[PATCH v8 3/3] Input: Add TouchNetix axiom i2c touchscreen driver

Kamel Bouhara
2024-02-19T10:12:34Z

Add a new driver for the TouchNetix's axiom family of
touchscreen controllers. This driver only supports i2c
and can be later adapted for SPI and USB support.

Signed-off-by: Kamel Bouhara <kamel.bouhara@bootlin.com>
---
MAINTAINERS | 1 +
drivers/input/touchscreen/Kconfig | 12 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/touchnetix_axiom.c | 669 +++++++++++++++++++
4 files changed, 683 insertions(+)
create mode 100644 drivers/input/touchscreen/touchnetix_axiom.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 4b3ed2f22b89..de5fad8f317a 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -22262,6 +22262,7 @@ M: Kamel Bouhara <kamel.bouhara@bootlin.com>
L: linux-input@vger.kernel.org
S: Maintained
F: Documentation/devicetree/bindings/input/touchscreen/touchnetix,ax54a.yaml
+F: drivers/input/touchscreen/touchnetix_axiom.c

TPM DEVICE DRIVER
M: Peter Huewe <peterhuewe@gmx.de>
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index e3e2324547b9..f36bee8d8696 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -803,6 +803,18 @@ config TOUCHSCREEN_MIGOR
To compile this driver as a module, choose M here: the
module will be called migor_ts.

+config TOUCHSCREEN_TOUCHNETIX_AXIOM
+ tristate "TouchNetix AXIOM based touchscreen controllers"
+ depends on I2C
+ help
+ Say Y here if you have a axiom touchscreen connected to
+ your system.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called axiom.
+
config TOUCHSCREEN_TOUCHRIGHT
tristate "Touchright serial touchscreen"
select SERIO
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 62bd24f3ac8e..8e32a2df5e18 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -88,6 +88,7 @@ obj-$(CONFIG_TOUCHSCREEN_SUR40) += sur40.o
obj-$(CONFIG_TOUCHSCREEN_SURFACE3_SPI) += surface3_spi.o
obj-$(CONFIG_TOUCHSCREEN_TI_AM335X_TSC) += ti_am335x_tsc.o
obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213) += touchit213.o
+obj-$(CONFIG_TOUCHSCREEN_TOUCHNETIX_AXIOM) += touchnetix_axiom.o
obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT) += touchright.o
obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN) += touchwin.o
obj-$(CONFIG_TOUCHSCREEN_TS4800) += ts4800-ts.o
diff --git a/drivers/input/touchscreen/touchnetix_axiom.c b/drivers/input/touchscreen/touchnetix_axiom.c
new file mode 100644
index 000000000000..f7d1b23a4baf
--- /dev/null
+++ b/drivers/input/touchscreen/touchnetix_axiom.c
@@ -0,0 +1,669 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TouchNetix axiom Touchscreen Driver
+ *
+ * Copyright (C) 2020-2023 TouchNetix Ltd.
+ *
+ * Author(s): Bart Prescott <bartp@baasheep.co.uk>
+ * Pedro Torruella <pedro.torruella@touchnetix.com>
+ * Mark Satterthwaite <mark.satterthwaite@touchnetix.com>
+ * Hannah Rossiter <hannah.rossiter@touchnetix.com>
+ * Kamel Bouhara <kamel.bouhara@bootlin.com>
+ *
+ */
+#include <linux/bitfield.h>
+#include <linux/crc16.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/regmap.h>
+
+#include <asm/unaligned.h>
+#define AXIOM_PROX_LEVEL -128
+#define AXIOM_DMA_OPS_DELAY_USEC 250
+#define AXIOM_STARTUP_TIME_MS 110
+/*
+ * Register group u31 has 2 pages for usage table entries.
