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path: root/drivers/iio/adc/ad_sigma_delta.c
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Diffstat (limited to 'drivers/iio/adc/ad_sigma_delta.c')
-rw-r--r--drivers/iio/adc/ad_sigma_delta.c532
1 files changed, 381 insertions, 151 deletions
diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c
index a2b87f6b7a07..7852884703b0 100644
--- a/drivers/iio/adc/ad_sigma_delta.c
+++ b/drivers/iio/adc/ad_sigma_delta.c
@@ -7,43 +7,55 @@
*/
#include <linux/align.h>
-#include <linux/interrupt.h>
+#include <linux/bitmap.h>
+#include <linux/bitops.h>
+#include <linux/cleanup.h>
+#include <linux/completion.h>
#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/spi/spi.h>
#include <linux/err.h>
+#include <linux/export.h>
+#include <linux/find.h>
+#include <linux/gpio/consumer.h>
+#include <linux/interrupt.h>
#include <linux/module.h>
+#include <linux/property.h>
+#include <linux/slab.h>
+#include <linux/spi/offload/consumer.h>
+#include <linux/spi/spi.h>
+#include <linux/spinlock.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/unaligned.h>
-#include <linux/iio/iio.h>
-#include <linux/iio/sysfs.h>
+#include <linux/iio/adc/ad_sigma_delta.h>
+#include <linux/iio/buffer-dmaengine.h>
#include <linux/iio/buffer.h>
-#include <linux/iio/trigger.h>
+#include <linux/iio/iio.h>
#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/trigger.h>
#include <linux/iio/triggered_buffer.h>
-#include <linux/iio/adc/ad_sigma_delta.h>
-
-#include <asm/unaligned.h>
-
#define AD_SD_COMM_CHAN_MASK 0x3
#define AD_SD_REG_COMM 0x00
+#define AD_SD_REG_STATUS 0x00
#define AD_SD_REG_DATA 0x03
+#define AD_SD_REG_STATUS_RDY 0x80
+
/**
* ad_sd_set_comm() - Set communications register
*
* @sigma_delta: The sigma delta device
* @comm: New value for the communications register
*/
-void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, uint8_t comm)
+void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, u8 comm)
{
/* Some variants use the lower two bits of the communications register
* to select the channel */
sigma_delta->comm = comm & AD_SD_COMM_CHAN_MASK;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_set_comm, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_set_comm, "IIO_AD_SIGMA_DELTA");
/**
* ad_sd_write_reg() - Write a register
@@ -58,7 +70,7 @@ EXPORT_SYMBOL_NS_GPL(ad_sd_set_comm, IIO_AD_SIGMA_DELTA);
int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
unsigned int size, unsigned int val)
{
- uint8_t *data = sigma_delta->tx_buf;
+ u8 *data = sigma_delta->tx_buf;
struct spi_transfer t = {
.tx_buf = data,
.len = size + 1,
@@ -95,12 +107,20 @@ int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg,
return ret;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_write_reg, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_write_reg, "IIO_AD_SIGMA_DELTA");
+
+static void ad_sd_set_read_reg_addr(struct ad_sigma_delta *sigma_delta, u8 reg,
+ u8 *data)
+{
+ data[0] = reg << sigma_delta->info->addr_shift;
+ data[0] |= sigma_delta->info->read_mask;
+ data[0] |= sigma_delta->comm;
+}
static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta,
- unsigned int reg, unsigned int size, uint8_t *val)
+ unsigned int reg, unsigned int size, u8 *val)
{
- uint8_t *data = sigma_delta->tx_buf;
+ u8 *data = sigma_delta->tx_buf;
int ret;
struct spi_transfer t[] = {
{
@@ -109,7 +129,7 @@ static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta,
}, {
.rx_buf = val,
.len = size,
- .cs_change = sigma_delta->bus_locked,
+ .cs_change = sigma_delta->keep_cs_asserted,
},
};
struct spi_message m;
@@ -117,9 +137,7 @@ static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta,
spi_message_init(&m);
if (sigma_delta->info->has_registers) {
- data[0] = reg << sigma_delta->info->addr_shift;
- data[0] |= sigma_delta->info->read_mask;
- data[0] |= sigma_delta->comm;
+ ad_sd_set_read_reg_addr(sigma_delta, reg, data);
spi_message_add_tail(&t[0], &m);
}
spi_message_add_tail(&t[1], &m);
@@ -172,24 +190,23 @@ int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta,
out:
return ret;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_read_reg, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_read_reg, "IIO_AD_SIGMA_DELTA");
/**
* ad_sd_reset() - Reset the serial interface
*
* @sigma_delta: The sigma delta device
- * @reset_length: Number of SCLKs with DIN = 1
*
* Returns 0 on success, an error code otherwise.
