Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit f94add3b authored Jul 02, 2010 by Luotao Fu Committed by Samuel Ortiz Aug 12, 2010

input: STMPE touch controller support



This one adds a driver for STMPE touchscreen controllers.
This driver depends on the stmpexxx mfd core driver.

Signed-off-by: Luotao Fu <l.fu@pengutronix.de>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>

parent 76f10845

drivers/input/touchscreen/Kconfig

+10 −0

Original line number	Diff line number	Diff line
		@@ -628,4 +628,14 @@ config TOUCHSCREEN_TPS6507X
		To compile this driver as a module, choose M here: the
		module will be called tps6507x_ts.

		config TOUCHSCREEN_STMPE
		tristate "STMicroelectronics STMPE touchscreens"
		depends on MFD_STMPE
		help
		Say Y here if you want support for STMicroelectronics
		STMPE touchscreen controllers.

		To compile this driver as a module, choose M here: the
		module will be called stmpe-ts.

		endif

drivers/input/touchscreen/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -36,6 +36,7 @@ obj-$(CONFIG_TOUCHSCREEN_PCAP) += pcap_ts.o
		obj-$(CONFIG_TOUCHSCREEN_PENMOUNT) += penmount.o
		obj-$(CONFIG_TOUCHSCREEN_QT602240) += qt602240_ts.o
		obj-$(CONFIG_TOUCHSCREEN_S3C2410) += s3c2410_ts.o
		obj-$(CONFIG_TOUCHSCREEN_STMPE) += stmpe-ts.o
		obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213) += touchit213.o
		obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT) += touchright.o
		obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN) += touchwin.o

drivers/input/touchscreen/stmpe-ts.c

0 → 100644

+397 −0

Original line number	Diff line number	Diff line
		/* STMicroelectronics STMPE811 Touchscreen Driver
		*
		* (C) 2010 Luotao Fu <l.fu@pengutronix.de>
		* All rights reserved.
		*
		* 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.
		*
		*/

		#include <linux/kernel.h>
		#include <linux/module.h>
		#include <linux/sched.h>
		#include <linux/interrupt.h>
		#include <linux/init.h>
		#include <linux/device.h>
		#include <linux/platform_device.h>
		#include <linux/input.h>
		#include <linux/slab.h>
		#include <linux/delay.h>
		#include <linux/i2c.h>
		#include <linux/workqueue.h>

		#include <linux/mfd/stmpe.h>

		/* Register layouts and functionalities are identical on all stmpexxx variants
		* with touchscreen controller
		*/
		#define STMPE_REG_INT_STA 0x0B
		#define STMPE_REG_ADC_CTRL1 0x20
		#define STMPE_REG_ADC_CTRL2 0x21
		#define STMPE_REG_TSC_CTRL 0x40
		#define STMPE_REG_TSC_CFG 0x41
		#define STMPE_REG_FIFO_TH 0x4A
		#define STMPE_REG_FIFO_STA 0x4B
		#define STMPE_REG_FIFO_SIZE 0x4C
		#define STMPE_REG_TSC_DATA_XYZ 0x52
		#define STMPE_REG_TSC_FRACTION_Z 0x56
		#define STMPE_REG_TSC_I_DRIVE 0x58

		#define OP_MOD_XYZ 0

		#define STMPE_TSC_CTRL_TSC_EN (1<<0)

		#define STMPE_FIFO_STA_RESET (1<<0)

		#define STMPE_IRQ_TOUCH_DET 0

		#define SAMPLE_TIME(x) ((x & 0xf) << 4)
		#define MOD_12B(x) ((x & 0x1) << 3)
		#define REF_SEL(x) ((x & 0x1) << 1)
		#define ADC_FREQ(x) (x & 0x3)
		#define AVE_CTRL(x) ((x & 0x3) << 6)
		#define DET_DELAY(x) ((x & 0x7) << 3)
		#define SETTLING(x) (x & 0x7)
		#define FRACTION_Z(x) (x & 0x7)
		#define I_DRIVE(x) (x & 0x1)
		#define OP_MODE(x) ((x & 0x7) << 1)

