diff options
Diffstat (limited to 'drivers/input/touchscreen/st1232.c')
| -rw-r--r-- | drivers/input/touchscreen/st1232.c | 402 |
1 files changed, 402 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/st1232.c b/drivers/input/touchscreen/st1232.c new file mode 100644 index 000000000..e38ba3e4f --- /dev/null +++ b/drivers/input/touchscreen/st1232.c @@ -0,0 +1,402 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * ST1232 Touchscreen Controller Driver + * + * Copyright (C) 2010 Renesas Solutions Corp. + * Tony SIM <chinyeow.sim.xt@renesas.com> + * + * Using code from: + * - android.git.kernel.org: projects/kernel/common.git: synaptics_i2c_rmi.c + * Copyright (C) 2007 Google, Inc. + */ + +#include <linux/delay.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/module.h> +#include <linux/of.h> +#include <linux/pm_qos.h> +#include <linux/slab.h> +#include <linux/types.h> + +#define ST1232_TS_NAME "st1232-ts" +#define ST1633_TS_NAME "st1633-ts" + +#define REG_STATUS 0x01 /* Device Status | Error Code */ + +#define STATUS_NORMAL 0x00 +#define STATUS_INIT 0x01 +#define STATUS_ERROR 0x02 +#define STATUS_AUTO_TUNING 0x03 +#define STATUS_IDLE 0x04 +#define STATUS_POWER_DOWN 0x05 + +#define ERROR_NONE 0x00 +#define ERROR_INVALID_ADDRESS 0x10 +#define ERROR_INVALID_VALUE 0x20 +#define ERROR_INVALID_PLATFORM 0x30 + +#define REG_XY_RESOLUTION 0x04 +#define REG_XY_COORDINATES 0x12 +#define ST_TS_MAX_FINGERS 10 + +struct st_chip_info { + bool have_z; + u16 max_area; + u16 max_fingers; +}; + +struct st1232_ts_data { + struct i2c_client *client; + struct input_dev *input_dev; + struct touchscreen_properties prop; + struct dev_pm_qos_request low_latency_req; + struct gpio_desc *reset_gpio; + const struct st_chip_info *chip_info; + int read_buf_len; + u8 *read_buf; +}; + +static int st1232_ts_read_data(struct st1232_ts_data *ts, u8 reg, + unsigned int n) +{ + struct i2c_client *client = ts->client; + struct i2c_msg msg[] = { + { + .addr = client->addr, + .len = sizeof(reg), + .buf = ®, + }, + { + .addr = client->addr, + .flags = I2C_M_RD | I2C_M_DMA_SAFE, + .len = n, + .buf = ts->read_buf, + } + }; + int ret; + + ret = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + if (ret != ARRAY_SIZE(msg)) + return ret < 0 ? ret : -EIO; + + return 0; +} + +static int st1232_ts_wait_ready(struct st1232_ts_data *ts) +{ + unsigned int retries; + int error; + + for (retries = 100; retries; retries--) { + error = st1232_ts_read_data(ts, REG_STATUS, 1); + if (!error) { + switch (ts->read_buf[0]) { + case STATUS_NORMAL | ERROR_NONE: + case STATUS_IDLE | ERROR_NONE: + return 0; + } + } + + usleep_range(1000, 2000); + } + + return -ENXIO; +} + +static int st1232_ts_read_resolution(struct st1232_ts_data *ts, u16 *max_x, + u16 *max_y) +{ + u8 *buf; + int error; + + /* select resolution register */ + error = st1232_ts_read_data(ts, REG_XY_RESOLUTION, 3); + if (error) + return error; + + buf = ts->read_buf; + + *max_x = (((buf[0] & 0x0070) << 4) | buf[1]) - 1; + *max_y = (((buf[0] & 0x0007) << 8) | buf[2]) - 1; + + return 0; +} + +static int st1232_ts_parse_and_report(struct st1232_ts_data *ts) +{ + struct input_dev *input = ts->input_dev; + struct input_mt_pos pos[ST_TS_MAX_FINGERS]; + u8 z[ST_TS_MAX_FINGERS]; + int slots[ST_TS_MAX_FINGERS]; + int n_contacts = 