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-rw-r--r--drivers/iio/adc/Kconfig46
-rw-r--r--drivers/iio/adc/Makefile4
-rw-r--r--drivers/iio/adc/ad7766.c330
-rw-r--r--drivers/iio/adc/at91_adc.c28
-rw-r--r--drivers/iio/adc/envelope-detector.c422
-rw-r--r--drivers/iio/adc/max1027.c17
-rw-r--r--drivers/iio/adc/stm32-adc-core.c303
-rw-r--r--drivers/iio/adc/stm32-adc-core.h52
-rw-r--r--drivers/iio/adc/stm32-adc.c518
-rw-r--r--drivers/iio/adc/ti-adc0832.c106
-rw-r--r--drivers/iio/adc/ti-adc161s626.c55
-rw-r--r--drivers/iio/adc/ti_am335x_adc.c148
12 files changed, 1983 insertions, 46 deletions
diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 99c051490eff..38bc319904c4 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -58,6 +58,18 @@ config AD7476
To compile this driver as a module, choose M here: the
module will be called ad7476.
+config AD7766
+ tristate "Analog Devices AD7766/AD7767 ADC driver"
+ depends on SPI_MASTER
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
+ help
+ Say yes here to build support for Analog Devices AD7766, AD7766-1,
+ AD7766-2, AD7767, AD7767-1, AD7767-2 SPI analog to digital converters.
+
+ To compile this driver as a module, choose M here: the module will be
+ called ad7766.
+
config AD7791
tristate "Analog Devices AD7791 ADC driver"
depends on SPI
@@ -195,6 +207,16 @@ config DA9150_GPADC
To compile this driver as a module, choose M here: the module will be
called berlin2-adc.
+config ENVELOPE_DETECTOR
+ tristate "Envelope detector using a DAC and a comparator"
+ depends on OF
+ help
+ Say yes here to build support for an envelope detector using a DAC
+ and a comparator.
+
+ To compile this driver as a module, choose M here: the module will be
+ called envelope-detector.
+
config EXYNOS_ADC
tristate "Exynos ADC driver support"
depends on ARCH_EXYNOS || ARCH_S3C24XX || ARCH_S3C64XX || (OF && COMPILE_TEST)
@@ -419,6 +441,28 @@ config ROCKCHIP_SARADC
To compile this driver as a module, choose M here: the
module will be called rockchip_saradc.
+config STM32_ADC_CORE
+ tristate "STMicroelectronics STM32 adc core"
+ depends on ARCH_STM32 || COMPILE_TEST
+ depends on OF
+ depends on REGULATOR
+ help
+ Select this option to enable the core driver for STMicroelectronics
+ STM32 analog-to-digital converter (ADC).
+
+ This driver can also be built as a module. If so, the module
+ will be called stm32-adc-core.
+
+config STM32_ADC
+ tristate "STMicroelectronics STM32 adc"
+ depends on STM32_ADC_CORE
+ help
+ Say yes here to build support for STMicroelectronics stm32 Analog
+ to Digital Converter (ADC).
+
+ This driver can also be built as a module. If so, the module
+ will be called stm32-adc.
+
config STX104
tristate "Apex Embedded Systems STX104 driver"
depends on X86 && ISA_BUS_API
@@ -449,6 +493,8 @@ config TI_ADC081C
config TI_ADC0832
tristate "Texas Instruments ADC0831/ADC0832/ADC0834/ADC0838"
depends on SPI
+ select IIO_BUFFER
+ select IIO_TRIGGERED_BUFFER
help
If you say yes here you get support for Texas Instruments ADC0831,
ADC0832, ADC0834, ADC0838 ADC chips.
diff --git a/drivers/iio/adc/Makefile b/drivers/iio/adc/Makefile
index 7a40c04c311f..d36c4be8d1fc 100644
--- a/drivers/iio/adc/Makefile
+++ b/drivers/iio/adc/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_AD7291) += ad7291.o
obj-$(CONFIG_AD7298) += ad7298.o
obj-$(CONFIG_AD7923) += ad7923.o
obj-$(CONFIG_AD7476) += ad7476.o
+obj-$(CONFIG_AD7766) += ad7766.o
obj-$(CONFIG_AD7791) += ad7791.o
obj-$(CONFIG_AD7793) += ad7793.o
obj-$(CONFIG_AD7887) += ad7887.o
@@ -20,6 +21,7 @@ obj-$(CONFIG_BCM_IPROC_ADC) += bcm_iproc_adc.o
obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
+obj-$(CONFIG_ENVELOPE_DETECTOR) += envelope-detector.o
obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
obj-$(CONFIG_HI8435) += hi8435.o
@@ -41,6 +43,8 @@ obj-$(CONFIG_QCOM_SPMI_IADC) += qcom-spmi-iadc.o
obj-$(CONFIG_QCOM_SPMI_VADC) += qcom-spmi-vadc.o
obj-$(CONFIG_ROCKCHIP_SARADC) += rockchip_saradc.o
obj-$(CONFIG_STX104) += stx104.o
+obj-$(CONFIG_STM32_ADC_CORE) += stm32-adc-core.o
+obj-$(CONFIG_STM32_ADC) += stm32-adc.o
obj-$(CONFIG_TI_ADC081C) += ti-adc081c.o
obj-$(CONFIG_TI_ADC0832) += ti-adc0832.o
obj-$(CONFIG_TI_ADC12138) += ti-adc12138.o
diff --git a/drivers/iio/adc/ad7766.c b/drivers/iio/adc/ad7766.c
new file mode 100644
index 000000000000..75cca42b6e70
--- /dev/null
+++ b/drivers/iio/adc/ad7766.c
@@ -0,0 +1,330 @@
+/*
+ * AD7766/AD7767 SPI ADC driver
+ *
+ * Copyright 2016 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/gpio/consumer.h>
+#include <linux/module.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/triggered_buffer.h>
+
+struct ad7766_chip_info {
+ unsigned int decimation_factor;
+};
+
+enum {
+ AD7766_SUPPLY_AVDD = 0,
+ AD7766_SUPPLY_DVDD = 1,
+ AD7766_SUPPLY_VREF = 2,
+ AD7766_NUM_SUPPLIES = 3
+};
+
+struct ad7766 {
+ const struct ad7766_chip_info *chip_info;
+ struct spi_device *spi;
+ struct clk *mclk;
+ struct gpio_desc *pd_gpio;
+ struct regulator_bulk_data reg[AD7766_NUM_SUPPLIES];
+
+ struct iio_trigger *trig;
+
+ struct spi_transfer xfer;
+ struct spi_message msg;
+
+ /*
+ * DMA (thus cache coherency maintenance) requires the
+ * transfer buffers to live in their own cache lines.
+ * Make the buffer large enough for one 24 bit sample and one 64 bit
+ * aligned 64 bit timestamp.
+ */
+ unsigned char data[ALIGN(3, sizeof(s64)) + sizeof(s64)]
+ ____cacheline_aligned;
+};
+
+/*
+ * AD7766 and AD7767 variations are interface compatible, the main difference is
+ * analog performance. Both parts will use the same ID.
+ */
+enum ad7766_device_ids {
+ ID_AD7766,
+ ID_AD7766_1,
+ ID_AD7766_2,
+};
+
+static irqreturn_t ad7766_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct ad7766 *ad7766 = iio_priv(indio_dev);
+ int ret;
+
+ ret = spi_sync(ad7766->spi, &ad7766->msg);
+ if (ret < 0)
+ goto done;
+
+ iio_push_to_buffers_with_timestamp(indio_dev, ad7766->data,
+ pf->timestamp);
+done:
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static int ad7766_preenable(struct iio_dev *indio_dev)
+{
+ struct ad7766 *ad7766 = iio_priv(indio_dev);
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(ad7766->reg), ad7766->reg);
+ if (ret < 0) {
+ dev_err(&ad7766->spi->dev, "Failed to enable supplies: %d\n",
+ ret);
+ return ret;
+ }
+
+ ret = clk_prepare_enable(ad7766->mclk);
+ if (ret < 0) {
+ dev_err(&ad7766->spi->dev, "Failed to enable MCLK: %d\n", ret);
+ regulator_bulk_disable(ARRAY_SIZE(ad7766->reg), ad7766->reg);
+ return ret;
+ }
+
+ if (ad7766->pd_gpio)
+ gpiod_set_value(ad7766->pd_gpio, 0);
+
+ return 0;
+}
+
+static int ad7766_postdisable(struct iio_dev *indio_dev)
+{
+ struct ad7766 *ad7766 = iio_priv(indio_dev);
+
+ if (ad7766->pd_gpio)
+ gpiod_set_value(ad7766->pd_gpio, 1);
+
+ /*
+ * The PD pin is synchronous to the clock, so give it some time to
+ * notice the change before we disable the clock.
