| /* |
| * LPC32xx built-in touchscreen driver |
| * |
| * Copyright (C) 2010 NXP Semiconductors |
| * |
| * 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; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| */ |
| |
| #include <linux/platform_device.h> |
| #include <linux/input.h> |
| #include <linux/interrupt.h> |
| #include <linux/module.h> |
| #include <linux/clk.h> |
| #include <linux/io.h> |
| #include <linux/slab.h> |
| #include <linux/of.h> |
| |
| /* |
| * Touchscreen controller register offsets |
| */ |
| #define LPC32XX_TSC_STAT 0x00 |
| #define LPC32XX_TSC_SEL 0x04 |
| #define LPC32XX_TSC_CON 0x08 |
| #define LPC32XX_TSC_FIFO 0x0C |
| #define LPC32XX_TSC_DTR 0x10 |
| #define LPC32XX_TSC_RTR 0x14 |
| #define LPC32XX_TSC_UTR 0x18 |
| #define LPC32XX_TSC_TTR 0x1C |
| #define LPC32XX_TSC_DXP 0x20 |
| #define LPC32XX_TSC_MIN_X 0x24 |
| #define LPC32XX_TSC_MAX_X 0x28 |
| #define LPC32XX_TSC_MIN_Y 0x2C |
| #define LPC32XX_TSC_MAX_Y 0x30 |
| #define LPC32XX_TSC_AUX_UTR 0x34 |
| #define LPC32XX_TSC_AUX_MIN 0x38 |
| #define LPC32XX_TSC_AUX_MAX 0x3C |
| |
| #define LPC32XX_TSC_STAT_FIFO_OVRRN (1 << 8) |
| #define LPC32XX_TSC_STAT_FIFO_EMPTY (1 << 7) |
| |
| #define LPC32XX_TSC_SEL_DEFVAL 0x0284 |
| |
| #define LPC32XX_TSC_ADCCON_IRQ_TO_FIFO_4 (0x1 << 11) |
| #define LPC32XX_TSC_ADCCON_X_SAMPLE_SIZE(s) ((10 - (s)) << 7) |
| #define LPC32XX_TSC_ADCCON_Y_SAMPLE_SIZE(s) ((10 - (s)) << 4) |
| #define LPC32XX_TSC_ADCCON_POWER_UP (1 << 2) |
| #define LPC32XX_TSC_ADCCON_AUTO_EN (1 << 0) |
| |
| #define LPC32XX_TSC_FIFO_TS_P_LEVEL (1 << 31) |
| #define LPC32XX_TSC_FIFO_NORMALIZE_X_VAL(x) (((x) & 0x03FF0000) >> 16) |
| #define LPC32XX_TSC_FIFO_NORMALIZE_Y_VAL(y) ((y) & 0x000003FF) |
| |
| #define LPC32XX_TSC_ADCDAT_VALUE_MASK 0x000003FF |
| |
| #define LPC32XX_TSC_MIN_XY_VAL 0x0 |
| #define LPC32XX_TSC_MAX_XY_VAL 0x3FF |
| |
| #define MOD_NAME "ts-lpc32xx" |
| |
| #define tsc_readl(dev, reg) \ |
| __raw_readl((dev)->tsc_base + (reg)) |
| #define tsc_writel(dev, reg, val) \ |
| __raw_writel((val), (dev)->tsc_base + (reg)) |
| |
| struct lpc32xx_tsc { |
| struct input_dev *dev; |
| void __iomem *tsc_base; |
| int irq; |
| struct clk *clk; |
| }; |
| |
| static void lpc32xx_fifo_clear(struct lpc32xx_tsc *tsc) |
| { |
| while (!(tsc_readl(tsc, LPC32XX_TSC_STAT) & |
| LPC32XX_TSC_STAT_FIFO_EMPTY)) |
| tsc_readl(tsc, LPC32XX_TSC_FIFO); |
| } |
| |
| static irqreturn_t lpc32xx_ts_interrupt(int irq, void *dev_id) |
| { |
| u32 tmp, rv[4], xs[4], ys[4]; |
| int idx; |
| struct lpc32xx_tsc *tsc = dev_id; |
| struct input_dev *input = tsc->dev; |
| |
| tmp = tsc_readl(tsc, LPC32XX_TSC_STAT); |
| |
| if (tmp & LPC32XX_TSC_STAT_FIFO_OVRRN) { |
| /* FIFO overflow - throw away samples */ |
| lpc32xx_fifo_clear(tsc); |
| return IRQ_HANDLED; |
| } |
| |
| /* |