		#define STMPE_TS_NAME "stmpe-ts"
		#define XY_MASK 0xfff

		struct stmpe_touch {
		struct stmpe *stmpe;
		struct input_dev *idev;
		struct delayed_work work;
		struct device *dev;
		u8 sample_time;
		u8 mod_12b;
		u8 ref_sel;
		u8 adc_freq;
		u8 ave_ctrl;
		u8 touch_det_delay;
		u8 settling;
		u8 fraction_z;
		u8 i_drive;
		};

		static int __stmpe_reset_fifo(struct stmpe *stmpe)
		{
		int ret;

		ret = stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA,
		STMPE_FIFO_STA_RESET, STMPE_FIFO_STA_RESET);
		if (ret)
		return ret;

		return stmpe_set_bits(stmpe, STMPE_REG_FIFO_STA,
		STMPE_FIFO_STA_RESET, 0);
		}

		static void stmpe_work(struct work_struct *work)
		{
		int int_sta;
		u32 timeout = 40;

		struct stmpe_touch *ts =
		container_of(work, struct stmpe_touch, work.work);

		int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA);

		/*
		* touch_det sometimes get desasserted or just get stuck. This appears
		* to be a silicon bug, We still have to clearify this with the
		* manufacture. As a workaround We release the key anyway if the
		* touch_det keeps coming in after 4ms, while the FIFO contains no value
		* during the whole time.
		*/
		while ((int_sta & (1 << STMPE_IRQ_TOUCH_DET)) && (timeout > 0)) {
		timeout--;
		int_sta = stmpe_reg_read(ts->stmpe, STMPE_REG_INT_STA);
		udelay(100);
		}

		/* reset the FIFO before we report release event */
		__stmpe_reset_fifo(ts->stmpe);

		input_report_abs(ts->idev, ABS_PRESSURE, 0);
		input_sync(ts->idev);
		}

		static irqreturn_t stmpe_ts_handler(int irq, void *data)
		{
		u8 data_set[4];
		int x, y, z;
		struct stmpe_touch *ts = data;

		/*
		* Cancel scheduled polling for release if we have new value
		* available. Wait if the polling is already running.
		*/
		cancel_delayed_work_sync(&ts->work);

		/*
		* The FIFO sometimes just crashes and stops generating interrupts. This
		* appears to be a silicon bug. We still have to clearify this with
		* the manufacture. As a workaround we disable the TSC while we are
		* collecting data and flush the FIFO after reading
		*/
		stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
		STMPE_TSC_CTRL_TSC_EN, 0);

		stmpe_block_read(ts->stmpe, STMPE_REG_TSC_DATA_XYZ, 4, data_set);

		x = (data_set[0] << 4) \| (data_set[1] >> 4);
		y = ((data_set[1] & 0xf) << 8) \| data_set[2];
		z = data_set[3];

		input_report_abs(ts->idev, ABS_X, x);
		input_report_abs(ts->idev, ABS_Y, y);
		input_report_abs(ts->idev, ABS_PRESSURE, z);
		input_sync(ts->idev);

		/* flush the FIFO after we have read out our values. */
		__stmpe_reset_fifo(ts->stmpe);

		/* reenable the tsc */
		stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
		STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN);

