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Commit 72d18a7b authored by Dan Liang's avatar Dan Liang Committed by Dmitry Torokhov
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Input: add driver for Atmel integrated touchscreen controller 



The AT91SAM9RL SoC integrates a Touchscreen Controller which
can trigger ADC conversion periodically.

Signed-off-by: default avatarJustin Waters <justin.waters@timesys.com>
Signed-off-by: default avatarDan Liang <dan.liang@atmel.com>
Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
parent 9460b652

drivers/input/touchscreen/Kconfig

+12 −0
Original line number Diff line number Diff line
@@ -205,6 +205,18 @@ config TOUCHSCREEN_TOUCHWIN 
	  To compile this driver as a module, choose M here: the

	  module will be called touchwin.



config TOUCHSCREEN_ATMEL_TSADCC

	tristate "Atmel Touchscreen Interface"

	depends on ARCH_AT91SAM9RL

	help

	  Say Y here if you have a 4-wire touchscreen connected to the

          ADC Controller on your Atmel SoC (such as the AT91SAM9RL).



	  If unsure, say N.



	  To compile this driver as a module, choose M here: the

	  module will be called atmel_tsadcc.



config TOUCHSCREEN_UCB1400

	tristate "Philips UCB1400 touchscreen"

	select AC97_BUS

drivers/input/touchscreen/Makefile

+1 −0
Original line number Diff line number Diff line
@@ -7,6 +7,7 @@ 
wm97xx-ts-y := wm97xx-core.o



obj-$(CONFIG_TOUCHSCREEN_ADS7846)	+= ads7846.o

obj-$(CONFIG_TOUCHSCREEN_ATMEL_TSADCC)	+= atmel_tsadcc.o

obj-$(CONFIG_TOUCHSCREEN_BITSY)		+= h3600_ts_input.o

obj-$(CONFIG_TOUCHSCREEN_CORGI)		+= corgi_ts.o

obj-$(CONFIG_TOUCHSCREEN_GUNZE)		+= gunze.o

drivers/input/touchscreen/atmel_tsadcc.c

0 → 100644
+332 −0
Original line number Diff line number Diff line 
/*

 *  Atmel Touch Screen Driver

 *

 *  Copyright (c) 2008 ATMEL

 *  Copyright (c) 2008 Dan Liang

 *  Copyright (c) 2008 TimeSys Corporation

 *  Copyright (c) 2008 Justin Waters

 *

 *  Based on touchscreen code from Atmel Corporation.

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License version 2 as

 *  published by the Free Software Foundation.

 */

#include <linux/init.h>

#include <linux/err.h>

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/input.h>

#include <linux/slab.h>

#include <linux/interrupt.h>

#include <linux/clk.h>

#include <linux/platform_device.h>

#include <linux/io.h>



/* Register definitions based on AT91SAM9RL64 preliminary draft datasheet */



#define ATMEL_TSADCC_CR		0x00	/* Control register */

#define   ATMEL_TSADCC_SWRST	(1 << 0)	/* Software Reset*/

#define	  ATMEL_TSADCC_START	(1 << 1)	/* Start conversion */



#define ATMEL_TSADCC_MR		0x04	/* Mode register */

#define	  ATMEL_TSADCC_TSAMOD	(3    <<  0)	/* ADC mode */

#define	    ATMEL_TSADCC_TSAMOD_ADC_ONLY_MODE	(0x0)	/* ADC Mode */

#define	    ATMEL_TSADCC_TSAMOD_TS_ONLY_MODE	(0x1)	/* Touch Screen Only Mode */

#define	  ATMEL_TSADCC_LOWRES	(1    <<  4)	/* Resolution selection */

#define	  ATMEL_TSADCC_SLEEP	(1    <<  5)	/* Sleep mode */

#define	  ATMEL_TSADCC_PENDET	(1    <<  6)	/* Pen Detect selection */

#define	  ATMEL_TSADCC_PRESCAL	(0x3f <<  8)	/* Prescalar Rate Selection */

#define	  ATMEL_TSADCC_STARTUP	(0x7f << 16)	/* Start Up time */

#define	  ATMEL_TSADCC_SHTIM	(0xf  << 24)	/* Sample & Hold time */

#define	  ATMEL_TSADCC_PENDBC	(0xf  << 28)	/* Pen Detect debouncing time */



#define ATMEL_TSADCC_TRGR	0x08	/* Trigger register */

#define	  ATMEL_TSADCC_TRGMOD	(7      <<  0)	/* Trigger mode */

#define	    ATMEL_TSADCC_TRGMOD_NONE		(0 << 0)

