@@ -498,4 +498,13 @@ config TOUCHSCREEN_W90X900
To compile this driver as a module, choose M here: the
module will be called w90p910_ts.
+config TOUCHSCREEN_MRSTOUCH
+ tristate "Intel Moorestown Resistive touchscreen"
+ depends on LANGWELL_IPC && SPI_MRST
+ default y
+ help
+ Say Y here if you have a Intel Moorstown platform
+
+ To compile this driver as a module, choose M here: the
+ module will be called mrstouch.
endif
@@ -40,3 +40,4 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_ATMEL) += atmel-wm97xx.o
obj-$(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_MRSTOUCH) += mrstouch.o
new file mode 100644
@@ -0,0 +1,896 @@
+/*
+ * mrstouch.c - Intel Moorestown Resistive Touch Screen Driver
+ *
+ * Copyright (C) 2008 Intel Corp
+ *
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ *
+ * 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; version 2 of the License.
+ *
+ * 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; ifnot, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
+ *
+ * Questions/Comments/Bug fixes to Sreedhara (sreedhara.ds@intel.com)
+ * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ */
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/param.h>
+#include <linux/spi/spi.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/kthread.h>
+#include <asm/mrst_ipcdefs.h>
+
+MODULE_AUTHOR("Sreedhara Murthy. D.S, sreedhara.ds@intel.com");
+MODULE_DESCRIPTION("Intel Moorestown Resistive Touch Screen Driver");
+MODULE_LICENSE("GPL");
+
+/* PMIC Interrupt registers */
+#define PMIC_REG_ID1 0x00 /*PMIC ID1 register */
+
+/* PMIC Interrupt registers */
+#define PMIC_REG_INT 0x04 /*PMIC interrupt register */
+#define PMIC_REG_MINT 0x05 /*PMIC interrupt mask register */
+
+/* ADC Interrupt registers */
+#define PMIC_REG_ADCINT 0x5F /*ADC interrupt register */
+#define PMIC_REG_MADCINT 0x60 /*ADC interrupt mask register */
+
+/* ADC Control registers */
+#define PMIC_REG_ADCCNTL1 0x61 /*ADC control register */
+
+/* ADC Channel Selection registers */
+#define PMICADDR0 0xA4
+#define END_OF_CHANNEL 0x1F
+
+/* ADC Result register */
+#define PMIC_REG_ADCSNS0H 0x64
+
+/* ADC channels for touch screen */
+#define MRST_TS_CHAN10 0xA /* Touch screen X+ connection */
+#define MRST_TS_CHAN11 0xB /* Touch screen X- connection */
+#define MRST_TS_CHAN12 0xC /* Touch screen Y+ connection */
+#define MRST_TS_CHAN13 0xD /* Touch screen Y- connection */
+
+/* Touch screen coordinate constants */
+#define TOUCH_PRESSURE 5
+#define TOUCH_PRESSURE_FS 100
+
+#define XMOVE_LIMIT 5
+#define YMOVE_LIMIT 5
+#define XYMOVE_CNT 3
+
+#define MAX_10BIT ((1<<10)-1)
+
+/* Touch screen channel BIAS constants */
+#define XBIAS 0x20
+#define YBIAS 0x40
+#define ZBIAS 0x80
+
+/* Touch screen coordinates */
+#define MIN_X 10
+#define MAX_X 1024
+#define MIN_Y 10
+#define MAX_Y 1024
+#define WAIT_ADC_COMPLETION 10
+
+/* PMIC ADC round robin delays */
+#define ADC_LOOP_DELAY0 0x0 /* Continuous loop */
+#define ADC_LOOP_DELAY1 0x1 /* 4.5 ms approximate */
+
+/* PMIC Vendor Identifiers */
+#define PMIC_VENDOR_FS 0 /* PMIC vendor FreeScale */
+#define PMIC_VENDOR_MAXIM 1 /* PMIC vendor MAXIM */
+#define PMIC_VENDOR_NEC 2 /* PMIC vendor NEC */
+#define MRSTOUCH_MAX_CHANNELS 32 /* Maximum ADC channels */
+