		/* start polling for touch_det to detect release */
		schedule_delayed_work(&ts->work, HZ / 50);

		return IRQ_HANDLED;
		}

		static int __devinit stmpe_init_hw(struct stmpe_touch *ts)
		{
		int ret;
		u8 adc_ctrl1, adc_ctrl1_mask, tsc_cfg, tsc_cfg_mask;
		struct stmpe *stmpe = ts->stmpe;
		struct device *dev = ts->dev;

		ret = stmpe_enable(stmpe, STMPE_BLOCK_TOUCHSCREEN \| STMPE_BLOCK_ADC);
		if (ret) {
		dev_err(dev, "Could not enable clock for ADC and TS\n");
		return ret;
		}

		adc_ctrl1 = SAMPLE_TIME(ts->sample_time) \| MOD_12B(ts->mod_12b) \|
		REF_SEL(ts->ref_sel);
		adc_ctrl1_mask = SAMPLE_TIME(0xff) \| MOD_12B(0xff) \| REF_SEL(0xff);

		ret = stmpe_set_bits(stmpe, STMPE_REG_ADC_CTRL1,
		adc_ctrl1_mask, adc_ctrl1);
		if (ret) {
		dev_err(dev, "Could not setup ADC\n");
		return ret;
		}

		ret = stmpe_set_bits(stmpe, STMPE_REG_ADC_CTRL2,
		ADC_FREQ(0xff), ADC_FREQ(ts->adc_freq));
		if (ret) {
		dev_err(dev, "Could not setup ADC\n");
		return ret;
		}

		tsc_cfg = AVE_CTRL(ts->ave_ctrl) \| DET_DELAY(ts->touch_det_delay) \|
		SETTLING(ts->settling);
		tsc_cfg_mask = AVE_CTRL(0xff) \| DET_DELAY(0xff) \| SETTLING(0xff);

		ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CFG, tsc_cfg_mask, tsc_cfg);
		if (ret) {
		dev_err(dev, "Could not config touch\n");
		return ret;
		}

		ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_FRACTION_Z,
		FRACTION_Z(0xff), FRACTION_Z(ts->fraction_z));
		if (ret) {
		dev_err(dev, "Could not config touch\n");
		return ret;
		}

		ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_I_DRIVE,
		I_DRIVE(0xff), I_DRIVE(ts->i_drive));
		if (ret) {
		dev_err(dev, "Could not config touch\n");
		return ret;
		}

		/* set FIFO to 1 for single point reading */
		ret = stmpe_reg_write(stmpe, STMPE_REG_FIFO_TH, 1);
		if (ret) {
		dev_err(dev, "Could not set FIFO\n");
		return ret;
		}

		ret = stmpe_set_bits(stmpe, STMPE_REG_TSC_CTRL,
		OP_MODE(0xff), OP_MODE(OP_MOD_XYZ));
		if (ret) {
		dev_err(dev, "Could not set mode\n");
		return ret;
		}

		return 0;
		}

		static int stmpe_ts_open(struct input_dev *dev)
		{
		struct stmpe_touch *ts = input_get_drvdata(dev);
		int ret = 0;

		ret = __stmpe_reset_fifo(ts->stmpe);
		if (ret)
		return ret;

		return stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
		STMPE_TSC_CTRL_TSC_EN, STMPE_TSC_CTRL_TSC_EN);
		}

		static void stmpe_ts_close(struct input_dev *dev)
		{
		struct stmpe_touch *ts = input_get_drvdata(dev);

		cancel_delayed_work_sync(&ts->work);

		stmpe_set_bits(ts->stmpe, STMPE_REG_TSC_CTRL,
		STMPE_TSC_CTRL_TSC_EN, 0);
		}

		static int __devinit stmpe_input_probe(struct platform_device *pdev)
		{
		struct stmpe *stmpe = dev_get_drvdata(pdev->dev.parent);
		struct stmpe_platform_data *pdata = stmpe->pdata;
		struct stmpe_touch *ts;
		struct input_dev *idev;
		struct stmpe_ts_platform_data *ts_pdata = NULL;
		int ret = 0;
		unsigned int ts_irq;

		ts_irq = platform_get_irq_byname(pdev, "FIFO_TH");
		if (ts_irq < 0)
		return ts_irq;

		ts = kzalloc(sizeof(*ts), GFP_KERNEL);
		if (!ts)
		goto err_out;

