[PATCH v3 0/3] Add support for DLH pressure sensors

[PATCH v3 0/3] Add support for DLH pressure sensors

[tomislav.denis]

From: Tomislav Denis <tomislav.denis@avl.com>

This patchset adds support for All Sensors DLH series low
voltage digital pressure sensors.

Datasheet: https://www.allsensors.com/cad/DS-0355_Rev_B.PDF

Changes in v3:
- missing ack included in the commit message
- unneceseary iio_buffer_enabled check removed
- data ready trigger removed
- trigger handler and read raw functions refactored

Changes in v2:
- web page link in the MAINTAINERS file fixed
- adjust the units of the output to the IIO ABI
- unneceseary default case removed
- define the channel member of the iio_chan_spec
  struct for channels specification
- remove explicit cast for pointers of type void *
- add support for the EOC(data ready) pin
- drop the unneceseary return ret;
- rename dlh-i2c.yaml to asc,dlh-i2c.yaml
- change the bindings copyright to GPL-2.0-only OR BSD-2-Clause
- document EOC(data ready) pin

Tomislav Denis (3):
  iio: pressure: Add driver for DLH pressure sensors
  dt-bindings: Add asc vendor
  bindings: iio: pressure: Add dlh-i2c documentation

 .../bindings/iio/pressure/asc,dlh-i2c.yaml         |  51 +++
 .../devicetree/bindings/vendor-prefixes.yaml       |   2 +
 MAINTAINERS                                        |   8 +
 drivers/iio/pressure/Kconfig                       |  12 +
 drivers/iio/pressure/Makefile                      |   1 +
 drivers/iio/pressure/dlh-i2c.c                     | 375 +++++++++++++++++++++
 6 files changed, 449 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
 create mode 100644 drivers/iio/pressure/dlh-i2c.c

-- 
2.7.4

[PATCH v3 1/3] iio: pressure: Add driver for DLH pressure sensors

[tomislav.denis]

From: Tomislav Denis <tomislav.denis@avl.com>

All Sensors DLH is series of low voltage digital pressure sensors.
Additionally to pressure value sensors deliver a temperature value.
Sensors can be accessed over I2C and SPI, this driver supports
only I2C access.

Signed-off-by: Tomislav Denis <tomislav.denis@avl.com>
---
 MAINTAINERS                    |   7 +
 drivers/iio/pressure/Kconfig   |  12 ++
 drivers/iio/pressure/Makefile  |   1 +
 drivers/iio/pressure/dlh-i2c.c | 375 +++++++++++++++++++++++++++++++++++++++++
 4 files changed, 395 insertions(+)
 create mode 100644 drivers/iio/pressure/dlh-i2c.c

diff --git a/MAINTAINERS b/MAINTAINERS
index d5ea4e4..39d6f0f 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -668,6 +668,13 @@ S:	Maintained
 F:	Documentation/i2c/busses/i2c-ali1563.rst
 F:	drivers/i2c/busses/i2c-ali1563.c
 
+ALL SENSORS DLH SERIES PRESSURE SENSORS DRIVER
+M:	Tomislav Denis <tomislav.denis@avl.com>
+W:	http://www.allsensors.com/
+S:	Maintained
+L:	linux-iio@vger.kernel.org
+F:	drivers/iio/pressure/dlh-i2c.c
+
 ALLEGRO DVT VIDEO IP CORE DRIVER
 M:	Michael Tretter <m.tretter@pengutronix.de>
 R:	Pengutronix Kernel Team <kernel@pengutronix.de>
diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig
index ba420e4..504de3e 100644
--- a/drivers/iio/pressure/Kconfig
+++ b/drivers/iio/pressure/Kconfig
@@ -53,6 +53,18 @@ config IIO_CROS_EC_BARO
 	  To compile this driver as a module, choose M here: the module
 	  will be called cros_ec_baro.
 
