Hi Dmitry,
On 18-10-17 17:39, Dmitry Torokhov wrote:
> On Thu, Oct 18, 2018 at 01:31:53AM +0200, Marco Felsch wrote:
> > Hi Dmitry,
> >
> > thanks for your review.
> >
> > On 18-10-15 20:44, Dmitry Torokhov wrote:
> > > Hi Marco,
> > >
> > > On Mon, Sep 24, 2018 at 05:13:30PM +0200, Marco Felsch wrote:
> > > > Add initial support for the AT42QT1050 (QT1050) device. The device
> > > > supports up to five input keys, dependent on the mode. Since it adds only
> > > > the initial support the "1 to 4 keys plus Guard Channel" mode isn't
> > > > support.
> > > >
> > > > Signed-off-by: Marco Felsch <m.felsch@xxxxxxxxxxxxxx>
> > > > ---
> > > > .../bindings/input/microchip,qt1050.txt | 54 ++
> > > > drivers/input/keyboard/Kconfig | 11 +
> > > > drivers/input/keyboard/Makefile | 1 +
> > > > drivers/input/keyboard/qt1050.c | 589 ++++++++++++++++++
> > > > 4 files changed, 655 insertions(+)
> > > > create mode 100644 Documentation/devicetree/bindings/input/microchip,qt1050.txt
> > > > create mode 100644 drivers/input/keyboard/qt1050.c
> > > >
> > > > diff --git a/Documentation/devicetree/bindings/input/microchip,qt1050.txt b/Documentation/devicetree/bindings/input/microchip,qt1050.txt
> > > > new file mode 100644
> > > > index 000000000000..d63e286f6526
> > > > --- /dev/null
> > > > +++ b/Documentation/devicetree/bindings/input/microchip,qt1050.txt
> > > > @@ -0,0 +1,54 @@
> > > > +Microchip AT42QT1050 Five-channel Touch Sensor IC
> > > > +
> > > > +The AT42QT1050 (QT1050) is a QTouchADC sensor driver. The device can sense from
> > > > +one to five keys, dependent on mode. The QT1050 includes all signal processing
> > > > +functions necessary to provide stable sensing under a wide variety of changing
> > > > +conditions, and the outputs are fully debounced.
> > > > +
> > > > +The touchkey device node should be placed inside an I2C bus node.
> > > > +
> > > > +Required properties:
> > > > +- compatible: Must be "microchip,qt1050"
> > > > +- reg: The I2C address of the touchkeys
> > > > +- interrupts: The sink for the touchpad's IRQ output,
> > > > + see ../interrupt-controller/interrupts.txt
> > > > +- linux,keycodes: Specifies an array of numeric keycode values to be used for
> > > > + reporting button presses. The array can contain up to 5 entries. Array index
> > > > + 0 correspond to key 0 and so on. If the keys aren't continuous the
> > > > + KEY_RESERVED must be used. Keys marked as KEY_RESERVED or not specified will
> > > > + be disabled.
> > > > +
> > > > +Optional properties:
> > > > +- pre-charge-time: Specifies an array of precharge times in ns for each touch
> > > > + pad. The value for each pad depend on the hardware layouts. If not specified
> > > > + or invalid values are specified the default value is taken.
> > > > + Valid value range [ns]: 0 - 637500; values must be a multiple of 2500;
> > > > + default is 0.
> > > > +- touchscreen-average-samples: Please see ../input/touchscreen/touchscreen.txt
> > > > + for more information. Unlike the general binding, this is an array to specify
> > > > + the samples for each pad. If not specified or invalid values are specified
> > > > + the default value is taken.
> > > > + Valid values: 1, 4, 16, 64, 256, 1024, 4096, 16384; default is 1.
> > > > +- touchscreen-pre-scaling: Please see ../input/touchscreen/touchscreen.txt for
> > > > + more information. Unlike the general binding, this is an array to specify the
> > > > + scaling factor for each pad. If not specified or invalid values are specified
> > > > + the default value is taken.
> > > > + Valid values: 1, 2, 4, 8, 16, 32, 64, 128; default is 1.
