Re: [PATCH v9 8/8] drivers:input:tsc2007: add iio interface to read external ADC input and temperature

H. Nikolaus Schaller
2017-02-18T11:35:51Z

> Am 17.02.2017 um 22:27 schrieb Dmitry Torokhov <dmitry.torokhov-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>:
>
> On Fri, Dec 30, 2016 at 08:36:30PM +0000, Jonathan Cameron wrote:
>> On 28/12/16 14:53, H. Nikolaus Schaller wrote:
>>> The tsc2007 chip not only has a resistive touch screen controller but
>>> also an external AUX adc imput which can be used for an ambient
>>> light sensor, battery voltage monitoring or any general purpose.
>>>
>>> Additionally it can measure the chip temperature.
>>>
>>> This extension provides an iio interface for these adc channels.
>>>
>>> Since it is not wasting much resources and is very straightforward,
>>> we simply provide all other adc channels as optional iio interfaces
>>> as weel. This can be used for debugging or special applications.
>>>
>>> This patch also splits the tsc2007 driver in several source files:
>>> tsc2007.h -- constants, structs and stubs
>>> tsc2007_core.c -- functional parts of the original driver
>>> tsc2007_iio.c -- the optional iio stuff
>>>
>>> Makefile magic allows to conditionally link the iio stuff
>>> if CONFIG_IIO=y or =m in a way that it works with
>>> CONFIG_TOUCHSCREEN_TSC2007=m.
>>>
>>> Signed-off-by: H. Nikolaus Schaller <hns-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
>>> Reviewed-by: Jonathan Cameron <jic23-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
>> Just for the record, I'm happy with the few changes from earlier versions.
>
> I untangled this from the rest of the patches (as it turned out to be
> the least controversial ;) ) and applied with some minor changes (see
> below). Please take a look at my tsc2007 branch on kernel.org to see if
> I missed anything.

Looks good!

BR and thanks,
Nikolaus

>
> Thanks.
>
>>
>> Jonathan
>>> ---
>>> drivers/input/touchscreen/Kconfig | 10 ++
>>> drivers/input/touchscreen/Makefile | 2 +
>>> drivers/input/touchscreen/tsc2007.h | 116 ++++++++++++++++
>>> .../touchscreen/{tsc2007.c => tsc2007_core.c} | 95 +++----------
>>> drivers/input/touchscreen/tsc2007_iio.c | 150 +++++++++++++++++++++
>>> 5 files changed, 299 insertions(+), 74 deletions(-)
>>> create mode 100644 drivers/input/touchscreen/tsc2007.h
>>> rename drivers/input/touchscreen/{tsc2007.c => tsc2007_core.c} (86%)
>>> create mode 100644 drivers/input/touchscreen/tsc2007_iio.c
>>>
>>> diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
>>> index efca013..1616a8d 100644
>>> --- a/drivers/input/touchscreen/Kconfig
>>> +++ b/drivers/input/touchscreen/Kconfig
>>> @@ -1035,6 +1035,16 @@ config TOUCHSCREEN_TSC2007
>>> To compile this driver as a module, choose M here: the
>>> module will be called tsc2007.
>>>
>>> +config TOUCHSCREEN_TSC2007_IIO
>>> + bool "IIO interface for external ADC input and temperature"
>>> + depends on TOUCHSCREEN_TSC2007
>>> + depends on IIO=y || IIO=TOUCHSCREEN_TSC2007
>>> + help
>>> + Saying Y here adds an iio interface to the tsc2007 which
>>> + provides values for the AUX input (used for e.g. battery
>>> + or ambient light monitoring), temperature and raw input
>>> + values.
