--- /dev/null
+/*
+ * Samsung S3C24XX touchscreen driver
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the term 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * Copyright 2004 Arnaud Patard <arnaud.patard@rtp-net.org>
+ * Copyright 2008 Ben Dooks <ben-linux@fluff.org>
+ * Copyright 2009 Simtec Electronics <linux@simtec.co.uk>
+ *
+ * Additional work by Herbert Pötzl <herbert@13thfloor.at> and
+ * Harald Welte <laforge@openmoko.org>
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/gpio.h>
+#include <linux/input.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <plat/adc.h>
+#include <plat/regs-adc.h>
+#include <linux/platform_data/touchscreen-s3c2410.h>
+
+#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(unsigned long data)
+{
+ 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, 0, 0);
+
+/**
+ * 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(&pdev->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;
+ }
+
+ clk_prepare_enable(ts.clock);
+ 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:
+ del_timer_sync(&touch_timer);
+ 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 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 <arnaud.patard@rtp-net.org>, "
+ "Ben Dooks <ben@simtec.co.uk>, "
+ "Simtec Electronics <linux@simtec.co.uk>");
+MODULE_DESCRIPTION("S3C24XX Touchscreen driver");
+MODULE_LICENSE("GPL v2");
Code Review / kvmfornfv.git / blobdiff