**/
-int ad_sd_reset(struct ad_sigma_delta *sigma_delta,
- unsigned int reset_length)
+int ad_sd_reset(struct ad_sigma_delta *sigma_delta)
{
- uint8_t *buf;
+ unsigned int reset_length = sigma_delta->info->num_resetclks;
unsigned int size;
+ u8 *buf;
int ret;
- size = DIV_ROUND_UP(reset_length, 8);
+ size = BITS_TO_BYTES(reset_length);
buf = kcalloc(size, sizeof(*buf), GFP_KERNEL);
if (!buf)
return -ENOMEM;
@@ -200,7 +217,106 @@ int ad_sd_reset(struct ad_sigma_delta *sigma_delta,
return ret;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_reset, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_reset, "IIO_AD_SIGMA_DELTA");
+
+static bool ad_sd_disable_irq(struct ad_sigma_delta *sigma_delta)
+{
+ guard(spinlock_irqsave)(&sigma_delta->irq_lock);
+
+ /* It's already off, return false to indicate nothing was changed */
+ if (sigma_delta->irq_dis)
+ return false;
+
+ sigma_delta->irq_dis = true;
+ disable_irq_nosync(sigma_delta->irq_line);
+ return true;
+}
+
+static void ad_sd_enable_irq(struct ad_sigma_delta *sigma_delta)
+{
+ guard(spinlock_irqsave)(&sigma_delta->irq_lock);
+
+ sigma_delta->irq_dis = false;
+ enable_irq(sigma_delta->irq_line);
+}
+
+#define AD_SD_CLEAR_DATA_BUFLEN 9
+
+/* Called with `sigma_delta->bus_locked == true` only. */
+static int ad_sigma_delta_clear_pending_event(struct ad_sigma_delta *sigma_delta)
+{
+ bool pending_event;
+ unsigned int data_read_len = BITS_TO_BYTES(sigma_delta->info->num_resetclks);
+ u8 *data;
+ struct spi_transfer t[] = {
+ {
+ .len = 1,
+ }, {
+ .len = data_read_len,
+ }
+ };
+ struct spi_message m;
+ int ret;
+
+ /*
+ * Read R̅D̅Y̅ pin (if possible) or status register to check if there is an
+ * old event.
+ */
+ if (sigma_delta->rdy_gpiod) {
+ pending_event = gpiod_get_value(sigma_delta->rdy_gpiod);
+ } else {
+ unsigned int status_reg;
+
+ ret = ad_sd_read_reg(sigma_delta, AD_SD_REG_STATUS, 1, &status_reg);
+ if (ret)
+ return ret;
+
+ pending_event = !(status_reg & AD_SD_REG_STATUS_RDY);
+ }
+
+ if (!pending_event)
+ return 0;
+
+ /*
+ * In general the size of the data register is unknown. It varies from
+ * device to device, might be one byte longer if CONTROL.DATA_STATUS is
+ * set and even varies on some devices depending on which input is
+ * selected. So send one byte to start reading the data register and
+ * then just clock for some bytes with DIN (aka MOSI) high to not
+ * confuse the register access state machine after the data register was
+ * completely read. Note however that the sequence length must be
+ * shorter than the reset procedure.