>>> +
>>> config TOUCHSCREEN_W90X900
>>> tristate "W90P910 touchscreen driver"
>>> depends on ARCH_W90X900
>>> diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
>>> index 81b8645..05d1cc8 100644
>>> --- a/drivers/input/touchscreen/Makefile
>>> +++ b/drivers/input/touchscreen/Makefile
>>> @@ -80,6 +80,8 @@ obj-$(CONFIG_TOUCHSCREEN_TSC_SERIO) += tsc40.o
>>> obj-$(CONFIG_TOUCHSCREEN_TSC200X_CORE) += tsc200x-core.o
>>> obj-$(CONFIG_TOUCHSCREEN_TSC2004) += tsc2004.o
>>> obj-$(CONFIG_TOUCHSCREEN_TSC2005) += tsc2005.o
>>> +tsc2007-y := tsc2007_core.o
>>> +tsc2007-$(CONFIG_TOUCHSCREEN_TSC2007_IIO) += tsc2007_iio.o
>>> obj-$(CONFIG_TOUCHSCREEN_TSC2007) += tsc2007.o
>>> obj-$(CONFIG_TOUCHSCREEN_UCB1400) += ucb1400_ts.o
>>> obj-$(CONFIG_TOUCHSCREEN_WACOM_W8001) += wacom_w8001.o
>>> diff --git a/drivers/input/touchscreen/tsc2007.h b/drivers/input/touchscreen/tsc2007.h
>>> new file mode 100644
>>> index 0000000..16efb60
>>> --- /dev/null
>>> +++ b/drivers/input/touchscreen/tsc2007.h
>>> @@ -0,0 +1,116 @@
>>> +/*
>>> + * Copyright (c) 2008 MtekVision Co., Ltd.
>>> + * Kwangwoo Lee <kwlee-ec7hoAtq5SbSUeElwK9/Pw@public.gmane.org>
>>> + *
>>> + * Using code from:
>>> + * - ads7846.c
>>> + * Copyright (c) 2005 David Brownell
>>> + * Copyright (c) 2006 Nokia Corporation
>>> + * - corgi_ts.c
>>> + * Copyright (C) 2004-2005 Richard Purdie
>>> + * - omap_ts.[hc], ads7846.h, ts_osk.c
>>> + * Copyright (C) 2002 MontaVista Software
>>> + * Copyright (C) 2004 Texas Instruments
>>> + * Copyright (C) 2005 Dirk Behme
>>> + *
>>> + * This program is free software; you can redistribute it and/or modify
>>> + * it under the terms of the GNU General Public License version 2 as
>>> + * published by the Free Software Foundation.
>>> + */
>>> +
>>> +#include <linux/input/touchscreen.h>
>>> +
>>> +#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
>>> +#define TSC2007_MEASURE_AUX (0x2 << 4)
>>> +#define TSC2007_MEASURE_TEMP1 (0x4 << 4)
>>> +#define TSC2007_ACTIVATE_XN (0x8 << 4)
>>> +#define TSC2007_ACTIVATE_YN (0x9 << 4)
>>> +#define TSC2007_ACTIVATE_YP_XN (0xa << 4)
>>> +#define TSC2007_SETUP (0xb << 4)
>>> +#define TSC2007_MEASURE_X (0xc << 4)
>>> +#define TSC2007_MEASURE_Y (0xd << 4)
>>> +#define TSC2007_MEASURE_Z1 (0xe << 4)
>>> +#define TSC2007_MEASURE_Z2 (0xf << 4)
>>> +
>>> +#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2)
>>> +#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2)
>>> +#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2)
>>> +#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2)
>>> +
>>> +#define TSC2007_12BIT (0x0 << 1)
>>> +#define TSC2007_8BIT (0x1 << 1)
>>> +
>>> +#define MAX_12BIT ((1 << 12) - 1)
>>> +
>>> +#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)
>>> +
>>> +#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y)
>>> +#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1)
>>> +#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2)