+ */
+#define AXIOM_U31_MAX_USAGES 0xff
+#define AXIOM_U31_BYTES_PER_USAGE 6
+#define AXIOM_U31_PAGE0_LENGTH 0x0C
+#define AXIOM_U31_BOOTMODE_MASK BIT(7)
+#define AXIOM_U31_DEVID_MASK GENMASK(14, 0)
+
+#define AXIOM_MAX_REPORT_LEN 0x7f
+
+#define AXIOM_CMD_HEADER_READ_MASK BIT(15)
+#define AXIOM_U41_MAX_TARGETS 10
+
+#define AXIOM_U46_AUX_CHANNELS 4
+#define AXIOM_U46_AUX_MASK GENMASK(11, 0)
+
+#define AXIOM_COMMS_MAX_USAGE_PAGES 3
+#define AXIOM_COMMS_PAGE_SIZE 256
+#define AXIOM_COMMS_REPORT_LEN_MASK GENMASK(6, 0)
+
+#define AXIOM_REPORT_USAGE_ID 0x34
+#define AXIOM_DEVINFO_USAGE_ID 0x31
+#define AXIOM_USAGE_2HB_REPORT_ID 0x01
+#define AXIOM_USAGE_2AUX_REPORT_ID 0x46
+#define AXIOM_USAGE_2DCTS_REPORT_ID 0x41
+
+#define AXIOM_PAGE_OFFSET_MASK GENMASK(6, 0)
+
+struct axiom_devinfo {
+ __le16 device_id;
+ u8 fw_minor;
+ u8 fw_major;
+ u8 fw_info_extra;
+ u8 tcp_revision;
+ u8 bootloader_fw_minor;
+ u8 bootloader_fw_major;
+ __le16 jedec_id;
+ u8 num_usages;
+} __packed;
+
+/*
+ * Describes parameters of a specific usage, essentially a single element of
+ * the "Usage Table"
+ */
+struct axiom_usage_entry {
+ u8 id;
+ u8 is_report;
+ u8 start_page;
+ u8 num_pages;
+};
+
+/*
+ * Represents state of a touch or target when detected prior to a touch (eg.
+ * hover or proximity events).
+ */
+enum axiom_target_state {
+ AXIOM_TARGET_STATE_NOT_PRESENT = 0,
+ AXIOM_TARGET_STATE_PROX = 1,
+ AXIOM_TARGET_STATE_HOVER = 2,
+ AXIOM_TARGET_STATE_TOUCHING = 3,
+};
+
+struct axiom_u41_target {
+ enum axiom_target_state state;
+ u16 x;
+ u16 y;
+ s8 z;
+ bool insert;
+ bool touch;
+};
+
+struct axiom_target_report {
+ u8 index;
+ u8 present;
+ u16 x;
+ u16 y;
+ s8 z;
+};
+
+struct axiom_cmd_header {
+ __le16 target_address;
+ __le16 length;
+} __packed;
+
+struct axiom_data {
+ struct axiom_devinfo devinfo;
+ struct device *dev;
+ struct gpio_desc *reset_gpio;
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ u32 max_report_len;
+ u8 rx_buf[AXIOM_COMMS_MAX_USAGE_PAGES * AXIOM_COMMS_PAGE_SIZE];
+ struct axiom_u41_target targets[AXIOM_U41_MAX_TARGETS];
+ struct axiom_usage_entry usage_table[AXIOM_U31_MAX_USAGES];
+ bool usage_table_populated;
+ struct regulator *vdda;
+ struct regulator *vddi;
+ struct regmap *regmap;
+ struct touchscreen_properties prop;
+};
+
+static const struct regmap_config axiom_i2c_regmap_config = {
+ .reg_bits = 32,
+ .reg_format_endian = REGMAP_ENDIAN_LITTLE,
+ .val_bits = 8,
+ .val_format_endian = REGMAP_ENDIAN_LITTLE,
+};
+
+/*
+ * axiom devices are typically configured to report touches at a rate
+ * of 100Hz (10ms) for systems that require polling for reports.
+ * When reports are polled, it will be expected to occasionally
+ * observe the overflow bit being set in the reports.
+ * This indicates that reports are not being read fast enough.