+config DLH_I2C
+	tristate "All Sensors DLH series low voltage digital pressure sensors"
+	depends on I2C
+	select IIO_BUFFER
+	select IIO_TRIGGERED_BUFFER
+	help
+	  Say yes here to build support for the All Sensors DLH series
+	  pressure sensors driver.
+
+	  To compile this driver as a module, choose M here: the module
+	  will be called dlh-i2c.
+
 config DPS310
 	tristate "Infineon DPS310 pressure and temperature sensor"
 	depends on I2C
diff --git a/drivers/iio/pressure/Makefile b/drivers/iio/pressure/Makefile
index d8f5ace..1851a36 100644
--- a/drivers/iio/pressure/Makefile
+++ b/drivers/iio/pressure/Makefile
@@ -9,6 +9,7 @@ obj-$(CONFIG_BMP280) += bmp280.o
 bmp280-objs := bmp280-core.o bmp280-regmap.o
 obj-$(CONFIG_BMP280_I2C) += bmp280-i2c.o
 obj-$(CONFIG_BMP280_SPI) += bmp280-spi.o
+obj-$(CONFIG_DLH_I2C) += dlh-i2c.o
 obj-$(CONFIG_DPS310) += dps310.o
 obj-$(CONFIG_IIO_CROS_EC_BARO) += cros_ec_baro.o
 obj-$(CONFIG_HID_SENSOR_PRESS)   += hid-sensor-press.o
diff --git a/drivers/iio/pressure/dlh-i2c.c b/drivers/iio/pressure/dlh-i2c.c
new file mode 100644
index 0000000..b8491a8
--- /dev/null
+++ b/drivers/iio/pressure/dlh-i2c.c
@@ -0,0 +1,375 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * All Sensors DLH series low voltage digital pressure sensors
+ *
+ * Copyright (c) 2019 AVL DiTEST GmbH
+ *   Tomislav Denis <tomislav.denis@avl.com>
+ *
+ * Datasheet: http://www.allsensors.com/cad/DS-0355_Rev_B.PDF
+ */
+
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/i2c.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>
+
+/* Commands */
+#define DLH_START_SINGLE    0xAA
+
+/* Status bits */
+#define DLH_STATUS_OK       0x40
+
+/* DLH  data format */
+#define DLH_NUM_READ_BYTES  7
+#define DLH_NUM_DATA_BYTES  3
+#define DLH_NUM_PR_BITS     24
+#define DLH_NUM_TEMP_BITS   24
+
+/* DLH  timings */
+#define DLH_SINGLE_DUT_MS   5
+
+enum dhl_ids {
+	dlhl60d,
+	dlhl60g,
+};
+
+struct dlh_info {
+	u8 osdig;           /* digital offset factor */
+	unsigned int fss;   /* full scale span (inch H2O) */
+};
+
+struct dlh_state {
+	struct i2c_client *client;
+	struct dlh_info info;
+	bool use_interrupt;
+	struct completion completion;
+	u8 rx_buf[DLH_NUM_READ_BYTES] ____cacheline_aligned;
+};
+
+static struct dlh_info dlh_info_tbl[] = {
+	[dlhl60d] = {
+		.osdig = 2,
+		.fss = 120,
+	},
+	[dlhl60g] = {
+		.osdig = 10,
+		.fss = 60,
+	},
+};
+
+
+static int dlh_i2c_cmd_start_single(struct dlh_state *st)
+{
+	int ret;
+
+	ret = i2c_smbus_write_byte(st->client, DLH_START_SINGLE);
+	if (ret)
+		dev_err(&st->client->dev,
+			"%s: I2C write byte failed\n", __func__);
+
+	return ret;
+}
+
+static int dlh_i2c_cmd_read_data(struct dlh_state *st)
+{
+	int ret;
+
+	ret = i2c_master_recv(st->client, st->rx_buf, DLH_NUM_READ_BYTES);
+	if (ret < 0) {
+		dev_err(&st->client->dev,
+			"%s: I2C read block failed\n", __func__);
+		return ret;
+	}
+
+	if (st->rx_buf[0] != DLH_STATUS_OK) {
+		dev_err(&st->client->dev,
+			"%s: invalid status 0x%02x\n", __func__, st->rx_buf[0]);
+		return -EBUSY;
+	}
+
+	return 0;
+}
+
+static int dlh_i2c_start_capture_and_read(struct dlh_state *st)
+{
+	int ret;
+
+	if (st->use_interrupt)
+		reinit_completion(&st->completion);
+
+	ret = dlh_i2c_cmd_start_single(st);
+	if (ret)
+		return ret;
+
+	if (st->use_interrupt) {
+		ret = wait_for_completion_timeout(&st->completion,
+			msecs_to_jiffies(DLH_SINGLE_DUT_MS));
+		if (!ret) {
+			dev_err(&st->client->dev,
+				"%s: conversion timed out\n", __func__);
+			return -ETIMEDOUT;
+		}
+	} else {
+		mdelay(DLH_SINGLE_DUT_MS);
+	}
+
+	return dlh_i2c_cmd_read_data(st);
+}
+
+static int dlh_i2c_read_direct(struct dlh_state *st,
+	unsigned int *pressure, unsigned int *temperature)
+{
+	int ret;
+
+	ret = dlh_i2c_start_capture_and_read(st);
+	if (ret)
+		return ret;
+
+	*pressure = be32_to_cpup((u32 *)&st->rx_buf[1]) >> 8;
+	*temperature = be32_to_cpup((u32 *)&st->rx_buf[3]) &
+		GENMASK(DLH_NUM_TEMP_BITS - 1, 0);
+
+	return 0;
+}
+
+static int dlh_i2c_read_raw(struct iio_dev *indio_dev,
+	struct iio_chan_spec const *channel, int *value,
+	int *value2, long mask)
+{
+	struct dlh_state *st = iio_priv(indio_dev);
+	unsigned int pressure, temperature;
+	int ret;
+	s64 tmp;
+	s32 rem;
+
+	switch (mask) {
+	case IIO_CHAN_INFO_RAW:
+		ret = iio_device_claim_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+
+		ret = dlh_i2c_read_direct(st, &pressure, &temperature);
+		iio_device_release_direct_mode(indio_dev);
+		if (ret)
+			return ret;
+
+		switch (channel->type) {
+		case IIO_PRESSURE:
+			*value = pressure;
+			return IIO_VAL_INT;
+
+		case IIO_TEMP:
+			*value = temperature;
+			return IIO_VAL_INT;
+
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_SCALE:
+		switch (channel->type) {
+		case IIO_PRESSURE:
