From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mga04.intel.com ([192.55.52.120]:47124 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754500AbbLPJ0E (ORCPT ); Wed, 16 Dec 2015 04:26:04 -0500 Subject: Re: [RFC v2 3/3] iio: chemical: add Atlas pH-SM sensor support To: Matt Ranostay References: <1450171574-3283-1-git-send-email-mranostay@gmail.com> <1450171574-3283-4-git-send-email-mranostay@gmail.com> <566FF36E.4090501@intel.com> Cc: "linux-iio@vger.kernel.org" , Jonathan Cameron From: Adriana Reus Message-ID: <56712E06.6080605@intel.com> Date: Wed, 16 Dec 2015 11:25:26 +0200 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Sender: linux-iio-owner@vger.kernel.org List-Id: linux-iio@vger.kernel.org On 15.12.2015 17:19, Matt Ranostay wrote: > On Tue, Dec 15, 2015 at 3:03 AM, Adriana Reus wrote: >> >> >> On 15.12.2015 11:26, 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 >>> --- >>> .../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 | 431 >>> +++++++++++++++++++++ >>> 4 files changed, 467 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..cffa190 >>> --- /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..a358e4b 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_TRIGGERED_BUFFER >>> + 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..63da26b >>> --- /dev/null >>> +++ b/drivers/iio/chemical/atlas-ph-sensor.c >>> @@ -0,0 +1,431 @@ >>> +/* >>> + * atlas-ph-sensor.c - Support for Atlas Scientific OEM pH-SM sensor >>> + * >>> + * Copyright (C) 2015 Matt Ranostay >>> + * >>> + * 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 >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> +#include >>> + >>> +#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 iio_trigger *trig; >>> + struct regmap *regmap; >>> + >>> + __be32 buffer[4]; /* 32-bit pH data + 32-bit pad + 64-bit >>> timestamp */ >>> +}; >>> + >>> +static bool atlas_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 = atlas_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 >>> + }, >>> +}; >>> + >>> +static int atlas_set_powermode(struct atlas_data *data, int on) >>> +{ >>> + return regmap_write(data->regmap, ATLAS_REG_PWR_CONTROL, on); >>> +} >>> + >>> +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); >> >> ^ pm_runtime_get_sync may return errors >> >>> + >>> + 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_trigger_ops atlas_interrupt_trigger_ops = { >>> + .owner = THIS_MODULE, >>> +}; >>> + >>> +static const struct iio_buffer_setup_ops atlas_buffer_setup_ops = { >>> + .postenable = atlas_buffer_postenable, >>> + .predisable = atlas_buffer_predisable, >>> +}; >>> + >>> +static irqreturn_t atlas_trigger_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 > 0) >>> + iio_push_to_buffers_with_timestamp(indio_dev, >>> data->buffer, >>> + iio_get_time_ns()); >>> + >>> + iio_trigger_notify_done(indio_dev->trig); >>> + >>> + return IRQ_HANDLED; >>> +} >>> + >>> +static irqreturn_t atlas_interrupt_handler(int irq, void *private) >>> +{ >>> + struct iio_dev *indio_dev = private; >>> + struct atlas_data *data = iio_priv(indio_dev); >>> + >>> + /* 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; >> >> ^ pm_runtime_get_sync can also return 1 (if the device is already >> active).. in which case you definitely don't want to return here. >> Also if this does return an error you may want to call put_noidle >> because get_sync increments the device usage_count before it tries to >> resume and you can end up with an unbalanced count there. >>> >>> + >>> + 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); >> >> ^ also may return err code > > What would be proper handling of it here though? *_put_noidle ? No need for *_put_noidle AFAICT in this case, so just returning the error code should be ok. > > >> >>> + >>> + return ret == sizeof(*val) ? 