diff options
Diffstat (limited to 'drivers/input/keyboard/pinephone-keyboard.c')
| -rw-r--r-- | drivers/input/keyboard/pinephone-keyboard.c | 450 |
1 files changed, 450 insertions, 0 deletions
diff --git a/drivers/input/keyboard/pinephone-keyboard.c b/drivers/input/keyboard/pinephone-keyboard.c new file mode 100644 index 0000000000..147b1f288a --- /dev/null +++ b/drivers/input/keyboard/pinephone-keyboard.c @@ -0,0 +1,450 @@ +// SPDX-License-Identifier: GPL-2.0-only +// +// Copyright (C) 2021-2022 Samuel Holland <samuel@sholland.org> + +#include <linux/crc8.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/input/matrix_keypad.h> +#include <linux/interrupt.h> +#include <linux/module.h> +#include <linux/mod_devicetable.h> +#include <linux/of.h> +#include <linux/regulator/consumer.h> +#include <linux/types.h> + +#define DRV_NAME "pinephone-keyboard" + +#define PPKB_CRC8_POLYNOMIAL 0x07 + +#define PPKB_DEVICE_ID_HI 0x00 +#define PPKB_DEVICE_ID_HI_VALUE 'K' +#define PPKB_DEVICE_ID_LO 0x01 +#define PPKB_DEVICE_ID_LO_VALUE 'B' +#define PPKB_FW_REVISION 0x02 +#define PPKB_FW_FEATURES 0x03 +#define PPKB_MATRIX_SIZE 0x06 +#define PPKB_SCAN_CRC 0x07 +#define PPKB_SCAN_DATA 0x08 +#define PPKB_SYS_CONFIG 0x20 +#define PPKB_SYS_CONFIG_DISABLE_SCAN BIT(0) +#define PPKB_SYS_SMBUS_COMMAND 0x21 +#define PPKB_SYS_SMBUS_DATA 0x22 +#define PPKB_SYS_COMMAND 0x23 +#define PPKB_SYS_COMMAND_SMBUS_READ 0x91 +#define PPKB_SYS_COMMAND_SMBUS_WRITE 0xa1 + +#define PPKB_ROWS 6 +#define PPKB_COLS 12 + +/* Size of the scan buffer, including the CRC byte at the beginning. */ +#define PPKB_BUF_LEN (1 + PPKB_COLS) + +static const uint32_t ppkb_keymap[] = { + KEY(0, 0, KEY_ESC), + KEY(0, 1, KEY_1), + KEY(0, 2, KEY_2), + KEY(0, 3, KEY_3), + KEY(0, 4, KEY_4), + KEY(0, 5, KEY_5), + KEY(0, 6, KEY_6), + KEY(0, 7, KEY_7), + KEY(0, 8, KEY_8), + KEY(0, 9, KEY_9), + KEY(0, 10, KEY_0), + KEY(0, 11, KEY_BACKSPACE), + + KEY(1, 0, KEY_TAB), + KEY(1, 1, KEY_Q), + KEY(1, 2, KEY_W), + KEY(1, 3, KEY_E), + KEY(1, 4, KEY_R), + KEY(1, 5, KEY_T), + KEY(1, 6, KEY_Y), + KEY(1, 7, KEY_U), + KEY(1, 8, KEY_I), + KEY(1, 9, KEY_O), + KEY(1, 10, KEY_P), + KEY(1, 11, KEY_ENTER), + + KEY(2, 0, KEY_LEFTMETA), + KEY(2, 1, KEY_A), + KEY(2, 2, KEY_S), + KEY(2, 3, KEY_D), + KEY(2, 4, KEY_F), + KEY(2, 5, KEY_G), + KEY(2, 6, KEY_H), + KEY(2, 7, KEY_J), + KEY(2, 8, KEY_K), + KEY(2, 9, KEY_L), + KEY(2, 10, KEY_SEMICOLON), + + KEY(3, 0, KEY_LEFTSHIFT), + KEY(3, 1, KEY_Z), + KEY(3, 2, KEY_X), + KEY(3, 3, KEY_C), + KEY(3, 4, KEY_V), + KEY(3, 5, KEY_B), + KEY(3, 6, KEY_N), + KEY(3, 7, KEY_M), + KEY(3, 8, KEY_COMMA), + KEY(3, 9, KEY_DOT), + KEY(3, 10, KEY_SLASH), + + KEY(4, 1, KEY_LEFTCTRL), + KEY(4, 4, KEY_SPACE), + KEY(4, 6, KEY_APOSTROPHE), + KEY(4, 8, KEY_RIGHTBRACE), + KEY(4, 9, KEY_LEFTBRACE), + + KEY(5, 2, KEY_FN), + KEY(5, 3, KEY_LEFTALT), + KEY(5, 5, KEY_RIGHTALT), + + /* FN layer */ + KEY(PPKB_ROWS + 0, 0, KEY_FN_ESC), + KEY(PPKB_ROWS + 0, 1, KEY_F1), + KEY(PPKB_ROWS + 0, 2, KEY_F2), + KEY(PPKB_ROWS + 0, 3, KEY_F3), + KEY(PPKB_ROWS + 0, 4, KEY_F4), + KEY(PPKB_ROWS + 0, 5, KEY_F5), + KEY(PPKB_ROWS + 0, 6, KEY_F6), + KEY(PPKB_ROWS + 0, 7, KEY_F7), + KEY(PPKB_ROWS + 0, 8, KEY_F8), + KEY(PPKB_ROWS + 0, 9, KEY_F9), + KEY(PPKB_ROWS + 0, 10, KEY_F10), + KEY(PPKB_ROWS + 0, 11, KEY_DELETE), + + KEY(PPKB_ROWS + 1, 10, KEY_PAGEUP), + + KEY(PPKB_ROWS + 2, 0, KEY_SYSRQ), + KEY(PPKB_ROWS + 2, 9, KEY_PAGEDOWN), + KEY(PPKB_ROWS + 2, 10, KEY_INSERT), + + KEY(PPKB_ROWS + 3, 0, KEY_LEFTSHIFT), + KEY(PPKB_ROWS + 3, 8, KEY_HOME), + KEY(PPKB_ROWS + 3, 9, KEY_UP), + KEY(PPKB_ROWS + 3, 10, KEY_END), + + KEY(PPKB_ROWS + 4, 1, KEY_LEFTCTRL), + KEY(PPKB_ROWS + 4, 6, KEY_LEFT), + KEY(PPKB_ROWS + 4, 8, KEY_RIGHT), + KEY(PPKB_ROWS + 4, 9, KEY_DOWN), + + KEY(PPKB_ROWS + 5, 3, KEY_LEFTALT), + KEY(PPKB_ROWS + 5, 5, KEY_RIGHTALT), +}; + +static const struct matrix_keymap_data ppkb_keymap_data = { + .keymap = ppkb_keymap, + .keymap_size = ARRAY_SIZE(ppkb_keymap), +}; + +struct pinephone_keyboard { + struct i2c_adapter adapter; + struct input_dev *input; + u8 buf[2][PPKB_BUF_LEN]; + u8 crc_table[CRC8_TABLE_SIZE]; + u8 fn_state[PPKB_COLS]; + bool buf_swap; + bool fn_pressed; +}; + +static int ppkb_adap_smbus_xfer(struct i2c_adapter *adap, u16 addr, + unsigned short flags, char read_write, + u8 command, int size, + union i2c_smbus_data *data) +{ + struct i2c_client *client = adap->algo_data; + u8 buf[3]; + int ret; + + buf[0] = command; + buf[1] = data->byte; + buf[2] = read_write == I2C_SMBUS_READ ? PPKB_SYS_COMMAND_SMBUS_READ + : PPKB_SYS_COMMAND_SMBUS_WRITE; + + ret = i2c_smbus_write_i2c_block_data(client, PPKB_SYS_SMBUS_COMMAND, + sizeof(buf), buf); + if (ret) + return ret; + + /* Read back the command status until it passes or fails. */ + do { + usleep_range(300, 500); + ret = i2c_smbus_read_byte_data(client, PPKB_SYS_COMMAND); + } while (ret == buf[2]); + if (ret < 0) + return ret; + /* Commands return 0x00 on success and 0xff on failure. */ + if (ret) + return -EIO; + + if (read_write == I2C_SMBUS_READ) { + ret = i2c_smbus_read_byte_data(client, PPKB_SYS_SMBUS_DATA); + if (ret < 0) + return ret; + + data->byte = ret; + } + + return 0; +} + +static u32 ppkg_adap_functionality(struct i2c_adapter *adap) +{ + return I2C_FUNC_SMBUS_BYTE_DATA; +} + +static const struct i2c_algorithm ppkb_adap_algo = { + .smbus_xfer = ppkb_adap_smbus_xfer, + .functionality = ppkg_adap_functionality, +}; + +static void ppkb_update(struct i2c_client *client) +{ + struct pinephone_keyboard *ppkb = i2c_get_clientdata(client); + unsigned short *keymap = ppkb->input->keycode; + int row_shift = get_count_order(PPKB_COLS); + u8 *old_buf = ppkb->buf[!ppkb->buf_swap]; + u8 *new_buf = ppkb->buf[ppkb->buf_swap]; + int col, crc, ret, row; + struct device *dev = &client->dev; + + ret = i2c_smbus_read_i2c_block_data(client, PPKB_SCAN_CRC, + PPKB_BUF_LEN, new_buf); + if (ret != PPKB_BUF_LEN) { + dev_err(dev, "Failed to read scan data: %d\n", ret); + return; + } + + crc = crc8(ppkb->crc_table, &new_buf[1], PPKB_COLS, CRC8_INIT_VALUE); + if (crc != new_buf[0]) { + dev_err(dev, "Bad scan data (%02x != %02x)\n", crc, new_buf[0]); + return; + } + + ppkb->buf_swap = !ppkb->buf_swap; + + for (col = 0; col < PPKB_COLS; ++col) { + u8 old = old_buf[1 + col]; + u8 new = new_buf[1 + col]; + u8 changed = old ^ new; + + if (!changed) + continue; + + for (row = 0; row < PPKB_ROWS; ++row) { + u8 mask = BIT(row); + u8 value = new & mask; + unsigned short code; + bool fn_state; + + if (!(changed & mask)) + continue; + + /* + * Save off the FN key state when the key was pressed, + * and use that to determine the code during a release. + */ + fn_state = value ? ppkb->fn_pressed : ppkb->fn_state[col] & mask; + if (fn_state) + ppkb->fn_state[col] ^= mask; + + /* The FN layer is a second set of rows. */ + code = MATRIX_SCAN_CODE(fn_state ? PPKB_ROWS + row : row, + col, row_shift); + input_event(ppkb->input, EV_MSC, MSC_SCAN, code); + input_report_key(ppkb->input, keymap[code], value); + if (keymap[code] == KEY_FN) + ppkb->fn_pressed = value; + } + } + input_sync(ppkb->input); +} + +static irqreturn_t ppkb_irq_thread(int irq, void *data) +{ + struct i2c_client *client = data; + + ppkb_update(client); + + return IRQ_HANDLED; +} + +static int ppkb_set_scan(struct i2c_client *client, bool enable) +{ + struct device *dev = &client->dev; + int ret, val; + + ret = i2c_smbus_read_byte_data(client, PPKB_SYS_CONFIG); + if (ret < 0) { + dev_err(dev, "Failed to read config: %d\n", ret); + return ret; + } + + if (enable) + val = ret & ~PPKB_SYS_CONFIG_DISABLE_SCAN; + else + val = ret | PPKB_SYS_CONFIG_DISABLE_SCAN; + + ret = i2c_smbus_write_byte_data(client, PPKB_SYS_CONFIG, val); + if (ret) { + dev_err(dev, "Failed to write config: %d\n", ret); + return ret; + } + + return 0; +} + +static int ppkb_open(struct input_dev *input) +{ + struct i2c_client *client = input_get_drvdata(input); + int error; + + error = ppkb_set_scan(client, true); + if (error) + return error; + + return 0; +} + +static void ppkb_close(struct input_dev *input) +{ + struct i2c_client *client = input_get_drvdata(input); + + ppkb_set_scan(client, false); +} + +static int ppkb_probe(struct i2c_client *client) +{ + struct device *dev = &client->dev; + unsigned int phys_rows, phys_cols; + struct pinephone_keyboard *ppkb; + u8 info[PPKB_MATRIX_SIZE + 1]; + struct device_node *i2c_bus; + int ret; + int error; + + error = devm_regulator_get_enable(dev, "vbat"); + if (error) { + dev_err(dev, "Failed to get VBAT supply: %d\n", error); + return error; + } + + ret = i2c_smbus_read_i2c_block_data(client, 0, sizeof(info), info); + if (ret != sizeof(info)) { + error = ret < 0 ? ret : -EIO; + dev_err(dev, "Failed to read device ID: %d\n", error); + return error; + } + + if (info[PPKB_DEVICE_ID_HI] != PPKB_DEVICE_ID_HI_VALUE || + info[PPKB_DEVICE_ID_LO] != PPKB_DEVICE_ID_LO_VALUE) { + dev_warn(dev, "Unexpected device ID: %#02x %#02x\n", + info[PPKB_DEVICE_ID_HI], info[PPKB_DEVICE_ID_LO]); + return -ENODEV; + } + + dev_info(dev, "Found firmware version %d.