| * Gather and normalize 4 samples. Pen-up events may have less |
| * than 4 samples, but its ok to pop 4 and let the last sample |
| * pen status check drop the samples. |
| */ |
| idx = 0; |
| while (idx < 4 && |
| !(tsc_readl(tsc, LPC32XX_TSC_STAT) & |
| LPC32XX_TSC_STAT_FIFO_EMPTY)) { |
| tmp = tsc_readl(tsc, LPC32XX_TSC_FIFO); |
| xs[idx] = LPC32XX_TSC_ADCDAT_VALUE_MASK - |
| LPC32XX_TSC_FIFO_NORMALIZE_X_VAL(tmp); |
| ys[idx] = LPC32XX_TSC_ADCDAT_VALUE_MASK - |
| LPC32XX_TSC_FIFO_NORMALIZE_Y_VAL(tmp); |
| rv[idx] = tmp; |
| idx++; |
| } |
| |
| /* Data is only valid if pen is still down in last sample */ |
| if (!(rv[3] & LPC32XX_TSC_FIFO_TS_P_LEVEL) && idx == 4) { |
| /* Use average of 2nd and 3rd sample for position */ |
| input_report_abs(input, ABS_X, (xs[1] + xs[2]) / 2); |
| input_report_abs(input, ABS_Y, (ys[1] + ys[2]) / 2); |
| input_report_key(input, BTN_TOUCH, 1); |
| } else { |
| input_report_key(input, BTN_TOUCH, 0); |
| } |
| |
| input_sync(input); |
| |
| return IRQ_HANDLED; |
| } |
| |
| static void lpc32xx_stop_tsc(struct lpc32xx_tsc *tsc) |
| { |
| /* Disable auto mode */ |
| tsc_writel(tsc, LPC32XX_TSC_CON, |
| tsc_readl(tsc, LPC32XX_TSC_CON) & |
| ~LPC32XX_TSC_ADCCON_AUTO_EN); |
| |
| clk_disable(tsc->clk); |
| } |
| |
| static void lpc32xx_setup_tsc(struct lpc32xx_tsc *tsc) |
| { |
| u32 tmp; |
| |
| clk_enable(tsc->clk); |
| |
| tmp = tsc_readl(tsc, LPC32XX_TSC_CON) & ~LPC32XX_TSC_ADCCON_POWER_UP; |
| |
| /* Set the TSC FIFO depth to 4 samples @ 10-bits per sample (max) */ |
| tmp = LPC32XX_TSC_ADCCON_IRQ_TO_FIFO_4 | |
| LPC32XX_TSC_ADCCON_X_SAMPLE_SIZE(10) | |
| LPC32XX_TSC_ADCCON_Y_SAMPLE_SIZE(10); |
| tsc_writel(tsc, LPC32XX_TSC_CON, tmp); |
| |
| /* These values are all preset */ |
| tsc_writel(tsc, LPC32XX_TSC_SEL, LPC32XX_TSC_SEL_DEFVAL); |
| tsc_writel(tsc, LPC32XX_TSC_MIN_X, LPC32XX_TSC_MIN_XY_VAL); |
| tsc_writel(tsc, LPC32XX_TSC_MAX_X, LPC32XX_TSC_MAX_XY_VAL); |
| tsc_writel(tsc, LPC32XX_TSC_MIN_Y, LPC32XX_TSC_MIN_XY_VAL); |
| tsc_writel(tsc, LPC32XX_TSC_MAX_Y, LPC32XX_TSC_MAX_XY_VAL); |
| |
| /* Aux support is not used */ |
| tsc_writel(tsc, LPC32XX_TSC_AUX_UTR, 0); |
| tsc_writel(tsc, LPC32XX_TSC_AUX_MIN, 0); |
| tsc_writel(tsc, LPC32XX_TSC_AUX_MAX, 0); |
| |
| /* |
| * Set sample rate to about 240Hz per X/Y pair. A single measurement |
| * consists of 4 pairs which gives about a 60Hz sample rate based on |
| * a stable 32768Hz clock source. Values are in clocks. |
| * Rate is (32768 / (RTR + XCONV + RTR + YCONV + DXP + TTR + UTR) / 4 |
| */ |
| tsc_writel(tsc, LPC32XX_TSC_RTR, 0x2); |
| tsc_writel(tsc, LPC32XX_TSC_DTR, 0x2); |
| tsc_writel(tsc, LPC32XX_TSC_TTR, 0x10); |
| tsc_writel(tsc, LPC32XX_TSC_DXP, 0x4); |
| tsc_writel(tsc, LPC32XX_TSC_UTR, 88); |
| |
| lpc32xx_fifo_clear(tsc); |
| |
| /* Enable automatic ts event capture */ |
