--- /dev/null
+/*
+ * AD7879/AD7889 based touchscreen and GPIO driver
+ *
+ * Copyright (C) 2008-2010 Michael Hennerich, Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ *
+ * History:
+ * Copyright (c) 2005 David Brownell
+ * Copyright (c) 2006 Nokia Corporation
+ * Various changes: Imre Deak <imre.deak@nokia.com>
+ *
+ * Using code from:
+ * - corgi_ts.c
+ * Copyright (C) 2004-2005 Richard Purdie
+ * - omap_ts.[hc], ads7846.h, ts_osk.c
+ * Copyright (C) 2002 MontaVista Software
+ * Copyright (C) 2004 Texas Instruments
+ * Copyright (C) 2005 Dirk Behme
+ * - ad7877.c
+ * Copyright (C) 2006-2008 Analog Devices Inc.
+ */
+
+#include <linux/device.h>
+#include <linux/delay.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/slab.h>
+#include <linux/spi/spi.h>
+#include <linux/i2c.h>
+#include <linux/gpio.h>
+
+#include <linux/spi/ad7879.h>
+#include <linux/module.h>
+#include "ad7879.h"
+
+#define AD7879_REG_ZEROS 0
+#define AD7879_REG_CTRL1 1
+#define AD7879_REG_CTRL2 2
+#define AD7879_REG_CTRL3 3
+#define AD7879_REG_AUX1HIGH 4
+#define AD7879_REG_AUX1LOW 5
+#define AD7879_REG_TEMP1HIGH 6
+#define AD7879_REG_TEMP1LOW 7
+#define AD7879_REG_XPLUS 8
+#define AD7879_REG_YPLUS 9
+#define AD7879_REG_Z1 10
+#define AD7879_REG_Z2 11
+#define AD7879_REG_AUXVBAT 12
+#define AD7879_REG_TEMP 13
+#define AD7879_REG_REVID 14
+
+/* Control REG 1 */
+#define AD7879_TMR(x) ((x & 0xFF) << 0)
+#define AD7879_ACQ(x) ((x & 0x3) << 8)
+#define AD7879_MODE_NOC (0 << 10) /* Do not convert */
+#define AD7879_MODE_SCC (1 << 10) /* Single channel conversion */
+#define AD7879_MODE_SEQ0 (2 << 10) /* Sequence 0 in Slave Mode */
+#define AD7879_MODE_SEQ1 (3 << 10) /* Sequence 1 in Master Mode */
+#define AD7879_MODE_INT (1 << 15) /* PENIRQ disabled INT enabled */
+
+/* Control REG 2 */
+#define AD7879_FCD(x) ((x & 0x3) << 0)
+#define AD7879_RESET (1 << 4)
+#define AD7879_MFS(x) ((x & 0x3) << 5)
+#define AD7879_AVG(x) ((x & 0x3) << 7)
+#define AD7879_SER (1 << 9) /* non-differential */
+#define AD7879_DFR (0 << 9) /* differential */
+#define AD7879_GPIOPOL (1 << 10)
+#define AD7879_GPIODIR (1 << 11)
+#define AD7879_GPIO_DATA (1 << 12)
+#define AD7879_GPIO_EN (1 << 13)
+#define AD7879_PM(x) ((x & 0x3) << 14)
+#define AD7879_PM_SHUTDOWN (0)
+#define AD7879_PM_DYN (1)
+#define AD7879_PM_FULLON (2)
+
+/* Control REG 3 */
+#define AD7879_TEMPMASK_BIT (1<<15)
+#define AD7879_AUXVBATMASK_BIT (1<<14)
+#define AD7879_INTMODE_BIT (1<<13)
+#define AD7879_GPIOALERTMASK_BIT (1<<12)
+#define AD7879_AUXLOW_BIT (1<<11)
+#define AD7879_AUXHIGH_BIT (1<<10)
+#define AD7879_TEMPLOW_BIT (1<<9)
+#define AD7879_TEMPHIGH_BIT (1<<8)
+#define AD7879_YPLUS_BIT (1<<7)
+#define AD7879_XPLUS_BIT (1<<6)
+#define AD7879_Z1_BIT (1<<5)
+#define AD7879_Z2_BIT (1<<4)
+#define AD7879_AUX_BIT (1<<3)
