[PATCH 1/2] add driver for cypress cy8cmbr3102

From: Patrick Vogelaar
Date: Mon Feb 20 2017 - 05:34:35 EST


Signed-off-by: Patrick Vogelaar <Patrick.Vogelaar@xxxxxxxxxxxxxx>
---
drivers/input/misc/Kconfig | 12 +++
drivers/input/misc/Makefile | 1 +
drivers/input/misc/cy8cmbr3102.c | 222 +++++++++++++++++++++++++++++++++++++++
3 files changed, 235 insertions(+)
create mode 100644 drivers/input/misc/cy8cmbr3102.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 5b6c522..be3071e 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -822,4 +822,16 @@ config INPUT_HISI_POWERKEY
To compile this driver as a module, choose M here: the
module will be called hisi_powerkey.

+config INPUT_CY8CMBR3102
+ tristate "Cypress CY8CMBR3102 CapSense Express controller"
+ depends on I2C
+ select INPUT_POLLDEV
+ default n
+ help
+ Say yes here to enable support for the Cypress CY8CMBR3102
+ CapSense Express controller.
+
+ To compile this driver as a module, choose M here: the module
+ will be called cy8cmbr3102.
+
endif
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index b10523f..f9959ed 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -77,3 +77,4 @@ obj-$(CONFIG_INPUT_WM831X_ON) += wm831x-on.o
obj-$(CONFIG_INPUT_XEN_KBDDEV_FRONTEND) += xen-kbdfront.o
obj-$(CONFIG_INPUT_YEALINK) += yealink.o
obj-$(CONFIG_INPUT_IDEAPAD_SLIDEBAR) += ideapad_slidebar.o
+obj-$(CONFIG_INPUT_CY8CMBR3102) += cy8cmbr3102.o
diff --git a/drivers/input/misc/cy8cmbr3102.c b/drivers/input/misc/cy8cmbr3102.c
new file mode 100644
index 0000000..e2f5167
--- /dev/null
+++ b/drivers/input/misc/cy8cmbr3102.c
@@ -0,0 +1,222 @@
+/* Driver for Cypress CY8CMBR3102 CapSense Express Controller
+ *
+ * (C) 2017 by Gigatronik Technologies GmbH
+ * Author: Patrick Vogelaar <patrick.vogelaar@xxxxxxxxxxxxxx>
+ * All rights reserved.
+ *
+ * This code is based on mma8450.c and atmel_captouch.c.
+ *
+ * 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.
+ *
+ * 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.
+ *
+ * NOTE: This implementation does not implement the full range of functions the
+ * Cypress CY8CMBR3102 CapSense Express controller provides. It only implements
+ * its use for connected touch buttons (yet).
+ */
+
+#define DRV_VERSION "0.1"
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input-polldev.h>
+#include <linux/of.h>
+
+/* I2C Registers */
+#define CY8CMBR3102_DEVICE_ID_REG 0x90
+#define CY8CMBR3102_BUTTON_STAT 0xAA
+
+
+#define CY8CMBR3102_MAX_NUM_OF_BUTTONS 0x02
+#define CY8CMBR3102_DRV_NAME "cy8cmbr3102"
+#define CY8CMBR3102_POLL_INTERVAL 200
+#define CY8CMBR3102_POLL_INTERVAL_MAX 300
+#define CY8CMBR3102_DEVICE_ID 2561
+#define CY8CMBR3102_MAX_RETRY 5
+
+/*
+ * @i2c_client: I2C slave device client pointer
+ * @idev: Input (polled) device pointer
+ * @num_btn: Number of buttons
+ * @keycodes: map of button# to KeyCode
+ * @cy8cmbr3102_lock: mutex lock
+ */
+struct cy8cmbr3102_device {
+ struct i2c_client *client;
+ struct input_polled_dev *idev;
+ u32 num_btn;
+ u32 keycodes[CY8CMBR3102_MAX_NUM_OF_BUTTONS];
+ struct mutex cy8cmbr3102_lock;
+};
+
+static const struct i2c_device_id cy8cmbr3102_idtable[] = {
+ {"cy8cmbr3102", 0},
+ {}
+};
+MODULE_DEVICE_TABLE(i2c, cy8cmbr3102_idtable);
+
+static void cy8cmbr3102_poll(struct input_polled_dev *idev)
+{
+ struct cy8cmbr3102_device *dev = idev->private;
+ int i, ret, btn_state;
+
+ mutex_lock(&dev->cy8cmbr3102_lock);
+
+ ret = i2c_smbus_read_word_data(dev->client, CY8CMBR3102_BUTTON_STAT);
+ if (ret < 0) {
+ dev_err(&dev->client->dev, "i2c io error: %d\n", ret);
+ mutex_unlock(&dev->cy8cmbr3102_lock);
+ return;
+ }
+
+ for (i = 0; i < dev->num_btn; i++) {
+ btn_state = ret & (0x1 << i);
+ input_report_key(idev->input, dev->keycodes[i], btn_state);
+ input_sync(idev->input);
+ }
+
+ mutex_unlock(&dev->cy8cmbr3102_lock);
+}
+
+static int cy8cmbr3102_remove(struct i2c_client *client)
