Merge tag 'staging-4.17-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging

Pull IIO driver fixes from Greg KH:
 "Here are some old IIO driver fixes that were sitting in my tree for a
  few weeks. Sorry about not getting them to you sooner. They fix a
  number of small IIO driver issues that have been reported.

  All of these have been in linux-next for a while with no reported
  problems"

* tag 'staging-4.17-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging:
  iio: adc: select buffer for at91-sama5d2_adc
  iio: hid-sensor-trigger: Fix sometimes not powering up the sensor after resume
  iio: adc: at91-sama5d2_adc: fix channel configuration for differential channels
  iio:kfifo_buf: check for uint overflow
  iio:buffer: make length types match kfifo types
  iio: adc: stm32-dfsdm: fix sample rate for div2 spi clock
  iio: adc: stm32-dfsdm: fix successive oversampling settings
  iio: ad7793: implement IIO_CHAN_INFO_SAMP_FREQ

8 files changed, 93 insertions, 68 deletions

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 15606f237480..9da79070357c 100644
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -158,6 +158,7 @@ config AT91_SAMA5D2_ADC
 	depends on ARCH_AT91 || COMPILE_TEST
 	depends on HAS_IOMEM
 	depends on HAS_DMA
+	select IIO_BUFFER
 	select IIO_TRIGGERED_BUFFER
 	help
 	  Say yes here to build support for Atmel SAMA5D2 ADC which is
diff --git a/drivers/iio/adc/ad7793.c b/drivers/iio/adc/ad7793.c
index 801afb61310b..d4bbe5b53318 100644
--- a/drivers/iio/adc/ad7793.c
+++ b/drivers/iio/adc/ad7793.c
@@ -348,55 +348,6 @@ static const u16 ad7793_sample_freq_avail[16] = {0, 470, 242, 123, 62, 50, 39,
 static const u16 ad7797_sample_freq_avail[16] = {0, 0, 0, 123, 62, 50, 0,
 					33, 0, 17, 16, 12, 10, 8, 6, 4};
 
-static ssize_t ad7793_read_frequency(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct ad7793_state *st = iio_priv(indio_dev);
-
-	return sprintf(buf, "%d\n",
-	       st->chip_info->sample_freq_avail[AD7793_MODE_RATE(st->mode)]);
-}
-
-static ssize_t ad7793_write_frequency(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *indio_dev = dev_to_iio_dev(dev);
-	struct ad7793_state *st = iio_priv(indio_dev);
-	long lval;
-	int i, ret;
-
-	ret = kstrtol(buf, 10, &lval);
-	if (ret)
-		return ret;
-
-	if (lval == 0)
-		return -EINVAL;
-
-	for (i = 0; i < 16; i++)
-		if (lval == st->chip_info->sample_freq_avail[i])
-			break;
-	if (i == 16)
-		return -EINVAL;
-
-	ret = iio_device_claim_direct_mode(indio_dev);
-	if (ret)
-		return ret;
-	st->mode &= ~AD7793_MODE_RATE(-1);
-	st->mode |= AD7793_MODE_RATE(i);
-	ad_sd_write_reg(&st->sd, AD7793_REG_MODE, sizeof(st->mode), st->mode);
-	iio_device_release_direct_mode(indio_dev);
-
-	return len;
-}
-
-static IIO_DEV_ATTR_SAMP_FREQ(S_IWUSR | S_IRUGO,
-		ad7793_read_frequency,
-		ad7793_write_frequency);
-
 static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
 	"470 242 123 62 50 39 33 19 17 16 12 10 8 6 4");
 
