input: add driver for tnetv107x touchscreen controller

This patch adds support for tnetv107x's on-chip touchscreen controller.

Signed-off-by: Cyril Chemparathy <cyril@ti.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

3 files changed, 406 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 0069d9703fda..8d320289abf8 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -328,6 +328,15 @@ config TOUCHSCREEN_MIGOR
           To compile this driver as a module, choose M here: the
           module will be called migor_ts.
 
+config TOUCHSCREEN_TNETV107X
+        tristate "TI TNETV107X touchscreen support"
+        depends on ARCH_DAVINCI_TNETV107X
+        help
+          Say Y here if you want to use the TNETV107X touchscreen.
+
+          To compile this driver as a module, choose M here: the
+          module will be called tnetv107x-ts.
+
 config TOUCHSCREEN_TOUCHRIGHT
         tristate "Touchright serial touchscreen"
         select SERIO
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 28217e1dcafd..d41a964e673b 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -37,6 +37,7 @@ obj-$(CONFIG_TOUCHSCREEN_PENMOUNT)	+= penmount.o
 obj-$(CONFIG_TOUCHSCREEN_QT602240)      += qt602240_ts.o
 obj-$(CONFIG_TOUCHSCREEN_S3C2410)       += s3c2410_ts.o
 obj-$(CONFIG_TOUCHSCREEN_STMPE)         += stmpe-ts.o
+obj-$(CONFIG_TOUCHSCREEN_TNETV107X)     += tnetv107x-ts.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHIT213)    += touchit213.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHRIGHT)    += touchright.o
 obj-$(CONFIG_TOUCHSCREEN_TOUCHWIN)      += touchwin.o
diff --git a/drivers/input/touchscreen/tnetv107x-ts.c b/drivers/input/touchscreen/tnetv107x-ts.c
new file mode 100644
index 000000000000..cf1dba2e267c
--- /dev/null
+++ b/drivers/input/touchscreen/tnetv107x-ts.c
@@ -0,0 +1,396 @@
+/*
+ * Texas Instruments TNETV107X Touchscreen Driver
+ *
+ * Copyright (C) 2010 Texas Instruments
+ *
+ * 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.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/input.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/delay.h>
+#include <linux/ctype.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+
+#include <mach/tnetv107x.h>
+
+#define TSC_PENUP_POLL          (HZ / 5)
+#define IDLE_TIMEOUT            100 /* msec */
+
+/*
+ * The first and last samples of a touch interval are usually garbage and need
+ * to be filtered out with these devices.  The following definitions control
+ * the number of samples skipped.
+ */
+#define TSC_HEAD_SKIP           1
+#define TSC_TAIL_SKIP           1
+#define TSC_SKIP                (TSC_HEAD_SKIP + TSC_TAIL_SKIP + 1)
+#define TSC_SAMPLES             (TSC_SKIP + 1)
+
+/* Register Offsets */
+struct tsc_regs {
+        u32     rev;
+        u32     tscm;
+        u32     bwcm;
+        u32     swc;
+        u32     adcchnl;
+        u32     adcdata;
+        u32     chval[4];
+};
+
+/* TSC Mode Configuration Register (tscm) bits */
+#define WMODE           BIT(0)
+#define TSKIND          BIT(1)
+#define ZMEASURE_EN     BIT(2)
+#define IDLE            BIT(3)
+#define TSC_EN          BIT(4)
+#define STOP            BIT(5)
+#define ONE_SHOT        BIT(6)
+#define SINGLE          BIT(7)
+#define AVG             BIT(8)
+#define AVGNUM(x)       (((x) & 0x03) <<  9)
+#define PVSTC(x)        (((x) & 0x07) << 11)
+#define PON             BIT(14)
+#define PONBG           BIT(15)
+#define AFERST          BIT(16)
+
+/* ADC DATA Capture Register bits */
+#define DATA_VALID      BIT(16)
+
+/* Register Access Macros */
+#define tsc_read(ts, reg)               __raw_readl(&(ts)->regs->reg)
+#define tsc_write(ts, reg, val)         __raw_writel(val, &(ts)->regs->reg);
+#define tsc_set_bits(ts, reg, val)      \
+        tsc_write(ts, reg, tsc_read(ts, reg) | (val))
+#define tsc_clr_bits(ts, reg, val)      \
+        tsc_write(ts, reg, tsc_read(ts, reg) & ~(val))
+
+struct sample {
+        int x, y, p;
+};
+
+struct tsc_data {
+        struct input_dev                *input_dev;
+        struct resource                 *res;
+        struct tsc_regs __iomem         *regs;
+        struct timer_list               timer;
+        spinlock_t                      lock;
+        struct clk                      *clk;
+        struct device                   *dev;
+        int                             sample_count;
+        struct sample                   samples[TSC_SAMPLES];
+        int                             tsc_irq;
+};
+
+static int tsc_read_sample(struct tsc_data *ts, struct sample* sample)
+{
+        int     x, y, z1, z2, t, p = 0;
+        u32     val;
+
+        val = tsc_read(ts, chval[0]);
+        if (val & DATA_VALID)
+                x = val & 0xffff;
+        else
+                return -EINVAL;
+
+        y  = tsc_read(ts, chval[1]) & 0xffff;
+        z1 = tsc_read(ts, chval[2]) & 0xffff;
+        z2 = tsc_read(ts, chval[3]) & 0xffff;
+
+        if (z1) {
+                t = ((600 * x) * (z2 - z1));
+                p = t / (u32) (z1 << 12);
+                if (p < 0)
+                        p = 0;
+        }
+
+        sample->x  = x;
+        sample->y  = y;
+        sample->p  = p;
+
+        return 0;
+}
+
+static void tsc_poll(unsigned long data)
+{
+        struct tsc_data *ts = (struct tsc_data *)data;
+        unsigned long flags;
+        int i, val, x, y, p;
+
+        spin_lock_irqsave(&ts->lock, flags);
+
+        if (ts->sample_count >= TSC_SKIP) {
+                input_report_abs(ts->input_dev, ABS_PRESSURE, 0);
+                input_report_key(ts->input_dev, BTN_TOUCH, 0);
+                input_sync(ts->input_dev);
+        } else if (ts->sample_count > 0) {
+                /*
+                 * A touch event lasted less than our skip count.  Salvage and
+                 * report anyway.
