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DLN2 module for ADC interface

PATCH New Jack Andersen 3 participants 4 messages Jun 22, 2017

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#0 lore raw

PATCH 1/1 DLN2 module for ADC interface

Hello,

I've been having to blacklist the dln2 module in order to use Diolan's iffy libusb-based "driver". I'd much rather use dln2, but the lack of ADC support has been an issue for my robotics application.

I've extended the dln2 module with an additional platform driver to expose the ADC using the IIO subsystem. It supports triggered buffering via the event handle kept by dln2, as well as direct raw reads. The voltage scale is fixed at 3.3v over 10-bits, since that appears to be the maximum resolution supported by the hardware.

I've tested the module under 4.11.6 and everything appears to be stable. However, this is my first patch, so it's possible I've missed something.

Jack Andersen (1):
iio: adc: Add support for DLN2 ADC

 drivers/iio/adc/Kconfig    |   9 +
 drivers/iio/adc/Makefile   |   1 +
 drivers/iio/adc/dln2-adc.c | 648 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/mfd/dln2.c         |  12 +
 4 files changed, 670 insertions(+)
 create mode 100644 drivers/iio/adc/dln2-adc.c
Signature · 1 line
1.9.1
#1 lore raw

PATCH 1/1 iio: adc: Add support for DLN2 ADC

This patch adds support for Diolan DLN2 ADC via IIO's ADC interface. ADC is the fourth and final component of the DLN2 for the kernel.

---
 drivers/iio/adc/Kconfig    |   9 +
 drivers/iio/adc/Makefile   |   1 +
 drivers/iio/adc/dln2-adc.c | 648 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/mfd/dln2.c         |  12 +
 4 files changed, 670 insertions(+)
 create mode 100644 drivers/iio/adc/dln2-adc.c
drivers/iio/adc/Kconfig +9 -0
index 401f47b..78d7455 100644
@@ -239,6 +239,15 @@ config DA9150_GPADC
 	  To compile this driver as a module, choose M here: the module will be
 	  called berlin2-adc.
 
+config DLN2_ADC
+	tristate "Diolan DLN-2 ADC driver support"
+	depends on MFD_DLN2
+	help
+	  Say yes here to build support for Diolan DLN-2 ADC.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called adc_dln2.
+
 config ENVELOPE_DETECTOR
 	tristate "Envelope detector using a DAC and a comparator"
 	depends on OF
drivers/iio/adc/Makefile +1 -0
index 9339bec..378bc65 100644
@@ -24,6 +24,7 @@ obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
 obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
 obj-$(CONFIG_CPCAP_ADC) += cpcap-adc.o
 obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
+obj-$(CONFIG_DLN2_ADC) += dln2-adc.o
 obj-$(CONFIG_ENVELOPE_DETECTOR) += envelope-detector.o
 obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
 obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
drivers/iio/adc/dln2-adc.c new file +648 -0

648 lines not on this page · raw message

drivers/mfd/dln2.c +12 -0
index 704e189..a22ab8c 100644
@@ -53,6 +53,7 @@ enum dln2_handle {
 	DLN2_HANDLE_GPIO,
 	DLN2_HANDLE_I2C,
 	DLN2_HANDLE_SPI,
+	DLN2_HANDLE_ADC,
 	DLN2_HANDLES
 };
 
@@ -663,6 +664,12 @@ static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
 	.port = 0,
 };
 
+/* Only one ADC port supported */
+static struct dln2_platform_data dln2_pdata_adc = {
+	.handle = DLN2_HANDLE_ADC,
+	.port = 0,
+};
+
 static const struct mfd_cell dln2_devs[] = {
 	{
 		.name = "dln2-gpio",
@@ -679,6 +686,11 @@ static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
 		.platform_data = &dln2_pdata_spi,
 		.pdata_size = sizeof(struct dln2_platform_data),
 	},
+	{
+		.name = "dln2-adc",
+		.platform_data = &dln2_pdata_adc,
+		.pdata_size = sizeof(struct dln2_platform_data),
+	},
 };
 
 static void dln2_stop(struct dln2_dev *dln2)
Signature · 1 line
1.9.1
#2 lore raw

Re: [PATCH] iio: adc: Add support for DLN2 ADC

Quoted 3 lines

This patch adds support for Diolan DLN2 ADC via IIO's ADC interface. ADC is the fourth and final component of the DLN2 for the kernel.

comments below

Quoted 60 lines
---
 drivers/iio/adc/Kconfig    |   9 +
 drivers/iio/adc/Makefile   |   1 +
 drivers/iio/adc/dln2-adc.c | 648 +++++++++++++++++++++++++++++++++++++++++++++
 drivers/mfd/dln2.c         |  12 +
 4 files changed, 670 insertions(+)
 create mode 100644 drivers/iio/adc/dln2-adc.c
drivers/iio/adc/Kconfig +9 -0
index 401f47b..78d7455 100644
@@ -239,6 +239,15 @@ config DA9150_GPADC
 	  To compile this driver as a module, choose M here: the module will be
 	  called berlin2-adc.
 
