Input: ili210x - add support for Ilitek ILI210x based touchscreens

The driver supports chipsets ILI2102, ILI2102s, ILI2103, ILI2103s and
ILI2105. Such kind of controllers can be found in Amazon Kindle Fire
devices.

Reviewed-by: Jan Paesmans <jan.paesmans@gmail.com>
Reviewed-by: Henrik Rydberg <rydberg@euromail.se>
Signed-off-by: Olivier Sobrie <olivier@sobrie.be>
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

3 files changed, 376 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index fc087b3c95cf..97b31a0e0525 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -243,6 +243,21 @@ config TOUCHSCREEN_FUJITSU
           To compile this driver as a module, choose M here: the
           module will be called fujitsu-ts.
 
+config TOUCHSCREEN_ILI210X
+        tristate "Ilitek ILI210X based touchscreen"
+        depends on I2C
+        help
+          Say Y here if you have a ILI210X based touchscreen
+          controller. This driver supports models ILI2102,
+          ILI2102s, ILI2103, ILI2103s and ILI2105.
+          Such kind of chipsets can be found in Amazon Kindle Fire
+          touchscreens.
+
+          If unsure, say N.
+
+          To compile this driver as a module, choose M here: the
+          module will be called ili210x.
+
 config TOUCHSCREEN_S3C2410
         tristate "Samsung S3C2410/generic touchscreen input driver"
         depends on ARCH_S3C2410 || SAMSUNG_DEV_TS
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index e748fb837759..3d5cf8cbf89c 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -29,6 +29,7 @@ obj-$(CONFIG_TOUCHSCREEN_EETI)		+= eeti_ts.o
 obj-$(CONFIG_TOUCHSCREEN_ELO)           += elo.o
 obj-$(CONFIG_TOUCHSCREEN_EGALAX)        += egalax_ts.o
 obj-$(CONFIG_TOUCHSCREEN_FUJITSU)       += fujitsu_ts.o
+obj-$(CONFIG_TOUCHSCREEN_ILI210X)       += ili210x.o
 obj-$(CONFIG_TOUCHSCREEN_INEXIO)        += inexio.o
 obj-$(CONFIG_TOUCHSCREEN_INTEL_MID)     += intel-mid-touch.o
 obj-$(CONFIG_TOUCHSCREEN_LPC32XX)       += lpc32xx_ts.o
diff --git a/drivers/input/touchscreen/ili210x.c b/drivers/input/touchscreen/ili210x.c
new file mode 100644
index 000000000000..c0044175a921
--- /dev/null
+++ b/drivers/input/touchscreen/ili210x.c
@@ -0,0 +1,360 @@
+#include <linux/module.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/delay.h>
+#include <linux/workqueue.h>
+#include <linux/input/ili210x.h>
+
+#define MAX_TOUCHES             2
+#define DEFAULT_POLL_PERIOD     20
+
+/* Touchscreen commands */
+#define REG_TOUCHDATA           0x10
+#define REG_PANEL_INFO          0x20
+#define REG_FIRMWARE_VERSION    0x40
+#define REG_CALIBRATE           0xcc
+
+struct finger {
+        u8 x_low;
+        u8 x_high;
+        u8 y_low;
+        u8 y_high;
+} __packed;
+
+struct touchdata {
+        u8 status;
+        struct finger finger[MAX_TOUCHES];
+} __packed;
+
+struct panel_info {
+        struct finger finger_max;
+        u8 xchannel_num;
+        u8 ychannel_num;
+} __packed;
+
+struct firmware_version {
+        u8 id;
+        u8 major;
+        u8 minor;
+} __packed;
+
+struct ili210x {
+        struct i2c_client *client;
+        struct input_dev *input;
+        bool (*get_pendown_state)(void);
+        unsigned int poll_period;
+        struct delayed_work dwork;
+};
+
+static int ili210x_read_reg(struct i2c_client *client, u8 reg, void *buf,
+                            size_t len)
+{
+        struct i2c_msg msg[2] = {
+                {
+                        .addr   = client->addr,
+                        .flags  = 0,
+                        .len    = 1,
+                        .buf    = &reg,
+                },
+                {
+                        .addr   = client->addr,
+                        .flags  = I2C_M_RD,
+                        .len    = len,
+                        .buf    = buf,
+                }
+        };
+
+        if (i2c_transfer(client->adapter, msg, 2) != 2) {
+                dev_err(&client->dev, "i2c transfer failed\n");
+                return -EIO;
+        }
+
+        return 0;
+}
+
+static void ili210x_report_events(struct input_dev *input,
+                                  const struct touchdata *touchdata)
+{
+        int i;
+        bool touch;
+        unsigned int x, y;
+        const struct finger *finger;
+
+        for (i = 0; i < MAX_TOUCHES; i++) {