+ */
+ msleep(20);
+
+ clk_disable_unprepare(ad7766->mclk);
+ regulator_bulk_disable(ARRAY_SIZE(ad7766->reg), ad7766->reg);
+
+ return 0;
+}
+
+static int ad7766_read_raw(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan, int *val, int *val2, long info)
+{
+ struct ad7766 *ad7766 = iio_priv(indio_dev);
+ struct regulator *vref = ad7766->reg[AD7766_SUPPLY_VREF].consumer;
+ int scale_uv;
+
+ switch (info) {
+ case IIO_CHAN_INFO_SCALE:
+ scale_uv = regulator_get_voltage(vref);
+ if (scale_uv < 0)
+ return scale_uv;
+ *val = scale_uv / 1000;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_SAMP_FREQ:
+ *val = clk_get_rate(ad7766->mclk) /
+ ad7766->chip_info->decimation_factor;
+ return IIO_VAL_INT;
+ }
+ return -EINVAL;
+}
+
+static const struct iio_chan_spec ad7766_channels[] = {
+ {
+ .type = IIO_VOLTAGE,
+ .indexed = 1,
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE),
+ .info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SAMP_FREQ),
+ .scan_type = {
+ .sign = 's',
+ .realbits = 24,
+ .storagebits = 32,
+ .endianness = IIO_BE,
+ },
+ },
+ IIO_CHAN_SOFT_TIMESTAMP(1),
+};
+
+static const struct ad7766_chip_info ad7766_chip_info[] = {
+ [ID_AD7766] = {
+ .decimation_factor = 8,
+ },
+ [ID_AD7766_1] = {
+ .decimation_factor = 16,
+ },
+ [ID_AD7766_2] = {
+ .decimation_factor = 32,
+ },
+};
+
+static const struct iio_buffer_setup_ops ad7766_buffer_setup_ops = {
+ .preenable = &ad7766_preenable,
+ .postenable = &iio_triggered_buffer_postenable,
+ .predisable = &iio_triggered_buffer_predisable,
+ .postdisable = &ad7766_postdisable,
+};
+
+static const struct iio_info ad7766_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = &ad7766_read_raw,
+};
+
+static irqreturn_t ad7766_irq(int irq, void *private)
+{
+ iio_trigger_poll(private);
+ return IRQ_HANDLED;
+}
+
+static int ad7766_set_trigger_state(struct iio_trigger *trig, bool enable)
+{
+ struct ad7766 *ad7766 = iio_trigger_get_drvdata(trig);
+
+ if (enable)
+ enable_irq(ad7766->spi->irq);
+ else
+ disable_irq(ad7766->spi->irq);
+
+ return 0;
+}
+
+static const struct iio_trigger_ops ad7766_trigger_ops = {
+ .owner = THIS_MODULE,
+ .set_trigger_state = ad7766_set_trigger_state,
+ .validate_device = iio_trigger_validate_own_device,
+};
+
+static int ad7766_probe(struct spi_device *spi)
+{
+ const struct spi_device_id *id = spi_get_device_id(spi);
+ struct iio_dev *indio_dev;
+ struct ad7766 *ad7766;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&spi->dev, sizeof(*ad7766));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ ad7766 = iio_priv(indio_dev);
+ ad7766->chip_info = &ad7766_chip_info[id->driver_data];
+
+ ad7766->mclk = devm_clk_get(&spi->dev, "mclk");
+ if (IS_ERR(ad7766->mclk))
+ return PTR_ERR(ad7766->mclk);
+
+ ad7766->reg[AD7766_SUPPLY_AVDD].supply = "avdd";
+ ad7766->reg[AD7766_SUPPLY_DVDD].supply = "dvdd";
+ ad7766->reg[AD7766_SUPPLY_VREF].supply = "vref";
+
+ ret = devm_regulator_bulk_get(&spi->dev, ARRAY_SIZE(ad7766->reg),
+ ad7766->reg);
+ if (ret)
+ return ret;
+
+ ad7766->pd_gpio = devm_gpiod_get_optional(&spi->dev, "powerdown",
+ GPIOD_OUT_HIGH);
+ if (IS_ERR(ad7766->pd_gpio))
+ return PTR_ERR(ad7766->pd_gpio);
+
+ indio_dev->dev.parent = &spi->dev;
+ indio_dev->name = spi_get_device_id(spi)->name;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+ indio_dev->channels = ad7766_channels;
+ indio_dev->num_channels = ARRAY_SIZE(ad7766_channels);
+ indio_dev->info = &ad7766_info;
+
+ if (spi->irq > 0) {
+ ad7766->trig = devm_iio_trigger_alloc(&spi->dev, "%s-dev%d",
+ indio_dev->name, indio_dev->id);
+ if (!ad7766->trig)
+ return -ENOMEM;
+
+ ad7766->trig->ops = &ad7766_trigger_ops;
+ ad7766->trig->dev.parent = &spi->dev;
+ iio_trigger_set_drvdata(ad7766->trig, ad7766);
+
+ ret = devm_request_irq(&spi->dev, spi->irq, ad7766_irq,
+ IRQF_TRIGGER_FALLING, dev_name(&spi->dev),
+ ad7766->trig);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * The device generates interrupts as long as it is powered up.
+ * Some platforms might not allow the option to power it down so
+ * disable the interrupt to avoid extra load on the system
+ */
+ disable_irq(spi->irq);
+
+ ret = devm_iio_trigger_register(&spi->dev, ad7766->trig);
+ if (ret)
+ return ret;
+ }
+
+ spi_set_drvdata(spi, indio_dev);
+
+ ad7766->spi = spi;
+
+ /* First byte always 0 */
+ ad7766->xfer.rx_buf = &ad7766->data[1];
+ ad7766->xfer.len = 3;
+
+ spi_message_init(&ad7766->msg);
+ spi_message_add_tail(&ad7766->xfer, &ad7766->msg);
+
+ ret = devm_iio_triggered_buffer_setup(&spi->dev, indio_dev,
+ &iio_pollfunc_store_time, &ad7766_trigger_handler,
+ &ad7766_buffer_setup_ops);
+ if (ret)
+ return ret;
+
+ ret = devm_iio_device_register(&spi->dev, indio_dev);
+ if (ret)
+ return ret;
+ return 0;
+}
+
+static const struct spi_device_id ad7766_id[] = {
+ {"ad7766", ID_AD7766},
+ {"ad7766-1", ID_AD7766_1},
+ {"ad7766-2", ID_AD7766_2},
+ {"ad7767", ID_AD7766},
+ {"ad7767-1", ID_AD7766_1},
+ {"ad7767-2", ID_AD7766_2},
+ {}
+};
+MODULE_DEVICE_TABLE(spi, ad7766_id);
+
+static struct spi_driver ad7766_driver = {
+ .driver = {
+ .name = "ad7766",
+ },
+ .probe = ad7766_probe,
+ .id_table = ad7766_id,
+};
+module_spi_driver(ad7766_driver);
+
+MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
+MODULE_DESCRIPTION("Analog Devices AD7766 and AD7767 ADCs driver support");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/at91_adc.c b/drivers/iio/adc/at91_adc.c
index bbdac07f4aaa..34b928cefeed 100644
--- a/drivers/iio/adc/at91_adc.c
+++ b/drivers/iio/adc/at91_adc.c
@@ -30,6 +30,7 @@
#include <linux/iio/trigger.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
+#include <linux/pinctrl/consumer.h>
/* Registers */
#define AT91_ADC_CR 0x00 /* Control Register */
@@ -1347,6 +1348,32 @@ static int at91_adc_remove(struct platform_device *pdev)
return 0;
}
+#ifdef CONFIG_PM_SLEEP
+static int at91_adc_suspend(struct device *dev)
+{
+ struct iio_dev *idev = platform_get_drvdata(to_platform_device(dev));
+ struct at91_adc_state *st = iio_priv(idev);
+
+ pinctrl_pm_select_sleep_state(dev);
+ clk_disable_unprepare(st->clk);
+
+ return 0;
+}
+
+static int at91_adc_resume(struct device *dev)
+{
+ struct iio_dev *idev = platform_get_drvdata(to_platform_device(dev));
+ struct at91_adc_state *st = iio_priv(idev);
+
+ clk_prepare_enable(st->clk);
+ pinctrl_pm_select_default_state(dev);
+
+ return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(at91_adc_pm_ops, at91_adc_suspend, at91_adc_resume);
+
static struct at91_adc_caps at91sam9260_caps = {
.calc_startup_ticks = calc_startup_ticks_9260,
.num_channels = 4,
@@ -1441,6 +1468,7 @@ static struct platform_driver at91_adc_driver = {
.driver = {
.name = DRIVER_NAME,
.of_match_table = of_match_ptr(at91_adc_dt_ids),
+ .pm = &at91_adc_pm_ops,
},
};
diff --git a/drivers/iio/adc/envelope-detector.c b/drivers/iio/adc/envelope-detector.c
new file mode 100644
index 000000000000..fef15c0d7c9c
--- /dev/null
+++ b/drivers/iio/adc/envelope-detector.c
@@ -0,0 +1,422 @@
+/*
+ * Driver for an envelope detector using a DAC and a comparator
+ *
+ * Copyright (C) 2016 Axentia Technologies AB
+ *
+ * Author: Peter Rosin <peda@axentia.se>
+ *
+ * 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.
+ */
+
+/*
+ * The DAC is used to find the peak level of an alternating voltage input
+ * signal by a binary search using the output of a comparator wired to
+ * an interrupt pin. Like so:
+ * _
+ * | \
+ * input +------>-------|+ \
+ * | \
+ * .-------. | }---.
+ * | | | / |
+ * | dac|-->--|- / |
+ * | | |_/ |
+ * | | |
+ * | | |
+ * | irq|------<-------'
+ * | |
+ * '-------'
+ */
+
+#include <linux/completion.h>
+#include <linux/device.h>
+#include <linux/err.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/iio/consumer.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/workqueue.h>
+
+struct envelope {
+ spinlock_t comp_lock; /* protects comp */
+ int comp;
+
+ struct mutex read_lock; /* protects everything else */
+
+ int comp_irq;
+ u32 comp_irq_trigger;
+ u32 comp_irq_trigger_inv;
+
+ struct iio_channel *dac;
+ struct delayed_work comp_timeout;
+
+ unsigned int comp_interval;
+ bool invert;
+ u32 dac_max;
+
+ int high;
+ int level;
+ int low;
+
+ struct completion done;
+};
+
+/*
+ * The envelope_detector_comp_latch function works together with the compare
+ * interrupt service routine below (envelope_detector_comp_isr) as a latch
+ * (one-bit memory) for if the interrupt has triggered since last calling
+ * this function.
+ * The ..._comp_isr function disables the interrupt so that the cpu does not
+ * need to service a possible interrupt flood from the comparator when no-one
+ * cares anyway, and this ..._comp_latch function reenables them again if
+ * needed.
+ */
+static int envelope_detector_comp_latch(struct envelope *env)
+{
+ int comp;
+
+ spin_lock_irq(&env->comp_lock);
+ comp = env->comp;
+ env->comp = 0;
+ spin_unlock_irq(&env->comp_lock);
+
+ if (!comp)
+ return 0;
+
+ /*
+ * The irq was disabled, and is reenabled just now.
