2015-07-22 17:25:29

by Robert Dolca

[permalink] [raw]
Subject: [PATCH v2] Add generic driver for Silead tochscreens

This driver adds support for Silead touchscreens. It has been tested
with GSL1680 and GSL3680 touch panels.

It supports ACPI and device tree enumeration. For ACPI you need ACPI 5.1+
in order to be able to use named GPIOs. In device tree you can use
'interrupts' or a named GPIO for IRQ.

Screen resolution, the maximum number of fingers supported and firmware
name are configurable using ACPI/DT properties.

Signed-off-by: Robert Dolca <[email protected]>
---
Changes since v1
- changed device tree properties names
- removed cast for `void *id`
- removed ifdef from suspend and resume and use __maybe_unused
- remove ifdef from ACPI_PTR
- renamed ret to error
- removed input_set_capability for EV_ABS
- fixed endianess issues
- added mask for y in order to use only 12 bits
- using the 4 MSb for touch ID instead of LSb (bug)
- using the 4 LSB for X instead of MSb (bug)
- removed finger id reporting (3692 and 1680 models send 0 for all fingers)
I will investigate with other models

drivers/input/touchscreen/Kconfig | 12 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/silead.c | 602 +++++++++++++++++++++++++++++++++++++
3 files changed, 615 insertions(+)
create mode 100644 drivers/input/touchscreen/silead.c

diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 2046633..4fff247 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -373,6 +373,18 @@ config TOUCHSCREEN_S3C2410
To compile this driver as a module, choose M here: the
module will be called s3c2410_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_GUNZE
tristate "Gunze AHL-51S touchscreen"
select SERIO
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 44deea7..328ec81 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -58,6 +58,7 @@ obj-$(CONFIG_TOUCHSCREEN_PCAP) += pcap_ts.o
obj-$(CONFIG_TOUCHSCREEN_PENMOUNT) += penmount.o
obj-$(CONFIG_TOUCHSCREEN_PIXCIR) += pixcir_i2c_ts.o
obj-$(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
index 0000000..36db3d2
--- /dev/null
+++ b/drivers/input/touchscreen/silead.c
@@ -0,0 +1,602 @@
+/* -------------------------------------------------------------------------
+ * 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/pm.h>
+#include <linux/irq.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_POINT_HSB_MASK 0x0F
+#define SILEAD_TOUCH_ID_MASK 0xF0
+
+#define SILEAD_DP_X_MAX "touchscreen-size-x"
+#define SILEAD_DP_Y_MAX "touchscreen-size-y"
+#define SILEAD_DP_MAX_FINGERS "touchscreen-max-fingers"
+#define SILEAD_DP_FW_NAME "touchscreen-fw-name"
+#define SILEAD_PWR_GPIO_NAME "power"
+
+#define SILEAD_CMD_SLEEP_MIN 10000
+#define SILEAD_CMD_SLEEP_MAX 20000
+#define SILEAD_POWER_SLEEP 20
+#define SILEAD_STARTUP_SLEEP 30
+
+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;
+ const char *custom_fw_name;
+ char fw_name[I2C_NAME_SIZE];
+ u16 x_max;
+ u16 y_max;
+ u8 max_fingers;
+ u32 chip_id;
+};
+
+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,
+ data->x_max, 0, 0);
+ input_set_abs_params(data->input, ABS_MT_POSITION_Y, 0,
+ data->y_max, 0, 0);
+
+ input_mt_init_slots(data->input, data->max_fingers,
+ INPUT_MT_DIRECT | INPUT_MT_DROP_UNUSED);
+
+ 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_report_touch(struct silead_ts_data *data, u16 x, u16 y,
+ u8 id)
+{
+ input_mt_slot(data->input, id);
+ input_mt_report_slot_state(data->input, MT_TOOL_FINGER, true);
+ input_report_abs(data->input, ABS_MT_POSITION_X, x);
+ input_report_abs(data->input, ABS_MT_POSITION_Y, y);
+}
+
+static void silead_ts_set_power(struct i2c_client *client,
+ enum silead_ts_power state)
+{
+ struct silead_ts_data *data = i2c_get_clientdata(client);
+
+ 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 device *dev = &client->dev;
+ u8 buf[SILEAD_TS_DATA_LEN];
+ int x, y, id, touch_nr, error, i, offset;
+
+ 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;
+
+ dev_dbg(dev, "Touch number: %d\n", touch_nr);
+
+ for (i = 1; i <= touch_nr; i++) {
+ offset = i * SILEAD_POINT_DATA_LEN;
+
+ /* Bits 4-7 are the touch id */
+ id = (buf[offset + SILEAD_POINT_X_MSB_OFF] &
+ SILEAD_TOUCH_ID_MASK) >> 4;
+
+ /* Bits 0-3 are MSB of X */
+ buf[offset + SILEAD_POINT_X_MSB_OFF] =
+ buf[offset + SILEAD_POINT_X_MSB_OFF] &
+ SILEAD_POINT_HSB_MASK;
+
+ /* Bits 0-3 are MSB of Y */
+ buf[offset + SILEAD_POINT_Y_MSB_OFF] =
+ buf[offset + SILEAD_POINT_Y_MSB_OFF] &
+ SILEAD_POINT_HSB_MASK;
+
+ y = le16_to_cpup((__le16 *)(buf + offset + SILEAD_POINT_Y_OFF));
+ x = le16_to_cpup((__le16 *)(buf + offset + SILEAD_POINT_X_OFF));
+
+ dev_dbg(dev, "x=%d y=%d id=%d\n", x, y, id);
+ silead_ts_report_touch(data, x, y, id);
+ }
+
+ input_mt_sync_frame(data->input);
+ input_sync(data->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);
+
+ if (data->custom_fw_name)
+ error = request_firmware(&fw, data->custom_fw_name, dev);
+ else
+ 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);
+ goto release_fw_err;
+ }
+ }
+
+ release_firmware(fw);
+ return 0;
+
+release_fw_err:
+ release_firmware(fw);
+ return error;
+}
+
+static u32 silead_ts_get_status(struct i2c_client *client)
+{
+ int error;
+ u32 status;
+
+ error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_STATUS, 4,
+ (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);
+ int error;
+
+ error = i2c_smbus_read_i2c_block_data(client, SILEAD_REG_ID, 4,
+ (u8 *)&data->chip_id);
+
+ data->chip_id = le32_to_cpu(data->chip_id);
+
+ if (error < 0) {
+ dev_err(&client->dev, "Chip ID read error %d\n", error);
+ return error;
+ }
+
+ return 0;
+}
+
+static int silead_ts_setup(struct i2c_client *client)
+{
+ struct silead_ts_data *data = i2c_get_clientdata(client);
+ struct device *dev = &client->dev;
+ 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;
+ dev_dbg(dev, "Chip ID: 0x%8X", data->chip_id);
+
+ 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(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 int silead_ts_read_props(struct i2c_client *client)
+{
+ struct silead_ts_data *data = i2c_get_clientdata(client);
+ struct device *dev = &client->dev;
+ int error;
+
+ error = device_property_read_u16(dev, SILEAD_DP_X_MAX, &data->x_max);
+ if (error) {
+ dev_err(dev, "Resolution X read error %d\n", error);
+ goto error;
+ }
+
+ error = device_property_read_u16(dev, SILEAD_DP_Y_MAX, &data->y_max);
+ if (error) {
+ dev_err(dev, "Resolution Y read error %d\n", error);
+ goto error;
+ }
+
+ error = device_property_read_u8(dev, SILEAD_DP_MAX_FINGERS,
+ &data->max_fingers);
+ if (error) {
+ dev_err(dev, "Max fingers read error %d\n", error);
+ goto error;
+ }
+
+ error = device_property_read_string(dev, SILEAD_DP_FW_NAME,
+ &data->custom_fw_name);
+ if (error)
+ dev_info(dev, "Firmware file name read error. Using default.");
+
+ dev_dbg(dev, "X max = %d, Y max = %d, max fingers = %d",
+ data->x_max, data->y_max, data->max_fingers);
+
+ return 0;
+
+error:
+ return error;
+}
+
+#ifdef CONFIG_ACPI
+static const struct acpi_device_id silead_ts_acpi_match[];
+
+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(silead_ts_acpi_match, dev);
+ if (!acpi_id)
+ return -ENODEV;
+
+ sprintf(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 {
+ sprintf(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)
+{
+ sprintf(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;
+
+ /* If the IRQ is not filled by DT or ACPI subsytem
+ * we can't continue without it */
+ if (client->irq <= 0)
+ return -ENODEV;
+
+ /* Power GPIO pin */
+ data->gpio_power = devm_gpiod_get(dev, SILEAD_PWR_GPIO_NAME,
+ GPIOD_OUT_LOW);
+ if (IS_ERR(data->gpio_power)) {
+ dev_err(dev, "Shutdown GPIO request failed\n");
+ return PTR_ERR(data->gpio_power);
+ }
+
+ error = silead_ts_read_props(client);
+ if (error)
+ return error;
+
+ 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 | IRQ_TYPE_EDGE_RISING,
+ client->name, data);
+ if (error) {
+ dev_err(dev, "IRQ request failed %d\n", error);
+ return error;
+ }
+
+ dev_dbg(dev, "Probing succeded\n");
+ 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%X\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 },
+ { }
+};
+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 },
+ { }
+};
+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,
+ .owner = THIS_MODULE,
+ .acpi_match_table = ACPI_PTR(silead_ts_acpi_match),
+ .pm = &silead_ts_pm,
+ },
+};
+module_i2c_driver(silead_ts_driver);
+
+MODULE_AUTHOR("Robert Dolca <[email protected]>");
+MODULE_DESCRIPTION("Silead I2C touchscreen driver");
+MODULE_LICENSE("GPL");
--
1.9.1