+                 */
+                for (i = 0, val = 0; i < ts->sample_count; i++)
+                        val += ts->samples[i].x;
+                x = val / ts->sample_count;
+
+                for (i = 0, val = 0; i < ts->sample_count; i++)
+                        val += ts->samples[i].y;
+                y = val / ts->sample_count;
+
+                for (i = 0, val = 0; i < ts->sample_count; i++)
+                        val += ts->samples[i].p;
+                p = val / ts->sample_count;
+
+                input_report_abs(ts->input_dev, ABS_X, x);
+                input_report_abs(ts->input_dev, ABS_Y, y);
+                input_report_abs(ts->input_dev, ABS_PRESSURE, p);
+                input_report_key(ts->input_dev, BTN_TOUCH, 1);
+                input_sync(ts->input_dev);
+        }
+
+        ts->sample_count = 0;
+
+        spin_unlock_irqrestore(&ts->lock, flags);
+}
+
+static irqreturn_t tsc_irq(int irq, void *dev_id)
+{
+        struct tsc_data *ts = (struct tsc_data *)dev_id;
+        struct sample *sample;
+        int index;
+
+        spin_lock(&ts->lock);
+
+        index = ts->sample_count % TSC_SAMPLES;
+        sample = &ts->samples[index];
+        if (tsc_read_sample(ts, sample) < 0)
+                goto out;
+
+        if (++ts->sample_count >= TSC_SKIP) {
+                index = (ts->sample_count - TSC_TAIL_SKIP - 1) % TSC_SAMPLES;
+                sample = &ts->samples[index];
+
+                input_report_abs(ts->input_dev, ABS_X, sample->x);
+                input_report_abs(ts->input_dev, ABS_Y, sample->y);
+                input_report_abs(ts->input_dev, ABS_PRESSURE, sample->p);
+                if (ts->sample_count == TSC_SKIP)
+                        input_report_key(ts->input_dev, BTN_TOUCH, 1);
+                input_sync(ts->input_dev);
+        }
+        mod_timer(&ts->timer, jiffies + TSC_PENUP_POLL);
+out:
+        spin_unlock(&ts->lock);
+        return IRQ_HANDLED;
+}
+
+static int tsc_start(struct input_dev *dev)
+{
+        struct tsc_data *ts = input_get_drvdata(dev);
+        unsigned long timeout = jiffies + msecs_to_jiffies(IDLE_TIMEOUT);
+        u32 val;
+
+        clk_enable(ts->clk);
+
+        /* Go to idle mode, before any initialization */
+        while (time_after(timeout, jiffies)) {
+                if (tsc_read(ts, tscm) & IDLE)
+                        break;
+        }
+
+        if (time_before(timeout, jiffies)) {
+                dev_warn(ts->dev, "timeout waiting for idle\n");
+                clk_disable(ts->clk);
+                return -EIO;
+        }
+
+        /* Configure TSC Control register*/
+        val = (PONBG | PON | PVSTC(4) | ONE_SHOT | ZMEASURE_EN);
+        tsc_write(ts, tscm, val);
+
+        /* Bring TSC out of reset: Clear AFE reset bit */
+        val &= ~(AFERST);
+        tsc_write(ts, tscm, val);
+
+        /* Configure all pins for hardware control*/
+        tsc_write(ts, bwcm, 0);
+
+        /* Finally enable the TSC */
+        tsc_set_bits(ts, tscm, TSC_EN);
+
+        return 0;
+}
+
+static void tsc_stop(struct input_dev *dev)
+{
+        struct tsc_data *ts = input_get_drvdata(dev);
+
+        tsc_clr_bits(ts, tscm, TSC_EN);
+        synchronize_irq(ts->tsc_irq);
+        del_timer_sync(&ts->timer);
+        clk_disable(ts->clk);
+}
+
+static int __devinit tsc_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct tsc_data *ts;
+        int error = 0;
+        u32 rev = 0;
+
+        ts = kzalloc(sizeof(struct tsc_data), GFP_KERNEL);
+        if (!ts) {
+                dev_err(dev, "cannot allocate device info\n");
+                return -ENOMEM;
+        }
+
+        ts->dev = dev;
+        spin_lock_init(&ts->lock);
+        setup_timer(&ts->timer, tsc_poll, (unsigned long)ts);
+        platform_set_drvdata(pdev, ts);
+
+        ts->tsc_irq = platform_get_irq(pdev, 0);
+        if (ts->tsc_irq < 0) {
+                dev_err(dev, "cannot determine device interrupt\n");
+                error = -ENODEV;
+                goto error_res;
