| /* |
| * 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/module.h> |
| #include <linux/kernel.h> |
| #include <linux/err.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 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 (IS_ERR(ts->clk)) { |
| dev_err(dev, "cannot claim device clock\n"); |
| error = PTR_ERR(ts->clk); |
| goto error_clk; |
| } |
| |
| error = request_threaded_irq(ts->tsc_irq, NULL, tsc_irq, IRQF_ONESHOT, |
| 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: |
| kfree(ts); |
| |
| return error; |
| } |
| |
| static int 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)); |
| kfree(ts); |
| |
| return 0; |
| } |
| |
| static struct platform_driver tsc_driver = { |
| .probe = tsc_probe, |
| .remove = tsc_remove, |
| .driver.name = "tnetv107x-ts", |
| .driver.owner = THIS_MODULE, |
| }; |
| module_platform_driver(tsc_driver); |
| |
| MODULE_AUTHOR("Cyril Chemparathy"); |
| MODULE_DESCRIPTION("TNETV107X Touchscreen Driver"); |
| MODULE_ALIAS("platform:tnetv107x-ts"); |
| MODULE_LICENSE("GPL"); |