+/* Touch screen device structure */
+struct mrstouch_dev {
+ struct spi_device *spi; /* SPI device associated with touch screen */
+ struct input_dev *input; /* input device for touchscreen*/
+ char phys[32]; /* Device name */
+ struct task_struct *pendet_thrd; /* PENDET interrupt handler */
+ struct semaphore lock; /* Sync between interrupt and PENDET handler */
+ bool busy; /* Busy flag */
+ u16 asr; /* Address selection register */
+ int irq; /* Touch screen IRQ # */
+ uint vendor; /* PMIC vendor */
+ uint rev; /* PMIC revision */
+ u16 x; /* X coordinate */
+ u16 y; /* Y coordinate */
+ bool pendown; /* PEN position */
+ uint xmc; /* Xmove count */
+ uint ymc; /* Xmove count */
+} ;
+
+
+/* Global Pointer to Touch screen device */
+static struct mrstouch_dev *mrstouchdevp;
+
+/* Utility to read PMIC ID */
+static int mrstouch_pmic_id(uint *vendor, uint *rev)
+{
+ int err;
+ struct mrst_pmic_reg_data adc_data;
+
+ adc_data.ioc = 1;
+ adc_data.num_entries = 1;
+ adc_data.pmic_reg_data[0].register_address = PMIC_REG_ID1;
+
+ err = mrst_pmic_ioread(&adc_data);
+ if (err)
+ return -1;
+
+ *vendor = (adc_data.pmic_reg_data[0].value) & 0x7;
+ *rev = (adc_data.pmic_reg_data[0].value >> 3) & 0x7;
+
+ return 0;
+}
+
+/*
+ * Parse ADC channels to find end of the channel configured by other ADC user
+ * NEC and MAXIM requires 4 channels and FreeScale needs 18 channels
+ */
+static int mrstouch_chan_parse(struct mrstouch_dev *tsdev)
+{
+ int err, i, j, chan, found;
+ struct mrst_pmic_reg_data pdata;
+
+ pdata.ioc = 1;
+
+ found = -1;
+ pdata.num_entries = 4;
+
+ for (i = 0; i < MRSTOUCH_MAX_CHANNELS; i++) {
+ if (found >= 0)
+ break;
+
+ for (j = 0; j <= 3; j++)
+ pdata.pmic_reg_data[j].register_address = PMICADDR0+i;
+
+ err = mrst_pmic_ioread(&pdata);
+ if (err)
+ return -1;
+
+ for (j = 0; j < pdata.num_entries; j++) {
+ chan = pdata.pmic_reg_data[j].value;
+ if (chan == END_OF_CHANNEL) {
+ found = i;
+ break;
+ }
+ }
+ }
+
+ if (found < 0)
+ return 0;
+
+ if (tsdev->vendor == PMIC_VENDOR_FS) {
+ if (found && found > (MRSTOUCH_MAX_CHANNELS - 18))
+ return -1;
+ } else {
+ if (found && found > (MRSTOUCH_MAX_CHANNELS - 4))
+ return -1;
+ }
+ return found;
+}
+
+/* Utility to enable/disable pendet.
+ * pendet set to true enables PENDET interrupt
+ * pendet set to false disables PENDET interrupt
+ * Also clears RND mask bit
+*/
+static void pendet_enable(bool pendet)
+{
+ u8 adccntrl1 = 0;
+ u8 pendet_enabled = 0;
+ int retry = 0;
+ struct mrst_pmic_reg_data adc_data;
+
+ adc_data.ioc = 1;
+
+ adc_data.num_entries = 1;
+ adc_data.pmic_reg_data[0].register_address = PMIC_REG_ADCCNTL1;
+ mrst_pmic_ioread(&adc_data);
+ adccntrl1 = adc_data.pmic_reg_data[0].value;
+
+ if (pendet)
+ adccntrl1 |= 0x20; /* Enable pendet */
+ else
+ adccntrl1 &= 0xDF; /* Disable pendet */
+
+ adc_data.num_entries = 2;
+ adc_data.pmic_reg_data[0].register_address = PMIC_REG_MADCINT;
+ adc_data.pmic_reg_data[0].value = 0x0;
+ adc_data.pmic_reg_data[1].register_address = PMIC_REG_ADCCNTL1;
+ adc_data.pmic_reg_data[1].value = adccntrl1;
+ mrst_pmic_iowrite(&adc_data);
+
+ if (!pendet)
+ return;
+
+
+ /*
+ * Sometimes even after mrst_pmic_iowrite success
+ * the PMIC register value is not updated. Retry few iterations
+ * to enable pendet.
