diff options
Diffstat (limited to 'drivers/input/touchscreen/tnetv107x-ts.c')
-rw-r--r-- | drivers/input/touchscreen/tnetv107x-ts.c | 396 |
1 files changed, 396 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/tnetv107x-ts.c b/drivers/input/touchscreen/tnetv107x-ts.c new file mode 100644 index 000000000000..cf1dba2e267c --- /dev/null +++ b/drivers/input/touchscreen/tnetv107x-ts.c @@ -0,0 +1,396 @@ +/* + * Texas Instruments TNETV107X Touchscreen Driver + * + * Copyright (C) 2010 Texas Instruments + * + * 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 version 2. + * + * This program is distributed "as is" WITHOUT ANY WARRANTY of any + * kind, whether express or implied; without even the implied warranty + * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + */ + +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/input.h> +#include <linux/platform_device.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/delay.h> +#include <linux/ctype.h> +#include <linux/io.h> +#include <linux/clk.h> + +#include <mach/tnetv107x.h> + +#define TSC_PENUP_POLL (HZ / 5) +#define IDLE_TIMEOUT 100 /* msec */ + +/* + * The first and last samples of a touch interval are usually garbage and need + * to be filtered out with these devices. The following definitions control + * the number of samples skipped. + */ +#define TSC_HEAD_SKIP 1 +#define TSC_TAIL_SKIP 1 +#define TSC_SKIP (TSC_HEAD_SKIP + TSC_TAIL_SKIP + 1) +#define TSC_SAMPLES (TSC_SKIP + 1) + +/* Register Offsets */ +struct tsc_regs { + u32 rev; + u32 tscm; + u32 bwcm; + u32 swc; + u32 adcchnl; + u32 adcdata; + u32 chval[4]; +}; + +/* TSC Mode Configuration Register (tscm) bits */ +#define WMODE BIT(0) +#define TSKIND BIT(1) +#define ZMEASURE_EN BIT(2) +#define IDLE BIT(3) +#define TSC_EN BIT(4) +#define STOP BIT(5) +#define ONE_SHOT BIT(6) +#define SINGLE BIT(7) +#define AVG BIT(8) +#define AVGNUM(x) (((x) & 0x03) << 9) +#define PVSTC(x) (((x) & 0x07) << 11) +#define PON BIT(14) +#define PONBG BIT(15) +#define AFERST BIT(16) + +/* ADC DATA Capture Register bits */ +#define DATA_VALID BIT(16) + +/* Register Access Macros */ +#define tsc_read(ts, reg) __raw_readl(&(ts)->regs->reg) +#define tsc_write(ts, reg, val) __raw_writel(val, &(ts)->regs->reg); +#define tsc_set_bits(ts, reg, val) \ + tsc_write(ts, reg, tsc_read(ts, reg) | (val)) +#define tsc_clr_bits(ts, reg, val) \ + tsc_write(ts, reg, tsc_read(ts, reg) & ~(val)) + +struct sample { + int x, y, p; +}; + +struct tsc_data { + struct input_dev *input_dev; + struct resource *res; + struct tsc_regs __iomem *regs; + struct timer_list timer; + spinlock_t lock; + struct clk *clk; + struct device *dev; + int sample_count; + struct sample samples[TSC_SAMPLES]; + int tsc_irq; +}; + +static int tsc_read_sample(struct tsc_data *ts, struct sample* sample) +{ + int x, y, z1, z2, t, p = 0; + u32 val; + + val = tsc_read(ts, chval[0]); + if (val & DATA_VALID) + x = val & 0xffff; + else + return -EINVAL; + + y = tsc_read(ts, chval[1]) & 0xffff; + z1 = tsc_read(ts, chval[2]) & 0xffff; + z2 = tsc_read(ts, chval[3]) & 0xffff; + + if (z1) { + t = ((600 * x) * (z2 - z1)); + p = t / (u32) (z1 << 12); + if (p < 0) + p = 0; + } + + sample->x = x; + sample->y = y; + sample->p = p; + + return 0; +} + +static void tsc_poll(unsigned long data) +{ + struct tsc_data *ts = (struct tsc_data *)data; + unsigned long flags; + int i, val, x, y, p; + + spin_lock_irqsave(&ts->lock, flags); + + if (ts->sample_count >= TSC_SKIP) { + input_report_abs(ts->input_dev, ABS_PRESSURE, 0); + input_report_key(ts->input_dev, BTN_TOUCH, 0); + input_sync(ts->input_dev); + } else if (ts->sample_count > 0) { + /* + * A touch event lasted less than our skip count. Salvage and + * report anyway. + */ + for (i = 0, val = 0; i < ts->sample_count; i++) + val += ts->samples[i].x; + x = val / ts->sample_count; + + for (i = 0, val = 0; i < ts->sample_count; i++) + val += ts->samples[i].y; + y = val / ts->sample_count; + + for (i = 0, val = 0; i < ts->sample_count; i++) + val += ts->samples[i].p; + p = val / ts->sample_count; + + input_report_abs(ts->input_dev, ABS_X, x); + input_report_abs(ts->input_dev, ABS_Y, y); + input_report_abs(ts->input_dev, ABS_PRESSURE, p); + input_report_key(ts->input_dev, BTN_TOUCH, 1); + input_sync(ts->input_dev); + } + + ts->sample_count = 0; + + spin_unlock_irqrestore(&ts->lock, flags); +} + +static irqreturn_t tsc_irq(int irq, void *dev_id) +{ + struct tsc_data *ts = (struct tsc_data *)dev_id; + struct sample *sample; + int index; + + spin_lock(&ts->lock); + + index = ts->sample_count % TSC_SAMPLES; + sample = &ts->samples[index]; + if (tsc_read_sample(ts, sample) < 0) + goto out; + + if (++ts->sample_count >= TSC_SKIP) { + index = (ts->sample_count - TSC_TAIL_SKIP - 1) % TSC_SAMPLES; + sample = &ts->samples[index]; + + input_report_abs(ts->input_dev, ABS_X, sample->x); + input_report_abs(ts->input_dev, ABS_Y, sample->y); + input_report_abs(ts->input_dev, ABS_PRESSURE, sample->p); + if (ts->sample_count == TSC_SKIP) + input_report_key(ts->input_dev, BTN_TOUCH, 1); + input_sync(ts->input_dev); + } + mod_timer(&ts->timer, jiffies + TSC_PENUP_POLL); +out: + spin_unlock(&ts->lock); + return IRQ_HANDLED; +} + +static int tsc_start(struct input_dev *dev) +{ + struct tsc_data *ts = input_get_drvdata(dev); + unsigned long timeout = jiffies + msecs_to_jiffies(IDLE_TIMEOUT); + u32 val; + + clk_enable(ts->clk); + + /* Go to idle mode, before any initialization */ + while (time_after(timeout, jiffies)) { + if (tsc_read(ts, tscm) & IDLE) + break; + } + + if (time_before(timeout, jiffies)) { + dev_warn(ts->dev, "timeout waiting for idle\n"); + clk_disable(ts->clk); + return -EIO; + } + + /* Configure TSC Control register*/ + val = (PONBG | PON | PVSTC(4) | ONE_SHOT | ZMEASURE_EN); + tsc_write(ts, tscm, val); + + /* Bring TSC out of reset: Clear AFE reset bit */ + val &= ~(AFERST); + tsc_write(ts, tscm, val); + + /* Configure all pins for hardware control*/ + tsc_write(ts, bwcm, 0); + + /* Finally enable the TSC */ + tsc_set_bits(ts, tscm, TSC_EN); + + return 0; +} + +static void tsc_stop(struct input_dev *dev) +{ + struct tsc_data *ts = input_get_drvdata(dev); + + tsc_clr_bits(ts, tscm, TSC_EN); + synchronize_irq(ts->tsc_irq); + del_timer_sync(&ts->timer); + clk_disable(ts->clk); +} + +static int __devinit tsc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct tsc_data *ts; + int error = 0; + u32 rev = 0; + + ts = kzalloc(sizeof(struct tsc_data), GFP_KERNEL); + if (!ts) { + dev_err(dev, "cannot allocate device info\n"); + return -ENOMEM; + } + + ts->dev = dev; + spin_lock_init(&ts->lock); + setup_timer(&ts->timer, tsc_poll, (unsigned long)ts); + platform_set_drvdata(pdev, ts); + + ts->tsc_irq = platform_get_irq(pdev, 0); + if (ts->tsc_irq < 0) { + dev_err(dev, "cannot determine device interrupt\n"); + error = -ENODEV; + goto error_res; + } + + ts->res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!ts->res) { + dev_err(dev, "cannot determine register area\n"); + error = -ENODEV; + goto error_res; + } + + if (!request_mem_region(ts->res->start, resource_size(ts->res), + pdev->name)) { + dev_err(dev, "cannot claim register memory\n"); + ts->res = NULL; + error = -EINVAL; + goto error_res; + } + + ts->regs = ioremap(ts->res->start, resource_size(ts->res)); + if (!ts->regs) { + dev_err(dev, "cannot map register memory\n"); + error = -ENOMEM; + goto error_map; + } + + ts->clk = clk_get(dev, NULL); + if (!ts->clk) { + dev_err(dev, "cannot claim device clock\n"); + error = -EINVAL; + goto error_clk; + } + + error = request_threaded_irq(ts->tsc_irq, NULL, tsc_irq, 0, + dev_name(dev), ts); + if (error < 0) { + dev_err(ts->dev, "Could not allocate ts irq\n"); + goto error_irq; + } + + ts->input_dev = input_allocate_device(); + if (!ts->input_dev) { + dev_err(dev, "cannot allocate input device\n"); + error = -ENOMEM; + goto error_input; + } + input_set_drvdata(ts->input_dev, ts); + + ts->input_dev->name = pdev->name; + ts->input_dev->id.bustype = BUS_HOST; + ts->input_dev->dev.parent = &pdev->dev; + ts->input_dev->open = tsc_start; + ts->input_dev->close = tsc_stop; + + clk_enable(ts->clk); + rev = tsc_read(ts, rev); + ts->input_dev->id.product = ((rev >> 8) & 0x07); + ts->input_dev->id.version = ((rev >> 16) & 0xfff); + clk_disable(ts->clk); + + __set_bit(EV_KEY, ts->input_dev->evbit); + __set_bit(EV_ABS, ts->input_dev->evbit); + __set_bit(BTN_TOUCH, ts->input_dev->keybit); + + input_set_abs_params(ts->input_dev, ABS_X, 0, 0xffff, 5, 0); + input_set_abs_params(ts->input_dev, ABS_Y, 0, 0xffff, 5, 0); + input_set_abs_params(ts->input_dev, ABS_PRESSURE, 0, 4095, 128, 0); + + error = input_register_device(ts->input_dev); + if (error < 0) { + dev_err(dev, "failed input device registration\n"); + goto error_reg; + } + + return 0; + +error_reg: + input_free_device(ts->input_dev); +error_input: + free_irq(ts->tsc_irq, ts); +error_irq: + clk_put(ts->clk); +error_clk: + iounmap(ts->regs); +error_map: + release_mem_region(ts->res->start, resource_size(ts->res)); +error_res: + platform_set_drvdata(pdev, NULL); + kfree(ts); + + return error; +} + +static int __devexit tsc_remove(struct platform_device *pdev) +{ + struct tsc_data *ts = platform_get_drvdata(pdev); + + input_unregister_device(ts->input_dev); + free_irq(ts->tsc_irq, ts); + clk_put(ts->clk); + iounmap(ts->regs); + release_mem_region(ts->res->start, resource_size(ts->res)); + platform_set_drvdata(pdev, NULL); + kfree(ts); + + return 0; +} + +static struct platform_driver tsc_driver = { + .probe = tsc_probe, + .remove = __devexit_p(tsc_remove), + .driver.name = "tnetv107x-ts", + .driver.owner = THIS_MODULE, +}; + +static int __init tsc_init(void) +{ + return platform_driver_register(&tsc_driver); +} + +static void __exit tsc_exit(void) +{ + platform_driver_unregister(&tsc_driver); +} + +module_init(tsc_init); +module_exit(tsc_exit); + +MODULE_AUTHOR("Cyril Chemparathy"); +MODULE_DESCRIPTION("TNETV107X Touchscreen Driver"); +MODULE_ALIAS("platform: tnetv107x-ts"); +MODULE_LICENSE("GPL"); |