+config DLN2_ADC
+	tristate "Diolan DLN-2 ADC driver support"
+	depends on MFD_DLN2
+	help
+	  Say yes here to build support for Diolan DLN-2 ADC.
+
+	  This driver can also be built as a module. If so, the module will be
+	  called adc_dln2.
+
 config ENVELOPE_DETECTOR
 	tristate "Envelope detector using a DAC and a comparator"
 	depends on OF
drivers/iio/adc/Makefile +1 -0
index 9339bec..378bc65 100644
@@ -24,6 +24,7 @@ obj-$(CONFIG_BERLIN2_ADC) += berlin2-adc.o
 obj-$(CONFIG_CC10001_ADC) += cc10001_adc.o
 obj-$(CONFIG_CPCAP_ADC) += cpcap-adc.o
 obj-$(CONFIG_DA9150_GPADC) += da9150-gpadc.o
+obj-$(CONFIG_DLN2_ADC) += dln2-adc.o
 obj-$(CONFIG_ENVELOPE_DETECTOR) += envelope-detector.o
 obj-$(CONFIG_EXYNOS_ADC) += exynos_adc.o
 obj-$(CONFIG_FSL_MX25_ADC) += fsl-imx25-gcq.o
drivers/iio/adc/dln2-adc.c new file +13 -0
new file mode 100644
index 0000000..7900e2c
@@ -0,0 +1,648 @@
+/*
+ * Driver for the Diolan DLN-2 USB-ADC adapter
+ *
+ * Copyright (c) 2017 Jack Andersen
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation, version 2.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>

drivers/iio/adc/dln2-adc.c line 23

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+#include <linux/platform_device.h>
+#include <linux/mfd/dln2.h>
+
+#include <linux/iio/iio.h>
+#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/trigger_consumer.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/virtio.h>

virtio needed?

Quoted 21 lines
drivers/iio/adc/dln2-adc.c new file +21 -0
+#include <linux/version.h>
+
+#define DLN2_ADC_MOD_NAME "dln2-adc"
+
+#define DLN2_ADC_ID             0x06
+
+#define DLN2_ADC_GET_CHANNEL_COUNT	DLN2_CMD(0x01, DLN2_ADC_ID)
+#define DLN2_ADC_ENABLE			DLN2_CMD(0x02, DLN2_ADC_ID)
+#define DLN2_ADC_DISABLE		DLN2_CMD(0x03, DLN2_ADC_ID)
+#define DLN2_ADC_CHANNEL_ENABLE		DLN2_CMD(0x05, DLN2_ADC_ID)
+#define DLN2_ADC_CHANNEL_DISABLE	DLN2_CMD(0x06, DLN2_ADC_ID)
+#define DLN2_ADC_SET_RESOLUTION		DLN2_CMD(0x08, DLN2_ADC_ID)
+#define DLN2_ADC_CHANNEL_GET_VAL	DLN2_CMD(0x0A, DLN2_ADC_ID)
+#define DLN2_ADC_CHANNEL_GET_ALL_VAL	DLN2_CMD(0x0B, DLN2_ADC_ID)
+#define DLN2_ADC_CHANNEL_SET_CFG	DLN2_CMD(0x0C, DLN2_ADC_ID)
+#define DLN2_ADC_CHANNEL_GET_CFG	DLN2_CMD(0x0D, DLN2_ADC_ID)
+#define DLN2_ADC_CONDITION_MET_EV	DLN2_CMD(0x10, DLN2_ADC_ID)
+
+#define DLN2_ADC_EVENT_NONE		0
+#define DLN2_ADC_EVENT_BELOW		1
+#define DLN2_ADC_EVENT_LEVEL_ABOVE	2

drivers/iio/adc/dln2-adc.c line 54

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+#define DLN2_ADC_EVENT_OUTSIDE		3
+#define DLN2_ADC_EVENT_INSIDE		4
+#define DLN2_ADC_EVENT_ALWAYS		5
+
+#define DLN2_ADC_MAX_CHANNELS 8
+#define DLN2_ADC_DATA_BITS 10
+
+struct dln2_adc {
+	struct platform_device *pdev;
+	int port;