> > > > +- touchscreen-fuzz-pressure: Please see ../input/touchscreen/touchscreen.txt for
> > > > + more information. Unlike the general binding, this is an array to specify the
> > > > + noise (threshold) value for each pad. If not specified or invalid values are
> > > > + specified the default value is taken.
> > >
> > > I am confused why we refer to touchscreen bindings here... Yes, the
> > > device is a capacitive touch sensor, but it it not a touchscreen
> > > controller. I think referring to generic touchscreen binding is
> > > confusing. Especially since they even do not map to the generic binding
> > > (list vs scalar value).
> >
> > Yes I'm deliberated about that too. I'm with you it isn't touchscreen
> > controller and you're right the driver accepts arrays, but the meaning
> > of the bindings map 1:1
>
> Not quite. For example, in input fuzz is used to "smooth out" the
> readings (see input_defuzz_abs_event) and not a threshhold (which it
> seems to be from the name in the driver). And I have no idea what
> "touchscreen-pre-scaling" is as it is not in my tree...
>
> > and I wouldn't introduce new vendor-specific
> > bindings.
>
> I think vendor-neutral bindings only make sense if the meaning and the
> type of data (and devices) are the same. I.e. if we have and IIO
> pressure meter device it should not be using touchscreen-fuzz-pressure
> even though device is dealing with pressure.
Okay I will change that to device specific bindings.
> > Rob what do you think about that? Should I replace it by:
> >
> > s/touchscreen-/microchip,touch-/
> >
> > > > + Valid value range: 0 - 255; default is 20.
> > > > +
> > > > +Example:
> > > > +QT1050 with 3 non continuous key, key3 and key5 are disabled.
> > > > +
> > > > +touchkeys@41 {
> > > > + compatible = "microchip,qt1050";
> > > > + reg = <0x41>;
> > > > + interrupt-parent = <&gpio0>;
> > > > + interrupts = <17 IRQ_TYPE_EDGE_FALLING>;
> > > > + linux,keycodes = <KEY_UP>, <KEY_RIGHT>, <KEY_RESERVED>, <KEY_DOWN>;
> > > > + touchscreen-average-samples = <64>, <64>, <64>, <256>;
> > > > + touchscreen-pre-scaling = <16>, <8>, <16>, <16>;
> > > > +};
> > > > diff --git a/drivers/input/keyboard/Kconfig b/drivers/input/keyboard/Kconfig
> > > > index 4713957b0cbb..08aba5e7cd93 100644
> > > > --- a/drivers/input/keyboard/Kconfig
> > > > +++ b/drivers/input/keyboard/Kconfig
> > > > @@ -137,6 +137,17 @@ config KEYBOARD_ATKBD_RDI_KEYCODES
> > > > right-hand column will be interpreted as the key shown in the
> > > > left-hand column.
> > > >
> > > > +config KEYBOARD_QT1050
> > > > + tristate "Microchip AT42QT1050 Touch Sensor Chip"
> > > > + depends on I2C
> > > > + select REGMAP_I2C
> > > > + help
> > > > + Say Y here if you want to use Microchip AT42QT1050 QTouch
> > > > + Sensor chip as input device.