+ * But there might have been a pending irq that
+ * happened while the irq was disabled that fires
+ * just as the irq is reenabled. That is not what
+ * is desired.
+ */
+ enable_irq(env->comp_irq);
+
+ /* So, synchronize this possibly pending irq... */
+ synchronize_irq(env->comp_irq);
+
+ /* ...and redo the whole dance. */
+ spin_lock_irq(&env->comp_lock);
+ comp = env->comp;
+ env->comp = 0;
+ spin_unlock_irq(&env->comp_lock);
+
+ if (comp)
+ enable_irq(env->comp_irq);
+
+ return 1;
+}
+
+static irqreturn_t envelope_detector_comp_isr(int irq, void *ctx)
+{
+ struct envelope *env = ctx;
+
+ spin_lock(&env->comp_lock);
+ env->comp = 1;
+ disable_irq_nosync(env->comp_irq);
+ spin_unlock(&env->comp_lock);
+
+ return IRQ_HANDLED;
+}
+
+static void envelope_detector_setup_compare(struct envelope *env)
+{
+ int ret;
+
+ /*
+ * Do a binary search for the peak input level, and stop
+ * when that level is "trapped" between two adjacent DAC
+ * values.
+ * When invert is active, use the midpoint floor so that
+ * env->level ends up as env->low when the termination
+ * criteria below is fulfilled, and use the midpoint
+ * ceiling when invert is not active so that env->level
+ * ends up as env->high in that case.
+ */
+ env->level = (env->high + env->low + !env->invert) / 2;
+
+ if (env->high == env->low + 1) {
+ complete(&env->done);
+ return;
+ }
+
+ /* Set a "safe" DAC level (if there is such a thing)... */
+ ret = iio_write_channel_raw(env->dac, env->invert ? 0 : env->dac_max);
+ if (ret < 0)
+ goto err;
+
+ /* ...clear the comparison result... */
+ envelope_detector_comp_latch(env);
+
+ /* ...set the real DAC level... */
+ ret = iio_write_channel_raw(env->dac, env->level);
+ if (ret < 0)
+ goto err;
+
+ /* ...and wait for a bit to see if the latch catches anything. */
+ schedule_delayed_work(&env->comp_timeout,
+ msecs_to_jiffies(env->comp_interval));
+ return;
+
+err:
+ env->level = ret;
+ complete(&env->done);
+}
+
+static void envelope_detector_timeout(struct work_struct *work)
+{
+ struct envelope *env = container_of(work, struct envelope,
+ comp_timeout.work);
+
+ /* Adjust low/high depending on the latch content... */
+ if (!envelope_detector_comp_latch(env) ^ !env->invert)
+ env->low = env->level;
+ else
+ env->high = env->level;
+
+ /* ...and continue the search. */
+ envelope_detector_setup_compare(env);
+}
+
+static int envelope_detector_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct envelope *env = iio_priv(indio_dev);
+ int ret;
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ /*
+ * When invert is active, start with high=max+1 and low=0
+ * since we will end up with the low value when the
+ * termination criteria is fulfilled (rounding down). And
+ * start with high=max and low=-1 when invert is not active
+ * since we will end up with the high value in that case.
+ * This ensures that the returned value in both cases are
+ * in the same range as the DAC and is a value that has not
+ * triggered the comparator.
+ */
+ mutex_lock(&env->read_lock);
+ env->high = env->dac_max + env->invert;
+ env->low = -1 + env->invert;
+ envelope_detector_setup_compare(env);
+ wait_for_completion(&env->done);
+ if (env->level < 0) {
+ ret = env->level;
+ goto err_unlock;
+ }
+ *val = env->invert ? env->dac_max - env->level : env->level;
+ mutex_unlock(&env->read_lock);
+
+ return IIO_VAL_INT;
+
+ case IIO_CHAN_INFO_SCALE:
+ return iio_read_channel_scale(env->dac, val, val2);
+ }
+
+ return -EINVAL;
+
+err_unlock:
+ mutex_unlock(&env->read_lock);
+ return ret;
+}
+
+static ssize_t envelope_show_invert(struct iio_dev *indio_dev,
+ uintptr_t private,
+ struct iio_chan_spec const *ch, char *buf)
+{
+ struct envelope *env = iio_priv(indio_dev);
+
+ return sprintf(buf, "%u\n", env->invert);
+}
+
+static ssize_t envelope_store_invert(struct iio_dev *indio_dev,
+ uintptr_t private,
+ struct iio_chan_spec const *ch,
+ const char *buf, size_t len)
+{
+ struct envelope *env = iio_priv(indio_dev);
+ unsigned long invert;
+ int ret;
+ u32 trigger;
+
+ ret = kstrtoul(buf, 0, &invert);
+ if (ret < 0)
+ return ret;
+ if (invert > 1)
+ return -EINVAL;
+
+ trigger = invert ? env->comp_irq_trigger_inv : env->comp_irq_trigger;
+
+ mutex_lock(&env->read_lock);
+ if (invert != env->invert)
+ ret = irq_set_irq_type(env->comp_irq, trigger);
+ if (!ret) {
+ env->invert = invert;
+ ret = len;
+ }
+ mutex_unlock(&env->read_lock);
+
+ return ret;
+}
+
+static ssize_t envelope_show_comp_interval(struct iio_dev *indio_dev,
+ uintptr_t private,
+ struct iio_chan_spec const *ch,
+ char *buf)
+{
+ struct envelope *env = iio_priv(indio_dev);
+
+ return sprintf(buf, "%u\n", env->comp_interval);
+}
+
+static ssize_t envelope_store_comp_interval(struct iio_dev *indio_dev,
+ uintptr_t private,
+ struct iio_chan_spec const *ch,
+ const char *buf, size_t len)
+{
+ struct envelope *env = iio_priv(indio_dev);
+ unsigned long interval;
+ int ret;
+
+ ret = kstrtoul(buf, 0, &interval);
+ if (ret < 0)
+ return ret;
+ if (interval > 1000)
+ return -EINVAL;
+
+ mutex_lock(&env->read_lock);
+ env->comp_interval = interval;
+ mutex_unlock(&env->read_lock);
+
+ return len;
+}
+
+static const struct iio_chan_spec_ext_info envelope_detector_ext_info[] = {
+ { .name = "invert",
+ .read = envelope_show_invert,
+ .write = envelope_store_invert, },
+ { .name = "compare_interval",
+ .read = envelope_show_comp_interval,
+ .write = envelope_store_comp_interval, },
+ { /* sentinel */ }
+};
+
+static const struct iio_chan_spec envelope_detector_iio_channel = {
+ .type = IIO_ALTVOLTAGE,
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW)
+ | BIT(IIO_CHAN_INFO_SCALE),
+ .ext_info = envelope_detector_ext_info,
+ .indexed = 1,
+};
+
+static const struct iio_info envelope_detector_info = {
+ .read_raw = &envelope_detector_read_raw,
+ .driver_module = THIS_MODULE,
+};
+
+static int envelope_detector_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct iio_dev *indio_dev;
+ struct envelope *env;
+ enum iio_chan_type type;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(dev, sizeof(*env));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, indio_dev);
+ env = iio_priv(indio_dev);
+ env->comp_interval = 50; /* some sensible default? */
+
+ spin_lock_init(&env->comp_lock);
+ mutex_init(&env->read_lock);
+ init_completion(&env->done);
+ INIT_DELAYED_WORK(&env->comp_timeout, envelope_detector_timeout);
+
+ indio_dev->name = dev_name(dev);
+ indio_dev->dev.parent = dev;
+ indio_dev->dev.of_node = dev->of_node;
+ indio_dev->info = &envelope_detector_info;
+ indio_dev->channels = &envelope_detector_iio_channel;
+ indio_dev->num_channels = 1;
+
+ env->dac = devm_iio_channel_get(dev, "dac");
+ if (IS_ERR(env->dac)) {
+ if (PTR_ERR(env->dac) != -EPROBE_DEFER)
+ dev_err(dev, "failed to get dac input channel\n");
+ return PTR_ERR(env->dac);
+ }
+
+ env->comp_irq = platform_get_irq_byname(pdev, "comp");
+ if (env->comp_irq < 0) {
+ if (env->comp_irq != -EPROBE_DEFER)
+ dev_err(dev, "failed to get compare interrupt\n");
+ return env->comp_irq;
+ }
+
+ ret = devm_request_irq(dev, env->comp_irq, envelope_detector_comp_isr,
+ 0, "envelope-detector", env);
+ if (ret) {
+ if (ret != -EPROBE_DEFER)
+ dev_err(dev, "failed to request interrupt\n");
+ return ret;
+ }
+ env->comp_irq_trigger = irq_get_trigger_type(env->comp_irq);
+ if (env->comp_irq_trigger & IRQF_TRIGGER_RISING)
+ env->comp_irq_trigger_inv |= IRQF_TRIGGER_FALLING;
+ if (env->comp_irq_trigger & IRQF_TRIGGER_FALLING)
+ env->comp_irq_trigger_inv |= IRQF_TRIGGER_RISING;
+ if (env->comp_irq_trigger & IRQF_TRIGGER_HIGH)
+ env->comp_irq_trigger_inv |= IRQF_TRIGGER_LOW;
+ if (env->comp_irq_trigger & IRQF_TRIGGER_LOW)
+ env->comp_irq_trigger_inv |= IRQF_TRIGGER_HIGH;
+
+ ret = iio_get_channel_type(env->dac, &type);
+ if (ret < 0)
+ return ret;
+
+ if (type != IIO_VOLTAGE) {
+ dev_err(dev, "dac is of the wrong type\n");
+ return -EINVAL;
+ }
+
+ ret = iio_read_max_channel_raw(env->dac, &env->dac_max);
+ if (ret < 0) {
+ dev_err(dev, "dac does not indicate its raw maximum value\n");
+ return ret;
+ }
+
+ return devm_iio_device_register(dev, indio_dev);
+}
+
+static const struct of_device_id envelope_detector_match[] = {
+ { .compatible = "axentia,tse850-envelope-detector", },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, envelope_detector_match);
+
+static struct platform_driver envelope_detector_driver = {
+ .probe = envelope_detector_probe,
+ .driver = {
+ .name = "iio-envelope-detector",
+ .of_match_table = envelope_detector_match,
+ },
+};
+module_platform_driver(envelope_detector_driver);
+
+MODULE_DESCRIPTION("Envelope detector using a DAC and a comparator");
+MODULE_AUTHOR("Peter Rosin <peda@axentia.se>");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/iio/adc/max1027.c b/drivers/iio/adc/max1027.c
index 712fbd2b1f16..3b7c4f78f37a 100644
--- a/drivers/iio/adc/max1027.c
+++ b/drivers/iio/adc/max1027.c
@@ -238,7 +238,9 @@ static int max1027_read_single_value(struct iio_dev *indio_dev,
/* Configure conversion register with the requested chan */
st->reg = MAX1027_CONV_REG | MAX1027_CHAN(chan->channel) |
- MAX1027_NOSCAN | !!(chan->type == IIO_TEMP);