+#define AD7879_VBAT_BIT (1<<2)
+#define AD7879_TEMP_BIT (1<<1)
+
+enum {
+ AD7879_SEQ_XPOS = 0,
+ AD7879_SEQ_YPOS = 1,
+ AD7879_SEQ_Z1 = 2,
+ AD7879_SEQ_Z2 = 3,
+ AD7879_NR_SENSE = 4,
+};
+
+#define MAX_12BIT ((1<<12)-1)
+#define TS_PEN_UP_TIMEOUT msecs_to_jiffies(50)
+
+struct ad7879 {
+ const struct ad7879_bus_ops *bops;
+
+ struct device *dev;
+ struct input_dev *input;
+ struct timer_list timer;
+#ifdef CONFIG_GPIOLIB
+ struct gpio_chip gc;
+ struct mutex mutex;
+#endif
+ unsigned int irq;
+ bool disabled; /* P: input->mutex */
+ bool suspended; /* P: input->mutex */
+ bool swap_xy;
+ u16 conversion_data[AD7879_NR_SENSE];
+ char phys[32];
+ u8 first_conversion_delay;
+ u8 acquisition_time;
+ u8 averaging;
+ u8 pen_down_acc_interval;
+ u8 median;
+ u16 x_plate_ohms;
+ u16 pressure_max;
+ u16 cmd_crtl1;
+ u16 cmd_crtl2;
+ u16 cmd_crtl3;
+ int x;
+ int y;
+ int Rt;
+};
+
+static int ad7879_read(struct ad7879 *ts, u8 reg)
+{
+ return ts->bops->read(ts->dev, reg);
+}
+
+static int ad7879_multi_read(struct ad7879 *ts, u8 first_reg, u8 count, u16 *buf)
+{
+ return ts->bops->multi_read(ts->dev, first_reg, count, buf);
+}
+
+static int ad7879_write(struct ad7879 *ts, u8 reg, u16 val)
+{
+ return ts->bops->write(ts->dev, reg, val);
+}
+
+static int ad7879_report(struct ad7879 *ts)
+{
+ struct input_dev *input_dev = ts->input;
+ unsigned Rt;
+ u16 x, y, z1, z2;
+
+ x = ts->conversion_data[AD7879_SEQ_XPOS] & MAX_12BIT;
+ y = ts->conversion_data[AD7879_SEQ_YPOS] & MAX_12BIT;
+ z1 = ts->conversion_data[AD7879_SEQ_Z1] & MAX_12BIT;
+ z2 = ts->conversion_data[AD7879_SEQ_Z2] & MAX_12BIT;
+
+ if (ts->swap_xy)
+ swap(x, y);
+
+ /*
+ * The samples processed here are already preprocessed by the AD7879.
+ * The preprocessing function consists of a median and an averaging
+ * filter. The combination of these two techniques provides a robust
+ * solution, discarding the spurious noise in the signal and keeping
+ * only the data of interest. The size of both filters is
+ * programmable. (dev.platform_data, see linux/spi/ad7879.h) Other
+ * user-programmable conversion controls include variable acquisition
+ * time, and first conversion delay. Up to 16 averages can be taken
+ * per conversion.
+ */
+
+ if (likely(x && z1)) {
+ /* compute touch pressure resistance using equation #1 */
+ Rt = (z2 - z1) * x * ts->x_plate_ohms;
+ Rt /= z1;
+ Rt = (Rt + 2047) >> 12;
+
+ /*
+ * Sample found inconsistent, pressure is beyond
+ * the maximum. Don't report it to user space.
+ */
+ if (Rt > ts->pressure_max)
+ return -EINVAL;
+
+ /*
+ * Note that we delay reporting events by one sample.
+ * This is done to avoid reporting last sample of the
+ * touch sequence, which may be incomplete if finger
+ * leaves the surface before last reading is taken.