> > > > +
> > > > + To compile this driver as a module, choose M here:
> > > > + the module will be called qt1050
> > > > +
> > > > config KEYBOARD_QT1070
> > > > tristate "Atmel AT42QT1070 Touch Sensor Chip"
> > > > depends on I2C
> > > > diff --git a/drivers/input/keyboard/Makefile b/drivers/input/keyboard/Makefile
> > > > index 182e92985dbf..f0291ca39f62 100644
> > > > --- a/drivers/input/keyboard/Makefile
> > > > +++ b/drivers/input/keyboard/Makefile
> > > > @@ -50,6 +50,7 @@ obj-$(CONFIG_KEYBOARD_OPENCORES) += opencores-kbd.o
> > > > obj-$(CONFIG_KEYBOARD_PMIC8XXX) += pmic8xxx-keypad.o
> > > > obj-$(CONFIG_KEYBOARD_PXA27x) += pxa27x_keypad.o
> > > > obj-$(CONFIG_KEYBOARD_PXA930_ROTARY) += pxa930_rotary.o
> > > > +obj-$(CONFIG_KEYBOARD_QT1050) += qt1050.o
> > > > obj-$(CONFIG_KEYBOARD_QT1070) += qt1070.o
> > > > obj-$(CONFIG_KEYBOARD_QT2160) += qt2160.o
> > > > obj-$(CONFIG_KEYBOARD_SAMSUNG) += samsung-keypad.o
> > > > diff --git a/drivers/input/keyboard/qt1050.c b/drivers/input/keyboard/qt1050.c
> > > > new file mode 100644
> > > > index 000000000000..80415586955d
> > > > --- /dev/null
> > > > +++ b/drivers/input/keyboard/qt1050.c
> > > > @@ -0,0 +1,589 @@
> > > > +// SPDX-License-Identifier: GPL-2.0
> > > > +/*
> > > > + * Microchip AT42QT1050 QTouch Sensor Controller
> > > > + *
> > > > + * Authors: Marco Felsch <kernel@xxxxxxxxxxxxxx>
> > > > + *
> > > > + * Base on AT42QT1070 driver by:
> > > > + * Bo Shen <voice.shen@xxxxxxxxx>
> > > > + * Copyright (C) 2011 Atmel
> > > > + */
> > > > +
> > > > +#include <linux/delay.h>
> > > > +#include <linux/i2c.h>
> > > > +#include <linux/input.h>
> > > > +#include <linux/interrupt.h>
> > > > +#include <linux/kernel.h>
> > > > +#include <linux/log2.h>
> > > > +#include <linux/module.h>
> > > > +#include <linux/of.h>
> > > > +#include <linux/regmap.h>
> > > > +
> > > > +/* Chip ID */
> > > > +#define QT1050_CHIP_ID 0x00
> > > > +#define QT1050_CHIP_ID_VER 0x46
> > > > +
> > > > +/* Firmware version */
> > > > +#define QT1050_FW_VERSION 0x01
> > > > +
> > > > +/* Detection status */
> > > > +#define QT1050_DET_STATUS 0x02
> > > > +
> > > > +/* Key status */
> > > > +#define QT1050_KEY_STATUS 0x03
> > > > +
> > > > +/* Key Signals */
> > > > +#define QT1050_KEY_SIGNAL_0_MSB 0x06
> > > > +#define QT1050_KEY_SIGNAL_0_LSB 0x07
> > > > +#define QT1050_KEY_SIGNAL_1_MSB 0x08
> > > > +#define QT1050_KEY_SIGNAL_1_LSB 0x09
> > > > +#define QT1050_KEY_SIGNAL_2_MSB 0x0c
> > > > +#define QT1050_KEY_SIGNAL_2_LSB 0x0d
> > > > +#define QT1050_KEY_SIGNAL_3_MSB 0x0e
> > > > +#define QT1050_KEY_SIGNAL_3_LSB 0x0f
> > > > +#define QT1050_KEY_SIGNAL_4_MSB 0x10
> > > > +#define QT1050_KEY_SIGNAL_4_LSB 0x11
> > > > +
> > > > +/* Reference data */
> > > > +#define QT1050_REF_DATA_0_MSB 0x14
> > > > +#define QT1050_REF_DATA_0_LSB 0x15
> > > > +#define QT1050_REF_DATA_1_MSB 0x16
> > > > +#define QT1050_REF_DATA_1_LSB 0x17
> > > > +#define QT1050_REF_DATA_2_MSB 0x1a
> > > > +#define QT1050_REF_DATA_2_LSB 0x1b
