1 files changed, 687 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/intel-mid-touch.c b/drivers/input/touchscreen/intel-mid-touch.c
new file mode 100644
index 000000000000..c0307b22d86f
--- /dev/null
+++ b/drivers/input/touchscreen/intel-mid-touch.c
@@ -0,0 +1,687 @@
+/*
+ * 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/init.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>
+
+/* 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 __devinit 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 __devinit mrstouch_chan_parse(struct mrstouch_dev *tsdev)
+{
+        int err, i, found;
+        u8 r8;
+
+        found = -1;
+
+        for (i = 0; i < MRSTOUCH_MAX_CHANNELS; i++) {
+                if (found >= 0)
+                        break;
+
+                err = intel_scu_ipc_ioread8(PMICADDR0 + i, &r8);
+                if (err)
+                        return err;
+
+                if (r8 == 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 -ENOSPC;
+        } else {
+                if (found && found > (MRSTOUCH_MAX_CHANNELS - 4))
+                        return -ENOSPC;
+        }
+        return found;
+}
+
+
+/*
+ * Writes touch screen channels to ADC address selection registers
+ */
+static int __devinit 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 __devinit 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 (continous 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 __devinit 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 = kzalloc(sizeof(struct mrstouch_dev), GFP_KERNEL);
+        input = input_allocate_device();
+        if (!tsdev || !input) {
+                dev_err(&pdev->dev, "unable to allocate memory\n");
+                err = -ENOMEM;
+                goto err_free_mem;
+        }
+
+        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");
+                goto err_free_mem;
+        }
+
+        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 = request_threaded_irq(tsdev->irq, NULL, mrstouch_pendet_irq,
+                                   0, "mrstouch", tsdev);
+        if (err) {
+                dev_err(tsdev->dev, "unable to allocate irq\n");
+                goto err_free_mem;
+        }
+
+        err = input_register_device(tsdev->input);
+        if (err) {
+                dev_err(tsdev->dev, "unable to register input device\n");
+                goto err_free_irq;
+        }
+
+        platform_set_drvdata(pdev, tsdev);
+        return 0;
+
+err_free_irq:
+        free_irq(tsdev->irq, tsdev);
+err_free_mem:
+        input_free_device(input);
+        kfree(tsdev);
+        return err;
+}
+
+static int __devexit mrstouch_remove(struct platform_device *pdev)
+{
+        struct mrstouch_dev *tsdev = platform_get_drvdata(pdev);
+
+        free_irq(tsdev->irq, tsdev);
+        input_unregister_device(tsdev->input);
+        kfree(tsdev);
+
+        platform_set_drvdata(pdev, NULL);
+
+        return 0;
+}
+
+static struct platform_driver mrstouch_driver = {
+        .driver = {
+                .name   = "pmic_touch",
+                .owner  = THIS_MODULE,
+        },
+        .probe          = mrstouch_probe,
+        .remove         = __devexit_p(mrstouch_remove),
+};
+
+static int __init mrstouch_init(void)
+{
+        return platform_driver_register(&mrstouch_driver);
+}
+module_init(mrstouch_init);
+
+static void __exit mrstouch_exit(void)
+{
+        platform_driver_unregister(&mrstouch_driver);
+}
+module_exit(mrstouch_exit);
+
+MODULE_AUTHOR("Sreedhara Murthy. D.S, sreedhara.ds@intel.com");
+MODULE_DESCRIPTION("Intel Moorestown Resistive Touch Screen Driver");
+MODULE_LICENSE("GPL");