update for xpt2046

drivers/input/touchscreen/Kconfig

@@ -42,9 +42,9 @@ config TOUCHSCREEN_AD7877
 	  To compile this driver as a module, choose M here: the
 	  module will be called ad7877.
 	  
-config TOUCHSCREEN_RK2818_SPI_XPT2046
-	tristate "RK2818 SPI XPT2046 based touchscreens"
-	depends on SPIM_RK2818 && TOUCHSCREEN_RK2818_SPI_XPT2046_CBN = n
+config TOUCHSCREEN_XPT2046_SPI
+	tristate "XPT2046 based touchscreens: XPT2046 SPI Interface"
+	depends on SPIM_RK2818 && TOUCHSCREEN_XPT2046_CBN_SPI = n
 	help
 	  Say Y here if you have a touchscreen interface using the
 	  xpt2046 controller, and your board-specific initialization
@@ -53,10 +53,10 @@ config TOUCHSCREEN_RK2818_SPI_XPT2046
 	  If unsure, say N (but it's safe to say "Y").
 
 	  To compile this driver as a module, choose M here: the
-	  module will be called rk2818_spi_xpt2046_ts.
+	  module will be called xpt2046_ts.
 	  
-config TOUCHSCREEN_RK2818_SPI_XPT2046_CBN
-	tristate "RK2818 SPI XPT2046 CALIBRATION based touchscreens"
+config TOUCHSCREEN_XPT2046_CBN_SPI
+	tristate "XPT2046 CALIBRATION based touchscreens: XPT2046 SPI Interface"
 	depends on SPIM_RK2818
 	help
 	  Say Y here if you have a touchscreen interface using the
@@ -66,7 +66,7 @@ config TOUCHSCREEN_RK2818_SPI_XPT2046_CBN
 	  If unsure, say N (but it's safe to say "Y").
 
 	  To compile this driver as a module, choose M here: the
-	  module will be called rk2818_spi_xpt2046_cbn_ts.
+	  module will be called xpt2046_cbn_ts.
 
 config TOUCHSCREEN_AD7879_I2C
 	tristate "AD7879 based touchscreens: AD7879-1 I2C Interface"

drivers/input/touchscreen/Makefile

@@ -43,5 +43,5 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE)	+= mainstone-wm97xx.o
 obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE)	+= zylonite-wm97xx.o
 obj-$(CONFIG_TOUCHSCREEN_W90X900)	+= w90p910_ts.o
 obj-$(CONFIG_TOUCHSCREEN_PCAP)		+= pcap_ts.o
-obj-$(CONFIG_TOUCHSCREEN_RK2818_SPI_XPT2046)		+= rk2818_spi_xpt2046_ts.o
-obj-$(CONFIG_TOUCHSCREEN_RK2818_SPI_XPT2046_CBN)		+= rk2818_spi_xpt2046_cbn_ts.o rk2818_calibration_ts.o rk2818_largenum_ts.o
+obj-$(CONFIG_TOUCHSCREEN_XPT2046_SPI)		+= xpt2046_ts.o
+obj-$(CONFIG_TOUCHSCREEN_XPT2046_CBN_SPI)		+= xpt2046_cbn_ts.o calibration_ts.o largenum_ts.o

drivers/input/touchscreen/xpt2046_ts.c

@@ -0,0 +1,928 @@
+/*
+ * drivers/input/touchscreen/xpt2046_ts.c - driver for rk2818 spi xpt2046 device and console
+ *
+ * Copyright (C) 2010 ROCKCHIP, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+ 
+#include <linux/hwmon.h>
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/gpio.h>
+#include <linux/spi/spi.h>
+#include <asm/irq.h>
+
+#include "xpt2046_ts.h"
+
+/*
+ * This code has been heavily tested on a Nokia 770, and lightly
+ * tested on other xpt2046 devices (OSK/Mistral, Lubbock).
+ * TSC2046 is just newer xpt2046 silicon.
+ * Support for ads7843 tested on Atmel at91sam926x-EK.
+ * Support for ads7845 has only been stubbed in.
+ *
+ * IRQ handling needs a workaround because of a shortcoming in handling
+ * edge triggered IRQs on some platforms like the OMAP1/2. These
+ * platforms don't handle the ARM lazy IRQ disabling properly, thus we
+ * have to maintain our own SW IRQ disabled status. This should be
+ * removed as soon as the affected platform's IRQ handling is fixed.
+ *
+ * app note sbaa036 talks in more detail about accurate sampling...
+ * that ought to help in situations like LCDs inducing noise (which
+ * can also be helped by using synch signals) and more generally.
+ * This driver tries to utilize the measures described in the app
+ * note. The strength of filtering can be set in the board-* specific
+ * files.
+ */
+#define XPT2046_DEBUG			0
+#if XPT2046_DEBUG
+	#define xpt2046printk(msg...)	printk(msg);
+#else
+	#define xpt2046printk(msg...)
