diff options
Diffstat (limited to 'drivers/input/touchscreen/zet6223.c')
| -rw-r--r-- | drivers/input/touchscreen/zet6223.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/zet6223.c b/drivers/input/touchscreen/zet6223.c new file mode 100644 index 000000000..19ffcc7b8 --- /dev/null +++ b/drivers/input/touchscreen/zet6223.c @@ -0,0 +1,268 @@ +/* + * Copyright (C) 2016, Jelle van der Waa <jelle@vdwaa.nl> + * + * 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. + * + * This program is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + */ + +#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, + const struct i2c_device_id *id) +{ + 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 = 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"); |