+ */
+#define POLL_INTERVAL_DEFAULT_MS 10
+
+/* Translate usage/page/offset triplet into physical address. */
+static u16 axiom_usage_to_target_address(struct axiom_data *ts, u8 usage, u8 page,
+ char offset)
+{
+ /* At the moment the convention is that u31 is always at physical address 0x0 */
+ if (!ts->usage_table_populated) {
+ if (usage == AXIOM_DEVINFO_USAGE_ID)
+ return ((page << 8) + offset);
+ else
+ return 0xffff;
+ }
+
+ if (page >= ts->usage_table[usage].num_pages) {
+ dev_err(ts->dev, "Invalid usage table! usage: u%02x, page: %02x, offset: %02x\n",
+ usage, page, offset);
+ return 0xffff;
+ }
+
+ return ((ts->usage_table[usage].start_page + page) << 8) + offset;
+}
+
+static int axiom_read(struct axiom_data *ts, u8 usage, u8 page, void *buf, u16 len)
+{
+ struct axiom_cmd_header cmd_header;
+ u32 preamble;
+ int ret;
+
+ cmd_header.target_address = cpu_to_le16(axiom_usage_to_target_address(ts, usage, page, 0));
+ cmd_header.length = cpu_to_le16(len | AXIOM_CMD_HEADER_READ_MASK);
+
+ preamble = get_unaligned_le32(&cmd_header);
+
+ ret = regmap_write(ts->regmap, preamble, 0);
+ if (ret) {
+ dev_err(ts->dev, "failed to write preamble, error %d\n", ret);
+ return ret;
+ }
+
+ ret = regmap_raw_read(ts->regmap, 0, buf, len);
+ if (ret) {
+ dev_err(ts->dev, "failed to read target address %04x, error %d\n",
+ cmd_header.target_address, ret);
+ return ret;
+ }
+
+ /* Wait device's DMA operations */
+ usleep_range(AXIOM_DMA_OPS_DELAY_USEC, AXIOM_DMA_OPS_DELAY_USEC + 50);
+
+ return 0;
+}
+
+/*
+ * One of the main purposes for reading the usage table is to identify
+ * which usages reside at which target address.
+ * When performing subsequent reads or writes to AXIOM, the target address
+ * is used to specify which usage is being accessed.
+ * Consider the following discovery code which will build up the usage table.
+ */
+static u32 axiom_populate_usage_table(struct axiom_data *ts)
+{
+ struct axiom_usage_entry *usage_table;
+ u8 *rx_data = ts->rx_buf;
+ u32 max_report_len = 0;
+ u32 usage_id;
+ int error;
+
+ usage_table = ts->usage_table;
+
+ /* Read the second page of usage u31 to get the usage table */
+ error = axiom_read(ts, AXIOM_DEVINFO_USAGE_ID, 1, rx_data,
+ (AXIOM_U31_BYTES_PER_USAGE * ts->devinfo.num_usages));
+
+ if (error)
+ return error;
+
+ for (usage_id = 0; usage_id < ts->devinfo.num_usages; usage_id++) {
+ u16 offset = (usage_id * AXIOM_U31_BYTES_PER_USAGE);
+ u8 id = rx_data[offset + 0];
+ u8 start_page = rx_data[offset + 1];
+ u8 num_pages = rx_data[offset + 2];
+ u32 max_offset = ((rx_data[offset + 3] & AXIOM_PAGE_OFFSET_MASK) + 1) * 2;
+
+ usage_table[id].is_report = !num_pages;
+
+ /* Store the entry into the usage table */
+ usage_table[id].id = id;
+ usage_table[id].start_page = start_page;
+ usage_table[id].num_pages = num_pages;
+
+ dev_dbg(ts->dev, "Usage u%02x Info: %*ph\n", id, AXIOM_U31_BYTES_PER_USAGE,
+ &rx_data[offset]);
+
