Add a new driver for the TouchNetix's aXiom family of
multi-touch controller. This driver only support i2c
and can be later adapted for SPI and USB support.
Signed-off-by: Kamel Bouhara <kamel.bouhara@xxxxxxxxxxx>
---
.../devicetree/bindings/vendor-prefixes.yaml | 2 +
MAINTAINERS | 7 +
drivers/input/touchscreen/Kconfig | 11 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/axiom_core.c | 382 ++++++++++++++++++
drivers/input/touchscreen/axiom_core.h | 140 +++++++
drivers/input/touchscreen/axiom_i2c.c | 349 ++++++++++++++++
7 files changed, 892 insertions(+)
create mode 100644 drivers/input/touchscreen/axiom_core.c
create mode 100644 drivers/input/touchscreen/axiom_core.h
create mode 100644 drivers/input/touchscreen/axiom_i2c.c
diff --git a/Documentation/devicetree/bindings/vendor-prefixes.yaml b/Documentation/devicetree/bindings/vendor-prefixes.yaml
index 573578db9509..b0a3ed451f15 100644
--- a/Documentation/devicetree/bindings/vendor-prefixes.yaml
+++ b/Documentation/devicetree/bindings/vendor-prefixes.yaml
@@ -175,6 +175,8 @@ patternProperties:
"^awinic,.*":
description: Shanghai Awinic Technology Co., Ltd.
"^axentia,.*":
+ description: TouchNetix
+ "^axiom,.*":
description: Axentia Technologies AB
"^axis,.*":
description: Axis Communications AB
diff --git a/MAINTAINERS b/MAINTAINERS
index 389fe9e38884..43add48257d8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -3373,6 +3373,13 @@ W: https://ez.analog.com/linux-software-drivers
F: Documentation/devicetree/bindings/hwmon/adi,axi-fan-control.yaml
F: drivers/hwmon/axi-fan-control.c
+AXIOM I2C TOUCHSCREEN DRIVER
+M: Kamel Bouhara <kamel.bouhara@xxxxxxxxxxx>
+L: linux-input@xxxxxxxxxxxxxxx
+S: Maintained
+F: drivers/input/touchscreen/axiom_core.c
+F: drivers/input/touchscreen/axiom_i2.c
+
AXXIA I2C CONTROLLER
M: Krzysztof Adamski <krzysztof.adamski@xxxxxxxxx>
L: linux-i2c@xxxxxxxxxxxxxxx
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index e3e2324547b9..08a770a0c5e5 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -150,6 +150,17 @@ config TOUCHSCREEN_AUO_PIXCIR
To compile this driver as a module, choose M here: the
module will be called auo-pixcir-ts.
+config TOUCHSCREEN_AXIOM_I2C
+ tristate "AXIOM based multi-touch panel controllers"
+ 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_i2c.
+
config TOUCHSCREEN_BU21013
tristate "BU21013 based touch panel controllers"
depends on I2C
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 62bd24f3ac8e..59a3234ddb09 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_TOUCHSCREEN_ADS7846) += ads7846.o
obj-$(CONFIG_TOUCHSCREEN_AR1021_I2C) += ar1021_i2c.o
obj-$(CONFIG_TOUCHSCREEN_ATMEL_MXT) += atmel_mxt_ts.o
obj-$(CONFIG_TOUCHSCREEN_AUO_PIXCIR) += auo-pixcir-ts.o
+obj-$(CONFIG_TOUCHSCREEN_AXIOM_I2C) += axiom_core.o axiom_i2c.o
obj-$(CONFIG_TOUCHSCREEN_BU21013) += bu21013_ts.o
obj-$(CONFIG_TOUCHSCREEN_BU21029) += bu21029_ts.o
obj-$(CONFIG_TOUCHSCREEN_CHIPONE_ICN8318) += chipone_icn8318.o
diff --git a/drivers/input/touchscreen/axiom_core.c b/drivers/input/touchscreen/axiom_core.c
new file mode 100644
index 000000000000..d381afd7fb84
--- /dev/null
+++ b/drivers/input/touchscreen/axiom_core.c
@@ -0,0 +1,382 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TouchNetix aXiom Touchscreen Driver
+ *
+ * Copyright (C) 2020-2023 TouchNetix Ltd.