+ */
+ adc_data.num_entries = 1;
+ adc_data.pmic_reg_data[0].register_address = PMIC_REG_ADCCNTL1;
+ mrst_pmic_ioread(&adc_data);
+ pendet_enabled = (adc_data.pmic_reg_data[0].value >> 5) & 0x01;
+
+ retry = 0;
+ while (!pendet_enabled) {
+ retry++;
+ msleep(10);
+ adc_data.pmic_reg_data[0].register_address = PMIC_REG_ADCCNTL1;
+ adc_data.pmic_reg_data[0].value = adccntrl1;
+ mrst_pmic_iowrite(&adc_data);
+
+ adc_data.pmic_reg_data[0].register_address = PMIC_REG_ADCCNTL1;
+ mrst_pmic_ioread(&adc_data);
+ pendet_enabled = (adc_data.pmic_reg_data[0].value >> 5) & 0x01;
+ if (retry >= 10) {
+ printk(KERN_ERR "Touch screen disabled\n");
+ break;
+ }
+ }
+}
+
+
+/* To read PMIC ADC touch screen result
+ * Reads ADC storage registers for higher 7 and lower 3 bits
+ * converts the two readings to single value and turns off gain bit
+ */
+static int mrstouch_ts_chan_read(u16 offset, u16 chan, u16 *vp, u16 *vm)
+{
+ int err, count;
+ u16 result;
+ struct mrst_pmic_reg_data adc_data;
+
+ adc_data.ioc = 1;
+ adc_data.num_entries = 4;
+
+ result = PMIC_REG_ADCSNS0H + offset;
+
+ if (chan == MRST_TS_CHAN12)
+ result += 4;
+
+ for (count = 0; count <= 3; count++)
+ adc_data.pmic_reg_data[count].register_address = result++;
+
+ err = mrst_pmic_ioread(&adc_data);
+ if (err)
+ return -1;
+
+ *vp = adc_data.pmic_reg_data[0].value << 3; /* Higher 7 bits */
+ *vp |= adc_data.pmic_reg_data[1].value & 0x7; /* Lower 3 bits */
+ *vp &= 0x3FF;
+
+ *vm = adc_data.pmic_reg_data[2].value << 3; /* Higher 7 bits */
+ *vm |= adc_data.pmic_reg_data[3].value & 0x7; /* Lower 3 bits */
+ *vm &= 0x3FF;
+
+ return 0;
+}
+
+/* To configure touch screen channels
+ * Writes touch screen channels to ADC address selection registers
+ */
+static int mrstouch_ts_chan_set(uint offset)
+{
+ int err, count;
+ u16 chan;
+ struct mrst_pmic_reg_data adc_data;
+
+ adc_data.ioc = 1;
+ adc_data.num_entries = 5;
+
+ chan = PMICADDR0 + offset;
+ for (count = 0; count <= 3; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = MRST_TS_CHAN10 + count;
+ }
+ adc_data.pmic_reg_data[count].register_address = chan;
+ adc_data.pmic_reg_data[count].value = END_OF_CHANNEL;
+
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ return -1;
+
+ return 0;
+}
+
+/* Initialize ADC */
+static int mrstouch_adc_init(struct mrstouch_dev *tsdev)
+{
+ int err, start;
+ struct mrst_pmic_mod_reg_data adc_data;
+
+ err = mrstouch_pmic_id(&tsdev->vendor, &tsdev->rev);
+ if (err) {
+ printk(KERN_ERR "Error in reading PMIC Id");
+ return err;
+ }
+
+ start = mrstouch_chan_parse(tsdev);
+ if (start == -1) {
+ printk(KERN_ERR "Error in parse channels");
+ return start;
+ }
+
+ tsdev->asr = start;
+
+ /* ADC power on, start, enable PENDET and set loop delay
+ * ADC loop delay is set to 4.5 ms approximately
+ * Loop delay more than this results in jitter in adc readings
+ * Setting loop delay to 0 (continous loop) in MAXIM stops PENDET
+ * interrupt generation sometimes.