+ /* Identify the max report length the module will receive */
+ if (usage_table[id].is_report && max_offset > max_report_len)
+ max_report_len = max_offset;
+ }
+
+ ts->usage_table_populated = true;
+
+ return max_report_len;
+}
+
+static int axiom_discover(struct axiom_data *ts)
+{
+ int error;
+
+ /*
+ * Fetch the first page of usage u31 to get the
+ * device information and the number of usages
+ */
+ error = axiom_read(ts, AXIOM_DEVINFO_USAGE_ID, 0, &ts->devinfo, AXIOM_U31_PAGE0_LENGTH);
+ if (error)
+ return error;
+
+ dev_dbg(ts->dev, " Boot Mode : %s\n",
+ FIELD_GET(AXIOM_U31_BOOTMODE_MASK,
+ le16_to_cpu(ts->devinfo.device_id)) ? "BLP" : "TCP");
+ dev_dbg(ts->dev, " Device ID : %04lx\n",
+ FIELD_GET(AXIOM_U31_DEVID_MASK, le16_to_cpu(ts->devinfo.device_id)));
+ dev_dbg(ts->dev, " Firmware Rev : %02x.%02x\n", ts->devinfo.fw_major,
+ ts->devinfo.fw_minor);
+ dev_dbg(ts->dev, " Bootloader Rev : %02x.%02x\n", ts->devinfo.bootloader_fw_major,
+ ts->devinfo.bootloader_fw_minor);
+ dev_dbg(ts->dev, " FW Extra Info : %04x\n", ts->devinfo.fw_info_extra);
+ dev_dbg(ts->dev, " Silicon : %04x\n", le16_to_cpu(ts->devinfo.jedec_id));
+ dev_dbg(ts->dev, " Number usages : %04x\n", ts->devinfo.num_usages);
+
+ ts->max_report_len = axiom_populate_usage_table(ts);
+ if (!ts->max_report_len || !ts->devinfo.num_usages ||
+ ts->max_report_len > AXIOM_MAX_REPORT_LEN) {
+ dev_err(ts->dev, "Invalid report length or usages number");
+ return -EINVAL;
+ }
+
+ dev_dbg(ts->dev, "Max Report Length: %u\n", ts->max_report_len);
+
+ return 0;
+}
+
+/*
+ * Support function to axiom_process_u41_report.
+ * Generates input-subsystem events for every target.
+ * After calling this function the caller shall issue
+ * a Sync to the input sub-system.
+ */
+static bool axiom_process_u41_report_target(struct axiom_data *ts,
+ struct axiom_target_report *target)
+{
+ struct input_dev *input_dev = ts->input_dev;
+ struct axiom_u41_target *target_prev_state;
+ enum axiom_target_state current_state;
+ int id;
+
+ /* Verify the target index */
+ if (target->index >= AXIOM_U41_MAX_TARGETS) {
+ dev_err(ts->dev, "Invalid target index! %u\n", target->index);
+ return false;
+ }
+
+ target_prev_state = &ts->targets[target->index];
+
+ current_state = AXIOM_TARGET_STATE_NOT_PRESENT;
+
+ if (target->present) {
+ if (target->z >= 0)
+ current_state = AXIOM_TARGET_STATE_TOUCHING;
+ else if (target->z > AXIOM_PROX_LEVEL && target->z < 0)
+ current_state = AXIOM_TARGET_STATE_HOVER;
+ else if (target->z == AXIOM_PROX_LEVEL)
+ current_state = AXIOM_TARGET_STATE_PROX;
+ }
+
+ if (target_prev_state->state == current_state &&
+ target_prev_state->x == target->x &&
+ target_prev_state->y == target->y &&
+ target_prev_state->z == target->z)
+ return false;
+
+ id = target->index;
+
+ dev_dbg(ts->dev, "U41 Target T%u, slot:%u present:%u, x:%u, y:%u, z:%d\n",
+ target->index, slot, target->present,
+ target->x, target->y, target->z);
