// SPDX-License-Identifier: GPL-2.0-or-later /* * Samsung S3C24XX touchscreen driver * * Copyright 2004 Arnaud Patard * Copyright 2008 Ben Dooks * Copyright 2009 Simtec Electronics * * Additional work by Herbert Pötzl and * Harald Welte */ #include #include #include #include #include #include #include #include #include #include #include #include #define TSC_SLEEP (S3C2410_ADCTSC_PULL_UP_DISABLE | S3C2410_ADCTSC_XY_PST(0)) #define INT_DOWN (0) #define INT_UP (1 << 8) #define WAIT4INT (S3C2410_ADCTSC_YM_SEN | \ S3C2410_ADCTSC_YP_SEN | \ S3C2410_ADCTSC_XP_SEN | \ S3C2410_ADCTSC_XY_PST(3)) #define AUTOPST (S3C2410_ADCTSC_YM_SEN | \ S3C2410_ADCTSC_YP_SEN | \ S3C2410_ADCTSC_XP_SEN | \ S3C2410_ADCTSC_AUTO_PST | \ S3C2410_ADCTSC_XY_PST(0)) #define FEAT_PEN_IRQ (1 << 0) /* HAS ADCCLRINTPNDNUP */ /* Per-touchscreen data. */ /** * struct s3c2410ts - driver touchscreen state. * @client: The ADC client we registered with the core driver. * @dev: The device we are bound to. * @input: The input device we registered with the input subsystem. * @clock: The clock for the adc. * @io: Pointer to the IO base. * @xp: The accumulated X position data. * @yp: The accumulated Y position data. * @irq_tc: The interrupt number for pen up/down interrupt * @count: The number of samples collected. * @shift: The log2 of the maximum count to read in one go. * @features: The features supported by the TSADC MOdule. */ struct s3c2410ts { struct s3c_adc_client *client; struct device *dev; struct input_dev *input; struct clk *clock; void __iomem *io; unsigned long xp; unsigned long yp; int irq_tc; int count; int shift; int features; }; static struct s3c2410ts ts; /** * get_down - return the down state of the pen * @data0: The data read from ADCDAT0 register. * @data1: The data read from ADCDAT1 register. * * Return non-zero if both readings show that the pen is down. */ static inline bool get_down(unsigned long data0, unsigned long data1) { /* returns true if both data values show stylus down */ return (!(data0 & S3C2410_ADCDAT0_UPDOWN) && !(data1 & S3C2410_ADCDAT0_UPDOWN)); } static void touch_timer_fire(struct timer_list *unused) { unsigned long data0; unsigned long data1; bool down; data0 = readl(ts.io + S3C2410_ADCDAT0); data1 = readl(ts.io + S3C2410_ADCDAT1); down = get_down(data0, data1); if (down) { if (ts.count == (1 << ts.shift)) { ts.xp >>= ts.shift; ts.yp >>= ts.shift; dev_dbg(ts.dev, "%s: X=%lu, Y=%lu, count=%d\n", __func__, ts.xp, ts.yp, ts.count); input_report_abs(ts.input, ABS_X, ts.xp); input_report_abs(ts.input, ABS_Y, ts.yp); input_report_key(ts.input, BTN_TOUCH, 1); input_sync(ts.input); ts.xp = 0; ts.yp = 0; ts.count = 0; } s3c_adc_start(ts.client, 0, 1 << ts.shift); } else { ts.xp = 0; ts.yp = 0; ts.count = 0; input_report_key(ts.input, BTN_TOUCH, 0); input_sync(ts.input); writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); } } static DEFINE_TIMER(touch_timer, touch_timer_fire); /** * stylus_irq - touchscreen stylus event interrupt * @irq: The interrupt number * @dev_id: The device ID. * * Called when the IRQ_TC is fired for a pen up or down event. */ static irqreturn_t stylus_irq(int irq, void *dev_id) { unsigned long data0; unsigned long data1; bool down; data0 = readl(ts.io + S3C2410_ADCDAT0); data1 = readl(ts.io + S3C2410_ADCDAT1); down = get_down(data0, data1); /* TODO we should never get an interrupt with down set while * the timer is running, but maybe we ought to verify that the * timer isn't running anyways. */ if (down) s3c_adc_start(ts.client, 0, 1 << ts.shift); else dev_dbg(ts.dev, "%s: count=%d\n", __func__, ts.count); if (ts.features & FEAT_PEN_IRQ) { /* Clear pen down/up interrupt */ writel(0x0, ts.io + S3C64XX_ADCCLRINTPNDNUP); } return IRQ_HANDLED; } /** * s3c24xx_ts_conversion - ADC conversion callback * @client: The client that was registered with the ADC core. * @data0: The reading from ADCDAT0. * @data1: The reading from ADCDAT1. * @left: The number of samples left. * * Called when a conversion has finished. */ static void s3c24xx_ts_conversion(struct s3c_adc_client *client, unsigned data0, unsigned data1, unsigned *left) { dev_dbg(ts.dev, "%s: %d,%d\n", __func__, data0, data1); ts.xp += data0; ts.yp += data1; ts.count++; /* From tests, it seems that it is unlikely to get a pen-up * event during the conversion process which means we can * ignore any pen-up events with less than the requisite * count done. * * In several thousand conversions, no pen-ups where detected * before count completed. */ } /** * s3c24xx_ts_select - ADC selection callback. * @client: The client that was registered with the ADC core. * @select: The reason for select. * * Called when the ADC core selects (or deslects) us as a client. */ static void s3c24xx_ts_select(struct s3c_adc_client *client, unsigned select) { if (select) { writel(S3C2410_ADCTSC_PULL_UP_DISABLE | AUTOPST, ts.io + S3C2410_ADCTSC); } else { mod_timer(&touch_timer, jiffies+1); writel(WAIT4INT | INT_UP, ts.io + S3C2410_ADCTSC); } } /** * s3c2410ts_probe - device core probe entry point * @pdev: The device we are being bound to. * * Initialise, find and allocate any resources we need to run and then * register with the ADC and input systems. */ static int s3c2410ts_probe(struct platform_device *pdev) { struct s3c2410_ts_mach_info *info; struct device *dev = &pdev->dev; struct input_dev *input_dev; struct resource *res; int ret = -EINVAL; /* Initialise input stuff */ memset(&ts, 0, sizeof(struct s3c2410ts)); ts.dev = dev; info = dev_get_platdata(dev); if (!info) { dev_err(dev, "no platform data, cannot attach\n"); return -EINVAL; } dev_dbg(dev, "initialising touchscreen\n"); ts.clock = clk_get(dev, "adc"); if (IS_ERR(ts.clock)) { dev_err(dev, "cannot get adc clock source\n"); return -ENOENT; } ret = clk_prepare_enable(ts.clock); if (ret) { dev_err(dev, "Failed! to enabled clocks\n"); goto err_clk_get; } dev_dbg(dev, "got and enabled clocks\n"); ts.irq_tc = ret = platform_get_irq(pdev, 0); if (ret < 0) { dev_err(dev, "no resource for interrupt\n"); goto err_clk; } res = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!res) { dev_err(dev, "no resource for registers\n"); ret = -ENOENT; goto err_clk; } ts.io = ioremap(res->start, resource_size(res)); if (ts.io == NULL) { dev_err(dev, "cannot map registers\n"); ret = -ENOMEM; goto err_clk; } /* inititalise the gpio */ if (info->cfg_gpio) info->cfg_gpio(to_platform_device(ts.dev)); ts.client = s3c_adc_register(pdev, s3c24xx_ts_select, s3c24xx_ts_conversion, 1); if (IS_ERR(ts.client)) { dev_err(dev, "failed to register adc client\n"); ret = PTR_ERR(ts.client); goto err_iomap; } /* Initialise registers */ if ((info->delay & 0xffff) > 0) writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY); writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); input_dev = input_allocate_device(); if (!input_dev) { dev_err(dev, "Unable to allocate the input device !!