// SPDX-License-Identifier: GPL-2.0-or-later /* * Copyright (C) 2016, Jelle van der Waa <jelle@vdwaa.nl> */ #include <linux/delay.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/module.h> #include <linux/regulator/consumer.h> #include <asm/unaligned.h> #define ZET6223_MAX_FINGERS 16 #define ZET6223_MAX_PKT_SIZE (3 + 4 * ZET6223_MAX_FINGERS) #define ZET6223_CMD_INFO 0xB2 #define ZET6223_CMD_INFO_LENGTH 17 #define ZET6223_VALID_PACKET 0x3c #define ZET6223_POWER_ON_DELAY_MSEC 30 struct zet6223_ts { struct i2c_client *client; struct input_dev *input; struct regulator *vcc; struct regulator *vio; struct touchscreen_properties prop; struct regulator_bulk_data supplies[2]; u16 max_x; u16 max_y; u8 fingernum; }; static int zet6223_start(struct input_dev *dev) { struct zet6223_ts *ts = input_get_drvdata(dev); enable_irq(ts->client->irq); return 0; } static void zet6223_stop(struct input_dev *dev) { struct zet6223_ts *ts = input_get_drvdata(dev); disable_irq(ts->client->irq); } static irqreturn_t zet6223_irq(int irq, void *dev_id) { struct zet6223_ts *ts = dev_id; u16 finger_bits; /* * First 3 bytes are an identifier, two bytes of finger data. * X, Y data per finger is 4 bytes. */ u8 bufsize = 3 + 4 * ts->fingernum; u8 buf[ZET6223_MAX_PKT_SIZE]; int i; int ret; int error; ret = i2c_master_recv(ts->client, buf, bufsize); if (ret != bufsize) { error = ret < 0 ? ret : -EIO; dev_err_ratelimited(&ts->client->dev, "Error reading input data: %d\n", error); return IRQ_HANDLED; } if (buf[0] != ZET6223_VALID_PACKET) return IRQ_HANDLED; finger_bits = get_unaligned_be16(buf + 1); for (i = 0; i < ts->fingernum; i++) { if (!(finger_bits & BIT(15 - i))) continue; input_mt_slot(ts->input, i); input_mt_report_slot_state(ts->input, MT_TOOL_FINGER, true); input_event(ts->input, EV_ABS, ABS_MT_POSITION_X, ((buf[i + 3] >> 4) << 8) + buf[i + 4]); input_event(ts->input, EV_ABS, ABS_MT_POSITION_Y, ((buf[i + 3] & 0xF) << 8) + buf[i + 5]); } input_mt_sync_frame(ts->input); input_sync(ts->input); return IRQ_HANDLED; } static void zet6223_power_off(void *_ts) { struct zet6223_ts *ts = _ts; regulator_bulk_disable(ARRAY_SIZE(ts->supplies), ts->supplies); } static int zet6223_power_on(struct zet6223_ts *ts) { struct device *dev = &ts->client->dev; int error; ts->supplies[0].supply = "vio"; ts->supplies[1].supply = "vcc"; error = devm_regulator_bulk_get(dev, ARRAY_SIZE(ts->supplies), ts->supplies); if (error) return error; error = regulator_bulk_enable(ARRAY_SIZE(ts->supplies), ts->supplies); if (error) return error; msleep(ZET6223_POWER_ON_DELAY_MSEC); error = devm_add_action_or_reset(dev, zet6223_power_off, ts); if (error) { dev_err(dev, "failed to install poweroff action: %d\n", error); return error; } return 0; } static int zet6223_query_device(struct zet6223_ts *ts) { u8 buf[ZET6223_CMD_INFO_LENGTH]; u8 cmd = ZET6223_CMD_INFO; int ret; int error; ret = i2c_master_send(ts->client, &cmd, sizeof(cmd)); if (ret != sizeof(cmd)) { error = ret < 0 ? ret : -EIO; dev_err(&ts->client->dev, "touchpanel info cmd failed: %d\n", error); return error; } ret = i2c_master_recv(ts->client, buf, sizeof(buf)); if (ret != sizeof(buf)) { error = ret < 0 ? ret : -EIO; dev_err(&ts->client->dev, "failed to retrieve touchpanel info: %d\n", error); return error; } ts->fingernum = buf[15] & 0x7F; if (ts->fingernum > ZET6223_MAX_FINGERS) { dev_warn(&ts->client->dev, "touchpanel reports %d fingers, limiting to %d\n", ts->fingernum, ZET6223_MAX_FINGERS); ts->fingernum = ZET6223_MAX_FINGERS; } ts->max_x = get_unaligned_le16(&buf[8]); ts->max_y = get_unaligned_le16(&buf[10]); return 0; } static int zet6223_probe(struct i2c_client *client) { struct device *dev = &client->dev; struct zet6223_ts *ts; struct input_dev *input; int error; if (!client->irq) { dev_err(dev, "no irq specified\n"); return -EINVAL; } ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); if (!ts) return -ENOMEM; ts->client = client; error = zet6223_power_on(ts); if (error) return error; error = zet6223_query_device(ts); if (error) return error; ts->input = input = devm_input_allocate_device(dev); if (!input) return -ENOMEM; input_set_drvdata(input, ts); input->name = client->name; input->id.bustype = BUS_I2C; input->open = zet6223_start; input->close = zet6223_stop; input_set_abs_params(input, ABS_MT_POSITION_X, 0, ts->max_x, 0, 0); input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ts->max_y, 0, 0); touchscreen_parse_properties(input, true, &ts->prop); error = input_mt_init_slots(input, ts->fingernum, INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED); if (error) return error; error = devm_request_threaded_irq(dev, client->irq, NULL, zet6223_irq, IRQF_ONESHOT, client->name, ts); if (error) { dev_err(dev, "failed to request irq %d: %d\n", client->irq, error); return error; } zet6223_stop(input); error = input_register_device(input); if (error) return error; return 0; } static const struct of_device_id zet6223_of_match[] = { { .compatible = "zeitec,zet6223" }, { } }; MODULE_DEVICE_TABLE(of, zet6223_of_match); static const struct i2c_device_id zet6223_id[] = { { "zet6223", 0}, { } }; MODULE_DEVICE_TABLE(i2c, zet6223_id); static struct i2c_driver zet6223_driver = { .driver = { .name = "zet6223", .of_match_table = zet6223_of_match, }, .probe_new = zet6223_probe, .id_table = zet6223_id }; module_i2c_driver(zet6223_driver); MODULE_AUTHOR("Jelle van der Waa <jelle@vdwaa.nl>"); MODULE_DESCRIPTION("ZEITEC zet622x I2C touchscreen driver"); MODULE_LICENSE("GPL");