+ */
+
+ data = kzalloc(data_read_len + 1, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ spi_message_init(&m);
+ if (sigma_delta->info->has_registers) {
+ unsigned int data_reg = sigma_delta->info->data_reg ?: AD_SD_REG_DATA;
+
+ ad_sd_set_read_reg_addr(sigma_delta, data_reg, data);
+ t[0].tx_buf = data;
+ spi_message_add_tail(&t[0], &m);
+ }
+
+ /*
+ * The first transferred byte is part of the real data register,
+ * so this doesn't need to be 0xff. In the remaining
+ * `data_read_len - 1` bytes are less than $num_resetclks ones.
+ */
+ t[1].tx_buf = data + 1;
+ data[1] = 0x00;
+ memset(data + 2, 0xff, data_read_len - 1);
+ spi_message_add_tail(&t[1], &m);
+
+ ret = spi_sync_locked(sigma_delta->spi, &m);
+
+ kfree(data);
+
+ return ret;
+}
int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta,
unsigned int mode, unsigned int channel)
@@ -217,16 +333,18 @@ int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta,
sigma_delta->keep_cs_asserted = true;
reinit_completion(&sigma_delta->completion);
+ ret = ad_sigma_delta_clear_pending_event(sigma_delta);
+ if (ret)
+ goto out;
+
ret = ad_sigma_delta_set_mode(sigma_delta, mode);
if (ret < 0)
goto out;
- sigma_delta->irq_dis = false;
- enable_irq(sigma_delta->irq_line);
+ ad_sd_enable_irq(sigma_delta);
time_left = wait_for_completion_timeout(&sigma_delta->completion, 2 * HZ);
if (time_left == 0) {
- sigma_delta->irq_dis = true;
- disable_irq_nosync(sigma_delta->irq_line);
+ ad_sd_disable_irq(sigma_delta);
ret = -EIO;
} else {
ret = 0;
@@ -234,12 +352,13 @@ int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta,
out:
sigma_delta->keep_cs_asserted = false;
ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE);
+ ad_sigma_delta_disable_one(sigma_delta, channel);
sigma_delta->bus_locked = false;
spi_bus_unlock(sigma_delta->spi->controller);
return ret;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate, "IIO_AD_SIGMA_DELTA");
/**
* ad_sd_calibrate_all() - Performs channel calibration
@@ -263,7 +382,7 @@ int ad_sd_calibrate_all(struct ad_sigma_delta *sigma_delta,
return 0;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate_all, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate_all, "IIO_AD_SIGMA_DELTA");
/**
* ad_sigma_delta_single_conversion() - Performs a single data conversion
@@ -281,21 +400,25 @@ int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev,
unsigned int data_reg;
int ret = 0;
- ret = iio_device_claim_direct_mode(indio_dev);
- if (ret)
- return ret;
+ if (!iio_device_claim_direct(indio_dev))
+ return -EBUSY;
- ad_sigma_delta_set_channel(sigma_delta, chan->address);
+ ret = ad_sigma_delta_set_channel(sigma_delta, chan->address);
+ if (ret)
+ goto out_release;
spi_bus_lock(sigma_delta->spi->controller);
sigma_delta->bus_locked = true;
sigma_delta->keep_cs_asserted = true;
reinit_completion(&sigma_delta->completion);
+ ret = ad_sigma_delta_clear_pending_event(sigma_delta);
+ if (ret)
+ goto out_unlock;
+
ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_SINGLE);
- sigma_delta->irq_dis = false;
- enable_irq(sigma_delta->irq_line);
+ ad_sd_enable_irq(sigma_delta);
ret = wait_for_completion_interruptible_timeout(
&sigma_delta->completion, HZ);
@@ -310,20 +433,21 @@ int ad_sigma_delta_single_conversion(struct iio_dev *indio_dev,
data_reg = AD_SD_REG_DATA;
ret = ad_sd_read_reg(sigma_delta, data_reg,
- DIV_ROUND_UP(chan->scan_type.realbits + chan->scan_type.shift, 8),
+ BITS_TO_BYTES(chan->scan_type.realbits + chan->scan_type.shift),
&raw_sample);
out:
- if (!sigma_delta->irq_dis) {