+			tmp = div_s64(125LL * st->info.fss * 24909 * 100,
+				1 << DLH_NUM_PR_BITS);
+			tmp = div_s64_rem(tmp, 1000000000LL, &rem);
+			*value = tmp;
+			*value2 = rem;
+			return IIO_VAL_INT_PLUS_NANO;
+
+		case IIO_TEMP:
+			*value = 125 * 1000;
+			*value2 = DLH_NUM_TEMP_BITS;
+			return IIO_VAL_FRACTIONAL_LOG2;
+
+		default:
+			return -EINVAL;
+		}
+	case IIO_CHAN_INFO_OFFSET:
+		switch (channel->type) {
+		case IIO_PRESSURE:
+			*value = -125 * st->info.fss * 24909;
+			*value2 = 100 * st->info.osdig * 100000;
+			return IIO_VAL_FRACTIONAL;
+
+		case IIO_TEMP:
+			*value = -40 * 1000;
+			return IIO_VAL_INT;
+
+		default:
+			return -EINVAL;
+		}
+	}
+
+	return -EINVAL;
+}
+
+static const struct iio_info dlh_i2c_info = {
+	.read_raw = dlh_i2c_read_raw,
+};
+
+static const struct iio_chan_spec dlh_i2c_channels[] = {
+	{
+		.type = IIO_PRESSURE,
+		.indexed = 1,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type =
+			BIT(IIO_CHAN_INFO_SCALE) |
+			BIT(IIO_CHAN_INFO_OFFSET),
+		.scan_index = 0,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = DLH_NUM_PR_BITS,
+			.storagebits = 32,
+			.shift = 8,
+			.endianness = IIO_BE,
+		},
+	}, {
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
+		.info_mask_shared_by_type =
+			BIT(IIO_CHAN_INFO_SCALE) |
+			BIT(IIO_CHAN_INFO_OFFSET),
+		.scan_index = 1,
+		.scan_type = {
+			.sign = 'u',
+			.realbits = DLH_NUM_TEMP_BITS,
+			.storagebits = 32,
+			.shift = 8,
+			.endianness = IIO_BE,
+		},
+	}
+};
+
+static irqreturn_t dlh_i2c_trigger_handler(int irq, void *private)
+{
+	struct iio_poll_func *pf = private;
+	struct iio_dev *indio_dev = pf->indio_dev;
+	struct dlh_state *st = iio_priv(indio_dev);
+	int ret;
+	unsigned int chn, i = 0;
+	__be32 tmp_buf[2];
+
+	ret = dlh_i2c_start_capture_and_read(st);
+	if (ret)
+		goto out;
+
+	for_each_set_bit(chn, indio_dev->active_scan_mask,
+		indio_dev->masklength) {
+		memcpy(tmp_buf + i,
+			&st->rx_buf[1] + chn * DLH_NUM_DATA_BYTES,
+			DLH_NUM_DATA_BYTES);
+		i++;
+	}
+
+	iio_push_to_buffers(indio_dev, tmp_buf);
+
+out:
+	iio_trigger_notify_done(indio_dev->trig);
+
+	return IRQ_HANDLED;
+}
+
+static irqreturn_t dlh_i2c_interrupt(int irq, void *private)
+{
+	struct iio_dev *indio_dev = private;
+	struct dlh_state *st = iio_priv(indio_dev);
+
+	complete(&st->completion);
+
+	return IRQ_HANDLED;
+};
+
+static int dlh_i2c_probe(struct i2c_client *client,
+	const struct i2c_device_id *id)
+{
+	struct dlh_state *st;
+	struct iio_dev *indio_dev;
+	int ret;
+
+	if (!i2c_check_functionality(client->adapter,
+		I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE)) {
+		dev_err(&client->dev,
+			"adapter doesn't support required i2c functionality\n");
+		return -EOPNOTSUPP;
+	}
+
+	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
+	if (!indio_dev) {
+		dev_err(&client->dev, "failed to allocate iio device\n");
+		return -ENOMEM;
+	}
+
+	i2c_set_clientdata(client, indio_dev);
+
+	st = iio_priv(indio_dev);
+	st->info = dlh_info_tbl[id->driver_data];
+	st->client = client;
+	st->use_interrupt = false;
+
+	indio_dev->name = id->name;
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->dev.of_node = client->dev.of_node;
+	indio_dev->info = &dlh_i2c_info;
+	indio_dev->modes = INDIO_DIRECT_MODE;
+	indio_dev->channels =  dlh_i2c_channels;
+	indio_dev->num_channels = ARRAY_SIZE(dlh_i2c_channels);
+
+	if (client->irq > 0) {
+		ret = devm_request_threaded_irq(&client->dev, client->irq,
+			dlh_i2c_interrupt, NULL,
+			IRQF_TRIGGER_RISING | IRQF_ONESHOT,
+			id->name, indio_dev);
+		if (ret) {
+			dev_err(&client->dev, "failed to allocate threaded irq");
+			return ret;
+		}
+
+		st->use_interrupt = true;
+		init_completion(&st->completion);
+	}
+
+	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
+		NULL, &dlh_i2c_trigger_handler, NULL);
+	if (ret) {
+		dev_err(&client->dev, "failed to setup iio buffer\n");
+		return ret;
+	}
+
+	ret = devm_iio_device_register(&client->dev, indio_dev);
+	if (ret)
+		dev_err(&client->dev, "failed to register iio device\n");
+
+	return ret;
+}
+
+static const struct of_device_id dlh_i2c_of_match[] = {
+	{ .compatible = "asc,dlhl60d" },
+	{ .compatible = "asc,dlhl60g" },
+	{}
+};
+MODULE_DEVICE_TABLE(of, dlh_i2c_of_match);
+
+static const struct i2c_device_id dlh_i2c_id[] = {
+	{ "dlhl60d",    dlhl60d },
+	{ "dlhl60g",    dlhl60g },
+	{}
+};
+MODULE_DEVICE_TABLE(i2c, dlh_i2c_id);
+
+static struct i2c_driver dlh_i2c_driver = {
+	.driver = {
+		.name = "dlh_i2c",
+		.of_match_table = dlh_i2c_of_match,
+	},
+	.probe = dlh_i2c_probe,
+	.id_table = dlh_i2c_id,
+};
+module_i2c_driver(dlh_i2c_driver);
+
+MODULE_AUTHOR("Tomislav Denis <tomislav.denis@avl.com>");
+MODULE_DESCRIPTION("Driver for All Sensors DLH series pressure sensors");
+MODULE_LICENSE("GPL v2");
-- 
2.7.4