0; + int i; + + for (i = 0; i < ts->chip_info->max_fingers; i++) { + u8 *buf = &ts->read_buf[i * 4]; + + if (buf[0] & BIT(7)) { + unsigned int x = ((buf[0] & 0x70) << 4) | buf[1]; + unsigned int y = ((buf[0] & 0x07) << 8) | buf[2]; + + touchscreen_set_mt_pos(&pos[n_contacts], + &ts->prop, x, y); + + /* st1232 includes a z-axis / touch strength */ + if (ts->chip_info->have_z) + z[n_contacts] = ts->read_buf[i + 6]; + + n_contacts++; + } + } + + input_mt_assign_slots(input, slots, pos, n_contacts, 0); + for (i = 0; i < n_contacts; i++) { + input_mt_slot(input, slots[i]); + input_mt_report_slot_state(input, MT_TOOL_FINGER, true); + input_report_abs(input, ABS_MT_POSITION_X, pos[i].x); + input_report_abs(input, ABS_MT_POSITION_Y, pos[i].y); + if (ts->chip_info->have_z) + input_report_abs(input, ABS_MT_TOUCH_MAJOR, z[i]); + } + + input_mt_sync_frame(input); + input_sync(input); + + return n_contacts; +} + +static irqreturn_t st1232_ts_irq_handler(int irq, void *dev_id) +{ + struct st1232_ts_data *ts = dev_id; + int count; + int error; + + error = st1232_ts_read_data(ts, REG_XY_COORDINATES, ts->read_buf_len); + if (error) + goto out; + + count = st1232_ts_parse_and_report(ts); + if (!count) { + if (ts->low_latency_req.dev) { + dev_pm_qos_remove_request(&ts->low_latency_req); + ts->low_latency_req.dev = NULL; + } + } else if (!ts->low_latency_req.dev) { + /* First contact, request 100 us latency. */ + dev_pm_qos_add_ancestor_request(&ts->client->dev, + &ts->low_latency_req, + DEV_PM_QOS_RESUME_LATENCY, 100); + } + +out: + return IRQ_HANDLED; +} + +static void st1232_ts_power(struct st1232_ts_data *ts, bool poweron) +{ + if (ts->reset_gpio) + gpiod_set_value_cansleep(ts->reset_gpio, !poweron); +} + +static void st1232_ts_power_off(void *data) +{ + st1232_ts_power(data, false); +} + +static const struct st_chip_info st1232_chip_info = { + .have_z = true, + .max_area = 0xff, + .max_fingers = 2, +}; + +static const struct st_chip_info st1633_chip_info = { + .have_z = false, + .max_area = 0x00, + .max_fingers = 5, +}; + +static int st1232_ts_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + const struct st_chip_info *match; + struct st1232_ts_data *ts; + struct input_dev *input_dev; + u16 max_x, max_y; + int error; + + match = device_get_match_data(&client->dev); + if (!match && id) + match = (const void *)id->driver_data; + if (!match) { + dev_err(&client->dev, "unknown device model\n"); + return -ENODEV; + } + + if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { + dev_err(&client->dev, "need I2C_FUNC_I2C\n"); + return -EIO; + } + + if (!client->irq) { + dev_err(&client->dev, "no IRQ?\n"); + return -EINVAL; + } + + ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + ts->chip_info = match; + + /* allocate a buffer according to the number of registers to read */ + ts->read_buf_len = ts->chip_info->max_fingers * 4; + ts->read_buf = devm_kzalloc(&client->dev, ts->read_buf_len, GFP_KERNEL); + if (!ts->read_buf) + return -ENOMEM; + + input_dev = devm_input_allocate_device(&client->dev); + if (!input_dev) + return -ENOMEM; + + ts->client = client; + ts->input_dev = input_dev; + + ts->reset_gpio = devm_gpiod_get_optional(&client->dev, NULL, + GPIOD_OUT_HIGH); + if (IS_ERR(ts->reset_gpio)) { + error = PTR_ERR(ts->reset_gpio); + dev_err(&client->dev, "Unable to request GPIO pin: %d.