This adds a section about the Hardware consumer API of the IIO subsystem to the driver API documentation.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com Reviewed-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- Documentation/driver-api/iio/hw-consumer.rst | 51 ++++++++++++++++++++++++++++ Documentation/driver-api/iio/index.rst | 1 + 2 files changed, 52 insertions(+) create mode 100644 Documentation/driver-api/iio/hw-consumer.rst

diff --git a/Documentation/driver-api/iio/hw-consumer.rst b/Documentation/driver-api/iio/hw-consumer.rst new file mode 100644 index 0000000..8facce6 --- /dev/null +++ b/Documentation/driver-api/iio/hw-consumer.rst @@ -0,0 +1,51 @@ +=========== +HW consumer +=========== +An IIO device can be directly connected to another device in hardware. in this +case the buffers between IIO provider and IIO consumer are handled by hardware. +The Industrial I/O HW consumer offers a way to bond these IIO devices without +software buffer for data. The implementation can be found under +:file:`drivers/iio/buffer/hw-consumer.c` + + +* struct :c:type:`iio_hw_consumer` — Hardware consumer structure +* :c:func:`iio_hw_consumer_alloc` — Allocate IIO hardware consumer +* :c:func:`iio_hw_consumer_free` — Free IIO hardware consumer +* :c:func:`iio_hw_consumer_enable` — Enable IIO hardware consumer +* :c:func:`iio_hw_consumer_disable` — Disable IIO hardware consumer + + +HW consumer setup +================= + +As standard IIO device the implementation is based on IIO provider/consumer. +A typical IIO HW consumer setup looks like this:: + + static struct iio_hw_consumer *hwc; + + static const struct iio_info adc_info = { + .read_raw = adc_read_raw, + }; + + static int adc_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, int *val, + int *val2, long mask) + { + ret = iio_hw_consumer_enable(hwc); + + /* Acquire data */ + + ret = iio_hw_consumer_disable(hwc); + } + + static int adc_probe(struct platform_device *pdev) + { + hwc = devm_iio_hw_consumer_alloc(&iio->dev); + } + +More details +============ +.. kernel-doc:: include/linux/iio/hw-consumer.h +.. kernel-doc:: drivers/iio/buffer/industrialio-hw-consumer.c + :export: + diff --git a/Documentation/driver-api/iio/index.rst b/Documentation/driver-api/iio/index.rst index e5c3922..7fba341 100644 --- a/Documentation/driver-api/iio/index.rst +++ b/Documentation/driver-api/iio/index.rst @@ -15,3 +15,4 @@ Contents: buffers triggers triggered-buffers + hw-consumer

Extend the inkern API with functions for reading and writing attribute of iio channels.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com Reviewed-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- V7 to V8 - Suppress extra line.

drivers/iio/inkern.c | 17 ++++++++++++----- include/linux/iio/consumer.h | 26 ++++++++++++++++++++++++++ include/linux/iio/iio.h | 28 ---------------------------- include/linux/iio/types.h | 28 ++++++++++++++++++++++++++++ 4 files changed, 66 insertions(+), 33 deletions(-)

diff --git a/drivers/iio/inkern.c b/drivers/iio/inkern.c index 069defc..ec98790 100644 --- a/drivers/iio/inkern.c +++ b/drivers/iio/inkern.c @@ -664,9 +664,8 @@ int iio_convert_raw_to_processed(struct iio_channel *chan, int raw, } EXPORT_SYMBOL_GPL(iio_convert_raw_to_processed);

-static int iio_read_channel_attribute(struct iio_channel *chan, - int *val, int *val2, - enum iio_chan_info_enum attribute) +int iio_read_channel_attribute(struct iio_channel *chan, int *val, int *val2, + enum iio_chan_info_enum attribute) { int ret;

@@ -682,6 +681,7 @@ static int iio_read_channel_attribute(struct iio_channel *chan,

return ret; } +EXPORT_SYMBOL_GPL(iio_read_channel_attribute);

int iio_read_channel_offset(struct iio_channel *chan, int *val, int *val2) { @@ -850,7 +850,8 @@ static int iio_channel_write(struct iio_channel *chan, int val, int val2, chan->channel, val, val2, info); }

-int iio_write_channel_raw(struct iio_channel *chan, int val) +int iio_write_channel_attribute(struct iio_channel *chan, int val, int val2, + enum iio_chan_info_enum attribute) { int ret;

@@ -860,12 +861,18 @@ int iio_write_channel_raw(struct iio_channel *chan, int val) goto err_unlock; }

- ret = iio_channel_write(chan, val, 0, IIO_CHAN_INFO_RAW); + ret = iio_channel_write(chan, val, val2, attribute); err_unlock: mutex_unlock(&chan->indio_dev->info_exist_lock);

return ret; } +EXPORT_SYMBOL_GPL(iio_write_channel_attribute); + +int iio_write_channel_raw(struct iio_channel *chan, int val) +{ + return iio_write_channel_attribute(chan, val, 0, IIO_CHAN_INFO_RAW); +} EXPORT_SYMBOL_GPL(iio_write_channel_raw);

unsigned int iio_get_channel_ext_info_count(struct iio_channel *chan) diff --git a/include/linux/iio/consumer.h b/include/linux/iio/consumer.h index 5e347a9..2017f35 100644 --- a/include/linux/iio/consumer.h +++ b/include/linux/iio/consumer.h @@ -216,6 +216,32 @@ int iio_read_channel_average_raw(struct iio_channel *chan, int *val); int iio_read_channel_processed(struct iio_channel *chan, int *val);

/** + * iio_write_channel_attribute() - Write values to the device attribute. + * @chan: The channel being queried. + * @val: Value being written. + * @val2: Value being written.val2 use depends on attribute type. + * @attribute: info attribute to be read. + * + * Returns an error code or 0. + */ +int iio_write_channel_attribute(struct iio_channel *chan, int val, + int val2, enum iio_chan_info_enum attribute); + +/** + * iio_read_channel_attribute() - Read values from the device attribute. + * @chan: The channel being queried. + * @val: Value being written. + * @val2: Value being written.Val2 use depends on attribute type. + * @attribute: info attribute to be written. + * + * Returns an error code if failed. Else returns a description of what is in val + * and val2, such as IIO_VAL_INT_PLUS_MICRO telling us we have a value of val + * + val2/1e6 + */ +int iio_read_channel_attribute(struct iio_channel *chan, int *val, + int *val2, enum iio_chan_info_enum attribute); + +/** * iio_write_channel_raw() - write to a given channel * @chan: The channel being queried. * @val: Value being written. diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h index c380daa..007caf7 100644 --- a/include/linux/iio/iio.h +++ b/include/linux/iio/iio.h @@ -20,34 +20,6 @@ * Currently assumes nano seconds. */

-enum iio_chan_info_enum { - IIO_CHAN_INFO_RAW = 0, - IIO_CHAN_INFO_PROCESSED, - IIO_CHAN_INFO_SCALE, - IIO_CHAN_INFO_OFFSET, - IIO_CHAN_INFO_CALIBSCALE, - IIO_CHAN_INFO_CALIBBIAS, - IIO_CHAN_INFO_PEAK, - IIO_CHAN_INFO_PEAK_SCALE, - IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW, - IIO_CHAN_INFO_AVERAGE_RAW, - IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY, - IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY, - IIO_CHAN_INFO_SAMP_FREQ, - IIO_CHAN_INFO_FREQUENCY, - IIO_CHAN_INFO_PHASE, - IIO_CHAN_INFO_HARDWAREGAIN, - IIO_CHAN_INFO_HYSTERESIS, - IIO_CHAN_INFO_INT_TIME, - IIO_CHAN_INFO_ENABLE, - IIO_CHAN_INFO_CALIBHEIGHT, - IIO_CHAN_INFO_CALIBWEIGHT, - IIO_CHAN_INFO_DEBOUNCE_COUNT, - IIO_CHAN_INFO_DEBOUNCE_TIME, - IIO_CHAN_INFO_CALIBEMISSIVITY, - IIO_CHAN_INFO_OVERSAMPLING_RATIO, -}; - enum iio_shared_by { IIO_SEPARATE, IIO_SHARED_BY_TYPE, diff --git a/include/linux/iio/types.h b/include/linux/iio/types.h index 2aa7b63..6eb3d683 100644 --- a/include/linux/iio/types.h +++ b/include/linux/iio/types.h @@ -34,4 +34,32 @@ enum iio_available_type { IIO_AVAIL_RANGE, };