| tsc_writel(tsc, LPC32XX_TSC_CON, tmp | LPC32XX_TSC_ADCCON_AUTO_EN); |
| } |
| |
| static int lpc32xx_ts_open(struct input_dev *dev) |
| { |
| struct lpc32xx_tsc *tsc = input_get_drvdata(dev); |
| |
| lpc32xx_setup_tsc(tsc); |
| |
| return 0; |
| } |
| |
| static void lpc32xx_ts_close(struct input_dev *dev) |
| { |
| struct lpc32xx_tsc *tsc = input_get_drvdata(dev); |
| |
| lpc32xx_stop_tsc(tsc); |
| } |
| |
| static int lpc32xx_ts_probe(struct platform_device *pdev) |
| { |
| struct lpc32xx_tsc *tsc; |
| struct input_dev *input; |
| struct resource *res; |
| resource_size_t size; |
| int irq; |
| int error; |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| if (!res) { |
| dev_err(&pdev->dev, "Can't get memory resource\n"); |
| return -ENOENT; |
| } |
| |
| irq = platform_get_irq(pdev, 0); |
| if (irq < 0) { |
| dev_err(&pdev->dev, "Can't get interrupt resource\n"); |
| return irq; |
| } |
| |
| tsc = kzalloc(sizeof(*tsc), GFP_KERNEL); |
| input = input_allocate_device(); |
| if (!tsc || !input) { |
| dev_err(&pdev->dev, "failed allocating memory\n"); |
| error = -ENOMEM; |
| goto err_free_mem; |
| } |
| |
| tsc->dev = input; |
| tsc->irq = irq; |
| |
| size = resource_size(res); |
| |
| if (!request_mem_region(res->start, size, pdev->name)) { |
| dev_err(&pdev->dev, "TSC registers are not free\n"); |
| error = -EBUSY; |
| goto err_free_mem; |
| } |
| |
| tsc->tsc_base = ioremap(res->start, size); |
| if (!tsc->tsc_base) { |
| dev_err(&pdev->dev, "Can't map memory\n"); |
| error = -ENOMEM; |
| goto err_release_mem; |
| } |
| |
| tsc->clk = clk_get(&pdev->dev, NULL); |
| if (IS_ERR(tsc->clk)) { |
| dev_err(&pdev->dev, "failed getting clock\n"); |
| error = PTR_ERR(tsc->clk); |
| goto err_unmap; |
| } |
| |
| input->name = MOD_NAME; |
| input->phys = "lpc32xx/input0"; |
| input->id.bustype = BUS_HOST; |
| input->id.vendor = 0x0001; |
| input->id.product = 0x0002; |
| input->id.version = 0x0100; |
| input->dev.parent = &pdev->dev; |
| input->open = lpc32xx_ts_open; |
| input->close = lpc32xx_ts_close; |
| |
| input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); |
| input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); |
| input_set_abs_params(input, ABS_X, LPC32XX_TSC_MIN_XY_VAL, |
| LPC32XX_TSC_MAX_XY_VAL, 0, 0); |
| input_set_abs_params(input, ABS_Y, LPC32XX_TSC_MIN_XY_VAL, |
| LPC32XX_TSC_MAX_XY_VAL, 0, 0); |
| |
| input_set_drvdata(input, tsc); |
| |
| error = request_irq(tsc->irq, lpc32xx_ts_interrupt, |
| 0, pdev->name, tsc); |
| if (error) { |
| dev_err(&pdev->dev, "failed requesting interrupt\n"); |
| goto err_put_clock; |
| } |
| |
| error = input_register_device(input); |
| if (error) { |
| dev_err(&pdev->dev, "failed registering input device\n"); |
| goto err_free_irq; |
| } |
| |
| platform_set_drvdata(pdev, tsc); |
| device_init_wakeup(&pdev->dev, 1); |
