From patchwork Thu Oct 12 07:40:34 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kamel BOUHARA X-Patchwork-Id: 733504 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7AAF5CDB46E for ; Thu, 12 Oct 2023 07:41:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1378101AbjJLHlC (ORCPT ); Thu, 12 Oct 2023 03:41:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59308 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347181AbjJLHkx (ORCPT ); Thu, 12 Oct 2023 03:40:53 -0400 Received: from relay2-d.mail.gandi.net (relay2-d.mail.gandi.net [217.70.183.194]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D3FEDC0; Thu, 12 Oct 2023 00:40:49 -0700 (PDT) Received: by mail.gandi.net (Postfix) with ESMTPSA id 31E5B40006; Thu, 12 Oct 2023 07:40:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1697096448; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lJs8XI2L51rAADiE3IuVleFMTlDlM+265LS9AyL0O0g=; b=XSLXN0u5Cgg883JFTNDm+q5Afb63N6YqG+NUJwCFpsLg+vYvngNH4pHU62HcV/0+JXPtt8 v+n4dosh4vLWlxth7IKKWa/JTVv+iq/oGKMKKDVINhB7bDMxrCGwMBUYvDIa3hys+ZgU9d 0nZMytaqrmDKjlnXXNcioU8LJpUPUP+CVfFZcqyxG8/ORMcePSO4F2Z+YZ1CMBG56C+Qni 6Sjv8R2l8ikB573BW/ue4pB0Do3d0yZSf/PUP+5/65URb356F62GxcQLlwkQiKJj4OXThF EkEMyv10yrs4GnZfwS5DS2GutM5yV5ZrLEIxAfPuV0aeXTQA5JMWqUmw7jwhrQ== From: Kamel Bouhara To: Dmitry Torokhov , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Henrik Rydberg Cc: linux-input@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, Marco Felsch , mark.satterthwaite@touchnetix.com, bartp@baasheep.co.uk, hannah.rossiter@touchnetix.com, Thomas Petazzoni , Gregory Clement , bsp-development.geo@leica-geosystems.com, Kamel Bouhara Subject: [PATCH v3 3/3] Input: Add TouchNetix axiom i2c touchscreen driver Date: Thu, 12 Oct 2023 09:40:34 +0200 Message-Id: <20231012074034.1090436-4-kamel.bouhara@bootlin.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20231012074034.1090436-1-kamel.bouhara@bootlin.com> References: <20231012074034.1090436-1-kamel.bouhara@bootlin.com> MIME-Version: 1.0 X-GND-Sasl: kamel.bouhara@bootlin.com Precedence: bulk List-ID: X-Mailing-List: linux-input@vger.kernel.org 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 --- MAINTAINERS | 1 + drivers/input/touchscreen/Kconfig | 13 + drivers/input/touchscreen/Makefile | 1 + .../input/touchscreen/touchnetix_axiom_i2c.c | 740 ++++++++++++++++++ 4 files changed, 755 insertions(+) create mode 100644 drivers/input/touchscreen/touchnetix_axiom_i2c.c diff --git a/MAINTAINERS b/MAINTAINERS index 12ae8bc6b8cf..2d1e0b025e89 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -21415,6 +21415,7 @@ M: Kamel Bouhara L: linux-input@vger.kernel.org S: Maintained F: Documentation/devicetree/bindings/input/touchscreen/touchnetix,axiom-ax54a.yaml +F: drivers/input/touchscreen/touchnetix_axiom_i2c.c THUNDERBOLT DMA TRAFFIC TEST DRIVER M: Isaac Hazan diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig index e3e2324547b9..58665ccbe077 100644 --- a/drivers/input/touchscreen/Kconfig +++ b/drivers/input/touchscreen/Kconfig @@ -803,6 +803,19 @@ config TOUCHSCREEN_MIGOR To compile this driver as a module, choose M here: the module will be called migor_ts. +config TOUCHSCREEN_TOUCHNETIX_AXIOM_I2C + tristate "TouchNetix AXIOM based touchscreen controllers" + depends on I2C + depends on GPIOLIB || COMPILE_TEST + 