#define     ATMEL_TSADCC_TRGMOD_EXT_RISING	(1 << 0)

#define     ATMEL_TSADCC_TRGMOD_EXT_FALLING	(2 << 0)

#define     ATMEL_TSADCC_TRGMOD_EXT_ANY		(3 << 0)

#define     ATMEL_TSADCC_TRGMOD_PENDET		(4 << 0)

#define     ATMEL_TSADCC_TRGMOD_PERIOD		(5 << 0)

#define     ATMEL_TSADCC_TRGMOD_CONTINUOUS	(6 << 0)

#define   ATMEL_TSADCC_TRGPER	(0xffff << 16)	/* Trigger period */



#define ATMEL_TSADCC_TSR	0x0C	/* Touch Screen register */

#define	  ATMEL_TSADCC_TSFREQ	(0xf <<  0)	/* TS Frequency in Interleaved mode */

#define	  ATMEL_TSADCC_TSSHTIM	(0xf << 24)	/* Sample & Hold time */



#define ATMEL_TSADCC_CHER	0x10	/* Channel Enable register */

#define ATMEL_TSADCC_CHDR	0x14	/* Channel Disable register */

#define ATMEL_TSADCC_CHSR	0x18	/* Channel Status register */

#define	  ATMEL_TSADCC_CH(n)	(1 << (n))	/* Channel number */



#define ATMEL_TSADCC_SR		0x1C	/* Status register */

#define	  ATMEL_TSADCC_EOC(n)	(1 << ((n)+0))	/* End of conversion for channel N */

#define	  ATMEL_TSADCC_OVRE(n)	(1 << ((n)+8))	/* Overrun error for channel N */

#define	  ATMEL_TSADCC_DRDY	(1 << 16)	/* Data Ready */

#define	  ATMEL_TSADCC_GOVRE	(1 << 17)	/* General Overrun Error */

#define	  ATMEL_TSADCC_ENDRX	(1 << 18)	/* End of RX Buffer */

#define	  ATMEL_TSADCC_RXBUFF	(1 << 19)	/* TX Buffer full */

#define	  ATMEL_TSADCC_PENCNT	(1 << 20)	/* Pen contact */

#define	  ATMEL_TSADCC_NOCNT	(1 << 21)	/* No contact */



#define ATMEL_TSADCC_LCDR	0x20	/* Last Converted Data register */

#define	  ATMEL_TSADCC_DATA	(0x3ff << 0)	/* Channel data */



#define ATMEL_TSADCC_IER	0x24	/* Interrupt Enable register */

#define ATMEL_TSADCC_IDR	0x28	/* Interrupt Disable register */

#define ATMEL_TSADCC_IMR	0x2C	/* Interrupt Mask register */

#define ATMEL_TSADCC_CDR0	0x30	/* Channel Data 0 */

#define ATMEL_TSADCC_CDR1	0x34	/* Channel Data 1 */

#define ATMEL_TSADCC_CDR2	0x38	/* Channel Data 2 */

#define ATMEL_TSADCC_CDR3	0x3C	/* Channel Data 3 */

#define ATMEL_TSADCC_CDR4	0x40	/* Channel Data 4 */

#define ATMEL_TSADCC_CDR5	0x44	/* Channel Data 5 */



#define ADC_CLOCK	1000000



struct atmel_tsadcc {

	struct input_dev	*input;

	char			phys[32];

	struct clk		*clk;

	int			irq;

};



static void __iomem		*tsc_base;



#define atmel_tsadcc_read(reg)		__raw_readl(tsc_base + (reg))

#define atmel_tsadcc_write(reg, val)	__raw_writel((val), tsc_base + (reg))



static irqreturn_t atmel_tsadcc_interrupt(int irq, void *dev)

