A couple of notes inline...
On 10.12.2015 10:10, Matt Ranostay wrote:
Add support for the Atlas Scientific pH-SM chemical sensor that can
detect pH levels of solutions in the range of 0-14.
Signed-off-by: Matt Ranostay <mranostay@xxxxxxxxx>
---
.../bindings/iio/chemical/atlas,ph-sm.txt | 22 ++
drivers/iio/chemical/Kconfig | 13 +
drivers/iio/chemical/Makefile | 1 +
drivers/iio/chemical/atlas-ph-sensor.c | 385
+++++++++++++++++++++
4 files changed, 421 insertions(+)
create mode 100644
Documentation/devicetree/bindings/iio/chemical/atlas,ph-sm.txt
create mode 100644 drivers/iio/chemical/atlas-ph-sensor.c
diff --git
a/Documentation/devicetree/bindings/iio/chemical/atlas,ph-sm.txt
b/Documentation/devicetree/bindings/iio/chemical/atlas,ph-sm.txt
new file mode 100644
index 0000000..a060fd1
--- /dev/null
+++ b/Documentation/devicetree/bindings/iio/chemical/atlas,ph-sm.txt
@@ -0,0 +1,22 @@
+* Atlas Scientific pH-SM OEM sensor
+
+http://www.atlas-scientific.com/_files/_datasheets/_oem/pH_oem_datasheet.pdf
+
+Required properties:
+
+ - compatible: must be "atlas,ph-sm"
+ - reg: the I2C address of the sensor
+ - interrupt-parent: should be the phandle for the interrupt controller
+ - interrupts : the sole interrupt generated by the device
+
+ Refer to interrupt-controller/interrupts.txt for generic interrupt
client
+ node bindings.
+
+Example:
+
+atlas@65 {
+ compatible = "atlas,ph-sm";
+ reg = <0x65>;
+ interrupt-parent = <&gpio1>;
+ interrupts = <16 2>;
+};
diff --git a/drivers/iio/chemical/Kconfig b/drivers/iio/chemical/Kconfig
index 3061b72..753eab6 100644
--- a/drivers/iio/chemical/Kconfig
+++ b/drivers/iio/chemical/Kconfig
@@ -4,6 +4,19 @@
menu "Chemical Sensors"
+config ATLAS_PH_SENSOR
+ tristate "Atlas Scientific OEM pH-SM sensor"
+ depends on I2C
+ select REGMAP_I2C
+ select IIO_BUFFER
+ select IIO_KFIFO_BUF
+ help
+ Say Y here to build I2C interface support for the Atlas
+ Scientific OEM pH-SM sensor.
+
+ To compile this driver as module, choose M here: the
+ module will be called atlas-ph-sensor
+
config VZ89X
tristate "SGX Sensortech MiCS VZ89X VOC sensor"
depends on I2C
diff --git a/drivers/iio/chemical/Makefile b/drivers/iio/chemical/Makefile
index 7292f2d..e9eb852 100644
--- a/drivers/iio/chemical/Makefile
+++ b/drivers/iio/chemical/Makefile
@@ -3,4 +3,5 @@
#
# When adding new entries keep the list in alphabetical order
+obj-$(CONFIG_ATLAS_PH_SENSOR) += atlas-ph-sensor.o
obj-$(CONFIG_VZ89X) += vz89x.o
diff --git a/drivers/iio/chemical/atlas-ph-sensor.c
b/drivers/iio/chemical/atlas-ph-sensor.c
new file mode 100644
index 0000000..6c6f261
--- /dev/null
+++ b/drivers/iio/chemical/atlas-ph-sensor.c
@@ -0,0 +1,385 @@
+/*
+ * atlas-ph-sensor.c - Support for Atlas Scientific OEM pH-SM sensor
+ *
+ * Copyright (C) 2015 Matt Ranostay <mranostay@xxxxxxxxx>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/delay.h>
+#include <linux/mutex.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/regmap.h>
+#include <linux/iio/iio.h>
+#include <linux/iio/buffer.h>
+#include <linux/iio/kfifo_buf.h>
+#include <linux/pm_runtime.h>
+
+#define ATLAS_REGMAP_NAME "atlas_ph_regmap"
+#define ATLAS_DRV_NAME "atlas_ph"
+
+#define ATLAS_REG_DEV_TYPE 0x00
+#define ATLAS_REG_DEV_VERSION 0x01
+
+#define ATLAS_REG_INT_CONTROL 0x04
