struct iio_dev *indio_dev, unsigned int fl_id, struct iio_trigger *trig) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; u32 jextsel = 0, jexten = STM32_DFSDM_JEXTEN_DISABLED; int ret; if (trig) { ret = stm32_dfsdm_get_jextsel(indio_dev, trig); if (ret < 0) return ret; /* set trigger source and polarity (default to rising edge) */ jextsel = ret; jexten = STM32_DFSDM_JEXTEN_RISING_EDGE; } ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_JEXTSEL_MASK | DFSDM_CR1_JEXTEN_MASK, DFSDM_CR1_JEXTSEL(jextsel) | DFSDM_CR1_JEXTEN(jexten)); if (ret < 0) return ret; return 0; } static int stm32_dfsdm_channels_configure(struct iio_dev *indio_dev, unsigned int fl_id, struct iio_trigger *trig) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; struct stm32_dfsdm_filter_osr *flo = &fl->flo[0]; const struct iio_chan_spec *chan; unsigned int bit; int ret; fl->fast = 0; /* * In continuous mode, use fast mode configuration, * if it provides a better resolution. */ if (adc->nconv == 1 && !trig && iio_buffer_enabled(indio_dev)) { if (fl->flo[1].res >= fl->flo[0].res) { fl->fast = 1; flo = &fl->flo[1]; } } if (!flo->res) return -EINVAL; dev_dbg(&indio_dev->dev, "Samples actual resolution: %d bits", min(flo->bits, (u32)DFSDM_DATA_RES - 1)); for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { chan = indio_dev->channels + bit; ret = regmap_update_bits(regmap, DFSDM_CHCFGR2(chan->channel), DFSDM_CHCFGR2_DTRBS_MASK, DFSDM_CHCFGR2_DTRBS(flo->rshift)); if (ret) return ret; } return 0; } static int stm32_dfsdm_filter_configure(struct iio_dev *indio_dev, unsigned int fl_id, struct iio_trigger *trig) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[fl_id]; struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; u32 cr1; const struct iio_chan_spec *chan; unsigned int bit, jchg = 0; int ret; /* Average integrator oversampling */ ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_IOSR_MASK, DFSDM_FCR_IOSR(flo->iosr - 1)); if (ret) return ret; /* Filter order and Oversampling */ ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FOSR_MASK, DFSDM_FCR_FOSR(flo->fosr - 1)); if (ret) return ret; ret = regmap_update_bits(regmap, DFSDM_FCR(fl_id), DFSDM_FCR_FORD_MASK, DFSDM_FCR_FORD(fl->ford)); if (ret) return ret; ret = stm32_dfsdm_filter_set_trig(indio_dev, fl_id, trig); if (ret) return ret; ret = regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_FAST_MASK, DFSDM_CR1_FAST(fl->fast)); if (ret) return ret; /* * DFSDM modes configuration W.R.T audio/iio type modes * ---------------------------------------------------------------- * Modes | regular | regular | injected | injected | * | | continuous | | + scan | * --------------|---------|--------------|----------|------------| * single conv | x | | | | * (1 chan) | | | | | * --------------|---------|--------------|----------|------------| * 1 Audio chan | | sample freq | | | * | | or sync_mode | | | * --------------|---------|--------------|----------|------------| * 1 IIO chan | | sample freq | trigger | | * | | or sync_mode | | | * --------------|---------|--------------|----------|------------| * 2+ IIO chans | | | | trigger or | * | | | | sync_mode | * ---------------------------------------------------------------- */ if (adc->nconv == 1 && !trig) { bit = __ffs(adc->smask); chan = indio_dev->channels + bit; /* Use regular conversion for single channel without trigger */ cr1 = DFSDM_CR1_RCH(chan->channel); /* Continuous conversions triggered by SPI clk in buffer mode */ if (iio_buffer_enabled(indio_dev)) cr1 |= DFSDM_CR1_RCONT(1); cr1 |= DFSDM_CR1_RSYNC(fl->sync_mode); } else { /* Use injected conversion for multiple channels */ for_each_set_bit(bit, &adc->smask, sizeof(adc->smask) * BITS_PER_BYTE) { chan = indio_dev->channels + bit; jchg |= BIT(chan->channel); } ret = regmap_write(regmap, DFSDM_JCHGR(fl_id), jchg); if (ret < 0) return ret; /* Use scan mode for multiple channels */ cr1 = DFSDM_CR1_JSCAN((adc->nconv > 1) ? 