+
+ switch (current_state) {
+ case AXIOM_TARGET_STATE_NOT_PRESENT:
+ case AXIOM_TARGET_STATE_PROX:
+ if (!target_prev_state->insert)
+ break;
+ target_prev_state->insert = false;
+
+ if (!id)
+ input_report_key(input_dev, BTN_TOUCH, 0);
+
+ input_mt_report_slot_inactive(input_dev);
+ /*
+ * make sure the previous coordinates are
+ * all off screen when the finger comes back
+ */
+ target->x = 65535;
+ target->y = 65535;
+ target->z = AXIOM_PROX_LEVEL;
+ break;
+ case AXIOM_TARGET_STATE_HOVER:
+ case AXIOM_TARGET_STATE_TOUCHING:
+ target_prev_state->insert = true;
+ input_report_abs(input_dev, ABS_MT_TRACKING_ID, id);
+ input_report_abs(input_dev, ABS_MT_POSITION_X, target->x);
+ input_report_abs(input_dev, ABS_MT_POSITION_Y, target->y);
+
+ if (current_state == AXIOM_TARGET_STATE_TOUCHING) {
+ input_report_abs(input_dev, ABS_MT_DISTANCE, 0);
+ input_report_abs(input_dev, ABS_DISTANCE, 0);
+ input_report_abs(input_dev, ABS_MT_PRESSURE, target->z);
+ input_report_abs(input_dev, ABS_PRESSURE, target->z);
+ } else {
+ input_report_abs(input_dev, ABS_MT_DISTANCE, -target->z);
+ input_report_abs(input_dev, ABS_DISTANCE, -target->z);
+ input_report_abs(input_dev, ABS_MT_PRESSURE, 0);
+ input_report_abs(input_dev, ABS_PRESSURE, 0);
+ }
+
+ if (!id)
+ input_report_key(input_dev, BTN_TOUCH, (current_state ==
+ AXIOM_TARGET_STATE_TOUCHING));
+ break;
+ default:
+ break;
+ }
+
+ target_prev_state->state = current_state;
+ target_prev_state->x = target->x;
+ target_prev_state->y = target->y;
+ target_prev_state->z = target->z;
+
+ return true;
+}
+
+/*
+ * U41 is the output report of the 2D CTS and contains the status of targets
+ * (including contacts and pre-contacts) along with their X,Y,Z values.
+ * When a target has been removed (no longer detected),
+ * the corresponding X,Y,Z values will be zeroed.
+ */
+static bool axiom_process_u41_report(struct axiom_data *ts, u8 *rx_buf)
+{
+ struct axiom_target_report target;
+ bool update_done = false;
+ u16 target_status;
+ int i;
+
+ target_status = get_unaligned_le16(rx_buf + 1);
+
+ for (i = 0; i < AXIOM_U41_MAX_TARGETS; i++) {
+ u8 *target_step = &rx_buf[i * 4];
+
+ target.index = i;
+ input_mt_slot(ts->input_dev, i);
+ input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
+ target.present = ((target_status & (1 << i)) != 0) ? 1 : 0;
+ target.x = get_unaligned_le16(target_step + 3);
+ target.y = get_unaligned_le16(target_step + 5);
+ target.z = (s8)(rx_buf[i + 43]);
+ touchscreen_report_pos(ts->input_dev, &ts->prop, target.x, target.y, true);
+ update_done |= axiom_process_u41_report_target(ts, &target);
+ }
+
+ return update_done;
+}
+
+/*
+ * U46 report contains a low level measurement data generated by the capacitive
+ * displacement sensor (CDS) algorithms from the auxiliary channels.
+ * This information is useful when tuning multi-press to assess mechanical
+ * consistency in the unit's construction.