+ */
+ if (timer_pending(&ts->timer)) {
+ /* Touch continues */
+ input_report_key(input_dev, BTN_TOUCH, 1);
+ input_report_abs(input_dev, ABS_X, ts->x);
+ input_report_abs(input_dev, ABS_Y, ts->y);
+ input_report_abs(input_dev, ABS_PRESSURE, ts->Rt);
+ input_sync(input_dev);
+ }
+
+ ts->x = x;
+ ts->y = y;
+ ts->Rt = Rt;
+
+ return 0;
+ }
+
+ return -EINVAL;
+}
+
+static void ad7879_ts_event_release(struct ad7879 *ts)
+{
+ struct input_dev *input_dev = ts->input;
+
+ input_report_abs(input_dev, ABS_PRESSURE, 0);
+ input_report_key(input_dev, BTN_TOUCH, 0);
+ input_sync(input_dev);
+}
+
+static void ad7879_timer(unsigned long handle)
+{
+ struct ad7879 *ts = (void *)handle;
+
+ ad7879_ts_event_release(ts);
+}
+
+static irqreturn_t ad7879_irq(int irq, void *handle)
+{
+ struct ad7879 *ts = handle;
+
+ ad7879_multi_read(ts, AD7879_REG_XPLUS, AD7879_NR_SENSE, ts->conversion_data);
+
+ if (!ad7879_report(ts))
+ mod_timer(&ts->timer, jiffies + TS_PEN_UP_TIMEOUT);
+
+ return IRQ_HANDLED;
+}
+
+static void __ad7879_enable(struct ad7879 *ts)
+{
+ ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
+ ad7879_write(ts, AD7879_REG_CTRL3, ts->cmd_crtl3);
+ ad7879_write(ts, AD7879_REG_CTRL1, ts->cmd_crtl1);
+
+ enable_irq(ts->irq);
+}
+
+static void __ad7879_disable(struct ad7879 *ts)
+{
+ u16 reg = (ts->cmd_crtl2 & ~AD7879_PM(-1)) |
+ AD7879_PM(AD7879_PM_SHUTDOWN);
+ disable_irq(ts->irq);
+
+ if (del_timer_sync(&ts->timer))
+ ad7879_ts_event_release(ts);
+
+ ad7879_write(ts, AD7879_REG_CTRL2, reg);
+}
+
+
+static int ad7879_open(struct input_dev *input)
+{
+ struct ad7879 *ts = input_get_drvdata(input);
+
+ /* protected by input->mutex */
+ if (!ts->disabled && !ts->suspended)
+ __ad7879_enable(ts);
+
+ return 0;
+}
+
+static void ad7879_close(struct input_dev* input)
+{
+ struct ad7879 *ts = input_get_drvdata(input);
+
+ /* protected by input->mutex */
+ if (!ts->disabled && !ts->suspended)
+ __ad7879_disable(ts);
+}
+
+static int __maybe_unused ad7879_suspend(struct device *dev)
+{
+ struct ad7879 *ts = dev_get_drvdata(dev);
+
+ mutex_lock(&ts->input->mutex);
+
+ if (!ts->suspended && !ts->disabled && ts->input->users)
+ __ad7879_disable(ts);
+
+ ts->suspended = true;
+
+ mutex_unlock(&ts->input->mutex);
+
+ return 0;
+}
+
+static int __maybe_unused ad7879_resume(struct device *dev)
+{
+ struct ad7879 *ts = dev_get_drvdata(dev);
+
+ mutex_lock(&ts->input->mutex);
+
+ if (ts->suspended && !ts->disabled && ts->input->users)
+ __ad7879_enable(ts);
+
+ ts->suspended = false;
+
+ mutex_unlock(&ts->input->mutex);
+
+ return 0;
+}
+
+SIMPLE_DEV_PM_OPS(ad7879_pm_ops, ad7879_suspend, ad7879_resume);
+EXPORT_SYMBOL(ad7879_pm_ops);
+
+static void ad7879_toggle(struct ad7879 *ts, bool disable)
+{
+ mutex_lock(&ts->input->mutex);
+
+ if (!ts->suspended && ts->input->users != 0) {
+
+ if (disable) {
+ if (ts->disabled)
+ __ad7879_enable(ts);
+ } else {
+ if (!ts->disabled)
+ __ad7879_disable(ts);
+ }
+ }
+
+ ts->disabled = disable;
+
+ mutex_unlock(&ts->input->mutex);
+}
+
+static ssize_t ad7879_disable_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct ad7879 *ts = dev_get_drvdata(dev);
+
+ return sprintf(buf, "%u\n", ts->disabled);
+}
+
+static ssize_t ad7879_disable_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct ad7879 *ts = dev_get_drvdata(dev);
+ unsigned int val;
+ int error;
+
+ error = kstrtouint(buf, 10, &val);
+ if (error)
+ return error;
+