+ MAX1027_NOSCAN;
+ if (chan->type == IIO_TEMP)
+ st->reg |= MAX1027_TEMP;
ret = spi_write(st->spi, &st->reg, 1);
if (ret < 0) {
dev_err(&indio_dev->dev,
@@ -360,17 +362,6 @@ static int max1027_set_trigger_state(struct iio_trigger *trig, bool state)
return 0;
}
-static int max1027_validate_device(struct iio_trigger *trig,
- struct iio_dev *indio_dev)
-{
- struct iio_dev *indio = iio_trigger_get_drvdata(trig);
-
- if (indio != indio_dev)
- return -EINVAL;
-
- return 0;
-}
-
static irqreturn_t max1027_trigger_handler(int irq, void *private)
{
struct iio_poll_func *pf = (struct iio_poll_func *)private;
@@ -391,7 +382,7 @@ static irqreturn_t max1027_trigger_handler(int irq, void *private)
static const struct iio_trigger_ops max1027_trigger_ops = {
.owner = THIS_MODULE,
- .validate_device = &max1027_validate_device,
+ .validate_device = &iio_trigger_validate_own_device,
.set_trigger_state = &max1027_set_trigger_state,
};
diff --git a/drivers/iio/adc/stm32-adc-core.c b/drivers/iio/adc/stm32-adc-core.c
new file mode 100644
index 000000000000..4214b0cd6b1b
--- /dev/null
+++ b/drivers/iio/adc/stm32-adc-core.c
@@ -0,0 +1,303 @@
+/*
+ * This file is part of STM32 ADC driver
+ *
+ * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
+ * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
+ *
+ * Inspired from: fsl-imx25-tsadc
+ *
+ * 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/clk.h>
+#include <linux/interrupt.h>
+#include <linux/irqchip/chained_irq.h>
+#include <linux/irqdesc.h>
+#include <linux/irqdomain.h>
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/regulator/consumer.h>
+#include <linux/slab.h>
+
+#include "stm32-adc-core.h"
+
+/* STM32F4 - common registers for all ADC instances: 1, 2 & 3 */
+#define STM32F4_ADC_CSR (STM32_ADCX_COMN_OFFSET + 0x00)
+#define STM32F4_ADC_CCR (STM32_ADCX_COMN_OFFSET + 0x04)
+
+/* STM32F4_ADC_CSR - bit fields */
+#define STM32F4_EOC3 BIT(17)
+#define STM32F4_EOC2 BIT(9)
+#define STM32F4_EOC1 BIT(1)
+
+/* STM32F4_ADC_CCR - bit fields */
+#define STM32F4_ADC_ADCPRE_SHIFT 16
+#define STM32F4_ADC_ADCPRE_MASK GENMASK(17, 16)
+
+/* STM32 F4 maximum analog clock rate (from datasheet) */
+#define STM32F4_ADC_MAX_CLK_RATE 36000000
+
+/**
+ * struct stm32_adc_priv - stm32 ADC core private data
+ * @irq: irq for ADC block
+ * @domain: irq domain reference
+ * @aclk: clock reference for the analog circuitry
+ * @vref: regulator reference
+ * @common: common data for all ADC instances
+ */
+struct stm32_adc_priv {
+ int irq;
+ struct irq_domain *domain;
+ struct clk *aclk;
+ struct regulator *vref;
+ struct stm32_adc_common common;
+};
+
+static struct stm32_adc_priv *to_stm32_adc_priv(struct stm32_adc_common *com)
+{
+ return container_of(com, struct stm32_adc_priv, common);
+}
+
+/* STM32F4 ADC internal common clock prescaler division ratios */
+static int stm32f4_pclk_div[] = {2, 4, 6, 8};
+
+/**
+ * stm32f4_adc_clk_sel() - Select stm32f4 ADC common clock prescaler
+ * @priv: stm32 ADC core private data
+ * Select clock prescaler used for analog conversions, before using ADC.
+ */
+static int stm32f4_adc_clk_sel(struct platform_device *pdev,
+ struct stm32_adc_priv *priv)
+{
+ unsigned long rate;
+ u32 val;
+ int i;
+
+ rate = clk_get_rate(priv->aclk);
+ for (i = 0; i < ARRAY_SIZE(stm32f4_pclk_div); i++) {
+ if ((rate / stm32f4_pclk_div[i]) <= STM32F4_ADC_MAX_CLK_RATE)
+ break;
+ }
+ if (i >= ARRAY_SIZE(stm32f4_pclk_div))
+ return -EINVAL;
+
+ val = readl_relaxed(priv->common.base + STM32F4_ADC_CCR);
+ val &= ~STM32F4_ADC_ADCPRE_MASK;
+ val |= i << STM32F4_ADC_ADCPRE_SHIFT;
+ writel_relaxed(val, priv->common.base + STM32F4_ADC_CCR);
+
+ dev_dbg(&pdev->dev, "Using analog clock source at %ld kHz\n",
+ rate / (stm32f4_pclk_div[i] * 1000));
+
+ return 0;
+}
+
+/* ADC common interrupt for all instances */
+static void stm32_adc_irq_handler(struct irq_desc *desc)
+{
+ struct stm32_adc_priv *priv = irq_desc_get_handler_data(desc);
+ struct irq_chip *chip = irq_desc_get_chip(desc);
+ u32 status;
+
+ chained_irq_enter(chip, desc);
+ status = readl_relaxed(priv->common.base + STM32F4_ADC_CSR);
+
+ if (status & STM32F4_EOC1)
+ generic_handle_irq(irq_find_mapping(priv->domain, 0));
+
+ if (status & STM32F4_EOC2)
+ generic_handle_irq(irq_find_mapping(priv->domain, 1));
+
+ if (status & STM32F4_EOC3)
+ generic_handle_irq(irq_find_mapping(priv->domain, 2));
+
+ chained_irq_exit(chip, desc);
+};
+
+static int stm32_adc_domain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hwirq)
+{
+ irq_set_chip_data(irq, d->host_data);
+ irq_set_chip_and_handler(irq, &dummy_irq_chip, handle_level_irq);
+
+ return 0;
+}
+
+static void stm32_adc_domain_unmap(struct irq_domain *d, unsigned int irq)
+{
+ irq_set_chip_and_handler(irq, NULL, NULL);
+ irq_set_chip_data(irq, NULL);
+}
+
+static const struct irq_domain_ops stm32_adc_domain_ops = {
+ .map = stm32_adc_domain_map,
+ .unmap = stm32_adc_domain_unmap,
+ .xlate = irq_domain_xlate_onecell,
+};
+
+static int stm32_adc_irq_probe(struct platform_device *pdev,
+ struct stm32_adc_priv *priv)
+{
+ struct device_node *np = pdev->dev.of_node;
+
+ priv->irq = platform_get_irq(pdev, 0);
+ if (priv->irq < 0) {
+ dev_err(&pdev->dev, "failed to get irq\n");
+ return priv->irq;
+ }
+
+ priv->domain = irq_domain_add_simple(np, STM32_ADC_MAX_ADCS, 0,
+ &stm32_adc_domain_ops,
+ priv);
+ if (!priv->domain) {
+ dev_err(&pdev->dev, "Failed to add irq domain\n");
+ return -ENOMEM;
+ }
+
+ irq_set_chained_handler(priv->irq, stm32_adc_irq_handler);
+ irq_set_handler_data(priv->irq, priv);
+
+ return 0;
+}
+
+static void stm32_adc_irq_remove(struct platform_device *pdev,
+ struct stm32_adc_priv *priv)
+{
+ int hwirq;
+
+ for (hwirq = 0; hwirq < STM32_ADC_MAX_ADCS; hwirq++)
+ irq_dispose_mapping(irq_find_mapping(priv->domain, hwirq));
+ irq_domain_remove(priv->domain);
+ irq_set_chained_handler(priv->irq, NULL);
+}
+
+static int stm32_adc_probe(struct platform_device *pdev)
+{
+ struct stm32_adc_priv *priv;
+ struct device_node *np = pdev->dev.of_node;
+ struct resource *res;
+ int ret;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ priv->common.base = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(priv->common.base))
+ return PTR_ERR(priv->common.base);
+
+ priv->vref = devm_regulator_get(&pdev->dev, "vref");
+ if (IS_ERR(priv->vref)) {
+ ret = PTR_ERR(priv->vref);
+ dev_err(&pdev->dev, "vref get failed, %d\n", ret);
+ return ret;
+ }
+
+ ret = regulator_enable(priv->vref);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "vref enable failed\n");
+ return ret;
+ }
+
+ ret = regulator_get_voltage(priv->vref);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "vref get voltage failed, %d\n", ret);
+ goto err_regulator_disable;
+ }
+ priv->common.vref_mv = ret / 1000;
+ dev_dbg(&pdev->dev, "vref+=%dmV\n", priv->common.vref_mv);
+
+ priv->aclk = devm_clk_get(&pdev->dev, "adc");
+ if (IS_ERR(priv->aclk)) {
+ ret = PTR_ERR(priv->aclk);
+ dev_err(&pdev->dev, "Can't get 'adc' clock\n");
+ goto err_regulator_disable;
+ }
+
+ ret = clk_prepare_enable(priv->aclk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "adc clk enable failed\n");
+ goto err_regulator_disable;
+ }
+
+ ret = stm32f4_adc_clk_sel(pdev, priv);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "adc clk selection failed\n");
+ goto err_clk_disable;
+ }
+
+ ret = stm32_adc_irq_probe(pdev, priv);
+ if (ret < 0)
+ goto err_clk_disable;
+
+ platform_set_drvdata(pdev, &priv->common);
+
+ ret = of_platform_populate(np, NULL, NULL, &pdev->dev);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "failed to populate DT children\n");
+ goto err_irq_remove;
+ }
+
+ return 0;
+
+err_irq_remove:
+ stm32_adc_irq_remove(pdev, priv);
+
+err_clk_disable:
+ clk_disable_unprepare(priv->aclk);
+
+err_regulator_disable:
+ regulator_disable(priv->vref);
+
+ return ret;
+}
+
+static int stm32_adc_remove(struct platform_device *pdev)
+{
+ struct stm32_adc_common *common = platform_get_drvdata(pdev);
+ struct stm32_adc_priv *priv = to_stm32_adc_priv(common);
+
+ of_platform_depopulate(&pdev->dev);
+ stm32_adc_irq_remove(pdev, priv);
+ clk_disable_unprepare(priv->aclk);
+ regulator_disable(priv->vref);
+
+ return 0;
+}
+
+static const struct of_device_id stm32_adc_of_match[] = {
+ { .compatible = "st,stm32f4-adc-core" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
+
+static struct platform_driver stm32_adc_driver = {
+ .probe = stm32_adc_probe,
+ .remove = stm32_adc_remove,
+ .driver = {
+ .name = "stm32-adc-core",
+ .of_match_table = stm32_adc_of_match,
+ },
+};
+module_platform_driver(stm32_adc_driver);
+
+MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 ADC core driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:stm32-adc-core");
diff --git a/drivers/iio/adc/stm32-adc-core.h b/drivers/iio/adc/stm32-adc-core.h
new file mode 100644
index 000000000000..081fa5f55015
--- /dev/null
+++ b/drivers/iio/adc/stm32-adc-core.h
@@ -0,0 +1,52 @@
+/*
+ * This file is part of STM32 ADC driver
+ *
+ * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
+ * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
+ *
+ * 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/>.