+ */
+ adc_data.ioc = 1;
+ adc_data.num_entries = 2;
+ adc_data.pmic_mod_reg_data[0].register_address = PMIC_REG_ADCCNTL1;
+ adc_data.pmic_mod_reg_data[0].bit_map = 0xE7;
+
+ adc_data.pmic_mod_reg_data[1].register_address = PMIC_REG_MADCINT;
+ adc_data.pmic_mod_reg_data[1].bit_map = 0x03;
+
+ if (tsdev->vendor == PMIC_VENDOR_FS) {
+ adc_data.pmic_mod_reg_data[0].value = 0xE0 | ADC_LOOP_DELAY0;
+ adc_data.pmic_mod_reg_data[1].value = 0x5;
+ } else {
+ /* NEC and MAXIm not consistent with loop delay 0 */
+ adc_data.pmic_mod_reg_data[0].value = 0xE0 | ADC_LOOP_DELAY1;
+ adc_data.pmic_mod_reg_data[1].value = 0x0;
+
+ /* configure touch screen channels */
+ err = mrstouch_ts_chan_set(tsdev->asr);
+ if (err)
+ return err;
+ }
+
+ err = mrst_pmic_ioread_modify(&adc_data);
+
+ return err;
+}
+
+/* Reports x,y coordinates to event subsystem */
+static void mrstouch_report_xy(struct mrstouch_dev *tsdev, u16 x, u16 y, u16 z)
+{
+ int xdiff, ydiff;
+ bool moving = false;
+
+ if (tsdev->pendown && z <= TOUCH_PRESSURE) {
+ /* Pen removed, report button release */
+ dev_dbg(&tsdev->spi->dev, "BTN REL(%d)", z);
+ input_report_key(tsdev->input, BTN_TOUCH, 0);
+ tsdev->pendown = false;
+
+ tsdev->xmc = 0;
+ tsdev->ymc = 0;
+ return;
+ }
+
+ xdiff = abs(x - tsdev->x);
+ ydiff = abs(y - tsdev->y);
+
+ if (xdiff > XMOVE_LIMIT)
+ tsdev->xmc++; /* Increment X move count */
+ if (ydiff > YMOVE_LIMIT)
+ tsdev->ymc++; /* Increment Y move count */
+
+ /*
+ if x and y values changes for XYMOVE_CNT readings it is considered
+ as stylus is moving. This is required to differentiate between stylus
+ movement and jitter
+ */
+ if (tsdev->xmc > XYMOVE_CNT || tsdev->ymc > XYMOVE_CNT)
+ moving = true; /* Stylus is moving */
+
+ if (x < MIN_X || x > MAX_X || y < MIN_Y || y > MAX_Y) {
+ /* Spurious values, release button if touched and return */
+ if (tsdev->pendown) {
+ dev_dbg(&tsdev->spi->dev, "BTN REL(%d)", z);
+ input_report_key(tsdev->input, BTN_TOUCH, 0);
+ tsdev->pendown = false;
+ tsdev->xmc = 0;
+ tsdev->ymc = 0;
+ }
+ return;
+ } else if (!moving && (xdiff <= XMOVE_LIMIT || ydiff <= YMOVE_LIMIT))
+ /*
+ ADC readings are differ by small variations in alternate
+ readings. Multiple ADC readings and averaging results in
+ slow response. All ADC readings fall within move limit are
+ considered as value of previous reading. This minimizes small
+ observable jitter in mouse pointer when stylus at fixed position
+ */
+ return;
+ else {
+ /* save x and y values */
+ tsdev->x = x;
+ tsdev->y = y;
+ }
+
+ input_report_abs(tsdev->input, ABS_X, x);
+ input_report_abs(tsdev->input, ABS_Y, y);
+ input_sync(tsdev->input);
+
+ if (!tsdev->pendown && z > TOUCH_PRESSURE) {
+ /* Pen touched, report button touch */
+ dev_dbg(&tsdev->spi->dev, "BTN TCH(%d, %d, %d)", x, y, z);
+ input_report_key(tsdev->input, BTN_TOUCH, 1);
+ tsdev->pendown = true;
+ }
+}
+
+
+/* Utility to start ADC, used by freescale handler */
+static int pendet_mask(uint mask)
+{
+ int err = 0;
+ struct mrst_pmic_mod_reg_data adc_data;
+
+ adc_data.ioc = 1;
+ adc_data.num_entries = 1;
+ adc_data.pmic_mod_reg_data[1].register_address = PMIC_REG_MADCINT;
+ adc_data.pmic_mod_reg_data[1].bit_map = 0x02;
+ adc_data.pmic_mod_reg_data[1].value = mask;
+