+ ad7879_toggle(ts, val);
+
+ return count;
+}
+
+static DEVICE_ATTR(disable, 0664, ad7879_disable_show, ad7879_disable_store);
+
+static struct attribute *ad7879_attributes[] = {
+ &dev_attr_disable.attr,
+ NULL
+};
+
+static const struct attribute_group ad7879_attr_group = {
+ .attrs = ad7879_attributes,
+};
+
+#ifdef CONFIG_GPIOLIB
+static int ad7879_gpio_direction_input(struct gpio_chip *chip,
+ unsigned gpio)
+{
+ struct ad7879 *ts = container_of(chip, struct ad7879, gc);
+ int err;
+
+ mutex_lock(&ts->mutex);
+ ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIODIR | AD7879_GPIOPOL;
+ err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
+ mutex_unlock(&ts->mutex);
+
+ return err;
+}
+
+static int ad7879_gpio_direction_output(struct gpio_chip *chip,
+ unsigned gpio, int level)
+{
+ struct ad7879 *ts = container_of(chip, struct ad7879, gc);
+ int err;
+
+ mutex_lock(&ts->mutex);
+ ts->cmd_crtl2 &= ~AD7879_GPIODIR;
+ ts->cmd_crtl2 |= AD7879_GPIO_EN | AD7879_GPIOPOL;
+ if (level)
+ ts->cmd_crtl2 |= AD7879_GPIO_DATA;
+ else
+ ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
+
+ err = ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
+ mutex_unlock(&ts->mutex);
+
+ return err;
+}
+
+static int ad7879_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
+{
+ struct ad7879 *ts = container_of(chip, struct ad7879, gc);
+ u16 val;
+
+ mutex_lock(&ts->mutex);
+ val = ad7879_read(ts, AD7879_REG_CTRL2);
+ mutex_unlock(&ts->mutex);
+
+ return !!(val & AD7879_GPIO_DATA);
+}
+
+static void ad7879_gpio_set_value(struct gpio_chip *chip,
+ unsigned gpio, int value)
+{
+ struct ad7879 *ts = container_of(chip, struct ad7879, gc);
+
+ mutex_lock(&ts->mutex);
+ if (value)
+ ts->cmd_crtl2 |= AD7879_GPIO_DATA;
+ else
+ ts->cmd_crtl2 &= ~AD7879_GPIO_DATA;
+
+ ad7879_write(ts, AD7879_REG_CTRL2, ts->cmd_crtl2);
+ mutex_unlock(&ts->mutex);
+}
+
+static int ad7879_gpio_add(struct ad7879 *ts,
+ const struct ad7879_platform_data *pdata)
+{
+ int ret = 0;
+
+ mutex_init(&ts->mutex);
+
+ if (pdata->gpio_export) {
+ ts->gc.direction_input = ad7879_gpio_direction_input;
+ ts->gc.direction_output = ad7879_gpio_direction_output;
+ ts->gc.get = ad7879_gpio_get_value;
+ ts->gc.set = ad7879_gpio_set_value;
+ ts->gc.can_sleep = 1;
+ ts->gc.base = pdata->gpio_base;
+ ts->gc.ngpio = 1;
+ ts->gc.label = "AD7879-GPIO";
+ ts->gc.owner = THIS_MODULE;
+ ts->gc.dev = ts->dev;
+
+ ret = gpiochip_add(&ts->gc);
+ if (ret)
+ dev_err(ts->dev, "failed to register gpio %d\n",
+ ts->gc.base);
+ }
+
+ return ret;
+}
+
+static void ad7879_gpio_remove(struct ad7879 *ts)
+{
+ const struct ad7879_platform_data *pdata = dev_get_platdata(ts->dev);
+
+ if (pdata->gpio_export)
+ gpiochip_remove(&ts->gc);
+
+}
+#else
+static inline int ad7879_gpio_add(struct ad7879 *ts,
+ const struct ad7879_platform_data *pdata)
+{
+ return 0;
+}
+
+static inline void ad7879_gpio_remove(struct ad7879 *ts)
+{
+}
+#endif
+
+struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
+ const struct ad7879_bus_ops *bops)
+{
+ struct ad7879_platform_data *pdata = dev_get_platdata(dev);
+ struct ad7879 *ts;
+ struct input_dev *input_dev;
+ int err;
+ u16 revid;
+
+ if (!irq) {
+ dev_err(dev, "no IRQ?\n");
+ err = -EINVAL;
+ goto err_out;
+ }
+
+ if (!pdata) {
+ dev_err(dev, "no platform data?\n");
+ err = -EINVAL;
+ goto err_out;
+ }
+
+ ts = kzalloc(sizeof(*ts), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!ts || !input_dev) {