1 : 0); /* * Continuous conversions not supported in injected mode, * either use: * - conversions in sync with filter 0 * - triggered conversions */ if (!fl->sync_mode && !trig) return -EINVAL; cr1 |= DFSDM_CR1_JSYNC(fl->sync_mode); } return regmap_update_bits(regmap, DFSDM_CR1(fl_id), DFSDM_CR1_CFG_MASK, cr1); } static int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm, struct iio_dev *indio_dev, struct iio_chan_spec *ch) { struct stm32_dfsdm_channel *df_ch; const char *of_str; int chan_idx = ch->scan_index; int ret, val; ret = of_property_read_u32_index(indio_dev->dev.of_node, "st,adc-channels", chan_idx, &ch->channel); if (ret < 0) { dev_err(&indio_dev->dev, " Error parsing 'st,adc-channels' for idx %d\n", chan_idx); return ret; } if (ch->channel >= dfsdm->num_chs) { dev_err(&indio_dev->dev, " Error bad channel number %d (max = %d)\n", ch->channel, dfsdm->num_chs); return -EINVAL; } ret = of_property_read_string_index(indio_dev->dev.of_node, "st,adc-channel-names", chan_idx, &ch->datasheet_name); if (ret < 0) { dev_err(&indio_dev->dev, " Error parsing 'st,adc-channel-names' for idx %d\n", chan_idx); return ret; } df_ch = &dfsdm->ch_list[ch->channel]; df_ch->id = ch->channel; ret = of_property_read_string_index(indio_dev->dev.of_node, "st,adc-channel-types", chan_idx, &of_str); if (!ret) { val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type); if (val < 0) return val; } else { val = 0; } df_ch->type = val; ret = of_property_read_string_index(indio_dev->dev.of_node, "st,adc-channel-clk-src", chan_idx, &of_str); if (!ret) { val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src); if (val < 0) return val; } else { val = 0; } df_ch->src = val; ret = of_property_read_u32_index(indio_dev->dev.of_node, "st,adc-alt-channel", chan_idx, &df_ch->alt_si); if (ret < 0) df_ch->alt_si = 0; return 0; } static int stm32_dfsdm_generic_channel_parse_of(struct stm32_dfsdm *dfsdm, struct iio_dev *indio_dev, struct iio_chan_spec *ch, struct fwnode_handle *node) { struct stm32_dfsdm_channel *df_ch; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct iio_backend *backend; const char *of_str; int ret, val; ret = fwnode_property_read_u32(node, "reg", &ch->channel); if (ret < 0) { dev_err(&indio_dev->dev, "Missing channel index %d\n", ret); return ret; } if (ch->channel >= dfsdm->num_chs) { dev_err(&indio_dev->dev, " Error bad channel number %d (max = %d)\n", ch->channel, dfsdm->num_chs); return -EINVAL; } ret = fwnode_property_read_string(node, "label", &ch->datasheet_name); if (ret < 0) { dev_err(&indio_dev->dev, " Error parsing 'label' for idx %d\n", ch->channel); return ret; } df_ch = &dfsdm->ch_list[ch->channel]; df_ch->id = ch->channel; ret = fwnode_property_read_string(node, "st,adc-channel-type", &of_str); if (!ret) { val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_type); if (val < 0) return val; } else { val = 0; } df_ch->type = val; ret = fwnode_property_read_string(node, "st,adc-channel-clk-src", &of_str); if (!ret) { val = stm32_dfsdm_str2val(of_str, stm32_dfsdm_chan_src); if (val < 0) return val; } else { val = 0; } df_ch->src = val; ret = fwnode_property_read_u32(node, "st,adc-alt-channel", &df_ch->alt_si); if (ret != -EINVAL) df_ch->alt_si = 0; if (adc->dev_data->type == DFSDM_IIO) { backend = devm_iio_backend_fwnode_get(&indio_dev->dev, NULL, node); if (IS_ERR(backend)) return dev_err_probe(&indio_dev->dev, PTR_ERR(backend), "Failed to get backend\n"); adc->backend[ch->scan_index] = backend; } return 0; } static ssize_t dfsdm_adc_audio_get_spiclk(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, char *buf) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); return snprintf(buf, PAGE_SIZE, "%d\n", adc->spi_freq); } static int dfsdm_adc_set_samp_freq(struct iio_dev *indio_dev, unsigned int sample_freq, unsigned int spi_freq) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); unsigned int oversamp; int ret; oversamp = DIV_ROUND_CLOSEST(spi_freq, sample_freq); if (spi_freq % sample_freq) dev_dbg(&indio_dev->dev, "Rate not accurate. requested (%u), actual (%u)\n", sample_freq, spi_freq / oversamp); ret = stm32_dfsdm_compute_all_osrs(indio_dev, oversamp); if (ret < 0) return ret; adc->sample_freq = spi_freq / oversamp; adc->oversamp = oversamp; return 0; } static ssize_t dfsdm_adc_audio_set_spiclk(struct iio_dev *indio_dev, uintptr_t priv, const struct iio_chan_spec *chan, const char *buf, size_t len) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; unsigned int sample_freq = adc->sample_freq; unsigned int spi_freq; int ret; dev_err(&indio_dev->dev, "enter %s\n", __func__); /* If DFSDM is master on SPI, SPI freq can not be updated */ if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) return -EPERM; ret = kstrtoint(buf, 0, &spi_freq); if (ret) return ret; if (!spi_freq) return -EINVAL; if (sample_freq) { ret = dfsdm_adc_set_samp_freq(indio_dev, sample_freq, spi_freq); if (ret < 0) return ret; } adc->spi_freq = spi_freq; return len; } static int stm32_dfsdm_start_conv(struct iio_dev *indio_dev, struct iio_trigger *trig) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; int ret; ret = stm32_dfsdm_channels_configure(indio_dev, adc->fl_id, trig); if (ret < 0) return ret; ret = stm32_dfsdm_start_channel(indio_dev); if (ret < 0) return ret; ret = stm32_dfsdm_filter_configure(indio_dev, adc->fl_id, trig); if (ret < 0) goto stop_channels; ret = stm32_dfsdm_start_filter(adc, adc->fl_id, trig); if (ret < 0) goto filter_unconfigure; return 0; filter_unconfigure: regmap_clear_bits(regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_CFG_MASK); stop_channels: stm32_dfsdm_stop_channel(indio_dev); return ret; } static void stm32_dfsdm_stop_conv(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id); regmap_clear_bits(regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_CFG_MASK); stm32_dfsdm_stop_channel(indio_dev); } static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev, unsigned int val) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); unsigned int watermark = DFSDM_DMA_BUFFER_SIZE / 2; unsigned int rx_buf_sz = DFSDM_DMA_BUFFER_SIZE; /* * DMA cyclic transfers are used, buffer is split into two periods. * There should be : * - always one buffer (period) DMA is working on * - one buffer (period) driver pushed to ASoC side. */ watermark = min(watermark, val * (unsigned int)(sizeof(u32))); adc->buf_sz = min(rx_buf_sz, watermark * 2 * adc->nconv); return 0; } static unsigned int stm32_dfsdm_adc_dma_residue(struct stm32_dfsdm_adc *adc) { struct dma_tx_state state; enum dma_status status; status = dmaengine_tx_status(adc->dma_chan, adc->dma_chan->cookie, &state); if (status == DMA_IN_PROGRESS) { /* Residue is size in bytes from end of buffer */ unsigned int i = adc->buf_sz - state.residue; unsigned int size; /* Return available bytes */ if (i >= adc->bufi) size = i - adc->bufi; else size = adc->buf_sz + i - adc->bufi; return size; } return 0; } static inline void stm32_dfsdm_process_data(struct stm32_dfsdm_adc *adc, s32 *buffer) { struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; unsigned int i = adc->nconv; s32 *ptr = buffer; while (i--) { /* Mask 8 LSB that contains the channel ID */ *ptr &= 0xFFFFFF00; /* Convert 2^(n-1) sample to 2^(n-1)-1 to avoid wrap-around */ if (*ptr > flo->max) *ptr -= 1; /* * Samples from filter are retrieved with 23 bits resolution * or less. Shift left to align MSB on 24 bits. */ *ptr <<= flo->lshift; ptr++; } } static void stm32_dfsdm_dma_buffer_done(void *data) { struct iio_dev *indio_dev = data; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); int available = stm32_dfsdm_adc_dma_residue(adc); size_t old_pos; /* * FIXME: In Kernel interface does not support cyclic DMA buffer,and * offers only an interface to push data samples per samples. * For this reason IIO buffer interface is not used and interface is * bypassed using a private callback registered by ASoC. * This should be a temporary solution waiting a cyclic DMA engine * support in IIO. */ dev_dbg(&indio_dev->dev, "pos = %d, available = %d\n", adc->bufi, available); old_pos = adc->bufi; while (available >= indio_dev->scan_bytes) { s32 *buffer = (s32 *)&adc->rx_buf[adc->bufi]; stm32_dfsdm_process_data(adc, buffer); available -= indio_dev->scan_bytes; adc->bufi += indio_dev->scan_bytes; if (adc->bufi >= adc->buf_sz) { if (adc->cb) adc->cb(&adc->rx_buf[old_pos], adc->buf_sz - old_pos, adc->cb_priv); adc->bufi = 0; old_pos = 0; } /* * In DMA mode the trigger services of IIO are not used * (e.g. no call to iio_trigger_poll). * Calling irq handler associated to the hardware trigger is not * relevant as the conversions have already been done. Data * transfers are performed directly in DMA callback instead. * This implementation avoids to call trigger irq handler that * may sleep, in an atomic context (DMA irq handler context). */ if (adc->dev_data->type == DFSDM_IIO) iio_push_to_buffers(indio_dev, buffer); } if (adc->cb) adc->cb(&adc->rx_buf[old_pos], adc->bufi - old_pos, adc->cb_priv); } static int