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_TOUCHRIGHT tristate "Touchright serial touchscreen" select SERIO diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile index 62bd24f3ac8e..23b6fb8864b0 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-$(CONFIG_TOUCHSCREEN_TOUCHNETIX_AXIOM_I2C) += touchnetix_axiom_i2c.o obj-$(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_i2c.c b/drivers/input/touchscreen/touchnetix_axiom_i2c.c new file mode 100644 index 000000000000..fb6239a87341 --- /dev/null +++ b/drivers/input/touchscreen/touchnetix_axiom_i2c.c @@ -0,0 +1,740 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * TouchNetix aXiom Touchscreen Driver + * + * Copyright (C) 2020-2023 TouchNetix Ltd. + * + * Author(s): Bart Prescott + * Pedro Torruella + * Mark Satterthwaite + * Hannah Rossiter + * Kamel Bouhara + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Runtime TCP mode: device is executing normal code and is + * accessible via the Touch Controller Mode + */ +#define BOOT_TCP 0 +/* + * Bootloader BLP mode: device is executing bootloader and is + * accessible via the Boot Loader Protocol. + */ +#define BOOT_BLP 1 +#define AXIOM_PROX_LEVEL -128 +/* + * Register group u31 has 2 pages for usage table entries. + * (2 * AXIOM_COMMS_PAGE_SIZE) / AXIOM_U31_BYTES_PER_USAGE = 85 + */ +#define AXIOM_U31_MAX_USAGES 85 +#define AXIOM_U31_BYTES_PER_USAGE 6 +#define AXIOM_U31_PAGE0_LENGTH 0x0C +#define AXIOM_U31_BOOTMODE_MASK BIT(7) +#define AXIOM_U31_FW_INFO_VARIANT_MASK GENMASK(6, 0) +#define AXIOM_U31_FW_INFO_STATUS_MASK BIT(7) + +#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_OVERFLOW_MASK BIT(7) +#define AXIOM_COMMS_REPORT_LEN_MASK GENMASK(7, 0) + +#define AXIOM_REBASELINE_CMD 0x03 + +#define AXIOM_REPORT_USAGE_ID 0x34 +#define AXIOM_DEVINFO_USAGE_ID 0x31 +#define AXIOM_USAGE_2HB_REPORT_ID 0x01 +#define AXIOM_REBASELINE_USAGE_ID 0x02 +#define AXIOM_USAGE_2AUX_REPORT_ID 0x46 +#define AXIOM_USAGE_2DCTS_REPORT_ID 0x41 + +#define AXIOM_PAGE_MASK GENMASK(15, 8) +#define AXIOM_PAGE_OFFSET_MASK GENMASK(7, 0) + +struct axiom_devinfo { + char bootloader_fw_major; + char bootloader_fw_minor; + char bootmode; + u16 device_id; + char fw_major; + char fw_minor; + char fw_info_extra; + char tcp_revision; + 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 touch or target when detected prior a touch (eg. + * hover or proximity events). + */ +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; +} __packed; + +struct axiom_data { + struct axiom_devinfo devinfo; + struct device *dev; + struct gpio_desc *reset_gpio; + struct gpio_desc *irq_gpio; + struct i2c_client *client; + struct input_dev *input_dev; + u32 max_report_len; + u32 report_overflow_counter; + u32 report_counter; + char rx_buf[AXIOM_COMMS_MAX_USAGE_PAGES * AXIOM_COMMS_PAGE_SIZE]; + struct u41_target targets[AXIOM_U41_MAX_TARGETS]; + struct usage_entry usage_table[AXIOM_U31_MAX_USAGES]; + bool usage_table_populated; +}; + +/* + * 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 + +/* Translate usage/page/offset triplet into physical address. */ +static 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; + 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) { + if (usage == AXIOM_DEVINFO_USAGE_ID) + return ((page << 8) + offset); + else + return 0xffff; + } + + for (i = 0; i < device_info->num_usages; i++) { + if (usage_table[i].id != usage) + continue; + + if (page >= usage_table[i].num_pages) { + dev_err(ts->dev, "Invalid usage table! usage: %u, page: %u, offset: %u\n", + usage, page, offset); + return 0xffff; + } + } + + return ((usage_table[i].start_page + page) << 8) + offset; +} + +static int +axiom_i2c_read(struct i2c_client *client, u8 usage, u8 page, u8 *buf, u16 len) +{ + struct axiom_data *ts = i2c_get_clientdata(client); + struct axiom_cmd_header cmd_header; + struct i2c_msg msg[2]; + int ret; + + cmd_header.target_address = cpu_to_le16(usage_to_target_address(ts, usage, page, 0)); + cmd_header.length = cpu_to_le16(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_data *ts = i2c_get_clientdata(client); + struct axiom_cmd_header cmd_header; + struct i2c_msg msg[2]; + int ret; + + cmd_header.target_address = cpu_to_le16(usage_to_target_address(ts, usage, page, 0)); + cmd_header.length = cpu_to_le16(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 < 0) { + dev_err(&client->dev, + "Failed to write usage %#x page %#x, error=%d\n", usage, + page, ret); + return ret; + } + + return 0; +} + +/* + * Decodes and populates the local Usage Table. + * Given a buffer of data read from page 1 onwards of u31 from an aXiom + * device. + */ +static u32 axiom_populate_usage_table(struct axiom_data *ts, char *rx_data) +{ + u32 usage_id = 0; + u32 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 * AXIOM_U31_BYTES_PER_USAGE); + char id = rx_data[offset + 0]; + char start_page = rx_data[offset + 1]; + char num_pages = rx_data[offset + 2]; + u32 max_offset = ((rx_data[offset + 3] & AXIOM_PAGE_OFFSET_MASK) + 1) * 2; + + if (!num_pages) + usage_table[usage_id].is_report = true; + + /* Store the entry into the usage table */ + usage_table[usage_id].id = id; + usage_table[usage_id].start_page = start_page; + usage_table[usage_id].num_pages = num_pages; + + dev_dbg(ts->dev, "Usage %2u Info: %*ph\n", usage_id, + AXIOM_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; +} + +/* Retrieve, store and print the axiom device information */ +static int axiom_discover(struct axiom_data *ts) +{ + struct axiom_devinfo *devinfo = &ts->devinfo; + struct device *dev = ts->dev; + char *rx_data = ts->rx_buf; + int ret; + + /* + * Fetch the first page of usage u31 to get the + * device information and the number of usages + */ + ret = axiom_i2c_read(ts->client, AXIOM_DEVINFO_USAGE_ID, 0, rx_data, + AXIOM_U31_PAGE0_LENGTH); + if (ret) + return ret; + + devinfo->bootmode = (rx_data[0] & AXIOM_U31_BOOTMODE_MASK); + devinfo->device_id = ((rx_data[1] & AXIOM_PAGE_OFFSET_MASK) << 8) | rx_data[0]; + devinfo->fw_minor = rx_data[2]; + devinfo->fw_major = rx_data[3]; + devinfo->fw_info_extra = rx_data[4]; + devinfo->bootloader_fw_minor = rx_data[6]; + devinfo->bootloader_fw_major = rx_data[7]; + devinfo->jedec_id = (rx_data[8]) | (rx_data[9] << 8); + devinfo->num_usages = rx_data[10]; + devinfo->silicon_revision = rx_data[11]; + + dev_dbg(dev, " Boot Mode: %s\n", ts->devinfo.bootmode ? "BLP" : "TCP"); + dev_dbg(dev, " Device ID : %04x\n", ts->devinfo.device_id); + dev_dbg(dev, " Firmware Rev : %02x.%02x\n", ts->devinfo.fw_major, + ts->devinfo.fw_minor); + dev_dbg(dev, " Bootloader Rev : %02x.