+ */
+static void axiom_process_u46_report(struct axiom_data *ts, u8 *rx_buf)
+{
+ struct input_dev *input_dev = ts->input_dev;
+ u32 event_value;
+ u16 aux_value;
+ int i;
+
+ for (i = 0; i < AXIOM_U46_AUX_CHANNELS; i++) {
+ u8 *target_step = &rx_buf[i * 2];
+
+ input_mt_slot(input_dev, i);
+ input_mt_report_slot_state(input_dev, MT_TOOL_FINGER, true);
+ aux_value = get_unaligned_le16(target_step + 1) & AXIOM_U46_AUX_MASK;
+ event_value = (i << 16) | (aux_value);
+ input_event(input_dev, EV_MSC, MSC_RAW, event_value);
+ }
+}
+
+/*
+ * Validates the crc and demultiplexes the axiom reports to the appropriate
+ * report handler
+ */
+static int axiom_handle_events(struct axiom_data *ts)
+{
+ struct input_dev *input_dev = ts->input_dev;
+ u8 *report_data = ts->rx_buf;
+ struct device *dev = ts->dev;
+ u16 crc_report;
+ u8 *crc_bytes;
+ u16 crc_calc;
+ int error;
+ u8 len;
+
+ error = axiom_read(ts, AXIOM_REPORT_USAGE_ID, 0, report_data, ts->max_report_len);
+ if (error)
+ return error;
+
+ len = (report_data[0] & AXIOM_COMMS_REPORT_LEN_MASK) << 1;
+ if (len <= 2) {
+ dev_err(dev, "Zero length report discarded.\n");
+ return -ENODATA;
+ }
+
+ /* Validate the report CRC */
+ crc_bytes = &report_data[len];
+
+ crc_report = get_unaligned_le16(crc_bytes - 2);
+ /* Length is in 16 bit words and remove the size of the CRC16 itself */
+ crc_calc = crc16(0, report_data, (len - 2));
+
+ if (crc_calc != crc_report) {
+ dev_err(dev,
+ "CRC mismatch! Expected: %#x, Calculated CRC: %#x.\n",
+ crc_report, crc_calc);
+ return -EINVAL;
+ }
+
+ switch (report_data[1]) {
+ case AXIOM_USAGE_2DCTS_REPORT_ID:
+ if (axiom_process_u41_report(ts, &report_data[1])) {
+ input_mt_sync_frame(input_dev);
+ input_sync(input_dev);
+ }
+ break;
+
+ case AXIOM_USAGE_2AUX_REPORT_ID:
+ /* This is an aux report (force) */
+ axiom_process_u46_report(ts, &report_data[1]);
+ input_mt_sync(input_dev);
+ input_sync(input_dev);
+ break;
+
+ case AXIOM_USAGE_2HB_REPORT_ID:
+ /* This is a heartbeat report */
+ break;
+ default:
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+static void axiom_i2c_poll(struct input_dev *input_dev)
+{
+ struct axiom_data *ts = input_get_drvdata(input_dev);
+
+ axiom_handle_events(ts);
+}
+
+static irqreturn_t axiom_irq(int irq, void *dev_id)
+{
+ struct axiom_data *ts = dev_id;
+
+ axiom_handle_events(ts);
+
+ return IRQ_HANDLED;
+}
+
+static void axiom_reset(struct gpio_desc *reset_gpio)
+{
+ gpiod_set_value_cansleep(reset_gpio, 1);
+ usleep_range(1000, 2000);
+ gpiod_set_value_cansleep(reset_gpio, 0);
+ msleep(AXIOM_STARTUP_TIME_MS);
+}
+
+static int axiom_i2c_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct input_dev *input_dev;
+ struct axiom_data *ts;
+ u32 poll_interval;
+ int target;
+ int error;
+
+ ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ i2c_set_clientdata(client, ts);
+ ts->client = client;
+ ts->dev = dev;
+
+ ts->regmap = devm_regmap_init_i2c(client, &axiom_i2c_regmap_config);
+ error = PTR_ERR_OR_ZERO(ts->regmap);
+ if (error) {
+ dev_err(dev, "Failed to initialize regmap: %d\n", error);
+ return error;
+ }
+
+ ts->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ts->reset_gpio))
+ return dev_err_probe(dev, PTR_ERR(ts->reset_gpio), "failed to get reset GPIO\n");
+
+ if (ts->reset_gpio)
+ axiom_reset(ts->reset_gpio);
+
+ ts->vddi = devm_regulator_get_optional(dev, "vddi");
+ if (!IS_ERR(ts->vddi)) {
+ error = devm_regulator_get_enable(dev, "vddi");
+ if (error)