> > > > +#define QT1050_REF_DATA_3_MSB 0x1c
> > > > +#define QT1050_REF_DATA_3_LSB 0x1d
> > > > +#define QT1050_REF_DATA_4_MSB 0x1e
> > > > +#define QT1050_REF_DATA_4_LSB 0x1f
> > > > +
> > > > +/* Negative threshold level */
> > > > +#define QT1050_NTHR_0 0x21
> > > > +#define QT1050_NTHR_1 0x22
> > > > +#define QT1050_NTHR_2 0x24
> > > > +#define QT1050_NTHR_3 0x25
> > > > +#define QT1050_NTHR_4 0x26
> > > > +
> > > > +/* Pulse / Scale */
> > > > +#define QT1050_PULSE_SCALE_0 0x28
> > > > +#define QT1050_PULSE_SCALE_1 0x29
> > > > +#define QT1050_PULSE_SCALE_2 0x2b
> > > > +#define QT1050_PULSE_SCALE_3 0x2c
> > > > +#define QT1050_PULSE_SCALE_4 0x2d
> > > > +
> > > > +/* Detection integrator counter / AKS */
> > > > +#define QT1050_DI_AKS_0 0x2f
> > > > +#define QT1050_DI_AKS_1 0x30
> > > > +#define QT1050_DI_AKS_2 0x32
> > > > +#define QT1050_DI_AKS_3 0x33
> > > > +#define QT1050_DI_AKS_4 0x34
> > > > +
> > > > +/* Charge Share Delay */
> > > > +#define QT1050_CSD_0 0x36
> > > > +#define QT1050_CSD_1 0x37
> > > > +#define QT1050_CSD_2 0x39
> > > > +#define QT1050_CSD_3 0x3a
> > > > +#define QT1050_CSD_4 0x3b
> > > > +
> > > > +/* Low Power Mode */
> > > > +#define QT1050_LPMODE 0x3d
> > > > +
> > > > +/* Calibration and Reset */
> > > > +#define QT1050_RES_CAL 0x3f
> > > > +#define QT1050_RES_CAL_RESET BIT(7)
> > > > +#define QT1050_RES_CAL_CALIBRATE BIT(1)
> > > > +
> > > > +#define QT1050_MAX_KEYS 5
> > > > +#define QT1050_RESET_TIME 255
> > > > +
> > > > +struct qt1050_key {
> > > > + u32 charge_delay;
> > > > + u32 thr_cnt;
> > > > + u32 samples;
> > > > + u32 scale;
> > > > + u16 keycode;
> > > > +};
> > > > +
> > > > +struct qt1050_priv {
> > > > + struct i2c_client *client;
> > > > + struct input_dev *input;
> > > > + struct regmap *regmap;
> > > > + struct qt1050_key keys[QT1050_MAX_KEYS];
> > > > + unsigned short keycodes[QT1050_MAX_KEYS];
> > > > + u8 last_keys;
> > > > +};
> > > > +
> > > > +static bool qt1050_volatile_reg(struct device *dev, unsigned int reg)
> > > > +{
> > > > + switch (reg) {
> > > > + case QT1050_DET_STATUS:
> > > > + case QT1050_KEY_STATUS:
> > > > + case QT1050_KEY_SIGNAL_0_MSB:
> > > > + case QT1050_KEY_SIGNAL_0_LSB:
> > > > + case QT1050_KEY_SIGNAL_1_MSB:
> > > > + case QT1050_KEY_SIGNAL_1_LSB:
> > > > + case QT1050_KEY_SIGNAL_2_MSB:
> > > > + case QT1050_KEY_SIGNAL_2_LSB:
> > > > + case QT1050_KEY_SIGNAL_3_MSB:
> > > > + case QT1050_KEY_SIGNAL_3_LSB:
> > > > + case QT1050_KEY_SIGNAL_4_MSB:
> > > > + case QT1050_KEY_SIGNAL_4_LSB:
> > > > + return true;
> > > > + default:
> > > > + return false;
> > > > + }
> > > > +}
> > > > +
> > > > +static const struct regmap_range qt1050_readable_ranges[] = {
> > > > + regmap_reg_range(QT1050_CHIP_ID, QT1050_KEY_STATUS),
> > > > + regmap_reg_range(QT1050_KEY_SIGNAL_0_MSB, QT1050_KEY_SIGNAL_1_LSB),
> > > > + regmap_reg_range(QT1050_KEY_SIGNAL_2_MSB, QT1050_KEY_SIGNAL_4_LSB),
> > > > + regmap_reg_range(QT1050_REF_DATA_0_MSB, QT1050_REF_DATA_1_LSB),