{

	struct input_dev *input_dev = ((struct atmel_tsadcc *)dev)->input;



	unsigned int absx;

	unsigned int absy;

	unsigned int status;

	unsigned int reg;



	status = atmel_tsadcc_read(ATMEL_TSADCC_SR);

	status &= atmel_tsadcc_read(ATMEL_TSADCC_IMR);



	if (status & ATMEL_TSADCC_NOCNT) {

		/* Contact lost */

		reg = atmel_tsadcc_read(ATMEL_TSADCC_MR) | ATMEL_TSADCC_PENDBC;



		atmel_tsadcc_write(ATMEL_TSADCC_MR, reg);

		atmel_tsadcc_write(ATMEL_TSADCC_TRGR, ATMEL_TSADCC_TRGMOD_NONE);

		atmel_tsadcc_write(ATMEL_TSADCC_IDR,

				   ATMEL_TSADCC_EOC(3) | ATMEL_TSADCC_NOCNT);

		atmel_tsadcc_write(ATMEL_TSADCC_IER, ATMEL_TSADCC_PENCNT);



		input_report_key(input_dev, BTN_TOUCH, 0);

		input_sync(input_dev);



	} else if (status & ATMEL_TSADCC_PENCNT) {

		/* Pen detected */

		reg = atmel_tsadcc_read(ATMEL_TSADCC_MR);

		reg &= ~ATMEL_TSADCC_PENDBC;



		atmel_tsadcc_write(ATMEL_TSADCC_IDR, ATMEL_TSADCC_PENCNT);

		atmel_tsadcc_write(ATMEL_TSADCC_MR, reg);

		atmel_tsadcc_write(ATMEL_TSADCC_IER,

				   ATMEL_TSADCC_EOC(3) | ATMEL_TSADCC_NOCNT);

		atmel_tsadcc_write(ATMEL_TSADCC_TRGR,

				   ATMEL_TSADCC_TRGMOD_PERIOD | (0x0FFF << 16));



	} else if (status & ATMEL_TSADCC_EOC(3)) {

		/* Conversion finished */



		absx = atmel_tsadcc_read(ATMEL_TSADCC_CDR3) << 10;

		absx /= atmel_tsadcc_read(ATMEL_TSADCC_CDR2);



		absy = atmel_tsadcc_read(ATMEL_TSADCC_CDR1) << 10;

		absy /= atmel_tsadcc_read(ATMEL_TSADCC_CDR0);



		input_report_abs(input_dev, ABS_X, absx);

		input_report_abs(input_dev, ABS_Y, absy);

		input_report_key(input_dev, BTN_TOUCH, 1);

		input_sync(input_dev);

	}



	return IRQ_HANDLED;

}



/*

 * The functions for inserting/removing us as a module.

 */



static int __devinit atmel_tsadcc_probe(struct platform_device *pdev)

{

	struct atmel_tsadcc	*ts_dev;

	struct input_dev	*input_dev;

	struct resource		*res;

	int		err = 0;

	unsigned int	prsc;

	unsigned int	reg;



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (!res) {

		dev_err(&pdev->dev, "no mmio resource defined.\n");

		return -ENXIO;

	}



	/* Allocate memory for device */

	ts_dev = kzalloc(sizeof(struct atmel_tsadcc), GFP_KERNEL);

	if (!ts_dev) {

		dev_err(&pdev->dev, "failed to allocate memory.\n");

		return -ENOMEM;

	}

	platform_set_drvdata(pdev, ts_dev);



	input_dev = input_allocate_device();

	if (!input_dev) {

		dev_err(&pdev->dev, "failed to allocate input device.\n");

		err = -EBUSY;

		goto err_free_mem;

	}



	ts_dev->irq = platform_get_irq(pdev, 0);

	if (ts_dev->irq < 0) {

		dev_err(&pdev->dev, "no irq ID is designated.\n");

		err = -ENODEV;

		goto err_free_dev;

	}



	if (!request_mem_region(res->start, res->end - res->start + 1,

				"atmel tsadcc regs")) {

		dev_err(&pdev->dev, "resources is unavailable.\n");

		err = -EBUSY;

		goto err_free_dev;

	}



	tsc_base = ioremap(res->start, res->end - res->start + 1);

	if (!tsc_base) {

		dev_err(&pdev->dev, "failed to map registers.\n");

		err = -ENOMEM;

		goto err_release_mem;

	}



	err = request_irq(ts_dev->irq, atmel_tsadcc_interrupt, IRQF_DISABLED,

			pdev->dev.driver->name, ts_dev);

	if (err) {

		dev_err(&pdev->dev, "failed to allocate irq.\n");

		goto err_unmap_regs;

