+++ /dev/null
-/*
- * Intel MID 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; if not, 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)
- * Ramesh Agarwal (ramesh.agarwal@intel.com)
- * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
- *
- * TODO:
- * review conversion of r/m/w sequences
- */
-
-#include <linux/module.h>
-#include <linux/input.h>
-#include <linux/interrupt.h>
-#include <linux/err.h>
-#include <linux/param.h>
-#include <linux/slab.h>
-#include <linux/platform_device.h>
-#include <linux/irq.h>
-#include <linux/delay.h>
-#include <asm/intel_scu_ipc.h>
-#include <linux/device.h>
-
-/* 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 channel BIAS constants */
-#define MRST_XBIAS 0x20
-#define MRST_YBIAS 0x40
-#define MRST_ZBIAS 0x80
-
-/* Touch screen coordinates */
-#define MRST_X_MIN 10
-#define MRST_X_MAX 1024
-#define MRST_X_FUZZ 5
-#define MRST_Y_MIN 10
-#define MRST_Y_MAX 1024
-#define MRST_Y_FUZZ 5
-#define MRST_PRESSURE_MIN 0
-#define MRST_PRESSURE_NOMINAL 50
-#define MRST_PRESSURE_MAX 100
-
-#define WAIT_ADC_COMPLETION 10 /* msec */
-
-/* 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 device *dev; /* device associated with touch screen */
- struct input_dev *input;
- char phys[32];
- u16 asr; /* Address selection register */
- int irq;
- unsigned int vendor; /* PMIC vendor */
- unsigned int rev; /* PMIC revision */
-
- int (*read_prepare)(struct mrstouch_dev *tsdev);
- int (*read)(struct mrstouch_dev *tsdev, u16 *x, u16 *y, u16 *z);
- int (*read_finish)(struct mrstouch_dev *tsdev);
-};
-
-
-/*************************** NEC and Maxim Interface ************************/
-
-static int mrstouch_nec_adc_read_prepare(struct mrstouch_dev *tsdev)
-{
- return intel_scu_ipc_update_register(PMIC_REG_MADCINT, 0, 0x20);
-}
-
-/*
- * Enables PENDET interrupt.
- */
-static int mrstouch_nec_adc_read_finish(struct mrstouch_dev *tsdev)
-{
- int err;
-
- err = intel_scu_ipc_update_register(PMIC_REG_MADCINT, 0x20, 0x20);
- if (!err)
- err = intel_scu_ipc_update_register(PMIC_REG_ADCCNTL1, 0, 0x05);
-
- return err;
-}
-
-/*
- * Reads PMIC ADC touch screen result
- * Reads ADC storage registers for higher 7 and lower 3 bits and
- * converts the two readings into a single value and turns off gain bit
- */
-static int mrstouch_ts_chan_read(u16 offset, u16 chan, u16 *vp, u16 *vm)
-{
- int err;
- u16 result;
- u32 res;
-
- result = PMIC_REG_ADCSNS0H + offset;
-
- if (chan == MRST_TS_CHAN12)
- result += 4;
-
- err = intel_scu_ipc_ioread32(result, &res);
- if (err)
- return err;
-
- /* Mash the bits up */
-
- *vp = (res & 0xFF) << 3; /* Highest 7 bits */
- *vp |= (res >> 8) & 0x07; /* Lower 3 bits */
- *vp &= 0x3FF;
-
- res >>= 16;
-
- *vm = (res & 0xFF) << 3; /* Highest 7 bits */
- *vm |= (res >> 8) & 0x07; /* Lower 3 bits */
- *vm &= 0x3FF;
-
- return 0;
-}
-
-/*
- * Enables 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 count;
- u16 chan, start;
- u16 reg[4];
- u8 data[4];
-
- chan = PMICADDR0 + offset;
- start = MRST_TS_CHAN10;
-
- for (count = 0; count <= 3; count++) {
- reg[count] = chan++;
- data[count] = bias | (start + count);
- }
-
- return intel_scu_ipc_writev(reg, data, 4);
-}
-
-/* To read touch screen channel values */
-static int mrstouch_nec_adc_read(struct mrstouch_dev *tsdev,
- u16 *x, u16 *y, u16 *z)
-{
- int err;