+#define ATLAS_REG_INT_CONTROL_EN BIT(2)
+
+#define ATLAS_REG_PWR_CONTROL 0x06
+
+#define ATLAS_REG_TEMP_DATA 0x0e
+#define ATLAS_REG_PH_DATA 0x16
+
+#define ATLAS_PH_INT_TIME_IN_US 450000
+
+struct atlas_data {
+ struct i2c_client *client;
+ struct regmap *regmap;
+
+ __be32 buffer[3]; /* 32-bit pH data + 64-bit timestamp */
+};
+
+static bool max30100_is_volatile_reg(struct device *dev, unsigned int
reg)
+{
+ if (reg == ATLAS_REG_INT_CONTROL)
+ return true;
+
+ return false;
+}
+
+static const struct regmap_config atlas_regmap_config = {
+ .name = ATLAS_REGMAP_NAME,
+
+ .reg_bits = 8,
+ .val_bits = 8,
+
+ .volatile_reg = max30100_is_volatile_reg,
+ .max_register = ATLAS_REG_PH_DATA + 4,
+ .cache_type = REGCACHE_FLAT,
+
+};
+
+static const struct iio_chan_spec atlas_channels[] = {
+ {
+ .type = IIO_PH,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+
+ .scan_index = 0,
+ .scan_type = {
+ .sign = 'u',
+ .realbits = 32,
+ .storagebits = 32,
+ .endianness = IIO_BE,
+ },
+ },
+ {
+ .type = IIO_TEMP,
+ .address = ATLAS_REG_TEMP_DATA,
+ .info_mask_separate =
+ BIT(IIO_CHAN_INFO_RAW) | BIT(IIO_CHAN_INFO_SCALE),
+
+ .output = 1,
+ .scan_index = -1
+ },
+};
+
+#ifdef CONFIG_PM
+static int atlas_set_powermode(struct atlas_data *data, int on)
+{
+ return regmap_write(data->regmap, ATLAS_REG_PWR_CONTROL, on);
+}
+#else
+static int atlas_set_powermode(struct atlas_data *data, int on)
+{
+ return 0;
+}
+#endif
^ Why does this need to depend on CONFIG_PM? You may want to use it
if CONFIG_PM is not defined also (See my comment in the remove
funcion).
+
+static int atlas_set_interrupt(struct atlas_data *data, bool state)
+{
+ return regmap_update_bits(data->regmap, ATLAS_REG_INT_CONTROL,
+ ATLAS_REG_INT_CONTROL_EN,
+ state ? ATLAS_REG_INT_CONTROL_EN : 0);
+}
+
+static int atlas_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct atlas_data *data = iio_priv(indio_dev);
+
+ pm_runtime_get_sync(&data->client->dev);
+
+ return atlas_set_interrupt(data, true);
+}
+
+static int atlas_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct atlas_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = atlas_set_interrupt(data, false);
+ if (ret)
+ return ret;
+
+ pm_runtime_mark_last_busy(&data->client->dev);
+ return pm_runtime_put_autosuspend(&data->client->dev);
+}
+
+static const struct iio_buffer_setup_ops atlas_buffer_setup_ops = {
+ .postenable = atlas_buffer_postenable,
+ .predisable = atlas_buffer_predisable,
+};
+
+static irqreturn_t atlas_interrupt_handler(int irq, void *private)
+{
+ struct iio_dev *indio_dev = private;
+ struct atlas_data *data = iio_priv(indio_dev);
+ int ret;
+
+ ret = i2c_smbus_read_i2c_block_data(data->client,
ATLAS_REG_PH_DATA,
+ sizeof(data->buffer[0]), (u8 *)
&data->buffer);
+ if (!ret)
+ iio_push_to_buffers_with_timestamp(indio_dev,
data->buffer,
+ iio_get_time_ns());
+
+ /* re-enable interrupt */
+ atlas_set_interrupt(data, true);
+
+ return IRQ_HANDLED;
+}
+
+static int atlas_read_ph_measurement(struct atlas_data *data, __be32
*val)
+{
+ struct device *dev = &data->client->dev;
+ int suspended = pm_runtime_suspended(dev);
+ int ret;
+
+ ret = pm_runtime_get_sync(dev);
+ if (ret)
+ return ret;
+
+ if (suspended)
+ usleep_range(ATLAS_PH_INT_TIME_IN_US,
+ ATLAS_PH_INT_TIME_IN_US + 100000);
+
+ ret = i2c_smbus_read_i2c_block_data(data->client,