[PATCH v3 2/3] dt-bindings: Add asc vendor

[tomislav.denis]

From: Tomislav Denis <tomislav.denis@avl.com>

All Sensors Corporation is a manufacturer of MEMS piezoresitive
ultra low pressure sensors and pressure transducers.

Signed-off-by: Tomislav Denis <tomislav.denis@avl.com>
Acked-by: Rob Herring <robh@kernel.org>
---
 Documentation/devicetree/bindings/vendor-prefixes.yaml | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 967e78c..88247b3 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -109,6 +109,8 @@ patternProperties:
     description: Artesyn Embedded Technologies Inc.
   "^asahi-kasei,.*":
     description: Asahi Kasei Corp.
+  "^asc,.*":
+    description: All Sensors Corporation
   "^aspeed,.*":
     description: ASPEED Technology Inc.
   "^asus,.*":
-- 
2.7.4

[PATCH v3 3/3] bindings: iio: pressure: Add dlh-i2c documentation

[tomislav.denis]

From: Tomislav Denis <tomislav.denis@avl.com>

Add a device tree binding documentation for DLH series pressure
sensors.

Signed-off-by: Tomislav Denis <tomislav.denis@avl.com>
---
 .../bindings/iio/pressure/asc,dlh-i2c.yaml         | 51 ++++++++++++++++++++++
 MAINTAINERS                                        |  1 +
 2 files changed, 52 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml

diff --git a/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml b/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
new file mode 100644
index 0000000..5de2277
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
@@ -0,0 +1,51 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/iio/pressure/dlh-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: All Sensors DLH series low voltage digital pressure sensors
+
+maintainers:
+  - Tomislav Denis <tomislav.denis@avl.com>
+
+description: |
+  Bindings for the All Sensors DLH series pressure sensors.
+
+  Specifications about the sensors can be found at:
+    http://www.allsensors.com/cad/DS-0355_Rev_B.PDF
+
+properties:
+  compatible:
+    enum:
+      - asc,dlhl60d
+      - asc,dlhl60g
+
+  reg:
+    description: I2C device address
+    maxItems: 1
+
+  interrupts:
+    description: interrupt mapping for EOC(data ready) pin
+    maxItems: 1
+
+required:
+  - compatible
+  - reg
+
+examples:
+  - |
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    i2c0 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+
+      pressure@29 {
+          compatible = "asc,dlhl60d";
+          reg = <0x29>;
+          interrupt-parent = <&gpio0>;
+          interrupts = <10 IRQ_TYPE_EDGE_RISING>;
+      };
+    };
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index 39d6f0f..8f0eab0 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -674,6 +674,7 @@ W:	http://www.allsensors.com/
 S:	Maintained
 L:	linux-iio@vger.kernel.org
 F:	drivers/iio/pressure/dlh-i2c.c
+F:	Documentation/devicetree/bindings/iio/pressure/dlh-i2c.yaml
 
 ALLEGRO DVT VIDEO IP CORE DRIVER
 M:	Michael Tretter <m.tretter@pengutronix.de>
-- 
2.7.4

Re: [PATCH v3 3/3] bindings: iio: pressure: Add dlh-i2c documentation

[Jonathan Cameron]

On Wed, 4 Dec 2019 11:03:54 +0100
<tomislav.denis@avl.com> wrote:

> From: Tomislav Denis <tomislav.denis@avl.com>
> 
> Add a device tree binding documentation for DLH series pressure
> sensors.
> 
> Signed-off-by: Tomislav Denis <tomislav.denis@avl.com>

One question for DT maintainers.  

Should the file be named after a specific part of is a generic
name for the parts covered acceptable?  I would assume it should
be a part number, but not sure what precedence there is.

Otherwise looks good to me, but I will let it sit to give time
for DT review.

Thanks,

Jonathan

> ---
>  .../bindings/iio/pressure/asc,dlh-i2c.yaml         | 51 ++++++++++++++++++++++
>  MAINTAINERS                                        |  1 +
>  2 files changed, 52 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
> 
> diff --git a/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml b/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
> new file mode 100644
> index 0000000..5de2277
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/iio/pressure/dlh-i2c.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: All Sensors DLH series low voltage digital pressure sensors
> +
> +maintainers:
> +  - Tomislav Denis <tomislav.denis@avl.com>
> +
> +description: |
> +  Bindings for the All Sensors DLH series pressure sensors.
> +
> +  Specifications about the sensors can be found at:
> +    http://www.allsensors.com/cad/DS-0355_Rev_B.PDF
> +
> +properties:
> +  compatible:
> +    enum:
> +      - asc,dlhl60d
> +      - asc,dlhl60g
> +
> +  reg:
> +    description: I2C device address
> +    maxItems: 1
> +
> +  interrupts:
> +    description: interrupt mapping for EOC(data ready) pin
> +    maxItems: 1
> +
> +required:
> +  - compatible
> +  - reg
> +
> +examples:
> +  - |
> +    #include <dt-bindings/interrupt-controller/irq.h>
> +
> +    i2c0 {
> +      #address-cells = <1>;
> +      #size-cells = <0>;
> +
> +      pressure@29 {
> +          compatible = "asc,dlhl60d";
> +          reg = <0x29>;
> +          interrupt-parent = <&gpio0>;
> +          interrupts = <10 IRQ_TYPE_EDGE_RISING>;
> +      };
> +    };
> +...
> diff --git a/MAINTAINERS b/MAINTAINERS
> index 39d6f0f..8f0eab0 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -674,6 +674,7 @@ W:	http://www.allsensors.com/
>  S:	Maintained
>  L:	linux-iio@vger.kernel.org
>  F:	drivers/iio/pressure/dlh-i2c.c
> +F:	Documentation/devicetree/bindings/iio/pressure/dlh-i2c.yaml
>  
>  ALLEGRO DVT VIDEO IP CORE DRIVER
>  M:	Michael Tretter <m.tretter@pengutronix.de>