- disable_irq_nosync(sigma_delta->irq_line);
- sigma_delta->irq_dis = true;
- }
+ ad_sd_disable_irq(sigma_delta);
- sigma_delta->keep_cs_asserted = false;
ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE);
+ ad_sigma_delta_disable_one(sigma_delta, chan->address);
+
+out_unlock:
+ sigma_delta->keep_cs_asserted = false;
sigma_delta->bus_locked = false;
spi_bus_unlock(sigma_delta->spi->controller);
- iio_device_release_direct_mode(indio_dev);
+out_release:
+ iio_device_release_direct(indio_dev);
if (ret)
return ret;
@@ -338,19 +462,20 @@ out:
return IIO_VAL_INT;
}
-EXPORT_SYMBOL_NS_GPL(ad_sigma_delta_single_conversion, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sigma_delta_single_conversion, "IIO_AD_SIGMA_DELTA");
static int ad_sd_buffer_postenable(struct iio_dev *indio_dev)
{
struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
- unsigned int i, slot, samples_buf_size;
- unsigned int channel;
- uint8_t *samples_buf;
+ const struct iio_scan_type *scan_type = &indio_dev->channels[0].scan_type;
+ struct spi_transfer *xfer = sigma_delta->sample_xfer;
+ unsigned int i, slot, channel;
+ u8 *samples_buf;
int ret;
if (sigma_delta->num_slots == 1) {
channel = find_first_bit(indio_dev->active_scan_mask,
- indio_dev->masklength);
+ iio_get_masklength(indio_dev));
ret = ad_sigma_delta_set_channel(sigma_delta,
indio_dev->channels[channel].address);
if (ret)
@@ -363,7 +488,7 @@ static int ad_sd_buffer_postenable(struct iio_dev *indio_dev)
* implementation is mandatory.
*/
slot = 0;
- for_each_set_bit(i, indio_dev->active_scan_mask, indio_dev->masklength) {
+ iio_for_each_active_channel(indio_dev, i) {
sigma_delta->slots[slot] = indio_dev->channels[i].address;
slot++;
}
@@ -372,50 +497,103 @@ static int ad_sd_buffer_postenable(struct iio_dev *indio_dev)
sigma_delta->active_slots = slot;
sigma_delta->current_slot = 0;
- if (sigma_delta->active_slots > 1) {
- ret = ad_sigma_delta_append_status(sigma_delta, true);
- if (ret)
- return ret;
+ if (ad_sigma_delta_has_spi_offload(sigma_delta)) {
+ xfer[1].offload_flags = SPI_OFFLOAD_XFER_RX_STREAM;
+ xfer[1].bits_per_word = scan_type->realbits;
+ xfer[1].len = spi_bpw_to_bytes(scan_type->realbits);
+ } else {
+ unsigned int samples_buf_size, scan_size;
+
+ if (sigma_delta->active_slots > 1) {
+ ret = ad_sigma_delta_append_status(sigma_delta, true);
+ if (ret)
+ return ret;
+ }
+
+ samples_buf_size =
+ ALIGN(slot * BITS_TO_BYTES(scan_type->storagebits),
+ sizeof(s64));
+ samples_buf_size += sizeof(s64);
+ samples_buf = devm_krealloc(&sigma_delta->spi->dev,
+ sigma_delta->samples_buf,
+ samples_buf_size, GFP_KERNEL);
+ if (!samples_buf)
+ return -ENOMEM;
+
+ sigma_delta->samples_buf = samples_buf;
+ scan_size = BITS_TO_BYTES(scan_type->realbits + scan_type->shift);
+ /* For 24-bit data, there is an extra byte of padding. */
+ xfer[1].rx_buf = &sigma_delta->rx_buf[scan_size == 3 ? 1 : 0];
+ xfer[1].len = scan_size + (sigma_delta->status_appended ? 1 : 0);
}
+ xfer[1].cs_change = 1;
- samples_buf_size = ALIGN(slot * indio_dev->channels[0].scan_type.storagebits, 8);
- samples_buf_size += sizeof(int64_t);
- samples_buf = devm_krealloc(&sigma_delta->spi->dev, sigma_delta->samples_buf,
- samples_buf_size, GFP_KERNEL);
- if (!samples_buf)
- return -ENOMEM;
+ if (sigma_delta->info->has_registers) {
+ xfer[0].tx_buf = &sigma_delta->sample_addr;
+ xfer[0].len = 1;
+
+ ad_sd_set_read_reg_addr(sigma_delta,
+ sigma_delta->info->data_reg ?: AD_SD_REG_DATA,
+ &sigma_delta->sample_addr);