+ err = mrst_pmic_ioread_modify(&adc_data);
+
+ return err;
+}
+
+/* Utility to read ADC, used by freescale handler */
+static int mrstouch_pmic_fs_adc_read(struct mrstouch_dev *tsdev)
+{
+ int err;
+ u16 x, y, z, result;
+ struct mrst_pmic_reg_data adc_data;
+
+ result = PMIC_REG_ADCSNS0H + tsdev->asr;
+
+ adc_data.ioc = 1;
+ adc_data.num_entries = 4;
+ adc_data.pmic_reg_data[0].register_address = result + 4;
+ adc_data.pmic_reg_data[1].register_address = result + 5;
+ adc_data.pmic_reg_data[2].register_address = result + 16;
+ adc_data.pmic_reg_data[3].register_address = result + 17;
+
+ err = mrst_pmic_ioread(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ x = adc_data.pmic_reg_data[0].value << 3; /* Higher 7 bits */
+ x |= adc_data.pmic_reg_data[1].value & 0x7; /* Lower 3 bits */
+ x &= 0x3FF;
+
+ y = adc_data.pmic_reg_data[2].value << 3; /* Higher 7 bits */
+ y |= adc_data.pmic_reg_data[3].value & 0x7; /* Lower 3 bits */
+ y &= 0x3FF;
+
+ /* Read Z value */
+ adc_data.num_entries = 2;
+ adc_data.pmic_reg_data[0].register_address = result + 28;
+ adc_data.pmic_reg_data[1].register_address = result + 29;
+
+ err = mrst_pmic_ioread(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ z = adc_data.pmic_reg_data[0].value << 3; /* Higher 7 bits */
+ z |= adc_data.pmic_reg_data[1].value & 0x7; /* Lower 3 bits */
+ z &= 0x3FF;
+
+ dev_dbg(&tsdev->spi->dev, "X: %d, Y: %d, Z: %d", x, y, z);
+
+ if (z >= TOUCH_PRESSURE_FS) { /* Pen Removed */
+ mrstouch_report_xy(tsdev, x, y, TOUCH_PRESSURE - 1);
+ return TOUCH_PRESSURE - 1;
+ } else { /* Pen Touched */
+ mrstouch_report_xy(tsdev, x, y, TOUCH_PRESSURE + 1);
+ return TOUCH_PRESSURE + 1;
+ }
+
+ return 0;
+
+ipc_error:
+ printk(KERN_ERR "IPC Error: %s", __func__);
+ return -1;
+}
+
+/* To handle free scale pmic pendet interrupt */
+static int pmic0_pendet(void *data)
+{
+ int err, count;
+ u16 chan;
+ unsigned int touched;
+ struct mrst_pmic_reg_data adc_data;
+ struct mrstouch_dev *tsdev = (struct mrstouch_dev *)data;
+
+ chan = PMICADDR0 + tsdev->asr;
+
+ adc_data.ioc = 1;
+ /* Set X BIAS */
+ adc_data.num_entries = 5;
+ for (count = 0; count <= 3; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = 0x2A;
+ }
+ adc_data.pmic_reg_data[count].register_address = chan++; /* Dummy */
+ adc_data.pmic_reg_data[count].value = 0;
+
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ msleep(WAIT_ADC_COMPLETION);
+
+ /* Set Y BIAS */
+ adc_data.num_entries = 5;
+ for (count = 0; count <= 3; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = 0x4A;
+ }
+ adc_data.pmic_reg_data[count].register_address = chan++; /* Dummy */
+ adc_data.pmic_reg_data[count].value = 0;
+
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ msleep(WAIT_ADC_COMPLETION);
+
+ /* Set Z BIAS */
+ chan += 2;
+ adc_data.num_entries = 4;
+ for (count = 0; count <= 3; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = 0x8A;
+ }
+
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ msleep(WAIT_ADC_COMPLETION);
+
+ /*Read touch screen channels till pen removed
+ * Freescale reports constant value of z for all points
+ * z is high when screen is not touched and low when touched
+ * Map high z value to not touched and low z value to pen touched
+ */