+ */
+
+#ifndef __STM32_ADC_H
+#define __STM32_ADC_H
+
+/*
+ * STM32 - ADC global register map
+ * ________________________________________________________
+ * | Offset | Register |
+ * --------------------------------------------------------
+ * | 0x000 | Master ADC1 |
+ * --------------------------------------------------------
+ * | 0x100 | Slave ADC2 |
+ * --------------------------------------------------------
+ * | 0x200 | Slave ADC3 |
+ * --------------------------------------------------------
+ * | 0x300 | Master & Slave common regs |
+ * --------------------------------------------------------
+ */
+#define STM32_ADC_MAX_ADCS 3
+#define STM32_ADCX_COMN_OFFSET 0x300
+
+/**
+ * struct stm32_adc_common - stm32 ADC driver common data (for all instances)
+ * @base: control registers base cpu addr
+ * @vref_mv: vref voltage (mv)
+ */
+struct stm32_adc_common {
+ void __iomem *base;
+ int vref_mv;
+};
+
+#endif
diff --git a/drivers/iio/adc/stm32-adc.c b/drivers/iio/adc/stm32-adc.c
new file mode 100644
index 000000000000..5715e79f4935
--- /dev/null
+++ b/drivers/iio/adc/stm32-adc.c
@@ -0,0 +1,518 @@
+/*
+ * This file is part of STM32 ADC driver
+ *
+ * Copyright (C) 2016, STMicroelectronics - All Rights Reserved
+ * Author: Fabrice Gasnier <fabrice.gasnier@st.com>.
+ *
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/iio/iio.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/of.h>
+
+#include "stm32-adc-core.h"
+
+/* STM32F4 - Registers for each ADC instance */
+#define STM32F4_ADC_SR 0x00
+#define STM32F4_ADC_CR1 0x04
+#define STM32F4_ADC_CR2 0x08
+#define STM32F4_ADC_SMPR1 0x0C
+#define STM32F4_ADC_SMPR2 0x10
+#define STM32F4_ADC_HTR 0x24
+#define STM32F4_ADC_LTR 0x28
+#define STM32F4_ADC_SQR1 0x2C
+#define STM32F4_ADC_SQR2 0x30
+#define STM32F4_ADC_SQR3 0x34
+#define STM32F4_ADC_JSQR 0x38
+#define STM32F4_ADC_JDR1 0x3C
+#define STM32F4_ADC_JDR2 0x40
+#define STM32F4_ADC_JDR3 0x44
+#define STM32F4_ADC_JDR4 0x48
+#define STM32F4_ADC_DR 0x4C
+
+/* STM32F4_ADC_SR - bit fields */
+#define STM32F4_STRT BIT(4)
+#define STM32F4_EOC BIT(1)
+
+/* STM32F4_ADC_CR1 - bit fields */
+#define STM32F4_SCAN BIT(8)
+#define STM32F4_EOCIE BIT(5)
+
+/* STM32F4_ADC_CR2 - bit fields */
+#define STM32F4_SWSTART BIT(30)
+#define STM32F4_EXTEN_MASK GENMASK(29, 28)
+#define STM32F4_EOCS BIT(10)
+#define STM32F4_ADON BIT(0)
+
+/* STM32F4_ADC_SQR1 - bit fields */
+#define STM32F4_L_SHIFT 20
+#define STM32F4_L_MASK GENMASK(23, 20)
+
+/* STM32F4_ADC_SQR3 - bit fields */
+#define STM32F4_SQ1_SHIFT 0
+#define STM32F4_SQ1_MASK GENMASK(4, 0)
+
+#define STM32_ADC_TIMEOUT_US 100000
+#define STM32_ADC_TIMEOUT (msecs_to_jiffies(STM32_ADC_TIMEOUT_US / 1000))
+
+/**
+ * struct stm32_adc - private data of each ADC IIO instance
+ * @common: reference to ADC block common data
+ * @offset: ADC instance register offset in ADC block
+ * @completion: end of single conversion completion
+ * @buffer: data buffer
+ * @clk: clock for this adc instance
+ * @irq: interrupt for this adc instance
+ * @lock: spinlock
+ */
+struct stm32_adc {
+ struct stm32_adc_common *common;
+ u32 offset;
+ struct completion completion;
+ u16 *buffer;
+ struct clk *clk;
+ int irq;
+ spinlock_t lock; /* interrupt lock */
+};
+
+/**
+ * struct stm32_adc_chan_spec - specification of stm32 adc channel
+ * @type: IIO channel type
+ * @channel: channel number (single ended)
+ * @name: channel name (single ended)
+ */
+struct stm32_adc_chan_spec {
+ enum iio_chan_type type;
+ int channel;
+ const char *name;
+};
+
+/* Input definitions common for all STM32F4 instances */
+static const struct stm32_adc_chan_spec stm32f4_adc123_channels[] = {
+ { IIO_VOLTAGE, 0, "in0" },
+ { IIO_VOLTAGE, 1, "in1" },
+ { IIO_VOLTAGE, 2, "in2" },
+ { IIO_VOLTAGE, 3, "in3" },
+ { IIO_VOLTAGE, 4, "in4" },
+ { IIO_VOLTAGE, 5, "in5" },
+ { IIO_VOLTAGE, 6, "in6" },
+ { IIO_VOLTAGE, 7, "in7" },
+ { IIO_VOLTAGE, 8, "in8" },
+ { IIO_VOLTAGE, 9, "in9" },
+ { IIO_VOLTAGE, 10, "in10" },
+ { IIO_VOLTAGE, 11, "in11" },
+ { IIO_VOLTAGE, 12, "in12" },
+ { IIO_VOLTAGE, 13, "in13" },
+ { IIO_VOLTAGE, 14, "in14" },
+ { IIO_VOLTAGE, 15, "in15" },
+};
+
+/**
+ * STM32 ADC registers access routines
+ * @adc: stm32 adc instance
+ * @reg: reg offset in adc instance
+ *
+ * Note: All instances share same base, with 0x0, 0x100 or 0x200 offset resp.
+ * for adc1, adc2 and adc3.
+ */
+static u32 stm32_adc_readl(struct stm32_adc *adc, u32 reg)
+{
+ return readl_relaxed(adc->common->base + adc->offset + reg);
+}
+
+static u16 stm32_adc_readw(struct stm32_adc *adc, u32 reg)
+{
+ return readw_relaxed(adc->common->base + adc->offset + reg);
+}
+
+static void stm32_adc_writel(struct stm32_adc *adc, u32 reg, u32 val)
+{
+ writel_relaxed(val, adc->common->base + adc->offset + reg);
+}
+
+static void stm32_adc_set_bits(struct stm32_adc *adc, u32 reg, u32 bits)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&adc->lock, flags);
+ stm32_adc_writel(adc, reg, stm32_adc_readl(adc, reg) | bits);
+ spin_unlock_irqrestore(&adc->lock, flags);
+}
+
+static void stm32_adc_clr_bits(struct stm32_adc *adc, u32 reg, u32 bits)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(&adc->lock, flags);
+ stm32_adc_writel(adc, reg, stm32_adc_readl(adc, reg) & ~bits);
+ spin_unlock_irqrestore(&adc->lock, flags);
+}
+
+/**
+ * stm32_adc_conv_irq_enable() - Enable end of conversion interrupt
+ * @adc: stm32 adc instance
+ */
+static void stm32_adc_conv_irq_enable(struct stm32_adc *adc)
+{
+ stm32_adc_set_bits(adc, STM32F4_ADC_CR1, STM32F4_EOCIE);
+};
+
+/**
+ * stm32_adc_conv_irq_disable() - Disable end of conversion interrupt
+ * @adc: stm32 adc instance
+ */
+static void stm32_adc_conv_irq_disable(struct stm32_adc *adc)
+{
+ stm32_adc_clr_bits(adc, STM32F4_ADC_CR1, STM32F4_EOCIE);
+}
+
+/**
+ * stm32_adc_start_conv() - Start conversions for regular channels.