0 : -EINVAL; >>> +} >>> + >>> +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 = -EBUSY; >>> + goto error_busy; >>> + } >>> + >>> + switch (chan->type) { >>> + case IIO_TEMP: >>> + ret = regmap_bulk_read(data->regmap, >>> chan->address, >>> + (u8 *) ®, sizeof(reg)); >> >> ^ what would happen if temp is read while the chip is suspended >> runtime-pm wise? Unless I am missing something the chip may be powered >> off at this point. >> >>> + 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_trigger *trig; >>> + struct iio_dev *indio_dev; >>> + int ret; >>> + >>> + indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*data)); >>> + if (!indio_dev) >>> + return -ENOMEM; >>> + >>> + 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; >>> + indio_dev->dev.parent = &client->dev; >>> + >>> + trig = devm_iio_trigger_alloc(&client->dev, "%s-dev%d", >>> + indio_dev->name, indio_dev->id); >>> + >>> + if (!trig) >>> + return -ENOMEM; >>> + >>> + data = iio_priv(indio_dev); >>> + data->client = client; >>> + data->trig = trig; >>> + trig->dev.parent = indio_dev->dev.parent; >>> + trig->ops = &atlas_interrupt_trigger_ops; >>> + iio_trigger_set_drvdata(trig, indio_dev); >>> + >>> + 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 = iio_trigger_register(trig); >>> + if (ret) { >>> + dev_err(&client->dev, "failed to register trigger\n"); >>> + return ret; >>> + } >>> + >>> + ret = iio_triggered_buffer_setup(indio_dev, NULL, >>> + &atlas_trigger_handler, NULL); >>> + >>> + if (ret) { >>> + dev_err(&client->dev, "cannot setup iio trigger\n"); >>> + goto unregister_trigger; >>> + } >>> + >>> + ret = devm_request_threaded_irq(&client->dev, client->irq, >>> + NULL, atlas_interrupt_handler, >>> + IRQF_TRIGGER_FALLING | >>> IRQF_ONESHOT, >>> + "atlas_irq", >>> + indio_dev); >>> + if (ret) { >>> + dev_err(&client->dev, "request irq (%d) failed\n", >>> client->irq); >>> + goto unregister_buffer; >>> + } >>> + >>> + ret = atlas_set_powermode(data, 1); >>> + if (ret) { >>> + dev_err(&client->dev, "cannot power device on"); >>> + goto unregister_buffer; >>> + } >>> + >>> + pm_runtime_enable(&client->dev); >>> + pm_runtime_set_autosuspend_delay(&client->dev, 2500); >>> + pm_runtime_use_autosuspend(&client->dev); >>> + >>> + ret = iio_device_register(indio_dev); >>> + if (ret) { >>> + dev_err(&client->dev, "unable to register device\n"); >>> + goto unregister_buffer; >>> + } >>> + >>> + return 0; >>> + >>> +unregister_buffer: >>> + iio_triggered_buffer_cleanup(indio_dev); >>> + >>> +unregister_trigger: >>> + iio_trigger_unregister(data->trig); >>> + >>> + return ret; >>> +} >>> + >>> +static int atlas_remove(struct i2c_client *client) >>> +{ >>> + struct iio_dev *indio_dev = i2c_get_clientdata(client); >>> + struct atlas_data *data = iio_priv(indio_dev); >>> + >>> + iio_device_unregister(indio_dev); >>> + iio_triggered_buffer_cleanup(indio_dev); >>> + iio_trigger_unregister(data->trig); >>> + >>> + pm_runtime_disable(&client->dev); >>> + pm_runtime_set_suspended(&client->dev); >>> + pm_runtime_put_noidle(&client->dev); >>> + >>> + return atlas_set_powermode(data, 0); >>> +} >>> + >>> +#ifdef CONFIG_PM >>> +static int atlas_runtime_suspend(struct device *dev) >>> +{ >>> + struct atlas_data *data = >>> + iio_priv(i2c_get_clientdata(to_i2c_client(dev))); >>> + >>> + return atlas_set_powermode(data, 0); >>> +} >>> + >>> +static int atlas_runtime_resume(struct device *dev) >>> +{ >>> + struct atlas_data *data = >>> + iio_priv(i2c_get_clientdata(to_i2c_client(dev))); >>> + >>> + return atlas_set_powermode(data, 1); >>> +} >>> +#endif >>> + >>> +static const struct dev_pm_ops atlas_pm_ops = { >>> + SET_RUNTIME_PM_OPS(atlas_runtime_suspend, >>> + atlas_runtime_resume, NULL) >>> +}; >>> + >>> +static const struct i2c_device_id atlas_id[] = { >>> + { "atlas-ph-sm", 0 }, >>> + {} >>> +}; >>> +MODULE_DEVICE_TABLE(i2c, atlas_id); >>> + >>> +static const struct of_device_id atlas_dt_ids[] = { >>> + { .compatible = "atlas,ph-sm" }, >>> + { } >>> +}; >>> +MODULE_DEVICE_TABLE(of, atlas_dt_ids); >>> + >>> +static struct i2c_driver atlas_driver = { >>> + .driver = { >>> + .name = ATLAS_DRV_NAME, >>> + .of_match_table = of_match_ptr(atlas_dt_ids), >>> + .pm = &atlas_pm_ops, >>> + }, >>> + .probe = atlas_probe, >>> + .remove = atlas_remove, >>> + .id_table = atlas_id, >>> +}; >>> +module_i2c_driver(atlas_driver); >>> + >>> +MODULE_AUTHOR("Matt Ranostay "); >>> +MODULE_DESCRIPTION("Atlas Scientific pH-SM sensor"); >>> +MODULE_LICENSE("GPL"); >>> >>