+#endif
+#define LCD_MAX_LENGTH				800
+#define LCD_MAX_WIDTH				480
+#define PT2046_TOUCH_AD_LEFT		3855
+#define PT2046_TOUCH_AD_RIGHT		260
+#define PT2046_TOUCH_AD_TOP		300
+#define PT2046_TOUCH_AD_BOTTOM	3755
+#define AD_TO_X(adx)	(LCD_MAX_WIDTH * (adx - PT2046_TOUCH_AD_TOP) / ( PT2046_TOUCH_AD_BOTTOM  - PT2046_TOUCH_AD_TOP ))
+#define AD_TO_Y(ady)	(LCD_MAX_LENGTH * (PT2046_TOUCH_AD_LEFT - ady) / (PT2046_TOUCH_AD_LEFT - PT2046_TOUCH_AD_RIGHT))
+
+#define TS_POLL_DELAY	(15 * 1000000)	/* ns delay before the first sample */
+#define TS_POLL_PERIOD	(15 * 1000000)	/* ns delay between samples */
+
+#define DEBOUNCE_REPTIME  3
+/* this driver doesn't aim at the peak continuous sample rate */
+#define	SAMPLE_BITS	(8 /*cmd*/ + 16 /*sample*/ + 2 /* before, after */)
+
+struct ts_event {
+	/* For portability, we can't read 12 bit values using SPI (which
+	 * would make the controller deliver them as native byteorder u16
+	 * with msbs zeroed).  Instead, we read them as two 8-bit values,
+	 * *** WHICH NEED BYTESWAPPING *** and range adjustment.
+	 */
+	u16	x;
+	u16	y;
+	int	ignore;
+};
+
+/*
+ * We allocate this separately to avoid cache line sharing issues when
+ * driver is used with DMA-based SPI controllers (like atmel_spi) on
+ * systems where main memory is not DMA-coherent (most non-x86 boards).
+ */
+struct xpt2046_packet {
+	u8			read_x, read_y, pwrdown;
+	u16			dummy;		/* for the pwrdown read */
+	struct ts_event		tc;
+};
+
+struct xpt2046 {
+	struct input_dev	*input;
+	char			phys[32];
+	char			name[32];
+
+	struct spi_device	*spi;
+
+	u16			model;
+	bool			swap_xy;
+	
+	struct xpt2046_packet	*packet;
+
+	struct spi_transfer	xfer[18];
+	struct spi_message	msg[5];
+	struct spi_message	*last_msg;
+	int			msg_idx;
+	int			read_cnt;
+	int			read_rep;
+	int			last_read;
+
+	u16			debounce_max;
+	u16			debounce_tol;
+	u16			debounce_rep;
+
+	u16			penirq_recheck_delay_usecs;
+
+	spinlock_t		lock;
+	struct hrtimer		timer;
+	unsigned		pendown:1;	/* P: lock */
+	unsigned		pending:1;	/* P: lock */
+// FIXME remove "irq_disabled"
+	unsigned		irq_disabled:1;	/* P: lock */
+	unsigned		disabled:1;
+	unsigned		is_suspended:1;
+
+	int			(*filter)(void *data, int data_idx, int *val);
+	void			*filter_data;
+	void			(*filter_cleanup)(void *data);
+	int			(*get_pendown_state)(void);
+	int			gpio_pendown;
+
+	void			(*wait_for_sync)(void);
+};
+
+/* leave chip selected when we're done, for quicker re-select? */
+#if	0
+#define	CS_CHANGE(xfer)	((xfer).cs_change = 1)
+#else
+#define	CS_CHANGE(xfer)	((xfer).cs_change = 0)
+#endif
+
+/*--------------------------------------------------------------------------*/
+
+/* The xpt2046 has touchscreen and other sensors.
+ * Earlier xpt2046 chips are somewhat compatible.