+ * @adc: stm32 adc instance
+ */
+static void stm32_adc_start_conv(struct stm32_adc *adc)
+{
+ stm32_adc_set_bits(adc, STM32F4_ADC_CR1, STM32F4_SCAN);
+ stm32_adc_set_bits(adc, STM32F4_ADC_CR2, STM32F4_EOCS | STM32F4_ADON);
+
+ /* Wait for Power-up time (tSTAB from datasheet) */
+ usleep_range(2, 3);
+
+ /* Software start ? (e.g. trigger detection disabled ?) */
+ if (!(stm32_adc_readl(adc, STM32F4_ADC_CR2) & STM32F4_EXTEN_MASK))
+ stm32_adc_set_bits(adc, STM32F4_ADC_CR2, STM32F4_SWSTART);
+}
+
+static void stm32_adc_stop_conv(struct stm32_adc *adc)
+{
+ stm32_adc_clr_bits(adc, STM32F4_ADC_CR2, STM32F4_EXTEN_MASK);
+ stm32_adc_clr_bits(adc, STM32F4_ADC_SR, STM32F4_STRT);
+
+ stm32_adc_clr_bits(adc, STM32F4_ADC_CR1, STM32F4_SCAN);
+ stm32_adc_clr_bits(adc, STM32F4_ADC_CR2, STM32F4_ADON);
+}
+
+/**
+ * stm32_adc_single_conv() - Performs a single conversion
+ * @indio_dev: IIO device
+ * @chan: IIO channel
+ * @res: conversion result
+ *
+ * The function performs a single conversion on a given channel:
+ * - Program sequencer with one channel (e.g. in SQ1 with len = 1)
+ * - Use SW trigger
+ * - Start conversion, then wait for interrupt completion.
+ */
+static int stm32_adc_single_conv(struct iio_dev *indio_dev,
+ const struct iio_chan_spec *chan,
+ int *res)
+{
+ struct stm32_adc *adc = iio_priv(indio_dev);
+ long timeout;
+ u32 val;
+ u16 result;
+ int ret;
+
+ reinit_completion(&adc->completion);
+
+ adc->buffer = &result;
+
+ /* Program chan number in regular sequence */
+ val = stm32_adc_readl(adc, STM32F4_ADC_SQR3);
+ val &= ~STM32F4_SQ1_MASK;
+ val |= chan->channel << STM32F4_SQ1_SHIFT;
+ stm32_adc_writel(adc, STM32F4_ADC_SQR3, val);
+
+ /* Set regular sequence len (0 for 1 conversion) */
+ stm32_adc_clr_bits(adc, STM32F4_ADC_SQR1, STM32F4_L_MASK);
+
+ /* Trigger detection disabled (conversion can be launched in SW) */
+ stm32_adc_clr_bits(adc, STM32F4_ADC_CR2, STM32F4_EXTEN_MASK);
+
+ stm32_adc_conv_irq_enable(adc);
+
+ stm32_adc_start_conv(adc);
+
+ timeout = wait_for_completion_interruptible_timeout(
+ &adc->completion, STM32_ADC_TIMEOUT);
+ if (timeout == 0) {
+ ret = -ETIMEDOUT;
+ } else if (timeout < 0) {
+ ret = timeout;
+ } else {
+ *res = result;
+ ret = IIO_VAL_INT;
+ }
+
+ stm32_adc_stop_conv(adc);
+
+ stm32_adc_conv_irq_disable(adc);
+
+ return ret;
+}
+
+static int stm32_adc_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct stm32_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;
+ if (chan->type == IIO_VOLTAGE)
+ ret = stm32_adc_single_conv(indio_dev, chan, val);
+ else
+ ret = -EINVAL;
+ iio_device_release_direct_mode(indio_dev);
+ return ret;
+
+ case IIO_CHAN_INFO_SCALE:
+ *val = adc->common->vref_mv;
+ *val2 = chan->scan_type.realbits;
+ return IIO_VAL_FRACTIONAL_LOG2;
+
+ default:
+ return -EINVAL;
+ }
+}
+
+static irqreturn_t stm32_adc_isr(int irq, void *data)
+{
+ struct stm32_adc *adc = data;
+ u32 status = stm32_adc_readl(adc, STM32F4_ADC_SR);
+
+ if (status & STM32F4_EOC) {
+ *adc->buffer = stm32_adc_readw(adc, STM32F4_ADC_DR);
+ complete(&adc->completion);
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
+}
+
+static int stm32_adc_of_xlate(struct iio_dev *indio_dev,
+ const struct of_phandle_args *iiospec)
+{
+ int i;
+
+ for (i = 0; i < indio_dev->num_channels; i++)
+ if (indio_dev->channels[i].channel == iiospec->args[0])
+ return i;
+
+ return -EINVAL;
+}
+
+/**
+ * stm32_adc_debugfs_reg_access - read or write register value
+ *
+ * To read a value from an ADC register:
+ * echo [ADC reg offset] > direct_reg_access
+ * cat direct_reg_access
+ *
+ * To write a value in a ADC register:
+ * echo [ADC_reg_offset] [value] > direct_reg_access
+ */
+static int stm32_adc_debugfs_reg_access(struct iio_dev *indio_dev,
+ unsigned reg, unsigned writeval,
+ unsigned *readval)
+{
+ struct stm32_adc *adc = iio_priv(indio_dev);
+
+ if (!readval)
+ stm32_adc_writel(adc, reg, writeval);
+ else
+ *readval = stm32_adc_readl(adc, reg);
+
+ return 0;
+}
+
+static const struct iio_info stm32_adc_iio_info = {
+ .read_raw = stm32_adc_read_raw,
+ .debugfs_reg_access = stm32_adc_debugfs_reg_access,
+ .of_xlate = stm32_adc_of_xlate,
+ .driver_module = THIS_MODULE,
+};
+
+static void stm32_adc_chan_init_one(struct iio_dev *indio_dev,
+ struct iio_chan_spec *chan,
+ const struct stm32_adc_chan_spec *channel,
+ int scan_index)
+{
+ chan->type = channel->type;
+ chan->channel = channel->channel;
+ chan->datasheet_name = channel->name;
+ chan->scan_index = scan_index;
+ chan->indexed = 1;
+ chan->info_mask_separate = BIT(IIO_CHAN_INFO_RAW);
+ chan->info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE);
+ chan->scan_type.sign = 'u';
+ chan->scan_type.realbits = 12;
+ chan->scan_type.storagebits = 16;
+}
+
+static int stm32_adc_chan_of_init(struct iio_dev *indio_dev)
+{
+ struct device_node *node = indio_dev->dev.of_node;
+ struct property *prop;
+ const __be32 *cur;
+ struct iio_chan_spec *channels;
+ int scan_index = 0, num_channels;
+ u32 val;
+
+ num_channels = of_property_count_u32_elems(node, "st,adc-channels");
+ if (num_channels < 0 ||
+ num_channels >= ARRAY_SIZE(stm32f4_adc123_channels)) {
+ dev_err(&indio_dev->dev, "Bad st,adc-channels?\n");
+ return num_channels < 0 ? num_channels : -EINVAL;
+ }
+
+ channels = devm_kcalloc(&indio_dev->dev, num_channels,
+ sizeof(struct iio_chan_spec), GFP_KERNEL);
+ if (!channels)
+ return -ENOMEM;
+
+ of_property_for_each_u32(node, "st,adc-channels", prop, cur, val) {
+ if (val >= ARRAY_SIZE(stm32f4_adc123_channels)) {
+ dev_err(&indio_dev->dev, "Invalid channel %d\n", val);
+ return -EINVAL;
+ }
+ stm32_adc_chan_init_one(indio_dev, &channels[scan_index],
+ &stm32f4_adc123_channels[val],
+ scan_index);
+ scan_index++;
+ }
+
+ indio_dev->num_channels = scan_index;
+ indio_dev->channels = channels;
+
+ return 0;
+}
+
+static int stm32_adc_probe(struct platform_device *pdev)
+{
+ struct iio_dev *indio_dev;
+ struct stm32_adc *adc;
+ int ret;
+
+ if (!pdev->dev.of_node)
+ return -ENODEV;
+
+ indio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*adc));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ adc = iio_priv(indio_dev);
+ adc->common = dev_get_drvdata(pdev->dev.parent);
+ spin_lock_init(&adc->lock);
+ init_completion(&adc->completion);
+
+ indio_dev->name = dev_name(&pdev->dev);
+ indio_dev->dev.parent = &pdev->dev;
+ indio_dev->dev.of_node = pdev->dev.of_node;
+ indio_dev->info = &stm32_adc_iio_info;
+ indio_dev->modes = INDIO_DIRECT_MODE;
+
+ platform_set_drvdata(pdev, adc);
+
+ ret = of_property_read_u32(pdev->dev.of_node, "reg", &adc->offset);
+ if (ret != 0) {
+ dev_err(&pdev->dev, "missing reg property\n");
+ return -EINVAL;
+ }
+
+ adc->irq = platform_get_irq(pdev, 0);
+ if (adc->irq < 0) {
+ dev_err(&pdev->dev, "failed to get irq\n");
+ return adc->irq;
+ }
+
+ ret = devm_request_irq(&pdev->dev, adc->irq, stm32_adc_isr,
+ 0, pdev->name, adc);
+ if (ret) {
+ dev_err(&pdev->dev, "failed to request IRQ\n");
+ return ret;
+ }
+
+ adc->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(adc->clk)) {
+ dev_err(&pdev->dev, "Can't get clock\n");
+ return PTR_ERR(adc->clk);
+ }
+
+ ret = clk_prepare_enable(adc->clk);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "clk enable failed\n");
+ return ret;
+ }
+
+ ret = stm32_adc_chan_of_init(indio_dev);
+ if (ret < 0)
+ goto err_clk_disable;
+
+ ret = iio_device_register(indio_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "iio dev register failed\n");
+ goto err_clk_disable;
+ }
+
+ return 0;
+
+err_clk_disable:
+ clk_disable_unprepare(adc->clk);
+
+ return ret;
+}
+
+static int stm32_adc_remove(struct platform_device *pdev)
+{
+ struct stm32_adc *adc = platform_get_drvdata(pdev);
