3 files changed, 409 insertions, 0 deletions

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index e1d8003d01f8..568a0200fbc2 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -295,6 +295,19 @@ config TOUCHSCREEN_FUJITSU
           To compile this driver as a module, choose M here: the
           module will be called fujitsu-ts.
 
+config TOUCHSCREEN_GOODIX
+        tristate "Goodix I2C touchscreen"
+        depends on I2C && ACPI
+        help
+          Say Y here if you have the Goodix touchscreen (such as one
+          installed in Onda v975w tablets) connected to your
+          system.
+
+          If unsure, say N.
+
+          To compile this driver as a module, choose M here: the
+          module will be called goodix.
+
 config TOUCHSCREEN_ILI210X
         tristate "Ilitek ILI210X based touchscreen"
         depends on I2C
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 090e61cc9171..dab4a56ac98e 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -34,6 +34,7 @@ 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-$(CONFIG_TOUCHSCREEN_GOODIX)        += goodix.o
 obj-$(CONFIG_TOUCHSCREEN_ILI210X)       += ili210x.o
 obj-$(CONFIG_TOUCHSCREEN_INEXIO)        += inexio.o
 obj-$(CONFIG_TOUCHSCREEN_INTEL_MID)     += intel-mid-touch.o
diff --git a/drivers/input/touchscreen/goodix.c b/drivers/input/touchscreen/goodix.c
new file mode 100644
index 000000000000..ca196689f025
--- /dev/null
+++ b/drivers/input/touchscreen/goodix.c
@@ -0,0 +1,395 @@
+/*
+ *  Driver for Goodix Touchscreens
+ *
+ *  Copyright (c) 2014 Red Hat Inc.
+ *
+ *  This code is based on gt9xx.c authored by andrew@goodix.com:
+ *
+ *  2010 - 2012 Goodix Technology.
+ */
+
+/*
+ * 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.
+ */
+
+#include <linux/kernel.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/module.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+
+struct goodix_ts_data {
+        struct i2c_client *client;
+        struct input_dev *input_dev;
+        int abs_x_max;
+        int abs_y_max;
+        unsigned int max_touch_num;
+        unsigned int int_trigger_type;
+};
+
+#define GOODIX_MAX_HEIGHT               4096
+#define GOODIX_MAX_WIDTH                4096
+#define GOODIX_INT_TRIGGER              1
+#define GOODIX_CONTACT_SIZE             8
+#define GOODIX_MAX_CONTACTS             10
+
+#define GOODIX_CONFIG_MAX_LENGTH        240
+
+/* Register defines */
+#define GOODIX_READ_COOR_ADDR           0x814E
+#define GOODIX_REG_CONFIG_DATA          0x8047
+#define GOODIX_REG_VERSION              0x8140
+
+#define RESOLUTION_LOC          1
+#define TRIGGER_LOC             6
+
+static const unsigned long goodix_irq_flags[] = {
+        IRQ_TYPE_EDGE_RISING,
+        IRQ_TYPE_EDGE_FALLING,
+        IRQ_TYPE_LEVEL_LOW,
+        IRQ_TYPE_LEVEL_HIGH,
+};
+
+/**
+ * goodix_i2c_read - read data from a register of the i2c slave device.
+ *
+ * @client: i2c device.
+ * @reg: the register to read from.
+ * @buf: raw write data buffer.
+ * @len: length of the buffer to write
+ */
+static int goodix_i2c_read(struct i2c_client *client,
+                                u16 reg, u8 *buf, int len)
+{
+        struct i2c_msg msgs[2];
+        u16 wbuf = cpu_to_be16(reg);
+        int ret;
+
+        msgs[0].flags = 0;
+        msgs[0].addr  = client->addr;
+        msgs[0].len   = 2;
+        msgs[0].buf   = (u8 *) &wbuf;
+
+        msgs[1].flags = I2C_M_RD;
+        msgs[1].addr  = client->addr;
+        msgs[1].len   = len;
+        msgs[1].buf   = buf;
+
+        ret = i2c_transfer(client->adapter, msgs, 2);
+        return ret < 0 ? ret : (ret != ARRAY_SIZE(msgs) ? -EIO : 0);
+}
+
+static int goodix_ts_read_input_report(struct goodix_ts_data *ts, u8 *data)
+{
+        int touch_num;
+        int error;
+
+        error = goodix_i2c_read(ts->client, GOODIX_READ_COOR_ADDR, data,
+                                GOODIX_CONTACT_SIZE + 1);
+        if (error) {
+                dev_err(&ts->client->dev, "I2C transfer error: %d\n", error);
+                return error;
+        }
+
+        touch_num = data[0] & 0x0f;
+        if (touch_num > GOODIX_MAX_CONTACTS)
+                return -EPROTO;
+
+        if (touch_num > 1) {
+                data += 1 + GOODIX_CONTACT_SIZE;
+                error = goodix_i2c_read(ts->client,
+                                        GOODIX_READ_COOR_ADDR +
+                                                1 + GOODIX_CONTACT_SIZE,
+                                        data,
+                                        GOODIX_CONTACT_SIZE * (touch_num - 1));
+                if (error)
+                        return error;
+        }
+
+        return touch_num;
+}
+
+static void goodix_ts_report_touch(struct goodix_ts_data *ts, u8 *coor_data)
+{
+        int id = coor_data[0] & 0x0F;
+        int input_x = get_unaligned_le16(&coor_data[1]);
+        int input_y = get_unaligned_le16(&coor_data[3]);
+        int input_w = get_unaligned_le16(&coor_data[5]);
+
+        input_mt_slot(ts->input_dev, id);
+        input_mt_report_slot_state(ts->input_dev, MT_TOOL_FINGER, true);
+        input_report_abs(ts->input_dev, ABS_MT_POSITION_X, input_x);
+        input_report_abs(ts->input_dev, ABS_MT_POSITION_Y, input_y);
+        input_report_abs(ts->input_dev, ABS_MT_TOUCH_MAJOR, input_w);
+        input_report_abs(ts->input_dev, ABS_MT_WIDTH_MAJOR, input_w);
+}
+
+/**
+ * goodix_process_events - Process incoming events
+ *
+ * @ts: our goodix_ts_data pointer
+ *
+ * Called when the IRQ is triggered. Read the current device state, and push
+ * the input events to the user space.