>>> +#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X)
>>> +#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)
>>> +
>>> +struct ts_event {
>>> + u16 x;
>>> + u16 y;
>>> + u16 z1, z2;
>>> +};
>>> +
>>> +struct tsc2007 {
>>> + struct input_dev *input;
>>> + char phys[32];
>>> +
>>> + struct i2c_client *client;
>>> +
>>> + u16 model;
>>> + u16 x_plate_ohms;
>>> +
>>> + struct touchscreen_properties prop;
>>> +
>>> + bool report_resistance;
>>> + u16 min_x;
>>> + u16 min_y;
>>> + u16 max_x;
>>> + u16 max_y;
>>> + u16 max_rt;
>>> + unsigned long poll_period; /* in jiffies */
>>> + int fuzzx;
>>> + int fuzzy;
>>> + int fuzzz;
>>> +
>>> + unsigned int gpio;
>>> + int irq;
>>> +
>>> + wait_queue_head_t wait;
>>> + bool stopped;
>>> + bool pendown;
>>> +
>>> + int (*get_pendown_state)(struct device *);
>>> + void (*clear_penirq)(void);
>>> +
>>> + struct mutex mlock;
>>> + struct iio_dev *iio_dev; /* optional */
>>> +};
>>> +
>>> +int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd);
>>> +u32 tsc2007_calculate_resistance(struct tsc2007 *tsc,
>>> + struct ts_event *tc);
>>> +bool tsc2007_is_pen_down(struct tsc2007 *ts);
>>> +
>>> +#if IS_ENABLED(CONFIG_TOUCHSCREEN_TSC2007_IIO)
>>> +
>>> +/* defined in tsc2007_iio.c */
>>> +int tsc2007_iio_configure(struct tsc2007 *ts);
>>> +void tsc2007_iio_unconfigure(struct tsc2007 *ts);
>>> +
>>> +#else /* CONFIG_TOUCHSCREEN_TSC2007_IIO */
>>> +
>>> +static inline int tsc2007_iio_configure(struct tsc2007 *ts)
>>> +{
>>> + return 0;
>>> +}
>>> +static inline void tsc2007_iio_unconfigure(struct tsc2007 *ts)
>>> +{
>>> +}
>>> +
>>> +#endif /* CONFIG_TOUCHSCREEN_TSC2007_IIO */
>>> diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007_core.c
>>> similarity index 86%
>>> rename from drivers/input/touchscreen/tsc2007.c
>>> rename to drivers/input/touchscreen/tsc2007_core.c
>>> index 76b462b..812ded8 100644
>>> --- a/drivers/input/touchscreen/tsc2007.c
>>> +++ b/drivers/input/touchscreen/tsc2007_core.c
>>> @@ -27,79 +27,11 @@
>>> #include <linux/i2c.h>
>>> #include <linux/i2c/tsc2007.h>
>>> #include <linux/of_device.h>
>>> -#include <linux/of.h>
>>> #include <linux/of_gpio.h>
>>> -#include <linux/input/touchscreen.h>
>>> -
>>> -#define TSC2007_MEASURE_TEMP0 (0x0 << 4)
>>> -#define TSC2007_MEASURE_AUX (0x2 << 4)
>>> -#define TSC2007_MEASURE_TEMP1 (0x4 << 4)
>>> -#define TSC2007_ACTIVATE_XN (0x8 << 4)
>>> -#define TSC2007_ACTIVATE_YN (0x9 << 4)
>>> -#define TSC2007_ACTIVATE_YP_XN (0xa << 4)
>>> -#define TSC2007_SETUP (0xb << 4)
>>> -#define TSC2007_MEASURE_X (0xc << 4)
>>> -#define TSC2007_MEASURE_Y (0xd << 4)
>>> -#define TSC2007_MEASURE_Z1 (0xe << 4)
>>> -#define TSC2007_MEASURE_Z2 (0xf << 4)
>>> -
>>> -#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2)
>>> -#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2)
>>> -#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2)
>>> -#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2)
>>> -
>>> -#define TSC2007_12BIT (0x0 << 1)