+enum iio_chan_info_enum { + IIO_CHAN_INFO_RAW = 0, + IIO_CHAN_INFO_PROCESSED, + IIO_CHAN_INFO_SCALE, + IIO_CHAN_INFO_OFFSET, + IIO_CHAN_INFO_CALIBSCALE, + IIO_CHAN_INFO_CALIBBIAS, + IIO_CHAN_INFO_PEAK, + IIO_CHAN_INFO_PEAK_SCALE, + IIO_CHAN_INFO_QUADRATURE_CORRECTION_RAW, + IIO_CHAN_INFO_AVERAGE_RAW, + IIO_CHAN_INFO_LOW_PASS_FILTER_3DB_FREQUENCY, + IIO_CHAN_INFO_HIGH_PASS_FILTER_3DB_FREQUENCY, + IIO_CHAN_INFO_SAMP_FREQ, + IIO_CHAN_INFO_FREQUENCY, + IIO_CHAN_INFO_PHASE, + IIO_CHAN_INFO_HARDWAREGAIN, + IIO_CHAN_INFO_HYSTERESIS, + IIO_CHAN_INFO_INT_TIME, + IIO_CHAN_INFO_ENABLE, + IIO_CHAN_INFO_CALIBHEIGHT, + IIO_CHAN_INFO_CALIBWEIGHT, + IIO_CHAN_INFO_DEBOUNCE_COUNT, + IIO_CHAN_INFO_DEBOUNCE_TIME, + IIO_CHAN_INFO_CALIBEMISSIVITY, + IIO_CHAN_INFO_OVERSAMPLING_RATIO, +}; + #endif /* _IIO_TYPES_H_ */

Add generic driver to support sigma delta modulators. Typically, this device is hardware connected to an IIO device in charge of the conversion. Devices are bonded through the hardware consumer API.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com Acked-by: Jonathan Cameron Jonathan.Cameron@huawei.com --- drivers/iio/adc/Kconfig | 12 +++++++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/sd_adc_modulator.c | 68 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 81 insertions(+) create mode 100644 drivers/iio/adc/sd_adc_modulator.c

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 5762565..c5db62f 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -626,6 +626,18 @@ config SPEAR_ADC To compile this driver as a module, choose M here: the module will be called spear_adc.

+config SD_ADC_MODULATOR + tristate "Generic sigma delta modulator" + depends on OF + select IIO_BUFFER + select IIO_TRIGGERED_BUFFER + help + Select this option to enables sigma delta modulator. This driver can + support generic sigma delta modulators. + + This driver can also be built as a module. If so, the module + will be called sd_adc_modulator. + config STM32_ADC_CORE tristate "STMicroelectronics STM32 adc core" depends on ARCH_STM32 || COMPILE_TEST diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index 9874e05..d800325 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -81,3 +81,4 @@ obj-$(CONFIG_VF610_ADC) += vf610_adc.o obj-$(CONFIG_VIPERBOARD_ADC) += viperboard_adc.o xilinx-xadc-y := xilinx-xadc-core.o xilinx-xadc-events.o obj-$(CONFIG_XILINX_XADC) += xilinx-xadc.o +obj-$(CONFIG_SD_ADC_MODULATOR) += sd_adc_modulator.o diff --git a/drivers/iio/adc/sd_adc_modulator.c b/drivers/iio/adc/sd_adc_modulator.c new file mode 100644 index 0000000..560d8c7 --- /dev/null +++ b/drivers/iio/adc/sd_adc_modulator.c @@ -0,0 +1,68 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Generic sigma delta modulator driver + * + * Copyright (C) 2017, STMicroelectronics - All Rights Reserved + * Author: Arnaud Pouliquen arnaud.pouliquen@st.com. + */ + +#include <linux/iio/iio.h> +#include <linux/iio/triggered_buffer.h> +#include <linux/module.h> +#include <linux/of_device.h> + +static const struct iio_info iio_sd_mod_iio_info; + +static const struct iio_chan_spec iio_sd_mod_ch = { + .type = IIO_VOLTAGE, + .indexed = 1, + .scan_type = { + .sign = 'u', + .realbits = 1, + .shift = 0, + }, +}; + +static int iio_sd_mod_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct iio_dev *iio; + + iio = devm_iio_device_alloc(dev, 0); + if (!iio) + return -ENOMEM; + + iio->dev.parent = dev; + iio->dev.of_node = dev->of_node; + iio->name = dev_name(dev); + iio->info = &iio_sd_mod_iio_info; + iio->modes = INDIO_BUFFER_HARDWARE; + + iio->num_channels = 1; + iio->channels = &iio_sd_mod_ch; + + platform_set_drvdata(pdev, iio); + + return devm_iio_device_register(&pdev->dev, iio); +} + +static const struct of_device_id sd_adc_of_match[] = { + { .compatible = "sd-modulator" }, + { .compatible = "ads1201" }, + { } +}; +MODULE_DEVICE_TABLE(of, sd_adc_of_match); + +static struct platform_driver iio_sd_mod_adc = { + .driver = { + .name = "iio_sd_adc_mod", + .of_match_table = of_match_ptr(sd_adc_of_match), + }, + .probe = iio_sd_mod_probe, +}; + +module_platform_driver(iio_sd_mod_adc); + +MODULE_DESCRIPTION("Basic sigma delta modulator"); +MODULE_AUTHOR("Arnaud Pouliquen arnaud.pouliquen@st.com"); +MODULE_LICENSE("GPL v2");

Add driver for stm32 DFSDM pheripheral. Its converts a sigma delta stream in n bit samples through a low pass filter and an integrator. stm32-dfsdm-core driver is the core part supporting the filter instances dedicated to sigma-delta ADC or audio PDM microphone purpose.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com Reviewed-by: Jonathan Cameron jonathan.cameron@huawei.com --- drivers/iio/adc/Kconfig | 12 ++ drivers/iio/adc/Makefile | 1 + drivers/iio/adc/stm32-dfsdm-core.c | 309 ++++++++++++++++++++++++++++++++++++ drivers/iio/adc/stm32-dfsdm.h | 310 +++++++++++++++++++++++++++++++++++++ 4 files changed, 632 insertions(+) create mode 100644 drivers/iio/adc/stm32-dfsdm-core.c create mode 100644 drivers/iio/adc/stm32-dfsdm.h

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index c5db62f..b729ae0 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -665,6 +665,18 @@ config STM32_ADC This driver can also be built as a module. If so, the module will be called stm32-adc.