+ */
+static void goodix_process_events(struct goodix_ts_data *ts)
+{
+        u8  point_data[1 + GOODIX_CONTACT_SIZE * GOODIX_MAX_CONTACTS];
+        int touch_num;
+        int i;
+
+        touch_num = goodix_ts_read_input_report(ts, point_data);
+        if (touch_num < 0)
+                return;
+
+        for (i = 0; i < touch_num; i++)
+                goodix_ts_report_touch(ts,
+                                &point_data[1 + GOODIX_CONTACT_SIZE * i]);
+
+        input_mt_sync_frame(ts->input_dev);
+        input_sync(ts->input_dev);
+}
+
+/**
+ * goodix_ts_irq_handler - The IRQ handler
+ *
+ * @irq: interrupt number.
+ * @dev_id: private data pointer.
+ */
+static irqreturn_t goodix_ts_irq_handler(int irq, void *dev_id)
+{
+        static const u8 end_cmd[] = {
+                GOODIX_READ_COOR_ADDR >> 8,
+                GOODIX_READ_COOR_ADDR & 0xff,
+                0
+        };
+        struct goodix_ts_data *ts = dev_id;
+
+        goodix_process_events(ts);
+
+        if (i2c_master_send(ts->client, end_cmd, sizeof(end_cmd)) < 0)
+                dev_err(&ts->client->dev, "I2C write end_cmd error\n");
+
+        return IRQ_HANDLED;
+}
+
+/**
+ * goodix_read_config - Read the embedded configuration of the panel
+ *
+ * @ts: our goodix_ts_data pointer
+ *
+ * Must be called during probe
+ */
+static void goodix_read_config(struct goodix_ts_data *ts)
+{
+        u8 config[GOODIX_CONFIG_MAX_LENGTH];
+        int error;
+
+        error = goodix_i2c_read(ts->client, GOODIX_REG_CONFIG_DATA,
+                              config,
+                           GOODIX_CONFIG_MAX_LENGTH);
+        if (error) {
+                dev_warn(&ts->client->dev,
+                         "Error reading config (%d), using defaults\n",
+                         error);
+                ts->abs_x_max = GOODIX_MAX_WIDTH;
+                ts->abs_y_max = GOODIX_MAX_HEIGHT;
+                ts->int_trigger_type = GOODIX_INT_TRIGGER;
+                return;
+        }
+
+        ts->abs_x_max = get_unaligned_le16(&config[RESOLUTION_LOC]);
+        ts->abs_y_max = get_unaligned_le16(&config[RESOLUTION_LOC + 2]);
+        ts->int_trigger_type = (config[TRIGGER_LOC]) & 0x03;
+        if (!ts->abs_x_max || !ts->abs_y_max) {
+                dev_err(&ts->client->dev,
+                        "Invalid config, using defaults\n");
+                ts->abs_x_max = GOODIX_MAX_WIDTH;
+                ts->abs_y_max = GOODIX_MAX_HEIGHT;
+        }
+}
+
+
+/**
+ * goodix_read_version - Read goodix touchscreen version
+ *
+ * @client: the i2c client
+ * @version: output buffer containing the version on success
+ */
+static int goodix_read_version(struct i2c_client *client, u16 *version)
+{
+        int error;
+        u8 buf[6];
+
+        error = goodix_i2c_read(client, GOODIX_REG_VERSION, buf, sizeof(buf));
+        if (error) {
+                dev_err(&client->dev, "read version failed: %d\n", error);
+                return error;
+        }
+
+        if (version)
+                *version = get_unaligned_le16(&buf[4]);
+
+        dev_info(&client->dev, "IC VERSION: %6ph\n", buf);
+
+        return 0;
+}
+
+/**
+ * goodix_i2c_test - I2C test function to check if the device answers.