- u16 xm, ym, zm;
-
- /* configure Y bias for X channels */
- err = mrstouch_ts_bias_set(tsdev->asr, MRST_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, x, &xm);
- if (err)
- goto ipc_error;
-
- /* configure x bias for y channels */
- err = mrstouch_ts_bias_set(tsdev->asr, MRST_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, y, &ym);
- if (err)
- goto ipc_error;
-
- /* configure z bias for x and y channels */
- err = mrstouch_ts_bias_set(tsdev->asr, MRST_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, z, &zm);
- if (err)
- goto ipc_error;
-
- return 0;
-
-ipc_error:
- dev_err(tsdev->dev, "ipc error during adc read\n");
- return err;
-}
-
-
-/*************************** Freescale Interface ************************/
-
-static int mrstouch_fs_adc_read_prepare(struct mrstouch_dev *tsdev)
-{
- int err, count;
- u16 chan;
- u16 reg[5];
- u8 data[5];
-
- /* Stop the ADC */
- err = intel_scu_ipc_update_register(PMIC_REG_MADCINT, 0x00, 0x02);
- if (err)
- goto ipc_error;
-
- chan = PMICADDR0 + tsdev->asr;
-
- /* Set X BIAS */
- for (count = 0; count <= 3; count++) {
- reg[count] = chan++;
- data[count] = 0x2A;
- }
- reg[count] = chan++; /* Dummy */
- data[count] = 0;
-
- err = intel_scu_ipc_writev(reg, data, 5);
- if (err)
- goto ipc_error;
-
- msleep(WAIT_ADC_COMPLETION);
-
- /* Set Y BIAS */
- for (count = 0; count <= 3; count++) {
- reg[count] = chan++;
- data[count] = 0x4A;
- }
- reg[count] = chan++; /* Dummy */
- data[count] = 0;
-
- err = intel_scu_ipc_writev(reg, data, 5);
- if (err)
- goto ipc_error;
-
- msleep(WAIT_ADC_COMPLETION);
-
- /* Set Z BIAS */
- err = intel_scu_ipc_iowrite32(chan + 2, 0x8A8A8A8A);
- if (err)
- goto ipc_error;
-
- msleep(WAIT_ADC_COMPLETION);
-
- return 0;
-
-ipc_error:
- dev_err(tsdev->dev, "ipc error during %s\n", __func__);
- return err;
-}
-
-static int mrstouch_fs_adc_read(struct mrstouch_dev *tsdev,
- u16 *x, u16 *y, u16 *z)
-{
- int err;
- u16 result;
- u16 reg[4];
- u8 data[4];
-
- result = PMIC_REG_ADCSNS0H + tsdev->asr;
-
- reg[0] = result + 4;
- reg[1] = result + 5;
- reg[2] = result + 16;
- reg[3] = result + 17;
-
- err = intel_scu_ipc_readv(reg, data, 4);
- if (err)
- goto ipc_error;
-
- *x = data[0] << 3; /* Higher 7 bits */
- *x |= data[1] & 0x7; /* Lower 3 bits */
- *x &= 0x3FF;
-
- *y = data[2] << 3; /* Higher 7 bits */
- *y |= data[3] & 0x7; /* Lower 3 bits */
- *y &= 0x3FF;
-
- /* Read Z value */
- reg[0] = result + 28;
- reg[1] = result + 29;
-
- err = intel_scu_ipc_readv(reg, data, 4);
- if (err)
- goto ipc_error;
-
- *z = data[0] << 3; /* Higher 7 bits */
- *z |= data[1] & 0x7; /* Lower 3 bits */
- *z &= 0x3FF;
-
- return 0;
-
-ipc_error:
- dev_err(tsdev->dev, "ipc error during %s\n", __func__);
- return err;
-}
-
-static int mrstouch_fs_adc_read_finish(struct mrstouch_dev *tsdev)
-{
- int err, count;
- u16 chan;
- u16 reg[5];
- u8 data[5];
-
- /* Clear all TS channels */
- chan = PMICADDR0 + tsdev->asr;
- for (count = 0; count <= 4; count++) {
- reg[count] = chan++;
- data[count] = 0;
- }
- err = intel_scu_ipc_writev(reg, data, 5);
- if (err)
- goto ipc_error;
-
- for (count = 0; count <= 4; count++) {
- reg[count] = chan++;
- data[count] = 0;
- }
- err = intel_scu_ipc_writev(reg, data, 5);
- if (err)
- goto ipc_error;
-
- err = intel_scu_ipc_iowrite32(chan + 2, 0x00000000);
- if (err)
