From 50b6f1f4a430608f7345f66ecd68a129bff11649 Mon Sep 17 00:00:00 2001 From: Kwangwoo Lee Date: Sat, 20 Dec 2008 04:26:01 -0500 Subject: Input: add tsc2007 based touchscreen driver This drive has been tested on ARM9 based SoC - MV86XX. Signed-off-by: Kwangwoo Lee Acked-by: Jean Delvare Signed-off-by: Dmitry Torokhov --- drivers/input/touchscreen/tsc2007.c | 381 ++++++++++++++++++++++++++++++++++++ 1 file changed, 381 insertions(+) create mode 100644 drivers/input/touchscreen/tsc2007.c (limited to 'drivers/input/touchscreen/tsc2007.c') diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c new file mode 100644 index 000000000000..b75dc2990574 --- /dev/null +++ b/drivers/input/touchscreen/tsc2007.c @@ -0,0 +1,381 @@ +/* + * drivers/input/touchscreen/tsc2007.c + * + * Copyright (c) 2008 MtekVision Co., Ltd. + * Kwangwoo Lee + * + * Using code from: + * - ads7846.c + * Copyright (c) 2005 David Brownell + * Copyright (c) 2006 Nokia Corporation + * - corgi_ts.c + * Copyright (C) 2004-2005 Richard Purdie + * - omap_ts.[hc], ads7846.h, ts_osk.c + * Copyright (C) 2002 MontaVista Software + * Copyright (C) 2004 Texas Instruments + * Copyright (C) 2005 Dirk Behme + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ + +#include +#include +#include +#include +#include +#include +#include + +#define TS_POLL_DELAY (10 * 1000) /* ns delay before the first sample */ +#define TS_POLL_PERIOD (5 * 1000) /* ns delay between samples */ + +#define TSC2007_MEASURE_TEMP0 (0x0 << 4) +#define TSC2007_MEASURE_AUX (0x2 << 4) +#define TSC2007_MEASURE_TEMP1 (0x4 << 4) +#define TSC2007_ACTIVATE_XN (0x8 << 4) +#define TSC2007_ACTIVATE_YN (0x9 << 4) +#define TSC2007_ACTIVATE_YP_XN (0xa << 4) +#define TSC2007_SETUP (0xb << 4) +#define TSC2007_MEASURE_X (0xc << 4) +#define TSC2007_MEASURE_Y (0xd << 4) +#define TSC2007_MEASURE_Z1 (0xe << 4) +#define TSC2007_MEASURE_Z2 (0xf << 4) + +#define TSC2007_POWER_OFF_IRQ_EN (0x0 << 2) +#define TSC2007_ADC_ON_IRQ_DIS0 (0x1 << 2) +#define TSC2007_ADC_OFF_IRQ_EN (0x2 << 2) +#define TSC2007_ADC_ON_IRQ_DIS1 (0x3 << 2) + +#define TSC2007_12BIT (0x0 << 1) +#define TSC2007_8BIT (0x1 << 1) + +#define MAX_12BIT ((1 << 12) - 1) + +#define ADC_ON_12BIT (TSC2007_12BIT | TSC2007_ADC_ON_IRQ_DIS0) + +#define READ_Y (ADC_ON_12BIT | TSC2007_MEASURE_Y) +#define READ_Z1 (ADC_ON_12BIT | TSC2007_MEASURE_Z1) +#define READ_Z2 (ADC_ON_12BIT | TSC2007_MEASURE_Z2) +#define READ_X (ADC_ON_12BIT | TSC2007_MEASURE_X) +#define PWRDOWN (TSC2007_12BIT | TSC2007_POWER_OFF_IRQ_EN) + +struct ts_event { + u16 x; + u16 y; + u16 z1, z2; +}; + +struct tsc2007 { + struct input_dev *input; + char phys[32]; + struct hrtimer timer; + struct ts_event tc; + + struct i2c_client *client; + + spinlock_t lock; + + u16 model; + u16 x_plate_ohms; + + unsigned pendown; + int irq; + + int (*get_pendown_state)(void); + void (*clear_penirq)(void); +}; + +static inline int tsc2007_xfer(struct tsc2007 *tsc, u8 cmd) +{ + s32 data; + u16 val; + + data = i2c_smbus_read_word_data(tsc->client, cmd); + if (data < 0) { + dev_err(&tsc->client->dev, "i2c io error: %d\n", data); + return data; + } + + /* The protocol and raw data format from i2c interface: + * S Addr Wr [A] Comm [A] S Addr Rd [A] [DataLow] A [DataHigh] NA P + * Where