%02x\n", + ts->devinfo.bootloader_fw_major, + ts->devinfo.bootloader_fw_minor); + dev_dbg(dev, " FW Extra Info : %04x\n", ts->devinfo.fw_info_extra); + dev_dbg(dev, " Silicon : %02x\n", ts->devinfo.jedec_id); + dev_dbg(dev, " Num Usages : %04x\n", ts->devinfo.num_usages); + + /* Read the second page of usage u31 to get the usage table */ + ret = axiom_i2c_read(ts->client, AXIOM_DEVINFO_USAGE_ID, 1, rx_data, + (AXIOM_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(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; + enum axiom_target_state current_state; + struct u41_target *target_prev_state; + struct device *dev = ts->dev; + bool update = false; + int slot; + + /* Verify the target index */ + if (target->index >= AXIOM_U41_MAX_TARGETS) { + dev_dbg(dev, "Invalid target index! %u\n", target->index); + return false; + } + + target_prev_state = &ts->targets[target->index]; + + current_state = TARGET_STATE_NOT_PRESENT; + + if (target->present) { + if (target->z >= 0) + current_state = TARGET_STATE_TOUCHING; + else if (target->z > AXIOM_PROX_LEVEL && target->z < 0) + current_state = TARGET_STATE_HOVER; + else if (target->z AXIOM_PROX_LEVEL) + current_state = 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; + } + + slot = target->index; + + dev_dbg(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 TARGET_STATE_NOT_PRESENT: + case TARGET_STATE_PROX: + if (target_prev_state->insert) + break; + update = true; + target_prev_state->insert = false; + input_mt_slot(input_dev, slot); + + if (!slot) + 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 = 65535; + target->y = 65535; + target->z = AXIOM_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) + 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 + */ +static void axiom_process_u41_report(struct axiom_data *ts, char *rx_buf) +{ + struct input_dev *input_dev = ts->input_dev; + struct axiom_target_report target; + bool update_done = false; + u16 target_status; + u32 i; + + target_status = ((rx_buf[1]) | (rx_buf[2] << 8)); + + for (i = 0; i < AXIOM_U41_MAX_TARGETS; i++) { + char target_step = rx_buf[(i * 4)]; + + target.index = i; + target.present = ((target_status & (1 << i)) != 0) ? 1 : 0; + target.x = ((target_step + 3) | ((target_step + 4) << 8)); + target.y = ((target_step + 5) | ((target_step + 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); +} + +static void axiom_process_u46_report(struct axiom_data *ts, char *rx_buf) +{ + struct input_dev *input_dev = ts->input_dev; + u32 event_value; + u16 aux_value; + u32 i = 0; + + for (i = 0; i < AXIOM_U46_AUX_CHANNELS; i++) { + char target_step = rx_buf[(i * 2)]; + + aux_value = (((target_step + 2) << 8) | (target_step + 1)) & AXIOM_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); +} + +/* + * Validates the crc and demultiplexes the axiom reports to the appropriate + * report handler + */ +static void axiom_handle_events(struct axiom_data *ts) +{ + char *report_data = ts->rx_buf; + struct device *dev = ts->dev; + char usage = report_data[1]; + u16 crc_report; + u16 crc_calc; + char len; + + axiom_i2c_read(ts->client, AXIOM_REPORT_USAGE_ID, 0, report_data, ts->max_report_len); + + if ((report_data[0] & AXIOM_COMMS_OVERFLOW_MASK) != 0) + ts->report_overflow_counter++; + + len = (report_data[0] & AXIOM_COMMS_REPORT_LEN_MASK) * 2; + if (!len) { + dev_err(dev, "Zero length report discarded.