+ *
+ * Author(s): Mark Satterthwaite <mark.satterthwaite@xxxxxxxxxxxxxx>
+ * Pedro Torruella <pedro.torruella@xxxxxxxxxxxxxx>
+ * Bart Prescott <bartp@xxxxxxxxxxxxxx>
+ * Hannah Rossiter <hannah.rossiter@xxxxxxxxxxxxxx>
+ *
+ */
+
+#include <linux/crc16.h>
+#include <linux/device.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+
+#include "axiom_core.h"
+
+/**
+ * Decodes and populates the local u31 structure.
+ * Given a buffer of data read from page 0 of u31 in an aXiom device.
+ */
+void axiom_get_dev_info(struct axiom_data *ts, char *info)
+{
+ struct axiom_devinfo *devinfo = &ts->devinfo;
+
+ if (devinfo) {
+ devinfo->bootloader_mode = ((info[1] & 0x80) != 0) ? 1 : 0;
+ devinfo->device_id = ((info[1] & 0x7F) << 8) | info[0];
+ devinfo->fw_minor = info[2];
+ devinfo->fw_major = info[3];
+ devinfo->fw_info_extra = (info[4]) | (info[5] << 8);
+ devinfo->bootloader_fw_ver_minor = info[6];
+ devinfo->bootloader_fw_ver_major = info[7];
+ devinfo->jedec_id = (info[8]) | (info[9] << 8);
+ devinfo->num_usages = info[10];
+ devinfo->silicon_revision = info[11];
+ }
+}
+EXPORT_SYMBOL_GPL(axiom_get_dev_info);
+
+/**
+ * Decodes and populates the local Usage Table.
+ * Given a buffer of data read from page 1 onwards of u31 from an aXiom
+ * device.
+ */
+char axiom_populate_usage_table(struct axiom_data *ts, char *rx_data)
+{
+ u32 usage_id = 0;
+ char max_report_len = 0;
+ struct axiom_devinfo *device_info;
+ struct usage_entry *usage_table;
+
+ device_info = &ts->devinfo;
+ usage_table = ts->usage_table;
+
+ for (usage_id = 0; usage_id < device_info->num_usages; usage_id++) {
+ u16 offset = (usage_id * U31_BYTES_PER_USAGE);
+ char id = rx_data[offset + 0];
+ char start_page = rx_data[offset + 1];
+ char num_pages = rx_data[offset + 2];
+ char max_offset = ((rx_data[offset + 3] & 0x7F) + 1) * 2;
+
+ /* Store the entry into the usage table */
+ usage_table[usage_id].id = id;
+ usage_table[usage_id].is_report = ((num_pages == 0) ? 1 : 0);
+ usage_table[usage_id].start_page = start_page;
+ usage_table[usage_id].num_pages = num_pages;
+
+ dev_dbg(ts->pdev, "Usage %2u Info: %*ph\n", usage_id,
+ U31_BYTES_PER_USAGE, &rx_data[offset]);
+
+ /* Identify the max report length the module will receive */
+ if ((usage_table[usage_id].is_report)
+ && (max_offset > max_report_len))
+ max_report_len = max_offset;
+ }
+ ts->usage_table_populated = true;
+
+ return max_report_len;
+}
+EXPORT_SYMBOL_GPL(axiom_populate_usage_table);
+
+/**
+ * Translate usage/page/offset triplet into physical address.