+ struct iio_dev *indio_dev = iio_priv_to_dev(adc);
+
+ iio_device_unregister(indio_dev);
+ clk_disable_unprepare(adc->clk);
+
+ return 0;
+}
+
+static const struct of_device_id stm32_adc_of_match[] = {
+ { .compatible = "st,stm32f4-adc" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, stm32_adc_of_match);
+
+static struct platform_driver stm32_adc_driver = {
+ .probe = stm32_adc_probe,
+ .remove = stm32_adc_remove,
+ .driver = {
+ .name = "stm32-adc",
+ .of_match_table = stm32_adc_of_match,
+ },
+};
+module_platform_driver(stm32_adc_driver);
+
+MODULE_AUTHOR("Fabrice Gasnier <fabrice.gasnier@st.com>");
+MODULE_DESCRIPTION("STMicroelectronics STM32 ADC IIO driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:stm32-adc");
diff --git a/drivers/iio/adc/ti-adc0832.c b/drivers/iio/adc/ti-adc0832.c
index f4ba23effe9a..e952e94a14af 100644
--- a/drivers/iio/adc/ti-adc0832.c
+++ b/drivers/iio/adc/ti-adc0832.c
@@ -14,6 +14,10 @@
#include <linux/spi/spi.h>
#include <linux/iio/iio.h>
#include <linux/regulator/consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
enum {
adc0831,
@@ -38,10 +42,16 @@ struct adc0832 {
.indexed = 1, \
.channel = chan, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
- .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_index = chan, \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 8, \
+ .storagebits = 8, \
+ }, \
}
-#define ADC0832_VOLTAGE_CHANNEL_DIFF(chan1, chan2) \
+#define ADC0832_VOLTAGE_CHANNEL_DIFF(chan1, chan2, si) \
{ \
.type = IIO_VOLTAGE, \
.indexed = 1, \
@@ -49,18 +59,26 @@ struct adc0832 {
.channel2 = (chan2), \
.differential = 1, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
- .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE) \
+ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
+ .scan_index = si, \
+ .scan_type = { \
+ .sign = 'u', \
+ .realbits = 8, \
+ .storagebits = 8, \
+ }, \
}
static const struct iio_chan_spec adc0831_channels[] = {
- ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1, 0),
+ IIO_CHAN_SOFT_TIMESTAMP(1),
};
static const struct iio_chan_spec adc0832_channels[] = {
ADC0832_VOLTAGE_CHANNEL(0),
ADC0832_VOLTAGE_CHANNEL(1),
- ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1),
- ADC0832_VOLTAGE_CHANNEL_DIFF(1, 0),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1, 2),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(1, 0, 3),
+ IIO_CHAN_SOFT_TIMESTAMP(4),
};
static const struct iio_chan_spec adc0834_channels[] = {
@@ -68,10 +86,11 @@ static const struct iio_chan_spec adc0834_channels[] = {
ADC0832_VOLTAGE_CHANNEL(1),
ADC0832_VOLTAGE_CHANNEL(2),
ADC0832_VOLTAGE_CHANNEL(3),
- ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1),
- ADC0832_VOLTAGE_CHANNEL_DIFF(1, 0),
- ADC0832_VOLTAGE_CHANNEL_DIFF(2, 3),
- ADC0832_VOLTAGE_CHANNEL_DIFF(3, 2),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1, 4),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(1, 0, 5),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(2, 3, 6),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(3, 2, 7),
+ IIO_CHAN_SOFT_TIMESTAMP(8),
};
static const struct iio_chan_spec adc0838_channels[] = {
@@ -83,14 +102,15 @@ static const struct iio_chan_spec adc0838_channels[] = {
ADC0832_VOLTAGE_CHANNEL(5),
ADC0832_VOLTAGE_CHANNEL(6),
ADC0832_VOLTAGE_CHANNEL(7),
- ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1),
- ADC0832_VOLTAGE_CHANNEL_DIFF(1, 0),
- ADC0832_VOLTAGE_CHANNEL_DIFF(2, 3),
- ADC0832_VOLTAGE_CHANNEL_DIFF(3, 2),
- ADC0832_VOLTAGE_CHANNEL_DIFF(4, 5),
- ADC0832_VOLTAGE_CHANNEL_DIFF(5, 4),
- ADC0832_VOLTAGE_CHANNEL_DIFF(6, 7),
- ADC0832_VOLTAGE_CHANNEL_DIFF(7, 6),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(0, 1, 8),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(1, 0, 9),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(2, 3, 10),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(3, 2, 11),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(4, 5, 12),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(5, 4, 13),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(6, 7, 14),
+ ADC0832_VOLTAGE_CHANNEL_DIFF(7, 6, 15),
+ IIO_CHAN_SOFT_TIMESTAMP(16),
};
static int adc0831_adc_conversion(struct adc0832 *adc)
@@ -178,6 +198,42 @@ static const struct iio_info adc0832_info = {
.driver_module = THIS_MODULE,
};
+static irqreturn_t adc0832_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct adc0832 *adc = iio_priv(indio_dev);
+ u8 data[24] = { }; /* 16x 1 byte ADC data + 8 bytes timestamp */
+ int scan_index;
+ int i = 0;
+
+ mutex_lock(&adc->lock);
+
+ for_each_set_bit(scan_index, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ const struct iio_chan_spec *scan_chan =
+ &indio_dev->channels[scan_index];
+ int ret = adc0832_adc_conversion(adc, scan_chan->channel,
+ scan_chan->differential);
+ if (ret < 0) {
+ dev_warn(&adc->spi->dev,
+ "failed to get conversion data\n");
+ goto out;
+ }
+
+ data[i] = ret;
+ i++;
+ }
+ iio_push_to_buffers_with_timestamp(indio_dev, data,
+ iio_get_time_ns(indio_dev));
+out:
+ mutex_unlock(&adc->lock);
+
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
static int adc0832_probe(struct spi_device *spi)
{
struct iio_dev *indio_dev;
@@ -233,9 +289,20 @@ static int adc0832_probe(struct spi_device *spi)
spi_set_drvdata(spi, indio_dev);
+ ret = iio_triggered_buffer_setup(indio_dev, NULL,
+ adc0832_trigger_handler, NULL);
+ if (ret)
+ goto err_reg_disable;
+
ret = iio_device_register(indio_dev);
if (ret)
- regulator_disable(adc->reg);
+ goto err_buffer_cleanup;
+
+ return 0;
+err_buffer_cleanup:
+ iio_triggered_buffer_cleanup(indio_dev);
+err_reg_disable:
+ regulator_disable(adc->reg);
return ret;
}
@@ -246,6 +313,7 @@ static int adc0832_remove(struct spi_device *spi)
struct adc0832 *adc = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
+ iio_triggered_buffer_cleanup(indio_dev);
regulator_disable(adc->reg);
return 0;
diff --git a/drivers/iio/adc/ti-adc161s626.c b/drivers/iio/adc/ti-adc161s626.c
index f94b69f9c288..4836a0d7aef5 100644
--- a/drivers/iio/adc/ti-adc161s626.c
+++ b/drivers/iio/adc/ti-adc161s626.c
@@ -27,6 +27,7 @@
#include <linux/iio/buffer.h>
#include <linux/iio/trigger_consumer.h>
#include <linux/iio/triggered_buffer.h>
+#include <linux/regulator/consumer.h>
#define TI_ADC_DRV_NAME "ti-adc161s626"
@@ -39,7 +40,9 @@ static const struct iio_chan_spec ti_adc141s626_channels[] = {
{
.type = IIO_VOLTAGE,
.channel = 0,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
.scan_index = 0,
.scan_type = {
.sign = 's',
@@ -54,7 +57,9 @@ static const struct iio_chan_spec ti_adc161s626_channels[] = {
{
.type = IIO_VOLTAGE,
.channel = 0,
- .info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+ BIT(IIO_CHAN_INFO_SCALE) |
+ BIT(IIO_CHAN_INFO_OFFSET),
.scan_index = 0,
.scan_type = {
.sign = 's',
@@ -68,6 +73,8 @@ static const struct iio_chan_spec ti_adc161s626_channels[] = {
struct ti_adc_data {
struct iio_dev *indio_dev;
struct spi_device *spi;
+ struct regulator *ref;
+
u8 read_size;
u8 shift;
@@ -135,18 +142,32 @@ static int ti_adc_read_raw(struct iio_dev *indio_dev,
struct ti_adc_data *data = iio_priv(indio_dev);
int ret;
- if (mask != IIO_CHAN_INFO_RAW)
- return -EINVAL;
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW:
+ ret = iio_device_claim_direct_mode(indio_dev);
+ if (ret)
+ return ret;
- ret = iio_device_claim_direct_mode(indio_dev);
- if (ret)
- return ret;
+ ret = ti_adc_read_measurement(data, chan, val);
+ iio_device_release_direct_mode(indio_dev);
- ret = ti_adc_read_measurement(data, chan, val);
- iio_device_release_direct_mode(indio_dev);
+ if (ret)
+ return ret;
- if (!ret)
return IIO_VAL_INT;
+ case IIO_CHAN_INFO_SCALE:
+ ret = regulator_get_voltage(data->ref);
+ if (ret < 0)