+ spi_message_init_with_transfers(&sigma_delta->sample_msg, xfer, 2);
+ } else {
+ spi_message_init_with_transfers(&sigma_delta->sample_msg,
+ &xfer[1], 1);
+ }
+
+ sigma_delta->sample_msg.offload = sigma_delta->offload;
- sigma_delta->samples_buf = samples_buf;
+ ret = spi_optimize_message(sigma_delta->spi, &sigma_delta->sample_msg);
+ if (ret)
+ return ret;
spi_bus_lock(sigma_delta->spi->controller);
sigma_delta->bus_locked = true;
sigma_delta->keep_cs_asserted = true;
+ ret = ad_sigma_delta_clear_pending_event(sigma_delta);
+ if (ret)
+ goto err_unlock;
+
ret = ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_CONTINUOUS);
if (ret)
goto err_unlock;
- sigma_delta->irq_dis = false;
- enable_irq(sigma_delta->irq_line);
+ if (ad_sigma_delta_has_spi_offload(sigma_delta)) {
+ struct spi_offload_trigger_config config = {
+ .type = SPI_OFFLOAD_TRIGGER_DATA_READY,
+ };
+
+ ret = spi_offload_trigger_enable(sigma_delta->offload,
+ sigma_delta->offload_trigger,
+ &config);
+ if (ret)
+ goto err_unlock;
+ } else {
+ ad_sd_enable_irq(sigma_delta);
+ }
return 0;
err_unlock:
spi_bus_unlock(sigma_delta->spi->controller);
+ spi_unoptimize_message(&sigma_delta->sample_msg);
return ret;
}
-static int ad_sd_buffer_postdisable(struct iio_dev *indio_dev)
+static int ad_sd_buffer_predisable(struct iio_dev *indio_dev)
{
struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
- reinit_completion(&sigma_delta->completion);
- wait_for_completion_timeout(&sigma_delta->completion, HZ);
+ if (ad_sigma_delta_has_spi_offload(sigma_delta)) {
+ spi_offload_trigger_disable(sigma_delta->offload,
+ sigma_delta->offload_trigger);
+ } else {
+ reinit_completion(&sigma_delta->completion);
+ wait_for_completion_timeout(&sigma_delta->completion, HZ);
- if (!sigma_delta->irq_dis) {
- disable_irq_nosync(sigma_delta->irq_line);
- sigma_delta->irq_dis = true;
+ ad_sd_disable_irq(sigma_delta);
}
sigma_delta->keep_cs_asserted = false;
@@ -426,57 +604,32 @@ static int ad_sd_buffer_postdisable(struct iio_dev *indio_dev)
ad_sigma_delta_disable_all(sigma_delta);
sigma_delta->bus_locked = false;
- return spi_bus_unlock(sigma_delta->spi->controller);
+ spi_bus_unlock(sigma_delta->spi->controller);
+ spi_unoptimize_message(&sigma_delta->sample_msg);
+
+ return 0;
}
static irqreturn_t ad_sd_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
struct iio_dev *indio_dev = pf->indio_dev;
+ const struct iio_scan_type *scan_type = &indio_dev->channels[0].scan_type;
struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
- uint8_t *data = sigma_delta->rx_buf;
- unsigned int transfer_size;
+ u8 *data = sigma_delta->rx_buf;
unsigned int sample_size;
unsigned int sample_pos;
unsigned int status_pos;
unsigned int reg_size;
- unsigned int data_reg;
-
- reg_size = indio_dev->channels[0].scan_type.realbits +
- indio_dev->channels[0].scan_type.shift;
- reg_size = DIV_ROUND_UP(reg_size, 8);
-
- if (sigma_delta->info->data_reg != 0)
- data_reg = sigma_delta->info->data_reg;
- else
- data_reg = AD_SD_REG_DATA;
-
- /* Status word will be appended to the sample during transfer */
- if (sigma_delta->status_appended)
- transfer_size = reg_size + 1;
- else
- transfer_size = reg_size;
+ int ret;
- switch (reg_size) {
- case 4:
- case 2:
- case 1:
- status_pos = reg_size;
- ad_sd_read_reg_raw(sigma_delta, data_reg, transfer_size, &data[0]);
- break;
- case 3:
- /*
- * Data array after transfer will look like (if status is appended):
- * data[] = { [0][sample][sample][sample][status] }
- * Keeping the first byte 0 shifts the status postion by 1 byte to the right.