- goto ipc_error;
-
- /* Start ADC */
- err = intel_scu_ipc_update_register(PMIC_REG_MADCINT, 0x02, 0x02);
- if (err)
- goto ipc_error;
-
- return 0;
-
-ipc_error:
- dev_err(tsdev->dev, "ipc error during %s\n", __func__);
- return err;
-}
-
-static void mrstouch_report_event(struct input_dev *input,
- unsigned int x, unsigned int y, unsigned int z)
-{
- if (z > MRST_PRESSURE_NOMINAL) {
- /* Pen touched, report button touch and coordinates */
- input_report_key(input, BTN_TOUCH, 1);
- input_report_abs(input, ABS_X, x);
- input_report_abs(input, ABS_Y, y);
- } else {
- input_report_key(input, BTN_TOUCH, 0);
- }
-
- input_report_abs(input, ABS_PRESSURE, z);
- input_sync(input);
-}
-
-/* PENDET interrupt handler */
-static irqreturn_t mrstouch_pendet_irq(int irq, void *dev_id)
-{
- struct mrstouch_dev *tsdev = dev_id;
- u16 x, y, z;
-
- /*
- * Should we lower thread priority? Probably not, since we are
- * not spinning but sleeping...
- */
-
- if (tsdev->read_prepare(tsdev))
- goto out;
-
- do {
- if (tsdev->read(tsdev, &x, &y, &z))
- break;
-
- mrstouch_report_event(tsdev->input, x, y, z);
- } while (z > MRST_PRESSURE_NOMINAL);
-
- tsdev->read_finish(tsdev);
-
-out:
- return IRQ_HANDLED;
-}
-
-/* Utility to read PMIC ID */
-static int mrstouch_read_pmic_id(uint *vendor, uint *rev)
-{
- int err;
- u8 r;
-
- err = intel_scu_ipc_ioread8(PMIC_REG_ID1, &r);
- if (err)
- return err;
-
- *vendor = r & 0x7;
- *rev = (r >> 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 found = 0;
- int err, i;
- u8 r8;
-
- for (i = 0; i < MRSTOUCH_MAX_CHANNELS; i++) {
- err = intel_scu_ipc_ioread8(PMICADDR0 + i, &r8);
- if (err)
- return err;
-
- if (r8 == END_OF_CHANNEL) {
- found = i;
- break;
- }
- }
-
- if (tsdev->vendor == PMIC_VENDOR_FS) {
- if (found > MRSTOUCH_MAX_CHANNELS - 18)
- return -ENOSPC;
- } else {
- if (found > MRSTOUCH_MAX_CHANNELS - 4)
- return -ENOSPC;
- }
-
- return found;
-}
-
-
-/*
- * Writes touch screen channels to ADC address selection registers
- */
-static int mrstouch_ts_chan_set(uint offset)
-{
- u16 chan;
-
- int ret, count;
-
- chan = PMICADDR0 + offset;
- for (count = 0; count <= 3; count++) {
- ret = intel_scu_ipc_iowrite8(chan++, MRST_TS_CHAN10 + count);
- if (ret)
- return ret;
- }
- return intel_scu_ipc_iowrite8(chan++, END_OF_CHANNEL);
-}
-
-/* Initialize ADC */
-static int mrstouch_adc_init(struct mrstouch_dev *tsdev)
-{
- int err, start;
- u8 ra, rm;
-
- err = mrstouch_read_pmic_id(&tsdev->vendor, &tsdev->rev);
- if (err) {
- dev_err(tsdev->dev, "Unable to read PMIC id\n");
- return err;
- }
-
- switch (tsdev->vendor) {
- case PMIC_VENDOR_NEC:
- case PMIC_VENDOR_MAXIM:
- tsdev->read_prepare = mrstouch_nec_adc_read_prepare;
- tsdev->read = mrstouch_nec_adc_read;
- tsdev->read_finish = mrstouch_nec_adc_read_finish;
- break;
-
- case PMIC_VENDOR_FS:
- tsdev->read_prepare = mrstouch_fs_adc_read_prepare;
- tsdev->read = mrstouch_fs_adc_read;
- tsdev->read_finish = mrstouch_fs_adc_read_finish;
- break;
-
- default:
- dev_err(tsdev->dev,
- "Unsupported touchscreen: %d\n", tsdev->vendor);
- return -ENXIO;
- }
-
- start = mrstouch_chan_parse(tsdev);
- if (start < 0) {
- dev_err(tsdev->dev, "Unable to parse channels\n");
- 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 (continuous loop) in MAXIM stops PENDET
- * interrupt generation sometimes.
