Input: add driver for Silead touchscreens
authorRobert Dolca <robert.dolca@intel.com>
Thu, 28 Jul 2016 21:28:46 +0000 (14:28 -0700)
committerDmitry Torokhov <dmitry.torokhov@gmail.com>
Wed, 3 Aug 2016 06:37:49 +0000 (23:37 -0700)
This driver adds support for Silead touchscreens. It has been tested
with GSL1680 and GSL3680 touch panels.

It supports ACPI and device tree enumeration. Screen resolution,
the maximum number of fingers supported and firmware name are
configurable.

Signed-off-by: Robert Dolca <robert.dolca@intel.com>
Signed-off-by: Daniel Jansen <djaniboe@gmail.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Documentation/devicetree/bindings/input/touchscreen/silead_gsl1680.txt [new file with mode: 0644]
drivers/input/touchscreen/Kconfig
drivers/input/touchscreen/Makefile
drivers/input/touchscreen/silead.c [new file with mode: 0644]

diff --git a/Documentation/devicetree/bindings/input/touchscreen/silead_gsl1680.txt b/Documentation/devicetree/bindings/input/touchscreen/silead_gsl1680.txt
new file mode 100644 (file)
index 0000000..1112e0d
--- /dev/null
@@ -0,0 +1,36 @@
+* GSL 1680 touchscreen controller
+
+Required properties:
+- compatible             : "silead,gsl1680"
+- reg                    : I2C slave address of the chip (0x40)
+- interrupt-parent       : a phandle pointing to the interrupt controller
+                           serving the interrupt for this chip
+- interrupts             : interrupt specification for the gsl1680 interrupt
+- power-gpios            : Specification for the pin connected to the gsl1680's
+                           shutdown input. This needs to be driven high to take the
+                           gsl1680 out of its low power state
+- touchscreen-size-x     : See touchscreen.txt
+- touchscreen-size-y     : See touchscreen.txt
+
+Optional properties:
+- touchscreen-inverted-x  : See touchscreen.txt
+- touchscreen-inverted-y  : See touchscreen.txt
+- touchscreen-swapped-x-y : See touchscreen.txt
+- silead,max-fingers     : maximum number of fingers the touchscreen can detect
+
+Example:
+
+i2c@00000000 {
+       gsl1680: touchscreen@40 {
+               compatible = "silead,gsl1680";
+               reg = <0x40>;
+               interrupt-parent = <&pio>;
+               interrupts = <6 11 IRQ_TYPE_EDGE_FALLING>;
+               power-gpios = <&pio 1 3 GPIO_ACTIVE_HIGH>;
+               touchscreen-size-x = <480>;
+               touchscreen-size-y = <800>;
+               touchscreen-inverted-x;
+               touchscreen-swapped-x-y;
+               silead,max-fingers = <5>;
+       };
+};
index ee02dc7..6abcd17 100644 (file)
@@ -1059,6 +1059,18 @@ config TOUCHSCREEN_RM_TS
          To compile this driver as a module, choose M here: the
          module will be called raydium_i2c_ts.
 
+config TOUCHSCREEN_SILEAD
+       tristate "Silead I2C touchscreen"
+       depends on I2C
+       help
+         Say Y here if you have the Silead touchscreen connected to
+         your system.
+
+         If unsure, say N.
+
+         To compile this driver as a module, choose M here: the
+         module will be called silead.
+
 config TOUCHSCREEN_ST1232
        tristate "Sitronix ST1232 touchscreen controllers"
        depends on I2C
index 3315882..3b598c9 100644 (file)
@@ -64,6 +64,7 @@ obj-$(CONFIG_TOUCHSCREEN_PENMOUNT)    += penmount.o
 obj-$(CONFIG_TOUCHSCREEN_PIXCIR)       += pixcir_i2c_ts.o
 obj-$(CONFIG_TOUCHSCREEN_RM_TS)                += raydium_i2c_ts.o
 obj-$(CONFIG_TOUCHSCREEN_S3C2410)      += s3c2410_ts.o
+obj-$(CONFIG_TOUCHSCREEN_SILEAD)       += silead.o
 obj-$(CONFIG_TOUCHSCREEN_ST1232)       += st1232.o
 obj-$(CONFIG_TOUCHSCREEN_STMPE)                += stmpe-ts.o
 obj-$(CONFIG_TOUCHSCREEN_SUN4I)                += sun4i-ts.o
diff --git a/drivers/input/touchscreen/silead.c b/drivers/input/touchscreen/silead.c
new file mode 100644 (file)
index 0000000..5f55167
--- /dev/null
@@ -0,0 +1,568 @@
+/* -------------------------------------------------------------------------
+ * Copyright (C) 2014-2015, Intel Corporation
+ *
+ * Derived from:
+ *  gslX68X.c
+ *  Copyright (C) 2010-2015, Shanghai Sileadinc Co.Ltd
+ *
+ *  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; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  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.
