--- /dev/null
+/*
+ * Driver for TCA8418 I2C keyboard
+ *
+ * Copyright (C) 2011 Fuel7, Inc. All rights reserved.
+ *
+ * Author: Kyle Manna <kyle.manna@fuel7.com>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public
+ * License v2 as published by the Free Software Foundation.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public
+ * License along with this program; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 021110-1307, USA.
+ *
+ * If you can't comply with GPLv2, alternative licensing terms may be
+ * arranged. Please contact Fuel7, Inc. (http://fuel7.com/) for proprietary
+ * alternative licensing inquiries.
+ */
+
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/delay.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/workqueue.h>
+#include <linux/gpio.h>
+#include <linux/i2c.h>
+#include <linux/input.h>
+#include <linux/input/tca8418_keypad.h>
+#include <linux/of.h>
+
+/* TCA8418 hardware limits */
+#define TCA8418_MAX_ROWS 8
+#define TCA8418_MAX_COLS 10
+
+/* TCA8418 register offsets */
+#define REG_CFG 0x01
+#define REG_INT_STAT 0x02
+#define REG_KEY_LCK_EC 0x03
+#define REG_KEY_EVENT_A 0x04
+#define REG_KEY_EVENT_B 0x05
+#define REG_KEY_EVENT_C 0x06
+#define REG_KEY_EVENT_D 0x07
+#define REG_KEY_EVENT_E 0x08
+#define REG_KEY_EVENT_F 0x09
+#define REG_KEY_EVENT_G 0x0A
+#define REG_KEY_EVENT_H 0x0B
+#define REG_KEY_EVENT_I 0x0C
+#define REG_KEY_EVENT_J 0x0D
+#define REG_KP_LCK_TIMER 0x0E
+#define REG_UNLOCK1 0x0F
+#define REG_UNLOCK2 0x10
+#define REG_GPIO_INT_STAT1 0x11
+#define REG_GPIO_INT_STAT2 0x12
+#define REG_GPIO_INT_STAT3 0x13
+#define REG_GPIO_DAT_STAT1 0x14
+#define REG_GPIO_DAT_STAT2 0x15
+#define REG_GPIO_DAT_STAT3 0x16
+#define REG_GPIO_DAT_OUT1 0x17
+#define REG_GPIO_DAT_OUT2 0x18
+#define REG_GPIO_DAT_OUT3 0x19
+#define REG_GPIO_INT_EN1 0x1A
+#define REG_GPIO_INT_EN2 0x1B
+#define REG_GPIO_INT_EN3 0x1C
+#define REG_KP_GPIO1 0x1D
+#define REG_KP_GPIO2 0x1E
+#define REG_KP_GPIO3 0x1F
+#define REG_GPI_EM1 0x20
+#define REG_GPI_EM2 0x21
+#define REG_GPI_EM3 0x22
+#define REG_GPIO_DIR1 0x23
+#define REG_GPIO_DIR2 0x24
+#define REG_GPIO_DIR3 0x25
+#define REG_GPIO_INT_LVL1 0x26
+#define REG_GPIO_INT_LVL2 0x27
+#define REG_GPIO_INT_LVL3 0x28
+#define REG_DEBOUNCE_DIS1 0x29
+#define REG_DEBOUNCE_DIS2 0x2A
+#define REG_DEBOUNCE_DIS3 0x2B
+#define REG_GPIO_PULL1 0x2C
+#define REG_GPIO_PULL2 0x2D
+#define REG_GPIO_PULL3 0x2E
+
+/* TCA8418 bit definitions */
+#define CFG_AI BIT(7)
+#define CFG_GPI_E_CFG BIT(6)
+#define CFG_OVR_FLOW_M BIT(5)
+#define CFG_INT_CFG BIT(4)
+#define CFG_OVR_FLOW_IEN BIT(3)
+#define CFG_K_LCK_IEN BIT(2)
+#define CFG_GPI_IEN BIT(1)
+#define CFG_KE_IEN BIT(0)
+
+#define INT_STAT_CAD_INT BIT(4)
+#define INT_STAT_OVR_FLOW_INT BIT(3)
+#define INT_STAT_K_LCK_INT BIT(2)
+#define INT_STAT_GPI_INT BIT(1)
+#define INT_STAT_K_INT BIT(0)
+
+/* TCA8418 register masks */
+#define KEY_LCK_EC_KEC 0x7
+#define KEY_EVENT_CODE 0x7f
+#define KEY_EVENT_VALUE 0x80
+
+struct tca8418_keypad {
+ struct i2c_client *client;
+ struct input_dev *input;
+
+ unsigned int row_shift;
+};
+
+/*
+ * Write a byte to the TCA8418
+ */
+static int tca8418_write_byte(struct tca8418_keypad *keypad_data,
+ int reg, u8 val)
+{
+ int error;
+
+ error = i2c_smbus_write_byte_data(keypad_data->client, reg, val);
+ if (error < 0) {
+ dev_err(&keypad_data->client->dev,
+ "%s failed, reg: %d, val: %d, error: %d\n",
+ __func__, reg, val, error);
+ return error;
+ }
+
+ return 0;
+}
+
+/*
+ * Read a byte from the TCA8418
+ */
+static int tca8418_read_byte(struct tca8418_keypad *keypad_data,
+ int reg, u8 *val)
+{
