diff options
Diffstat (limited to 'drivers/input/touchscreen/tsc2007.c')
| -rw-r--r-- | drivers/input/touchscreen/tsc2007.c | 443 |
1 files changed, 443 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/tsc2007.c b/drivers/input/touchscreen/tsc2007.c new file mode 100644 index 000000000000..6e18ffbebd47 --- /dev/null +++ b/drivers/input/touchscreen/tsc2007.c @@ -0,0 +1,443 @@ +/* + * Copyright 2008-2009 Freescale Semiconductor, Inc. All Rights Reserved. + */ + +/* + * The code contained herein is licensed under the GNU General Public + * License. You may obtain a copy of the GNU General Public License + * Version 2 or later at the following locations: + * + * http://www.opensource.org/licenses/gpl-license.html + * http://www.gnu.org/copyleft/gpl.html + */ + +/*! + * @file tsc2007.c + * + * @brief Driver for TI's tsc2007 I2C Touch Screen Controller. + * + * This driver is based on the driver written by Bill Gatliff + * Copyright (C) 2005 Bill Gatliff <bgat at billgatliff.com> + * Changes for 2.6.20 kernel by Nicholas Chen <nchen at cs.umd.edu> + * + * @ingroup touchscreen + */ + +#include <linux/module.h> +#include <linux/init.h> +#include <linux/slab.h> +#include <linux/i2c.h> +#include <linux/string.h> +#include <linux/bcd.h> +#include <linux/list.h> +#include <linux/device.h> +#include <linux/interrupt.h> +#include <linux/kthread.h> +#include <linux/input.h> +#include <linux/delay.h> +#include <linux/regulator/consumer.h> +#include <asm/mach/irq.h> + +#define DRIVER_NAME "tsc2007" + +enum tsc2007_pd { + PD_POWERDOWN = 0, /* penirq */ + PD_IREFOFF_ADCON = 1, /* no penirq */ + PD_IREFON_ADCOFF = 2, /* penirq */ + PD_IREFON_ADCON = 3, /* no penirq */ + PD_PENIRQ_ARM = PD_IREFON_ADCOFF, + PD_PENIRQ_DISARM = PD_IREFON_ADCON, +}; + +enum tsc2007_m { + M_12BIT = 0, + M_8BIT = 1 +}; + +enum tsc2007_cmd { + MEAS_TEMP0 = 0, + MEAS_IN1 = 2, + MEAS_XPOS = 12, + MEAS_YPOS = 13, + MEAS_Z1POS = 14, + MEAS_Z2POS = 15 +}; + +#define tsc2007_CMD(cn, pdn, m) (((cn) << 4) | ((pdn) << 2) | ((m) << 1)) + +#define ADC_MAX ((1 << 12) - 1) + +struct tsc2007_data { + struct i2c_client *client; + struct input_dev *idev; + struct timer_list penirq_timer; + struct task_struct *tstask; + u32 ts_thread_cnt; + struct completion penirq_completion; + struct completion penup_completion; + enum tsc2007_m m; + int penirq; + int penup_threshold; + struct regulator *vdd_reg; + int opened; +}; + +static int tsc2007_read(struct tsc2007_data *data, + enum tsc2007_cmd cmd, enum tsc2007_pd pd, int *val) +{ + unsigned char c; + unsigned char d[2]; + int ret; + + c = tsc2007_CMD(cmd, pd, data->m); + + ret = i2c_master_send(data->client, &c, 1); + + if (ret < 0) + goto err; + + udelay(20); + ret = i2c_master_recv(data->client, d, data->m == M_12BIT ? 2 : 1); + if (ret < 0) + goto err; + + if (val) { + *val = d[0]; + *val <<= 4; + if (data->m == M_12BIT) + *val += (d[1] >> 4); + } + + return 0; + err: + return -ENODEV; +} + +static inline int tsc2007_read_xpos(struct tsc2007_data *d, enum + tsc2007_pd pd, int *x) +{ + return tsc2007_read(d, MEAS_XPOS, pd, x); +} + +static inline int tsc2007_read_ypos(struct tsc2007_data *d, enum + tsc2007_pd pd, int *y) +{ + return tsc2007_read(d, MEAS_YPOS, pd, y); +} + +static inline int tsc2007_read_pressure(struct tsc2007_data *d, enum + tsc2007_pd pd, int *p) +{ + return tsc2007_read(d, MEAS_Z1POS, pd, p); +} + +static inline int tsc2007_powerdown(struct tsc2007_data *d) +{ + /* we don't have a distinct powerdown command, + so do a benign read with the PD bits cleared */ + return tsc2007_read(d, MEAS_IN1, PD_POWERDOWN, 0); +} + +#define PENUP_TIMEOUT 10 + +static irqreturn_t