/* * Driver for TCA8418 I2C keyboard * * Copyright (C) 2011 Fuel7, Inc. All rights reserved. * * Author: Kyle Manna * * 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 #include #include #include #include #include #include #include #include #include #include #include /* 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 { unsigned int irq; unsigned int row_shift; struct i2c_client *client; struct input_dev *input; /* Flexible array member, must be at end of struct */ unsigned short keymap[]; }; /* * 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) { 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(keypad_data->input, EV_MSC, MSC_SCAN, code); input_report_key(keypad_data->input, keypad_data->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(keypad_data->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 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; of_property_read_u32(np, "keypad,num-rows", &rows); of_property_read_u32(np, "keypad,num-columns", &cols); 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, keymap and input device */ keypad_data = kzalloc(sizeof(*keypad_data) + max_keys * sizeof(keypad_data->keymap[0]), 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) goto fail1; /* Configure input device */ input = input_allocate_device(); if (!input) { error = -ENOMEM; goto fail1; } keypad_data->input = input; input->name = client->name; input->dev.parent = &client->dev; 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, keypad_data->keymap, input); if (error) { dev_err(dev, "Failed to build keymap\n"); goto fail2; } if (rep) __set_bit(EV_REP, input->evbit); input_set_capability(input, EV_MSC, MSC_SCAN); input_set_drvdata(input, keypad_data); if (irq_is_gpio) client->irq = gpio_to_irq(client->irq); error = request_threaded_irq(client->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); goto fail2; } error = input_register_device(input); if (error) { dev_err(dev, "Unable to register input device, error: %d\n", error); goto fail3; } i2c_set_clientdata(client, keypad_data); return 0; fail3: free_irq(client->irq, keypad_data); fail2: input_free_device(input); fail1: kfree(keypad_data); return error; } static int tca8418_keypad_remove(struct i2c_client *client) { struct tca8418_keypad *keypad_data = i2c_get_clientdata(client); free_irq(keypad_data->client->irq, keypad_data); input_unregister_device(keypad_data->input); kfree(keypad_data); 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[] __devinitconst = { { .compatible = "ti,tca8418", }, { } }; MODULE_DEVICE_TABLE(of, tca8418_dt_ids); #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, .remove = tca8418_keypad_remove, .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 "); MODULE_DESCRIPTION("Keypad driver for TCA8418"); MODULE_LICENSE("GPL");