Re: [PATCH v3 1/3] iio: pressure: Add driver for DLH pressure sensors

[Jonathan Cameron]

On Wed, 4 Dec 2019 11:03:52 +0100
<tomislav.denis@avl.com> wrote:

> From: Tomislav Denis <tomislav.denis@avl.com>
> 
> All Sensors DLH is series of low voltage digital pressure sensors.
> Additionally to pressure value sensors deliver a temperature value.
> Sensors can be accessed over I2C and SPI, this driver supports
> only I2C access.
> 
> Signed-off-by: Tomislav Denis <tomislav.denis@avl.com>
Ah. Sorry I missed this before, but the -i2c part of the filename is effectively
a wild card. Given we can't know what parts asc will release in the future
that will be incompatible we should avoid generic naming and just pick a
supported part.

Given you are respinning anyway a few things inline I might just have fixed
up whilst applying otherwise.

Thanks,

Jonathan


> ---
>  MAINTAINERS                    |   7 +
>  drivers/iio/pressure/Kconfig   |  12 ++
>  drivers/iio/pressure/Makefile  |   1 +
>  drivers/iio/pressure/dlh-i2c.c | 375 +++++++++++++++++++++++++++++++++++++++++
>  4 files changed, 395 insertions(+)
>  create mode 100644 drivers/iio/pressure/dlh-i2c.c
> 
> diff --git a/MAINTAINERS b/MAINTAINERS
> index d5ea4e4..39d6f0f 100644
> --- a/MAINTAINERS
> +++ b/MAINTAINERS
> @@ -668,6 +668,13 @@ S:	Maintained
>  F:	Documentation/i2c/busses/i2c-ali1563.rst
>  F:	drivers/i2c/busses/i2c-ali1563.c
>  
> +ALL SENSORS DLH SERIES PRESSURE SENSORS DRIVER
> +M:	Tomislav Denis <tomislav.denis@avl.com>
> +W:	http://www.allsensors.com/
> +S:	Maintained
> +L:	linux-iio@vger.kernel.org
> +F:	drivers/iio/pressure/dlh-i2c.c
> +
>  ALLEGRO DVT VIDEO IP CORE DRIVER
>  M:	Michael Tretter <m.tretter@pengutronix.de>
>  R:	Pengutronix Kernel Team <kernel@pengutronix.de>
> diff --git a/drivers/iio/pressure/Kconfig b/drivers/iio/pressure/Kconfig
> index ba420e4..504de3e 100644
> --- a/drivers/iio/pressure/Kconfig
> +++ b/drivers/iio/pressure/Kconfig
> @@ -53,6 +53,18 @@ config IIO_CROS_EC_BARO
>  	  To compile this driver as a module, choose M here: the module
>  	  will be called cros_ec_baro.
>  
> +config DLH_I2C
> +	tristate "All Sensors DLH series low voltage digital pressure sensors"
> +	depends on I2C
> +	select IIO_BUFFER
> +	select IIO_TRIGGERED_BUFFER
> +	help
> +	  Say yes here to build support for the All Sensors DLH series
> +	  pressure sensors driver.
> +
> +	  To compile this driver as a module, choose M here: the module
> +	  will be called dlh-i2c.
> +
>  config DPS310
>  	tristate "Infineon DPS310 pressure and temperature sensor"
>  	depends on I2C
> diff --git a/drivers/iio/pressure/Makefile b/drivers/iio/pressure/Makefile
> index d8f5ace..1851a36 100644
> --- a/drivers/iio/pressure/Makefile
> +++ b/drivers/iio/pressure/Makefile
> @@ -9,6 +9,7 @@ obj-$(CONFIG_BMP280) += bmp280.o
>  bmp280-objs := bmp280-core.o bmp280-regmap.o
>  obj-$(CONFIG_BMP280_I2C) += bmp280-i2c.o
>  obj-$(CONFIG_BMP280_SPI) += bmp280-spi.o
> +obj-$(CONFIG_DLH_I2C) += dlh-i2c.o
>  obj-$(CONFIG_DPS310) += dps310.o
>  obj-$(CONFIG_IIO_CROS_EC_BARO) += cros_ec_baro.o
>  obj-$(CONFIG_HID_SENSOR_PRESS)   += hid-sensor-press.o
> diff --git a/drivers/iio/pressure/dlh-i2c.c b/drivers/iio/pressure/dlh-i2c.c
> new file mode 100644
> index 0000000..b8491a8
> --- /dev/null
> +++ b/drivers/iio/pressure/dlh-i2c.c
> @@ -0,0 +1,375 @@
> +// SPDX-License-Identifier: GPL-2.0
> +/*
> + * All Sensors DLH series low voltage digital pressure sensors
> + *
> + * Copyright (c) 2019 AVL DiTEST GmbH
> + *   Tomislav Denis <tomislav.denis@avl.com>
> + *
> + * Datasheet: http://www.allsensors.com/cad/DS-0355_Rev_B.PDF
> + */
> +
> +#include <linux/module.h>
> +#include <linux/delay.h>
> +#include <linux/i2c.h>
> +#include <linux/iio/iio.h>
> +#include <linux/iio/buffer.h>
> +#include <linux/iio/trigger.h>
This trigger.h header should only need to be included in drivers that create
a trigger, hence shouldn't be included here.