+ *
+ * @usage: groups of registers
+ * @page: page to which the usage belongs to offset
+ * @offset of the usage
+ */
+u16
+usage_to_target_address(struct axiom_data *ts, char usage, char page,
+ char offset)
+{
+ struct axiom_devinfo *device_info;
+ struct usage_entry *usage_table;
+ u16 target_address;
+ u32 i;
+
+ device_info = &ts->devinfo;
+ usage_table = ts->usage_table;
+
+ /* At the moment the convention is that u31 is always at physical address 0x0 */
+ if (!ts->usage_table_populated && (usage == DEVINFO_USAGE_ID)) {
+ target_address = ((page << 8) + offset);
+ } else if (ts->usage_table_populated) {
+ for (i = 0; i < device_info->num_usages; i++) {
+ if (usage_table[i].id == usage) {
+ if (page < usage_table[i].num_pages) {
+ target_address =
+ ((usage_table[i].start_page + page) << 8) + offset;
+ } else {
+ target_address = 0xFFFF;
+ dev_err(ts->pdev,
+ "Invalid usage table! usage: %u, page: %u, offset: %u\n",
+ usage, page, offset);
+ }
+ break;
+ }
+ }
+ } else {
+ target_address = 0xFFFF;
+ dev_err(ts->pdev, "Unpopulated usage table for usage: %u\n",
+ usage);
+ }
+
+ dev_dbg(ts->pdev, "target_address is 0x%04x for usage: %u page %u\n",
+ target_address, usage, page);
+
+ return target_address;
+}
+EXPORT_SYMBOL_GPL(usage_to_target_address);
+
+void axiom_remove(struct axiom_data *ts)
+{
+ if (ts->usage_table)
+ ts->usage_table_populated = false;
+
+ if (ts->input_dev)
+ input_unregister_device(ts->input_dev);
+}
+EXPORT_SYMBOL_GPL(axiom_remove);
+
+/*
+ * Support function to axiom_process_u41_report.
+ * It 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;
+ enum axiom_target_state current_state;
+ struct u41_target *target_prev_state;
+ struct device *pdev = ts->pdev;
+ bool update = false;
+ int slot;
+
+ /* Verify the target index */
+ if (target->index >= U41_MAX_TARGETS) {
+ dev_dbg(pdev, "Invalid target index! %u\n", target->index);
+ return false;
+ }
+
+ target_prev_state = &ts->targets[target->index];
+
+ current_state =
+ ((target->present == 0) ? TARGET_STATE_NOT_PRESENT : (target->z >=
+ 0) ?
+ TARGET_STATE_TOUCHING : (target->z > PROX_LEVEL)
+ && (target->z < 0) ? TARGET_STATE_HOVER : (target->z ==
+ PROX_LEVEL) ?
+ TARGET_STATE_PROX : TARGET_STATE_NOT_PRESENT);
+ 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;
+ }
+
+ slot = target->index;
+
+ dev_dbg(pdev, "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) {
+ default:
+ case TARGET_STATE_NOT_PRESENT:
+ case TARGET_STATE_PROX:
+ {
+ if (target_prev_state->insert) {
+ update = true;
+ target_prev_state->insert = false;
+ input_mt_slot(input_dev, slot);
+
+ if (slot == 0)
+ input_report_key(input_dev, BTN_LEFT,
+ 0);
+
+ input_mt_report_slot_inactive(input_dev);
+ /* make sure the previous coordinates are all off */
+ /* screen when the finger comes back */
+ target->x = target->y = 65535;
+ target->z = PROX_LEVEL;
+ }
+ break;
+ }
+ case TARGET_STATE_HOVER:
+ case TARGET_STATE_TOUCHING:
+ {
+ target_prev_state->insert = true;
+ update = true;
+ input_mt_slot(input_dev, slot);
+ input_report_abs(input_dev, ABS_MT_TRACKING_ID, slot);
+ input_report_abs(input_dev, ABS_MT_POSITION_X,
+ target->x);
+ input_report_abs(input_dev, ABS_X, target->x);
+ input_report_abs(input_dev, ABS_MT_POSITION_Y,
+ target->y);
+ input_report_abs(input_dev, ABS_Y, target->y);
+
+ if (current_state == 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 (slot == 0)
+ input_report_key(input_dev, BTN_LEFT,
+ (current_state ==
+ TARGET_STATE_TOUCHING));
+
+ 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;
+
+ if (update)
+ input_mt_sync_frame(input_dev);
+
+ return update;
+}
+
+/**
+ * Take a raw buffer with u41 report data and decode it.
+ * Also generate input events if needed.