tsc2007_penirq(int irq, void *v) +{ + struct tsc2007_data *d = v; + + disable_irq(d->penirq); + complete(&d->penirq_completion); + return IRQ_HANDLED; +} + +static void tsc2007_pen_up(unsigned long v) +{ + struct tsc2007_data *d = (struct tsc2007_data *)v; + + complete(&d->penup_completion); + return; +} + +static inline void tsc2007_restart_pen_up_timer(struct tsc2007_data *d) +{ + mod_timer(&d->penirq_timer, jiffies + (PENUP_TIMEOUT * HZ) / 1000); +} + +static int tsc2007ts_thread(void *v) +{ + struct tsc2007_data *d = v; + + if (d->ts_thread_cnt) + return -EINVAL; + d->ts_thread_cnt = 1; + + while (1) { + unsigned int x = 0, y = 0, p = 0; + + if (kthread_should_stop()) + break; + /* Wait for an Pen down interrupt */ + if (wait_for_completion_interruptible_timeout + (&d->penirq_completion, HZ) <= 0) + continue; + + tsc2007_read_xpos(d, PD_PENIRQ_DISARM, &x); + tsc2007_read_ypos(d, PD_PENIRQ_DISARM, &y); + tsc2007_read_pressure(d, PD_PENIRQ_DISARM, &p); + input_report_abs(d->idev, ABS_X, 4096 - x); + input_report_abs(d->idev, ABS_Y, 4096 - y); + input_report_abs(d->idev, ABS_PRESSURE, p); + input_sync(d->idev); + + while (p > d->penup_threshold) { + tsc2007_restart_pen_up_timer(d); + wait_for_completion_interruptible(&d->penup_completion); + /* Pen Down */ + tsc2007_read_xpos(d, PD_PENIRQ_DISARM, &x); + tsc2007_read_ypos(d, PD_PENIRQ_DISARM, &y); + tsc2007_read_pressure(d, PD_PENIRQ_DISARM, &p); + if (p <= d->penup_threshold) + break; + + input_report_abs(d->idev, ABS_X, 4096 - x); + input_report_abs(d->idev, ABS_Y, 4096 - y); + input_report_abs(d->idev, ABS_PRESSURE, p); + input_sync(d->idev); + }; + + /* Pen Up */ + input_report_abs(d->idev, ABS_X, 4096 - x); + input_report_abs(d->idev, ABS_Y, 4096 - y); + input_report_abs(d->idev, ABS_PRESSURE, 0); + input_sync(d->idev); + + tsc2007_read(d, MEAS_TEMP0, PD_PENIRQ_ARM, 0); + enable_irq(d->penirq); + + } + + d->ts_thread_cnt = 0; + return 0; +} + +/*! + * This function puts the touch screen controller in low-power mode/state. + * + * @param pdev the device structure used to give information on touch screen + * to suspend + * @param state the power state the device is entering + * + * @return The function always returns 0. + */ +static int tsc2007_suspend(struct i2c_client *client, pm_message_t state) +{ + struct tsc2007_data *d = i2c_get_clientdata(client); + + if (!IS_ERR(d->tstask) && d->opened) + kthread_stop(d->tstask); + + return 0; +} + +/*! + * This function brings the touch screen controller back from low-power state. + * + * @param pdev the device structure used to give information on touch screen + * to resume + * + * @return The function always returns 0. + */ +static int tsc2007_resume(struct i2c_client *client) +{ + struct tsc2007_data *d = i2c_get_clientdata(client); + + if (d->opened) + d->tstask = kthread_run(tsc2007ts_thread, d, DRIVER_NAME "tsd"); + + return 0; +} + +static int tsc2007_idev_open(struct input_dev *idev) +{ + struct tsc2007_data *d = input_get_drvdata(idev); + int ret = 0; + + d->penirq_timer.data = (unsigned long)d; + d->penirq_timer.function = tsc2007_pen_up; + + init_completion(&d->penup_completion); + + d->tstask = kthread_run(tsc2007ts_thread, d, DRIVER_NAME "tsd"); + if (IS_ERR(d->tstask)) + ret = PTR_ERR(d->tstask); + else + d->opened++; + + return ret; +} + +static void tsc2007_idev_close(struct input_dev *idev) +{ + struct tsc2007_data *d = input_get_drvdata(idev); + if (!IS_ERR(d->tstask)) + kthread_stop(d->tstask); + + del_timer_sync(&d->penirq_timer); + + if (d->opened > 0) + d->opened--; +} + +static int tsc2007_driver_register(struct tsc2007_data *data) +{ + struct