+ int error;
+
+ error = i2c_smbus_read_byte_data(keypad_data->client, reg);
+ if (error < 0) {
+ dev_err(&keypad_data->client->dev,
+ "%s failed, reg: %d, error: %d\n",
+ __func__, reg, error);
+ return error;
+ }
+
+ *val = (u8)error;
+
+ return 0;
+}
+
+static void tca8418_read_keypad(struct tca8418_keypad *keypad_data)
+{
+ struct input_dev *input = keypad_data->input;
+ unsigned short *keymap = input->keycode;
+ int error, col, row;
+ u8 reg, state, code;
+
+ /* Initial read of the key event FIFO */
+ error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, ®);
+
+ /* Assume that key code 0 signifies empty FIFO */
+ while (error >= 0 && reg > 0) {
+ state = reg & KEY_EVENT_VALUE;
+ code = reg & KEY_EVENT_CODE;
+
+ row = code / TCA8418_MAX_COLS;
+ col = code % TCA8418_MAX_COLS;
+
+ row = (col) ? row : row - 1;
+ col = (col) ? col - 1 : TCA8418_MAX_COLS - 1;
+
+ code = MATRIX_SCAN_CODE(row, col, keypad_data->row_shift);
+ input_event(input, EV_MSC, MSC_SCAN, code);
+ input_report_key(input, keymap[code], state);
+
+ /* Read for next loop */
+ error = tca8418_read_byte(keypad_data, REG_KEY_EVENT_A, ®);
+ }
+
+ if (error < 0)
+ dev_err(&keypad_data->client->dev,
+ "unable to read REG_KEY_EVENT_A\n");
+
+ input_sync(input);
+}
+
+/*
+ * Threaded IRQ handler and this can (and will) sleep.
+ */
+static irqreturn_t tca8418_irq_handler(int irq, void *dev_id)
+{
+ struct tca8418_keypad *keypad_data = dev_id;
+ u8 reg;
+ int error;
+
+ error = tca8418_read_byte(keypad_data, REG_INT_STAT, ®);
+ if (error) {
+ dev_err(&keypad_data->client->dev,
+ "unable to read REG_INT_STAT\n");
+ return IRQ_NONE;
+ }
+
+ if (!reg)
+ return IRQ_NONE;
+
+ if (reg & INT_STAT_OVR_FLOW_INT)
+ dev_warn(&keypad_data->client->dev, "overflow occurred\n");
+
+ if (reg & INT_STAT_K_INT)
+ tca8418_read_keypad(keypad_data);
+
+ /* Clear all interrupts, even IRQs we didn't check (GPI, CAD, LCK) */
+ reg = 0xff;
+ error = tca8418_write_byte(keypad_data, REG_INT_STAT, reg);
+ if (error)
+ dev_err(&keypad_data->client->dev,
+ "unable to clear REG_INT_STAT\n");
+
+ return IRQ_HANDLED;
+}
+
+/*
+ * Configure the TCA8418 for keypad operation
+ */
+static int tca8418_configure(struct tca8418_keypad *keypad_data,
+ u32 rows, u32 cols)
+{
+ int reg, error;
+
+ /* Write config register, if this fails assume device not present */
+ error = tca8418_write_byte(keypad_data, REG_CFG,
+ CFG_INT_CFG | CFG_OVR_FLOW_IEN | CFG_KE_IEN);
+ if (error < 0)
+ return -ENODEV;
+
+
+ /* Assemble a mask for row and column registers */
+ reg = ~(~0 << rows);
+ reg += (~(~0 << cols)) << 8;
+
+ /* Set registers to keypad mode */
+ error |= tca8418_write_byte(keypad_data, REG_KP_GPIO1, reg);
+ error |= tca8418_write_byte(keypad_data, REG_KP_GPIO2, reg >> 8);
+ error |= tca8418_write_byte(keypad_data, REG_KP_GPIO3, reg >> 16);
+
+ /* Enable column debouncing */
+ error |= tca8418_write_byte(keypad_data, REG_DEBOUNCE_DIS1, reg);
+ error |= tca8418_write_byte(keypad_data, REG_DEBOUNCE_DIS2, reg >> 8);
+ error |= tca8418_write_byte(keypad_data, REG_DEBOUNCE_DIS3, reg >> 16);
+
+ return error;
+}
+
+static int tca8418_keypad_probe(struct i2c_client *client,
+ const struct i2c_device_id *id)
+{
+ struct device *dev = &client->dev;
+ const struct tca8418_keypad_platform_data *pdata =
+ dev_get_platdata(dev);
+ struct tca8418_keypad *keypad_data;
+ struct input_dev *input;
+ const struct matrix_keymap_data *keymap_data = NULL;
+ u32 rows = 0, cols = 0;
+ bool rep = false;
+ bool irq_is_gpio = false;
+ int irq;
+ int error, row_shift, max_keys;
+
+ /* Copy the platform data */
+ if (pdata) {
+ if (!pdata->keymap_data) {