| |
| return 0; |
| |
| err_free_irq: |
| free_irq(tsc->irq, tsc); |
| err_put_clock: |
| clk_put(tsc->clk); |
| err_unmap: |
| iounmap(tsc->tsc_base); |
| err_release_mem: |
| release_mem_region(res->start, size); |
| err_free_mem: |
| input_free_device(input); |
| kfree(tsc); |
| |
| return error; |
| } |
| |
| static int lpc32xx_ts_remove(struct platform_device *pdev) |
| { |
| struct lpc32xx_tsc *tsc = platform_get_drvdata(pdev); |
| struct resource *res; |
| |
| device_init_wakeup(&pdev->dev, 0); |
| free_irq(tsc->irq, tsc); |
| |
| input_unregister_device(tsc->dev); |
| |
| clk_put(tsc->clk); |
| |
| iounmap(tsc->tsc_base); |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| release_mem_region(res->start, resource_size(res)); |
| |
| kfree(tsc); |
| |
| return 0; |
| } |
| |
| #ifdef CONFIG_PM |
| static int lpc32xx_ts_suspend(struct device *dev) |
| { |
| struct lpc32xx_tsc *tsc = dev_get_drvdata(dev); |
| struct input_dev *input = tsc->dev; |
| |
| /* |
| * Suspend and resume can be called when the device hasn't been |
| * enabled. If there are no users that have the device open, then |
| * avoid calling the TSC stop and start functions as the TSC |
| * isn't yet clocked. |
| */ |
| mutex_lock(&input->mutex); |
| |
| if (input->users) { |
| if (device_may_wakeup(dev)) |
| enable_irq_wake(tsc->irq); |
| else |
| lpc32xx_stop_tsc(tsc); |
| } |
| |
| mutex_unlock(&input->mutex); |
| |
| return 0; |
| } |
| |
| static int lpc32xx_ts_resume(struct device *dev) |
| { |
| struct lpc32xx_tsc *tsc = dev_get_drvdata(dev); |
| struct input_dev *input = tsc->dev; |
| |
| mutex_lock(&input->mutex); |
| |
| if (input->users) { |
| if (device_may_wakeup(dev)) |
| disable_irq_wake(tsc->irq); |
| else |
| lpc32xx_setup_tsc(tsc); |
| } |
| |
| mutex_unlock(&input->mutex); |
| |
| return 0; |
| } |
| |
| static const struct dev_pm_ops lpc32xx_ts_pm_ops = { |
| .suspend = lpc32xx_ts_suspend, |
| .resume = lpc32xx_ts_resume, |
| }; |
| #define LPC32XX_TS_PM_OPS (&lpc32xx_ts_pm_ops) |
| #else |
| #define LPC32XX_TS_PM_OPS NULL |
| #endif |
| |
| #ifdef CONFIG_OF |
| static const struct of_device_id lpc32xx_tsc_of_match[] = { |
| { .compatible = "nxp,lpc3220-tsc", }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, lpc32xx_tsc_of_match); |
| #endif |
| |
| static struct platform_driver lpc32xx_ts_driver = { |
| .probe = lpc32xx_ts_probe, |
| .remove = lpc32xx_ts_remove, |
| .driver = { |
| .name = MOD_NAME, |
| .owner = THIS_MODULE, |
| .pm = LPC32XX_TS_PM_OPS, |
| .of_match_table = of_match_ptr(lpc32xx_tsc_of_match), |
| }, |
| }; |
| module_platform_driver(lpc32xx_ts_driver); |
| |
| MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com"); |
| MODULE_DESCRIPTION("LPC32XX TSC Driver"); |
| MODULE_LICENSE("GPL"); |
| MODULE_ALIAS("platform:lpc32xx_ts"); |