+ * -------------------------------------------------------------------------
+ */
+
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/acpi.h>
+#include <linux/interrupt.h>
+#include <linux/gpio/consumer.h>
+#include <linux/delay.h>
+#include <linux/firmware.h>
+#include <linux/input.h>
+#include <linux/input/mt.h>
+#include <linux/input/touchscreen.h>
+#include <linux/pm.h>
+#include <linux/irq.h>
+
+#include <asm/unaligned.h>
+
+#define SILEAD_TS_NAME         "silead_ts"
+
+#define SILEAD_REG_RESET       0xE0
+#define SILEAD_REG_DATA                0x80
+#define SILEAD_REG_TOUCH_NR    0x80
+#define SILEAD_REG_POWER       0xBC
+#define SILEAD_REG_CLOCK       0xE4
+#define SILEAD_REG_STATUS      0xB0
+#define SILEAD_REG_ID          0xFC
+#define SILEAD_REG_MEM_CHECK   0xB0
+
+#define SILEAD_STATUS_OK       0x5A5A5A5A
+#define SILEAD_TS_DATA_LEN     44
+#define SILEAD_CLOCK           0x04
+
+#define SILEAD_CMD_RESET       0x88
+#define SILEAD_CMD_START       0x00
+
+#define SILEAD_POINT_DATA_LEN  0x04
+#define SILEAD_POINT_Y_OFF      0x00
+#define SILEAD_POINT_Y_MSB_OFF 0x01
+#define SILEAD_POINT_X_OFF     0x02
+#define SILEAD_POINT_X_MSB_OFF 0x03
+#define SILEAD_TOUCH_ID_MASK   0xF0
+
+#define SILEAD_CMD_SLEEP_MIN   10000
+#define SILEAD_CMD_SLEEP_MAX   20000
+#define SILEAD_POWER_SLEEP     20
+#define SILEAD_STARTUP_SLEEP   30
+
+#define SILEAD_MAX_FINGERS     10
+
+enum silead_ts_power {
+       SILEAD_POWER_ON  = 1,
+       SILEAD_POWER_OFF = 0
+};
+
+struct silead_ts_data {
+       struct i2c_client *client;
+       struct gpio_desc *gpio_power;
+       struct input_dev *input;
+       char fw_name[64];
+       struct touchscreen_properties prop;
+       u32 max_fingers;
+       u32 chip_id;
+       struct input_mt_pos pos[SILEAD_MAX_FINGERS];
+       int slots[SILEAD_MAX_FINGERS];
+       int id[SILEAD_MAX_FINGERS];
+};
+
+struct silead_fw_data {
+       u32 offset;
+       u32 val;
+};
+
+static int silead_ts_request_input_dev(struct silead_ts_data *data)
+{
+       struct device *dev = &data->client->dev;
+       int error;
+
+       data->input = devm_input_allocate_device(dev);
+       if (!data->input) {
+               dev_err(dev,
+                       "Failed to allocate input device\n");
+               return -ENOMEM;
+       }
+
+       input_set_abs_params(data->input, ABS_MT_POSITION_X, 0, 4095, 0, 0);
+       input_set_abs_params(data->input, ABS_MT_POSITION_Y, 0, 4095, 0, 0);
+       touchscreen_parse_properties(data->input, true, &data->prop);
+
+       input_mt_init_slots(data->input, data->max_fingers,
+                           INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED |
+                           INPUT_MT_TRACK);
+
+       data->input->name = SILEAD_TS_NAME;
+       data->input->phys = "input/ts";
+       data->input->id.bustype = BUS_I2C;
+
+       error = input_register_device(data->input);
+       if (error) {
+               dev_err(dev, "Failed to register input device: %d\n", error);
+               return error;
+       }
+
+       return 0;
+}
+
+static void silead_ts_set_power(struct i2c_client *client,
+                               enum silead_ts_power state)
+{
+       struct silead_ts_data *data = i2c_get_clientdata(client);
+
+       if (data->gpio_power) {
+               gpiod_set_value_cansleep(data->gpio_power, state);
+               msleep(SILEAD_POWER_SLEEP);
+       }
+}
+
+static void silead_ts_read_data(struct i2c_client *client)
+{
+       struct silead_ts_data *data = i2c_get_clientdata(client);
+       struct input_dev *input = data->input;
+       struct device *dev = &client->dev;
+       u8 *bufp, buf[SILEAD_TS_DATA_LEN];
+       int touch_nr, error, i;
+
+       error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_DATA,
+                                             SILEAD_TS_DATA_LEN, buf);
+       if (error < 0) {
+               dev_err(dev, "Data read error %d\n", error);
+               return;
+       }
+
+       touch_nr = buf[0];
+       if (touch_nr < 0)
+               return;
+
+       if (touch_nr > data->max_fingers) {
+               dev_warn(dev, "More touches reported then supported %d > %d\n",