%d features %#x\n", + info[PPKB_FW_REVISION] >> 4, + info[PPKB_FW_REVISION] & 0xf, + info[PPKB_FW_FEATURES]); + + phys_rows = info[PPKB_MATRIX_SIZE] & 0xf; + phys_cols = info[PPKB_MATRIX_SIZE] >> 4; + if (phys_rows != PPKB_ROWS || phys_cols != PPKB_COLS) { + dev_err(dev, "Unexpected keyboard size %ux%u\n", + phys_rows, phys_cols); + return -EINVAL; + } + + /* Disable scan by default to save power. */ + error = ppkb_set_scan(client, false); + if (error) + return error; + + ppkb = devm_kzalloc(dev, sizeof(*ppkb), GFP_KERNEL); + if (!ppkb) + return -ENOMEM; + + i2c_set_clientdata(client, ppkb); + + i2c_bus = of_get_child_by_name(dev->of_node, "i2c"); + if (i2c_bus) { + ppkb->adapter.owner = THIS_MODULE; + ppkb->adapter.algo = &ppkb_adap_algo; + ppkb->adapter.algo_data = client; + ppkb->adapter.dev.parent = dev; + ppkb->adapter.dev.of_node = i2c_bus; + strscpy(ppkb->adapter.name, DRV_NAME, sizeof(ppkb->adapter.name)); + + error = devm_i2c_add_adapter(dev, &ppkb->adapter); + if (error) { + dev_err(dev, "Failed to add I2C adapter: %d\n", error); + return error; + } + } + + crc8_populate_msb(ppkb->crc_table, PPKB_CRC8_POLYNOMIAL); + + ppkb->input = devm_input_allocate_device(dev); + if (!ppkb->input) + return -ENOMEM; + + input_set_drvdata(ppkb->input, client); + + ppkb->input->name = "PinePhone Keyboard"; + ppkb->input->phys = DRV_NAME "/input0"; + ppkb->input->id.bustype = BUS_I2C; + ppkb->input->open = ppkb_open; + ppkb->input->close = ppkb_close; + + input_set_capability(ppkb->input, EV_MSC, MSC_SCAN); + __set_bit(EV_REP, ppkb->input->evbit); + + error = matrix_keypad_build_keymap(&ppkb_keymap_data, NULL, + 2 * PPKB_ROWS, PPKB_COLS, NULL, + ppkb->input); + if (error) { + dev_err(dev, "Failed to build keymap: %d\n", error); + return error; + } + + error = input_register_device(ppkb->input); + if (error) { + dev_err(dev, "Failed to register input: %d\n", error); + return error; + } + + error = devm_request_threaded_irq(dev, client->irq, + NULL, ppkb_irq_thread, + IRQF_ONESHOT, client->name, client); + if (error) { + dev_err(dev, "Failed to request IRQ: %d\n", error); + return error; + } + + return 0; +} + +static const struct of_device_id ppkb_of_match[] = { + { .compatible = "pine64,pinephone-keyboard" }, + { } +}; +MODULE_DEVICE_TABLE(of, ppkb_of_match); + +static struct i2c_driver ppkb_driver = { + .probe = ppkb_probe, + .driver = { + .name = DRV_NAME, + .of_match_table = ppkb_of_match, + }, +}; +module_i2c_driver(ppkb_driver); + +MODULE_AUTHOR("Samuel Holland <samuel@sholland.org>"); +MODULE_DESCRIPTION("Pine64 PinePhone keyboard driver"); +MODULE_LICENSE("GPL"); |