+                input_mt_slot(input, i);
+
+                finger = &touchdata->finger[i];
+
+                touch = touchdata->status & (1 << i);
+                input_mt_report_slot_state(input, MT_TOOL_FINGER, touch);
+                if (touch) {
+                        x = finger->x_low | (finger->x_high << 8);
+                        y = finger->y_low | (finger->y_high << 8);
+
+                        input_report_abs(input, ABS_MT_POSITION_X, x);
+                        input_report_abs(input, ABS_MT_POSITION_Y, y);
+                }
+        }
+
+        input_mt_report_pointer_emulation(input, false);
+        input_sync(input);
+}
+
+static bool get_pendown_state(const struct ili210x *priv)
+{
+        bool state = false;
+
+        if (priv->get_pendown_state)
+                state = priv->get_pendown_state();
+
+        return state;
+}
+
+static void ili210x_work(struct work_struct *work)
+{
+        struct ili210x *priv = container_of(work, struct ili210x,
+                                            dwork.work);
+        struct i2c_client *client = priv->client;
+        struct touchdata touchdata;
+        int error;
+
+        error = ili210x_read_reg(client, REG_TOUCHDATA,
+                                 &touchdata, sizeof(touchdata));
+        if (error) {
+                dev_err(&client->dev,
+                        "Unable to get touchdata, err = %d\n", error);
+                return;
+        }
+
+        ili210x_report_events(priv->input, &touchdata);
+
+        if ((touchdata.status & 0xf3) || get_pendown_state(priv))
+                schedule_delayed_work(&priv->dwork,
+                                      msecs_to_jiffies(priv->poll_period));
+}
+
+static irqreturn_t ili210x_irq(int irq, void *irq_data)
+{
+        struct ili210x *priv = irq_data;
+
+        schedule_delayed_work(&priv->dwork, 0);
+
+        return IRQ_HANDLED;
+}
+
+static ssize_t ili210x_calibrate(struct device *dev,
+                                 struct device_attribute *attr,
+                                 const char *buf, size_t count)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+        struct ili210x *priv = i2c_get_clientdata(client);
+        unsigned long calibrate;
+        int rc;
+        u8 cmd = REG_CALIBRATE;
+
+        if (kstrtoul(buf, 10, &calibrate))
+                return -EINVAL;
+
+        if (calibrate > 1)
+                return -EINVAL;
+
+        if (calibrate) {
+                rc = i2c_master_send(priv->client, &cmd, sizeof(cmd));
+                if (rc != sizeof(cmd))
+                        return -EIO;
+        }
+
+        return count;
+}
+static DEVICE_ATTR(calibrate, 0644, NULL, ili210x_calibrate);
+
+static struct attribute *ili210x_attributes[] = {
+        &dev_attr_calibrate.attr,
+        NULL,
+};
+
+static const struct attribute_group ili210x_attr_group = {
+        .attrs = ili210x_attributes,
+};
+
+static int __devinit ili210x_i2c_probe(struct i2c_client *client,
+                                       const struct i2c_device_id *id)
+{
+        struct device *dev = &client->dev;
+        const struct ili210x_platform_data *pdata = dev->platform_data;
+        struct ili210x *priv;
+        struct input_dev *input;
+        struct panel_info panel;
+        struct firmware_version firmware;
+        int xmax, ymax;
+        int error;
+
+        dev_dbg(dev, "Probing for ILI210X I2C Touschreen driver");
+
+        if (!pdata) {
+                dev_err(dev, "No platform data!\n");
+                return -EINVAL;
+        }
+
+        if (client->irq <= 0) {
+                dev_err(dev, "No IRQ!\n");
+                return -EINVAL;
+        }
+
+        /* Get firmware version */
+        error = ili210x_read_reg(client, REG_FIRMWARE_VERSION,
+                                 &firmware, sizeof(firmware));
+        if (error) {
+                dev_err(dev, "Failed to get firmware version, err: %d\n",
+                        error);
+                return error;
+        }
+
+        /* get panel info */
+        error = ili210x_read_reg(client, REG_PANEL_INFO, &panel, sizeof(panel));
+        if (error) {
+                dev_err(dev, "Failed to get panel informations, err: %d\n",
+                        error);
+                return error;
+        }