+ * @rx_buf: ptr to a byte array [0]: Usage number [1]: Status LSB [2]: Status MSB
+ */
+void axiom_process_u41_report(struct axiom_data *ts, char *rx_buf)
+{
+ struct axiom_target_report target;
+ struct input_dev *input_dev = ts->input_dev;
+ bool update_done = false;
+ u16 target_status;
+ u32 i;
+
+ if (rx_buf[0] != 0x41) {
+ dev_err(ts->pdev,
+ "Data in buffer does not have expected u41 format.\n");
+ return;
+ }
+
+ target_status = ((rx_buf[1]) | (rx_buf[2] << 8));
+
+ for (i = 0; i < U41_MAX_TARGETS; i++) {
+ target.index = i;
+ target.present = ((target_status & (1 << i)) != 0) ? 1 : 0;
+ target.x = (rx_buf[(i * 4) + 3]) | (rx_buf[(i * 4) + 4] << 8);
+ target.y = (rx_buf[(i * 4) + 5]) | (rx_buf[(i * 4) + 6] << 8);
+ target.z = (s8) (rx_buf[i + 43]);
+ update_done |= axiom_process_u41_report_target(ts, &target);
+ }
+
+ if (update_done)
+ input_sync(input_dev);
+}
+EXPORT_SYMBOL_GPL(axiom_process_u41_report);
+
+void axiom_process_u46_report(struct axiom_data *ts, char *rx_buf)
+{
+ struct input_dev *input_dev = ts->input_dev;
+ u16 aux_value;
+ u32 event_value;
+ u32 i = 0;
+
+ for (i = 0; i < U46_AUX_CHANNELS; i++) {
+ aux_value =
+ ((rx_buf[(i * 2) + 2] << 8) | (rx_buf[(i * 2) + 1])) &
+ U46_AUX_MASK;
+ event_value = (i << 16) | (aux_value);
+ input_event(input_dev, EV_MSC, MSC_RAW, event_value);
+ }
+
+ input_mt_sync(input_dev);
+ input_sync(input_dev);
+}
+EXPORT_SYMBOL_GPL(axiom_process_u46_report);
+
+/**
+ * Support function to axiom_process_report.
+ * It validates the crc and multiplexes the axiom reports to the appropriate
+ * report handler
+ */
+void axiom_process_report(struct axiom_data *ts, char *report_data)
+{
+ struct device *pdev = ts->pdev;
+ char usage = report_data[1];
+ u16 crc_report;
+ u16 crc_calc;
+ char len;
+
+ if ((report_data[0] & COMMS_OVERFLOW_MSK) != 0)
+ ts->report_overflow_counter++;
+
+ len = (report_data[0] & COMMS_REPORT_LEN_MSK) << 1;
+ if (len == 0) {
+ dev_err(pdev, "Zero length report discarded.\n");
+ return;
+ }
+
+ dev_dbg(pdev, "Payload Data %*ph\n", len, report_data);
+
+ /* Validate the report CRC */
+ crc_report = (report_data[len - 1] << 8) | (report_data[len - 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(pdev,
+ "CRC mismatch! Expected: %#x, Calculated CRC: %#x.\n",
+ crc_report, crc_calc);
+ return;
+ }
+
+ switch (usage) {
+ case USAGE_2DCTS_REPORT_ID:
+ axiom_process_u41_report(ts, &report_data[1]);
+ break;
+
+ case USAGE_2AUX_REPORT_ID:
+ /* This is an aux report (force) */
+ axiom_process_u46_report(ts, &report_data[1]);
+ break;
+
+ case USAGE_2HB_REPORT_ID:
+ /* This is a heartbeat report */
+ break;
+
+ default:
+ break;
+ }
+
+ ts->report_counter++;
+}
+EXPORT_SYMBOL_GPL(axiom_process_report);
+
+MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("aXiom touchscreen core logic");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("axiom");
diff --git a/drivers/input/touchscreen/axiom_core.h b/drivers/input/touchscreen/axiom_core.h
new file mode 100644
index 000000000000..f129d28671ff
--- /dev/null
+++ b/drivers/input/touchscreen/axiom_core.h
@@ -0,0 +1,140 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * TouchNetix aXiom Touchscreen Driver
+ *
+ * Copyright (C) 2020-2023 TouchNetix Ltd.