+ touched = mrstouch_pmic_fs_adc_read(tsdev);
+ while (touched > TOUCH_PRESSURE) {
+ touched = mrstouch_pmic_fs_adc_read(tsdev);
+ msleep(WAIT_ADC_COMPLETION);
+ }
+
+ /* Clear all TS channels */
+ chan = PMICADDR0 + tsdev->asr;
+ adc_data.ioc = 1;
+ adc_data.num_entries = 5;
+ for (count = 0; count <= 4; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = 0x0;
+ }
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ for (count = 0; count <= 4; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = 0x0;
+ }
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ chan += 2;
+ for (count = 0; count <= 4; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = 0x0;
+ }
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ goto ipc_error;
+
+ return 0;
+
+ipc_error:
+ printk(KERN_ERR "IPC Error: %s", __func__);
+ return -1;
+}
+
+
+/* To enable X, Y and Z bias values
+ * Enables YPYM for X channels and XPXM for Y channels
+ */
+static int mrstouch_ts_bias_set(uint offset, uint bias)
+{
+ int err, count;
+ u16 chan, start;
+ struct mrst_pmic_reg_data adc_data;
+
+ chan = PMICADDR0 + offset;
+ start = MRST_TS_CHAN10;
+
+ adc_data.ioc = 1;
+ adc_data.num_entries = 4;
+
+ for (count = 0; count <= 3; count++) {
+ adc_data.pmic_reg_data[count].register_address = chan++;
+ adc_data.pmic_reg_data[count].value = bias | (start + count);
+ }
+
+ err = mrst_pmic_iowrite(&adc_data);
+ if (err)
+ return -1;
+
+ return 0;
+}
+
+/* To read touch screen channel values */
+static int mrstouch_adc_read(struct mrstouch_dev *tsdev)
+{
+ int err;
+ u16 xp, xm, yp, ym, zp, zm;
+
+ /* configure Y bias for X channels */
+ err = mrstouch_ts_bias_set(tsdev->asr, YBIAS);
+ if (err)
+ goto ipc_error;
+
+ msleep(WAIT_ADC_COMPLETION);
+
+ /* read x+ and x- channels */
+ err = mrstouch_ts_chan_read(tsdev->asr, MRST_TS_CHAN10, &xp, &xm);
+ if (err)
+ goto ipc_error;
+
+ /* configure x bias for y channels */
+ err = mrstouch_ts_bias_set(tsdev->asr, XBIAS);
+ if (err)
+ goto ipc_error;
+
+ msleep(WAIT_ADC_COMPLETION);
+
+ /* read y+ and y- channels */
+ err = mrstouch_ts_chan_read(tsdev->asr, MRST_TS_CHAN12, &yp, &ym);
+ if (err)
+ goto ipc_error;
+
+ /* configure z bias for x and y channels */
+ err = mrstouch_ts_bias_set(tsdev->asr, ZBIAS);
+ if (err)
+ goto ipc_error;
+
+ msleep(WAIT_ADC_COMPLETION);
+
+ /* read z+ and z- channels */
+ err = mrstouch_ts_chan_read(tsdev->asr, MRST_TS_CHAN10, &zp, &zm);
+ if (err)
+ goto ipc_error;
+
+#if defined(MRSTOUCH_PRINT_XYZP)
+ printk(KERN_INFO "X+: %d, Y+: %d, Z+: %d\n", xp, yp, zp);
+#endif
+
+#if defined(MRSTOUCH_PRINT_XYZP)
+ printk(KERN_INFO "X-: %d, Y-: %d, Z-: %d\n", xm, ym, zm);
+#endif
+ if (xm < MIN_X || xm > MAX_X || ym < MIN_Y || ym > MAX_Y)
+ return TOUCH_PRESSURE - 1;
+
+ mrstouch_report_xy(tsdev, xp, yp, zp); /* report x and y to eventX */
+
+ return zp;
+
+ipc_error:
+ printk(KERN_ERR "IPC Error: %s", __func__);
+ return -1;
+}
+
+/* PENDET interrupt handler function for NEC and MAXIM */
+static void pmic12_pendet(void *data)
+{
+ unsigned int touched;
+ struct mrstouch_dev *tsdev = (struct mrstouch_dev *)data;
+
+ /* read touch screen channels till pen removed */
+ touched = mrstouch_adc_read(tsdev);
+ while (touched > TOUCH_PRESSURE) {
+ touched = mrstouch_adc_read(tsdev);