+
+        xmax = panel.finger_max.x_low | (panel.finger_max.x_high << 8);
+        ymax = panel.finger_max.y_low | (panel.finger_max.y_high << 8);
+
+        priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+        input = input_allocate_device();
+        if (!priv || !input) {
+                error = -ENOMEM;
+                goto err_free_mem;
+        }
+
+        priv->client = client;
+        priv->input = input;
+        priv->get_pendown_state = pdata->get_pendown_state;
+        priv->poll_period = pdata->poll_period ? : DEFAULT_POLL_PERIOD;
+        INIT_DELAYED_WORK(&priv->dwork, ili210x_work);
+
+        /* Setup input device */
+        input->name = "ILI210x Touchscreen";
+        input->id.bustype = BUS_I2C;
+        input->dev.parent = dev;
+
+        __set_bit(EV_SYN, input->evbit);
+        __set_bit(EV_KEY, input->evbit);
+        __set_bit(EV_ABS, input->evbit);
+        __set_bit(BTN_TOUCH, input->keybit);
+
+        /* Single touch */
+        input_set_abs_params(input, ABS_X, 0, xmax, 0, 0);
+        input_set_abs_params(input, ABS_Y, 0, ymax, 0, 0);
+
+        /* Multi touch */
+        input_mt_init_slots(input, MAX_TOUCHES);
+        input_set_abs_params(input, ABS_MT_POSITION_X, 0, xmax, 0, 0);
+        input_set_abs_params(input, ABS_MT_POSITION_Y, 0, ymax, 0, 0);
+
+        input_set_drvdata(input, priv);
+        i2c_set_clientdata(client, priv);
+
+        error = request_irq(client->irq, ili210x_irq, pdata->irq_flags,
+                            client->name, priv);
+        if (error) {
+                dev_err(dev, "Unable to request touchscreen IRQ, err: %d\n",
+                        error);
+                goto err_free_mem;
+        }
+
+        error = sysfs_create_group(&dev->kobj, &ili210x_attr_group);
+        if (error) {
+                dev_err(dev, "Unable to create sysfs attributes, err: %d\n",
+                        error);
+                goto err_free_irq;
+        }
+
+        error = input_register_device(priv->input);
+        if (error) {
+                dev_err(dev, "Cannot regiser input device, err: %d\n", error);
+                goto err_remove_sysfs;
+        }
+
+        device_init_wakeup(&client->dev, 1);
+
+        dev_dbg(dev,
+                "ILI210x initialized (IRQ: %d), firmware version %d.%d.%d",
+                client->irq, firmware.id, firmware.major, firmware.minor);
+
+        return 0;
+
+err_remove_sysfs:
+        sysfs_remove_group(&dev->kobj, &ili210x_attr_group);
+err_free_irq:
+        free_irq(client->irq, priv);
+err_free_mem:
+        input_free_device(input);
+        kfree(priv);
+        return error;
+}
+
+static int __devexit ili210x_i2c_remove(struct i2c_client *client)
+{
+        struct ili210x *priv = i2c_get_clientdata(client);
+
+        sysfs_remove_group(&client->dev.kobj, &ili210x_attr_group);
+        free_irq(priv->client->irq, priv);
+        cancel_delayed_work_sync(&priv->dwork);
+        input_unregister_device(priv->input);
+        kfree(priv);
+
+        return 0;
+}
+
+#ifdef CONFIG_PM_SLEEP
+static int ili210x_i2c_suspend(struct device *dev)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+
+        if (device_may_wakeup(&client->dev))
+                enable_irq_wake(client->irq);
+
+        return 0;
+}
+
+static int ili210x_i2c_resume(struct device *dev)
+{
+        struct i2c_client *client = to_i2c_client(dev);
+
+        if (device_may_wakeup(&client->dev))
+                disable_irq_wake(client->irq);
+
+        return 0;
+}
+#endif
+
+static SIMPLE_DEV_PM_OPS(ili210x_i2c_pm,
+                         ili210x_i2c_suspend, ili210x_i2c_resume);
+
+static const struct i2c_device_id ili210x_i2c_id[] = {
+        { "ili210x", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(i2c, ili210x_i2c_id);
+
+static struct i2c_driver ili210x_ts_driver = {
+        .driver = {
+                .name = "ili210x_i2c",
+                .owner = THIS_MODULE,
+                .pm = &ili210x_i2c_pm,
+        },
+        .id_table = ili210x_i2c_id,
+        .probe = ili210x_i2c_probe,
+        .remove = __devexit_p(ili210x_i2c_remove),
+};
+
+module_i2c_driver(ili210x_ts_driver);
+
+MODULE_AUTHOR("Olivier Sobrie <olivier@sobrie.be>");
+MODULE_DESCRIPTION("ILI210X I2C Touchscreen Driver");
+MODULE_LICENSE("GPL");