+ *
+ * Author(s): Mark Satterthwaite <mark.satterthwaite@xxxxxxxxxxxxxx>
+ * Pedro Torruella <pedro.torruella@xxxxxxxxxxxxxx>
+ * Bart Prescott <bartp@xxxxxxxxxxxxxx>
+ * Hannah Rossiter <hannah.rossiter@xxxxxxxxxxxxxx>
+ *
+ * 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.
+ *
+ */
+
+#ifndef __AXIOM_CORE_H
+#define __AXIOM_CORE_H
+
+/* Enables the raw data for up to 4 force channels to be sent to the input subsystem */
+#define U46_ENABLE_RAW_FORCE_DATA
+
+/**
+ * u31 has 2 pages for usage table entries.
+ * (2 * AX_COMMS_PAGE_SIZE) / U31_BYTES_PER_USAGE = 85
+ */
+#define U31_MAX_USAGES (85U)
+#define U41_MAX_TARGETS (10U)
+#define U46_AUX_CHANNELS (4U)
+#define U46_AUX_MASK (0xFFFU)
+#define U31_BYTES_PER_USAGE (6U)
+#define USAGE_2DCTS_REPORT_ID (0x41U)
+#define USAGE_2AUX_REPORT_ID (0x46U)
+#define USAGE_2HB_REPORT_ID (0x01U)
+#define PROX_LEVEL (-128)
+#define AX_U31_PAGE0_LENGTH (0x0C)
+#define AX_COMMS_WRITE (0x00U)
+#define AX_COMMS_READ (0x80U)
+#define AX_COMMS_BYTES_MASK (0xFFU)
+
+#define DEVINFO_USAGE_ID 0x31
+#define REPORT_USAGE_ID 0x34
+
+#define REBASELINE_CMD 0x03
+
+#define COMMS_MAX_USAGE_PAGES (3)
+#define AX_COMMS_PAGE_SIZE (256)
+
+#define COMMS_OVERFLOW_MSK (0x80)
+#define COMMS_REPORT_LEN_MSK (0x7F)
+
+#include <linux/input.h>
+
+struct axiom_devinfo {
+ char bootloader_fw_ver_major;
+ char bootloader_fw_ver_minor;
+ char bootloader_mode;
+ u16 device_id;
+ char fw_major;
+ char fw_minor;
+ u16 fw_info_extra;
+ u16 jedec_id;
+ char num_usages;
+ char silicon_revision;
+};
+
+/**
+ * Describes parameters of a specific usage, essenstially a single element of
+ * the "Usage Table"
+ */
+struct usage_entry {
+ char id;
+ char is_report;
+ char start_page;
+ char num_pages;
+};
+
+/**
+ * Holds state of a "Target", A.K.A. as a "touch", but called a target as it
+ * can be a detected "target" prior to touch, eg, hovering.
+ */
+enum axiom_target_state {
+ TARGET_STATE_NOT_PRESENT = 0,
+ TARGET_STATE_PROX = 1,
+ TARGET_STATE_HOVER = 2,
+ TARGET_STATE_TOUCHING = 3,
+ TARGET_STATE_MIN = TARGET_STATE_NOT_PRESENT,
+ TARGET_STATE_MAX = TARGET_STATE_TOUCHING,
+};
+
+struct 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 {
+ u16 target_address;
+ u16 length:15;
+ u16 read:1;
+ char write_data[];
+};
+
+struct axiom_data {
+ struct axiom_devinfo devinfo;
+ struct device *pdev;
+ struct gpio_desc *reset_gpio;
+ struct gpio_desc *irq_gpio;
+ struct i2c_client *client;
+ struct input_dev *input_dev;
+ char max_report_len;
+ u32 report_overflow_counter;
+ u32 report_counter;
+ char rx_buf[COMMS_MAX_USAGE_PAGES * AX_COMMS_PAGE_SIZE];
+ struct u41_target targets[U41_MAX_TARGETS];
+ struct usage_entry usage_table[U31_MAX_USAGES];
+ bool usage_table_populated;
+};
+
+extern u16 usage_to_target_address(struct axiom_data *ts, char usage,
+ char page, char offset);
+extern void axiom_process_report(struct axiom_data *ts, char *report_data);
+extern char axiom_populate_usage_table(struct axiom_data *ts, char *rx_data);
+extern void axiom_remove(struct axiom_data *ts);
+extern void axiom_get_dev_info(struct axiom_data *ts, char *info);
+
+#endif /* __AXIOM_CORE_H */
diff --git a/drivers/input/touchscreen/axiom_i2c.c b/drivers/input/touchscreen/axiom_i2c.c
new file mode 100644
index 000000000000..ddb898ad3744
--- /dev/null
+++ b/drivers/input/touchscreen/axiom_i2c.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * TouchNetix aXiom Touchscreen Driver
+ *
+ * Copyright (C) 2020-2023 TouchNetix Ltd.