+{
+ struct cy8cmbr3102_device *dev = i2c_get_clientdata(client);
+ struct input_polled_dev *idev = dev->idev;
+
+ dev_dbg(&client->dev, "%s\n", __func__);
+
+ mutex_destroy(&dev->cy8cmbr3102_lock);
+ input_unregister_polled_device(idev);
+
+ return 0;
+}
+
+static int cy8cmbr3102_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct cy8cmbr3102_device *drvdata;
+ struct device *dev = &client->dev;
+ struct device_node *node;
+ int i, err, ret;
+
+ dev_dbg(&client->dev, "%s\n", __func__);
+
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE_DATA |
+ I2C_FUNC_SMBUS_WORD_DATA |
+ I2C_FUNC_SMBUS_I2C_BLOCK)) {
+ dev_err(dev, "needed i2c functionality is not supported\n");
+ return -EINVAL;
+ }
+
+ drvdata = devm_kzalloc(dev, sizeof(*drvdata), GFP_KERNEL);
+ if (!drvdata)
+ return -ENOMEM;
+
+ drvdata->client = client;
+ i2c_set_clientdata(client, drvdata);
+
+ /* device is in low-power mode and needs to be waken up */
+ for (i = 0; (i < CY8CMBR3102_MAX_RETRY) &&
+ (ret != CY8CMBR3102_DEVICE_ID); i++) {
+ ret = i2c_smbus_read_word_data(drvdata->client,
+ CY8CMBR3102_DEVICE_ID_REG);
+ dev_dbg(dev, "DEVICE_ID (%i): %i\n", i, ret);
+ }
+
+ if (ret < 0) {
+ dev_err(&client->dev, "i2c io error: %d\n", ret);
+ return -EIO;
+ } else if (ret != CY8CMBR3102_DEVICE_ID) {
+ dev_err(&client->dev, "read device ID %i is not equal to %i!\n",
+ ret, CY8CMBR3102_DEVICE_ID);
+ return -ENXIO;
+ }
+ dev_dbg(dev, "device identified by device ID\n");
+
+ drvdata->idev = devm_input_allocate_polled_device(dev);
+ if (!drvdata->idev) {
+ dev_err(dev, "failed to allocate input device\n");
+ return -ENOMEM;
+ }
+
+ node = dev->of_node;
+ if (!node) {
+ dev_err(dev, "failed to find matching node in device tree\n");
+ return -EINVAL;
+ }
+
+ if (of_property_read_bool(node, "autorepeat"))
+ __set_bit(EV_REP, drvdata->idev->input->evbit);
+
+ drvdata->num_btn = of_property_count_u32_elems(node, "linux,keycodes");
+ if (drvdata->num_btn > CY8CMBR3102_MAX_NUM_OF_BUTTONS)
+ drvdata->num_btn = CY8CMBR3102_MAX_NUM_OF_BUTTONS;
+
+ err = of_property_read_u32_array(node, "linux,keycodes",
+ drvdata->keycodes, drvdata->num_btn);
+
+ if (err) {
+ dev_err(dev, "failed to read linux,keycodes property: %d\n",
+ err);
+ return err;
+ }
+
+ for (i = 0; i < drvdata->num_btn; i++)
+ __set_bit(drvdata->keycodes[i], drvdata->idev->input->keybit);
+
+ drvdata->idev->input->id.bustype = BUS_I2C;
+ drvdata->idev->input->id.product = 0x3102;
+ drvdata->idev->input->id.version = 0;
+ drvdata->idev->input->name = CY8CMBR3102_DRV_NAME;
+ drvdata->idev->poll = cy8cmbr3102_poll;
+ drvdata->idev->poll_interval = CY8CMBR3102_POLL_INTERVAL;
+ drvdata->idev->poll_interval_max = CY8CMBR3102_POLL_INTERVAL_MAX;
+ drvdata->idev->private = drvdata;
+ drvdata->idev->input->keycode = drvdata->keycodes;
+ drvdata->idev->input->keycodemax = drvdata->num_btn;
+ drvdata->idev->input->keycodesize = sizeof(drvdata->keycodes[0]);
+ __set_bit(EV_KEY, drvdata->idev->input->evbit);
+
+ mutex_init(&drvdata->cy8cmbr3102_lock);
+
+ err = input_register_polled_device(drvdata->idev);
+ if (err)
+ return err;
+
+ dev_info(&client->dev, "chip found, driver version " DRV_VERSION "\n");
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id of_cy8cmbr3102_match[] = {
+ {.compatible = "cypress,cy8cmbr3102", },
+ {}
+};
+MODULE_DEVICE_TABLE(of, of_cy8cmbr3102_match);
+#endif
+
+static struct i2c_driver cy8cmbr3102_driver = {
+ .driver = {
+ .name = "cy8cmbr3102",
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(of_cy8cmbr3102_match),
+ },
+ .probe = cy8cmbr3102_probe,
+ .remove = cy8cmbr3102_remove,
+ .id_table = cy8cmbr3102_idtable,
+};
+module_i2c_driver(cy8cmbr3102_driver);
+
+MODULE_AUTHOR("Patrick Vogelaar <patrick.vogelaar@xxxxxxxxxxxxxx>");
+MODULE_DESCRIPTION("Cypress CY8CMBR3102 CapSense Express controller");
+MODULE_LICENSE("GPL");
+MODULE_VERSION(DRV_VERSION);
--
2.7.4