u8

drivers/iio/adc/dln2-adc.c line 57

Quoted 3 lines
drivers/iio/adc/dln2-adc.c new file +3 -0
+	struct iio_trigger *trig;
+	/* Set once initialized */
+	u8 port_enabled;

bool, and use true/false

drivers/iio/adc/dln2-adc.c line 59

Quoted 2 lines
drivers/iio/adc/dln2-adc.c new file +2 -0
+	/* Set once resolution request made to HW */
+	u8 resolution_set;

bool

Quoted 13 lines
drivers/iio/adc/dln2-adc.c new file +13 -0
+	/* Bitmask requesting enabled channels */
+	unsigned long chans_requested;
+	/* Bitmask indicating enabled channels on HW */
+	unsigned long chans_enabled;
+	/* Channel that is arbitrated for event trigger */
+	int trigger_chan;
+};
+
+struct dln2_adc_port_chan {
+	u8 port;
+	u8 chan;
+};
+

drivers/iio/adc/dln2-adc.c line 82

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+struct dln2_adc_get_all_vals {
+	__le16 channel_mask;
+	__le16 values[DLN2_ADC_MAX_CHANNELS];
+};
+
+static int dln2_adc_get_chan_count(struct dln2_adc *dln2)
+{
+	int ret;
+	u8 port = dln2->port;
+	int ilen = sizeof(port);

save/drop these two temporary variable (here and elsewhere)

Quoted 13 lines
drivers/iio/adc/dln2-adc.c new file +13 -0
+	u8 count;
+	int olen = sizeof(count);
+
+	ret = dln2_transfer(dln2->pdev, DLN2_ADC_GET_CHANNEL_COUNT,
+			    &port, ilen, &count, &olen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+		return ret;
+	}
+	if (olen < sizeof(count))
+		return -EPROTO;
+
+	return count;

drivers/iio/adc/dln2-adc.c line 105

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+}
+
+static int dln2_adc_set_port_resolution(struct dln2_adc *dln2)
+{
+	int ret;
+	struct dln2_adc_port_chan port_chan = {
+		.port = dln2->port,
+		.chan = DLN2_ADC_DATA_BITS,
+	};
+	int ilen = sizeof(port_chan);

save/drop temporary variable, here and elsewhere

Quoted 79 lines
drivers/iio/adc/dln2-adc.c new file +79 -0
+
+	ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_SET_RESOLUTION,
+			       &port_chan, ilen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int dln2_adc_set_chan_enabled(struct dln2_adc *dln2,
+				     int channel, bool enable)
+{
+	int ret;
+	struct dln2_adc_port_chan port_chan = {
+		.port = dln2->port,
+		.chan = channel,
+	};
+	int ilen = sizeof(port_chan);
+
+	u16 cmd = enable ? DLN2_ADC_CHANNEL_ENABLE : DLN2_ADC_CHANNEL_DISABLE;
+
+	ret = dln2_transfer_tx(dln2->pdev, cmd, &port_chan, ilen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int dln2_adc_set_port_enabled(struct dln2_adc *dln2, bool enable)
+{
+	int ret;
+	u8 port = dln2->port;
+	int ilen = sizeof(port);
+	__le16 conflict;
+	int olen = sizeof(conflict);
+
+	u16 cmd = enable ? DLN2_ADC_ENABLE : DLN2_ADC_DISABLE;
+
+	ret = dln2_transfer(dln2->pdev, cmd, &port, ilen, &conflict, &olen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s(%d)\n",
+			__func__, (int)enable);
+		return ret;
+	}
+	if (enable && olen < sizeof(conflict))
+		return -EPROTO;
+
+	return 0;
+}
+
+/*
+ * ADC channels are lazily enabled due to the pins being shared with GPIO
+ * channels. Enabling channels requires taking the ADC port offline, specifying
+ * the resolution, individually enabling channels, then putting the port back
+ * online. If GPIO pins have already been exported by gpio_dln2, EINVAL is
+ * reported.
+ */
+static int dln2_adc_update_enabled_chans(struct dln2_adc *dln2)
+{
+	int ret, i, chan_count;
+	struct iio_dev *indio_dev;
+
+	if (dln2->chans_enabled == dln2->chans_requested)
+		return 0;
+
+	indio_dev = platform_get_drvdata(dln2->pdev);
+	chan_count = indio_dev->num_channels;
+
+	if (dln2->port_enabled) {
+		ret = dln2_adc_set_port_enabled(dln2, false);
+		if (ret < 0)
+			return ret;
+		dln2->port_enabled = false;
+	}
+