+                        touch_nr, data->max_fingers);
+               touch_nr = data->max_fingers;
+       }
+
+       bufp = buf + SILEAD_POINT_DATA_LEN;
+       for (i = 0; i < touch_nr; i++, bufp += SILEAD_POINT_DATA_LEN) {
+               /* Bits 4-7 are the touch id */
+               data->id[i] = (bufp[SILEAD_POINT_X_MSB_OFF] &
+                              SILEAD_TOUCH_ID_MASK) >> 4;
+               touchscreen_set_mt_pos(&data->pos[i], &data->prop,
+                       get_unaligned_le16(&bufp[SILEAD_POINT_X_OFF]) & 0xfff,
+                       get_unaligned_le16(&bufp[SILEAD_POINT_Y_OFF]) & 0xfff);
+       }
+
+       input_mt_assign_slots(input, data->slots, data->pos, touch_nr, 0);
+
+       for (i = 0; i < touch_nr; i++) {
+               input_mt_slot(input, data->slots[i]);
+               input_mt_report_slot_state(input, MT_TOOL_FINGER, true);
+               input_report_abs(input, ABS_MT_POSITION_X, data->pos[i].x);
+               input_report_abs(input, ABS_MT_POSITION_Y, data->pos[i].y);
+
+               dev_dbg(dev, "x=%d y=%d hw_id=%d sw_id=%d\n", data->pos[i].x,
+                       data->pos[i].y, data->id[i], data->slots[i]);
+       }
+
+       input_mt_sync_frame(input);
+       input_sync(input);
+}
+
+static int silead_ts_init(struct i2c_client *client)
+{
+       struct silead_ts_data *data = i2c_get_clientdata(client);
+       int error;
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
+                                         SILEAD_CMD_RESET);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_TOUCH_NR,
+                                       data->max_fingers);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
+                                         SILEAD_CLOCK);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
+                                         SILEAD_CMD_START);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       return 0;
+
+i2c_write_err:
+       dev_err(&client->dev, "Registers clear error %d\n", error);
+       return error;
+}
+
+static int silead_ts_reset(struct i2c_client *client)
+{
+       int error;
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET,
+                                         SILEAD_CMD_RESET);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_CLOCK,
+                                         SILEAD_CLOCK);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_POWER,
+                                         SILEAD_CMD_START);
+       if (error)
+               goto i2c_write_err;
+       usleep_range(SILEAD_CMD_SLEEP_MIN, SILEAD_CMD_SLEEP_MAX);
+
+       return 0;
+
+i2c_write_err:
+       dev_err(&client->dev, "Chip reset error %d\n", error);
+       return error;
+}
+
+static int silead_ts_startup(struct i2c_client *client)
+{
+       int error;
+
+       error = i2c_smbus_write_byte_data(client, SILEAD_REG_RESET, 0x00);
+       if (error) {
+               dev_err(&client->dev, "Startup error %d\n", error);
+               return error;
+       }
+
+       msleep(SILEAD_STARTUP_SLEEP);
+
+       return 0;
+}
+
+static int silead_ts_load_fw(struct i2c_client *client)
+{
+       struct device *dev = &client->dev;
+       struct silead_ts_data *data = i2c_get_clientdata(client);
+       unsigned int fw_size, i;
+       const struct firmware *fw;
+       struct silead_fw_data *fw_data;
+       int error;
+
+       dev_dbg(dev, "Firmware file name: %s", data->fw_name);
+
+       error = request_firmware(&fw, data->fw_name, dev);
+       if (error) {
+               dev_err(dev, "Firmware request error %d\n", error);
+               return error;
+       }
+
+       fw_size = fw->size / sizeof(*fw_data);
+       fw_data = (struct silead_fw_data *)fw->data;
+
+       for (i = 0; i < fw_size; i++) {
+               error = i2c_smbus_write_i2c_block_data(client,
+                                                      fw_data[i].offset,
+                                                      4,
+                                                      (u8 *)&fw_data[i].val);
+               if (error) {