+ *
+ * Author(s): Bart Prescott <bartp@xxxxxxxxxxxxxx>
+ * Pedro Torruella <pedro.torruella@xxxxxxxxxxxxxx>
+ * Mark Satterthwaite <mark.satterthwaite@xxxxxxxxxxxxxx>
+ * Hannah Rossiter <hannah.rossiter@xxxxxxxxxxxxxx>
+ *
+ */
+
+#include "axiom_core.h"
+
+#include <linux/delay.h>
+#include <linux/gpio/consumer.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/kobject.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/pm.h>
+#include <linux/string.h>
+
+/**
+ * aXiom devices are typically configured to report
+ * touches at a rate of 100Hz (10ms). For systems
+ * that require polling for reports, 100ms seems like
+ * an acceptable polling rate.
+ * 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 100
+
+static int
+axiom_i2c_read(struct i2c_client *client, u8 usage, u8 page, u8 *buf, u16 len)
+{
+ struct axiom_cmd_header cmd_header;
+ struct axiom_data *ts = i2c_get_clientdata(client);
+ struct i2c_msg msg[2];
+ int ret;
+
+ /* Build the header */
+ cmd_header.target_address = usage_to_target_address(ts, usage, page, 0);
+ cmd_header.length = len;
+ cmd_header.read = 1;
+
+ msg[0].addr = client->addr;
+ msg[0].flags = 0;
+ msg[0].len = sizeof(cmd_header);
+ msg[0].buf = (u8 *)&cmd_header;
+
+ msg[1].addr = client->addr;
+ msg[1].flags = I2C_M_RD;
+ msg[1].len = len;
+ msg[1].buf = (char *)buf;
+
+ ret = i2c_transfer(client->adapter, msg, 2);
+ if (ret != ARRAY_SIZE(msg)) {
+ dev_err(&client->dev,
+ "Failed reading usage %#x page %#x, error=%d\n", usage,
+ page, ret);
+ return -EIO;
+ }
+
+ return 0;
+}
+
+static int
+axiom_i2c_write(struct i2c_client *client, u8 usage, u8 page, u8 *buf, u16 len)
+{
+ struct axiom_cmd_header cmd_header;
+ struct axiom_data *ts = i2c_get_clientdata(client);
+ struct i2c_msg msg[2];
+ int ret;
+
+ cmd_header.target_address = usage_to_target_address(ts, usage, page, 0);
+ cmd_header.length = len;
+ cmd_header.read = 0;
+
+ msg[0].addr = client->addr;
+ msg[0].flags = 0;
+ msg[0].len = sizeof(cmd_header);
+ msg[0].buf = (u8 *)&cmd_header;
+
+ msg[1].addr = client->addr;
+ msg[1].flags = 0;
+ msg[1].len = len;
+ msg[1].buf = (char *)buf;
+
+ ret = i2c_transfer(client->adapter, msg, 2);
+ if (ret != 2) {
+ dev_err(&client->dev,
+ "Failed to write usage %#x page %#x, error=%d\n", usage,
+ page, ret);
+ return ret;
+ }
+
+ return 0;
+}
+
+static void axiom_i2c_poll(struct input_dev *input_dev)
+{
+ struct axiom_data *ts = input_get_drvdata(input_dev);
+ char *rx_data = ts->rx_buf;
+
+ axiom_i2c_read(ts->client, REPORT_USAGE_ID, 0, rx_data,
+ ts->max_report_len);
+ axiom_process_report(ts, rx_data);
+}
+
+/**
+ * Retrieve, store and print the axiom device information
+ */
+int axiom_discover(struct axiom_data *ts)
+{
+ char *rx_data = &ts->rx_buf[0];
+ struct device *pdev = ts->pdev;
+ int ret;
+