> > > > + regmap_reg_range(QT1050_REF_DATA_2_MSB, QT1050_REF_DATA_4_LSB),
> > > > + regmap_reg_range(QT1050_NTHR_0, QT1050_NTHR_1),
> > > > + regmap_reg_range(QT1050_NTHR_2, QT1050_NTHR_4),
> > > > + regmap_reg_range(QT1050_PULSE_SCALE_0, QT1050_PULSE_SCALE_1),
> > > > + regmap_reg_range(QT1050_PULSE_SCALE_2, QT1050_PULSE_SCALE_4),
> > > > + regmap_reg_range(QT1050_DI_AKS_0, QT1050_DI_AKS_1),
> > > > + regmap_reg_range(QT1050_DI_AKS_2, QT1050_DI_AKS_4),
> > > > + regmap_reg_range(QT1050_CSD_0, QT1050_CSD_1),
> > > > + regmap_reg_range(QT1050_CSD_2, QT1050_RES_CAL),
> > > > +};
> > > > +
> > > > +static const struct regmap_access_table qt1050_readable_table = {
> > > > + .yes_ranges = qt1050_readable_ranges,
> > > > + .n_yes_ranges = ARRAY_SIZE(qt1050_readable_ranges),
> > > > +};
> > > > +
> > > > +static const struct regmap_range qt1050_writeable_ranges[] = {
> > > > + regmap_reg_range(QT1050_NTHR_0, QT1050_NTHR_1),
> > > > + regmap_reg_range(QT1050_NTHR_2, QT1050_NTHR_4),
> > > > + regmap_reg_range(QT1050_PULSE_SCALE_0, QT1050_PULSE_SCALE_1),
> > > > + regmap_reg_range(QT1050_PULSE_SCALE_2, QT1050_PULSE_SCALE_4),
> > > > + regmap_reg_range(QT1050_DI_AKS_0, QT1050_DI_AKS_1),
> > > > + regmap_reg_range(QT1050_DI_AKS_2, QT1050_DI_AKS_4),
> > > > + regmap_reg_range(QT1050_CSD_0, QT1050_CSD_1),
> > > > + regmap_reg_range(QT1050_CSD_2, QT1050_RES_CAL),
> > > > +};
> > > > +
> > > > +static const struct regmap_access_table qt1050_writeable_table = {
> > > > + .yes_ranges = qt1050_writeable_ranges,
> > > > + .n_yes_ranges = ARRAY_SIZE(qt1050_writeable_ranges),
> > > > +};
> > > > +
> > > > +static struct regmap_config qt1050_regmap_config = {
> > > > + .reg_bits = 8,
> > > > + .val_bits = 8,
> > > > + .max_register = QT1050_RES_CAL,
> > > > +
> > > > + .cache_type = REGCACHE_RBTREE,
> > > > +
> > > > + .wr_table = &qt1050_writeable_table,
> > > > + .rd_table = &qt1050_readable_table,
> > > > + .volatile_reg = qt1050_volatile_reg,
> > > > +};
> > > > +
> > > > +static bool qt1050_identify(struct qt1050_priv *ts)
> > > > +{
> > > > + unsigned int val;
> > > > +
> > > > + /* Read Chip ID */
> > > > + regmap_read(ts->regmap, QT1050_CHIP_ID, &val);
> > > > + if (val != QT1050_CHIP_ID_VER) {
> > > > + dev_err(&ts->client->dev, "ID %d not supported\n", val);
> > > > + return false;
> > > > + }
> > > > +
> > > > + /* Read firmware version */
> > > > + regmap_read(ts->regmap, QT1050_FW_VERSION, &val);
> > > > + if (val < 0) {
> > > > + dev_err(&ts->client->dev, "could not read the firmware version\n");
> > > > + return false;
> > > > + }
> > > > +
> > > > + dev_info(&ts->client->dev, "AT42QT1050 firmware version %1d.%1d\n",
> > > > + val >> 4, val & 0xf);
> > > > +
> > > > + return true;
> > > > +}
> > > > +
> > > > +static irqreturn_t qt1050_irq_threaded(int irq, void *dev_id)
> > > > +{
> > > > + struct qt1050_priv *ts = dev_id;
> > > > + struct input_dev *input = ts->input;
> > > > + unsigned long new_keys, changed;