+ msleep(WAIT_ADC_COMPLETION);
+ }
+}
+
+/* Handler to process PENDET interrupt */
+int mrstouch_pendet(void *data)
+{
+ struct mrstouch_dev *tsdev = (struct mrstouch_dev *)data;
+
+ while (1) {
+ down(&tsdev->lock); /* Wait for PENDET interrupt */
+
+ if (tsdev->busy)
+ return 0;
+
+ tsdev->busy = true;
+
+ if (tsdev->vendor == PMIC_VENDOR_NEC ||
+ tsdev->vendor == PMIC_VENDOR_MAXIM) {
+ /* PENDET must be disabled in NEC before reading ADC */
+ pendet_enable(false); /* Disbale PENDET */
+ pmic12_pendet(tsdev);
+ pendet_enable(true); /*Enable PENDET */
+ } else if (tsdev->vendor == PMIC_VENDOR_FS) {
+ pendet_mask(0); /* Disable PENDET */
+ pmic0_pendet(tsdev);
+ pendet_mask(1); /* Enable PENDET */
+ } else
+ printk(KERN_ERR "Unknown PMIC, Not supported\n");
+
+ tsdev->busy = false;
+ }
+
+ return 0;
+}
+
+/* PENDET interrupt handler */
+static irqreturn_t pendet_intr_handler(int irq, void *handle)
+{
+ struct mrstouch_dev *tsdev = (struct mrstouch_dev *)handle;
+ up(&tsdev->lock);
+
+ return IRQ_HANDLED;
+}
+
+/* Intializes input device and registers with input subsystem */
+static int ts_input_dev_init(struct mrstouch_dev *tsdev, struct spi_device *spi)
+{
+ int err = 0;
+
+ tsdev->input = input_allocate_device();
+ if (!tsdev->input) {
+ dev_err(&tsdev->spi->dev, "%s", "Input dev allocation failed");
+ return -ENOMEM;
+ }
+
+ tsdev->input->name = "mrst_touchscreen";
+ snprintf(tsdev->phys, sizeof(tsdev->phys),
+ "%s/input0", dev_name(&spi->dev));
+ tsdev->input->phys = tsdev->phys;
+ tsdev->input->dev.parent = &spi->dev;
+
+ tsdev->input->id.vendor = tsdev->vendor;
+ tsdev->input->id.version = tsdev->rev;
+
+ tsdev->input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
+ tsdev->input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
+
+ input_set_abs_params(tsdev->input, ABS_X, MIN_X, MIN_Y, 0, 0);
+ input_set_abs_params(tsdev->input, ABS_Y, MIN_X, MIN_Y, 0, 0);
+
+ err = input_register_device(tsdev->input);
+ if (err) {
+ dev_err(&tsdev->spi->dev, "%s", "Input dev register failed");
+ input_free_device(tsdev->input);
+ return err;
+ }
+
+ dev_dbg(&tsdev->spi->dev, "%s", "mrstouch initialized");
+
+ return 0;
+
+}
+
+/* Probe function for touch screen driver */
+static int __devinit mrstouch_probe(struct spi_device *mrstouch_spi)
+{
+ int err;
+ unsigned int myirq;
+ struct mrstouch_dev *tsdev;
+
+ myirq = mrstouch_spi->irq;
+
+ if (!mrstouch_spi->irq) {
+ dev_err(&mrstouch_spi->dev, "%s(%d)", "No IRQ", myirq);
+ return -EINVAL;
+ }
+
+ tsdev = kzalloc(sizeof(struct mrstouch_dev), GFP_KERNEL);
+ if (!tsdev) {
+ dev_err(&tsdev->spi->dev, "%s", "ERROR: Memory failure");
+ return -ENOMEM;
+ }
+
+ tsdev->irq = myirq;
+
+ err = ts_input_dev_init(tsdev, mrstouch_spi);
+ if (err) {
+ dev_err(&tsdev->spi->dev, "%s", "ts_input_dev_init failed");
+ kfree(tsdev);
+ return err;
+ }
+
+ err = mrstouch_adc_init(tsdev);
+ if (err) {
+ dev_err(&tsdev->spi->dev, "%s", "ADC init failed");
+ goto mrstouch_error;
+ }
+
+ dev_set_drvdata(&mrstouch_spi->dev, tsdev);
+ tsdev->spi = mrstouch_spi;
+
+ sema_init(&tsdev->lock, 1);
+ down(&tsdev->lock);
+
+ tsdev->pendet_thrd = kthread_run(mrstouch_pendet,
+ (void *)tsdev, "pendet handler");
+ if (IS_ERR(tsdev->pendet_thrd)) {