drivers/iio/adc/dln2-adc.c line 194

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	if (!dln2->resolution_set) {
+		ret = dln2_adc_set_port_resolution(dln2);
+		if (ret < 0)
+			return ret;
+		dln2->resolution_set = true;
+	}
+
+	for (i = 0; i < chan_count; ++i) {
+		bool requested = (dln2->chans_requested & (1 << i));
+		bool enabled = (dln2->chans_enabled & (1 << i));

outer parenthesis not needed

Quoted 34 lines
drivers/iio/adc/dln2-adc.c new file +34 -0
+
+		if (requested == enabled)
+			continue;
+		ret = dln2_adc_set_chan_enabled(dln2, i, requested);
+		if (ret < 0)
+			return ret;
+	}
+
+	dln2->chans_enabled = dln2->chans_requested;
+
+	ret = dln2_adc_set_port_enabled(dln2, true);
+	if (ret < 0)
+		return ret;
+	dln2->port_enabled = true;
+
+	return ret;
+}
+
+static int dln2_adc_get_chan_freq(struct dln2_adc *dln2, unsigned int channel)
+{
+	int ret;
+	struct dln2_adc_port_chan port_chan = {
+		.port = dln2->port,
+		.chan = channel,
+	};
+	int ilen = sizeof(port_chan);
+	struct {
+		__u8 type;
+		__le16 period;
+		__le16 low;
+		__le16 high;
+	} __packed get_cfg;
+	int olen = sizeof(get_cfg);
+

drivers/iio/adc/dln2-adc.c line 238

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_CFG,
+			    &port_chan, ilen, &get_cfg, &olen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+		return ret;
+	}
+	if (olen < sizeof(get_cfg))
+		return -EPROTO;
+
+	return get_cfg.period;

period is __le16, need to use le16_to_cpu()

Quoted 7 lines
drivers/iio/adc/dln2-adc.c new file +7 -0
+}
+
+static int dln2_adc_set_chan_freq(struct dln2_adc *dln2, unsigned int channel,
+				  unsigned int freq)
+{
+	int ret;
+	struct {

drivers/iio/adc/dln2-adc.c line 255

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+		struct dln2_adc_port_chan port_chan;
+		__u8 type;
+		__le16 period;
+		__le16 low;
+		__le16 high;
+	} __packed set_cfg = {
+		.port_chan.port = dln2->port,
+		.port_chan.chan = channel,
+		.type = freq ? DLN2_ADC_EVENT_ALWAYS : DLN2_ADC_EVENT_NONE,
+		.period = freq

end with ,
use cpu_to_le16() on freq

drivers/iio/adc/dln2-adc.c line 259

Quoted 4 lines
drivers/iio/adc/dln2-adc.c new file +4 -0
+	};
+
+	ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_CHANNEL_SET_CFG,
+			       &set_cfg, sizeof(set_cfg));

no dev_dbg() here?

drivers/iio/adc/dln2-adc.c line 271

Quoted 12 lines
drivers/iio/adc/dln2-adc.c new file +12 -0
+	return ret;
+}
+
+static int dln2_adc_read(struct dln2_adc *dln2, unsigned int channel)
+{
+	int ret;
+
+	dln2->chans_requested |= (1 << channel);
+	ret = dln2_adc_update_enabled_chans(dln2);
+	if (ret < 0)
+		return ret;
+	dln2->port_enabled = 1;

need to rollback chans_requested?

Quoted 17 lines
drivers/iio/adc/dln2-adc.c new file +17 -0
+
+	struct dln2_adc_port_chan port_chan = {
+		.port = dln2->port,
+		.chan = channel,
+	};
+	int ilen = sizeof(port_chan);
+	__le16 value;
+	int olen = sizeof(value);
+
+	ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_VAL,
+			    &port_chan, ilen, &value, &olen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+		return ret;
+	}
+	if (olen < sizeof(value))
+		return -EPROTO;

drivers/iio/adc/dln2-adc.c line 298

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+
+	return le16_to_cpu(value);
+}
+
+static int dln2_adc_read_all(struct dln2_adc *dln2,
+			     struct dln2_adc_get_all_vals *get_all_vals)
+{
+	int ret;
+	__u8 port = dln2->port;
+	int olen = sizeof(struct dln2_adc_get_all_vals);

why not
sizeof(dln2_adc_get_all_vals)
as done with other structs?