+ */
+#define	XPT2046_START			(1 << 7)
+#define	XPT2046_A2A1A0_d_y		(1 << 4)	/* differential */
+#define	XPT2046_A2A1A0_d_z1		(3 << 4)	/* differential */
+#define	XPT2046_A2A1A0_d_z2		(4 << 4)	/* differential */
+#define	XPT2046_A2A1A0_d_x		(5 << 4)	/* differential */
+#define	XPT2046_A2A1A0_temp0	(0 << 4)	/* non-differential */
+#define	XPT2046_A2A1A0_vbatt	(2 << 4)	/* non-differential */
+#define	XPT2046_A2A1A0_vaux		(6 << 4)	/* non-differential */
+#define	XPT2046_A2A1A0_temp1	(7 << 4)	/* non-differential */
+#define	XPT2046_8_BIT			(1 << 3)
+#define	XPT2046_12_BIT			(0 << 3)
+#define	XPT2046_SER				(1 << 2)	/* non-differential */
+#define	XPT2046_DFR				(0 << 2)	/* differential */
+#define	XPT2046_PD10_PDOWN		(0 << 0)	/* lowpower mode + penirq */
+#define	XPT2046_PD10_ADC_ON		(1 << 0)	/* ADC on */
+#define	XPT2046_PD10_REF_ON		(2 << 0)	/* vREF on + penirq */
+#define	XPT2046_PD10_ALL_ON		(3 << 0)	/* ADC + vREF on */
+
+#define	MAX_12BIT	((1<<12)-1)
+
+/* leave ADC powered up (disables penirq) between differential samples */
+#define	READ_12BIT_DFR(x, adc, vref) (XPT2046_START | XPT2046_A2A1A0_d_ ## x \
+	| XPT2046_12_BIT | XPT2046_DFR | \
+	(adc ? XPT2046_PD10_ADC_ON : 0) | (vref ? XPT2046_PD10_REF_ON : 0))
+
+#define	READ_Y(vref)	(READ_12BIT_DFR(y,  1, vref))
+#define	READ_Z1(vref)	(READ_12BIT_DFR(z1, 1, vref))
+#define	READ_Z2(vref)	(READ_12BIT_DFR(z2, 1, vref))
+
+#define	READ_X(vref)	(READ_12BIT_DFR(x,  1, vref))
+#define	PWRDOWN		(READ_12BIT_DFR(y,  0, 0))	/* LAST */
+
+/* single-ended samples need to first power up reference voltage;
+ * we leave both ADC and VREF powered
+ */
+#define	READ_12BIT_SER(x) (XPT2046_START | XPT2046_A2A1A0_ ## x \
+	| XPT2046_12_BIT | XPT2046_SER)
+
+#define	REF_ON	(READ_12BIT_DFR(x, 1, 1))
+#define	REF_OFF	(READ_12BIT_DFR(y, 0, 0))
+
+/*--------------------------------------------------------------------------*/
+/*
+ * touchscreen sensors  use differential conversions.
+ */
+
+struct dfr_req {
+	u8			command;
+	u8			pwrdown;
+	u16			dummy;		/* for the pwrdown read */
+	__be16			sample;
+	struct spi_message	msg;
+	struct spi_transfer	xfer[4];
+};
+
+static struct xpt2046_platform_data xpt2046_info = {
+	.model			= 2046,
+	.keep_vref_on 	= 1,
+	.swap_xy		= 1,
+	.x_min			= 0,
+	.x_max			= 800,
+	.y_min			= 0,
+	.y_max			= 480,
+	.debounce_max		= 7,
+	.debounce_rep		= DEBOUNCE_REPTIME,
+	.debounce_tol		= 20,
+	.gpio_pendown		= RK2818_PIN_PE3,
+
+};
+static void xpt2046_enable(struct xpt2046 *ts);
+static void xpt2046_disable(struct xpt2046 *ts);
+
+static int device_suspended(struct device *dev)
+{
+	struct xpt2046 *ts = dev_get_drvdata(dev);
+	return ts->is_suspended || ts->disabled;
+}
+
+static int xpt2046_read12_dfr(struct device *dev, unsigned command)
+{
+	struct spi_device	*spi = to_spi_device(dev);
+	struct xpt2046		*ts = dev_get_drvdata(dev);
+	struct dfr_req		*req = kzalloc(sizeof *req, GFP_KERNEL);
+	int			status;
+
+	if (!req)
+		return -ENOMEM;
+
+	spi_message_init(&req->msg);
+
+	/* take sample */
+	req->command = (u8) command;
+	req->xfer[0].tx_buf = &req->command;
+	req->xfer[0].len = 1;
+	spi_message_add_tail(&req->xfer[0], &req->msg);
+
+	req->xfer[1].rx_buf = &req->sample;
+	req->xfer[1].len = 2;
+	spi_message_add_tail(&req->xfer[1], &req->msg);
+
+	/* converter in low power mode & enable PENIRQ */
+	req->pwrdown= PWRDOWN;
+	req->xfer[2].tx_buf = &req->pwrdown;
+	req->xfer[2].len = 1;
+	spi_message_add_tail(&req->xfer[2], &req->msg);
+
+	req->xfer[3].rx_buf = &req->dummy;
+	req->xfer[3].len = 2;
+	CS_CHANGE(req->xfer[3]);
+	spi_message_add_tail(&req->xfer[3], &req->msg);
+
+	ts->irq_disabled = 1;
+	disable_irq(spi->irq);
+	status = spi_sync(spi, &req->msg);
+	ts->irq_disabled = 0;
+	enable_irq(spi->irq);
+	
+	if (status == 0) {
+		/* on-wire is a must-ignore bit, a BE12 value, then padding */
+		status = be16_to_cpu(req->sample);
+		status = status >> 3;
+		status &= 0x0fff;
+		printk("***>%s:status=%d\n",__FUNCTION__,status);
+	}
+
+	kfree(req);
+	return status;
+}
+
+
+
+/*--------------------------------------------------------------------------*/
+
+static int get_pendown_state(struct xpt2046 *ts)
+{
+	if (ts->get_pendown_state)
+		return ts->get_pendown_state();
+
+	return !gpio_get_value(ts->gpio_pendown);
+}
+
+static void null_wait_for_sync(void)
+{
+	
+}
+
+/*
+ * PENIRQ only kicks the timer.  The timer only reissues the SPI transfer,
+ * to retrieve touchscreen status.