\n", + error); + return error; + } + + st1232_ts_power(ts, true); + + error = devm_add_action_or_reset(&client->dev, st1232_ts_power_off, ts); + if (error) { + dev_err(&client->dev, + "Failed to install power off action: %d\n", error); + return error; + } + + input_dev->name = "st1232-touchscreen"; + input_dev->id.bustype = BUS_I2C; + + /* Wait until device is ready */ + error = st1232_ts_wait_ready(ts); + if (error) + return error; + + /* Read resolution from the chip */ + error = st1232_ts_read_resolution(ts, &max_x, &max_y); + if (error) { + dev_err(&client->dev, + "Failed to read resolution: %d\n", error); + return error; + } + + if (ts->chip_info->have_z) + input_set_abs_params(input_dev, ABS_MT_TOUCH_MAJOR, 0, + ts->chip_info->max_area, 0, 0); + + input_set_abs_params(input_dev, ABS_MT_POSITION_X, + 0, max_x, 0, 0); + input_set_abs_params(input_dev, ABS_MT_POSITION_Y, + 0, max_y, 0, 0); + + touchscreen_parse_properties(input_dev, true, &ts->prop); + + error = input_mt_init_slots(input_dev, ts->chip_info->max_fingers, + INPUT_MT_DIRECT | INPUT_MT_TRACK | + INPUT_MT_DROP_UNUSED); + if (error) { + dev_err(&client->dev, "failed to initialize MT slots\n"); + return error; + } + + error = devm_request_threaded_irq(&client->dev, client->irq, + NULL, st1232_ts_irq_handler, + IRQF_ONESHOT, + client->name, ts); + if (error) { + dev_err(&client->dev, "Failed to register interrupt\n"); + return error; + } + + error = input_register_device(ts->input_dev); + if (error) { + dev_err(&client->dev, "Unable to register %s input device\n", + input_dev->name); + return error; + } + + i2c_set_clientdata(client, ts); + + return 0; +} + +static int __maybe_unused st1232_ts_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct st1232_ts_data *ts = i2c_get_clientdata(client); + + disable_irq(client->irq); + + if (!device_may_wakeup(&client->dev)) + st1232_ts_power(ts, false); + + return 0; +} + +static int __maybe_unused st1232_ts_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct st1232_ts_data *ts = i2c_get_clientdata(client); + + if (!device_may_wakeup(&client->dev)) + st1232_ts_power(ts, true); + + enable_irq(client->irq); + + return 0; +} + +static SIMPLE_DEV_PM_OPS(st1232_ts_pm_ops, + st1232_ts_suspend, st1232_ts_resume); + +static const struct i2c_device_id st1232_ts_id[] = { + { ST1232_TS_NAME, (unsigned long)&st1232_chip_info }, + { ST1633_TS_NAME, (unsigned long)&st1633_chip_info }, + { } +}; +MODULE_DEVICE_TABLE(i2c, st1232_ts_id); + +static const struct of_device_id st1232_ts_dt_ids[] = { + { .compatible = "sitronix,st1232", .data = &st1232_chip_info }, + { .compatible = "sitronix,st1633", .data = &st1633_chip_info }, + { } +}; +MODULE_DEVICE_TABLE(of, st1232_ts_dt_ids); + +static struct i2c_driver st1232_ts_driver = { + .probe = st1232_ts_probe, + .id_table = st1232_ts_id, + .driver = { + .name = ST1232_TS_NAME, + .of_match_table = st1232_ts_dt_ids, + .probe_type = PROBE_PREFER_ASYNCHRONOUS, + .pm = &st1232_ts_pm_ops, + }, +}; + +module_i2c_driver(st1232_ts_driver); + +MODULE_AUTHOR("Tony SIM <chinyeow.sim.xt@renesas.com>"); +MODULE_AUTHOR("Martin Kepplinger <martin.kepplinger@ginzinger.com>"); +MODULE_DESCRIPTION("SITRONIX ST1232 Touchscreen Controller Driver"); +MODULE_LICENSE("GPL v2"); |