+        }
+
+        ts->res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        if (!ts->res) {
+                dev_err(dev, "cannot determine register area\n");
+                error = -ENODEV;
+                goto error_res;
+        }
+
+        if (!request_mem_region(ts->res->start, resource_size(ts->res),
+                                pdev->name)) {
+                dev_err(dev, "cannot claim register memory\n");
+                ts->res = NULL;
+                error = -EINVAL;
+                goto error_res;
+        }
+
+        ts->regs = ioremap(ts->res->start, resource_size(ts->res));
+        if (!ts->regs) {
+                dev_err(dev, "cannot map register memory\n");
+                error = -ENOMEM;
+                goto error_map;
+        }
+
+        ts->clk = clk_get(dev, NULL);
+        if (!ts->clk) {
+                dev_err(dev, "cannot claim device clock\n");
+                error = -EINVAL;
+                goto error_clk;
+        }
+
+        error = request_threaded_irq(ts->tsc_irq, NULL, tsc_irq, 0,
+                                     dev_name(dev), ts);
+        if (error < 0) {
+                dev_err(ts->dev, "Could not allocate ts irq\n");
+                goto error_irq;
+        }
+
+        ts->input_dev = input_allocate_device();
+        if (!ts->input_dev) {
+                dev_err(dev, "cannot allocate input device\n");
+                error = -ENOMEM;
+                goto error_input;
+        }
+        input_set_drvdata(ts->input_dev, ts);
+
+        ts->input_dev->name       = pdev->name;
+        ts->input_dev->id.bustype = BUS_HOST;
+        ts->input_dev->dev.parent = &pdev->dev;
+        ts->input_dev->open       = tsc_start;
+        ts->input_dev->close      = tsc_stop;
+
+        clk_enable(ts->clk);
+        rev = tsc_read(ts, rev);
+        ts->input_dev->id.product = ((rev >>  8) & 0x07);
+        ts->input_dev->id.version = ((rev >> 16) & 0xfff);
+        clk_disable(ts->clk);
+
+        __set_bit(EV_KEY,    ts->input_dev->evbit);
+        __set_bit(EV_ABS,    ts->input_dev->evbit);
+        __set_bit(BTN_TOUCH, ts->input_dev->keybit);
+
+        input_set_abs_params(ts->input_dev, ABS_X, 0, 0xffff, 5, 0);
+        input_set_abs_params(ts->input_dev, ABS_Y, 0, 0xffff, 5, 0);
+        input_set_abs_params(ts->input_dev, ABS_PRESSURE, 0, 4095, 128, 0);
+
+        error = input_register_device(ts->input_dev);
+        if (error < 0) {
+                dev_err(dev, "failed input device registration\n");
+                goto error_reg;
+        }
+
+        return 0;
+
+error_reg:
+        input_free_device(ts->input_dev);
+error_input:
+        free_irq(ts->tsc_irq, ts);
+error_irq:
+        clk_put(ts->clk);
+error_clk:
+        iounmap(ts->regs);
+error_map:
+        release_mem_region(ts->res->start, resource_size(ts->res));
+error_res:
+        platform_set_drvdata(pdev, NULL);
+        kfree(ts);
+
+        return error;
+}
+
+static int __devexit tsc_remove(struct platform_device *pdev)
+{
+        struct tsc_data *ts = platform_get_drvdata(pdev);
+
+        input_unregister_device(ts->input_dev);
+        free_irq(ts->tsc_irq, ts);
+        clk_put(ts->clk);
+        iounmap(ts->regs);
+        release_mem_region(ts->res->start, resource_size(ts->res));
+        platform_set_drvdata(pdev, NULL);
+        kfree(ts);
+
+        return 0;
+}
+
+static struct platform_driver tsc_driver = {
+        .probe          = tsc_probe,
+        .remove         = __devexit_p(tsc_remove),
+        .driver.name    = "tnetv107x-ts",
+        .driver.owner   = THIS_MODULE,
+};
+
+static int __init tsc_init(void)
+{
+        return platform_driver_register(&tsc_driver);
+}
+
+static void __exit tsc_exit(void)
+{
+        platform_driver_unregister(&tsc_driver);
+}
+
+module_init(tsc_init);
+module_exit(tsc_exit);
+
+MODULE_AUTHOR("Cyril Chemparathy");
+MODULE_DESCRIPTION("TNETV107X Touchscreen Driver");
+MODULE_ALIAS("platform: tnetv107x-ts");
+MODULE_LICENSE("GPL");