+ *
+ * The SPI transfer completion callback does the real work.  It reports
+ * touchscreen events and reactivates the timer (or IRQ) as appropriate.
+ */
+
+static void xpt2046_rx(void *xpt)
+{
+	struct xpt2046		*ts = xpt;
+	struct xpt2046_packet	*packet = ts->packet;
+	unsigned		Rt = 1;
+	u16			x, y;
+
+	/* xpt2046_rx_val() did in-place conversion (including byteswap) from
+	 * on-the-wire format as part of debouncing to get stable readings.
+	 */
+	x = packet->tc.x;
+	y = packet->tc.y;
+
+	xpt2046printk("***>%s:x=%d,y=%d\n",__FUNCTION__,x,y);
+
+	/* range filtering */
+	if (x == MAX_12BIT)
+		x = 0;
+
+	/* Sample found inconsistent by debouncing or pressure is beyond
+	 * the maximum. Don't report it to user space, repeat at least
+	 * once more the measurement
+	 */
+	if (packet->tc.ignore) {
+
+		xpt2046printk("***>%s:ignored=%d\n",__FUNCTION__,packet->tc.ignore);
+	
+		hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+			      HRTIMER_MODE_REL);
+		return;
+	}
+
+	/* Maybe check the pendown state before reporting. This discards
+	 * false readings when the pen is lifted.
+	 */
+	if (ts->penirq_recheck_delay_usecs) {
+		udelay(ts->penirq_recheck_delay_usecs);
+		if (!get_pendown_state(ts))
+		{
+			printk("***>%s:get_pendown_state(ts)==0,discard false reading\n",__FUNCTION__);
+			Rt = 0;
+		}
+	}
+
+	/* NOTE: We can't rely on the pressure to determine the pen down
+	 * state, even this controller has a pressure sensor.  The pressure
+	 * value can fluctuate for quite a while after lifting the pen and
+	 * in some cases may not even settle at the expected value.
+	 *
+	 * The only safe way to check for the pen up condition is in the
+	 * timer by reading the pen signal state (it's a GPIO _and_ IRQ).
+	 */
+	if (Rt) {
+		struct input_dev *input = ts->input;
+		if (!ts->pendown) {
+			input_report_key(input, BTN_TOUCH, 1);
+			ts->pendown = 1;
+			printk("***>%s:input_report_key(pen down)\n",__FUNCTION__);
+		}
+		
+		x =  AD_TO_X(x);
+		y =  AD_TO_Y(y);
+		
+		if (ts->swap_xy)
+			swap(x, y);	
+		
+		input_report_abs(input, ABS_X, x);
+		input_report_abs(input, ABS_Y, y);
+
+		input_sync(input);
+		xpt2046printk("***>%s:input_report_abs(%4d/%4d)\n",__FUNCTION__,x, y);
+	}
+
+	hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_PERIOD),
+			HRTIMER_MODE_REL);
+}
+
+static int xpt2046_debounce(void *xpt, int data_idx, int *val)
+{
+	struct xpt2046		*ts = xpt;
+	static int average_val[2];
+	
+
+	xpt2046printk("***>%s:%d,%d,%d,%d,%d,%d,%d,%d\n",__FUNCTION__,
+		data_idx,ts->last_read,
+	  ts->read_cnt,ts->debounce_max,
+		abs(ts->last_read - *val),ts->debounce_tol,
+		ts->read_rep,ts->debounce_rep);
+
+	/* discard the first sample. */
+	if(!ts->read_cnt)
+	{
+		udelay(100);
+		ts->read_cnt++;
+		return XPT2046_FILTER_REPEAT;
+	}
+
+	if (ts->read_cnt==1 || (abs(ts->last_read - *val) > ts->debounce_tol)) {
+		/* Start over collecting consistent readings. */
+		ts->read_rep = 1;
+		average_val[data_idx] = *val;
+		/* Repeat it, if this was the first read or the read
+		 * wasn't consistent enough. */
+		if (ts->read_cnt < ts->debounce_max) {
+			ts->last_read = *val;
+			ts->read_cnt++;
+			return XPT2046_FILTER_REPEAT;
+		} else {
+			/* Maximum number of debouncing reached and still
+			 * not enough number of consistent readings. Abort
+			 * the whole sample, repeat it in the next sampling
+			 * period.