stm32_dfsdm_adc_dma_start(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); /* * The DFSDM supports half-word transfers. However, for 16 bits record, * 4 bytes buswidth is kept, to avoid losing samples LSBs when left * shift is required. */ struct dma_slave_config config = { .src_addr = (dma_addr_t)adc->dfsdm->phys_base, .src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES, }; struct dma_async_tx_descriptor *desc; dma_cookie_t cookie; int ret; if (!adc->dma_chan) return -EINVAL; dev_dbg(&indio_dev->dev, "size=%d watermark=%d\n", adc->buf_sz, adc->buf_sz / 2); if (adc->nconv == 1 && !indio_dev->trig) config.src_addr += DFSDM_RDATAR(adc->fl_id); else config.src_addr += DFSDM_JDATAR(adc->fl_id); ret = dmaengine_slave_config(adc->dma_chan, &config); if (ret) return ret; /* Prepare a DMA cyclic transaction */ desc = dmaengine_prep_dma_cyclic(adc->dma_chan, adc->dma_buf, adc->buf_sz, adc->buf_sz / 2, DMA_DEV_TO_MEM, DMA_PREP_INTERRUPT); if (!desc) return -EBUSY; desc->callback = stm32_dfsdm_dma_buffer_done; desc->callback_param = indio_dev; cookie = dmaengine_submit(desc); ret = dma_submit_error(cookie); if (ret) goto err_stop_dma; /* Issue pending DMA requests */ dma_async_issue_pending(adc->dma_chan); if (adc->nconv == 1 && !indio_dev->trig) { /* Enable regular DMA transfer*/ ret = regmap_set_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_RDMAEN_MASK); } else { /* Enable injected DMA transfer*/ ret = regmap_set_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_JDMAEN_MASK); } if (ret < 0) goto err_stop_dma; return 0; err_stop_dma: dmaengine_terminate_all(adc->dma_chan); return ret; } static void stm32_dfsdm_adc_dma_stop(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); if (!adc->dma_chan) return; regmap_clear_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id), DFSDM_CR1_RDMAEN_MASK | DFSDM_CR1_JDMAEN_MASK); dmaengine_terminate_all(adc->dma_chan); } static int stm32_dfsdm_update_scan_mode(struct iio_dev *indio_dev, const unsigned long *scan_mask) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); adc->nconv = bitmap_weight(scan_mask, iio_get_masklength(indio_dev)); adc->smask = *scan_mask; dev_dbg(&indio_dev->dev, "nconv=%d mask=%lx\n", adc->nconv, *scan_mask); return 0; } static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); int i = 0; int ret; /* Reset adc buffer index */ adc->bufi = 0; if (adc->hwc) { ret = iio_hw_consumer_enable(adc->hwc); if (ret < 0) return ret; } if (adc->backend) { while (adc->backend[i]) { ret = iio_backend_enable(adc->backend[i]); if (ret < 0) return ret; i++; } } ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); if (ret < 0) goto err_stop_hwc; ret = stm32_dfsdm_adc_dma_start(indio_dev); if (ret) { dev_err(&indio_dev->dev, "Can't start DMA\n"); goto stop_dfsdm; } ret = stm32_dfsdm_start_conv(indio_dev, indio_dev->trig); if (ret) { dev_err(&indio_dev->dev, "Can't start conversion\n"); goto err_stop_dma; } return 0; err_stop_dma: stm32_dfsdm_adc_dma_stop(indio_dev); stop_dfsdm: stm32_dfsdm_stop_dfsdm(adc->dfsdm); err_stop_hwc: if (adc->hwc) iio_hw_consumer_disable(adc->hwc); return ret; } static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); int i = 0; stm32_dfsdm_stop_conv(indio_dev); stm32_dfsdm_adc_dma_stop(indio_dev); stm32_dfsdm_stop_dfsdm(adc->dfsdm); if (adc->backend) { while (adc->backend[i]) { iio_backend_disable(adc->backend[i]); i++; } } if (adc->hwc) iio_hw_consumer_disable(adc->hwc); return 0; } static const struct iio_buffer_setup_ops stm32_dfsdm_buffer_setup_ops = { .postenable = &stm32_dfsdm_postenable, .predisable = &stm32_dfsdm_predisable, }; /** * stm32_dfsdm_get_buff_cb() - register a callback that will be called when * DMA transfer period is achieved. * * @iio_dev: Handle to IIO device. * @cb: Pointer to callback function: * - data: pointer to data buffer * - size: size in byte of the data buffer * - private: pointer to consumer private structure. * @private: Pointer to consumer private structure. */ int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev, int (*cb)(const void *data, size_t size, void *private), void *private) { struct stm32_dfsdm_adc *adc; if (!iio_dev) return -EINVAL; adc = iio_priv(iio_dev); adc->cb = cb; adc->cb_priv = private; return 0; } EXPORT_SYMBOL_GPL(stm32_dfsdm_get_buff_cb); /** * stm32_dfsdm_release_buff_cb - unregister buffer callback * * @iio_dev: Handle