ASR_BASE
Change-Id: Icf3719cc0afe3eeb3edc7fa80a2eb5199ca9dda1
diff --git a/marvell/linux/drivers/iio/adc/stm32-dfsdm-adc.c b/marvell/linux/drivers/iio/adc/stm32-dfsdm-adc.c
new file mode 100644
index 0000000..0c92eb3
--- /dev/null
+++ b/marvell/linux/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -0,0 +1,1710 @@
+// 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 <arnaud.pouliquen@st.com>.
+ */
+
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+#include <linux/iio/adc/stm32-dfsdm-adc.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/hw-consumer.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/timer/stm32-lptim-trigger.h>
+#include <linux/iio/timer/stm32-timer-trigger.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/slab.h>
+
+#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 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("%s: Requested oversampling: %d\n", __func__, 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;
+
+ pr_debug("%s: fast %d, fosr %d, iosr %d, res 0x%llx/%d bits, rshift %d, lshift %d\n",
+ __func__, 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 stm32_dfsdm_adc *adc)
+{
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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 stm32_dfsdm_adc *adc)
+{
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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 stm32_dfsdm_adc *adc,
+ unsigned int fl_id,
+ struct iio_trigger *trig)
+{
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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 stm32_dfsdm_adc *adc,
+ unsigned int fl_id,
+ struct iio_trigger *trig)
+{
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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 &&
+ (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE)) {
+ if (fl->flo[1].res >= fl->flo[0].res) {
+ fl->fast = 1;
+ flo = &fl->flo[1];
+ }
+ }
+
+ if (!flo->res)
+ return -EINVAL;
+
+ 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 stm32_dfsdm_adc *adc,
+ unsigned int fl_id,
+ struct iio_trigger *trig)
+{
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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(adc, 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 (indio_dev->currentmode & INDIO_BUFFER_SOFTWARE)
+ 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 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 stm32_dfsdm_adc *adc,
+ struct iio_trigger *trig)
+{
+ struct regmap *regmap = adc->dfsdm->regmap;
+ int ret;
+
+ ret = stm32_dfsdm_channels_configure(adc, adc->fl_id, trig);
+ if (ret < 0)
+ return ret;
+
+ ret = stm32_dfsdm_start_channel(adc);
+ if (ret < 0)
+ return ret;
+
+ ret = stm32_dfsdm_filter_configure(adc, 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_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+ DFSDM_CR1_CFG_MASK, 0);
+stop_channels:
+ stm32_dfsdm_stop_channel(adc);
+
+ return ret;
+}
+
+static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc)
+{
+ struct regmap *regmap = adc->dfsdm->regmap;
+
+ stm32_dfsdm_stop_filter(adc->dfsdm, adc->fl_id);
+
+ regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id),
+ DFSDM_CR1_CFG_MASK, 0);
+
+ stm32_dfsdm_stop_channel(adc);
+}
+
+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, "%s: pos = %d, available = %d\n", __func__,
+ 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, "%s size=%d watermark=%d\n", __func__,
+ 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_update_bits(adc->dfsdm->regmap,
+ DFSDM_CR1(adc->fl_id),
+ DFSDM_CR1_RDMAEN_MASK,
+ DFSDM_CR1_RDMAEN_MASK);
+ } else {
+ /* Enable injected DMA transfer*/
+ ret = regmap_update_bits(adc->dfsdm->regmap,
+ DFSDM_CR1(adc->fl_id),
+ DFSDM_CR1_JDMAEN_MASK,
+ 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_update_bits(adc->dfsdm->regmap, DFSDM_CR1(adc->fl_id),
+ DFSDM_CR1_RDMAEN_MASK | DFSDM_CR1_JDMAEN_MASK, 0);
+ 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, indio_dev->masklength);
+ 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 ret;
+
+ /* Reset adc buffer index */
+ adc->bufi = 0;
+
+ if (adc->hwc) {
+ ret = iio_hw_consumer_enable(adc->hwc);
+ if (ret < 0)
+ return ret;
+ }
+
+ 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(adc, 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_postenable(struct iio_dev *indio_dev)
+{
+ int ret;
+
+ if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED) {
+ ret = iio_triggered_buffer_postenable(indio_dev);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = __stm32_dfsdm_postenable(indio_dev);
+ if (ret < 0)
+ goto err_predisable;
+
+ return 0;
+
+err_predisable:
+ if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
+ iio_triggered_buffer_predisable(indio_dev);
+
+ return ret;
+}
+
+static void __stm32_dfsdm_predisable(struct iio_dev *indio_dev)
+{
+ struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+
+ stm32_dfsdm_stop_conv(adc);