+			 */
+			ts->read_cnt = 0;
+			ts->last_read = 0;
+			memset(average_val,0,sizeof(average_val));
+			xpt2046printk("***>%s:XPT2046_FILTER_IGNORE\n",__FUNCTION__);
+			return XPT2046_FILTER_IGNORE;
+		}
+	} 
+	else {
+		average_val[data_idx] += *val;
+		
+		if (++ts->read_rep >= ts->debounce_rep) {
+			/* Got a good reading for this coordinate,
+			 * go for the next one. */
+			ts->read_cnt = 0;
+			ts->read_rep = 0;
+			ts->last_read = 0;
+			*val = average_val[data_idx]/(ts->debounce_rep);
+			return XPT2046_FILTER_OK;
+		} else {
+			/* Read more values that are consistent. */
+			ts->read_cnt++;
+			
+			return XPT2046_FILTER_REPEAT;
+		}
+	}
+}
+
+static int xpt2046_no_filter(void *xpt, int data_idx, int *val)
+{
+	return XPT2046_FILTER_OK;
+}
+
+static void xpt2046_rx_val(void *xpt)
+{
+	struct xpt2046 *ts = xpt;
+	struct xpt2046_packet *packet = ts->packet;
+	struct spi_message *m;
+	struct spi_transfer *t;
+	int val;
+	int action;
+	int status;
+	
+	m = &ts->msg[ts->msg_idx];
+	t = list_entry(m->transfers.prev, struct spi_transfer, transfer_list);
+
+	/* adjust:  on-wire is a must-ignore bit, a BE12 value, then padding;
+	 * built from two 8 bit values written msb-first.
+	 */
+	val = (be16_to_cpup((__be16 *)t->rx_buf) >> 3) & 0x0fff;
+
+	xpt2046printk("***>%s:value=%d\n",__FUNCTION__,val);
+	
+	action = ts->filter(ts->filter_data, ts->msg_idx, &val);
+	switch (action) {
+	case XPT2046_FILTER_REPEAT:
+		break;
+	case XPT2046_FILTER_IGNORE:
+		packet->tc.ignore = 1;
+		/* Last message will contain xpt2046_rx() as the
+		 * completion function.
+		 */
+		m = ts->last_msg;
+		break;
+	case XPT2046_FILTER_OK:
+		*(u16 *)t->rx_buf = val;
+		packet->tc.ignore = 0;
+		m = &ts->msg[++ts->msg_idx];
+		break;
+	default:
+		BUG();
+	}
+	ts->wait_for_sync();
+	status = spi_async(ts->spi, m);
+	if (status)
+		dev_err(&ts->spi->dev, "spi_async --> %d\n",
+				status);
+}
+
+static enum hrtimer_restart xpt2046_timer(struct hrtimer *handle)
+{
+	struct xpt2046	*ts = container_of(handle, struct xpt2046, timer);
+	int		status = 0;
+	
+	spin_lock(&ts->lock);
+
+	if (unlikely(!get_pendown_state(ts) ||
+		     device_suspended(&ts->spi->dev))) {
+		if (ts->pendown) {
+			struct input_dev *input = ts->input;
+			input_report_key(input, BTN_TOUCH, 0);
+			input_sync(input);
+
+			ts->pendown = 0;
+			
+			printk("***>%s:input_report_key(The touchscreen up)\n",__FUNCTION__);
+		}
+
+		/* measurement cycle ended */
+		if (!device_suspended(&ts->spi->dev)) {
+			printk("***>%s:device_suspended==0\n",__FUNCTION__);
+			ts->irq_disabled = 0;
+			enable_irq(ts->spi->irq);
+		}
+		ts->pending = 0;
+	} else {
+		/* pen is still down, continue with the measurement */
+		xpt2046printk("***>%s:pen is still down, continue with the measurement\n",__FUNCTION__);
+		ts->msg_idx = 0;
+		ts->wait_for_sync();
+		status = spi_async(ts->spi, &ts->msg[0]);
+		if (status)
+			dev_err(&ts->spi->dev, "spi_async --> %d\n", status);
+	}
+
+	spin_unlock(&ts->lock);
+	return HRTIMER_NORESTART;
+}
+
+static irqreturn_t xpt2046_irq(int irq, void *handle)
+{
+	struct xpt2046 *ts = handle;
+	unsigned long flags;
+	
+	xpt2046printk("***>%s.....%s.....%d\n",__FILE__,__FUNCTION__,__LINE__);
+	
+	spin_lock_irqsave(&ts->lock, flags);
+
+	if (likely(get_pendown_state(ts))) {
+		if (!ts->irq_disabled) {
+			/* The ARM do_simple_IRQ() dispatcher doesn't act
+			 * like the other dispatchers:  it will report IRQs
+			 * even after they've been disabled.  We work around
+			 * that here.  (The "generic irq" framework may help...)