+config STM32_DFSDM_CORE + tristate "STMicroelectronics STM32 DFSDM core" + depends on (ARCH_STM32 && OF) || COMPILE_TEST + select REGMAP + select REGMAP_MMIO + help + Select this option to enable the driver 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-core. + config STX104 tristate "Apex Embedded Systems STX104 driver" depends on PC104 && X86 && ISA_BUS_API diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile index d800325..b52d0a0 100644 --- a/drivers/iio/adc/Makefile +++ b/drivers/iio/adc/Makefile @@ -63,6 +63,7 @@ obj-$(CONFIG_STX104) += stx104.o obj-$(CONFIG_SUN4I_GPADC) += sun4i-gpadc-iio.o obj-$(CONFIG_STM32_ADC_CORE) += stm32-adc-core.o obj-$(CONFIG_STM32_ADC) += stm32-adc.o +obj-$(CONFIG_STM32_DFSDM_CORE) += stm32-dfsdm-core.o obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o obj-$(CONFIG_TI_ADC084S021) += ti-adc084s021.o diff --git a/drivers/iio/adc/stm32-dfsdm-core.c b/drivers/iio/adc/stm32-dfsdm-core.c new file mode 100644 index 0000000..7242741 --- /dev/null +++ b/drivers/iio/adc/stm32-dfsdm-core.c @@ -0,0 +1,309 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * This file is part the core part STM32 DFSDM driver + * + * Copyright (C) 2017, STMicroelectronics - All Rights Reserved + * Author(s): Arnaud Pouliquen arnaud.pouliquen@st.com for STMicroelectronics. + */ + +#include <linux/clk.h> +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/of_device.h> +#include <linux/regmap.h> +#include <linux/slab.h> + +#include "stm32-dfsdm.h" + +struct stm32_dfsdm_dev_data { + unsigned int num_filters; + unsigned int num_channels; + const struct regmap_config *regmap_cfg; +}; + +#define STM32H7_DFSDM_NUM_FILTERS 4 +#define STM32H7_DFSDM_NUM_CHANNELS 8 + +static bool stm32_dfsdm_volatile_reg(struct device *dev, unsigned int reg) +{ + if (reg < DFSDM_FILTER_BASE_ADR) + return false; + + /* + * Mask is done on register to avoid to list registers of all + * filter instances. + */ + switch (reg & DFSDM_FILTER_REG_MASK) { + case DFSDM_CR1(0) & DFSDM_FILTER_REG_MASK: + case DFSDM_ISR(0) & DFSDM_FILTER_REG_MASK: + case DFSDM_JDATAR(0) & DFSDM_FILTER_REG_MASK: + case DFSDM_RDATAR(0) & DFSDM_FILTER_REG_MASK: + return true; + } + + return false; +} + +static const struct regmap_config stm32h7_dfsdm_regmap_cfg = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = sizeof(u32), + .max_register = 0x2B8, + .volatile_reg = stm32_dfsdm_volatile_reg, + .fast_io = true, +}; + +static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_data = { + .num_filters = STM32H7_DFSDM_NUM_FILTERS, + .num_channels = STM32H7_DFSDM_NUM_CHANNELS, + .regmap_cfg = &stm32h7_dfsdm_regmap_cfg, +}; + +struct dfsdm_priv { + struct platform_device *pdev; /* platform device */ + + struct stm32_dfsdm dfsdm; /* common data exported for all instances */ + + unsigned int spi_clk_out_div; /* SPI clkout divider value */ + atomic_t n_active_ch; /* number of current active channels */ + + struct clk *clk; /* DFSDM clock */ + struct clk *aclk; /* audio clock */ +}; + +/** + * stm32_dfsdm_start_dfsdm - start global dfsdm interface. + * + * Enable interface if n_active_ch is not null. + * @dfsdm: Handle used to retrieve dfsdm context. + */ +int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm) +{ + struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm); + struct device *dev = &priv->pdev->dev; + unsigned int clk_div = priv->spi_clk_out_div; + int ret; + + if (atomic_inc_return(&priv->n_active_ch) == 1) { + ret = clk_prepare_enable(priv->clk); + if (ret < 0) { + dev_err(dev, "Failed to start clock\n"); + goto error_ret; + } + if (priv->aclk) { + ret = clk_prepare_enable(priv->aclk); + if (ret < 0) { + dev_err(dev, "Failed to start audio clock\n"); + goto disable_clk; + } + } + + /* Output the SPI CLKOUT (if clk_div == 0 clock if OFF) */ + ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0), + DFSDM_CHCFGR1_CKOUTDIV_MASK, + DFSDM_CHCFGR1_CKOUTDIV(clk_div)); + if (ret < 0) + goto disable_aclk; + + /* Global enable of DFSDM interface */ + ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0), + DFSDM_CHCFGR1_DFSDMEN_MASK, + DFSDM_CHCFGR1_DFSDMEN(1)); + if (ret < 0) + goto disable_aclk; + } + + dev_dbg(dev, "%s: n_active_ch %d\n", __func__, + atomic_read(&priv->n_active_ch)); + + return 0; + +disable_aclk: + clk_disable_unprepare(priv->aclk); +disable_clk: + clk_disable_unprepare(priv->clk); + +error_ret: + atomic_dec(&priv->n_active_ch); + + return ret; +} +EXPORT_SYMBOL_GPL(stm32_dfsdm_start_dfsdm); + +/** + * stm32_dfsdm_stop_dfsdm - stop global DFSDM interface. + * + * Disable interface if n_active_ch is null + * @dfsdm: Handle used to retrieve dfsdm context. + */ +int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm) +{ + struct dfsdm_priv *priv = container_of(dfsdm, struct dfsdm_priv, dfsdm); + int ret; + + if (atomic_dec_and_test(&priv->n_active_ch)) { + /* Global disable of DFSDM interface */ + ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0), + DFSDM_CHCFGR1_DFSDMEN_MASK, + DFSDM_CHCFGR1_DFSDMEN(0)); + if (ret < 0) + return ret; + + /* Stop SPI CLKOUT */ + ret = regmap_update_bits(dfsdm->regmap, DFSDM_CHCFGR1(0), + DFSDM_CHCFGR1_CKOUTDIV_MASK, + DFSDM_CHCFGR1_CKOUTDIV(0)); + if (ret < 0) + return ret; + + clk_disable_unprepare(priv->clk); + if (priv->aclk) + clk_disable_unprepare(priv->aclk); + } + dev_dbg(&priv->pdev->dev, "%s: n_active_ch %d\n", __func__, + atomic_read(&priv->n_active_ch)); + + return 0; +} +EXPORT_SYMBOL_GPL(stm32_dfsdm_stop_dfsdm); + +static int stm32_dfsdm_parse_of(struct platform_device *pdev, + struct dfsdm_priv *priv) +{ + struct device_node *node = pdev->dev.of_node; + struct resource *res; + unsigned long clk_freq; + unsigned int spi_freq, rem; + int ret; + + if (!node) + return -EINVAL; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) { + dev_err(&pdev->dev, "Failed to get memory resource\n"); + return -ENODEV; + } + priv->dfsdm.phys_base = res->start; + priv->dfsdm.base = devm_ioremap_resource(&pdev->dev, res); + + /* + * "dfsdm" clock is mandatory for DFSDM peripheral clocking. + * "dfsdm" or "audio" clocks can be used as source clock for + * the SPI clock out signal and internal processing, depending + * on use case. + */ + priv->clk = devm_clk_get(&pdev->dev, "dfsdm"); + if (IS_ERR(priv->clk)) { + dev_err(&pdev->dev, "No stm32_dfsdm_clk clock found\n"); + return -EINVAL; + } + + priv->aclk = devm_clk_get(&pdev->dev, "audio"); + if (IS_ERR(priv->aclk)) + priv->aclk = NULL; + + if (priv->aclk) + clk_freq = clk_get_rate(priv->aclk); + else + clk_freq = clk_get_rate(priv->clk); + + /* SPI clock out frequency */ + ret = of_property_read_u32(pdev->dev.of_node, "spi-max-frequency", + &spi_freq); + if (ret < 0) { + /* No SPI master mode */ + return 0; + } + + priv->spi_clk_out_div = div_u64_rem(clk_freq, spi_freq, &rem) - 1; + priv->dfsdm.spi_master_freq = spi_freq; + + if (rem) { + dev_warn(&pdev->dev, "SPI clock not accurate\n"); + dev_warn(&pdev->dev, "%ld = %d * %d + %d\n", + clk_freq, spi_freq, priv->spi_clk_out_div + 1, rem); + } + + return 0; +}; + +static const struct of_device_id stm32_dfsdm_of_match[] = { + { + .compatible = "st,stm32h7-dfsdm", + .data = &stm32h7_dfsdm_data, + }, + {} +}; +MODULE_DEVICE_TABLE(of, stm32_dfsdm_of_match); + +static int stm32_dfsdm_probe(struct platform_device *pdev) +{ + struct dfsdm_priv *priv; + struct device_node *pnode = pdev->dev.of_node; + const struct of_device_id *of_id; + const struct stm32_dfsdm_dev_data *dev_data; + struct stm32_dfsdm *dfsdm; + int ret; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->pdev = pdev; + + of_id = of_match_node(stm32_dfsdm_of_match, pnode); + if (!of_id->data) { + dev_err(&pdev->dev, "Data associated to device is missing\n"); + return -EINVAL; + } + + dev_data = (const struct stm32_dfsdm_dev_data *)of_id->data; + dfsdm = &priv->dfsdm; + dfsdm->fl_list = devm_kcalloc(&pdev->dev, dev_data->num_filters, + sizeof(*dfsdm->fl_list), GFP_KERNEL); + if (!dfsdm->fl_list) + return -ENOMEM; + + dfsdm->num_fls = dev_data->num_filters; + dfsdm->ch_list = devm_kcalloc(&pdev->dev, dev_data->num_channels, + sizeof(*dfsdm->ch_list), + GFP_KERNEL); + if (!dfsdm->ch_list) + return -ENOMEM; + dfsdm->num_chs = dev_data->num_channels; + + ret = stm32_dfsdm_parse_of(pdev, priv); + if (ret < 0) + return ret; + + dfsdm->regmap = devm_regmap_init_mmio_clk(&pdev->dev, "dfsdm", + dfsdm->base, + &stm32h7_dfsdm_regmap_cfg); + if (IS_ERR(dfsdm->regmap)) { + ret = PTR_ERR(dfsdm->regmap); + dev_err(&pdev->dev, "%s: Failed to allocate regmap: %d\n", + __func__, ret); + return ret; + } + + platform_set_drvdata(pdev, dfsdm); + + return devm_of_platform_populate(&pdev->dev); +} + +static struct platform_driver stm32_dfsdm_driver = { + .probe = stm32_dfsdm_probe, + .driver = { + .name = "stm32-dfsdm", + .of_match_table = stm32_dfsdm_of_match, + }, +}; + +module_platform_driver(stm32_dfsdm_driver); + +MODULE_AUTHOR("Arnaud Pouliquen arnaud.pouliquen@st.com"); +MODULE_DESCRIPTION("STMicroelectronics STM32 dfsdm driver"); +MODULE_LICENSE("GPL v2"); diff --git a/drivers/iio/adc/stm32-dfsdm.h b/drivers/iio/adc/stm32-dfsdm.h new file mode 100644 index 0000000..8708394 --- /dev/null +++ b/drivers/iio/adc/stm32-dfsdm.h @@ -0,0 +1,310 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * This file is part of STM32 DFSDM driver + * + * Copyright (C) 2017, STMicroelectronics - All Rights Reserved + * Author(s): Arnaud Pouliquen arnaud.pouliquen@st.com. + */ + +#ifndef MDF_STM32_DFSDM__H +#define MDF_STM32_DFSDM__H + +#include <linux/bitfield.h> + +/* + * STM32 DFSDM - global register map + * ________________________________________________________ + * | Offset | Registers block | + * -------------------------------------------------------- + * | 0x000 | CHANNEL 0 + COMMON CHANNEL FIELDS | + * -------------------------------------------------------- + * | 0x020 | CHANNEL 1 | + * -------------------------------------------------------- + * | ... | ..... | + * -------------------------------------------------------- + * | 0x0E0 | CHANNEL 7 | + * -------------------------------------------------------- + * | 0x100 | FILTER 0 + COMMON FILTER FIELDs | + * -------------------------------------------------------- + * | 0x200 | FILTER 1 | + * -------------------------------------------------------- + * | 0x300 | FILTER 2 | + * -------------------------------------------------------- + * | 0x400 | FILTER 3 | + * -------------------------------------------------------- + */ + +/* + * Channels register definitions + */ +#define DFSDM_CHCFGR1(y) ((y) * 0x20 + 0x00) +#define DFSDM_CHCFGR2(y) ((y) * 0x20 + 0x04) +#define DFSDM_AWSCDR(y) ((y) * 0x20 + 0x08) +#define DFSDM_CHWDATR(y) ((y) * 0x20 + 0x0C) +#define DFSDM_CHDATINR(y) ((y) * 0x20 + 0x10) + +/* CHCFGR1: Channel configuration register 1 */ +#define DFSDM_CHCFGR1_SITP_MASK GENMASK(1, 0) +#define DFSDM_CHCFGR1_SITP(v) FIELD_PREP(DFSDM_CHCFGR1_SITP_MASK, v) +#define DFSDM_CHCFGR1_SPICKSEL_MASK GENMASK(3, 2) +#define DFSDM_CHCFGR1_SPICKSEL(v) FIELD_PREP(DFSDM_CHCFGR1_SPICKSEL_MASK, v) +#define DFSDM_CHCFGR1_SCDEN_MASK BIT(5) +#define DFSDM_CHCFGR1_SCDEN(v) FIELD_PREP(DFSDM_CHCFGR1_SCDEN_MASK, v) +#define DFSDM_CHCFGR1_CKABEN_MASK BIT(6) +#define DFSDM_CHCFGR1_CKABEN(v) FIELD_PREP(DFSDM_CHCFGR1_CKABEN_MASK, v) +#define DFSDM_CHCFGR1_CHEN_MASK BIT(7) +#define DFSDM_CHCFGR1_CHEN(v) FIELD_PREP(DFSDM_CHCFGR1_CHEN_MASK, v) +#define DFSDM_CHCFGR1_CHINSEL_MASK BIT(8) +#define DFSDM_CHCFGR1_CHINSEL(v) FIELD_PREP(DFSDM_CHCFGR1_CHINSEL_MASK, v) +#define DFSDM_CHCFGR1_DATMPX_MASK GENMASK(13, 12) +#define DFSDM_CHCFGR1_DATMPX(v) FIELD_PREP(DFSDM_CHCFGR1_DATMPX_MASK, v) +#define DFSDM_CHCFGR1_DATPACK_MASK GENMASK(15, 14) +#define DFSDM_CHCFGR1_DATPACK(v) FIELD_PREP(DFSDM_CHCFGR1_DATPACK_MASK, v) +#define DFSDM_CHCFGR1_CKOUTDIV_MASK GENMASK(23, 16) +#define DFSDM_CHCFGR1_CKOUTDIV(v) FIELD_PREP(DFSDM_CHCFGR1_CKOUTDIV_MASK, v) +#define DFSDM_CHCFGR1_CKOUTSRC_MASK BIT(30) +#define DFSDM_CHCFGR1_CKOUTSRC(v) FIELD_PREP(DFSDM_CHCFGR1_CKOUTSRC_MASK, v) +#define DFSDM_CHCFGR1_DFSDMEN_MASK BIT(31) +#define DFSDM_CHCFGR1_DFSDMEN(v) FIELD_PREP(DFSDM_CHCFGR1_DFSDMEN_MASK, v) + +/* CHCFGR2: Channel configuration register 2 */ +#define DFSDM_CHCFGR2_DTRBS_MASK GENMASK(7, 3) +#define DFSDM_CHCFGR2_DTRBS(v) FIELD_PREP(DFSDM_CHCFGR2_DTRBS_MASK, v) +#define DFSDM_CHCFGR2_OFFSET_MASK GENMASK(31, 8) +#define DFSDM_CHCFGR2_OFFSET(v) FIELD_PREP(DFSDM_CHCFGR2_OFFSET_MASK, v) + +/* AWSCDR: Channel analog watchdog and short circuit detector */ +#define DFSDM_AWSCDR_SCDT_MASK GENMASK(7, 0) +#define DFSDM_AWSCDR_SCDT(v) FIELD_PREP(DFSDM_AWSCDR_SCDT_MASK, v) +#define DFSDM_AWSCDR_BKSCD_MASK GENMASK(15, 12) +#define DFSDM_AWSCDR_BKSCD(v) FIELD_PREP(DFSDM_AWSCDR_BKSCD_MASK, v) +#define DFSDM_AWSCDR_AWFOSR_MASK GENMASK(20, 16) +#define DFSDM_AWSCDR_AWFOSR(v) FIELD_PREP(DFSDM_AWSCDR_AWFOSR_MASK, v) +#define DFSDM_AWSCDR_AWFORD_MASK GENMASK(23, 22) +#define DFSDM_AWSCDR_AWFORD(v) FIELD_PREP(DFSDM_AWSCDR_AWFORD_MASK, v) + +/* + * Filters register definitions + */ +#define DFSDM_FILTER_BASE_ADR 0x100 +#define DFSDM_FILTER_REG_MASK 0x7F +#define DFSDM_FILTER_X_BASE_ADR(x) ((x) * 0x80 + DFSDM_FILTER_BASE_ADR) + +#define DFSDM_CR1(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x00) +#define DFSDM_CR2(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x04) +#define DFSDM_ISR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x08) +#define DFSDM_ICR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x0C) +#define DFSDM_JCHGR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x10) +#define DFSDM_FCR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x14) +#define DFSDM_JDATAR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x18) +#define DFSDM_RDATAR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x1C) +#define DFSDM_AWHTR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x20) +#define DFSDM_AWLTR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x24) +#define DFSDM_AWSR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x28) +#define DFSDM_AWCFR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x2C) +#define DFSDM_EXMAX(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x30) +#define DFSDM_EXMIN(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x34) +#define DFSDM_CNVTIMR(x) (DFSDM_FILTER_X_BASE_ADR(x) + 0x38) + +/* CR1 Control register 1 */ +#define DFSDM_CR1_DFEN_MASK BIT(0) +#define DFSDM_CR1_DFEN(v) FIELD_PREP(DFSDM_CR1_DFEN_MASK, v) +#define DFSDM_CR1_JSWSTART_MASK BIT(1) +#define DFSDM_CR1_JSWSTART(v) FIELD_PREP(DFSDM_CR1_JSWSTART_MASK, v) +#define DFSDM_CR1_JSYNC_MASK BIT(3) +#define DFSDM_CR1_JSYNC(v) FIELD_PREP(DFSDM_CR1_JSYNC_MASK, v) +#define DFSDM_CR1_JSCAN_MASK BIT(4) +#define DFSDM_CR1_JSCAN(v) FIELD_PREP(DFSDM_CR1_JSCAN_MASK, v) +#define DFSDM_CR1_JDMAEN_MASK BIT(5) +#define DFSDM_CR1_JDMAEN(v) FIELD_PREP(DFSDM_CR1_JDMAEN_MASK, v) +#define DFSDM_CR1_JEXTSEL_MASK GENMASK(12, 8) +#define DFSDM_CR1_JEXTSEL(v) FIELD_PREP(DFSDM_CR1_JEXTSEL_MASK, v) +#define DFSDM_CR1_JEXTEN_MASK GENMASK(14, 13) +#define DFSDM_CR1_JEXTEN(v) FIELD_PREP(DFSDM_CR1_JEXTEN_MASK, v) +#define DFSDM_CR1_RSWSTART_MASK BIT(17) +#define