+                       dev_err(dev, "Firmware load error %d\n", error);
+                       break;
+               }
+       }
+
+       release_firmware(fw);
+       return error ?: 0;
+}
+
+static u32 silead_ts_get_status(struct i2c_client *client)
+{
+       int error;
+       __le32 status;
+
+       error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_STATUS,
+                                             sizeof(status), (u8 *)&status);
+       if (error < 0) {
+               dev_err(&client->dev, "Status read error %d\n", error);
+               return error;
+       }
+
+       return le32_to_cpu(status);
+}
+
+static int silead_ts_get_id(struct i2c_client *client)
+{
+       struct silead_ts_data *data = i2c_get_clientdata(client);
+       __le32 chip_id;
+       int error;
+
+       error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_ID,
+                                             sizeof(chip_id), (u8 *)&chip_id);
+       if (error < 0) {
+               dev_err(&client->dev, "Chip ID read error %d\n", error);
+               return error;
+       }
+
+       data->chip_id = le32_to_cpu(chip_id);
+       dev_info(&client->dev, "Silead chip ID: 0x%8X", data->chip_id);
+
+       return 0;
+}
+
+static int silead_ts_setup(struct i2c_client *client)
+{
+       int error;
+       u32 status;
+
+       silead_ts_set_power(client, SILEAD_POWER_OFF);
+       silead_ts_set_power(client, SILEAD_POWER_ON);
+
+       error = silead_ts_get_id(client);
+       if (error)
+               return error;
+
+       error = silead_ts_init(client);
+       if (error)
+               return error;
+
+       error = silead_ts_reset(client);
+       if (error)
+               return error;
+
+       error = silead_ts_load_fw(client);
+       if (error)
+               return error;
+
+       error = silead_ts_startup(client);
+       if (error)
+               return error;
+
+       status = silead_ts_get_status(client);
+       if (status != SILEAD_STATUS_OK) {
+               dev_err(&client->dev,
+                       "Initialization error, status: 0x%X\n", status);
+               return -ENODEV;
+       }
+
+       return 0;
+}
+
+static irqreturn_t silead_ts_threaded_irq_handler(int irq, void *id)
+{
+       struct silead_ts_data *data = id;
+       struct i2c_client *client = data->client;
+
+       silead_ts_read_data(client);
+
+       return IRQ_HANDLED;
+}
+
+static void silead_ts_read_props(struct i2c_client *client)
+{
+       struct silead_ts_data *data = i2c_get_clientdata(client);
+       struct device *dev = &client->dev;
+       const char *str;
+       int error;
+
+       error = device_property_read_u32(dev, "silead,max-fingers",
+                                        &data->max_fingers);
+       if (error) {
+               dev_dbg(dev, "Max fingers read error %d\n", error);
+               data->max_fingers = 5; /* Most devices handle up-to 5 fingers */
+       }
+
+       error = device_property_read_string(dev, "touchscreen-fw-name", &str);
+       if (!error)
+               snprintf(data->fw_name, sizeof(data->fw_name), "%s", str);
+       else
+               dev_dbg(dev, "Firmware file name read error. Using default.");
+}
+
+#ifdef CONFIG_ACPI
+static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
+                                        const struct i2c_device_id *id)
+{
+       const struct acpi_device_id *acpi_id;
+       struct device *dev = &data->client->dev;
+       int i;
+
+       if (ACPI_HANDLE(dev)) {
+               acpi_id = acpi_match_device(dev->driver->acpi_match_table, dev);
+               if (!acpi_id)
+                       return -ENODEV;
+
+               snprintf(data->fw_name, sizeof(data->fw_name), "%s.fw",
+                       acpi_id->id);
+
+               for (i = 0; i < strlen(data->fw_name); i++)
+                       data->fw_name[i] = tolower(data->fw_name[i]);
+       } else {
+               snprintf(data->fw_name, sizeof(data->fw_name), "%s.fw",
+                       id->name);
+       }
+
+       return 0;
+}
+#else
+static int silead_ts_set_default_fw_name(struct silead_ts_data *data,