+ dev_err(dev, "no keymap data defined\n");
+ return -EINVAL;
+ }
+ keymap_data = pdata->keymap_data;
+ rows = pdata->rows;
+ cols = pdata->cols;
+ rep = pdata->rep;
+ irq_is_gpio = pdata->irq_is_gpio;
+ } else {
+ struct device_node *np = dev->of_node;
+ int err;
+
+ err = matrix_keypad_parse_of_params(dev, &rows, &cols);
+ if (err)
+ return err;
+ rep = of_property_read_bool(np, "keypad,autorepeat");
+ }
+
+ if (!rows || rows > TCA8418_MAX_ROWS) {
+ dev_err(dev, "invalid rows\n");
+ return -EINVAL;
+ }
+
+ if (!cols || cols > TCA8418_MAX_COLS) {
+ dev_err(dev, "invalid columns\n");
+ return -EINVAL;
+ }
+
+ /* Check i2c driver capabilities */
+ if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE)) {
+ dev_err(dev, "%s adapter not supported\n",
+ dev_driver_string(&client->adapter->dev));
+ return -ENODEV;
+ }
+
+ row_shift = get_count_order(cols);
+ max_keys = rows << row_shift;
+
+ /* Allocate memory for keypad_data and input device */
+ keypad_data = devm_kzalloc(dev, sizeof(*keypad_data), GFP_KERNEL);
+ if (!keypad_data)
+ return -ENOMEM;
+
+ keypad_data->client = client;
+ keypad_data->row_shift = row_shift;
+
+ /* Initialize the chip or fail if chip isn't present */
+ error = tca8418_configure(keypad_data, rows, cols);
+ if (error < 0)
+ return error;
+
+ /* Configure input device */
+ input = devm_input_allocate_device(dev);
+ if (!input)
+ return -ENOMEM;
+
+ keypad_data->input = input;
+
+ input->name = client->name;
+ input->id.bustype = BUS_I2C;
+ input->id.vendor = 0x0001;
+ input->id.product = 0x001;
+ input->id.version = 0x0001;
+
+ error = matrix_keypad_build_keymap(keymap_data, NULL, rows, cols,
+ NULL, input);
+ if (error) {
+ dev_err(dev, "Failed to build keymap\n");
+ return error;
+ }
+
+ if (rep)
+ __set_bit(EV_REP, input->evbit);
+ input_set_capability(input, EV_MSC, MSC_SCAN);
+
+ input_set_drvdata(input, keypad_data);
+
+ irq = client->irq;
+ if (irq_is_gpio)
+ irq = gpio_to_irq(irq);
+
+ error = devm_request_threaded_irq(dev, irq, NULL, tca8418_irq_handler,
+ IRQF_TRIGGER_FALLING |
+ IRQF_SHARED |
+ IRQF_ONESHOT,
+ client->name, keypad_data);
+ if (error) {
+ dev_err(dev, "Unable to claim irq %d; error %d\n",
+ client->irq, error);
+ return error;
+ }
+
+ error = input_register_device(input);
+ if (error) {
+ dev_err(dev, "Unable to register input device, error: %d\n",
+ error);
+ return error;
+ }
+
+ return 0;
+}
+
+static const struct i2c_device_id tca8418_id[] = {
+ { TCA8418_NAME, 8418, },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, tca8418_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id tca8418_dt_ids[] = {
+ { .compatible = "ti,tca8418", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, tca8418_dt_ids);
+
+/*
+ * The device tree based i2c loader looks for
+ * "i2c:" + second_component_of(property("compatible"))
+ * and therefore we need an alias to be found.
+ */
+MODULE_ALIAS("i2c:tca8418");
+#endif
+
+static struct i2c_driver tca8418_keypad_driver = {
+ .driver = {
+ .name = TCA8418_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = of_match_ptr(tca8418_dt_ids),
+ },
+ .probe = tca8418_keypad_probe,
+ .id_table = tca8418_id,
+};
+
+static int __init tca8418_keypad_init(void)
+{
+ return i2c_add_driver(&tca8418_keypad_driver);
+}
+subsys_initcall(tca8418_keypad_init);
+
+static void __exit tca8418_keypad_exit(void)
+{
+ i2c_del_driver(&tca8418_keypad_driver);
+}
+module_exit(tca8418_keypad_exit);
+
+MODULE_AUTHOR("Kyle Manna <kyle.manna@fuel7.com>");
+MODULE_DESCRIPTION("Keypad driver for TCA8418");
+MODULE_LICENSE("GPL");
Code Review / kvmfornfv.git / blobdiff