> > > > + unsigned int val;
> > > > + int i, err;
> > > > +
> > > > + /* Read the detected status register, thus clearing interrupt */
> > > > + err = regmap_read(ts->regmap, QT1050_DET_STATUS, &val);
> > > > + if (err) {
> > > > + dev_err(&ts->client->dev, "Fail to read detection status: %d\n",
> > > > + err);
> > > > + return IRQ_NONE;
> > > > + }
> > > > +
> > > > + /* Read which key changed, keys are not continuous */
> > > > + err = regmap_read(ts->regmap, QT1050_KEY_STATUS, &val);
> > > > + if (err) {
> > > > + dev_err(&ts->client->dev,
> > > > + "Fail to determine the key status: %d\n", err);
> > > > + return IRQ_NONE;
> > > > + }
> > > > + new_keys = (val & 0x70) >> 2 | (val & 0x6) >> 1;
> > > > + changed = ts->last_keys ^ new_keys;
> > > > +
> > > > + for_each_set_bit(i, &changed, 8) {
> > > > + input_report_key(input, ts->keycodes[i],
> > > > + test_bit(i, &new_keys));
> > > > + }
> > > > +
> > > > + ts->last_keys = new_keys;
> > > > + input_sync(input);
> > > > +
> > > > + return IRQ_HANDLED;
> > > > +}
> > > > +
> > > > +static int qt1050_disable_key(struct regmap *map, int number)
> > > > +{
> > > > + unsigned int reg;
> > > > +
> > > > + switch (number) {
> > > > + case 0:
> > > > + reg = QT1050_DI_AKS_0;
> > > > + break;
> > > > + case 1:
> > > > + reg = QT1050_DI_AKS_1;
> > > > + break;
> > > > + case 2:
> > > > + reg = QT1050_DI_AKS_2;
> > > > + break;
> > > > + case 3:
> > > > + reg = QT1050_DI_AKS_3;
> > > > + break;
> > > > + case 4:
> > > > + reg = QT1050_DI_AKS_4;
> > > > + break;
>
> I wonder if there is any value in doing
>
> reg = QT1050_DI_AKS_0 + i + (i > 2);
>
> and similarly for other registers.
Yes there is a gap in the register map and your approach is smart, but I
find my less error prone (i.e. it should be (i > 1)) and easier to read
it. Anyway I can change this if you find it better.
> > > > + }
> > > > +
> > > > + return regmap_update_bits(map, reg, 0xfc, 0x00);
> > > > +}
> > > > +
> > > > +#ifdef CONFIG_OF
> > > > +static int qt1050_set_dt_data(struct qt1050_priv *ts)
> > > > +{
> > > > + struct regmap *map = ts->regmap;
> > > > + struct qt1050_key *k;
> > > > + int i, err;
> > > > + unsigned int pulsc_reg, csd_reg, nthr_reg;
> > > > +
> > > > + for (i = 0; i < QT1050_MAX_KEYS; i++) {
> > > > + k = &ts->keys[i];
> > > > + /* disable all keys which are marked as KEY_RESERVED */
> > > > + if (k->keycode == KEY_RESERVED) {
> > > > + err = qt1050_disable_key(map, i);
> > > > + if (err)
> > > > + return err;
> > > > + continue;
> > > > + }
> > > > +
> > > > + switch (i) {
> > > > + case 0:
> > > > + pulsc_reg = QT1050_PULSE_SCALE_0;
> > > > + csd_reg = QT1050_CSD_0;
> > > > + nthr_reg = QT1050_NTHR_0;
> > > > + break;
> > > > + case 1:
> > > > + pulsc_reg = QT1050_PULSE_SCALE_1;
> > > > + csd_reg = QT1050_CSD_1;
> > > > + nthr_reg = QT1050_NTHR_1;
> > > > + break;
> > > > + case 2:
> > > > + pulsc_reg = QT1050_PULSE_SCALE_1;
>
> Should it be QT1050_PULSE_SCALE_2?
Yes, sorry my mistake.