	}



	ts_dev->clk = clk_get(&pdev->dev, "tsc_clk");

	if (IS_ERR(ts_dev->clk)) {

		dev_err(&pdev->dev, "failed to get ts_clk\n");

		err = PTR_ERR(ts_dev->clk);

		goto err_free_irq;

	}



	ts_dev->input = input_dev;



	snprintf(ts_dev->phys, sizeof(ts_dev->phys),

		 "%s/input0", pdev->dev.bus_id);



	input_dev->name = "atmel touch screen controller";

	input_dev->phys = ts_dev->phys;

	input_dev->dev.parent = &pdev->dev;



	input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);

	input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);



	input_set_abs_params(input_dev, ABS_X, 0, 0x3FF, 0, 0);

	input_set_abs_params(input_dev, ABS_Y, 0, 0x3FF, 0, 0);



	/* clk_enable() always returns 0, no need to check it */

	clk_enable(ts_dev->clk);



	prsc = clk_get_rate(ts_dev->clk);

	dev_info(&pdev->dev, "Master clock is set at: %d Hz\n", prsc);



	prsc = prsc / ADC_CLOCK / 2 - 1;



	reg = ATMEL_TSADCC_TSAMOD_TS_ONLY_MODE		|

		((0x00 << 5) & ATMEL_TSADCC_SLEEP)	|	/* Normal Mode */

		((0x01 << 6) & ATMEL_TSADCC_PENDET)	|	/* Enable Pen Detect */

		((prsc << 8) & ATMEL_TSADCC_PRESCAL)	|	/* PRESCAL */

		((0x13 << 16) & ATMEL_TSADCC_STARTUP)	|	/* STARTUP */

		((0x0F << 28) & ATMEL_TSADCC_PENDBC);		/* PENDBC */



	atmel_tsadcc_write(ATMEL_TSADCC_CR, ATMEL_TSADCC_SWRST);

	atmel_tsadcc_write(ATMEL_TSADCC_MR, reg);

	atmel_tsadcc_write(ATMEL_TSADCC_TRGR, ATMEL_TSADCC_TRGMOD_NONE);

	atmel_tsadcc_write(ATMEL_TSADCC_TSR, (0x3 << 24) & ATMEL_TSADCC_TSSHTIM);



	atmel_tsadcc_read(ATMEL_TSADCC_SR);

	atmel_tsadcc_write(ATMEL_TSADCC_IER, ATMEL_TSADCC_PENCNT);



	/* All went ok, so register to the input system */

	err = input_register_device(input_dev);

	if (err)

		goto err_fail;



	return 0;



err_fail:

	clk_disable(ts_dev->clk);

	clk_put(ts_dev->clk);

err_free_irq:

	free_irq(ts_dev->irq, ts_dev);

err_unmap_regs:

	iounmap(tsc_base);

err_release_mem:

	release_mem_region(res->start, res->end - res->start + 1);

err_free_dev:

	input_free_device(ts_dev->input);

err_free_mem:

	kfree(ts_dev);

	return err;

}



static int __devexit atmel_tsadcc_remove(struct platform_device *pdev)

{

	struct atmel_tsadcc *ts_dev = dev_get_drvdata(&pdev->dev);

	struct resource *res;



	free_irq(ts_dev->irq, ts_dev);



	input_unregister_device(ts_dev->input);



	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	iounmap(tsc_base);

	release_mem_region(res->start, res->end - res->start + 1);



	clk_disable(ts_dev->clk);

	clk_put(ts_dev->clk);



	kfree(ts_dev);



	return 0;

}



static struct platform_driver atmel_tsadcc_driver = {

	.probe		= atmel_tsadcc_probe,

	.remove		= __devexit_p(atmel_tsadcc_remove),

	.driver		= {

		.name	= "atmel_tsadcc",

	},

};



static int __init atmel_tsadcc_init(void)

{

	return platform_driver_register(&atmel_tsadcc_driver);

}



static void __exit atmel_tsadcc_exit(void)

{

	platform_driver_unregister(&atmel_tsadcc_driver);

}



module_init(atmel_tsadcc_init);

module_exit(atmel_tsadcc_exit);





MODULE_LICENSE("GPL");

MODULE_DESCRIPTION("Atmel TouchScreen Driver");

MODULE_AUTHOR("Dan Liang <dan.liang@atmel.com>");