Please find my comments in-line Thanks and Regards, Arnaud On 03/19/2017 11:38 PM, Jonathan Cameron wrote: > On 17/03/17 14:08, Arnaud Pouliquen wrote: >> Add DFSDM driver to handle PDM audio microphones. >> >> Signed-off-by: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx> > So key element here is that we really need to have a proper way of > doing DMA buffer consumers from IIO (as you said in your cover letter). > > Not entirely obvious how to do this. Would like some input from Lars > if possible. I'm afraid I don't have an suitable hardware to try anything > out on (or the time really!). This will obviously be quite different from > the single scan stuff you have seen is there at the moment. I saw 2 other drivers ti_am335x_adc.c and stm32_adc.c) that use cyclic DMA. I suppose that problematics are similar. Perhaps the extra constrains in DFSDM is the in-kernel API used to get the data. > > Whether this whole approach makes sense vs doing the dma in the alsa driver > isn't clear to me. > > On the plus side, presumably we'll get love dma ADC support for free > as part of doing it this way ;) > > It's been a while since I looked at the IIO dma buffer stuff at all. Will > try and refresh my memory sometime this week. Ok, i will wait your feedback (and Lars's one) before updating my code for next version. > > Jonathan >> --- >> drivers/iio/adc/Kconfig | 13 + >> drivers/iio/adc/Makefile | 1 + >> drivers/iio/adc/stm32-dfsdm-audio.c | 720 ++++++++++++++++++++++++++++++ >> include/linux/iio/adc/stm32-dfsdm-audio.h | 41 ++ >> 4 files changed, 775 insertions(+) >> create mode 100644 drivers/iio/adc/stm32-dfsdm-audio.c >> create mode 100644 include/linux/iio/adc/stm32-dfsdm-audio.h >> >> diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig >> index 3e0eb11..c108933 100644 >> --- a/drivers/iio/adc/Kconfig >> +++ b/drivers/iio/adc/Kconfig >> @@ -478,6 +478,19 @@ config STM32_DFSDM_ADC >> This driver can also be built as a module. If so, the module >> will be called stm32-dfsdm-adc. >> >> +config STM32_DFSDM_AUDIO >> + tristate "STMicroelectronics STM32 dfsdm audio >> + depends on (ARCH_STM32 && OF) || COMPILE_TEST >> + select STM32_DFSDM_CORE >> + select REGMAP_MMIO >> + select IIO_BUFFER_DMAENGINE >> + help >> + Select this option to support Audio PDM micophone for >> + STMicroelectronics STM32 digital filter for sigma delta converter. >> + >> + This driver can also be built as a module. If so, the module >> + will be called stm32-dfsdm-audio. >> + >> config STX104 >> tristate "Apex Embedded Systems STX104 driver" >> depends on X86 && ISA_BUS_API >> diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile >> index 161f271..79f975d 100644 >> --- a/drivers/iio/adc/Makefile >> +++ b/drivers/iio/adc/Makefile >> @@ -44,6 +44,7 @@ obj-$(CONFIG_STX104) += stx104.o >> obj-$(CONFIG_STM32_ADC_CORE) += stm32-adc-core.o >> obj-$(CONFIG_STM32_ADC) += stm32-adc.o >> obj-$(CONFIG_STM32_DFSDM_ADC) += stm32-dfsdm-adc.o >> +obj-$(CONFIG_STM32_DFSDM_AUDIO) += stm32-dfsdm-audio.o >> obj-$(CONFIG_STM32_DFSDM_CORE) += stm32-dfsdm-core.o >> obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o >> obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o >> diff --git a/drivers/iio/adc/stm32-dfsdm-audio.c b/drivers/iio/adc/stm32-dfsdm-audio.c >> new file mode 100644 >> index 0000000..115ef8f >> --- /dev/null >> +++ b/drivers/iio/adc/stm32-dfsdm-audio.c >> @@ -0,0 +1,720 @@ >> +/* >> + * This file