+ err = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ ts->bops = bops;
+ ts->dev = dev;
+ ts->input = input_dev;
+ ts->irq = irq;
+ ts->swap_xy = pdata->swap_xy;
+
+ setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts);
+
+ ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
+ ts->pressure_max = pdata->pressure_max ? : ~0;
+
+ ts->first_conversion_delay = pdata->first_conversion_delay;
+ ts->acquisition_time = pdata->acquisition_time;
+ ts->averaging = pdata->averaging;
+ ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
+ ts->median = pdata->median;
+
+ snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
+
+ input_dev->name = "AD7879 Touchscreen";
+ input_dev->phys = ts->phys;
+ input_dev->dev.parent = dev;
+ input_dev->id.bustype = bops->bustype;
+
+ input_dev->open = ad7879_open;
+ input_dev->close = ad7879_close;
+
+ input_set_drvdata(input_dev, ts);
+
+ __set_bit(EV_ABS, input_dev->evbit);
+ __set_bit(ABS_X, input_dev->absbit);
+ __set_bit(ABS_Y, input_dev->absbit);
+ __set_bit(ABS_PRESSURE, input_dev->absbit);
+
+ __set_bit(EV_KEY, input_dev->evbit);
+ __set_bit(BTN_TOUCH, input_dev->keybit);
+
+ 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);
+ input_set_abs_params(input_dev, ABS_PRESSURE,
+ pdata->pressure_min, pdata->pressure_max, 0, 0);
+
+ err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
+ if (err < 0) {
+ dev_err(dev, "Failed to write %s\n", input_dev->name);
+ goto err_free_mem;
+ }
+
+ revid = ad7879_read(ts, AD7879_REG_REVID);
+ input_dev->id.product = (revid & 0xff);
+ input_dev->id.version = revid >> 8;
+ if (input_dev->id.product != devid) {
+ dev_err(dev, "Failed to probe %s (%x vs %x)\n",
+ input_dev->name, devid, revid);
+ err = -ENODEV;
+ goto err_free_mem;
+ }
+
+ ts->cmd_crtl3 = AD7879_YPLUS_BIT |
+ AD7879_XPLUS_BIT |
+ AD7879_Z2_BIT |
+ AD7879_Z1_BIT |
+ AD7879_TEMPMASK_BIT |
+ AD7879_AUXVBATMASK_BIT |
+ AD7879_GPIOALERTMASK_BIT;
+
+ ts->cmd_crtl2 = AD7879_PM(AD7879_PM_DYN) | AD7879_DFR |
+ AD7879_AVG(ts->averaging) |
+ AD7879_MFS(ts->median) |
+ AD7879_FCD(ts->first_conversion_delay);
+
+ ts->cmd_crtl1 = AD7879_MODE_INT | AD7879_MODE_SEQ1 |
+ AD7879_ACQ(ts->acquisition_time) |
+ AD7879_TMR(ts->pen_down_acc_interval);
+
+ err = request_threaded_irq(ts->irq, NULL, ad7879_irq,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ dev_name(dev), ts);
+ if (err) {
+ dev_err(dev, "irq %d busy?\n", ts->irq);
+ goto err_free_mem;
+ }
+
+ __ad7879_disable(ts);
+
+ err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
+ if (err)
+ goto err_free_irq;
+
+ err = ad7879_gpio_add(ts, pdata);
+ if (err)
+ goto err_remove_attr;
+
+ err = input_register_device(input_dev);
+ if (err)
+ goto err_remove_gpio;
+
+ return ts;
+
+err_remove_gpio:
+ ad7879_gpio_remove(ts);
+err_remove_attr:
+ sysfs_remove_group(&dev->kobj, &ad7879_attr_group);
+err_free_irq:
+ free_irq(ts->irq, ts);
+err_free_mem:
+ input_free_device(input_dev);
+ kfree(ts);
+err_out:
+ return ERR_PTR(err);
+}
+EXPORT_SYMBOL(ad7879_probe);
+
+void ad7879_remove(struct ad7879 *ts)
+{
+ ad7879_gpio_remove(ts);
+ sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
+ free_irq(ts->irq, ts);
+ input_unregister_device(ts->input);
+ kfree(ts);
+}
+EXPORT_SYMBOL(ad7879_remove);
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("AD7879(-1) touchscreen Driver");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff