1 files changed, 464 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/s3c2410_ts.c b/drivers/input/touchscreen/s3c2410_ts.c
new file mode 100644
index 000000000..2e70c0b79
--- /dev/null
+++ b/drivers/input/touchscreen/s3c2410_ts.c
@@ -0,0 +1,464 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Samsung S3C24XX touchscreen driver
+ *
+ * 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/input.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include <linux/soc/samsung/s3c-adc.h>
+#include <linux/platform_data/touchscreen-s3c2410.h>
+
+#define	S3C2410_ADCCON			(0x00)
+#define	S3C2410_ADCTSC			(0x04)
+#define	S3C2410_ADCDLY			(0x08)
+#define	S3C2410_ADCDAT0			(0x0C)
+#define	S3C2410_ADCDAT1			(0x10)
+#define	S3C64XX_ADCUPDN			(0x14)
+#define	S3C2443_ADCMUX			(0x18)
+#define	S3C64XX_ADCCLRINT		(0x18)
+#define	S5P_ADCMUX			(0x1C)
+#define	S3C64XX_ADCCLRINTPNDNUP		(0x20)
+
+/* ADCTSC Register Bits */
+#define S3C2443_ADCTSC_UD_SEN		(1 << 8)
+#define S3C2410_ADCTSC_YM_SEN		(1<<7)
+#define S3C2410_ADCTSC_YP_SEN		(1<<6)
+#define S3C2410_ADCTSC_XM_SEN		(1<<5)
+#define S3C2410_ADCTSC_XP_SEN		(1<<4)
+#define S3C2410_ADCTSC_PULL_UP_DISABLE	(1<<3)
+#define S3C2410_ADCTSC_AUTO_PST		(1<<2)
+#define S3C2410_ADCTSC_XY_PST(x)	(((x)&0x3)<<0)
+
+/* ADCDAT0 Bits */
+#define S3C2410_ADCDAT0_UPDOWN		(1<<15)
+#define S3C2410_ADCDAT0_AUTO_PST	(1<<14)
+#define S3C2410_ADCDAT0_XY_PST		(0x3<<12)
+#define S3C2410_ADCDAT0_XPDATA_MASK	(0x03FF)
+
+/* ADCDAT1 Bits */
+#define S3C2410_ADCDAT1_UPDOWN		(1<<15)
+#define S3C2410_ADCDAT1_AUTO_PST	(1<<14)
+#define S3C2410_ADCDAT1_XY_PST		(0x3<<12)
+#define S3C2410_ADCDAT1_YPDATA_MASK	(0x03FF)
+
+
+#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 <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");