ATLAS_REG_PH_DATA,
+ sizeof(*val), (u8 *) val);
+
+ pm_runtime_mark_last_busy(dev);
+ pm_runtime_put_autosuspend(dev);
+
+ return ret;
+}
+
+static int atlas_read_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int *val, int *val2, long mask)
+{
+ struct atlas_data *data = iio_priv(indio_dev);
+
+ switch (mask) {
+ case IIO_CHAN_INFO_RAW: {
+ int ret;
+ __be32 reg;
+
+ mutex_lock(&indio_dev->mlock);
+
+ if (iio_buffer_enabled(indio_dev)) {
+ ret = -EINVAL;
+ goto error_busy;
+ }
+
+ switch (chan->type) {
+ case IIO_TEMP:
+ ret = regmap_bulk_read(data->regmap,
chan->address,
+ (u8 *) ®, sizeof(reg));
+ break;
+ case IIO_PH:
+ ret = atlas_read_ph_measurement(data, ®);
+ break;
+ default:
+ ret = -EINVAL;
+ }
+
+ if (!ret) {
+ *val = be32_to_cpu(reg);
+ ret = IIO_VAL_INT;
+ }
+
+error_busy:
+ mutex_unlock(&indio_dev->mlock);
+ return ret;
+ }
+ case IIO_CHAN_INFO_SCALE:
+ *val = 0; /* 0.001 */
+ *val2 = 1000;
+ return IIO_VAL_INT_PLUS_MICRO;
+ }
+
+ return -EINVAL;
+}
+
+static int atlas_write_raw(struct iio_dev *indio_dev,
+ struct iio_chan_spec const *chan,
+ int val, int val2, long mask)
+{
+ struct atlas_data *data = iio_priv(indio_dev);
+ __be32 reg = cpu_to_be32(val);
+
+ if (val2 != 0)
+ return -EINVAL;
+
+ if (mask != IIO_CHAN_INFO_RAW || chan->type != IIO_TEMP)
+ return -EINVAL;
+
+ return regmap_bulk_write(data->regmap, chan->address, ®, 4);
+}
+
+static const struct iio_info atlas_info = {
+ .driver_module = THIS_MODULE,
+ .read_raw = atlas_read_raw,
+ .write_raw = atlas_write_raw,
+};
+
+static int atlas_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct atlas_data *data;
+ struct iio_buffer *buffer;
+ struct iio_dev *indio_dev;
+ int ret;
+
+ indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data));
+ if (!indio_dev)
+ return -ENOMEM;
+
+ buffer = devm_iio_kfifo_allocate(&client->dev);
+ if (!buffer)
+ return -ENOMEM;
+
+ iio_device_attach_buffer(indio_dev, buffer);
+
+ indio_dev->info = &atlas_info;
+ indio_dev->name = ATLAS_DRV_NAME;
+ indio_dev->channels = atlas_channels;
+ indio_dev->modes = (INDIO_BUFFER_SOFTWARE | INDIO_DIRECT_MODE);
+ indio_dev->setup_ops = &atlas_buffer_setup_ops;
+
+ data = iio_priv(indio_dev);
+ data->client = client;
+
+ i2c_set_clientdata(client, indio_dev);
+
+ data->regmap = devm_regmap_init_i2c(client, &atlas_regmap_config);
+ if (IS_ERR(data->regmap)) {
+ dev_err(&client->dev, "regmap initialization failed\n");
+ return PTR_ERR(data->regmap);
+ }
+
+ ret = pm_runtime_set_active(&client->dev);
+ if (ret)
+ return ret;
+
+ if (client->irq <= 0) {
+ dev_err(&client->dev, "no valid irq defined\n");
+ return -EINVAL;
+ }
+
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ NULL, atlas_interrupt_handler,
+ IRQF_TRIGGER_FALLING |
IRQF_ONESHOT,
+ "atlas_event",
+ indio_dev);
+ if (ret) {
+ dev_err(&client->dev, "request irq (%d) failed\n",
client->irq);
+ return ret;
+ }
+
+ pm_runtime_enable(&client->dev);
+ pm_runtime_set_autosuspend_delay(&client->dev, 2500);
+ pm_runtime_use_autosuspend(&client->dev);
+
+ ret = atlas_set_powermode(data, 0);
+ if (ret)
+ return ret;
Unless I am missing something I don't think you need to explicitly
set power off here ^. Runtime pm will call your suspend callback in
some seconds anyway, so it seems redundant.