> +#include <linux/iio/trigger_consumer.h>
> +#include <linux/iio/triggered_buffer.h>
> +
> +/* Commands */
> +#define DLH_START_SINGLE    0xAA
> +
> +/* Status bits */
> +#define DLH_STATUS_OK       0x40
> +
> +/* DLH  data format */
> +#define DLH_NUM_READ_BYTES  7
> +#define DLH_NUM_DATA_BYTES  3
> +#define DLH_NUM_PR_BITS     24
> +#define DLH_NUM_TEMP_BITS   24
> +
> +/* DLH  timings */
> +#define DLH_SINGLE_DUT_MS   5
> +
> +enum dhl_ids {
> +	dlhl60d,
> +	dlhl60g,
> +};
> +
> +struct dlh_info {
> +	u8 osdig;           /* digital offset factor */
> +	unsigned int fss;   /* full scale span (inch H2O) */
> +};
> +
> +struct dlh_state {
> +	struct i2c_client *client;
> +	struct dlh_info info;
> +	bool use_interrupt;
> +	struct completion completion;
> +	u8 rx_buf[DLH_NUM_READ_BYTES] ____cacheline_aligned;
> +};
> +
> +static struct dlh_info dlh_info_tbl[] = {
> +	[dlhl60d] = {
> +		.osdig = 2,
> +		.fss = 120,
> +	},
> +	[dlhl60g] = {
> +		.osdig = 10,
> +		.fss = 60,
> +	},
> +};
> +
> +
> +static int dlh_i2c_cmd_start_single(struct dlh_state *st)
> +{
> +	int ret;
> +
> +	ret = i2c_smbus_write_byte(st->client, DLH_START_SINGLE);
> +	if (ret)
> +		dev_err(&st->client->dev,
> +			"%s: I2C write byte failed\n", __func__);
> +
> +	return ret;
> +}
> +
> +static int dlh_i2c_cmd_read_data(struct dlh_state *st)
> +{
> +	int ret;
> +
> +	ret = i2c_master_recv(st->client, st->rx_buf, DLH_NUM_READ_BYTES);
> +	if (ret < 0) {
> +		dev_err(&st->client->dev,
> +			"%s: I2C read block failed\n", __func__);
> +		return ret;
> +	}
> +
> +	if (st->rx_buf[0] != DLH_STATUS_OK) {
> +		dev_err(&st->client->dev,
> +			"%s: invalid status 0x%02x\n", __func__, st->rx_buf[0]);
> +		return -EBUSY;
> +	}
> +
> +	return 0;
> +}
> +
> +static int dlh_i2c_start_capture_and_read(struct dlh_state *st)
> +{
> +	int ret;
> +
> +	if (st->use_interrupt)
> +		reinit_completion(&st->completion);
> +
> +	ret = dlh_i2c_cmd_start_single(st);
> +	if (ret)
> +		return ret;
> +
> +	if (st->use_interrupt) {
> +		ret = wait_for_completion_timeout(&st->completion,
> +			msecs_to_jiffies(DLH_SINGLE_DUT_MS));
> +		if (!ret) {
> +			dev_err(&st->client->dev,
> +				"%s: conversion timed out\n", __func__);
> +			return -ETIMEDOUT;
> +		}
> +	} else {
> +		mdelay(DLH_SINGLE_DUT_MS);
> +	}
> +
> +	return dlh_i2c_cmd_read_data(st);
> +}
> +
> +static int dlh_i2c_read_direct(struct dlh_state *st,
> +	unsigned int *pressure, unsigned int *temperature)
> +{
> +	int ret;
> +
> +	ret = dlh_i2c_start_capture_and_read(st);
> +	if (ret)
> +		return ret;
> +
> +	*pressure = be32_to_cpup((u32 *)&st->rx_buf[1]) >> 8;

Odd casting here.  You are casting to a cpu endian u32 and then
claiming it's big endian.  (__be32 *)