Quoted 15 lines
drivers/iio/adc/dln2-adc.c new file +15 -0
+
+	ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_ALL_VAL,
+			    &port, sizeof(port), get_all_vals, &olen);
+	if (ret < 0) {
+		dev_dbg(&dln2->pdev->dev, "Problem in %s\n", __func__);
+		return ret;
+	}
+	if (olen < sizeof(struct dln2_adc_get_all_vals))
+		return -EPROTO;
+
+	return 0;
+}
+
+static int dln2_adc_read_raw(struct iio_dev *indio_dev,
+			     struct iio_chan_spec const *chan,

drivers/iio/adc/dln2-adc.c line 323

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+			     int *val,
+			     int *val2,
+			     long mask)
+{
+	int ret;
+	struct dln2_adc *dln2 = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		mutex_lock(&indio_dev->mlock);

use your own lock as most/all other drivers do, here and elsewhere

drivers/iio/adc/dln2-adc.c line 335

Quoted 12 lines
drivers/iio/adc/dln2-adc.c new file +12 -0
+		ret = dln2_adc_read(dln2, chan->channel);
+		mutex_unlock(&indio_dev->mlock);
+
+		if (ret < 0)
+			break;
+
+		*val = ret;
+		return IIO_VAL_INT;
+
+	case IIO_CHAN_INFO_SCALE:
+		*val = 0;
+		// 3.3 / (1 << 10) * 1000000;

no C++ style comments

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+		*val2 = 3222656;
+		return IIO_VAL_INT_PLUS_NANO;
+
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		mutex_lock(&indio_dev->mlock);
+		if (dln2->trigger_chan == -1)
+			ret = 0;
+		else
+			ret = dln2_adc_get_chan_freq(dln2, dln2->trigger_chan);
+		mutex_unlock(&indio_dev->mlock);

drivers/iio/adc/dln2-adc.c line 355

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+
+		if (ret < 0)
+			break;
+
+		*val = ret / 1000;
+		*val2 = (ret % 1000) * 1000;
+		return IIO_VAL_INT_PLUS_MICRO;
+
+	default:
+		break;

return -EINVAL directly here and elsewhere

drivers/iio/adc/dln2-adc.c line 367

Quoted 12 lines
drivers/iio/adc/dln2-adc.c new file +12 -0
+	}
+
+	return -EINVAL;
+}
+
+static int dln2_adc_write_raw(struct iio_dev *indio_dev,
+			      struct iio_chan_spec const *chan,
+			      int val,
+			      int val2,
+			      long mask)
+{
+	int ret = 0;

initialization not needed

Quoted 40 lines
drivers/iio/adc/dln2-adc.c new file +40 -0
+	unsigned int freq;
+	struct dln2_adc *dln2 = iio_priv(indio_dev);
+
+	switch (mask) {
+	case IIO_CHAN_INFO_SAMP_FREQ:
+		freq = val * 1000 + val2 / 1000;
+		if (freq > 65535) {
+			freq = 65535;
+			dev_warn(&dln2->pdev->dev,
+				 "clamping freq to 65535ms\n");
+		}
+		mutex_lock(&indio_dev->mlock);
+
+		/*
+		 * The first requested channel is arbitrated as a shared
+		 * trigger source, so only one event is registered with the DLN.
+		 * The event handler will then read all enabled channel values
+		 * using DLN2_ADC_CHANNEL_GET_ALL_VAL to maintain
+		 * synchronization between ADC readings.
+		 */
+		if (dln2->trigger_chan == -1)
+			dln2->trigger_chan = chan->channel;
+		ret = dln2_adc_set_chan_freq(dln2, dln2->trigger_chan, freq);
+
+		mutex_unlock(&indio_dev->mlock);
+
+		if (ret < 0)
+			break;
+
+		return 0;
+
+	default:
+		break;
+	}
+
+	return -EINVAL;
+}
+
+#define DLN2_ADC_CHAN(idx) {					\
+	.type = IIO_VOLTAGE,					\

drivers/iio/adc/dln2-adc.c line 417

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	.indexed = 1,						\
+	.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),		\
+	.info_mask_shared_by_all = BIT(IIO_CHAN_INFO_SCALE) |	\
+				   BIT(IIO_CHAN_INFO_SAMP_FREQ),\
+	.scan_type.sign = 'u',					\
+	.scan_type.realbits = DLN2_ADC_DATA_BITS,		\
+	.scan_type.storagebits = 16,				\
+	.scan_type.endianness = IIO_LE,				\
+	.channel = idx,						\
+	.scan_index = idx,					\

maybe move .scan_index next to .scan_type and .channel next to .indexed

Quoted 5 lines
drivers/iio/adc/dln2-adc.c new file +5 -0
+}
+
+static const struct iio_chan_spec dln2_adc_iio_channels[] = {
+	DLN2_ADC_CHAN(0),
+	DLN2_ADC_CHAN(1),

drivers/iio/adc/dln2-adc.c line 432

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	DLN2_ADC_CHAN(2),
+	DLN2_ADC_CHAN(3),
+	DLN2_ADC_CHAN(4),
+	DLN2_ADC_CHAN(5),
+	DLN2_ADC_CHAN(6),
+	DLN2_ADC_CHAN(7),
+};
+
+static const struct iio_info dln2_adc_info = {
+	.read_raw = &dln2_adc_read_raw,

no need for & for functions

drivers/iio/adc/dln2-adc.c line 442

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	.write_raw = &dln2_adc_write_raw,
+	.driver_module = THIS_MODULE,
+};
+
+static irqreturn_t dln2_adc_trigger_h(int irq, void *p)
+{
+	struct iio_poll_func *pf = p;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	int len = 0;
+	u16 *data;