+ dev_err(&tsdev->spi->dev, "kthread_run failed \n");
+ goto mrstouch_error;
+ }
+
+ dev_dbg(&tsdev->spi->dev, "Requesting IRQ-%d", myirq);
+ err = request_irq(myirq, pendet_intr_handler,
+ 0, "mrstouch", tsdev);
+ if (err) {
+ dev_err(&tsdev->spi->dev, "IRQ Request Failed - %d", err);
+ goto mrstouch_error;
+ }
+
+ dev_dbg(&tsdev->spi->dev, "%s", "Driver initialized");
+
+ return 0;
+
+ mrstouch_error:
+ input_unregister_device(tsdev->input);
+ kfree(tsdev);
+ return -1;
+}
+
+static __devexit int mrstouch_remove(struct spi_device *spi)
+{
+ free_irq(mrstouchdevp->irq, mrstouchdevp);
+ input_unregister_device(mrstouchdevp->input);
+ kfree(mrstouchdevp);
+ return 0;
+}
+
+static struct spi_driver mrstouch_driver = {
+ .driver = {
+ .name = "pmic_touch",
+ .bus = &spi_bus_type,
+ .owner = THIS_MODULE,
+ },
+ .probe = mrstouch_probe,
+ .remove = __devexit_p(mrstouch_remove),
+};
+
+static int __init mrstouch_module_init(void)
+{
+ return spi_register_driver(&mrstouch_driver);
+}
+
+static void __exit mrstouch_module_exit(void)
+{
+ spi_unregister_driver(&mrstouch_driver);
+}
+
+module_init(mrstouch_module_init);
+module_exit(mrstouch_module_exit);
Hello, Resubmitting the patch. Changes include comments from Dmitry Torokhov [dmitry.torokhov@gmail.com] Summary of changes: 1. Kill this default line. => Corrected 2. To compile this driver as a module... => Corrected 3. dev_dbg()?, dev_err()? => Local debug print utility is replaced by dev_dbg and dev_err 4. Unused variables removed from struct mrstouch_dev 5. Why global? Can't we write our drivers so they support multiple devices even though platform may only have one? =>Global static struct mrstouch_dev *mrstouchdevp removed and corrected as per the suggestion to support multiple devices 6. input_sync(); not required after reporting button action events. input_sync() is enough after reporting X,Y values 7. -ENOMEM, -EINVAL used as per the suggestion 8. Who is unregistering input device on request_irq() failure? =>Code added to handle unregistering input device on request_irq() failure 9. 'suspended' is boolean, so please use 'true' and 'false'. However, what is the point of these 2 functions anyway? =>These functions are not required and are removed 10. Do not call input_free_device() after calling input_unregister_device() =>Corrected 11. Why do you mange retrun value of spi_register_driver()? =>Corrected 12. No need for empty "return" statements. =>Corrected 13. Delayed work queue is replaced by kernel thread to process PENDET interrupts From ad032521ce86602fd83f313878b25c8fadb66b09 Mon Sep 17 00:00:00 2001 From: Sreedhara DS <sreedhara.ds@intel.com> Date: Wed, 2 Sep 2009 10:44:19 +0530 Subject: [PATCH] Resistive touch screen driver for Intel Moorestown platform Driver works with NEC, MAXIM and FreeScale PMICs Tested with moblin mrstouch Xorg touchscreen driver modified: Kconfig modified: Makefile new file: mrstouch.c Signed-off-by: Sreedhara DS <sreedhara.ds@intel.com> --- drivers/input/touchscreen/Kconfig | 9 + drivers/input/touchscreen/Makefile | 1 + drivers/input/touchscreen/mrstouch.c | 896 ++++++++++++++++++++++++++++++++++ 3 files changed, 906 insertions(+), 0 deletions(-) create mode 100644 drivers/input/touchscreen/mrstouch.c -- 1.5.4.5