\n"); + return; + } + + dev_dbg(dev, "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(dev, + "CRC mismatch! Expected: %#x, Calculated CRC: %#x.\n", + crc_report, crc_calc); + return; + } + + switch (usage) { + case AXIOM_USAGE_2DCTS_REPORT_ID: + axiom_process_u41_report(ts, &report_data[1]); + break; + + case AXIOM_USAGE_2AUX_REPORT_ID: + /* This is an aux report (force) */ + axiom_process_u46_report(ts, &report_data[1]); + break; + + case AXIOM_USAGE_2HB_REPORT_ID: + /* This is a heartbeat report */ + break; + } + + ts->report_counter++; +} + +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(100); +} + +/* Rebaseline the touchscreen, effectively zero-ing it */ +static int axiom_rebaseline(struct axiom_data *ts) +{ + char buffer[8] = {}; + + buffer[0] = AXIOM_REBASELINE_CMD; + + return axiom_i2c_write(ts->client, AXIOM_REPORT_USAGE_ID, 0, buffer, sizeof(buffer)); +} + +static int axiom_i2c_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + struct input_dev *input_dev; + struct axiom_data *ts; + int ret; + int target; + + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + ts->client = client; + i2c_set_clientdata(client, ts); + ts->dev = dev; + + ts->irq_gpio = devm_gpiod_get_optional(dev, "irq", GPIOD_IN); + if (IS_ERR(ts->irq_gpio)) + return dev_err_probe(dev, PTR_ERR(ts->irq_gpio), "failed to get irq GPIO"); + + 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"); + + axiom_reset(ts->reset_gpio); + + if (ts->irq_gpio) { + ret = devm_request_threaded_irq(dev, client->irq, NULL, + axiom_irq, 0, dev_name(dev), ts); + if (ret < 0) + return dev_err_probe(dev, ret, "Failed to request threaded IRQ\n"); + } + + ret = axiom_discover(ts); + if (ret) + return dev_err_probe(dev, ret, "Failed touchscreen discover\n"); + + ret = axiom_rebaseline(ts); + if (ret) + return dev_err_probe(dev, ret, "Failed touchscreen re-baselining\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"; + + /* 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 touchscreen instead of as a mouse pointer */ + input_mt_init_slots(input_dev, AXIOM_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) { + ret = input_setup_polling(input_dev, axiom_i2c_poll); + if (ret) + return dev_err_probe(ts->dev, ret, "Unable to set up polling mode\n"); + input_set_poll_interval(input_dev, POLL_INTERVAL_DEFAULT_MS); + } + + 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 = TARGET_STATE_NOT_PRESENT; + + ret = input_register_device(input_dev); + + if (ret) + return dev_err_probe(ts->dev, ret, + "Could not register with Input Sub-system.\n"); + + return 0; +} + +static void axiom_i2c_remove(struct i2c_client *client) +{ + struct axiom_data *ts = i2c_get_clientdata(client); + + input_unregister_device(ts->input_dev); +} + +static const struct i2c_device_id axiom_i2c_id_table[] = { + { "axiom-ax54a" }, + {}, +}; + +MODULE_DEVICE_TABLE(i2c, axiom_i2c_id_table); + +static const struct of_device_id axiom_i2c_of_match[] = { + { .compatible = "touchnetix,axiom-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, + .remove = axiom_i2c_remove, +}; + +module_i2c_driver(axiom_i2c_driver); + +MODULE_AUTHOR("Bart Prescott "); +MODULE_AUTHOR("Pedro Torruella "); +MODULE_AUTHOR("Mark Satterthwaite "); +MODULE_AUTHOR("Hannah Rossiter "); +MODULE_AUTHOR("Kamel Bouhara "); +MODULE_DESCRIPTION("TouchNetix aXiom touchscreen I2C bus driver"); +MODULE_LICENSE("GPL");