@@ -424,7 +375,6 @@ static IIO_DEVICE_ATTR_NAMED(in_m_in_scale_available,
 		ad7793_show_scale_available, NULL, 0);
 
 static struct attribute *ad7793_attributes[] = {
-	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	&iio_const_attr_sampling_frequency_available.dev_attr.attr,
 	&iio_dev_attr_in_m_in_scale_available.dev_attr.attr,
 	NULL
@@ -435,7 +385,6 @@ static const struct attribute_group ad7793_attribute_group = {
 };
 
 static struct attribute *ad7797_attributes[] = {
-	&iio_dev_attr_sampling_frequency.dev_attr.attr,
 	&iio_const_attr_sampling_frequency_available_ad7797.dev_attr.attr,
 	NULL
 };
@@ -505,6 +454,10 @@ static int ad7793_read_raw(struct iio_dev *indio_dev,
 			*val -= offset;
 		}
 		return IIO_VAL_INT;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		*val = st->chip_info
+			       ->sample_freq_avail[AD7793_MODE_RATE(st->mode)];
+		return IIO_VAL_INT;
 	}
 	return -EINVAL;
 }
@@ -542,6 +495,26 @@ static int ad7793_write_raw(struct iio_dev *indio_dev,
 				break;
 			}
 		break;
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		if (!val) {
+			ret = -EINVAL;
+			break;
+		}
+
+		for (i = 0; i < 16; i++)
+			if (val == st->chip_info->sample_freq_avail[i])
+				break;
+
+		if (i == 16) {
+			ret = -EINVAL;
+			break;
+		}
+
+		st->mode &= ~AD7793_MODE_RATE(-1);
+		st->mode |= AD7793_MODE_RATE(i);
+		ad_sd_write_reg(&st->sd, AD7793_REG_MODE, sizeof(st->mode),
+				st->mode);
+		break;
 	default:
 		ret = -EINVAL;
 	}
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 4eff8351ce29..8729d6524b4d 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -333,6 +333,27 @@ static const struct iio_chan_spec at91_adc_channels[] = {
 				+ AT91_SAMA5D2_DIFF_CHAN_CNT + 1),
 };
 
+static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan)
+{
+	int i;
+
+	for (i = 0; i < indio_dev->num_channels; i++) {
+		if (indio_dev->channels[i].scan_index == chan)
+			return i;
+	}
+	return -EINVAL;
+}
+
+static inline struct iio_chan_spec const *
+at91_adc_chan_get(struct iio_dev *indio_dev, int chan)
+{
+	int index = at91_adc_chan_xlate(indio_dev, chan);
+
+	if (index < 0)
+		return NULL;
+	return indio_dev->channels + index;
+}
+
 static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
 {
 	struct iio_dev *indio = iio_trigger_get_drvdata(trig);
@@ -350,8 +371,10 @@ static int at91_adc_configure_trigger(struct iio_trigger *trig, bool state)
 	at91_adc_writel(st, AT91_SAMA5D2_TRGR, status);
 
 	for_each_set_bit(bit, indio->active_scan_mask, indio->num_channels) {
-		struct iio_chan_spec const *chan = indio->channels + bit;
+		struct iio_chan_spec const *chan = at91_adc_chan_get(indio, bit);
 
+		if (!chan)
+			continue;
 		if (state) {
 			at91_adc_writel(st, AT91_SAMA5D2_CHER,
 					BIT(chan->channel));
@@ -448,7 +471,11 @@ static int at91_adc_dma_start(struct iio_dev *indio_dev)
 
 	for_each_set_bit(bit, indio_dev->active_scan_mask,
 			 indio_dev->num_channels) {
-		struct iio_chan_spec const *chan = indio_dev->channels + bit;
+		struct iio_chan_spec const *chan =
+					 at91_adc_chan_get(indio_dev, bit);
+
+		if (!chan)
+			continue;
 
 		st->dma_st.rx_buf_sz += chan->scan_type.storagebits / 8;
 	}
@@ -526,8 +553,11 @@ static int at91_adc_buffer_predisable(struct iio_dev *indio_dev)
 	 */
 	for_each_set_bit(bit, indio_dev->active_scan_mask,
 			 indio_dev->num_channels) {
-		struct iio_chan_spec const *chan = indio_dev->channels + bit;
+		struct iio_chan_spec const *chan =
+					at91_adc_chan_get(indio_dev, bit);
 