DataLow has [D11-D4], DataHigh has [D3-D0 << 4 | Dummy 4bit]. + */ + val = swab16(data) >> 4; + + dev_dbg(&tsc->client->dev, "data: 0x%x, val: 0x%x\n", data, val); + + return val; +} + +static void tsc2007_send_event(void *tsc) +{ + struct tsc2007 *ts = tsc; + u32 rt; + u16 x, y, z1, z2; + + x = ts->tc.x; + y = ts->tc.y; + z1 = ts->tc.z1; + z2 = ts->tc.z2; + + /* range filtering */ + if (x == MAX_12BIT) + x = 0; + + if (likely(x && z1)) { + /* compute touch pressure resistance using equation #1 */ + rt = z2; + rt -= z1; + rt *= x; + rt *= ts->x_plate_ohms; + rt /= z1; + rt = (rt + 2047) >> 12; + } else + rt = 0; + + /* Sample found inconsistent by debouncing or pressure is beyond + * the maximum. Don't report it to user space, repeat at least + * once more the measurement + */ + if (rt > MAX_12BIT) { + dev_dbg(&ts->client->dev, "ignored pressure %d\n", rt); + + hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), + HRTIMER_MODE_REL); + return; + } + + /* NOTE: We can't rely on the pressure to determine the pen down + * state, even this controller has a pressure sensor. The pressure + * value can fluctuate for quite a while after lifting the pen and + * in some cases may not even settle at the expected value. + * + * The only safe way to check for the pen up condition is in the + * timer by reading the pen signal state (it's a GPIO _and_ IRQ). + */ + if (rt) { + struct input_dev *input = ts->input; + + if (!ts->pendown) { + dev_dbg(&ts->client->dev, "DOWN\n"); + + input_report_key(input, BTN_TOUCH, 1); + ts->pendown = 1; + } + + input_report_abs(input, ABS_X, x); + input_report_abs(input, ABS_Y, y); + input_report_abs(input, ABS_PRESSURE, rt); + + input_sync(input); + + dev_dbg(&ts->client->dev, "point(%4d,%4d), pressure (%4u)\n", + x, y, rt); + } + + hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD), + HRTIMER_MODE_REL); +} + +static int tsc2007_read_values(struct tsc2007 *tsc) +{ + /* y- still on; turn on only y+ (and ADC) */ + tsc->tc.y = tsc2007_xfer(tsc, READ_Y); + + /* turn y- off, x+ on, then leave in lowpower */ + tsc->tc.x = tsc2007_xfer(tsc, READ_X); + + /* turn y+ off, x- on; we'll use formula #1 */ + tsc->tc.z1 = tsc2007_xfer(tsc, READ_Z1); + tsc->tc.z2 = tsc2007_xfer(tsc, READ_Z2); + + /* power down */ + tsc2007_xfer(tsc, PWRDOWN); + + return 0; +} + +static enum hrtimer_restart tsc2007_timer(struct hrtimer *handle) +{ + struct tsc2007 *ts = container_of(handle, struct tsc2007, timer); + + spin_lock_irq(&ts->lock); + + if (unlikely(!ts->get_pendown_state() && ts->pendown)) { + struct input_dev *input = ts->input; + + dev_dbg(&ts->client->dev, "UP\n"); + + input_report_key(input, BTN_TOUCH, 0); + input_report_abs(input, ABS_PRESSURE, 0); + input_sync(input); + + ts->pendown = 0; + enable_irq(ts->irq); + } else { + /* pen is still down, continue with the measurement */ + dev_dbg(&ts->client->dev, "pen is still down\n"); + + tsc2007_read_values(ts); + tsc2007_send_event(ts); + } + + spin_unlock_irq(&ts->lock); + + return HRTIMER_NORESTART; +} + +static irqreturn_t tsc2007_irq(int irq, void *handle) +{ + struct tsc2007 *ts = handle; + unsigned long flags; + + spin_lock_irqsave(&ts->lock, flags); + + if (likely(ts->get_pendown_state())) { + disable_irq(ts->irq); + hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY), + HRTIMER_MODE_REL); + } + + if (ts->clear_penirq) + ts->clear_penirq(); + + spin_unlock_irqrestore(&ts->lock, flags); + + return IRQ_HANDLED; +} + +static int tsc2007_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct tsc2007 *ts; + struct tsc2007_platform_data *pdata = pdata = client->dev.platform_data; + struct input_dev *input_dev; + int err; + + if (!pdata) { + dev_err(&client->dev, "platform data is required!