+			 */
+			ts->irq_disabled = 1;
+			disable_irq_nosync(ts->spi->irq);
+			ts->pending = 1;
+			hrtimer_start(&ts->timer, ktime_set(0, TS_POLL_DELAY),
+					HRTIMER_MODE_REL);
+		}
+	}
+	spin_unlock_irqrestore(&ts->lock, flags);
+
+	return IRQ_HANDLED;
+}
+
+/*--------------------------------------------------------------------------*/
+
+/* Must be called with ts->lock held */
+static void xpt2046_disable(struct xpt2046 *ts)
+{
+	if (ts->disabled)
+		return;
+
+	ts->disabled = 1;
+
+	/* are we waiting for IRQ, or polling? */
+	if (!ts->pending) {
+		ts->irq_disabled = 1;
+		disable_irq(ts->spi->irq);
+	} else {
+		/* the timer will run at least once more, and
+		 * leave everything in a clean state, IRQ disabled
+		 */
+		while (ts->pending) {
+			spin_unlock_irq(&ts->lock);
+			msleep(1);
+			spin_lock_irq(&ts->lock);
+		}
+	}
+
+	/* we know the chip's in lowpower mode since we always
+	 * leave it that way after every request
+	 */
+}
+
+/* Must be called with ts->lock held */
+static void xpt2046_enable(struct xpt2046 *ts)
+{
+	if (!ts->disabled)
+		return;
+
+	ts->disabled = 0;
+	ts->irq_disabled = 0;
+	enable_irq(ts->spi->irq);
+}
+
+static int xpt2046_suspend(struct spi_device *spi, pm_message_t message)
+{
+	struct xpt2046 *ts = dev_get_drvdata(&spi->dev);
+
+	spin_lock_irq(&ts->lock);
+
+	ts->is_suspended = 1;
+	xpt2046_disable(ts);
+
+	spin_unlock_irq(&ts->lock);
+
+	return 0;
+
+}
+
+static int xpt2046_resume(struct spi_device *spi)
+{
+	struct xpt2046 *ts = dev_get_drvdata(&spi->dev);
+
+	spin_lock_irq(&ts->lock);
+
+	ts->is_suspended = 0;
+	xpt2046_enable(ts);
+
+	spin_unlock_irq(&ts->lock);
+
+	return 0;
+}
+
+static int __devinit setup_pendown(struct spi_device *spi, struct xpt2046 *ts)
+{
+	struct xpt2046_platform_data *pdata = spi->dev.platform_data;
+	int err;
+
+	/* REVISIT when the irq can be triggered active-low, or if for some
+	 * reason the touchscreen isn't hooked up, we don't need to access
+	 * the pendown state.
+	 */
+	if (!pdata->get_pendown_state && !gpio_is_valid(pdata->gpio_pendown)) {
+		dev_err(&spi->dev, "no get_pendown_state nor gpio_pendown?\n");
+		return -EINVAL;
+	}
+
+	if (pdata->get_pendown_state) {
+		ts->get_pendown_state = pdata->get_pendown_state;
+		return 0;
+	}
+
+	err = gpio_request(pdata->gpio_pendown, "xpt2046_pendown");
+	if (err) {
+		dev_err(&spi->dev, "failed to request pendown GPIO%d\n",
+				pdata->gpio_pendown);
+		return err;
+	}
+
+	ts->gpio_pendown = pdata->gpio_pendown;
+	return 0;
+}
+
+static int __devinit xpt2046_probe(struct spi_device *spi)
+{
+	struct xpt2046			*ts;
+	struct xpt2046_packet		*packet;
+	struct input_dev		*input_dev;
+	struct xpt2046_platform_data	*pdata = spi->dev.platform_data;
+	struct spi_message		*m;
+	struct spi_transfer		*x;
+	int				vref;
+	int				err;
+	
+
+	
+	if (!spi->irq) {
+		dev_dbg(&spi->dev, "no IRQ?\n");
+		return -ENODEV;
+	}
+	else{
+		spi->irq = gpio_to_irq(spi->irq);
+		dev_dbg(&spi->dev, "no IRQ?\n");
+	}
+	
+	if (!pdata) {
+		spi->dev.platform_data = &xpt2046_info;
+		pdata = spi->dev.platform_data;
+	}
+
+	/* don't exceed max specified sample rate */
+	if (spi->max_speed_hz > (125000 * SAMPLE_BITS)) {
+		dev_dbg(&spi->dev, "f(sample) %d KHz?\n",
+				(spi->max_speed_hz/SAMPLE_BITS)/1000);
+		return -EINVAL;
+	}
+
+	/* We'd set TX wordsize 8 bits and RX wordsize to 13 bits ... except
+	 * that even if the hardware can do that, the SPI controller driver
+	 * may not.  So we stick to very-portable 8 bit words, both RX and TX.