+		if (!chan)
+			continue;
 		if (st->dma_st.dma_chan)
 			at91_adc_readl(st, chan->address);
 	}
@@ -587,8 +617,11 @@ static void at91_adc_trigger_handler_nodma(struct iio_dev *indio_dev,
 
 	for_each_set_bit(bit, indio_dev->active_scan_mask,
 			 indio_dev->num_channels) {
-		struct iio_chan_spec const *chan = indio_dev->channels + bit;
+		struct iio_chan_spec const *chan =
+					at91_adc_chan_get(indio_dev, bit);
 
+		if (!chan)
+			continue;
 		st->buffer[i] = at91_adc_readl(st, chan->address);
 		i++;
 	}
diff --git a/drivers/iio/adc/stm32-dfsdm-adc.c b/drivers/iio/adc/stm32-dfsdm-adc.c
index 01422d11753c..b28a716a23b2 100644
--- a/drivers/iio/adc/stm32-dfsdm-adc.c
+++ b/drivers/iio/adc/stm32-dfsdm-adc.c
@@ -144,6 +144,7 @@ static int stm32_dfsdm_set_osrs(struct stm32_dfsdm_filter *fl,
 	 * Leave as soon as if exact resolution if reached.
 	 * Otherwise the higher resolution below 32 bits is kept.
 	 */
+	fl->res = 0;
 	for (fosr = 1; fosr <= DFSDM_MAX_FL_OVERSAMPLING; fosr++) {
 		for (iosr = 1; iosr <= DFSDM_MAX_INT_OVERSAMPLING; iosr++) {
 			if (fast)
@@ -193,7 +194,7 @@ static int stm32_dfsdm_set_osrs(struct stm32_dfsdm_filter *fl,
 		}
 	}
 
-	if (!fl->fosr)
+	if (!fl->res)
 		return -EINVAL;
 
 	return 0;
@@ -770,7 +771,7 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev,
 	struct stm32_dfsdm_adc *adc = iio_priv(indio_dev);
 	struct stm32_dfsdm_filter *fl = &adc->dfsdm->fl_list[adc->fl_id];
 	struct stm32_dfsdm_channel *ch = &adc->dfsdm->ch_list[chan->channel];
-	unsigned int spi_freq = adc->spi_freq;
+	unsigned int spi_freq;
 	int ret = -EINVAL;
 
 	switch (mask) {
@@ -784,8 +785,18 @@ static int stm32_dfsdm_write_raw(struct iio_dev *indio_dev,
 	case IIO_CHAN_INFO_SAMP_FREQ:
 		if (!val)
 			return -EINVAL;
-		if (ch->src != DFSDM_CHANNEL_SPI_CLOCK_EXTERNAL)
+
+		switch (ch->src) {
+		case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL:
 			spi_freq = adc->dfsdm->spi_master_freq;
+			break;
+		case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_FALLING:
+		case DFSDM_CHANNEL_SPI_CLOCK_INTERNAL_DIV2_RISING:
+			spi_freq = adc->dfsdm->spi_master_freq / 2;
+			break;
+		default:
+			spi_freq = adc->spi_freq;
+		}
 
 		if (spi_freq % val)
 			dev_warn(&indio_dev->dev,
diff --git a/drivers/iio/buffer/industrialio-buffer-dma.c b/drivers/iio/buffer/industrialio-buffer-dma.c
index 05e0c353e089..b32bf57910ca 100644
--- a/drivers/iio/buffer/industrialio-buffer-dma.c
+++ b/drivers/iio/buffer/industrialio-buffer-dma.c
@@ -587,7 +587,7 @@ EXPORT_SYMBOL_GPL(iio_dma_buffer_set_bytes_per_datum);
  * Should be used as the set_length callback for iio_buffer_access_ops
  * struct for DMA buffers.
  */
-int iio_dma_buffer_set_length(struct iio_buffer *buffer, int length)
+int iio_dma_buffer_set_length(struct iio_buffer *buffer, unsigned int length)
 {
 	/* Avoid an invalid state */
 	if (length < 2)
diff --git a/drivers/iio/buffer/kfifo_buf.c b/drivers/iio/buffer/kfifo_buf.c
index 047fe757ab97..70c302a93d7f 100644
--- a/drivers/iio/buffer/kfifo_buf.c
+++ b/drivers/iio/buffer/kfifo_buf.c
@@ -22,11 +22,18 @@ struct iio_kfifo {
 #define iio_to_kfifo(r) container_of(r, struct iio_kfifo, buffer)
 