\n"); ret = -ENOMEM; goto err_iomap; } ts.input = input_dev; ts.input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); ts.input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); input_set_abs_params(ts.input, ABS_X, 0, 0x3FF, 0, 0); input_set_abs_params(ts.input, ABS_Y, 0, 0x3FF, 0, 0); ts.input->name = "S3C24XX TouchScreen"; ts.input->id.bustype = BUS_HOST; ts.input->id.vendor = 0xDEAD; ts.input->id.product = 0xBEEF; ts.input->id.version = 0x0102; ts.shift = info->oversampling_shift; ts.features = platform_get_device_id(pdev)->driver_data; ret = request_irq(ts.irq_tc, stylus_irq, 0, "s3c2410_ts_pen", ts.input); if (ret) { dev_err(dev, "cannot get TC interrupt\n"); goto err_inputdev; } dev_info(dev, "driver attached, registering input device\n"); /* All went ok, so register to the input system */ ret = input_register_device(ts.input); if (ret < 0) { dev_err(dev, "failed to register input device\n"); ret = -EIO; goto err_tcirq; } return 0; err_tcirq: free_irq(ts.irq_tc, ts.input); err_inputdev: input_free_device(ts.input); err_iomap: iounmap(ts.io); err_clk: clk_disable_unprepare(ts.clock); del_timer_sync(&touch_timer); err_clk_get: clk_put(ts.clock); return ret; } /** * s3c2410ts_remove - device core removal entry point * @pdev: The device we are being removed from. * * Free up our state ready to be removed. */ static int s3c2410ts_remove(struct platform_device *pdev) { free_irq(ts.irq_tc, ts.input); del_timer_sync(&touch_timer); clk_disable_unprepare(ts.clock); clk_put(ts.clock); input_unregister_device(ts.input); iounmap(ts.io); return 0; } #ifdef CONFIG_PM static int s3c2410ts_suspend(struct device *dev) { writel(TSC_SLEEP, ts.io + S3C2410_ADCTSC); disable_irq(ts.irq_tc); clk_disable(ts.clock); return 0; } static int s3c2410ts_resume(struct device *dev) { struct platform_device *pdev = to_platform_device(dev); struct s3c2410_ts_mach_info *info = dev_get_platdata(&pdev->dev); clk_enable(ts.clock); enable_irq(ts.irq_tc); /* Initialise registers */ if ((info->delay & 0xffff) > 0) writel(info->delay & 0xffff, ts.io + S3C2410_ADCDLY); writel(WAIT4INT | INT_DOWN, ts.io + S3C2410_ADCTSC); return 0; } static const struct dev_pm_ops s3c_ts_pmops = { .suspend = s3c2410ts_suspend, .resume = s3c2410ts_resume, }; #endif static const struct platform_device_id s3cts_driver_ids[] = { { "s3c2410-ts", 0 }, { "s3c2440-ts", 0 }, { "s3c64xx-ts", FEAT_PEN_IRQ }, { } }; MODULE_DEVICE_TABLE(platform, s3cts_driver_ids); static struct platform_driver s3c_ts_driver = { .driver = { .name = "samsung-ts", #ifdef CONFIG_PM .pm = &s3c_ts_pmops, #endif }, .id_table = s3cts_driver_ids, .probe = s3c2410ts_probe, .remove = s3c2410ts_remove, }; module_platform_driver(s3c_ts_driver); MODULE_AUTHOR("Arnaud Patard , " "Ben Dooks , " "Simtec Electronics "); MODULE_DESCRIPTION("S3C24XX Touchscreen driver"); MODULE_LICENSE("GPL v2");