+                                        const struct i2c_device_id *id)
+{
+       snprintf(data->fw_name, sizeof(data->fw_name), "%s.fw", id->name);
+       return 0;
+}
+#endif
+
+static int silead_ts_probe(struct i2c_client *client,
+                          const struct i2c_device_id *id)
+{
+       struct silead_ts_data *data;
+       struct device *dev = &client->dev;
+       int error;
+
+       if (!i2c_check_functionality(client->adapter,
+                                    I2C_FUNC_I2C |
+                                    I2C_FUNC_SMBUS_READ_I2C_BLOCK |
+                                    I2C_FUNC_SMBUS_WRITE_I2C_BLOCK)) {
+               dev_err(dev, "I2C functionality check failed\n");
+               return -ENXIO;
+       }
+
+       data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
+       if (!data)
+               return -ENOMEM;
+
+       i2c_set_clientdata(client, data);
+       data->client = client;
+
+       error = silead_ts_set_default_fw_name(data, id);
+       if (error)
+               return error;
+
+       silead_ts_read_props(client);
+
+       /* We must have the IRQ provided by DT or ACPI subsytem */
+       if (client->irq <= 0)
+               return -ENODEV;
+
+       /* Power GPIO pin */
+       data->gpio_power = gpiod_get_optional(dev, "power", GPIOD_OUT_LOW);
+       if (IS_ERR(data->gpio_power)) {
+               if (PTR_ERR(data->gpio_power) != -EPROBE_DEFER)
+                       dev_err(dev, "Shutdown GPIO request failed\n");
+               return PTR_ERR(data->gpio_power);
+       }
+
+       error = silead_ts_setup(client);
+       if (error)
+               return error;
+
+       error = silead_ts_request_input_dev(data);
+       if (error)
+               return error;
+
+       error = devm_request_threaded_irq(dev, client->irq,
+                                         NULL, silead_ts_threaded_irq_handler,
+                                         IRQF_ONESHOT, client->name, data);
+       if (error) {
+               if (error != -EPROBE_DEFER)
+                       dev_err(dev, "IRQ request failed %d\n", error);
+               return error;
+       }
+
+       return 0;
+}
+
+static int __maybe_unused silead_ts_suspend(struct device *dev)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+
+       silead_ts_set_power(client, SILEAD_POWER_OFF);
+       return 0;
+}
+
+static int __maybe_unused silead_ts_resume(struct device *dev)
+{
+       struct i2c_client *client = to_i2c_client(dev);
+       int error, status;
+
+       silead_ts_set_power(client, SILEAD_POWER_ON);
+
+       error = silead_ts_reset(client);
+       if (error)
+               return error;
+
+       error = silead_ts_startup(client);
+       if (error)
+               return error;
+
+       status = silead_ts_get_status(client);
+       if (status != SILEAD_STATUS_OK) {
+               dev_err(dev, "Resume error, status: 0x%02x\n", status);
+               return -ENODEV;
+       }
+
+       return 0;
+}
+
+static SIMPLE_DEV_PM_OPS(silead_ts_pm, silead_ts_suspend, silead_ts_resume);
+
+static const struct i2c_device_id silead_ts_id[] = {
+       { "gsl1680", 0 },
+       { "gsl1688", 0 },
+       { "gsl3670", 0 },
+       { "gsl3675", 0 },
+       { "gsl3692", 0 },
+       { "mssl1680", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, silead_ts_id);
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id silead_ts_acpi_match[] = {
+       { "GSL1680", 0 },
+       { "GSL1688", 0 },
+       { "GSL3670", 0 },
+       { "GSL3675", 0 },
+       { "GSL3692", 0 },
+       { "MSSL1680", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(acpi, silead_ts_acpi_match);
+#endif
+
+static struct i2c_driver silead_ts_driver = {
+       .probe = silead_ts_probe,
+       .id_table = silead_ts_id,
+       .driver = {
+               .name = SILEAD_TS_NAME,
+               .acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
+               .pm = &silead_ts_pm,
+       },
+};
+module_i2c_driver(silead_ts_driver);
+
+MODULE_AUTHOR("Robert Dolca <robert.dolca@intel.com>");
+MODULE_DESCRIPTION("Silead I2C touchscreen driver");
+MODULE_LICENSE("GPL");