is the ADC part of of the STM32 DFSDM driver >> + * >> + * Copyright (C) 2017, STMicroelectronics - All Rights Reserved >> + * Author: Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>. >> + * >> + * License type: GPLv2 >> + * >> + * This program is free software; you can redistribute it and/or modify it >> + * under the terms of the GNU General Public License version 2 as published by >> + * the Free Software Foundation. >> + * >> + * 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 <http://www.gnu.org/licenses/>. >> + */ >> + >> +#include <linux/dmaengine.h> >> +#include <linux/dma-mapping.h> >> +#include <linux/interrupt.h> >> +#include <linux/module.h> >> +#include <linux/of.h> >> +#include <linux/platform_device.h> >> +#include <linux/regmap.h> >> +#include <linux/slab.h> >> + >> +#include <linux/iio/buffer.h> >> +#include <linux/iio/hw_consumer.h> >> +#include <linux/iio/sysfs.h> >> +#include <linux/iio/trigger.h> >> +#include <linux/iio/trigger_consumer.h> >> +#include <linux/iio/triggered_buffer.h> >> + >> +#include "stm32-dfsdm.h" >> + >> +#define DFSDM_DMA_BUFFER_SIZE (4 * PAGE_SIZE) >> + >> +struct stm32_dfsdm_audio { >> + struct stm32_dfsdm *dfsdm; >> + unsigned int fl_id; >> + unsigned int ch_id; >> + unsigned int spi_freq; /* SPI bus clock frequency */ >> + unsigned int sample_freq; /* Sample frequency after filter decimation */ >> + >> + 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; >> + >> + int (*cb)(const void *data, size_t size, void *cb_priv); >> + void *cb_priv; >> +}; >> + >> +const char *stm32_dfsdm_spi_trigger = DFSDM_SPI_TRIGGER_NAME; >> + >> +static ssize_t dfsdm_audio_get_rate(struct iio_dev *indio_dev, uintptr_t priv, >> + const struct iio_chan_spec *chan, char *buf) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + >> + return snprintf(buf, PAGE_SIZE, "%d\n", pdmc->sample_freq); >> +} >> + >> +static ssize_t dfsdm_audio_set_rate(struct iio_dev *indio_dev, uintptr_t priv, >> + const struct iio_chan_spec *chan, >> + const char *buf, size_t len) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + struct stm32_dfsdm_filter *fl = &pdmc->dfsdm->fl_list[pdmc->fl_id]; >> + struct stm32_dfsdm_channel *ch = &pdmc->dfsdm->ch_list[pdmc->ch_id]; >> + unsigned int spi_freq = pdmc->spi_freq; >> + unsigned int sample_freq; >> + int ret; >> + >> + ret = kstrtoint(buf, 0, &sample_freq); >> + if (ret) >> + return ret; >> + >> + dev_dbg(&indio_dev->dev, "Requested sample_freq :%d\n", sample_freq); >> + if (!sample_freq) >> + return -EINVAL; >> + >> + if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) >> + spi_freq = pdmc->dfsdm->spi_master_freq; >> + >> + if (spi_freq % sample_freq) >> + dev_warn(&indio_dev->dev, "Sampling rate not accurate (%d)\n", >> + spi_freq / (spi_freq / sample_freq)); >> + >> + ret = stm32_dfsdm_set_osrs(fl, 0, (spi_freq / sample_freq)); >> + if (ret < 0) { >> + dev_err(&indio_dev->dev, >> + "Not able to find filter parameter that match!