DFSDM_CR1_RSWSTART(v) FIELD_PREP(DFSDM_CR1_RSWSTART_MASK, v) +#define DFSDM_CR1_RCONT_MASK BIT(18) +#define DFSDM_CR1_RCONT(v) FIELD_PREP(DFSDM_CR1_RCONT_MASK, v) +#define DFSDM_CR1_RSYNC_MASK BIT(19) +#define DFSDM_CR1_RSYNC(v) FIELD_PREP(DFSDM_CR1_RSYNC_MASK, v) +#define DFSDM_CR1_RDMAEN_MASK BIT(21) +#define DFSDM_CR1_RDMAEN(v) FIELD_PREP(DFSDM_CR1_RDMAEN_MASK, v) +#define DFSDM_CR1_RCH_MASK GENMASK(26, 24) +#define DFSDM_CR1_RCH(v) FIELD_PREP(DFSDM_CR1_RCH_MASK, v) +#define DFSDM_CR1_FAST_MASK BIT(29) +#define DFSDM_CR1_FAST(v) FIELD_PREP(DFSDM_CR1_FAST_MASK, v) +#define DFSDM_CR1_AWFSEL_MASK BIT(30) +#define DFSDM_CR1_AWFSEL(v) FIELD_PREP(DFSDM_CR1_AWFSEL_MASK, v) + +/* CR2: Control register 2 */ +#define DFSDM_CR2_IE_MASK GENMASK(6, 0) +#define DFSDM_CR2_IE(v) FIELD_PREP(DFSDM_CR2_IE_MASK, v) +#define DFSDM_CR2_JEOCIE_MASK BIT(0) +#define DFSDM_CR2_JEOCIE(v) FIELD_PREP(DFSDM_CR2_JEOCIE_MASK, v) +#define DFSDM_CR2_REOCIE_MASK BIT(1) +#define DFSDM_CR2_REOCIE(v) FIELD_PREP(DFSDM_CR2_REOCIE_MASK, v) +#define DFSDM_CR2_JOVRIE_MASK BIT(2) +#define DFSDM_CR2_JOVRIE(v) FIELD_PREP(DFSDM_CR2_JOVRIE_MASK, v) +#define DFSDM_CR2_ROVRIE_MASK BIT(3) +#define DFSDM_CR2_ROVRIE(v) FIELD_PREP(DFSDM_CR2_ROVRIE_MASK, v) +#define DFSDM_CR2_AWDIE_MASK BIT(4) +#define DFSDM_CR2_AWDIE(v) FIELD_PREP(DFSDM_CR2_AWDIE_MASK, v) +#define DFSDM_CR2_SCDIE_MASK BIT(5) +#define DFSDM_CR2_SCDIE(v) FIELD_PREP(DFSDM_CR2_SCDIE_MASK, v) +#define DFSDM_CR2_CKABIE_MASK BIT(6) +#define DFSDM_CR2_CKABIE(v) FIELD_PREP(DFSDM_CR2_CKABIE_MASK, v) +#define DFSDM_CR2_EXCH_MASK GENMASK(15, 8) +#define DFSDM_CR2_EXCH(v) FIELD_PREP(DFSDM_CR2_EXCH_MASK, v) +#define DFSDM_CR2_AWDCH_MASK GENMASK(23, 16) +#define DFSDM_CR2_AWDCH(v) FIELD_PREP(DFSDM_CR2_AWDCH_MASK, v) + +/* ISR: Interrupt status register */ +#define DFSDM_ISR_JEOCF_MASK BIT(0) +#define DFSDM_ISR_JEOCF(v) FIELD_PREP(DFSDM_ISR_JEOCF_MASK, v) +#define DFSDM_ISR_REOCF_MASK BIT(1) +#define DFSDM_ISR_REOCF(v) FIELD_PREP(DFSDM_ISR_REOCF_MASK, v) +#define DFSDM_ISR_JOVRF_MASK BIT(2) +#define DFSDM_ISR_JOVRF(v) FIELD_PREP(DFSDM_ISR_JOVRF_MASK, v) +#define DFSDM_ISR_ROVRF_MASK BIT(3) +#define DFSDM_ISR_ROVRF(v) FIELD_PREP(DFSDM_ISR_ROVRF_MASK, v) +#define DFSDM_ISR_AWDF_MASK BIT(4) +#define DFSDM_ISR_AWDF(v) FIELD_PREP(DFSDM_ISR_AWDF_MASK, v) +#define DFSDM_ISR_JCIP_MASK BIT(13) +#define DFSDM_ISR_JCIP(v) FIELD_PREP(DFSDM_ISR_JCIP_MASK, v) +#define DFSDM_ISR_RCIP_MASK BIT(14) +#define DFSDM_ISR_RCIP(v) FIELD_PREP(DFSDM_ISR_RCIP, v) +#define DFSDM_ISR_CKABF_MASK GENMASK(23, 16) +#define DFSDM_ISR_CKABF(v) FIELD_PREP(DFSDM_ISR_CKABF_MASK, v) +#define DFSDM_ISR_SCDF_MASK GENMASK(31, 24) +#define DFSDM_ISR_SCDF(v) FIELD_PREP(DFSDM_ISR_SCDF_MASK, v) + +/* ICR: Interrupt flag clear register */ +#define DFSDM_ICR_CLRJOVRF_MASK BIT(2) +#define DFSDM_ICR_CLRJOVRF(v) FIELD_PREP(DFSDM_ICR_CLRJOVRF_MASK, v) +#define DFSDM_ICR_CLRROVRF_MASK BIT(3) +#define DFSDM_ICR_CLRROVRF(v) FIELD_PREP(DFSDM_ICR_CLRROVRF_MASK, v) +#define DFSDM_ICR_CLRCKABF_MASK GENMASK(23, 16) +#define DFSDM_ICR_CLRCKABF(v) FIELD_PREP(DFSDM_ICR_CLRCKABF_MASK, v) +#define DFSDM_ICR_CLRCKABF_CH_MASK(y) BIT(16 + (y)) +#define DFSDM_ICR_CLRCKABF_CH(v, y) \ + (((v) << (16 + (y))) & DFSDM_ICR_CLRCKABF_CH_MASK(y)) +#define DFSDM_ICR_CLRSCDF_MASK GENMASK(31, 24) +#define DFSDM_ICR_CLRSCDF(v) FIELD_PREP(DFSDM_ICR_CLRSCDF_MASK, v) +#define DFSDM_ICR_CLRSCDF_CH_MASK(y) BIT(24 + (y)) +#define DFSDM_ICR_CLRSCDF_CH(v, y) \ + (((v) << (24 + (y))) & DFSDM_ICR_CLRSCDF_MASK(y)) + +/* FCR: Filter control register */ +#define DFSDM_FCR_IOSR_MASK GENMASK(7, 0) +#define DFSDM_FCR_IOSR(v) FIELD_PREP(DFSDM_FCR_IOSR_MASK, v) +#define DFSDM_FCR_FOSR_MASK GENMASK(25, 16) +#define DFSDM_FCR_FOSR(v) FIELD_PREP(DFSDM_FCR_FOSR_MASK, v) +#define DFSDM_FCR_FORD_MASK GENMASK(31, 29) +#define DFSDM_FCR_FORD(v) FIELD_PREP(DFSDM_FCR_FORD_MASK, v) + +/* RDATAR: Filter data register for regular channel */ +#define DFSDM_DATAR_CH_MASK GENMASK(2, 0) +#define DFSDM_DATAR_DATA_OFFSET 8 +#define DFSDM_DATAR_DATA_MASK GENMASK(31, DFSDM_DATAR_DATA_OFFSET) + +/* AWLTR: Filter analog watchdog low threshold register */ +#define DFSDM_AWLTR_BKAWL_MASK GENMASK(3, 0) +#define DFSDM_AWLTR_BKAWL(v) FIELD_PREP(DFSDM_AWLTR_BKAWL_MASK, v) +#define DFSDM_AWLTR_AWLT_MASK GENMASK(31, 8) +#define DFSDM_AWLTR_AWLT(v) FIELD_PREP(DFSDM_AWLTR_AWLT_MASK, v) + +/* AWHTR: Filter analog watchdog low threshold register */ +#define DFSDM_AWHTR_BKAWH_MASK GENMASK(3, 0) +#define DFSDM_AWHTR_BKAWH(v) FIELD_PREP(DFSDM_AWHTR_BKAWH_MASK, v) +#define DFSDM_AWHTR_AWHT_MASK GENMASK(31, 8) +#define DFSDM_AWHTR_AWHT(v) FIELD_PREP(DFSDM_AWHTR_AWHT_MASK, v) + +/* AWSR: Filter watchdog status register */ +#define DFSDM_AWSR_AWLTF_MASK GENMASK(7, 0) +#define DFSDM_AWSR_AWLTF(v) FIELD_PREP(DFSDM_AWSR_AWLTF_MASK, v) +#define DFSDM_AWSR_AWHTF_MASK GENMASK(15, 8) +#define DFSDM_AWSR_AWHTF(v) FIELD_PREP(DFSDM_AWSR_AWHTF_MASK, v) + +/* AWCFR: Filter watchdog status register */ +#define DFSDM_AWCFR_AWLTF_MASK GENMASK(7, 0) +#define DFSDM_AWCFR_AWLTF(v) FIELD_PREP(DFSDM_AWCFR_AWLTF_MASK, v) +#define DFSDM_AWCFR_AWHTF_MASK GENMASK(15, 8) +#define DFSDM_AWCFR_AWHTF(v) FIELD_PREP(DFSDM_AWCFR_AWHTF_MASK, v) + +/* DFSDM filter order */ +enum stm32_dfsdm_sinc_order { + DFSDM_FASTSINC_ORDER, /* FastSinc filter type */ + DFSDM_SINC1_ORDER, /* Sinc 1 filter type */ + DFSDM_SINC2_ORDER, /* Sinc 2 filter type */ + DFSDM_SINC3_ORDER, /* Sinc 3 filter type */ + DFSDM_SINC4_ORDER, /* Sinc 4 filter type (N.A. for watchdog) */ + DFSDM_SINC5_ORDER, /* Sinc 5 filter type (N.A. for watchdog) */ + DFSDM_NB_SINC_ORDER, +}; + +/** + * struct stm32_dfsdm_filter - structure relative to stm32 FDSDM filter + * @iosr: integrator oversampling + * @fosr: filter oversampling + * @ford: filter order + * @res: output sample resolution + * @sync_mode: filter synchronized with filter 0 + * @fast: filter fast mode + */ +struct stm32_dfsdm_filter { + unsigned int iosr; + unsigned int fosr; + enum stm32_dfsdm_sinc_order ford; + u64 res; + unsigned int sync_mode; + unsigned int fast; +}; + +/** + * struct stm32_dfsdm_channel - structure relative to stm32 FDSDM channel + * @id: id of the channel + * @type: interface type linked to stm32_dfsdm_chan_type + * @src: interface type linked to stm32_dfsdm_chan_src + * @alt_si: alternative serial input interface + */ +struct stm32_dfsdm_channel { + unsigned int id; + unsigned int type; + unsigned int src; + unsigned int alt_si; +}; + +/** + * struct stm32_dfsdm - stm32 FDSDM driver common data (for all instances) + * @base: control registers base cpu addr + * @phys_base: DFSDM IP register physical address + * @regmap: regmap for register read/write + * @fl_list: filter resources list + * @num_fls: number of filter resources available + * @ch_list: channel resources list + * @num_chs: number of channel resources available + * @spi_master_freq: SPI clock out frequency + */ +struct stm32_dfsdm { + void __iomem *base; + phys_addr_t phys_base; + struct regmap *regmap; + struct stm32_dfsdm_filter *fl_list; + unsigned int num_fls; + struct stm32_dfsdm_channel *ch_list; + unsigned int num_chs; + unsigned int spi_master_freq; +}; + +/* DFSDM channel serial spi clock source */ +enum stm32_dfsdm_spi_clk_src { + DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL, + DFSDM_CHANNEL_SPI_CLOCK_INTERNAL, + DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING, + DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING +}; + +int stm32_dfsdm_start_dfsdm(struct stm32_dfsdm *dfsdm); +int stm32_dfsdm_stop_dfsdm(struct stm32_dfsdm *dfsdm); + +#endif