- */
-
- if (tsdev->vendor == PMIC_VENDOR_FS) {
- ra = 0xE0 | ADC_LOOP_DELAY0;
- rm = 0x5;
- } else {
- /* NEC and MAXIm not consistent with loop delay 0 */
- ra = 0xE0 | ADC_LOOP_DELAY1;
- rm = 0x0;
-
- /* configure touch screen channels */
- err = mrstouch_ts_chan_set(tsdev->asr);
- if (err)
- return err;
- }
-
- err = intel_scu_ipc_update_register(PMIC_REG_ADCCNTL1, ra, 0xE7);
- if (err)
- return err;
-
- err = intel_scu_ipc_update_register(PMIC_REG_MADCINT, rm, 0x03);
- if (err)
- return err;
-
- return 0;
-}
-
-
-/* Probe function for touch screen driver */
-static int mrstouch_probe(struct platform_device *pdev)
-{
- struct mrstouch_dev *tsdev;
- struct input_dev *input;
- int err;
- int irq;
-
- irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(&pdev->dev, "no interrupt assigned\n");
- return -EINVAL;
- }
-
- tsdev = devm_kzalloc(&pdev->dev, sizeof(struct mrstouch_dev),
- GFP_KERNEL);
- if (!tsdev) {
- dev_err(&pdev->dev, "unable to allocate memory\n");
- return -ENOMEM;
- }
-
- input = devm_input_allocate_device(&pdev->dev);
- if (!input) {
- dev_err(&pdev->dev, "unable to allocate input device\n");
- return -ENOMEM;
- }
-
- tsdev->dev = &pdev->dev;
- tsdev->input = input;
- tsdev->irq = irq;
-
- snprintf(tsdev->phys, sizeof(tsdev->phys),
- "%s/input0", dev_name(tsdev->dev));
-
- err = mrstouch_adc_init(tsdev);
- if (err) {
- dev_err(&pdev->dev, "ADC initialization failed\n");
- return err;
- }
-
- input->name = "mrst_touchscreen";
- input->phys = tsdev->phys;
- input->dev.parent = tsdev->dev;
-
- input->id.vendor = tsdev->vendor;
- input->id.version = tsdev->rev;
-
- input->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS);
- input->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH);
-
- input_set_abs_params(tsdev->input, ABS_X,
- MRST_X_MIN, MRST_X_MAX, MRST_X_FUZZ, 0);
- input_set_abs_params(tsdev->input, ABS_Y,
- MRST_Y_MIN, MRST_Y_MAX, MRST_Y_FUZZ, 0);
- input_set_abs_params(tsdev->input, ABS_PRESSURE,
- MRST_PRESSURE_MIN, MRST_PRESSURE_MAX, 0, 0);
-
- err = devm_request_threaded_irq(&pdev->dev, tsdev->irq, NULL,
- mrstouch_pendet_irq, IRQF_ONESHOT,
- "mrstouch", tsdev);
- if (err) {
- dev_err(tsdev->dev, "unable to allocate irq\n");
- return err;
- }
-
- err = input_register_device(tsdev->input);
- if (err) {
- dev_err(tsdev->dev, "unable to register input device\n");
- return err;
- }
-
- return 0;
-}
-
-static struct platform_driver mrstouch_driver = {
- .driver = {
- .name = "pmic_touch",
- },
- .probe = mrstouch_probe,
-};
-module_platform_driver(mrstouch_driver);
-
-MODULE_AUTHOR("Sreedhara Murthy. D.S, sreedhara.ds@intel.com");
-MODULE_DESCRIPTION("Intel Moorestown Resistive Touch Screen Driver");
-MODULE_LICENSE("GPL");