+	 */
+	spi->bits_per_word = 8;
+	spi->mode = SPI_MODE_0;
+	err = spi_setup(spi);
+	if (err < 0)
+		return err;
+
+	ts = kzalloc(sizeof(struct xpt2046), GFP_KERNEL);
+	packet = kzalloc(sizeof(struct xpt2046_packet), GFP_KERNEL);
+	input_dev = input_allocate_device();
+	if (!ts || !packet || !input_dev) {
+		err = -ENOMEM;
+		goto err_free_mem;
+	}
+
+	dev_set_drvdata(&spi->dev, ts);
+
+	ts->packet = packet;
+	ts->spi = spi;
+	ts->input = input_dev;
+	ts->swap_xy = pdata->swap_xy;
+
+	hrtimer_init(&ts->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	ts->timer.function = xpt2046_timer;
+
+	spin_lock_init(&ts->lock);
+
+	ts->model = pdata->model ? : 2046;
+
+	if (pdata->filter != NULL) {
+		if (pdata->filter_init != NULL) {
+			err = pdata->filter_init(pdata, &ts->filter_data);
+			if (err < 0)
+				goto err_free_mem;
+		}
+		ts->filter = pdata->filter;
+		ts->filter_cleanup = pdata->filter_cleanup;
+	} else if (pdata->debounce_max) {
+		ts->debounce_max = pdata->debounce_max;
+		if (ts->debounce_max < DEBOUNCE_REPTIME)
+			ts->debounce_max = DEBOUNCE_REPTIME;
+		ts->debounce_tol = pdata->debounce_tol;
+		ts->debounce_rep = pdata->debounce_rep;
+		ts->filter = xpt2046_debounce;
+		ts->filter_data = ts;
+	} else
+		ts->filter = xpt2046_no_filter;
+
+	err = setup_pendown(spi, ts);
+	if (err)
+		goto err_cleanup_filter;
+
+	if (pdata->penirq_recheck_delay_usecs)
+		ts->penirq_recheck_delay_usecs =
+				pdata->penirq_recheck_delay_usecs;
+
+	ts->wait_for_sync = pdata->wait_for_sync ? : null_wait_for_sync;
+
+	snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(&spi->dev));
+	snprintf(ts->name, sizeof(ts->name), "XPT%d Touchscreen", ts->model);
+
+	input_dev->name = ts->name;
+	input_dev->phys = ts->phys;
+	input_dev->dev.parent = &spi->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,
+			pdata->x_min ? : 0,
+			pdata->x_max ? : MAX_12BIT,
+			0, 0);
+	input_set_abs_params(input_dev, ABS_Y,
+			pdata->y_min ? : 0,
+			pdata->y_max ? : MAX_12BIT,
+			0, 0);
+	
+	vref = pdata->keep_vref_on;
+
+	/* set up the transfers to read touchscreen state; this assumes we
+	 * use formula #2 for pressure, not #3.
+	 */
+	m = &ts->msg[0];
+	x = ts->xfer;
+
+	spi_message_init(m);
+
+	/* y- still on; turn on only y+ (and ADC) */
+	packet->read_y = READ_Y(vref);
+	x->tx_buf = &packet->read_y;
+	x->len = 1;
+	spi_message_add_tail(x, m);
+
+	x++;
+	x->rx_buf = &packet->tc.y;
+	x->len = 2;
+	spi_message_add_tail(x, m);
+
+	m->complete = xpt2046_rx_val;
+	m->context = ts;
+
+	m++;
+	spi_message_init(m);
+
+	/* turn y- off, x+ on, then leave in lowpower */
+	x++;
+	packet->read_x = READ_X(vref);
+	x->tx_buf = &packet->read_x;
+	x->len = 1;
+	spi_message_add_tail(x, m);
+
+	x++;
+	x->rx_buf = &packet->tc.x;
+	x->len = 2;
+	spi_message_add_tail(x, m);
+
+	m->complete = xpt2046_rx_val;
+	m->context = ts;
+
+	/* power down */
+	m++;
+	spi_message_init(m);
+
+	x++;
+	packet->pwrdown = PWRDOWN;
+	x->tx_buf = &packet->pwrdown;
+	x->len = 1;
+	spi_message_add_tail(x, m);
+
+	x++;
+	x->rx_buf = &packet->dummy;
+	x->len = 2;
+	CS_CHANGE(*x);
+	spi_message_add_tail(x, m);
+
+	m->complete = xpt2046_rx;
+	m->context = ts;
+
+	ts->last_msg = m;
+
+	if (request_irq(spi->irq, xpt2046_irq, IRQF_TRIGGER_FALLING,
+			spi->dev.driver->name, ts)) {
+		printk("***>%s:trying pin change workaround on irq %d\n",__FUNCTION__,spi->irq);
+		err = request_irq(spi->irq, xpt2046_irq,
+				  IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING,
+				  spi->dev.driver->name, ts);
+		if (err) {
+			dev_dbg(&spi->dev, "irq %d busy?\n", spi->irq);
+			goto err_free_gpio;
+		}
+	}
+	printk("***>%s:touchscreen irq %d\n",__FUNCTION__,spi->irq);
+	
+	/* take a first sample, leaving nPENIRQ active and vREF off; avoid
+	 * the touchscreen, in case it's not connected.