> +	*temperature = be32_to_cpup((u32 *)&st->rx_buf[3]) &
> +		GENMASK(DLH_NUM_TEMP_BITS - 1, 0);
> +
> +	return 0;
> +}
> +
> +static int dlh_i2c_read_raw(struct iio_dev *indio_dev,
> +	struct iio_chan_spec const *channel, int *value,
> +	int *value2, long mask)
> +{
> +	struct dlh_state *st = iio_priv(indio_dev);
> +	unsigned int pressure, temperature;
> +	int ret;
> +	s64 tmp;
> +	s32 rem;
> +
> +	switch (mask) {
> +	case IIO_CHAN_INFO_RAW:
> +		ret = iio_device_claim_direct_mode(indio_dev);
> +		if (ret)
> +			return ret;
> +
> +		ret = dlh_i2c_read_direct(st, &pressure, &temperature);
> +		iio_device_release_direct_mode(indio_dev);
> +		if (ret)
> +			return ret;
> +
> +		switch (channel->type) {
> +		case IIO_PRESSURE:
> +			*value = pressure;
> +			return IIO_VAL_INT;
> +
> +		case IIO_TEMP:
> +			*value = temperature;
> +			return IIO_VAL_INT;
> +
> +		default:
> +			return -EINVAL;
> +		}
> +	case IIO_CHAN_INFO_SCALE:
> +		switch (channel->type) {
> +		case IIO_PRESSURE:
> +			tmp = div_s64(125LL * st->info.fss * 24909 * 100,
> +				1 << DLH_NUM_PR_BITS);
> +			tmp = div_s64_rem(tmp, 1000000000LL, &rem);
> +			*value = tmp;
> +			*value2 = rem;
> +			return IIO_VAL_INT_PLUS_NANO;
> +
> +		case IIO_TEMP:
> +			*value = 125 * 1000;
> +			*value2 = DLH_NUM_TEMP_BITS;
> +			return IIO_VAL_FRACTIONAL_LOG2;
> +
> +		default:
> +			return -EINVAL;
> +		}
> +	case IIO_CHAN_INFO_OFFSET:
> +		switch (channel->type) {
> +		case IIO_PRESSURE:
> +			*value = -125 * st->info.fss * 24909;
> +			*value2 = 100 * st->info.osdig * 100000;
> +			return IIO_VAL_FRACTIONAL;
> +
> +		case IIO_TEMP:
> +			*value = -40 * 1000;
> +			return IIO_VAL_INT;
> +
> +		default:
> +			return -EINVAL;
> +		}
> +	}
> +
> +	return -EINVAL;
> +}
> +
> +static const struct iio_info dlh_i2c_info = {
> +	.read_raw = dlh_i2c_read_raw,
> +};
> +
> +static const struct iio_chan_spec dlh_i2c_channels[] = {
> +	{
> +		.type = IIO_PRESSURE,
> +		.indexed = 1,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.info_mask_shared_by_type =
> +			BIT(IIO_CHAN_INFO_SCALE) |
> +			BIT(IIO_CHAN_INFO_OFFSET),
> +		.scan_index = 0,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = DLH_NUM_PR_BITS,
> +			.storagebits = 32,
> +			.shift = 8,
> +			.endianness = IIO_BE,
> +		},
> +	}, {
> +		.type = IIO_TEMP,
> +		.indexed = 1,
> +		.info_mask_separate = BIT(IIO_CHAN_INFO_RAW),
> +		.info_mask_shared_by_type =
> +			BIT(IIO_CHAN_INFO_SCALE) |
> +			BIT(IIO_CHAN_INFO_OFFSET),
> +		.scan_index = 1,
> +		.scan_type = {
> +			.sign = 'u',
> +			.realbits = DLH_NUM_TEMP_BITS,
> +			.storagebits = 32,
> +			.shift = 8,
> +			.endianness = IIO_BE,
> +		},
> +	}
> +};
> +
> +static irqreturn_t dlh_i2c_trigger_handler(int irq, void *private)
> +{
> +	struct iio_poll_func *pf = private;
> +	struct iio_dev *indio_dev = pf->indio_dev;
> +	struct dlh_state *st = iio_priv(indio_dev);
> +	int ret;
> +	unsigned int chn, i = 0;
> +	__be32 tmp_buf[2];
> +
> +	ret = dlh_i2c_start_capture_and_read(st);
> +	if (ret)
> +		goto out;
> +
> +	for_each_set_bit(chn, indio_dev->active_scan_mask,
> +		indio_dev->masklength) {
> +		memcpy(tmp_buf + i,
> +			&st->rx_buf[1] + chn * DLH_NUM_DATA_BYTES,
> +			DLH_NUM_DATA_BYTES);
> +		i++;
> +	}
> +
> +	iio_push_to_buffers(indio_dev, tmp_buf);
> +
> +out:
> +	iio_trigger_notify_done(indio_dev->trig);
> +
> +	return IRQ_HANDLED;
> +}
> +
> +static irqreturn_t dlh_i2c_interrupt(int irq, void *private)
> +{
> +	struct iio_dev *indio_dev = private;
> +	struct dlh_state *st = iio_priv(indio_dev);
> +
> +	complete(&st->completion);
> +
> +	return IRQ_HANDLED;
> +};
> +
> +static int dlh_i2c_probe(struct i2c_client *client,
> +	const struct i2c_device_id *id)
> +{
> +	struct dlh_state *st;
> +	struct iio_dev *indio_dev;
> +	int ret;
> +
> +	if (!i2c_check_functionality(client->adapter,
> +		I2C_FUNC_I2C | I2C_FUNC_SMBUS_WRITE_BYTE)) {
> +		dev_err(&client->dev,
> +			"adapter doesn't support required i2c functionality\n");
> +		return -EOPNOTSUPP;
> +	}
> +
> +	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*st));
> +	if (!indio_dev) {
> +		dev_err(&client->dev, "failed to allocate iio device\n");
> +		return -ENOMEM;
> +	}
> +
> +	i2c_set_clientdata(client, indio_dev);
> +
> +	st = iio_priv(indio_dev);
> +	st->info = dlh_info_tbl[id->driver_data];
> +	st->client = client;
> +	st->use_interrupt = false;
> +
> +	indio_dev->name = id->name;
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->dev.of_node = client->dev.of_node;
> +	indio_dev->info = &dlh_i2c_info;
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +	indio_dev->channels =  dlh_i2c_channels;
> +	indio_dev->num_channels = ARRAY_SIZE(dlh_i2c_channels);
> +
> +	if (client->irq > 0) {
> +		ret = devm_request_threaded_irq(&client->dev, client->irq,
> +			dlh_i2c_interrupt, NULL,
> +			IRQF_TRIGGER_RISING | IRQF_ONESHOT,
> +			id->name, indio_dev);
> +		if (ret) {
> +			dev_err(&client->dev, "failed to allocate threaded irq");
> +			return ret;
> +		}
> +
> +		st->use_interrupt = true;
> +		init_completion(&st->completion);
> +	}
> +
> +	ret = devm_iio_triggered_buffer_setup(&client->dev, indio_dev,
> +		NULL, &dlh_i2c_trigger_handler, NULL);
> +	if (ret) {
> +		dev_err(&client->dev, "failed to setup iio buffer\n");
> +		return ret;
> +	}
> +
> +	ret = devm_iio_device_register(&client->dev, indio_dev);
> +	if (ret)
> +		dev_err(&client->dev, "failed to register iio device\n");
> +
> +	return ret;
> +}
> +
> +static const struct of_device_id dlh_i2c_of_match[] = {
> +	{ .compatible = "asc,dlhl60d" },
> +	{ .compatible = "asc,dlhl60g" },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(of, dlh_i2c_of_match);
> +
> +static const struct i2c_device_id dlh_i2c_id[] = {
> +	{ "dlhl60d",    dlhl60d },
> +	{ "dlhl60g",    dlhl60g },
> +	{}
> +};
> +MODULE_DEVICE_TABLE(i2c, dlh_i2c_id);
> +
> +static struct i2c_driver dlh_i2c_driver = {
> +	.driver = {
> +		.name = "dlh_i2c",
> +		.of_match_table = dlh_i2c_of_match,
> +	},
> +	.probe = dlh_i2c_probe,
> +	.id_table = dlh_i2c_id,
> +};
> +module_i2c_driver(dlh_i2c_driver);
> +
> +MODULE_AUTHOR("Tomislav Denis <tomislav.denis@avl.com>");
> +MODULE_DESCRIPTION("Driver for All Sensors DLH series pressure sensors");
> +MODULE_LICENSE("GPL v2");