+
+ stm32_dfsdm_adc_dma_stop(indio_dev);
+
+ stm32_dfsdm_stop_dfsdm(adc->dfsdm);
+
+ if (adc->hwc)
+ iio_hw_consumer_disable(adc->hwc);
+}
+
+static int stm32_dfsdm_predisable(struct iio_dev *indio_dev)
+{
+ __stm32_dfsdm_predisable(indio_dev);
+
+ if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
+ iio_triggered_buffer_predisable(indio_dev);
+
+ 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 timeout;
+ 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(adc, 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;
+ }
+
+ timeout = 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 (timeout == 0)
+ ret = -ETIMEDOUT;
+ else if (timeout < 0)
+ ret = timeout;
+ else
+ ret = IIO_VAL_INT;
+
+ stm32_dfsdm_stop_conv(adc);
+
+ 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 (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)
+ adc->oversamp = 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;
+
+ 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;
+ }
+
+ 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);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
+ ret = iio_hw_consumer_enable(adc->hwc);
+ 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);
+ iio_hw_consumer_disable(adc->hwc);
+ 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;
+ }
+
+ 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 stm32_dfsdm_adc *adc = arg;
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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_update_bits(regmap, DFSDM_ICR(adc->fl_id),
+ DFSDM_ICR_CLRROVRF_MASK,
+ 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 stm32_dfsdm_adc *adc = iio_priv(indio_dev);
+ int ret;
+
+ ret = stm32_dfsdm_channel_parse_of(adc->dfsdm, indio_dev, ch);
+ if (ret < 0)
+ return ret;
+
+ 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
+ */
+ 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;
+ } 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_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;
+ int ret;
+
+ ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL);
+ if (!ch)
+ return -ENOMEM;
+
+ ch->scan_index = 0;
+
+ ret = stm32_dfsdm_adc_chan_init_one(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;
+
+ indio_dev->num_channels = 1;
+ indio_dev->channels = ch;
+
+ 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;
+ int ret, chan_idx;
+
+ adc->oversamp = DFSDM_DEFAULT_OVERSAMPLING;
+ ret = stm32_dfsdm_compute_all_osrs(indio_dev, adc->oversamp);
+ if (ret < 0)
+ return ret;
+
+ num_ch = of_property_count_u32_elems(indio_dev->dev.of_node,
+ "st,adc-channels");
+ if (num_ch < 0 || num_ch > adc->dfsdm->num_chs) {
+ dev_err(&indio_dev->dev, "Bad st,adc-channels\n");
+ return num_ch < 0 ? num_ch : -EINVAL;
+ }
+
+ /* Bind to SD modulator IIO device */
+ adc->hwc = devm_iio_hw_consumer_alloc(&indio_dev->dev);
+ if (IS_ERR(adc->hwc))
+ return -EPROBE_DEFER;
+
+ ch = devm_kcalloc(&indio_dev->dev, num_ch, sizeof(*ch),
+ GFP_KERNEL);
+ if (!ch)
+ return -ENOMEM;
+
+ for (chan_idx = 0; chan_idx < num_ch; chan_idx++) {
+ ch[chan_idx].scan_index = chan_idx;
+ ret = stm32_dfsdm_adc_chan_init_one(indio_dev, &ch[chan_idx]);
+ if (ret < 0) {
+ dev_err(&indio_dev->dev, "Channels init failed\n");
+ return ret;
+ }
+ }
+
+ indio_dev->num_channels = num_ch;
+ indio_dev->channels = ch;
+
+ init_completion(&adc->completion);
+
+ /* Optionally request DMA */
+ ret = stm32_dfsdm_dma_request(dev, indio_dev);
+ if (ret) {
+ if (ret != -ENODEV) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev,
+ "DMA channel request failed with %d\n",
+ ret);
+ return ret;
+ }
+
+ 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.parent = dev;
+ iio->dev.of_node = np;
+ iio->modes = INDIO_DIRECT_MODE;
+
+ platform_set_drvdata(pdev, adc);
+
+ 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, adc);
+ 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 int stm32_dfsdm_adc_remove(struct platform_device *pdev)
+{
+ struct stm32_dfsdm_adc *adc = platform_get_drvdata(pdev);
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+
+ if (adc->dev_data->type == DFSDM_AUDIO)
+ of_platform_depopulate(&pdev->dev);
+ iio_device_unregister(indio_dev);
+ stm32_dfsdm_dma_release(indio_dev);
+
+ return 0;
+}
+
+static int __maybe_unused stm32_dfsdm_adc_suspend(struct device *dev)
+{
+ struct stm32_dfsdm_adc *adc = dev_get_drvdata(dev);
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+
+ if (iio_buffer_enabled(indio_dev))
+ __stm32_dfsdm_predisable(indio_dev);
+
+ return 0;
+}
+
+static int __maybe_unused stm32_dfsdm_adc_resume(struct device *dev)
+{
+ struct stm32_dfsdm_adc *adc = dev_get_drvdata(dev);
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+ 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 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 = &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 <arnaud.pouliquen@st.com>");
+MODULE_LICENSE("GPL v2");