		idev = input_allocate_device();
		if (!idev)
		goto err_free_ts;

		platform_set_drvdata(pdev, ts);
		ts->stmpe = stmpe;
		ts->idev = idev;
		ts->dev = &pdev->dev;

		if (pdata)
		ts_pdata = pdata->ts;

		if (ts_pdata) {
		ts->sample_time = ts_pdata->sample_time;
		ts->mod_12b = ts_pdata->mod_12b;
		ts->ref_sel = ts_pdata->ref_sel;
		ts->adc_freq = ts_pdata->adc_freq;
		ts->ave_ctrl = ts_pdata->ave_ctrl;
		ts->touch_det_delay = ts_pdata->touch_det_delay;
		ts->settling = ts_pdata->settling;
		ts->fraction_z = ts_pdata->fraction_z;
		ts->i_drive = ts_pdata->i_drive;
		}

		INIT_DELAYED_WORK(&ts->work, stmpe_work);

		ret = request_threaded_irq(ts_irq, NULL, stmpe_ts_handler,
		IRQF_ONESHOT, STMPE_TS_NAME, ts);
		if (ret) {
		dev_err(&pdev->dev, "Failed to request IRQ %d\n", ts_irq);
		goto err_free_input;
		}

		ret = stmpe_init_hw(ts);
		if (ret)
		goto err_free_irq;

		idev->name = STMPE_TS_NAME;
		idev->id.bustype = BUS_I2C;
		idev->evbit[0] = BIT_MASK(EV_KEY) \| BIT_MASK(EV_ABS);
		idev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);

		idev->open = stmpe_ts_open;
		idev->close = stmpe_ts_close;

		input_set_drvdata(idev, ts);

		input_set_abs_params(idev, ABS_X, 0, XY_MASK, 0, 0);
		input_set_abs_params(idev, ABS_Y, 0, XY_MASK, 0, 0);
		input_set_abs_params(idev, ABS_PRESSURE, 0x0, 0xff, 0, 0);

		ret = input_register_device(idev);
		if (ret) {
		dev_err(&pdev->dev, "Could not register input device\n");
		goto err_free_irq;
		}

		return ret;

		err_free_irq:
		free_irq(ts_irq, ts);
		err_free_input:
		input_free_device(idev);
		platform_set_drvdata(pdev, NULL);
		err_free_ts:
		kfree(ts);
		err_out:
		return ret;
		}

		static int __devexit stmpe_ts_remove(struct platform_device *pdev)
		{
		struct stmpe_touch *ts = platform_get_drvdata(pdev);
		unsigned int ts_irq = platform_get_irq_byname(pdev, "FIFO_TH");

		stmpe_disable(ts->stmpe, STMPE_BLOCK_TOUCHSCREEN);

		free_irq(ts_irq, ts);

		platform_set_drvdata(pdev, NULL);

		input_unregister_device(ts->idev);
		input_free_device(ts->idev);

		kfree(ts);

		return 0;
		}

		static struct platform_driver stmpe_ts_driver = {
		.driver = {
		.name = STMPE_TS_NAME,
		.owner = THIS_MODULE,
		},
		.probe = stmpe_input_probe,
		.remove = __devexit_p(stmpe_ts_remove),
		};

		static int __init stmpe_ts_init(void)
		{
		return platform_driver_register(&stmpe_ts_driver);
		}

		module_init(stmpe_ts_init);

		static void __exit stmpe_ts_exit(void)
		{
		platform_driver_unregister(&stmpe_ts_driver);
		}

		module_exit(stmpe_ts_exit);

		MODULE_AUTHOR("Luotao Fu <l.fu@pengutronix.de>");
		MODULE_DESCRIPTION("STMPEXXX touchscreen driver");
		MODULE_LICENSE("GPL");
		MODULE_ALIAS("platform:" STMPE_TS_NAME);