+ return dev_err_probe(&client->dev, error,
+ "Failed to enable vddi regulator\n");
+ }
+
+ ts->vdda = devm_regulator_get_optional(dev, "vdda");
+ if (!IS_ERR(ts->vdda)) {
+ error = devm_regulator_get_enable(dev, "vdda");
+ if (error)
+ return dev_err_probe(&client->dev, error,
+ "Failed to enable vdda regulator\n");
+ msleep(AXIOM_STARTUP_TIME_MS);
+ }
+
+ error = axiom_discover(ts);
+ if (error)
+ return dev_err_probe(dev, error, "Failed touchscreen discover\n");
+
+ input_dev = devm_input_allocate_device(ts->dev);
+ if (!input_dev)
+ return -ENOMEM;
+
+ input_dev->name = "TouchNetix axiom Touchscreen";
+ input_dev->phys = "input/axiom_ts";
+
+ input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0, 65535, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0, 65535, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_TOOL_TYPE, 0, MT_TOOL_MAX, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_DISTANCE, 0, 127, 0, 0);
+ input_set_abs_params(input_dev, ABS_MT_PRESSURE, 0, 127, 0, 0);
+
+ touchscreen_parse_properties(input_dev, true, &ts->prop);
+
+ /* Registers the axiom device as a touchscreen instead of a mouse pointer */
+ error = input_mt_init_slots(input_dev, AXIOM_U41_MAX_TARGETS, INPUT_MT_DIRECT);
+ if (error)
+ return error;
+
+ /* Enables the raw data for up to 4 force channels to be sent to the input subsystem */
+ set_bit(EV_REL, input_dev->evbit);
+ set_bit(EV_MSC, input_dev->evbit);
+ /* Declare that we support "RAW" Miscellaneous events */
+ set_bit(MSC_RAW, input_dev->mscbit);
+
+ ts->input_dev = input_dev;
+ input_set_drvdata(ts->input_dev, ts);
+
+ /* Ensure that all reports are initialised to not be present. */
+ for (target = 0; target < AXIOM_U41_MAX_TARGETS; target++)
+ ts->targets[target].state = AXIOM_TARGET_STATE_NOT_PRESENT;
+
+ error = devm_request_threaded_irq(dev, client->irq, NULL,
+ axiom_irq, IRQF_ONESHOT, dev_name(dev), ts);
+ if (error) {
+ dev_info(dev, "Request irq failed, falling back to polling mode");
+
+ error = input_setup_polling(input_dev, axiom_i2c_poll);
+ if (error)
+ return dev_err_probe(ts->dev, error, "Unable to set up polling mode\n");
+
+ if (!device_property_read_u32(ts->dev, "poll-interval", &poll_interval))
+ input_set_poll_interval(input_dev, poll_interval);
+ else
+ input_set_poll_interval(input_dev, POLL_INTERVAL_DEFAULT_MS);
+ }
+
+ error = input_register_device(input_dev);
+ if (error)
+ return dev_err_probe(ts->dev, error,
+ "Could not register with Input Sub-system.\n");
+
+ return 0;
+}
+
+static const struct i2c_device_id axiom_i2c_id_table[] = {
+ { "ax54a" },
+ { },
+};
+MODULE_DEVICE_TABLE(i2c, axiom_i2c_id_table);
+
+static const struct of_device_id axiom_i2c_of_match[] = {
+ { .compatible = "touchnetix,ax54a", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, axiom_i2c_of_match);
+
+static struct i2c_driver axiom_i2c_driver = {
+ .driver = {
+ .name = "axiom",
+ .of_match_table = axiom_i2c_of_match,
+ },
+ .id_table = axiom_i2c_id_table,
+ .probe = axiom_i2c_probe,
+};
+module_i2c_driver(axiom_i2c_driver);
+
+MODULE_AUTHOR("Bart Prescott <bartp@baasheep.co.uk>");
+MODULE_AUTHOR("Pedro Torruella <pedro.torruella@touchnetix.com>");
+MODULE_AUTHOR("Mark Satterthwaite <mark.satterthwaite@touchnetix.com>");
+MODULE_AUTHOR("Hannah Rossiter <hannah.rossiter@touchnetix.com>");
+MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@bootlin.com>");
+MODULE_DESCRIPTION("TouchNetix axiom touchscreen I2C bus driver");
+MODULE_LICENSE("GPL");
--
2.25.1