to IIO device. */ int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev) { struct stm32_dfsdm_adc *adc; if (!iio_dev) return -EINVAL; adc = iio_priv(iio_dev); adc->cb = NULL; adc->cb_priv = NULL; return 0; } EXPORT_SYMBOL_GPL(stm32_dfsdm_release_buff_cb); static int stm32_dfsdm_single_conv(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, int *res) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); long time_left; int ret; reinit_completion(&adc->completion); adc->buffer = res; ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); if (ret < 0) return ret; ret = regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(1)); if (ret < 0) goto stop_dfsdm; adc->nconv = 1; adc->smask = BIT(chan->scan_index); ret = stm32_dfsdm_start_conv(indio_dev, NULL); if (ret < 0) { regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); goto stop_dfsdm; } time_left = wait_for_completion_interruptible_timeout(&adc->completion, DFSDM_TIMEOUT); /* Mask IRQ for regular conversion achievement*/ regmap_update_bits(adc->dfsdm->regmap, DFSDM_CR2(adc->fl_id), DFSDM_CR2_REOCIE_MASK, DFSDM_CR2_REOCIE(0)); if (time_left == 0) ret = -ETIMEDOUT; else if (time_left < 0) ret = time_left; else ret = IIO_VAL_INT; stm32_dfsdm_stop_conv(indio_dev); stm32_dfsdm_process_data(adc, res); stop_dfsdm: stm32_dfsdm_stop_dfsdm(adc->dfsdm); return ret; } static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int val, int val2, long mask) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel]; unsigned int spi_freq; int ret = -EINVAL; switch (ch->src) { case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL: spi_freq = adc->dfsdm->spi_master_freq; break; case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING: case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING: spi_freq = adc->dfsdm->spi_master_freq / 2; break; default: spi_freq = adc->spi_freq; } switch (mask) { case IIO_CHAN_INFO_OVERSAMPLING_RATIO: ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; ret = stm32_dfsdm_compute_all_osrs(indio_dev, val); if (!ret) { dev_dbg(&indio_dev->dev, "Sampling rate changed from (%u) to (%u)\n", adc->sample_freq, spi_freq / val); adc->oversamp = val; adc->sample_freq = spi_freq / val; } iio_device_release_direct_mode(indio_dev); return ret; case IIO_CHAN_INFO_SAMP_FREQ: if (!val) return -EINVAL; ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; ret = dfsdm_adc_set_samp_freq(indio_dev, val, spi_freq); iio_device_release_direct_mode(indio_dev); return ret; } return -EINVAL; } static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, struct iio_chan_spec const *chan, int *val, int *val2, long mask) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; struct stm32_dfsdm_filter_osr *flo = &fl->flo[fl->fast]; u32 max = flo->max << (flo->lshift - chan->scan_type.shift); int idx = chan->scan_index; int ret; if (flo->lshift < chan->scan_type.shift) max = flo->max >> (chan->scan_type.shift - flo->lshift); switch (mask) { case IIO_CHAN_INFO_RAW: ret = iio_device_claim_direct_mode(indio_dev); if (ret) return ret; if (adc->hwc) ret = iio_hw_consumer_enable(adc->hwc); if (adc->backend) ret = iio_backend_enable(adc->backend[idx]); if (ret < 0) { dev_err(&indio_dev->dev, "%s: IIO enable failed (channel %d)\n", __func__, chan->channel); iio_device_release_direct_mode(indio_dev); return ret; } ret = stm32_dfsdm_single_conv(indio_dev, chan, val); if (adc->hwc) iio_hw_consumer_disable(adc->hwc); if (adc->backend) iio_backend_disable(adc->backend[idx]); if (ret < 0) { dev_err(&indio_dev->dev, "%s: Conversion failed (channel %d)\n", __func__, chan->channel); iio_device_release_direct_mode(indio_dev); return ret; } iio_device_release_direct_mode(indio_dev); return IIO_VAL_INT; case IIO_CHAN_INFO_OVERSAMPLING_RATIO: *val = adc->oversamp; return IIO_VAL_INT; case IIO_CHAN_INFO_SAMP_FREQ: *val = adc->sample_freq; return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: /* * Scale is expressed in mV. * When fast mode is disabled, actual resolution may be lower * than 2^n, where n = realbits - 1. * This leads to underestimating the input voltage. * To compensate this deviation, the voltage reference can be * corrected with a factor = realbits resolution / actual max */ if (adc->backend) { ret = iio_backend_read_scale(adc->backend[idx], chan, val, NULL); if (ret < 0) return ret; *val = div_u64((u64)*val * (u64)BIT(DFSDM_DATA_RES - 1), max); *val2 = chan->scan_type.realbits; if (chan->differential) *val *= 2; } return IIO_VAL_FRACTIONAL_LOG2; case IIO_CHAN_INFO_OFFSET: /* * DFSDM output data are in the range [-2^n, 2^n], * with n = realbits - 1. * - Differential modulator: * Offset correspond to SD modulator offset. * - Single ended modulator: * Input is in [0V, Vref] range, * where 0V corresponds to -2^n, and Vref to 2^n. * Add 2^n to offset. (i.e. middle of input range) * offset = offset(sd) * vref / res(sd) * max / vref. */ if (adc->backend) { ret = iio_backend_read_offset(adc->backend[idx], chan, val, NULL); if (ret < 0) return ret; *val = div_u64((u64)max * *val, BIT(*val2 - 1)); if (!chan->differential) *val += max; } return IIO_VAL_INT; } return -EINVAL; } static int stm32_dfsdm_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig) { return stm32_dfsdm_get_jextsel(indio_dev, trig) < 0 ? -EINVAL : 0; } static const struct iio_info stm32_dfsdm_info_audio = { .hwfifo_set_watermark = stm32_dfsdm_set_watermark, .read_raw = stm32_dfsdm_read_raw, .write_raw = stm32_dfsdm_write_raw, .update_scan_mode = stm32_dfsdm_update_scan_mode, }; static const struct iio_info stm32_dfsdm_info_adc = { .hwfifo_set_watermark = stm32_dfsdm_set_watermark, .read_raw = stm32_dfsdm_read_raw, .write_raw = stm32_dfsdm_write_raw, .update_scan_mode = stm32_dfsdm_update_scan_mode, .validate_trigger = stm32_dfsdm_validate_trigger, }; static irqreturn_t stm32_dfsdm_irq(int irq, void *arg) { struct iio_dev *indio_dev = arg; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct regmap *regmap = adc->dfsdm->regmap; unsigned int status, int_en; regmap_read(regmap, DFSDM_ISR(adc->fl_id), &status); regmap_read(regmap, DFSDM_CR2(adc->fl_id), &int_en); if (status & DFSDM_ISR_REOCF_MASK) { /* Read the data register clean the IRQ status */ regmap_read(regmap, DFSDM_RDATAR(adc->fl_id), adc->buffer); complete(&adc->completion); } if (status & DFSDM_ISR_ROVRF_MASK) { if (int_en & DFSDM_CR2_ROVRIE_MASK) dev_warn(&indio_dev->dev, "Overrun detected\n"); regmap_set_bits(regmap, DFSDM_ICR(adc->fl_id), DFSDM_ICR_CLRROVRF_MASK); } return IRQ_HANDLED; } /* * Define external info for SPI Frequency and audio sampling rate that can be * configured by ASoC driver through consumer.h API */ static const struct iio_chan_spec_ext_info dfsdm_adc_audio_ext_info[] = { /* spi_clk_freq : clock freq on SPI/manchester bus used by channel */ { .name = "spi_clk_freq", .shared = IIO_SHARED_BY_TYPE, .read = dfsdm_adc_audio_get_spiclk, .write = dfsdm_adc_audio_set_spiclk, }, { } }; static void stm32_dfsdm_dma_release(struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); if (adc->dma_chan) { dma_free_coherent(adc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE, adc->rx_buf, adc->dma_buf); dma_release_channel(adc->dma_chan); } } static int stm32_dfsdm_dma_request(struct device *dev, struct iio_dev *indio_dev) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); adc->dma_chan = dma_request_chan(dev, "rx"); if (IS_ERR(adc->dma_chan)) { int ret = PTR_ERR(adc->dma_chan); adc->dma_chan = NULL; return ret; } adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE, &adc->dma_buf, GFP_KERNEL); if (!adc->rx_buf) { dma_release_channel(adc->dma_chan); return -ENOMEM; } indio_dev->modes |= INDIO_BUFFER_SOFTWARE; indio_dev->setup_ops = &stm32_dfsdm_buffer_setup_ops; return 0; } static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, struct iio_chan_spec *ch, struct fwnode_handle *child) { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); int ret; if (child) ret = stm32_dfsdm_generic_channel_parse_of(adc->dfsdm, indio_dev, ch, child); else /* Legacy binding */ ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch); if (ret < 0) return dev_err_probe(&indio_dev->dev, ret, "Failed to parse channel\n"); ch->type = IIO_VOLTAGE; ch->indexed = 1; /* * IIO_CHAN_INFO_RAW: used to compute regular conversion * IIO_CHAN_INFO_OVERSAMPLING_RATIO: used to set oversampling */ if (child) { ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE) | BIT(IIO_CHAN_INFO_OFFSET); } else { /* Legacy. Scaling not supported */ ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); } ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO) | BIT(IIO_CHAN_INFO_SAMP_FREQ); if (adc->dev_data->type == DFSDM_AUDIO) { ch->ext_info = dfsdm_adc_audio_ext_info; ch->scan_index = 0; } else { ch->scan_type.shift = 8; } ch->scan_type.sign = 's'; ch->scan_type.realbits = 24; ch->scan_type.storagebits = 32; return stm32_dfsdm_chan_configure(adc->dfsdm, &adc->dfsdm->ch_list[ch->channel]); } static int stm32_dfsdm_chan_init(struct iio_dev *indio_dev, struct iio_chan_spec *channels) { int num_ch = indio_dev->num_channels; int chan_idx = 0; int ret; for (chan_idx = 0; chan_idx < num_ch; chan_idx++) { channels[chan_idx].scan_index = chan_idx; ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &channels[chan_idx], NULL); if (ret < 0) return dev_err_probe(&indio_dev->dev, ret, "Channels init failed\n"); } return 0; } static int stm32_dfsdm_generic_chan_init(struct iio_dev *indio_dev, struct iio_chan_spec *channels) { int chan_idx = 0, ret; device_for_each_child_node_scoped(&indio_dev->dev, child) { /* Skip DAI node in DFSDM audio nodes */ if (fwnode_property_present(child, "compatible")) continue; channels[chan_idx].scan_index = chan_idx; ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &channels[chan_idx], child); if (ret < 0) return dev_err_probe(&indio_dev->dev, ret, "Channels init failed\n"); chan_idx++; } return chan_idx; } static int stm32_dfsdm_audio_init(struct device *dev, struct iio_dev *indio_dev) { struct iio_chan_spec *ch; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_channel *d_ch; bool legacy = false; int num_ch, ret; /* If st,adc-channels is defined legacy binding is used. Else assume generic binding. */ num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, "st,adc-channels"); if (num_ch == 1) legacy = true; ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL); if (!ch) return -ENOMEM; indio_dev->num_channels = 1; indio_dev->channels = ch; if (legacy) ret = stm32_dfsdm_chan_init(indio_dev, ch); else ret = stm32_dfsdm_generic_chan_init(indio_dev, ch); if (ret < 0) { dev_err(&indio_dev->dev, "Channels init failed\n"); return ret; } ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ); d_ch = &adc->dfsdm->ch_list[ch->channel]; if (d_ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) adc->spi_freq = adc->dfsdm->spi_master_freq; return stm32_dfsdm_dma_request(dev, indio_dev); } static int stm32_dfsdm_adc_init(struct device *dev, struct iio_dev *indio_dev) { struct iio_chan_spec *ch; struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); int num_ch, ret; bool legacy = false; adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING; ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp); if (ret < 0) return ret; num_ch = device_get_child_node_count(&indio_dev->dev); if (!num_ch) { /* No channels nodes found. Assume legacy binding */ num_ch = of_property_count_u32_elems(indio_dev->dev.of_node, "st,adc-channels"); if (num_ch < 0) { dev_err(&indio_dev->dev, "Bad st,adc-channels\n"); return num_ch; } legacy = true; } if (num_ch > adc->dfsdm->num_chs) { dev_err(&indio_dev->dev, "Number of channel [%d] exceeds [%d]\n", num_ch, adc->dfsdm->num_chs); return -EINVAL; } indio_dev->num_channels = num_ch; if (legacy) { /* Bind to SD modulator IIO device. */ adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev); if (IS_ERR(adc->hwc)) return dev_err_probe(&indio_dev->dev, -EPROBE_DEFER, "waiting for SD modulator\n"); } else { /* Generic binding. SD modulator IIO device not used. Use SD modulator backend. */ adc->hwc = NULL; adc->backend = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*adc->backend), GFP_KERNEL); if (!adc->backend) return -ENOMEM; } ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch), GFP_KERNEL); if (!ch) return -ENOMEM; indio_dev->channels = ch; if (legacy) ret = stm32_dfsdm_chan_init(indio_dev, ch); else ret = stm32_dfsdm_generic_chan_init(indio_dev, ch); if (ret < 0) return ret; init_completion(&adc->completion); /* Optionally request DMA */ ret = stm32_dfsdm_dma_request(dev, indio_dev); if (ret) { if (ret != -ENODEV) return dev_err_probe(dev, ret, "DMA channel request failed with\n"); dev_dbg(dev, "No DMA support\n"); return 0; } ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, NULL, &stm32_dfsdm_buffer_setup_ops); if (ret) { stm32_dfsdm_dma_release(indio_dev); dev_err(&indio_dev->dev, "buffer setup failed\n"); return ret; } /* lptimer/timer hardware triggers */ indio_dev->modes |= INDIO_HARDWARE_TRIGGERED; return 