+ /* First the first page of u31 to get the device information and */
+ /* the number of usages */
+ ret =
+ axiom_i2c_read(ts->client, DEVINFO_USAGE_ID, 0, rx_data,
+ AX_U31_PAGE0_LENGTH);
+ if (ret)
+ return ret;
+
+ axiom_get_dev_info(ts, rx_data);
+
+ dev_dbg(pdev, "Data Decode:\n");
+ dev_dbg(pdev, " Bootloader Mode: %u\n", ts->devinfo.bootloader_mode);
+ dev_dbg(pdev, " Device ID : %04x\n", ts->devinfo.device_id);
+ dev_dbg(pdev, " Firmware Rev : %02x.%02x\n", ts->devinfo.fw_major,
+ ts->devinfo.fw_minor);
+ dev_dbg(pdev, " Bootloader Rev : %02x.%02x\n",
+ ts->devinfo.bootloader_fw_ver_major,
+ ts->devinfo.bootloader_fw_ver_minor);
+ dev_dbg(pdev, " FW Extra Info : %04x\n", ts->devinfo.fw_info_extra);
+ dev_dbg(pdev, " Silicon : %02x\n", ts->devinfo.jedec_id);
+ dev_dbg(pdev, " Num Usages : %04x\n", ts->devinfo.num_usages);
+
+ /* Read the second page of u31 to get the usage table */
+ ret = axiom_i2c_read(ts->client, DEVINFO_USAGE_ID, 1, rx_data,
+ (U31_BYTES_PER_USAGE * ts->devinfo.num_usages));
+ if (ret)
+ return ret;
+
+ ts->max_report_len = axiom_populate_usage_table(ts, rx_data);
+ dev_dbg(pdev, "Max Report Length: %u\n", ts->max_report_len);
+
+ return 0;
+}
+EXPORT_SYMBOL_GPL(axiom_discover);
+
+/**
+ * Rebaseline the touchscreen, effectively zero-ing it
+ */
+void axiom_rebaseline(struct axiom_data *ts)
+{
+ struct device *pdev = ts->pdev;
+ char buffer[8] = { 0 };
+ int ret;
+
+ memset(buffer, 0, sizeof(buffer));
+
+ buffer[0] = REBASELINE_CMD;
+
+ ret = axiom_i2c_write(ts->client, 0x02, 0, buffer, sizeof(buffer));
+ if (ret)
+ dev_err(pdev, "Rebaseline failed\n");
+
+ dev_info(pdev, "Capture Baseline Requested\n");
+}
+EXPORT_SYMBOL_GPL(axiom_rebaseline);
+
+static irqreturn_t axiom_irq(int irq, void *handle)
+{
+ struct axiom_data *ts = handle;
+ u8 *rx_data = &ts->rx_buf[0];
+
+ axiom_i2c_read(ts->client, REPORT_USAGE_ID, 0, rx_data, ts->max_report_len);
+ axiom_process_report(ts, rx_data);
+
+ return IRQ_HANDLED;
+}
+
+static int axiom_i2c_probe(struct i2c_client *client)
+{
+ struct axiom_data *ts;
+ struct device *pdev = &client->dev;
+ struct input_dev *input_dev;
+ int error;
+ int target;
+
+ ts = devm_kzalloc(pdev, sizeof(*ts), GFP_KERNEL);
+ if (!ts)
+ return -ENOMEM;
+
+ ts->irq_gpio = devm_gpiod_get_optional(pdev, "irq", GPIOD_IN);
+ if (IS_ERR(ts->irq_gpio)) {
+ error = PTR_ERR(ts->irq_gpio);
+ dev_err(pdev, "failed to request irq GPIO: %d", error);
+ return error;
+ }
+
+ ts->reset_gpio = devm_gpiod_get_optional(pdev, "reset", GPIOD_OUT_HIGH);
+ if (IS_ERR(ts->reset_gpio)) {
+ error = PTR_ERR(ts->reset_gpio);
+ dev_err(pdev, "failed to request reset GPIO: %d", error);
+ return error;
+ }
+
+ if (ts->irq_gpio) {
+ error =
+ devm_request_threaded_irq(pdev, client->irq, NULL,
+ axiom_irq,
+ IRQF_TRIGGER_LOW | IRQF_ONESHOT,
+ "axiom_irq", ts);
+ if (error != 0) {