This code offers a way to handle PDM audio microphones in ASOC framework. Audio driver should use consumer API. A specific management is implemented for DMA, with a callback, to allows to handle audio buffers efficiently.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com --- .../ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 | 16 + drivers/iio/adc/stm32-dfsdm-adc.c | 508 ++++++++++++++++++++- include/linux/iio/adc/stm32-dfsdm-adc.h | 18 + 3 files changed, 534 insertions(+), 8 deletions(-) create mode 100644 Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 create mode 100644 include/linux/iio/adc/stm32-dfsdm-adc.h

diff --git a/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 new file mode 100644 index 0000000..da98223 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-bus-iio-dfsdm-adc-stm32 @@ -0,0 +1,16 @@ +What: /sys/bus/iio/devices/iio:deviceX/in_voltage_spi_clk_freq +KernelVersion: 4.14 +Contact: arnaud.pouliquen@st.com +Description: + For audio purpose only. + Used by audio driver to set/get the spi input frequency. + This is mandatory if DFSDM is slave on SPI bus, to + provide information on the SPI clock frequency during runtime + Notice that the SPI frequency should be a multiple of sample + frequency to ensure the precision. + if DFSDM input is SPI master + Reading SPI clkout frequency, + error on writing + If DFSDM input is SPI Slave: + Reading returns value previously set. + Writing value before starting conversions. \ No newline at end of file diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c index 68b5920..2d6aed5 100644 --- a/drivers/iio/adc/stm32-dfsdm-adc.c +++ b/drivers/iio/adc/stm32-dfsdm-adc.c @@ -6,19 +6,25 @@ * Author: Arnaud Pouliquen arnaud.pouliquen@st.com. */