__le16

Quoted 9 lines
drivers/iio/adc/dln2-adc.c new file +9 -0
+	struct dln2_adc_get_all_vals dev_data;
+	struct dln2_adc *dln2 = iio_priv(indio_dev);
+
+	mutex_lock(&indio_dev->mlock);
+
+	dln2->chans_requested |= *indio_dev->active_scan_mask;
+	if (dln2_adc_update_enabled_chans(dln2) < 0) {
+		mutex_unlock(&indio_dev->mlock);
+		goto done;

drivers/iio/adc/dln2-adc.c line 461

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	}
+
+	if (dln2_adc_read_all(dln2, &dev_data) < 0) {
+		mutex_unlock(&indio_dev->mlock);
+		goto done;
+	}
+
+	mutex_unlock(&indio_dev->mlock);
+
+	data = kmalloc(indio_dev->scan_bytes, GFP_KERNEL);

maybe statically allocate maximum size in struct dln2_adc (or on stack) and use that

drivers/iio/adc/dln2-adc.c line 466

Quoted 5 lines
drivers/iio/adc/dln2-adc.c new file +5 -0
+	if (!data)
+		goto done;
+
+	if (!bitmap_empty(indio_dev->active_scan_mask,
+			  indio_dev->masklength)) {

is this check needed? can't we just loop over and find that no bit is set?

drivers/iio/adc/dln2-adc.c line 476

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+		int i, j;
+
+		for (i = 0, j = 0;
+		     i < bitmap_weight(indio_dev->active_scan_mask,
+				       indio_dev->masklength);
+		     i++, j++) {
+			j = find_next_bit(indio_dev->active_scan_mask,
+					  indio_dev->masklength, j);
+			data[i] = dev_data.values[j];
+			len += 2;

2 should be sizeof(__le16) or sizeof(dev_data.values[i])

drivers/iio/adc/dln2-adc.c line 481

Quoted 5 lines
drivers/iio/adc/dln2-adc.c new file +5 -0
+		}
+	}
+
+	iio_push_to_buffers_with_timestamp(indio_dev, data,
+					   iio_get_time_ns(indio_dev));

there is no timestamp in dln2_adc_iio_channels; data would need space for timestamp + packing

Quoted 4 lines
drivers/iio/adc/dln2-adc.c new file +4 -0
+
+	kfree(data);
+
+done:

drivers/iio/adc/dln2-adc.c line 495

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+	iio_trigger_notify_done(indio_dev->trig);
+	return IRQ_HANDLED;
+}
+
+static int dln2_adc_triggered_buffer_postenable(struct iio_dev *indio_dev)
+{
+	struct dln2_adc *dln2 = iio_priv(indio_dev);
+
+	dln2->chans_requested |= *indio_dev->active_scan_mask;
+	dln2_adc_update_enabled_chans(dln2);

check return value?

drivers/iio/adc/dln2-adc.c line 502

Quoted 7 lines
drivers/iio/adc/dln2-adc.c new file +7 -0
+
+	return iio_triggered_buffer_postenable(indio_dev);
+}
+
+static const struct iio_buffer_setup_ops dln2_adc_buffer_setup_ops = {
+	.postenable = &dln2_adc_triggered_buffer_postenable,
+	.predisable = &iio_triggered_buffer_predisable,

no need for &

Quoted 11 lines
drivers/iio/adc/dln2-adc.c new file +11 -0
+};
+
+static void dln2_adc_event(struct platform_device *pdev, u16 echo,
+			   const void *data, int len)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct dln2_adc *dln2 = iio_priv(indio_dev);
+
+	iio_trigger_poll(dln2->trig);
+}
+

drivers/iio/adc/dln2-adc.c line 523

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+static const struct iio_trigger_ops dln2_adc_trigger_ops = {
+	.owner = THIS_MODULE,
+};
+
+static int dln2_adc_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct dln2_adc *dln2;
+	struct dln2_platform_data *pdata = dev_get_platdata(&pdev->dev);
+	struct iio_dev *indio_dev = NULL;