+ dev_err(pdev, "Failed to request IRQ %u (error: %d)\n",
+ client->irq, error);
+ return error;
+ }
+ }
+
+ ts->client = client;
+ ts->pdev = pdev;
+ ts->usage_table_populated = false;
+
+ i2c_set_clientdata(client, ts);
+
+ axiom_discover(ts);
+ axiom_rebaseline(ts);
+
+ input_dev = devm_input_allocate_device(ts->pdev);
+ if (!input_dev) {
+ dev_err(pdev, "Failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ input_dev->name = "TouchNetix aXiom Touchscreen";
+ input_dev->phys = "input/axiom_ts";
+
+ /* Single Touch */
+ input_set_abs_params(input_dev, ABS_X, 0, 65535, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, 65535, 0, 0);
+
+ /* Multi Touch */
+ /* Min, Max, Fuzz (expected noise in px, try 4?) and Flat */
+ input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0, 65535, 0, 0);
+ /* Min, Max, Fuzz (expected noise in px, try 4?) and Flat */
+ 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);
+
+ /* Registers the axiom device as a touch screen instead of as a mouse pointer */
+ input_mt_init_slots(input_dev, U41_MAX_TARGETS, INPUT_MT_DIRECT);
+
+ input_set_capability(input_dev, EV_KEY, BTN_LEFT);
+
+ /* 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);
+
+ if (!ts->irq_gpio) {
+ error = input_setup_polling(input_dev, axiom_i2c_poll);
+ if (error) {
+ dev_err(ts->pdev, "Unable to set up polling: %d\n",
+ error);
+ return error;
+ }
+ input_set_poll_interval(input_dev, POLL_INTERVAL_DEFAULT_MS);
+ }
+
+ error = input_register_device(input_dev);
+ if (error != 0) {
+ dev_err(ts->pdev,
+ "Could not register with Input Sub-system., error=%d\n",
+ error);
+ return error;
+ }
+
+ ts->input_dev = input_dev;
+ input_set_drvdata(ts->input_dev, ts);
+
+ dev_info(pdev, "AXIOM: I2C driver registered with Input Sub-System.\n");
+
+ /* Delay just a smidge before enabling the IRQ */
+ udelay(10);
+
+ /* Ensure that all reports are initialised to not be present. */
+ for (target = 0; target < U41_MAX_TARGETS; target++)
+ ts->targets[target].state = TARGET_STATE_NOT_PRESENT;
+
+ return 0;
+}
+
+static void axiom_i2c_remove(struct i2c_client *client)
+{
+ struct axiom_data *ts = i2c_get_clientdata(client);
+
+ axiom_remove(ts);
+}
+
+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_dt_ids[] = {
+ {
+ .compatible = "axiom,ax54a",
+ .data = "axiom",
+ },
+ {}
+};
+
+MODULE_DEVICE_TABLE(of, axiom_i2c_dt_ids);
+
+static struct i2c_driver axiom_i2c_driver = {
+ .driver = {
+ .name = "axiom_i2c",
+ .of_match_table = of_match_ptr(axiom_i2c_dt_ids),
+ },
+ .id_table = axiom_i2c_id_table,
+ .probe = axiom_i2c_probe,
+ .remove = axiom_i2c_remove,
+};
+
+module_i2c_driver(axiom_i2c_driver);
+
+MODULE_AUTHOR("Kamel Bouhara <kamel.bouhara@xxxxxxxxxxx>");
+MODULE_DESCRIPTION("aXiom touchscreen I2C bus driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("axiom");
--
2.25.1