+ return ret;
+
+ *val = ret / 1000;
+ *val2 = chan->scan_type.realbits;
+
+ return IIO_VAL_FRACTIONAL_LOG2;
+ case IIO_CHAN_INFO_OFFSET:
+ *val = 1 << (chan->scan_type.realbits - 1);
+ return IIO_VAL_INT;
+ }
return 0;
}
@@ -191,10 +212,17 @@ static int ti_adc_probe(struct spi_device *spi)
break;
}
+ data->ref = devm_regulator_get(&spi->dev, "vdda");
+ if (!IS_ERR(data->ref)) {
+ ret = regulator_enable(data->ref);
+ if (ret < 0)
+ return ret;
+ }
+
ret = iio_triggered_buffer_setup(indio_dev, NULL,
ti_adc_trigger_handler, NULL);
if (ret)
- return ret;
+ goto error_regulator_disable;
ret = iio_device_register(indio_dev);
if (ret)
@@ -205,15 +233,20 @@ static int ti_adc_probe(struct spi_device *spi)
error_unreg_buffer:
iio_triggered_buffer_cleanup(indio_dev);
+error_regulator_disable:
+ regulator_disable(data->ref);
+
return ret;
}
static int ti_adc_remove(struct spi_device *spi)
{
struct iio_dev *indio_dev = spi_get_drvdata(spi);
+ struct ti_adc_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
iio_triggered_buffer_cleanup(indio_dev);
+ regulator_disable(data->ref);
return 0;
}
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index c3cfacca2541..ad9dec30bb30 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -30,10 +30,28 @@
#include <linux/iio/buffer.h>
#include <linux/iio/kfifo_buf.h>
+#include <linux/dmaengine.h>
+#include <linux/dma-mapping.h>
+
+#define DMA_BUFFER_SIZE SZ_2K
+
+struct tiadc_dma {
+ struct dma_slave_config conf;
+ struct dma_chan *chan;
+ dma_addr_t addr;
+ dma_cookie_t cookie;
+ u8 *buf;
+ int current_period;
+ int period_size;
+ u8 fifo_thresh;
+};
+
struct tiadc_device {
struct ti_tscadc_dev *mfd_tscadc;
+ struct tiadc_dma dma;
struct mutex fifo1_lock; /* to protect fifo access */
int channels;
+ int total_ch_enabled;
u8 channel_line[8];
u8 channel_step[8];
int buffer_en_ch_steps;
@@ -198,6 +216,67 @@ static irqreturn_t tiadc_worker_h(int irq, void *private)
return IRQ_HANDLED;
}
+static void tiadc_dma_rx_complete(void *param)
+{
+ struct iio_dev *indio_dev = param;
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct tiadc_dma *dma = &adc_dev->dma;
+ u8 *data;
+ int i;
+
+ data = dma->buf + dma->current_period * dma->period_size;
+ dma->current_period = 1 - dma->current_period; /* swap the buffer ID */
+
+ for (i = 0; i < dma->period_size; i += indio_dev->scan_bytes) {
+ iio_push_to_buffers(indio_dev, data);
+ data += indio_dev->scan_bytes;
+ }
+}
+
+static int tiadc_start_dma(struct iio_dev *indio_dev)
+{
+ struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct tiadc_dma *dma = &adc_dev->dma;
+ struct dma_async_tx_descriptor *desc;
+
+ dma->current_period = 0; /* We start to fill period 0 */
+ /*
+ * Make the fifo thresh as the multiple of total number of
+ * channels enabled, so make sure that cyclic DMA period
+ * length is also a multiple of total number of channels
+ * enabled. This ensures that no invalid data is reported
+ * to the stack via iio_push_to_buffers().
+ */
+ dma->fifo_thresh = rounddown(FIFO1_THRESHOLD + 1,
+ adc_dev->total_ch_enabled) - 1;
+ /* Make sure that period length is multiple of fifo thresh level */
+ dma->period_size = rounddown(DMA_BUFFER_SIZE / 2,
+ (dma->fifo_thresh + 1) * sizeof(u16));
+
+ dma->conf.src_maxburst = dma->fifo_thresh + 1;
+ dmaengine_slave_config(dma->chan, &dma->conf);
+
+ desc = dmaengine_prep_dma_cyclic(dma->chan, dma->addr,
+ dma->period_size * 2,
+ dma->period_size, DMA_DEV_TO_MEM,
+ DMA_PREP_INTERRUPT);
+ if (!desc)
+ return -EBUSY;
+
+ desc->callback = tiadc_dma_rx_complete;
+ desc->callback_param = indio_dev;
+
+ dma->cookie = dmaengine_submit(desc);
+
+ dma_async_issue_pending(dma->chan);
+
+ tiadc_writel(adc_dev, REG_FIFO1THR, dma->fifo_thresh);
+ tiadc_writel(adc_dev, REG_DMA1REQ, dma->fifo_thresh);
+ tiadc_writel(adc_dev, REG_DMAENABLE_SET, DMA_FIFO1);
+
+ return 0;
+}
+
static int tiadc_buffer_preenable(struct iio_dev *indio_dev)
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
@@ -218,20 +297,30 @@ static int tiadc_buffer_preenable(struct iio_dev *indio_dev)
static int tiadc_buffer_postenable(struct iio_dev *indio_dev)
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct tiadc_dma *dma = &adc_dev->dma;
+ unsigned int irq_enable;
unsigned int enb = 0;
u8 bit;
tiadc_step_config(indio_dev);
- for_each_set_bit(bit, indio_dev->active_scan_mask, adc_dev->channels)
+ for_each_set_bit(bit, indio_dev->active_scan_mask, adc_dev->channels) {
enb |= (get_adc_step_bit(adc_dev, bit) << 1);
+ adc_dev->total_ch_enabled++;
+ }
adc_dev->buffer_en_ch_steps = enb;
+ if (dma->chan)
+ tiadc_start_dma(indio_dev);
+
am335x_tsc_se_set_cache(adc_dev->mfd_tscadc, enb);
tiadc_writel(adc_dev, REG_IRQSTATUS, IRQENB_FIFO1THRES
| IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW);
- tiadc_writel(adc_dev, REG_IRQENABLE, IRQENB_FIFO1THRES
- | IRQENB_FIFO1OVRRUN);
+
+ irq_enable = IRQENB_FIFO1OVRRUN;
+ if (!dma->chan)
+ irq_enable |= IRQENB_FIFO1THRES;
+ tiadc_writel(adc_dev, REG_IRQENABLE, irq_enable);
return 0;
}
@@ -239,12 +328,18 @@ static int tiadc_buffer_postenable(struct iio_dev *indio_dev)
static int tiadc_buffer_predisable(struct iio_dev *indio_dev)
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct tiadc_dma *dma = &adc_dev->dma;
int fifo1count, i, read;
tiadc_writel(adc_dev, REG_IRQCLR, (IRQENB_FIFO1THRES |
IRQENB_FIFO1OVRRUN | IRQENB_FIFO1UNDRFLW));
am335x_tsc_se_clr(adc_dev->mfd_tscadc, adc_dev->buffer_en_ch_steps);
adc_dev->buffer_en_ch_steps = 0;
+ adc_dev->total_ch_enabled = 0;
+ if (dma->chan) {
+ tiadc_writel(adc_dev, REG_DMAENABLE_CLEAR, 0x2);
+ dmaengine_terminate_async(dma->chan);
+ }
/* Flush FIFO of leftover data in the time it takes to disable adc */
fifo1count = tiadc_readl(adc_dev, REG_FIFO1CNT);
@@ -430,6 +525,41 @@ static const struct iio_info tiadc_info = {
.driver_module = THIS_MODULE,
};
+static int tiadc_request_dma(struct platform_device *pdev,
+ struct tiadc_device *adc_dev)
+{
+ struct tiadc_dma *dma = &adc_dev->dma;
+ dma_cap_mask_t mask;
+
+ /* Default slave configuration parameters */
+ dma->conf.direction = DMA_DEV_TO_MEM;
+ dma->conf.src_addr_width = DMA_SLAVE_BUSWIDTH_2_BYTES;
+ dma->conf.src_addr = adc_dev->mfd_tscadc->tscadc_phys_base + REG_FIFO1;
+
+ dma_cap_zero(mask);
+ dma_cap_set(DMA_CYCLIC, mask);
+
+ /* Get a channel for RX */
+ dma->chan = dma_request_chan(adc_dev->mfd_tscadc->dev, "fifo1");
+ if (IS_ERR(dma->chan)) {
+ int ret = PTR_ERR(dma->chan);
+
+ dma->chan = NULL;
+ return ret;
+ }
+
+ /* RX buffer */
+ dma->buf = dma_alloc_coherent(dma->chan->device->dev, DMA_BUFFER_SIZE,
+ &dma->addr, GFP_KERNEL);
+ if (!dma->buf)
+ goto err;
+
+ return 0;
+err:
+ dma_release_channel(dma->chan);
+ return -ENOMEM;
+}
+
static int tiadc_parse_dt(struct platform_device *pdev,
struct tiadc_device *adc_dev)
{
@@ -512,8 +642,14 @@ static int tiadc_probe(struct platform_device *pdev)
platform_set_drvdata(pdev, indio_dev);
+ err = tiadc_request_dma(pdev, adc_dev);
+ if (err && err == -EPROBE_DEFER)
+ goto err_dma;
+
return 0;
+err_dma:
+ iio_device_unregister(indio_dev);
err_buffer_unregister:
tiadc_iio_buffered_hardware_remove(indio_dev);
err_free_channels:
@@ -525,8 +661,14 @@ static int tiadc_remove(struct platform_device *pdev)
{
struct iio_dev *indio_dev = platform_get_drvdata(pdev);
struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct tiadc_dma *dma = &adc_dev->dma;
u32 step_en;
+ if (dma->chan) {
+ dma_free_coherent(dma->chan->device->dev, DMA_BUFFER_SIZE,
+ dma->buf, dma->addr);
+ dma_release_channel(dma->chan);
+ }
iio_device_unregister(indio_dev);
tiadc_iio_buffered_hardware_remove(indio_dev);
tiadc_channels_remove(indio_dev);
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-17 14:54:35 +0300