+ *
+ * @client: the i2c client
+ */
+static int goodix_i2c_test(struct i2c_client *client)
+{
+        int retry = 0;
+        int error;
+        u8 test;
+
+        while (retry++ < 2) {
+                error = goodix_i2c_read(client, GOODIX_REG_CONFIG_DATA,
+                                        &test, 1);
+                if (!error)
+                        return 0;
+
+                dev_err(&client->dev, "i2c test failed attempt %d: %d\n",
+                        retry, error);
+                msleep(20);
+        }
+
+        return error;
+}
+
+/**
+ * goodix_request_input_dev - Allocate, populate and register the input device
+ *
+ * @ts: our goodix_ts_data pointer
+ *
+ * Must be called during probe
+ */
+static int goodix_request_input_dev(struct goodix_ts_data *ts)
+{
+        int error;
+
+        ts->input_dev = devm_input_allocate_device(&ts->client->dev);
+        if (!ts->input_dev) {
+                dev_err(&ts->client->dev, "Failed to allocate input device.");
+                return -ENOMEM;
+        }
+
+        ts->input_dev->evbit[0] = BIT_MASK(EV_SYN) |
+                                  BIT_MASK(EV_KEY) |
+                                  BIT_MASK(EV_ABS);
+
+        input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X, 0,
+                                ts->abs_x_max, 0, 0);
+        input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y, 0,
+                                ts->abs_y_max, 0, 0);
+        input_set_abs_params(ts->input_dev, ABS_MT_WIDTH_MAJOR, 0, 255, 0, 0);
+        input_set_abs_params(ts->input_dev, ABS_MT_TOUCH_MAJOR, 0, 255, 0, 0);
+
+        input_mt_init_slots(ts->input_dev, GOODIX_MAX_CONTACTS,
+                            INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+
+        ts->input_dev->name = "Goodix Capacitive TouchScreen";
+        ts->input_dev->phys = "input/ts";
+        ts->input_dev->id.bustype = BUS_I2C;
+        ts->input_dev->id.vendor = 0x0416;
+        ts->input_dev->id.product = 0x1001;
+        ts->input_dev->id.version = 10427;
+
+        error = input_register_device(ts->input_dev);
+        if (error) {
+                dev_err(&ts->client->dev,
+                        "Failed to register input device: %d", error);
+                return error;
+        }
+
+        return 0;
+}
+
+static int goodix_ts_probe(struct i2c_client *client,
+                           const struct i2c_device_id *id)
+{
+        struct goodix_ts_data *ts;
+        unsigned long irq_flags;
+        int error;
+        u16 version_info;
+
+        dev_dbg(&client->dev, "I2C Address: 0x%02x\n", client->addr);
+
+        if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+                dev_err(&client->dev, "I2C check functionality failed.\n");
+                return -ENXIO;
+        }
+
+        ts = devm_kzalloc(&client->dev, sizeof(*ts), GFP_KERNEL);
+        if (!ts)
+                return -ENOMEM;
+
+        ts->client = client;
+        i2c_set_clientdata(client, ts);
+
+        error = goodix_i2c_test(client);
+        if (error) {
+                dev_err(&client->dev, "I2C communication failure: %d\n", error);
+                return error;
+        }
+
+        error = goodix_read_version(client, &version_info);
+        if (error) {
+                dev_err(&client->dev, "Read version failed.\n");
+                return error;
+        }
+
+        goodix_read_config(ts);
+
+        error = goodix_request_input_dev(ts);
+        if (error)
+                return error;
+
+        irq_flags = goodix_irq_flags[ts->int_trigger_type] | IRQF_ONESHOT;
+        error = devm_request_threaded_irq(&ts->client->dev, client->irq,
+                                          NULL, goodix_ts_irq_handler,
+                                          irq_flags, client->name, ts);
+        if (error) {
+                dev_err(&client->dev, "request IRQ failed: %d\n", error);
+                return error;
+        }
+
+        return 0;
+}
+
+static const struct i2c_device_id goodix_ts_id[] = {
+        { "GDIX1001:00", 0 },
+        { }
+};
+
+static const struct acpi_device_id goodix_acpi_match[] = {
+        { "GDIX1001", 0 },
+        { }
+};
+MODULE_DEVICE_TABLE(acpi, goodix_acpi_match);
+
+static struct i2c_driver goodix_ts_driver = {
+        .probe = goodix_ts_probe,
+        .id_table = goodix_ts_id,
+        .driver = {
+                .name = "Goodix-TS",
+                .owner = THIS_MODULE,
+                .acpi_match_table = goodix_acpi_match,
+        },
+};
+module_i2c_driver(goodix_ts_driver);
+
+MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
+MODULE_AUTHOR("Bastien Nocera <hadess@hadess.net>");
+MODULE_DESCRIPTION("Goodix touchscreen driver");
+MODULE_LICENSE("GPL v2");