Re: [PATCH v3 3/3] bindings: iio: pressure: Add dlh-i2c documentation

[Rob Herring]

On Sat, Dec 07, 2019 at 11:34:42AM +0000, Jonathan Cameron wrote:
> On Wed, 4 Dec 2019 11:03:54 +0100
> <tomislav.denis@avl.com> wrote:
> 
> > From: Tomislav Denis <tomislav.denis@avl.com>
> > 
> > Add a device tree binding documentation for DLH series pressure
> > sensors.
> > 
> > Signed-off-by: Tomislav Denis <tomislav.denis@avl.com>
> 
> One question for DT maintainers.  
> 
> Should the file be named after a specific part of is a generic
> name for the parts covered acceptable?  I would assume it should
> be a part number, but not sure what precedence there is.

I would use asc,dlhl60.yaml I think. The rule is match the compatible if 
there's only one. Otherwise, no hard rule really. Use the first/oldest 
compatible, do wildcard, or vendor prefix and something else.

> Otherwise looks good to me, but I will let it sit to give time
> for DT review.
> 
> Thanks,
> 
> Jonathan
> 
> > ---
> >  .../bindings/iio/pressure/asc,dlh-i2c.yaml         | 51 ++++++++++++++++++++++
> >  MAINTAINERS                                        |  1 +
> >  2 files changed, 52 insertions(+)
> >  create mode 100644 Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
> > 
> > diff --git a/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml b/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
> > new file mode 100644
> > index 0000000..5de2277
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/iio/pressure/asc,dlh-i2c.yaml
> > @@ -0,0 +1,51 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/iio/pressure/dlh-i2c.yaml#

Note that the filename doesn't match here. Run 'make dt_binding_check'.

> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: All Sensors DLH series low voltage digital pressure sensors
> > +
> > +maintainers:
> > +  - Tomislav Denis <tomislav.denis@avl.com>
> > +
> > +description: |
> > +  Bindings for the All Sensors DLH series pressure sensors.
> > +
> > +  Specifications about the sensors can be found at:
> > +    http://www.allsensors.com/cad/DS-0355_Rev_B.PDF
> > +
> > +properties:
> > +  compatible:
> > +    enum:
> > +      - asc,dlhl60d
> > +      - asc,dlhl60g
> > +
> > +  reg:
> > +    description: I2C device address
> > +    maxItems: 1
> > +
> > +  interrupts:
> > +    description: interrupt mapping for EOC(data ready) pin
> > +    maxItems: 1
> > +
> > +required:
> > +  - compatible
> > +  - reg
> > +
> > +examples:
> > +  - |
> > +    #include <dt-bindings/interrupt-controller/irq.h>
> > +
> > +    i2c0 {
> > +      #address-cells = <1>;
> > +      #size-cells = <0>;
> > +
> > +      pressure@29 {
> > +          compatible = "asc,dlhl60d";
> > +          reg = <0x29>;
> > +          interrupt-parent = <&gpio0>;
> > +          interrupts = <10 IRQ_TYPE_EDGE_RISING>;
> > +      };
> > +    };
> > +...
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index 39d6f0f..8f0eab0 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -674,6 +674,7 @@ W:	http://www.allsensors.com/
> >  S:	Maintained
> >  L:	linux-iio@vger.kernel.org
> >  F:	drivers/iio/pressure/dlh-i2c.c
> > +F:	Documentation/devicetree/bindings/iio/pressure/dlh-i2c.yaml
> >  
> >  ALLEGRO DVT VIDEO IP CORE DRIVER
> >  M:	Michael Tretter <m.tretter@pengutronix.de>
>