>>> -#define TSC2007_8BIT (0x1 << 1)
>>> -
>>> -#define MAX_12BIT ((1 << 12) - 1)
>>> -
>>> -#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0)
>>> -
>>> -#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y)
>>> -#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1)
>>> -#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2)
>>> -#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X)
>>> -#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN)
>>> -
>>> -struct ts_event {
>>> - u16 x;
>>> - u16 y;
>>> - u16 z1, z2;
>>> -};
>>> -
>>> -struct tsc2007 {
>>> - struct input_dev *input;
>>> - char phys[32];
>>> -
>>> - struct i2c_client *client;
>>> -
>>> - u16 model;
>>> - u16 x_plate_ohms;
>>> -
>>> - struct touchscreen_properties prop;
>>> -
>>> - bool report_resistance;
>>> - u16 min_x;
>>> - u16 min_y;
>>> - u16 max_x;
>>> - u16 max_y;
>>> - u16 max_rt;
>>> - unsigned long poll_period; /* in jiffies */
>>> - int fuzzx;
>>> - int fuzzy;
>>> - int fuzzz;
>>> -
>>> - unsigned gpio;
>>> - int irq;
>>> -
>>> - wait_queue_head_t wait;
>>> - bool stopped;
>>> +#include "tsc2007.h"
>>>
>>> - int (*get_pendown_state)(struct device *);
>>> - void (*clear_penirq)(void);
>>> -};
>>>
>>> -static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
>>> +int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd)
>>> {
>>> s32 data;
>>> u16 val;
>>> @@ -137,7 +69,7 @@ static void tsc2007_read_values(struct tsc2007 *tsc, struct ts_event *tc)
>>> tsc2007_xfer(tsc, PWRDOWN);
>>> }
>>>
>>> -static u32 tsc2007_calculate_resistance(struct tsc2007 *tsc,
>
> Kept as tsc2007_calculate_resistance for now.
>
>>> +u32 tsc2007_calculate_resistance(struct tsc2007 *tsc,
>>> struct ts_event *tc)
>>> {
>>> u32 rt = 0;
>>> @@ -158,7 +90,7 @@ static u32 tsc2007_calculate_resistance(struct tsc2007 *tsc,
>>> return rt;
>>> }
>>>
>>> -static bool tsc2007_is_pen_down(struct tsc2007 *ts)
>>> +bool tsc2007_is_pen_down(struct tsc2007 *ts)
>>> {
>>> /*
>>> * NOTE: We can't rely on the pressure to determine the pen down
>>> @@ -191,7 +123,10 @@ static irqreturn_t tsc2007_soft_irq(int irq, void *handle)
>>> while (!ts->stopped && tsc2007_is_pen_down(ts)) {
>>>
>>> /* pen is down, continue with the measurement */
>>> +
>>> + mutex_lock(&ts->mlock);
>>> tsc2007_read_values(ts, &tc);
>>> + mutex_unlock(&ts->mlock);
>>>
>>> rt = tsc2007_calculate_resistance(ts, &tc);
>>>
>>> @@ -441,7 +376,8 @@ static void tsc2007_call_exit_platform_hw(void *data)
>>> static int tsc2007_probe(struct i2c_client *client,
>>> const struct i2c_device_id *id)
>>> {
>>> - const struct tsc2007_platform_data *pdata = dev_get_platdata(&client->dev);
>>> + const struct tsc2007_platform_data *pdata =
>>> + dev_get_platdata(&client->dev);
>>> struct tsc2007 *ts;
>>> struct input_dev *input_dev;
>>> int err;
>>> @@ -463,7 +399,9 @@ static int tsc2007_probe(struct i2c_client *client,
>>> ts->client = client;
>>> ts->irq = client->irq;
>>> ts->input = input_dev;