 static inline int __iio_allocate_kfifo(struct iio_kfifo *buf,
-				int bytes_per_datum, int length)
+			size_t bytes_per_datum, unsigned int length)
 {
 	if ((length == 0) || (bytes_per_datum == 0))
 		return -EINVAL;
 
+	/*
+	 * Make sure we don't overflow an unsigned int after kfifo rounds up to
+	 * the next power of 2.
+	 */
+	if (roundup_pow_of_two(length) > UINT_MAX / bytes_per_datum)
+		return -EINVAL;
+
 	return __kfifo_alloc((struct __kfifo *)&buf->kf, length,
 			     bytes_per_datum, GFP_KERNEL);
 }
@@ -67,7 +74,7 @@ static int iio_set_bytes_per_datum_kfifo(struct iio_buffer *r, size_t bpd)
 	return 0;
 }
 
-static int iio_set_length_kfifo(struct iio_buffer *r, int length)
+static int iio_set_length_kfifo(struct iio_buffer *r, unsigned int length)
 {
 	/* Avoid an invalid state */
 	if (length < 2)
diff --git a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
index cfb6588565ba..4905a997a7ec 100644
--- a/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
+++ b/drivers/iio/common/hid-sensors/hid-sensor-trigger.c
@@ -178,14 +178,14 @@ int hid_sensor_power_state(struct hid_sensor_common *st, bool state)
 #ifdef CONFIG_PM
 	int ret;
 
-	atomic_set(&st->user_requested_state, state);
-
 	if (atomic_add_unless(&st->runtime_pm_enable, 1, 1))
 		pm_runtime_enable(&st->pdev->dev);
 
-	if (state)
+	if (state) {
+		atomic_inc(&st->user_requested_state);
 		ret = pm_runtime_get_sync(&st->pdev->dev);
-	else {
+	} else {
+		atomic_dec(&st->user_requested_state);
 		pm_runtime_mark_last_busy(&st->pdev->dev);
 		pm_runtime_use_autosuspend(&st->pdev->dev);
 		ret = pm_runtime_put_autosuspend(&st->pdev->dev);
diff --git a/include/linux/iio/buffer_impl.h b/include/linux/iio/buffer_impl.h
index b9e22b7e2f28..d1171db23742 100644
--- a/include/linux/iio/buffer_impl.h
+++ b/include/linux/iio/buffer_impl.h
@@ -53,7 +53,7 @@ struct iio_buffer_access_funcs {
 	int (*request_update)(struct iio_buffer *buffer);
 
 	int (*set_bytes_per_datum)(struct iio_buffer *buffer, size_t bpd);
-	int (*set_length)(struct iio_buffer *buffer, int length);
+	int (*set_length)(struct iio_buffer *buffer, unsigned int length);
 
 	int (*enable)(struct iio_buffer *buffer, struct iio_dev *indio_dev);
 	int (*disable)(struct iio_buffer *buffer, struct iio_dev *indio_dev);
@@ -72,10 +72,10 @@ struct iio_buffer_access_funcs {
  */
 struct iio_buffer {
 	/** @length: Number of datums in buffer. */
-	int length;
+	unsigned int length;
 
 	/**  @bytes_per_datum: Size of individual datum including timestamp. */
-	int bytes_per_datum;
+	size_t bytes_per_datum;
 
 	/**
 	 * @access: Buffer access functions associated with the