- */
- status_pos = reg_size + 1;
+ reg_size = BITS_TO_BYTES(scan_type->realbits + scan_type->shift);
+ /* For 24-bit data, there is an extra byte of padding. */
+ status_pos = reg_size + (reg_size == 3 ? 1 : 0);
- /* We store 24 bit samples in a 32 bit word. Keep the upper
- * byte set to zero. */
- ad_sd_read_reg_raw(sigma_delta, data_reg, transfer_size, &data[1]);
- break;
- }
+ ret = spi_sync_locked(sigma_delta->spi, &sigma_delta->sample_msg);
+ if (ret)
+ goto irq_handled;
/*
* For devices sampling only one channel at
@@ -502,7 +655,7 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p)
}
}
- sample_size = indio_dev->channels[0].scan_type.storagebits / 8;
+ sample_size = BITS_TO_BYTES(scan_type->storagebits);
sample_pos = sample_size * sigma_delta->current_slot;
memcpy(&sigma_delta->samples_buf[sample_pos], data, sample_size);
sigma_delta->current_slot++;
@@ -515,8 +668,7 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p)
irq_handled:
iio_trigger_notify_done(indio_dev->trig);
- sigma_delta->irq_dis = false;
- enable_irq(sigma_delta->irq_line);
+ ad_sd_enable_irq(sigma_delta);
return IRQ_HANDLED;
}
@@ -525,12 +677,12 @@ static bool ad_sd_validate_scan_mask(struct iio_dev *indio_dev, const unsigned l
{
struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
- return bitmap_weight(mask, indio_dev->masklength) <= sigma_delta->num_slots;
+ return bitmap_weight(mask, iio_get_masklength(indio_dev)) <= sigma_delta->num_slots;
}
static const struct iio_buffer_setup_ops ad_sd_buffer_setup_ops = {
.postenable = &ad_sd_buffer_postenable,
- .postdisable = &ad_sd_buffer_postdisable,
+ .predisable = &ad_sd_buffer_predisable,
.validate_scan_mask = &ad_sd_validate_scan_mask,
};
@@ -538,12 +690,32 @@ static irqreturn_t ad_sd_data_rdy_trig_poll(int irq, void *private)
{
struct ad_sigma_delta *sigma_delta = private;
- complete(&sigma_delta->completion);
- disable_irq_nosync(irq);
- sigma_delta->irq_dis = true;
- iio_trigger_poll(sigma_delta->trig);
+ /*
+ * AD7124 and a few others use the same physical line for interrupt
+ * reporting (R̅D̅Y̅) and MISO.
+ * As MISO toggles when reading a register, this likely results in a
+ * pending interrupt. This has two consequences: a) The irq might
+ * trigger immediately after it's enabled even though the conversion
+ * isn't done yet; and b) checking the STATUS register's R̅D̅Y̅ flag is
+ * off-limits as reading that would trigger another irq event.
