diff options
Diffstat (limited to 'drivers/input/keyboard/qt1050.c')
-rw-r--r-- | drivers/input/keyboard/qt1050.c | 598 |
1 files changed, 598 insertions, 0 deletions
diff --git a/drivers/input/keyboard/qt1050.c b/drivers/input/keyboard/qt1050.c new file mode 100644 index 000000000000..403060d05c3b --- /dev/null +++ b/drivers/input/keyboard/qt1050.c @@ -0,0 +1,598 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Microchip AT42QT1050 QTouch Sensor Controller + * + * Copyright (C) 2019 Pengutronix, Marco Felsch <kernel@pengutronix.de> + * + * Base on AT42QT1070 driver by: + * Bo Shen <voice.shen@atmel.com> + * Copyright (C) 2011 Atmel + */ + +#include <linux/delay.h> +#include <linux/i2c.h> +#include <linux/input.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/log2.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/regmap.h> + +/* Chip ID */ +#define QT1050_CHIP_ID 0x00 +#define QT1050_CHIP_ID_VER 0x46 + +/* Firmware version */ +#define QT1050_FW_VERSION 0x01 + +/* Detection status */ +#define QT1050_DET_STATUS 0x02 + +/* Key status */ +#define QT1050_KEY_STATUS 0x03 + +/* Key Signals */ +#define QT1050_KEY_SIGNAL_0_MSB 0x06 +#define QT1050_KEY_SIGNAL_0_LSB 0x07 +#define QT1050_KEY_SIGNAL_1_MSB 0x08 +#define QT1050_KEY_SIGNAL_1_LSB 0x09 +#define QT1050_KEY_SIGNAL_2_MSB 0x0c +#define QT1050_KEY_SIGNAL_2_LSB 0x0d +#define QT1050_KEY_SIGNAL_3_MSB 0x0e +#define QT1050_KEY_SIGNAL_3_LSB 0x0f +#define QT1050_KEY_SIGNAL_4_MSB 0x10 +#define QT1050_KEY_SIGNAL_4_LSB 0x11 + +/* Reference data */ +#define QT1050_REF_DATA_0_MSB 0x14 +#define QT1050_REF_DATA_0_LSB 0x15 +#define QT1050_REF_DATA_1_MSB 0x16 +#define QT1050_REF_DATA_1_LSB 0x17 +#define QT1050_REF_DATA_2_MSB 0x1a +#define QT1050_REF_DATA_2_LSB 0x1b +#define QT1050_REF_DATA_3_MSB 0x1c +#define QT1050_REF_DATA_3_LSB 0x1d +#define QT1050_REF_DATA_4_MSB 0x1e +#define QT1050_REF_DATA_4_LSB 0x1f + +/* Negative threshold level */ +#define QT1050_NTHR_0 0x21 +#define QT1050_NTHR_1 0x22 +#define QT1050_NTHR_2 0x24 +#define QT1050_NTHR_3 0x25 +#define QT1050_NTHR_4 0x26 + +/* Pulse / Scale */ +#define QT1050_PULSE_SCALE_0 0x28 +#define QT1050_PULSE_SCALE_1 0x29 +#define QT1050_PULSE_SCALE_2 0x2b +#define QT1050_PULSE_SCALE_3 0x2c +#define QT1050_PULSE_SCALE_4 0x2d + +/* Detection integrator counter / AKS */ +#define QT1050_DI_AKS_0 0x2f +#define QT1050_DI_AKS_1 0x30 +#define QT1050_DI_AKS_2 0x32 +#define QT1050_DI_AKS_3 0x33 +#define QT1050_DI_AKS_4 0x34 + +/* Charge Share Delay */ +#define QT1050_CSD_0 0x36 +#define QT1050_CSD_1 0x37 +#define QT1050_CSD_2 0x39 +#define QT1050_CSD_3 0x3a +#define QT1050_CSD_4 0x3b + +/* Low Power Mode */ +#define QT1050_LPMODE 0x3d + +/* Calibration and Reset */ +#define QT1050_RES_CAL 0x3f +#define QT1050_RES_CAL_RESET BIT(7) +#define QT1050_RES_CAL_CALIBRATE BIT(1) + +#define QT1050_MAX_KEYS 5 +#define QT1050_RESET_TIME 255 + +struct qt1050_key_regs { + unsigned int nthr; + unsigned int pulse_scale; + unsigned int di_aks; + unsigned int csd; +}; + +struct qt1050_key { + u32 num; + u32 charge_delay; + u32 thr_cnt; + u32 samples; + u32 scale; + u32 keycode; +}; + +struct qt1050_priv { + struct i2c_client *client; + struct input_dev *input; + struct regmap *regmap; + struct qt1050_key keys[QT1050_MAX_KEYS]; + unsigned short keycodes[QT1050_MAX_KEYS]; + u8 reg_keys; + u8 last_keys; +}; + +static const struct qt1050_key_regs qt1050_key_regs_data[] = { + { + .nthr = QT1050_NTHR_0, + .pulse_scale = QT1050_PULSE_SCALE_0, + .di_aks = QT1050_DI_AKS_0, + .csd = QT1050_CSD_0, + }, { + .nthr = QT1050_NTHR_1, + .pulse_scale = QT1050_PULSE_SCALE_1, + .di_aks = QT1050_DI_AKS_1, + .csd = QT1050_CSD_1, + }, { + .nthr = QT1050_NTHR_2, + .pulse_scale = QT1050_PULSE_SCALE_2, + .di_aks = QT1050_DI_AKS_2, + .csd = QT1050_CSD_2, + }, { + .nthr = QT1050_NTHR_3, + .pulse_scale = QT1050_PULSE_SCALE_3, + .di_aks = QT1050_DI_AKS_3, + .csd = QT1050_CSD_3, + }, { + .nthr = QT1050_NTHR_4, + .pulse_scale = QT1050_PULSE_SCALE_4, + .di_aks = QT1050_DI_AKS_4, + .csd = QT1050_CSD_4, + } +}; + +static bool qt1050_volatile_reg(struct device *dev, unsigned int reg) +{ + switch (reg) { + case QT1050_DET_STATUS: + case QT1050_KEY_STATUS: + case QT1050_KEY_SIGNAL_0_MSB: + case QT1050_KEY_SIGNAL_0_LSB: + case QT1050_KEY_SIGNAL_1_MSB: + case QT1050_KEY_SIGNAL_1_LSB: + case QT1050_KEY_SIGNAL_2_MSB: + case QT1050_KEY_SIGNAL_2_LSB: + case QT1050_KEY_SIGNAL_3_MSB: + case QT1050_KEY_SIGNAL_3_LSB: + case QT1050_KEY_SIGNAL_4_MSB: + case QT1050_KEY_SIGNAL_4_LSB: + return true; + default: + return false; + } +} + +static const struct regmap_range qt1050_readable_ranges[] = { + regmap_reg_range(QT1050_CHIP_ID, QT1050_KEY_STATUS), + regmap_reg_range(QT1050_KEY_SIGNAL_0_MSB, QT1050_KEY_SIGNAL_1_LSB), + regmap_reg_range(QT1050_KEY_SIGNAL_2_MSB, QT1050_KEY_SIGNAL_4_LSB), + regmap_reg_range(QT1050_REF_DATA_0_MSB, QT1050_REF_DATA_1_LSB), + regmap_reg_range(QT1050_REF_DATA_2_MSB, QT1050_REF_DATA_4_LSB), + regmap_reg_range(QT1050_NTHR_0, QT1050_NTHR_1), + regmap_reg_range(QT1050_NTHR_2, QT1050_NTHR_4), + regmap_reg_range(QT1050_PULSE_SCALE_0, QT1050_PULSE_SCALE_1), + regmap_reg_range(QT1050_PULSE_SCALE_2, QT1050_PULSE_SCALE_4), + regmap_reg_range(QT1050_DI_AKS_0, QT1050_DI_AKS_1), + regmap_reg_range(QT1050_DI_AKS_2, QT1050_DI_AKS_4), + regmap_reg_range(QT1050_CSD_0, QT1050_CSD_1), + regmap_reg_range(QT1050_CSD_2, QT1050_RES_CAL), +}; + +static const struct regmap_access_table qt1050_readable_table = { + .yes_ranges = qt1050_readable_ranges, + .n_yes_ranges = ARRAY_SIZE(qt1050_readable_ranges), +}; + +static const struct regmap_range qt1050_writeable_ranges[] = { + regmap_reg_range(QT1050_NTHR_0, QT1050_NTHR_1), + regmap_reg_range(QT1050_NTHR_2, QT1050_NTHR_4), + regmap_reg_range(QT1050_PULSE_SCALE_0, QT1050_PULSE_SCALE_1), + regmap_reg_range(QT1050_PULSE_SCALE_2, QT1050_PULSE_SCALE_4), + regmap_reg_range(QT1050_DI_AKS_0, QT1050_DI_AKS_1), + regmap_reg_range(QT1050_DI_AKS_2, QT1050_DI_AKS_4), + regmap_reg_range(QT1050_CSD_0, QT1050_CSD_1), + regmap_reg_range(QT1050_CSD_2, QT1050_RES_CAL), +}; + +static const struct regmap_access_table qt1050_writeable_table = { + .yes_ranges = qt1050_writeable_ranges, + .n_yes_ranges = ARRAY_SIZE(qt1050_writeable_ranges), +}; + +static struct regmap_config qt1050_regmap_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = QT1050_RES_CAL, + + .cache_type = REGCACHE_RBTREE, + + .wr_table = &qt1050_writeable_table, + .rd_table = &qt1050_readable_table, + .volatile_reg = qt1050_volatile_reg, +}; + +static bool qt1050_identify(struct qt1050_priv *ts) +{ + unsigned int val; + int err; + + /* Read Chip ID */ + regmap_read(ts->regmap, QT1050_CHIP_ID, &val); + if (val != QT1050_CHIP_ID_VER) { + dev_err(&ts->client->dev, "ID %d not supported\n", val); + return false; + } + + /* Read firmware version */ + err = regmap_read(ts->regmap, QT1050_FW_VERSION, &val); + if (err) { + dev_err(&ts->client->dev, "could not read the firmware version\n"); + return false; + } + + dev_info(&ts->client->dev, "AT42QT1050 firmware version %1d.