+#include <linux/dmaengine.h> +#include <linux/dma-mapping.h> #include <linux/interrupt.h> #include <linux/iio/buffer.h> #include <linux/iio/hw-consumer.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> +#include <linux/iio/trigger_consumer.h> +#include <linux/iio/triggered_buffer.h> #include <linux/module.h> -#include <linux/of.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)) @@ -58,6 +64,18 @@ struct stm32_dfsdm_adc { 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 { @@ -351,10 +369,63 @@ int stm32_dfsdm_channel_parse_of(struct stm32_dfsdm *dfsdm, 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 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_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; + struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[adc->ch_id]; + 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) { + 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; + } + } + adc->spi_freq = spi_freq; + + return len; +} + static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, bool dma) { struct regmap *regmap = adc->dfsdm->regmap; int ret; + unsigned int dma_en = 0, cont_en = 0;

ret = stm32_dfsdm_start_channel(adc->dfsdm, adc->ch_id); if (ret < 0) @@ -365,6 +436,24 @@ static int stm32_dfsdm_start_conv(struct stm32_dfsdm_adc *adc, bool dma) if (ret < 0) goto stop_channels;

+ if (dma) { + /* Enable DMA transfer*/ + dma_en = DFSDM_CR1_RDMAEN(1); + /* Enable conversion triggered by SPI clock*/ + cont_en = DFSDM_CR1_RCONT(1); + } + /* Enable DMA transfer*/ + ret = regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), + DFSDM_CR1_RDMAEN_MASK, dma_en); + if (ret < 0) + goto stop_channels; + + /* Enable conversion triggered by SPI clock*/ + ret = regmap_update_bits(regmap, DFSDM_CR1(adc->fl_id), + DFSDM_CR1_RCONT_MASK, cont_en); + if (ret < 0) + goto stop_channels; + ret = stm32_dfsdm_start_filter(adc->dfsdm, adc->fl_id); if (ret < 0) goto stop_channels; @@ -398,6 +487,231 @@ static void stm32_dfsdm_stop_conv(struct stm32_dfsdm_adc *adc) stm32_dfsdm_stop_channel(adc->dfsdm, adc->ch_id); }

+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; + + /* + * 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 = watermark * 2; + + 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 void stm32_dfsdm_audio_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) { + u32 *buffer = (u32 *)&adc->rx_buf[adc->bufi]; + + /* Mask 8 LSB that contains the channel ID */ + *buffer = (*buffer & 0xFFFFFF00) << 8; + 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; + } + } + 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); + 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); + + /* 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_audio_dma_buffer_done; + desc->callback_param = indio_dev; + + cookie = dmaengine_submit(desc); + ret = dma_submit_error(cookie); + if (ret) { + dmaengine_terminate_all(adc->dma_chan); + return ret; + } + + /* Issue pending DMA requests */ + dma_async_issue_pending(adc->dma_chan); + + 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; + + ret = stm32_dfsdm_start_dfsdm(adc->dfsdm); + if (ret < 0) + return ret; + + ret = stm32_dfsdm_start_conv(adc, true); + if (ret) { + dev_err(&indio_dev->dev, "Can't start conversion\n"); + goto stop_dfsdm; + } + + if (adc->dma_chan) { + ret = stm32_dfsdm_adc_dma_start(indio_dev); + if (ret) { + dev_err(&indio_dev->dev, "Can't start DMA\n"); + goto err_stop_conv; + } + } + + return 0; + +err_stop_conv: + stm32_dfsdm_stop_conv(adc); +stop_dfsdm: + stm32_dfsdm_stop_dfsdm(adc->dfsdm); + + return ret; +} + +static int stm32_dfsdm_predisable(struct iio_dev *indio_dev) +{ + struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + + if (adc->dma_chan) + dmaengine_terminate_all(adc->dma_chan); + + stm32_dfsdm_stop_conv(adc); + + stm32_dfsdm_stop_dfsdm(adc->dfsdm); + + 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) { @@ -453,15 +767,41 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev, { struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id]; + struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[adc->ch_id]; + unsigned int spi_freq = adc->spi_freq; int ret = -EINVAL;

- if (mask == IIO_CHAN_INFO_OVERSAMPLING_RATIO) { + switch (mask) { + case IIO_CHAN_INFO_OVERSAMPLING_RATIO: ret = stm32_dfsdm_set_osrs(fl, 0, val); if (!ret) adc->oversamp = val; + + return ret; + + case IIO_CHAN_INFO_SAMP_FREQ: + if (!val) + return -EINVAL; + if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL) + spi_freq = adc->dfsdm->spi_master_freq; + + if (spi_freq % val) + dev_warn(&indio_dev->dev, + "Sampling rate not accurate (%d)\n", + spi_freq / (spi_freq / val)); + + ret = stm32_dfsdm_set_osrs(fl, 0, (spi_freq / val)); + if (ret < 0) { + dev_err(&indio_dev->dev, + "Not able to find parameter that match!\n"); + return ret; + } + adc->sample_freq = val; + + return 0; }