\n"); >> + return ret; >> + } >> + pdmc->sample_freq = sample_freq; >> + >> + return len; >> +} >> + >> +static ssize_t dfsdm_audio_get_spiclk(struct iio_dev *indio_dev, uintptr_t priv, >> + const struct iio_chan_spec *chan, >> + char *buf) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + >> + return snprintf(buf, PAGE_SIZE, "%d\n", pdmc->spi_freq); >> +} >> + >> +static ssize_t dfsdm_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_audio *pdmc = iio_priv(indio_dev); >> + struct stm32_dfsdm_filter *fl = &pdmc->dfsdm->fl_list[pdmc->fl_id]; >> + struct stm32_dfsdm_channel *ch = &pdmc->dfsdm->ch_list[pdmc->ch_id]; >> + unsigned int sample_freq = pdmc->sample_freq; >> + unsigned int spi_freq; >> + int ret; >> + >> + /* 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; >> + >> + dev_dbg(&indio_dev->dev, "Requested frequency :%d\n", spi_freq); >> + if (!spi_freq) >> + return -EINVAL; >> + >> + if (sample_freq) { >> + if (spi_freq % sample_freq) >> + dev_warn(&indio_dev->dev, >> + "Sampling rate not accurate (%d)\n", >> + spi_freq / (spi_freq / sample_freq)); >> + >> + ret = stm32_dfsdm_set_osrs(fl, 0, (spi_freq / sample_freq)); >> + if (ret < 0) { >> + dev_err(&indio_dev->dev, >> + "No filter parameters that match!\n"); >> + return ret; >> + } >> + } >> + pdmc->spi_freq = spi_freq; >> + >> + return len; >> +} >> + >> +/* >> + * 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_ext_info[] = { >> + /* filter oversampling: Post filter oversampling ratio */ >> + { >> + .name = "audio_sampling_rate", >> + .shared = IIO_SHARED_BY_TYPE, >> + .read = dfsdm_audio_get_rate, >> + .write = dfsdm_audio_set_rate, >> + }, >> + /* data_right_bit_shift : Filter output data shifting */ >> + { >> + .name = "spi_clk_freq", >> + .shared = IIO_SHARED_BY_TYPE, >> + .read = dfsdm_audio_get_spiclk, >> + .write = dfsdm_audio_set_spiclk, >> + }, >> + {}, >> +}; >> + >> +static int stm32_dfsdm_start_conv(struct stm32_dfsdm_audio *pdmc, bool single) >> +{ >> + struct regmap *regmap = pdmc->dfsdm->regmap; >> + int ret; >> + >> + ret = stm32_dfsdm_start_dfsdm(pdmc->dfsdm); >> + if (ret < 0) >> + return ret; >> + >> + ret = stm32_dfsdm_start_channel(pdmc->dfsdm, pdmc->ch_id); >> + if (ret < 0) >> + goto stop_dfsdm; >> + >> + ret = stm32_dfsdm_filter_configure(pdmc->dfsdm, pdmc->fl_id, >> + pdmc->ch_id); >> + if (ret < 0) >> + goto stop_channels; >> + >> + /* Enable DMA transfer*/ >> + ret = regmap_update_bits(regmap, DFSDM_CR1(pdmc->fl_id), >> + DFSDM_CR1_RDMAEN_MASK, DFSDM_CR1_RDMAEN(1)); >> + if (ret < 0) >> + return ret; >> + >> + /* Enable conversion triggered by SPI clock*/ >> + ret = regmap_update_bits(regmap, DFSDM_CR1(pdmc->fl_id), >> + DFSDM_CR1_RCONT_MASK, DFSDM_CR1_RCONT(1)); >> + if (ret < 0) >> + return ret; >> + >> + ret = stm32_dfsdm_start_filter(pdmc->dfsdm, pdmc->fl_id); >> + if (ret < 0) >> + goto stop_channels; >> + >> + return 0; >> + >> +stop_channels: >> + stm32_dfsdm_stop_channel(pdmc->dfsdm, pdmc->fl_id); >> +stop_dfsdm: >> + stm32_dfsdm_stop_dfsdm(pdmc->dfsdm); >> + >> + return ret; >> +} >> + >> +static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_audio *pdmc) >> +{ >> + stm32_dfsdm_stop_filter(pdmc->dfsdm, pdmc->fl_id); >> + >> + stm32_dfsdm_stop_channel(pdmc->dfsdm, pdmc->ch_id); >> + >> + stm32_dfsdm_stop_dfsdm(pdmc->dfsdm); >> +} >> + >> +static int stm32_dfsdm_set_watermark(struct iio_dev *indio_dev, >> + unsigned int val) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + unsigned int watermark = DFSDM_DMA_BUFFER_SIZE / 2; >> + >> + /* >> + * 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))); >> + pdmc->buf_sz = watermark * 2; >> + >> + return 0; >> +} >> + >> +int stm32_dfsdm_validate_trigger(struct iio_dev *indio_dev, >> + struct iio_trigger *trig) >> +{ >> + if (!strcmp(stm32_dfsdm_spi_trigger, trig->name)) >> + return 0; >> + >> + return -EINVAL; >> +} >> + >> +static const struct iio_info stm32_dfsdm_info_pdmc = { >> + .hwfifo_set_watermark = stm32_dfsdm_set_watermark, >> + .driver_module = THIS_MODULE, >> + .validate_trigger = stm32_dfsdm_validate_trigger, >> +}; >> + >> +static irqreturn_t stm32_dfsdm_irq(int irq, void *arg) >> +{ >> + struct stm32_dfsdm_audio *pdmc = arg; >> + struct iio_dev *indio_dev = iio_priv_to_dev(pdmc); >> + struct regmap *regmap = pdmc->dfsdm->regmap; >> + unsigned int status; >> + >> + regmap_read(regmap, DFSDM_ISR(pdmc->fl_id), &status); >> + >> + if (status & DFSDM_ISR_ROVRF_MASK) { >> + dev_err(&indio_dev->dev, "Unexpected Conversion overflow\n"); >> + regmap_update_bits(regmap, DFSDM_ICR(pdmc->fl_id), >> + DFSDM_ICR_CLRROVRF_MASK, >> + DFSDM_ICR_CLRROVRF_MASK); >> + } >> + >> + return IRQ_HANDLED; >> +} >> + >> +static unsigned int stm32_dfsdm_audio_avail_data(struct stm32_dfsdm_audio *pdmc) >> +{ >> + struct dma_tx_state state; >> + enum dma_status status; >> + >> + status = dmaengine_tx_status(pdmc->dma_chan, >> + pdmc->dma_chan->cookie, >> + &state); >> + if (status == DMA_IN_PROGRESS) { >> + /* Residue is size in bytes from end of buffer */ >> + unsigned int i = pdmc->buf_sz - state.residue; >> + unsigned int size; >> + >> + /* Return available bytes */ >> + if (i >= pdmc->bufi) >> + size = i - pdmc->bufi; >> + else >> + size = pdmc->buf_sz + i - pdmc->bufi; >> + >> + return size; >> + } >> + >> + return 0; >> +} >> + >> +static void stm32_dfsdm_audio_dma_buffer_done(void *data) >> +{ >> + struct iio_dev *indio_dev = data; >> + >> + iio_trigger_poll_chained(indio_dev->trig); > This shouldn't be going through the trigger infrastructure at all really. > I'm not 100% sure what doing so is gaining you... Yes i will clean trigger part and call directly the ASoC callback here. >> +} >> + >> +static int stm32_dfsdm_audio_dma_start(struct iio_dev *indio_dev) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + struct dma_async_tx_descriptor *desc; >> + dma_cookie_t cookie; >> + int ret; >> + >> + if (!pdmc->dma_chan) >> + return -EINVAL; >> + >> + dev_dbg(&indio_dev->dev, "%s size=%d watermark=%d\n", __func__, >> + pdmc->buf_sz, pdmc->buf_sz / 2); >> + >> + /* Prepare a DMA cyclic transaction */ >> + desc = dmaengine_prep_dma_cyclic(pdmc->dma_chan, >> + pdmc->dma_buf, >> + pdmc->buf_sz, pdmc->buf_sz / 2, >> + DMA_DEV_TO_MEM, >> + DMA_PREP_INTERRUPT); >> + if (!desc) >> + return -EBUSY; >> + >> + desc->callback = stm32_dfsdm_audio_dma_buffer_done; >> + desc->callback_param = indio_dev; >> + >> + cookie = dmaengine_submit(desc); >> + ret = dma_submit_error(cookie); >> + if (ret) { >> + dmaengine_terminate_all(pdmc->dma_chan); >> + return ret; >> + } >> + >> + /* Issue pending DMA requests */ >> + dma_async_issue_pending(pdmc->dma_chan); >> + >> + return 0; >> +} >> + >> +static int stm32_dfsdm_postenable(struct iio_dev *indio_dev) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + int ret; >> + >> + dev_dbg(&indio_dev->dev, "%s\n", __func__); >> + /* Reset pdmc buffer index */ >> + pdmc->bufi = 0; >> + >> + ret = stm32_dfsdm_start_conv(pdmc, false); >> + if (ret) { >> + dev_err(&indio_dev->dev, "Can't start conversion\n"); >> + return ret; >> + } >> + >> + ret = stm32_dfsdm_audio_dma_start(indio_dev); >> + if (ret) { >> + dev_err(&indio_dev->dev, "Can't start DMA\n"); >> + goto err_stop_conv; >> + } >> + >> + ret = iio_triggered_buffer_postenable(indio_dev); >> + if (ret < 0) { >> + dev_err(&indio_dev->dev, "%s :%d\n", __func__, __LINE__); >> + goto err_stop_dma; >> + } >> + >> + return 