> > > > + csd_reg = QT1050_CSD_2;
> > > > + nthr_reg = QT1050_NTHR_2;
> > > > + break;
> > > > + case 3:
> > > > + pulsc_reg = QT1050_PULSE_SCALE_3;
> > > > + csd_reg = QT1050_CSD_3;
> > > > + nthr_reg = QT1050_NTHR_3;
> > > > + break;
> > > > + case 4:
> > > > + pulsc_reg = QT1050_PULSE_SCALE_4;
> > > > + csd_reg = QT1050_CSD_4;
> > > > + nthr_reg = QT1050_NTHR_4;
> > > > + break;
> > > > + }
> > > > +
> > > > + err = regmap_write(map, pulsc_reg,
> > > > + (k->samples << 4) | (k->scale));
> > > > + if (err)
> > > > + return err;
> > > > + err = regmap_write(map, csd_reg, k->charge_delay);
> > > > + if (err)
> > > > + return err;
> > > > + err = regmap_write(map, nthr_reg, k->thr_cnt);
> > > > + if (err)
> > > > + return err;
> > > > + }
> > > > +
> > > > + return 0;
> > > > +}
> > > > +
> > > > +static int qt1050_parse_dt(struct qt1050_priv *ts)
> > > > +{
> > > > + struct device *dev = &ts->client->dev;
> > > > + struct device_node *node = dev->of_node;
> > > > + int ret, i, n_keys;
> > > > + u32 tmp[QT1050_MAX_KEYS];
> > > > +
> > > > + ret = of_property_read_variable_u32_array(node, "linux,keycodes",
> > > > + &tmp[0], 1,
> > > > + QT1050_MAX_KEYS);
> > > > +
> > > > + /*
> > > > + * remaining keys are mapped to KEY_RESERVED in case of
> > > > + * n_keys < QT1050_MAX_KEYS
> > > > + */
> > > > + n_keys = ret;
> > > > + for (i = 0; i < n_keys; i++) {
> > > > + if (tmp[i] >= KEY_MAX) {
> > > > + dev_err(dev, "wrong keycode 0x%x\n", tmp[i]);
> > > > + return -EINVAL;
> > > > + }
> > > > + ts->keys[i].keycode = (u16)tmp[i];
> > > > + }
> > > > +
> > > > + ret = of_property_read_variable_u32_array(node, "pre-charge-time",
> > > > + &tmp[0], 1, QT1050_MAX_KEYS);
> > > > + if (!IS_ERR_VALUE(ret)) {
> > > > + for (i = 0; i < QT1050_MAX_KEYS; i++) {
> > > > + if (i < n_keys && (tmp[i] % 2500 == 0))
> > > > + ts->keys[i].charge_delay = tmp[i] / 2500;
> > > > + else
> > > > + ts->keys[i].charge_delay = 0;
> > > > + }
> > > > + }
> > > > +
> > > > + ret = of_property_read_variable_u32_array(node,
> > > > + "touchscreen-average-samples",
> > > > + &tmp[0], 1, QT1050_MAX_KEYS);
> > > > + if (!IS_ERR_VALUE(ret)) {
> > > > + for (i = 0; i < QT1050_MAX_KEYS; i++) {
> > > > + if (i < n_keys && is_power_of_2(tmp[i]))
> > > > + ts->keys[i].samples = ilog2(tmp[i]);
> > > > + else
> > > > + ts->keys[i].samples = 0;
> > > > + }
> > > > + }
> > > > +
> > > > + ret = of_property_read_variable_u32_array(node,
> > > > + "touchscreen-pre-scaling",
> > > > + &tmp[0], 1, QT1050_MAX_KEYS);
> > > > + if (!IS_ERR_VALUE(ret)) {
> > > > + for (i = 0; i < QT1050_MAX_KEYS; i++) {
> > > > + if (i < n_keys && is_power_of_2(tmp[i]))
> > > > + ts->keys[i].scale = ilog2(tmp[i]);
> > > > + else
> > > > + ts->keys[i].scale = 0;
> > > > + }
> > > > + }
> > > > +
> > > > + ret = of_property_read_variable_u32_array(node,
> > > > + "touchscreen-fuzz-pressure",
> > > > + &tmp[0], 1, QT1050_MAX_KEYS);
> > > > + if (!IS_ERR_VALUE(ret))
> > > > + for (i = 0; i < QT1050_MAX_KEYS; i++)
> > > > + ts->keys[i].thr_cnt = i < n_keys ? tmp[i] : 20;
> > > > +
> > > > + return 0;
> > > > +}
> > > > +#endif
> > > > +
> > > > +static int qt1050_probe(struct i2c_client *client,
> > > > + const struct i2c_device_id *id)