no need to initialize

drivers/iio/adc/dln2-adc.c line 525

Quoted 2 lines
drivers/iio/adc/dln2-adc.c new file +2 -0
+	struct iio_buffer *buffer;
+	int ret = -ENODEV;

no need to initialize

drivers/iio/adc/dln2-adc.c line 537

Quoted 12 lines
drivers/iio/adc/dln2-adc.c new file +12 -0
+	int chans;
+
+	indio_dev = devm_iio_device_alloc(dev, sizeof(struct dln2_adc));
+	if (!indio_dev) {
+		dev_err(dev, "failed allocating iio device\n");
+		return -ENOMEM;
+	}
+
+	dln2 = iio_priv(indio_dev);
+	dln2->pdev = pdev;
+	dln2->port = pdata->port;
+	dln2->port_enabled = 0;

false

drivers/iio/adc/dln2-adc.c line 538

Quoted 1 line
drivers/iio/adc/dln2-adc.c new file +1 -0
+	dln2->resolution_set = 0;

false

Quoted 60 lines
drivers/iio/adc/dln2-adc.c new file +60 -0
+	dln2->chans_requested = 0;
+	dln2->chans_enabled = 0;
+	dln2->trigger_chan = -1;
+
+	platform_set_drvdata(pdev, indio_dev);
+
+	chans = dln2_adc_get_chan_count(dln2);
+	if (chans < 0) {
+		dev_err(dev, "failed to get channel count: %d\n", chans);
+		ret = chans;
+		goto dealloc_dev;
+	}
+	if (chans > DLN2_ADC_MAX_CHANNELS) {
+		chans = DLN2_ADC_MAX_CHANNELS;
+		dev_warn(dev, "clamping channels to %d\n",
+			 DLN2_ADC_MAX_CHANNELS);
+	}
+
+	indio_dev->name = DLN2_ADC_MOD_NAME;
+	indio_dev->dev.parent = dev;
+	indio_dev->info = &dln2_adc_info;
+	indio_dev->modes = INDIO_DIRECT_MODE | INDIO_BUFFER_TRIGGERED;
+	indio_dev->channels = dln2_adc_iio_channels;
+	indio_dev->num_channels = chans;
+	indio_dev->setup_ops = &dln2_adc_buffer_setup_ops;
+
+	dln2->trig = devm_iio_trigger_alloc(dev, "samplerate");
+	if (!dln2->trig) {
+		dev_err(dev, "failed to allocate trigger\n");
+		goto dealloc_dev;
+	}
+	dln2->trig->ops = &dln2_adc_trigger_ops;
+	iio_trigger_set_drvdata(dln2->trig, dln2);
+	iio_trigger_register(dln2->trig);
+	iio_trigger_set_immutable(indio_dev, dln2->trig);
+
+	buffer = devm_iio_kfifo_allocate(dev);
+	if (!buffer) {
+		dev_err(dev, "failed to allocate kfifo\n");
+		ret = -ENOMEM;
+		goto dealloc_trigger;
+	}
+
+	iio_device_attach_buffer(indio_dev, buffer);
+
+	indio_dev->pollfunc = iio_alloc_pollfunc(NULL,
+						 &dln2_adc_trigger_h,
+						 IRQF_ONESHOT,
+						 indio_dev,
+						 "samplerate");
+
+	if (!indio_dev->pollfunc) {
+		ret = -ENOMEM;
+		goto dealloc_kfifo;
+	}
+
+	ret = dln2_register_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV,
+				     dln2_adc_event);
+	if (ret) {
+		dev_err(dev, "failed to register event cb: %d\n", ret);

drivers/iio/adc/dln2-adc.c line 608

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+		goto dealloc_pollfunc;
+	}
+
+	ret = iio_device_register(indio_dev);
+	if (ret) {
+		dev_err(dev, "failed to register iio device: %d\n", ret);
+		goto dealloc_pollfunc;
+	}
+
+	dev_info(dev, "DLN2 ADC driver loaded\n");

avoid this kind of logging

Quoted 9 lines
drivers/iio/adc/dln2-adc.c new file +9 -0
+
+	return 0;
+
+dealloc_pollfunc:
+	iio_dealloc_pollfunc(indio_dev->pollfunc);
+dealloc_kfifo:
+dealloc_trigger:
+	iio_trigger_unregister(dln2->trig);
+dealloc_dev:

drivers/iio/adc/dln2-adc.c line 627

Quoted 10 lines
drivers/iio/adc/dln2-adc.c new file +10 -0
+
+	return ret;
+}
+
+static int dln2_adc_remove(struct platform_device *pdev)
+{
+	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+	struct dln2_adc *dln2 = iio_priv(indio_dev);
+
+	dev_info(&indio_dev->dev, "DLN2 ADC driver unloaded\n");

no such logging please

drivers/iio/adc/dln2-adc.c line 629

Quoted 2 lines
drivers/iio/adc/dln2-adc.c new file +2 -0
+
+	dln2_unregister_event_cb(pdev, DLN2_ADC_CONDITION_MET_EV);

should be after device_unregister

Quoted 57 lines
drivers/iio/adc/dln2-adc.c new file +19 -0
+	iio_device_unregister(indio_dev);
+	iio_trigger_unregister(dln2->trig);
+	iio_dealloc_pollfunc(indio_dev->pollfunc);
+
+	return 0;
+}
+
+static struct platform_driver dln2_adc_driver = {
+	.driver.name	= DLN2_ADC_MOD_NAME,
+	.probe		= dln2_adc_probe,
+	.remove		= dln2_adc_remove,
+};
+
+module_platform_driver(dln2_adc_driver);
+
+MODULE_AUTHOR("Jack Andersen <[email protected]");
+MODULE_DESCRIPTION("Driver for the Diolan DLN2 ADC interface");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:dln2-adc");
drivers/mfd/dln2.c +12 -0
index 704e189..a22ab8c 100644
@@ -53,6 +53,7 @@ enum dln2_handle {
 	DLN2_HANDLE_GPIO,
 	DLN2_HANDLE_I2C,
 	DLN2_HANDLE_SPI,
+	DLN2_HANDLE_ADC,
 	DLN2_HANDLES
 };
 
@@ -663,6 +664,12 @@ static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
 	.port = 0,
 };
 
+/* Only one ADC port supported */
+static struct dln2_platform_data dln2_pdata_adc = {
+	.handle = DLN2_HANDLE_ADC,
+	.port = 0,
+};
+
 static const struct mfd_cell dln2_devs[] = {
 	{
 		.name = "dln2-gpio",
@@ -679,6 +686,11 @@ static int dln2_start_rx_urbs(struct dln2_dev *dln2, gfp_t gfp)
 		.platform_data = &dln2_pdata_spi,
 		.pdata_size = sizeof(struct dln2_platform_data),
 	},
+	{
+		.name = "dln2-adc",
+		.platform_data = &dln2_pdata_adc,
+		.pdata_size = sizeof(struct dln2_platform_data),
+	},
 };
 
 static void dln2_stop(struct dln2_dev *dln2)
Signature · 2 lines
Peter Meerwald-Stadler
Mobile: +43 664 24 44 418
#3 lore raw

Re: [PATCH] iio: adc: Add support for DLN2 ADC

In reply to Jack Andersen
reproduce: wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree make.cross…

Hi Jack,

[auto build test WARNING on iio/togreg]
[also build test WARNING on v4.12-rc6 next-20170622]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Jack-Andersen/iio-adc-Add-support-for-DLN2-ADC/20170623-055246
base:   https://git.kernel.org/pub/scm/linux/kernel/git/jic23/iio.git togreg
config: blackfin-allyesconfig (attached as .config)
compiler: bfin-uclinux-gcc (GCC) 6.2.0

reproduce:
wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
make.cross ARCH=blackfin

All warnings (new ones prefixed by >>):

drivers/iio/adc/dln2-adc.c: In function 'dln2_adc_read':

>> drivers/iio/adc/dln2-adc.c:273:2: warning: ISO C90 forbids mixed declarations and code [-Wdeclaration-after-statement]
     struct dln2_adc_port_chan port_chan = {
     ^~~~~~

vim +273 drivers/iio/adc/dln2-adc.c

257
258 ret = dln2_transfer_tx(dln2->pdev, DLN2_ADC_CHANNEL_SET_CFG,
259 &set_cfg, sizeof(set_cfg));
260 return ret;
261 }
262
263 static int dln2_adc_read(struct dln2_adc *dln2, unsigned int channel)
264 {
265 int ret;
266
267 dln2->chans_requested |= (1 << channel);
268 ret = dln2_adc_update_enabled_chans(dln2);
269 if (ret < 0)
270 return ret;
271 dln2->port_enabled = 1;
272

 > 273		struct dln2_adc_port_chan port_chan = {

274 .port = dln2->port,
275 .chan = channel,
276 };
277 int ilen = sizeof(port_chan);
278 __le16 value;
279 int olen = sizeof(value);
280
281 ret = dln2_transfer(dln2->pdev, DLN2_ADC_CHANNEL_GET_VAL,

---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all Intel Corporation