0; >> + >> +err_stop_dma: >> + if (pdmc->dma_chan) >> + dmaengine_terminate_all(pdmc->dma_chan); >> +err_stop_conv: >> + stm32_dfsdm_stop_conv(pdmc); >> + >> + return ret; >> +} >> + >> +static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + int ret; >> + >> + dev_dbg(&indio_dev->dev, "%s\n", __func__); >> + ret = iio_triggered_buffer_predisable(indio_dev); >> + if (ret < 0) >> + dev_err(&indio_dev->dev, "Predisable failed\n"); >> + >> + if (pdmc->dma_chan) >> + dmaengine_terminate_all(pdmc->dma_chan); >> + >> + stm32_dfsdm_stop_conv(pdmc); >> + >> + return 0; >> +} >> + >> +static const struct iio_buffer_setup_ops stm32_dfsdm_buffer_setup_ops = { >> + .postenable = &stm32_dfsdm_postenable, >> + .predisable = &stm32_dfsdm_predisable, >> +}; >> + >> +static irqreturn_t stm32_dfsdm_audio_trigger_handler(int irq, void *p) >> +{ > OK. So now I kind of understand what the trigger provided in the adc driver > was about. hmm. Triggers are supposed to be per sample so this is indeed > a hack. We need fullblown DMA buffer consumers to do this right. Yes exactly. > > Probably best person to comment on that is Lars. >> + struct iio_poll_func *pf = p; >> + struct iio_dev *indio_dev = pf->indio_dev; >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + size_t old_pos; >> + int available = stm32_dfsdm_audio_avail_data(pdmc); >> + >> + /* >> + * Buffer interface is not support cyclic DMA buffer,and offer only >> + * an interface to push data samples per samples. >> + * For this reason iio_push_to_buffers_with_timestamp in not used >> + * and interface is hacked 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__, >> + pdmc->bufi, available); >> + old_pos = pdmc->bufi; >> + while (available >= indio_dev->scan_bytes) { >> + u32 *buffer = (u32 *)&pdmc->rx_buf[pdmc->bufi]; >> + >> + /* Mask 8 LSB that contains the channel ID */ >> + *buffer &= 0xFFFFFF00; >> + available -= indio_dev->scan_bytes; >> + pdmc->bufi += indio_dev->scan_bytes; >> + if (pdmc->bufi >= pdmc->buf_sz) { >> + if (pdmc->cb) >> + pdmc->cb(&pdmc->rx_buf[old_pos], >> + pdmc->buf_sz - old_pos, pdmc->cb_priv); >> + pdmc->bufi = 0; >> + old_pos = 0; >> + } >> + } >> + if (pdmc->cb) >> + pdmc->cb(&pdmc->rx_buf[old_pos], pdmc->bufi - old_pos, >> + pdmc->cb_priv); >> + >> + iio_trigger_notify_done(indio_dev->trig); >> + >> + return IRQ_HANDLED; >> +} >> + >> +/** >> + * 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_audio *pdmc; >> + >> + if (!iio_dev) >> + return -EINVAL; >> + pdmc = iio_priv(iio_dev); >> + >> + if (iio_dev != iio_priv_to_dev(pdmc)) >> + return -EINVAL; >> + >> + pdmc->cb = cb; >> + pdmc->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_audio *pdmc; >> + >> + if (!iio_dev) >> + return -EINVAL; >> + pdmc = iio_priv(iio_dev); >> + >> + if (iio_dev != iio_priv_to_dev(pdmc)) >> + return -EINVAL; >> + pdmc->cb = NULL; >> + pdmc->cb_priv = NULL; >> + >> + return 0; >> +} >> +EXPORT_SYMBOL_GPL(stm32_dfsdm_release_buff_cb); >> + >> +static int stm32_dfsdm_audio_chan_init(struct iio_dev *indio_dev) >> +{ >> + struct iio_chan_spec *ch; >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + int ret; >> + >> + ch = devm_kzalloc(&indio_dev->dev, sizeof(*ch), GFP_KERNEL); >> + if (!ch) >> + return -ENOMEM; >> + >> + ret = stm32_dfsdm_channel_parse_of(pdmc->dfsdm, indio_dev, ch, 0); >> + if (ret < 0) >> + return ret; >> + >> + ch->type = IIO_VOLTAGE; >> + ch->indexed = 1; >> + ch->scan_index = 0; >> + ch->ext_info = dfsdm_adc_ext_info; >> + >> + ch->scan_type.sign = 's'; >> + ch->scan_type.realbits = 24; >> + ch->scan_type.storagebits = 32; >> + >> + pdmc->ch_id = ch->channel; >> + ret = stm32_dfsdm_chan_configure(pdmc->dfsdm, >> + &pdmc->dfsdm->ch_list[ch->channel]); >> + >> + indio_dev->num_channels = 1; >> + indio_dev->channels = ch; >> + >> + return ret; >> +} >> + >> +static const struct of_device_id stm32_dfsdm_audio_match[] = { >> + { .compatible = "st,stm32-dfsdm-audio"}, >> + {} >> +}; >> + >> +static int stm32_dfsdm_audio_dma_request(struct iio_dev *indio_dev) >> +{ >> + struct stm32_dfsdm_audio *pdmc = iio_priv(indio_dev); >> + struct dma_slave_config config; >> + int ret; >> + >> + pdmc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); >> + if (!pdmc->dma_chan) >> + return -EINVAL; >> + >> + pdmc->rx_buf = dma_alloc_coherent(pdmc->dma_chan->device->dev, >> + DFSDM_DMA_BUFFER_SIZE, >> + &pdmc->dma_buf, GFP_KERNEL); >> + if (!pdmc->rx_buf) { >> + ret = -ENOMEM; >> + goto err_release; >> + } >> + >> + /* Configure DMA channel to read data register */ >> + memset(&config, 0, sizeof(config)); >> + config.src_addr = (dma_addr_t)pdmc->dfsdm->phys_base; >> + config.src_addr += DFSDM_RDATAR(pdmc->fl_id); >> + config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; >> + >> + ret = dmaengine_slave_config(pdmc->dma_chan, &config); >> + if (ret) >> + goto err_free; >> + >> + return 0; >> + >> +err_free: >> + dma_free_coherent(pdmc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE, >> + pdmc->rx_buf, pdmc->dma_buf); >> +err_release: >> + dma_release_channel(pdmc->dma_chan); >> + >> + return ret; >> +} >> + >> +static int stm32_dfsdm_audio_probe(struct platform_device *pdev) >> +{ >> + struct device *dev = &pdev->dev; >> + struct stm32_dfsdm_audio *pdmc; >> + struct device_node *np = dev->of_node; >> + struct iio_dev *iio; >> + char *name; >> + int ret, irq, val; >> + >> + iio = devm_iio_device_alloc(dev, sizeof(*pdmc)); >> + if (IS_ERR(iio)) { >> + dev_err(dev, "%s: Failed to allocate IIO\n", __func__); >> + return PTR_ERR(iio); >> + } >> + >> + pdmc = iio_priv(iio); >> + if (IS_ERR(pdmc)) { >> + dev_err(dev, "%s: Failed to allocate ADC\n", __func__); >> + return PTR_ERR(pdmc); >> + } >> + pdmc->dfsdm = dev_get_drvdata(dev->parent); >> + >> + iio->name = np->name; >> + iio->dev.parent = dev; >> + iio->dev.of_node = np; >> + iio->info = &stm32_dfsdm_info_pdmc; >> + iio->modes = INDIO_DIRECT_MODE; >> + >> + platform_set_drvdata(pdev, pdmc); >> + >> + ret = of_property_read_u32(dev->of_node, "reg", &pdmc->fl_id); >> + if (ret != 0) { >> + dev_err(dev, "Missing reg property\n"); >> + return -EINVAL; >> + } >> + >> + name = kzalloc(sizeof("dfsdm-pdm0"), GFP_KERNEL); >> + if (!name) >> + return -ENOMEM; >> + snprintf(name, sizeof("dfsdm-pdm0"), "dfsdm-pdm%d", pdmc->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); >> + ret = devm_request_irq(dev, irq, stm32_dfsdm_irq, >> + 0, pdev->name, pdmc); >> + 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; >> + } >> + pdmc->dfsdm->fl_list[pdmc->fl_id].ford = val; >> + >> + ret = of_property_read_u32(dev->of_node, "st,filter0-sync", &val); >> + if (!ret) >> + pdmc->dfsdm->fl_list[pdmc->fl_id].sync_mode = val; >> + >> + ret = stm32_dfsdm_audio_chan_init(iio); >> + if (ret < 0) >> + return ret; >> + >> + ret = stm32_dfsdm_audio_dma_request(iio); >> + if (ret) { >> + dev_err(&pdev->dev, "DMA request