input_dev *idev; + int ret = 0; + + init_timer(&data->penirq_timer); + data->penirq_timer.data = (unsigned long)data; + data->penirq_timer.function = tsc2007_pen_up; + + init_completion(&data->penirq_completion); + + if (data->penirq) { + ret = + request_irq(data->penirq, tsc2007_penirq, IRQF_TRIGGER_LOW, + DRIVER_NAME, data); + if (!ret) { + printk(KERN_INFO "%s: Registering Touchscreen device\n", + __func__); + set_irq_wake(data->penirq, 1); + } else { + printk(KERN_ERR "%s: Cannot grab irq %d\n", + __func__, data->penirq); + } + } + idev = input_allocate_device(); + data->idev = idev; + input_set_drvdata(idev, data); + idev->name = DRIVER_NAME; + idev->evbit[0] = BIT(EV_ABS); + idev->open = tsc2007_idev_open; + idev->close = tsc2007_idev_close; + idev->absbit[0] = BIT(ABS_X) | BIT(ABS_Y) | BIT(ABS_PRESSURE); + input_set_abs_params(idev, ABS_X, 0, ADC_MAX, 0, 0); + input_set_abs_params(idev, ABS_Y, 0, ADC_MAX, 0, 0); + input_set_abs_params(idev, ABS_PRESSURE, 0, 0, 0, 0); + + if (!ret) + ret = input_register_device(idev); + + return ret; +} + +static int tsc2007_i2c_remove(struct i2c_client *client) +{ + int err; + struct tsc2007_data *d = i2c_get_clientdata(client); + struct mxc_tsc_platform_data *tsc_data; + + free_irq(d->penirq, d); + input_unregister_device(d->idev); + + err = i2c_detach_client(client); + if (err) { + dev_err(&client->dev, "Client deregistration failed, " + "client not detached.\n"); + return err; + } + + tsc_data = (struct mxc_tsc_platform_data *)(client->dev).platform_data; + if (tsc_data && tsc_data->inactive) + tsc_data->inactive(); + + if (d->vdd_reg) { + regulator_disable(d->vdd_reg); + regulator_put(d->vdd_reg); + d->vdd_reg = NULL; + } + return 0; +} + +static int tsc2007_i2c_probe(struct i2c_client *client, const struct i2c_device_id *id) +{ + struct tsc2007_data *data; + struct mxc_tsc_platform_data *tsc_data; + int err = 0; + + data = kzalloc(sizeof(struct tsc2007_data), GFP_KERNEL); + if (data == NULL) + return -ENOMEM; + + i2c_set_clientdata(client, data); + data->client = client; + data->penirq = client->irq; + + tsc_data = (struct mxc_tsc_platform_data *)(client->dev).platform_data; + if (tsc_data && tsc_data->vdd_reg) { + if (tsc_data->penup_threshold > (ADC_MAX >> 3)) + data->penup_threshold = (ADC_MAX >> 3); + else if (tsc_data->penup_threshold > 0) + data->penup_threshold = tsc_data->penup_threshold; + else + data->penup_threshold = 10; + + data->vdd_reg = regulator_get(&client->dev, tsc_data->vdd_reg); + if (!IS_ERR(data->vdd_reg)) + regulator_enable(data->vdd_reg); + else + data->vdd_reg = NULL; + if (tsc_data->active) + tsc_data->active(); + } else { + data->vdd_reg = NULL; + data->penup_threshold = 10; + } + + err = tsc2007_powerdown(data); + if (err >= 0) { + data->m = M_12BIT; + + err = tsc2007_driver_register(data); + if (err < 0) + goto exit; + + return 0; + } + + exit: + return err; +} + +static const struct i2c_device_id tsc2007_id[] = { + { "tsc2007", 0 }, + {}, +}; +MODULE_DEVICE_TABLE(i2c, tsc2007_id); + +static struct i2c_driver tsc2007_driver = { + .driver = { + .name = DRIVER_NAME, + }, + .probe = tsc2007_i2c_probe, + .remove = tsc2007_i2c_remove, + .suspend = tsc2007_suspend, + .resume = tsc2007_resume, + .command = NULL, + .id_table = tsc2007_id, +}; + +static int __init tsc2007_init(void) +{ + return i2c_add_driver(&tsc2007_driver); +} + +static void __exit tsc2007_exit(void) +{ + i2c_del_driver(&tsc2007_driver); +} + +MODULE_AUTHOR("Freescale Semiconductor, Inc."); +MODULE_DESCRIPTION("tsc2007 Touch Screen Controller driver"); +MODULE_LICENSE("GPL"); + +module_init(tsc2007_init); +module_exit(tsc2007_exit); |