\n"); + return -EINVAL; + } + + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_READ_WORD_DATA)) + return -EIO; + + ts = kzalloc(sizeof(struct tsc2007), GFP_KERNEL); + input_dev = input_allocate_device(); + if (!ts || !input_dev) { + err = -ENOMEM; + goto err_free_mem; + } + + ts->client = client; + i2c_set_clientdata(client, ts); + + ts->input = input_dev; + + hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + ts->timer.function = tsc2007_timer; + + spin_lock_init(&ts->lock); + + ts->model = pdata->model; + ts->x_plate_ohms = pdata->x_plate_ohms; + ts->get_pendown_state = pdata->get_pendown_state; + ts->clear_penirq = pdata->clear_penirq; + + pdata->init_platform_hw(); + + snprintf(ts->phys, sizeof(ts->phys), "%s/input0", client->dev.bus_id); + + input_dev->name = "TSC2007 Touchscreen"; + input_dev->phys = ts->phys; + input_dev->id.bustype = BUS_I2C; + + input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); + input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); + + input_set_abs_params(input_dev, ABS_X, 0, MAX_12BIT, 0, 0); + input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0); + input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0); + + tsc2007_read_values(ts); + + ts->irq = client->irq; + + err = request_irq(ts->irq, tsc2007_irq, 0, + client->dev.driver->name, ts); + if (err < 0) { + dev_err(&client->dev, "irq %d busy?\n", ts->irq); + goto err_free_mem; + } + + err = input_register_device(input_dev); + if (err) + goto err_free_irq; + + dev_info(&client->dev, "registered with irq (%d)\n", ts->irq); + + return 0; + + err_free_irq: + free_irq(ts->irq, ts); + hrtimer_cancel(&ts->timer); + err_free_mem: + input_free_device(input_dev); + kfree(ts); + return err; +} + +static int tsc2007_remove(struct i2c_client *client) +{ + struct tsc2007 *ts = i2c_get_clientdata(client); + struct tsc2007_platform_data *pdata; + + pdata = client->dev.platform_data; + pdata->exit_platform_hw(); + + free_irq(ts->irq, ts); + hrtimer_cancel(&ts->timer); + input_unregister_device(ts->input); + kfree(ts); + + return 0; +} + +static struct i2c_device_id tsc2007_idtable[] = { + { "tsc2007", 0 }, + { } +}; + +MODULE_DEVICE_TABLE(i2c, tsc2007_idtable); + +static struct i2c_driver tsc2007_driver = { + .driver = { + .owner = THIS_MODULE, + .name = "tsc2007" + }, + .id_table = tsc2007_idtable, + .probe = tsc2007_probe, + .remove = tsc2007_remove, +}; + +static int __init tsc2007_init(void) +{ + return i2c_add_driver(&tsc2007_driver); +} + +static void __exit tsc2007_exit(void) +{ + i2c_del_driver(&tsc2007_driver); +} + +module_init(tsc2007_init); +module_exit(tsc2007_exit); + +MODULE_AUTHOR("Kwangwoo Lee "); +MODULE_DESCRIPTION("TSC2007 TouchScreen Driver"); +MODULE_LICENSE("GPL"); -- cgit v1.2.2