> > > > +{
> > > > + struct qt1050_priv *ts;
> > > > + struct input_dev *input;
> > > > + struct device *dev = &client->dev;
> > > > + struct regmap *map;
> > > > + unsigned int status;
> > > > + int i;
> > > > + int err;
> > > > +
> > > > + /* Check basic functionality */
> > > > + err = i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE);
> > > > + if (!err) {
> > > > + dev_err(&client->dev, "%s adapter not supported\n",
> > > > + dev_driver_string(&client->adapter->dev));
> > > > + return -ENODEV;
> > > > + }
> > > > +
> > > > + if (!client->irq) {
> > > > + dev_err(dev, "assign a irq line to this device\n");
> > > > + return -EINVAL;
> > > > + }
> > > > +
> > > > + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
> > > > + input = devm_input_allocate_device(dev);
> > > > + if (!ts || !input) {
> > > > + dev_err(dev, "insufficient memory\n");
> > > > + return -ENOMEM;
> > > > + }
> > > > +
> > > > + map = devm_regmap_init_i2c(client, &qt1050_regmap_config);
> > > > + if (IS_ERR(map))
> > > > + return PTR_ERR(map);
> > > > +
> > > > + ts->client = client;
> > > > + ts->input = input;
> > > > + ts->regmap = map;
> > > > +
> > > > + i2c_set_clientdata(client, ts);
> > > > +
> > > > + /* Identify the qt1050 chip */
> > > > + if (!qt1050_identify(ts))
> > > > + return -ENODEV;
> > > > +
> > > > + if (IS_ENABLED(CONFIG_OF)) {
> > > > + err = qt1050_parse_dt(ts);
> > > > + if (err) {
> > > > + dev_err(dev, "Failed to parse dt: %d\n", err);
> > > > + return err;
> > > > + }
> > > > + } else {
> > > > + /* init each key with a valid code */
> > > > + for (i = 0; i < QT1050_MAX_KEYS; i++)
> > > > + ts->keys[i].keycode = KEY_1 + i;
> > > > + }
> > >
> > > I'd rather we used generic device properties (i.e.
> > > device_property_read_xxx() instead of of_property_read_xxx()) and did
> > > not provide this fallback.
> >
> > I'm with you, but I wanted to use the of_property_read_variable_*()
> > helpers, since all properties can distinguish in their array size.
> > Sure I can add a helper to reimplement that localy using the
> > device_property_read_xxx() functions. IMHO this will be a later on
> > feature, if the acpi guys needs this features too. Is that okay?
>
> Well, that is an argument for adding proper
> device_property_read_variable_*(). However, after lookign at the binding
> again, I wonder if you should not describe this as sub-nodes:
A device_property_read_variable_*() would be nice.
>
> touchkeys@41 {
> ...
> up@0 {
> reg = <0>;
> linux,code = <KEY_UP>;
> average-samples = <64>;
> pre-scaling = <16>;
> pressure-threshold = <...>;
> };
>
> right@1 {
> reg = <1>;
> linux,code = <KEY_RIGHT>;
> average-samples = <64>;
> pre-scaling = <8>;
> pressure-threshold = <2>;
> };
> ...
> };
>
> and then use device_for_each_child_node() to parse it.
That's a good approach, thanks. I wanted to be similar with the other
input bindings, which uses arrays for linux,code and scalar values for
other properties. Since the qt1050 can configure each pad differently
I used only arrays. Is it good to change the layout only for one deivce?
Maybe it would better to implement the device_property_read_variable_*()
helper.
> Thanks.
>
Regards,
Marco