- return ret; + return -EINVAL; }

static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, @@ -494,11 +834,22 @@ static int stm32_dfsdm_read_raw(struct iio_dev *indio_dev, *val = adc->oversamp;

return IIO_VAL_INT; + + case IIO_CHAN_INFO_SAMP_FREQ: + *val = adc->sample_freq; + + return IIO_VAL_INT; }

return -EINVAL; }

+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, +}; + static const struct iio_info stm32_dfsdm_info_adc = { .read_raw = stm32_dfsdm_read_raw, .write_raw = stm32_dfsdm_write_raw, @@ -531,6 +882,60 @@ static irqreturn_t stm32_dfsdm_irq(int irq, void *arg) 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 int stm32_dfsdm_dma_request(struct iio_dev *indio_dev) +{ + struct stm32_dfsdm_adc *adc = iio_priv(indio_dev); + struct dma_slave_config config; + int ret; + + adc->dma_chan = dma_request_slave_channel(&indio_dev->dev, "rx"); + if (!adc->dma_chan) + return -EINVAL; + + adc->rx_buf = dma_alloc_coherent(adc->dma_chan->device->dev, + DFSDM_DMA_BUFFER_SIZE, + &adc->dma_buf, GFP_KERNEL); + if (!adc->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)adc->dfsdm->phys_base; + config.src_addr += DFSDM_RDATAR(adc->fl_id); + config.src_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES; + + ret = dmaengine_slave_config(adc->dma_chan, &config); + if (ret) + goto err_free; + + return 0; + +err_free: + dma_free_coherent(adc->dma_chan->device->dev, DFSDM_DMA_BUFFER_SIZE, + adc->rx_buf, adc->dma_buf); +err_release: + dma_release_channel(adc->dma_chan); + + return ret; +} + static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, struct iio_chan_spec *ch) { @@ -551,7 +956,12 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, ch->info_mask_separate = BIT(IIO_CHAN_INFO_RAW); ch->info_mask_shared_by_all = BIT(IIO_CHAN_INFO_OVERSAMPLING_RATIO);

- ch->scan_type.sign = 'u'; + if (adc->dev_data->type == DFSDM_AUDIO) { + ch->scan_type.sign = 's'; + ch->ext_info = dfsdm_adc_audio_ext_info; + } else { + ch->scan_type.sign = 'u'; + } ch->scan_type.realbits = 24; ch->scan_type.storagebits = 32; adc->ch_id = ch->channel; @@ -560,6 +970,64 @@ static int stm32_dfsdm_adc_chan_init_one(struct iio_dev *indio_dev, &adc->dfsdm->ch_list[ch->channel]); }

+static int stm32_dfsdm_audio_init(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; + + ret = stm32_dfsdm_dma_request(indio_dev); + if (ret) { + dev_err(&indio_dev->dev, "DMA request failed\n"); + return ret; + } + + indio_dev->modes |= INDIO_BUFFER_SOFTWARE; + + ret = iio_triggered_buffer_setup(indio_dev, + &iio_pollfunc_store_time, + NULL, + &stm32_dfsdm_buffer_setup_ops); + if (ret) { + dev_err(&indio_dev->dev, "Buffer setup failed\n"); + goto err_dma_disable; + } + + 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"); + goto err_buffer_cleanup; + } + ch->info_mask_separate = BIT(IIO_CHAN_INFO_SAMP_FREQ); + + d_ch = &adc->dfsdm->ch_list[adc->ch_id]; + 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 0; + +err_buffer_cleanup: + iio_triggered_buffer_cleanup(indio_dev); + +err_dma_disable: + 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); + } + return ret; +} + static int stm32_dfsdm_adc_init(struct iio_dev *indio_dev) { struct iio_chan_spec *ch; @@ -612,11 +1080,20 @@ static const struct stm32_dfsdm_dev_data stm32h7_dfsdm_adc_data = { .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, + }, {} };

@@ -667,8 +1144,13 @@ static int stm32_dfsdm_adc_probe(struct platform_device *pdev) name = devm_kzalloc(dev, sizeof("dfsdm-adc0"), GFP_KERNEL); if (!name) return -ENOMEM; - iio->info = &stm32_dfsdm_info_adc; - snprintf(name, sizeof("dfsdm-adc0"), "dfsdm-adc%d", adc->fl_id); + 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;

/* @@ -700,7 +1182,10 @@ static int stm32_dfsdm_adc_probe(struct platform_device *pdev) if (ret < 0) return ret;

- return iio_device_register(iio); + iio_device_register(iio); + if (dev_data->type == DFSDM_AUDIO) + return devm_of_platform_populate(&pdev->dev); + return 0; }

static int stm32_dfsdm_adc_remove(struct platform_device *pdev) @@ -709,7 +1194,14 @@ static int stm32_dfsdm_adc_remove(struct platform_device *pdev) struct iio_dev *indio_dev = iio_priv_to_dev(adc);

iio_device_unregister(indio_dev); - + if (indio_dev->pollfunc) + iio_triggered_buffer_cleanup(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); + } return 0; }

diff --git a/include/linux/iio/adc/stm32-dfsdm-adc.h b/include/linux/iio/adc/stm32-dfsdm-adc.h new file mode 100644 index 0000000..e7dc7a5 --- /dev/null +++ b/include/linux/iio/adc/stm32-dfsdm-adc.h @@ -0,0 +1,18 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * 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@st.com. + */ + +#ifndef STM32_DFSDM_ADC_H +#define STM32_DFSDM_ADC_H + +int stm32_dfsdm_get_buff_cb(struct iio_dev *iio_dev, + int (*cb)(const void *data, size_t size, + void *private), + void *private); +int stm32_dfsdm_release_buff_cb(struct iio_dev *iio_dev); + +#endif

Add bindings that describes audio settings to support Digital Filter for pulse density modulation(PDM) microphone.

Signed-off-by: Arnaud Pouliquen arnaud.pouliquen@st.com Acked-by: Rob Herring robh@kernel.org --- .../devicetree/bindings/sound/st,stm32-adfsdm.txt | 63 ++++++++++++++++++++++ 1 file changed, 63 insertions(+) create mode 100644 Documentation/devicetree/bindings/sound/st,stm32-adfsdm.txt

diff --git a/Documentation/devicetree/bindings/sound/st,stm32-adfsdm.txt b/Documentation/devicetree/bindings/sound/st,stm32-adfsdm.txt new file mode 100644 index 0000000..864f5b0 --- /dev/null +++ b/Documentation/devicetree/bindings/sound/st,stm32-adfsdm.txt @@ -0,0 +1,63 @@ +STMicroelectronics Audio Digital Filter Sigma Delta modulators(DFSDM) + +The DFSDM allows PDM microphones capture through SPI interface. The Audio +interface is seems as a sub block of the DFSDM device. +For details on DFSDM bindings refer to ../iio/adc/st,stm32-dfsdm-adc.txt + +Required properties: + - compatible: "st,stm32h7-dfsdm-dai". + + - #sound-dai-cells : Must be equal to 0 + + - io-channels : phandle to iio dfsdm instance node. + +Example of a sound card using audio DFSDM node. + + sound_card { + compatible = "audio-graph-card"; + + dais = <&cpu_port>; + }; + + dfsdm: dfsdm@40017000 { + compatible = "st,stm32h7-dfsdm"; + reg = <0x40017000 0x400>; + clocks = <&rcc DFSDM1_CK>; + clock-names = "dfsdm"; + #interrupt-cells = <1>; + #address-cells = <1>; + #size-cells = <0>; + + dfsdm_adc0: filter@0 { + compatible = "st,stm32-dfsdm-dmic"; + reg = <0>; + interrupts = <110>; + dmas = <&dmamux1 101 0x400 0x00>; + dma-names = "rx"; + st,adc-channels = <1>; + st,adc-channel-names = "dmic0"; + st,adc-channel-types = "SPI_R"; + st,adc-channel-clk-src = "CLKOUT"; + st,filter-order = <5>; + + dfsdm_dai0: dfsdm-dai { + compatible = "st,stm32h7-dfsdm-dai"; + #sound-dai-cells = <0>; + io-channels = <&dfsdm_adc0 0>; + cpu_port: port { + dfsdm_endpoint: endpoint { + remote-endpoint = <&dmic0_endpoint>; + }; + }; + }; + }; + + dmic0: dmic@0 { + compatible = "dmic-codec"; + #sound-dai-cells = <0>; + port { + dmic0_endpoint: endpoint { + remote-endpoint = <&dfsdm_endpoint>; + }; + }; + };