+	 */
+	xpt2046_read12_dfr(&spi->dev,READ_X(1));
+
+	err = input_register_device(input_dev);
+	if (err)
+		goto err_remove_attr_group;
+
+	return 0;
+
+ err_remove_attr_group:
+	free_irq(spi->irq, ts);
+ err_free_gpio:
+	if (ts->gpio_pendown != -1)
+		gpio_free(ts->gpio_pendown);
+ err_cleanup_filter:
+	if (ts->filter_cleanup)
+		ts->filter_cleanup(ts->filter_data);
+ err_free_mem:
+	input_free_device(input_dev);
+	kfree(packet);
+	kfree(ts);
+	return err;
+}
+
+static int __devexit xpt2046_remove(struct spi_device *spi)
+{
+	struct xpt2046		*ts = dev_get_drvdata(&spi->dev);
+
+	input_unregister_device(ts->input);
+
+	xpt2046_suspend(spi, PMSG_SUSPEND);
+
+	free_irq(ts->spi->irq, ts);
+	/* suspend left the IRQ disabled */
+	enable_irq(ts->spi->irq);
+
+	if (ts->gpio_pendown != -1)
+		gpio_free(ts->gpio_pendown);
+
+	if (ts->filter_cleanup)
+		ts->filter_cleanup(ts->filter_data);
+
+	kfree(ts->packet);
+	kfree(ts);
+
+	dev_dbg(&spi->dev, "unregistered touchscreen\n");
+	return 0;
+}
+
+static struct spi_driver xpt2046_driver = {
+	.driver = {
+		.name	= "xpt2046_ts",
+		.bus	= &spi_bus_type,
+		.owner	= THIS_MODULE,
+	},
+	.probe		= xpt2046_probe,
+	.remove		= __devexit_p(xpt2046_remove),
+	.suspend	= xpt2046_suspend,
+	.resume		= xpt2046_resume,
+};
+
+static int __init xpt2046_init(void)
+{
+	return spi_register_driver(&xpt2046_driver);
+}
+module_init(xpt2046_init);
+
+static void __exit xpt2046_exit(void)
+{
+	spi_unregister_driver(&xpt2046_driver);
+}
+module_exit(xpt2046_exit);
+
+MODULE_DESCRIPTION("rk2818 spi xpt2046 TouchScreen Driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:xpt2046");

drivers/input/touchscreen/xpt2046_ts.h

@@ -0,0 +1,54 @@
+/*
+ * drivers/input/touchscreen/xpt2046_ts.h
+ *
+ * Copyright (C) 2010 ROCKCHIP, Inc.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#ifndef __DRIVERS_TOUCHSCREEN_XPT2046_TS_H
+#define __DRIVERS_TOUCHSCREEN_XPT2046_TS_H
+enum xpt2046_filter {
+	XPT2046_FILTER_OK,
+	XPT2046_FILTER_REPEAT,
+	XPT2046_FILTER_IGNORE,
+};
+
+struct xpt2046_platform_data {
+	u16	model;			/* 2046. */
+	bool	keep_vref_on;		/* set to keep vref on for differential
+					 * measurements as well */
+	bool	swap_xy;		/* swap x and y axes */
+
+	/* If set to non-zero, after samples are taken this delay is applied
+	 * and penirq is rechecked, to help avoid false events.  This value
+	 * is affected by the material used to build the touch layer.
+	 */
+	u16	penirq_recheck_delay_usecs;
+
+	u16	x_min, x_max;
+	u16	y_min, y_max;
+
+	u16	debounce_max;		/* max number of additional readings
+					 * per sample */
+	u16	debounce_tol;		/* tolerance used for filtering */
+	u16	debounce_rep;		/* additional consecutive good readings
+					 * required after the first two */
+	int	gpio_pendown;		/* the GPIO used to decide the pendown
+					 * state if get_pendown_state == NULL
+					 */
+	int	(*get_pendown_state)(void);
+	int	(*filter_init)	(struct xpt2046_platform_data *pdata,
+				 void **filter_data);
+	int	(*filter)	(void *filter_data, int data_idx, int *val);
+	void	(*filter_cleanup)(void *filter_data);
+	void	(*wait_for_sync)(void);
+};
+#endif