+ *
+ * So read the MOSI line as GPIO (if available) and only trigger the irq
+ * if the line is active. Without such a GPIO assume this is a valid
+ * interrupt.
+ *
+ * Also as disable_irq_nosync() is used to disable the irq, only act if
+ * the irq wasn't disabled before.
+ */
+ if ((!sigma_delta->rdy_gpiod || gpiod_get_value(sigma_delta->rdy_gpiod)) &&
+ ad_sd_disable_irq(sigma_delta)) {
+ complete(&sigma_delta->completion);
+ if (sigma_delta->trig)
+ iio_trigger_poll(sigma_delta->trig);
- return IRQ_HANDLED;
+ return IRQ_HANDLED;
+ }
+
+ return IRQ_NONE;
}
/**
@@ -563,25 +735,14 @@ int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig)
return 0;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_validate_trigger, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_validate_trigger, "IIO_AD_SIGMA_DELTA");
static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_dev)
{
struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev);
- unsigned long irq_flags = irq_get_trigger_type(sigma_delta->spi->irq);
+ unsigned long irq_flags = irq_get_trigger_type(sigma_delta->irq_line);
int ret;
- if (dev != &sigma_delta->spi->dev) {
- dev_err(dev, "Trigger parent should be '%s', got '%s'\n",
- dev_name(dev), dev_name(&sigma_delta->spi->dev));
- return -EFAULT;
- }
-
- sigma_delta->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name,
- iio_device_id(indio_dev));
- if (sigma_delta->trig == NULL)
- return -ENOMEM;
-
init_completion(&sigma_delta->completion);
sigma_delta->irq_dis = true;
@@ -601,14 +762,33 @@ static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_de
if (ret)
return ret;
- iio_trigger_set_drvdata(sigma_delta->trig, sigma_delta);
+ if (ad_sigma_delta_has_spi_offload(sigma_delta)) {
+ sigma_delta->offload_trigger =
+ devm_spi_offload_trigger_get(dev, sigma_delta->offload,
+ SPI_OFFLOAD_TRIGGER_DATA_READY);
+ if (IS_ERR(sigma_delta->offload_trigger))
+ return dev_err_probe(dev, PTR_ERR(sigma_delta->offload_trigger),
+ "Failed to get SPI offload trigger\n");
+ } else {
+ if (dev != &sigma_delta->spi->dev)
+ return dev_err_probe(dev, -EFAULT,
+ "Trigger parent should be '%s', got '%s'\n",
+ dev_name(dev), dev_name(&sigma_delta->spi->dev));
- ret = devm_iio_trigger_register(dev, sigma_delta->trig);
- if (ret)
- return ret;
+ sigma_delta->trig = devm_iio_trigger_alloc(dev, "%s-dev%d",
+ indio_dev->name, iio_device_id(indio_dev));
+ if (!sigma_delta->trig)
+ return -ENOMEM;
+
+ iio_trigger_set_drvdata(sigma_delta->trig, sigma_delta);
+
+ ret = devm_iio_trigger_register(dev, sigma_delta->trig);
+ if (ret)
+ return ret;
- /* select default trigger */
- indio_dev->trig = iio_trigger_get(sigma_delta->trig);
+ /* select default trigger */
+ indio_dev->trig = iio_trigger_get(sigma_delta->trig);
+ }
return 0;
}
@@ -628,16 +808,33 @@ int devm_ad_sd_setup_buffer_and_trigger(struct device *dev, struct iio_dev *indi
if (!sigma_delta->slots)
return -ENOMEM;
- ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
- &iio_pollfunc_store_time,
- &ad_sd_trigger_handler,