>>> +
>>> init_waitqueue_head(&ts->wait);
>>> + mutex_init(&ts->mlock);
>>>
>>> snprintf(ts->phys, sizeof(ts->phys),
>>> "%s/input0", dev_name(&client->dev));
>>> @@ -534,7 +472,7 @@ static int tsc2007_probe(struct i2c_client *client,
>>> if (err < 0) {
>>> dev_err(&client->dev,
>>> "Failed to setup chip: %d\n", err);
>>> - return err; /* usually, chip does not respond */
>>> + return err; /* chip does not respond */
>>> }
>>>
>>> err = input_register_device(input_dev);
>>> @@ -544,6 +482,14 @@ static int tsc2007_probe(struct i2c_client *client,
>>> return err;
>>> }
>>>
>>> + return tsc2007_iio_configure(ts);
>>> +}
>>> +
>>> +static int tsc2007_remove(struct i2c_client *client)
>>> +{
>>> + struct tsc2007 *ts = i2c_get_clientdata(client);
>>> +
>>> + tsc2007_iio_unconfigure(ts);
>>> return 0;
>>> }
>>>
>>> @@ -569,6 +515,7 @@ static struct i2c_driver tsc2007_driver = {
>>> },
>>> .id_table = tsc2007_idtable,
>>> .probe = tsc2007_probe,
>>> + .remove = tsc2007_remove,
>>> };
>>>
>>> module_i2c_driver(tsc2007_driver);
>>> diff --git a/drivers/input/touchscreen/tsc2007_iio.c b/drivers/input/touchscreen/tsc2007_iio.c
>>> new file mode 100644
>>> index 0000000..ed79944
>>> --- /dev/null
>>> +++ b/drivers/input/touchscreen/tsc2007_iio.c
>>> @@ -0,0 +1,150 @@
>>> +/*
>>> + * Copyright (c) 2016 Golden Delicious Comp. GmbH&Co. KG
>>> + * Nikolaus Schaller <hns-xXXSsgcRVICgSpxsJD1C4w@public.gmane.org>
>>> + *
>>> + * This program is free software; you can redistribute it and/or modify
>>> + * it under the terms of the GNU General Public License version 2 as
>>> + * published by the Free Software Foundation.
>>> + */
>>> +
>>> +#include <linux/i2c.h>
>>> +#include <linux/iio/iio.h>
>>> +#include "tsc2007.h"
>>> +
>>> +struct tsc2007_iio {
>>> + struct tsc2007 *ts;
>>> +};
>>> +
>>> +#define TSC2007_CHAN_IIO(_chan, _name, _type, _chan_info) \
>>> +{ \
>>> + .datasheet_name = _name, \
>>> + .type = _type, \
>>> + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
>>> + BIT(_chan_info), \
>>> + .indexed = 1, \
>>> + .channel = _chan, \
>>> +}
>>> +
>>> +static const struct iio_chan_spec tsc2007_iio_channel[] = {
>>> + TSC2007_CHAN_IIO(0, "x", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(1, "y", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(2, "z1", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(3, "z2", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(4, "adc", IIO_VOLTAGE, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(5, "rt", IIO_VOLTAGE, IIO_CHAN_INFO_RAW), /* Ohms? */
>>> + TSC2007_CHAN_IIO(6, "pen", IIO_PRESSURE, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(7, "temp0", IIO_TEMP, IIO_CHAN_INFO_RAW),
>>> + TSC2007_CHAN_IIO(8, "temp1", IIO_TEMP, IIO_CHAN_INFO_RAW),
>>> +};
>>> +
>>> +static int tsc2007_read_raw(struct iio_dev *indio_dev,
>>> + struct iio_chan_spec const *chan, int *val, int *val2, long mask)
>>> +{
>>> + struct tsc2007_iio *iio = iio_priv(indio_dev);