0; } static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_adc_data = { .type = DFSDM_IIO, .init = stm32_dfsdm_adc_init, }; static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_audio_data = { .type = DFSDM_AUDIO, .init = stm32_dfsdm_audio_init, }; static const struct of_device_id stm32_dfsdm_adc_match[] = { { .compatible = "st,stm32-dfsdm-adc", .data = &stm32h7_dfsdm_adc_data, }, { .compatible = "st,stm32-dfsdm-dmic", .data = &stm32h7_dfsdm_audio_data, }, {} }; MODULE_DEVICE_TABLE(of, stm32_dfsdm_adc_match); static int stm32_dfsdm_adc_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct stm32_dfsdm_adc *adc; struct device_node *np = dev->of_node; const struct stm32_dfsdm_dev_data *dev_data; struct iio_dev *iio; char *name; int ret, irq, val; dev_data = of_device_get_match_data(dev); iio = devm_iio_device_alloc(dev, sizeof(*adc)); if (!iio) { dev_err(dev, "%s: Failed to allocate IIO\n", __func__); return -ENOMEM; } adc = iio_priv(iio); adc->dfsdm = dev_get_drvdata(dev->parent); iio->dev.of_node = np; iio->modes = INDIO_DIRECT_MODE; platform_set_drvdata(pdev, iio); ret = of_property_read_u32(dev->of_node, "reg", &adc->fl_id); if (ret != 0 || adc->fl_id >= adc->dfsdm->num_fls) { dev_err(dev, "Missing or bad reg property\n"); return -EINVAL; } name = devm_kzalloc(dev, sizeof("dfsdm-adc0"), GFP_KERNEL); if (!name) return -ENOMEM; if (dev_data->type == DFSDM_AUDIO) { iio->info = &stm32_dfsdm_info_audio; snprintf(name, sizeof("dfsdm-pdm0"), "dfsdm-pdm%d", adc->fl_id); } else { iio->info = &stm32_dfsdm_info_adc; snprintf(name, sizeof("dfsdm-adc0"), "dfsdm-adc%d", adc->fl_id); } iio->name = name; /* * In a first step IRQs generated for channels are not treated. * So IRQ associated to filter instance 0 is dedicated to the Filter 0. */ irq = platform_get_irq(pdev, 0); if (irq < 0) return irq; ret = devm_request_irq(dev, irq, stm32_dfsdm_irq, 0, pdev->name, iio); if (ret < 0) { dev_err(dev, "Failed to request IRQ\n"); return ret; } ret = of_property_read_u32(dev->of_node, "st,filter-order", &val); if (ret < 0) { dev_err(dev, "Failed to set filter order\n"); return ret; } adc->dfsdm->fl_list[adc->fl_id].ford = val; ret = of_property_read_u32(dev->of_node, "st,filter0-sync", &val); if (!ret) adc->dfsdm->fl_list[adc->fl_id].sync_mode = val; adc->dev_data = dev_data; ret = dev_data->init(dev, iio); if (ret < 0) return ret; ret = iio_device_register(iio); if (ret < 0) goto err_cleanup; if (dev_data->type == DFSDM_AUDIO) { ret = of_platform_populate(np, NULL, NULL, dev); if (ret < 0) { dev_err(dev, "Failed to find an audio DAI\n"); goto err_unregister; } } return 0; err_unregister: iio_device_unregister(iio); err_cleanup: stm32_dfsdm_dma_release(iio); return ret; } static void stm32_dfsdm_adc_remove(struct platform_device *pdev) { struct iio_dev *indio_dev = platform_get_drvdata(pdev); struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); if (adc->dev_data->type == DFSDM_AUDIO) of_platform_depopulate(&pdev->dev); iio_device_unregister(indio_dev); stm32_dfsdm_dma_release(indio_dev); } static int stm32_dfsdm_adc_suspend(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); if (iio_buffer_enabled(indio_dev)) stm32_dfsdm_predisable(indio_dev); return 0; } static int stm32_dfsdm_adc_resume(struct device *dev) { struct iio_dev *indio_dev = dev_get_drvdata(dev); struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); const struct iio_chan_spec *chan; struct stm32_dfsdm_channel *ch; int i, ret; /* restore channels configuration */ for (i = 0; i < indio_dev->num_channels; i++) { chan = indio_dev->channels + i; ch = &adc->dfsdm->ch_list[chan->channel]; ret = stm32_dfsdm_chan_configure(adc->dfsdm, ch); if (ret) return ret; } if (iio_buffer_enabled(indio_dev)) stm32_dfsdm_postenable(indio_dev); return 0; } static DEFINE_SIMPLE_DEV_PM_OPS(stm32_dfsdm_adc_pm_ops, stm32_dfsdm_adc_suspend, stm32_dfsdm_adc_resume); static struct platform_driver stm32_dfsdm_adc_driver = { .driver = { .name = "stm32-dfsdm-adc", .of_match_table = stm32_dfsdm_adc_match, .pm = pm_sleep_ptr(&stm32_dfsdm_adc_pm_ops), }, .probe = stm32_dfsdm_adc_probe, .remove = stm32_dfsdm_adc_remove, }; module_platform_driver(stm32_dfsdm_adc_driver); MODULE_DESCRIPTION("STM32 sigma delta ADC"); MODULE_AUTHOR("Arnaud Pouliquen "); MODULE_LICENSE("GPL v2"); MODULE_IMPORT_NS("IIO_BACKEND");