- &ad_sd_buffer_setup_ops);
- if (ret)
- return ret;
+ if (ad_sigma_delta_has_spi_offload(sigma_delta)) {
+ struct dma_chan *rx_dma;
+
+ rx_dma = devm_spi_offload_rx_stream_request_dma_chan(dev,
+ sigma_delta->offload);
+ if (IS_ERR(rx_dma))
+ return dev_err_probe(dev, PTR_ERR(rx_dma),
+ "Failed to get RX DMA channel\n");
+
+ ret = devm_iio_dmaengine_buffer_setup_with_handle(dev, indio_dev,
+ rx_dma, IIO_BUFFER_DIRECTION_IN);
+ if (ret)
+ return dev_err_probe(dev, ret, "Cannot setup DMA buffer\n");
+
+ indio_dev->setup_ops = &ad_sd_buffer_setup_ops;
+ } else {
+ ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
+ &iio_pollfunc_store_time,
+ &ad_sd_trigger_handler,
+ &ad_sd_buffer_setup_ops);
+ if (ret)
+ return ret;
+ }
return devm_ad_sd_probe_trigger(dev, indio_dev);
}
-EXPORT_SYMBOL_NS_GPL(devm_ad_sd_setup_buffer_and_trigger, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(devm_ad_sd_setup_buffer_and_trigger, "IIO_AD_SIGMA_DELTA");
/**
* ad_sd_init() - Initializes a ad_sigma_delta struct
@@ -655,7 +852,7 @@ int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev,
sigma_delta->spi = spi;
sigma_delta->info = info;
- /* If the field is unset in ad_sigma_delta_info, asume there can only be 1 slot. */
+ /* If the field is unset in ad_sigma_delta_info, assume there can only be 1 slot. */
if (!info->num_slots)
sigma_delta->num_slots = 1;
else
@@ -673,17 +870,50 @@ int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev,
}
}
- if (info->irq_line)
- sigma_delta->irq_line = info->irq_line;
- else
+ spin_lock_init(&sigma_delta->irq_lock);
+
+ if (info->has_named_irqs) {
+ sigma_delta->irq_line = fwnode_irq_get_byname(dev_fwnode(&spi->dev),
+ "rdy");
+ if (sigma_delta->irq_line < 0)
+ return dev_err_probe(&spi->dev, sigma_delta->irq_line,
+ "Interrupt 'rdy' is required\n");
+ } else {
sigma_delta->irq_line = spi->irq;
+ }
+
+ sigma_delta->rdy_gpiod = devm_gpiod_get_optional(&spi->dev, "rdy", GPIOD_IN);
+ if (IS_ERR(sigma_delta->rdy_gpiod))
+ return dev_err_probe(&spi->dev, PTR_ERR(sigma_delta->rdy_gpiod),
+ "Failed to find rdy gpio\n");
+
+ if (sigma_delta->rdy_gpiod && !sigma_delta->irq_line) {
+ sigma_delta->irq_line = gpiod_to_irq(sigma_delta->rdy_gpiod);
+ if (sigma_delta->irq_line < 0)
+ return sigma_delta->irq_line;
+ }
+
+ if (info->supports_spi_offload) {
+ struct spi_offload_config offload_config = {
+ .capability_flags = SPI_OFFLOAD_CAP_TRIGGER |
+ SPI_OFFLOAD_CAP_RX_STREAM_DMA,
+ };
+ int ret;
+
+ sigma_delta->offload = devm_spi_offload_get(&spi->dev, spi,
+ &offload_config);
+ ret = PTR_ERR_OR_ZERO(sigma_delta->offload);
+ if (ret && ret != -ENODEV)
+ return dev_err_probe(&spi->dev, ret, "Failed to get SPI offload\n");
+ }
iio_device_set_drvdata(indio_dev, sigma_delta);
return 0;
}
-EXPORT_SYMBOL_NS_GPL(ad_sd_init, IIO_AD_SIGMA_DELTA);
+EXPORT_SYMBOL_NS_GPL(ad_sd_init, "IIO_AD_SIGMA_DELTA");
MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>");
MODULE_DESCRIPTION("Analog Devices Sigma-Delta ADCs");
MODULE_LICENSE("GPL v2");
+MODULE_IMPORT_NS("IIO_DMAENGINE_BUFFER");