>>> + struct tsc2007 *tsc = iio->ts;
>>> + int adc_chan = chan->channel;
>>> + int ret = 0;
>>> +
>>> + if (adc_chan >= ARRAY_SIZE(tsc2007_iio_channel))
>>> + return -EINVAL;
>>> +
>>> + if (mask != IIO_CHAN_INFO_RAW)
>>> + return -EINVAL;
>>> +
>>> + mutex_lock(&tsc->mlock);
>>> +
>>> + switch (chan->channel) {
>>> + case 0:
>>> + *val = tsc2007_xfer(tsc, READ_X);
>>> + break;
>>> + case 1:
>>> + *val = tsc2007_xfer(tsc, READ_Y);
>>> + break;
>>> + case 2:
>>> + *val = tsc2007_xfer(tsc, READ_Z1);
>>> + break;
>>> + case 3:
>>> + *val = tsc2007_xfer(tsc, READ_Z2);
>>> + break;
>>> + case 4:
>>> + *val = tsc2007_xfer(tsc, (ADC_ON_12BIT | TSC2007_MEASURE_AUX));
>>> + break;
>>> + case 5: {
>>> + struct ts_event tc;
>>> +
>>> + tc.x = tsc2007_xfer(tsc, READ_X);
>>> + tc.z1 = tsc2007_xfer(tsc, READ_Z1);
>>> + tc.z2 = tsc2007_xfer(tsc, READ_Z2);
>>> + *val = tsc2007_calculate_resistance(tsc, &tc);
>>> + break;
>>> + }
>>> + case 6:
>>> + *val = tsc2007_is_pen_down(tsc);
>>> + break;
>>> + case 7:
>>> + *val = tsc2007_xfer(tsc,
>>> + (ADC_ON_12BIT | TSC2007_MEASURE_TEMP0));
>>> + break;
>>> + case 8:
>>> + *val = tsc2007_xfer(tsc,
>>> + (ADC_ON_12BIT | TSC2007_MEASURE_TEMP1));
>>> + break;
>>> + }
>>> +
>>> + /* Prepare for next touch reading - power down ADC, enable PENIRQ */
>>> + tsc2007_xfer(tsc, PWRDOWN);
>>> +
>>> + mutex_unlock(&tsc->mlock);
>>> +
>>> + ret = IIO_VAL_INT;
>>> +
>>> + return ret;
>>> +}
>>> +
>>> +static const struct iio_info tsc2007_iio_info = {
>>> + .read_raw = tsc2007_read_raw,
>>> + .driver_module = THIS_MODULE,
>>> +};
>>> +
>>> +int tsc2007_iio_configure(struct tsc2007 *ts)
>>> +{
>>> + int err;
>>> + struct iio_dev *indio_dev;
>>> + struct tsc2007_iio *iio;
>>> +
>>> + indio_dev = devm_iio_device_alloc(&ts->client->dev,
>>> + sizeof(struct tsc2007_iio));
>>> + if (!indio_dev) {
>>> + dev_err(&ts->client->dev, "iio_device_alloc failed\n");
>>> + return -ENOMEM;
>>> + }
>>> +
>>> + iio = iio_priv(indio_dev);
>>> + iio->ts = ts;
>>> + ts->iio_dev = (void *) indio_dev;
>>> +
>>> + indio_dev->name = "tsc2007";
>>> + indio_dev->dev.parent = &ts->client->dev;
>>> + indio_dev->info = &tsc2007_iio_info;
>>> + indio_dev->modes = INDIO_DIRECT_MODE;
>>> + indio_dev->channels = tsc2007_iio_channel;
>>> + indio_dev->num_channels = ARRAY_SIZE(tsc2007_iio_channel);
>>> +
>>> + err = iio_device_register(indio_dev);
>
> Changed this to devm.
>
>>> + if (err < 0) {
>>> + dev_err(&ts->client->dev, "iio_device_register() failed: %d\n",
>>> + err);
>>> + return err;
>>> + }
>>> +
>>> + return 0;
>>> +}
>>> +EXPORT_SYMBOL(tsc2007_iio_configure);
>
> This is not a separate module, there is no need to export this symbol.
>
>>> +
>>> +void tsc2007_iio_unconfigure(struct tsc2007 *ts)
>>> +{
>>> + struct iio_dev *indio_dev = ts->iio_dev;
>>> +
>>> + iio_device_unregister(indio_dev);
>>> +}
>>> +EXPORT_SYMBOL(tsc2007_iio_unconfigure);
>
> Dropped this as not needed with devm.
>
> --
> Dmitry