failed\n"); >> + return ret; >> + } >> + >> + iio->modes |= INDIO_BUFFER_SOFTWARE; >> + >> + ret = iio_triggered_buffer_setup(iio, >> + &iio_pollfunc_store_time, >> + &stm32_dfsdm_audio_trigger_handler, >> + &stm32_dfsdm_buffer_setup_ops); >> + if (ret) { >> + dev_err(&pdev->dev, "Buffer setup failed\n"); >> + goto err_dma_disable; >> + } >> + >> + ret = iio_device_register(iio); >> + if (ret) { >> + dev_err(&pdev->dev, "IIO dev register failed\n"); >> + goto err_buffer_cleanup; >> + } >> + >> + return 0; >> + >> +err_buffer_cleanup: >> + iio_triggered_buffer_cleanup(iio); >> + >> +err_dma_disable: >> + if (pdmc->dma_chan) { >> + dma_free_coherent(pdmc->dma_chan->device->dev, >> + DFSDM_DMA_BUFFER_SIZE, >> + pdmc->rx_buf, pdmc->dma_buf); >> + dma_release_channel(pdmc->dma_chan); >> + } >> + >> + return ret; >> +} >> + >> +static int stm32_dfsdm_audio_remove(struct platform_device *pdev) >> +{ >> + struct stm32_dfsdm_audio *pdmc = platform_get_drvdata(pdev); >> + struct iio_dev *iio = iio_priv_to_dev(pdmc); >> + >> + iio_device_unregister(iio); > Same as in the other driver. Can just use the devm_iio_device_register > version and drop remove. oops missing the previous comment... sorry. >> + >> + return 0; >> +} >> + >> +static struct platform_driver stm32_dfsdm_audio_driver = { >> + .driver = { >> + .name = "stm32-dfsdm-audio", >> + .of_match_table = stm32_dfsdm_audio_match, >> + }, >> + .probe = stm32_dfsdm_audio_probe, >> + .remove = stm32_dfsdm_audio_remove, >> +}; >> +module_platform_driver(stm32_dfsdm_audio_driver); >> + >> +MODULE_DESCRIPTION("STM32 sigma delta converter for PDM microphone"); >> +MODULE_AUTHOR("Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>"); >> +MODULE_LICENSE("GPL v2"); >> diff --git a/include/linux/iio/adc/stm32-dfsdm-audio.h b/include/linux/iio/adc/stm32-dfsdm-audio.h >> new file mode 100644 >> index 0000000..9b41b28 >> --- /dev/null >> +++ b/include/linux/iio/adc/stm32-dfsdm-audio.h >> @@ -0,0 +1,41 @@ >> +/* >> + * This file discribe the STM32 DFSDM IIO driver API for audio part >> + * >> + * Copyright (C) 2017, STMicroelectronics - All Rights Reserved >> + * Author(s): Arnaud Pouliquen <arnaud.pouliquen@xxxxxx>. >> + * >> + * License terms: GPL V2.0. >> + * >> + * This program is free software; you can redistribute it and/or modify it >> + * under the terms of the GNU General Public License version 2 as published by >> + * the Free Software Foundation. >> + * >> + * 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. >> + */ >> +#ifndef STM32_DFSDM_AUDIO_H >> +#define STM32_DFSDM_AUDIO_H >> + >> +/** >> + * stm32_dfsdm_get_buff_cb() - register callback for capture buffer period. >> + * @dev: Pointer to client device. >> + * @indio_dev: Device on which the channel exists. >> + * @cb: Callback function. >> + * @data: pointer to data buffer >> + * @size: size of the data buffer in bytes >> + * @private: Private data passed to callback. >> + * >> + */ >> +int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev, >> + int (*cb)(const void *data, size_t size, >> + void *private), >> + void *private); >> +/** >> + * stm32_dfsdm_get_buff_cb() - release callback for capture buffer period. >> + * @indio_dev: Device on which the channel exists. >> + */ >> +int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev); >> + >> +#endif >> > -- To unsubscribe from this list: send the line "unsubscribe linux-iio" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