%1d\n", + val >> 4, val & 0xf); + + return true; +} + +static irqreturn_t qt1050_irq_threaded(int irq, void *dev_id) +{ + struct qt1050_priv *ts = dev_id; + struct input_dev *input = ts->input; + unsigned long new_keys, changed; + unsigned int val; + int i, err; + + /* Read the detected status register, thus clearing interrupt */ + err = regmap_read(ts->regmap, QT1050_DET_STATUS, &val); + if (err) { + dev_err(&ts->client->dev, "Fail to read detection status: %d\n", + err); + return IRQ_NONE; + } + + /* Read which key changed, keys are not continuous */ + err = regmap_read(ts->regmap, QT1050_KEY_STATUS, &val); + if (err) { + dev_err(&ts->client->dev, + "Fail to determine the key status: %d\n", err); + return IRQ_NONE; + } + new_keys = (val & 0x70) >> 2 | (val & 0x6) >> 1; + changed = ts->last_keys ^ new_keys; + /* Report registered keys only */ + changed &= ts->reg_keys; + + for_each_set_bit(i, &changed, QT1050_MAX_KEYS) + input_report_key(input, ts->keys[i].keycode, + test_bit(i, &new_keys)); + + ts->last_keys = new_keys; + input_sync(input); + + return IRQ_HANDLED; +} + +static const struct qt1050_key_regs *qt1050_get_key_regs(int key_num) +{ + return &qt1050_key_regs_data[key_num]; +} + +static int qt1050_set_key(struct regmap *map, int number, int on) +{ + const struct qt1050_key_regs *key_regs; + + key_regs = qt1050_get_key_regs(number); + + return regmap_update_bits(map, key_regs->di_aks, 0xfc, + on ? BIT(4) : 0x00); +} + +static int qt1050_apply_fw_data(struct qt1050_priv *ts) +{ + struct regmap *map = ts->regmap; + struct qt1050_key *button = &ts->keys[0]; + const struct qt1050_key_regs *key_regs; + int i, err; + + /* Disable all keys and enable only the specified ones */ + for (i = 0; i < QT1050_MAX_KEYS; i++) { + err = qt1050_set_key(map, i, 0); + if (err) + return err; + } + + for (i = 0; i < QT1050_MAX_KEYS; i++, button++) { + /* Keep KEY_RESERVED keys off */ + if (button->keycode == KEY_RESERVED) + continue; + + err = qt1050_set_key(map, button->num, 1); + if (err) + return err; + + key_regs = qt1050_get_key_regs(button->num); + + err = regmap_write(map, key_regs->pulse_scale, + (button->samples << 4) | (button->scale)); + if (err) + return err; + err = regmap_write(map, key_regs->csd, button->charge_delay); + if (err) + return err; + err = regmap_write(map, key_regs->nthr, button->thr_cnt); + if (err) + return err; + } + + return 0; +} + +static int qt1050_parse_fw(struct qt1050_priv *ts) +{ + struct device *dev = &ts->client->dev; + struct fwnode_handle *child; + int nbuttons; + + nbuttons = device_get_child_node_count(dev); + if (nbuttons == 0 || nbuttons > QT1050_MAX_KEYS) + return -ENODEV; + + device_for_each_child_node(dev, child) { + struct qt1050_key button; + + /* Required properties */ + if (fwnode_property_read_u32(child, "linux,code", + &button.keycode)) { + dev_err(dev, "Button without keycode\n"); + goto err; + } + if (button.keycode >= KEY_MAX) { + dev_err(dev, "Invalid keycode 0x%x\n", + button.keycode); + goto err; + } + + if (fwnode_property_read_u32(child, "reg", + &button.num)) { + dev_err(dev, "Button without pad number\n"); + goto err; + } + if (button.num < 0 || button.num > QT1050_MAX_KEYS - 1) + goto err; + + ts->reg_keys |= BIT(button.num); + + /* Optional properties */ + if (fwnode_property_read_u32(child, + "microchip,pre-charge-time-ns", + &button.charge_delay)) { + button.charge_delay = 0; + } else { + if (button.charge_delay % 2500 == 0) + button.charge_delay = + button.charge_delay / 2500; + else + button.charge_delay = 0; + } + + if (fwnode_property_read_u32(child, "microchip,average-samples", + &button.samples)) { + button.samples = 0; + } else { + if (is_power_of_2(button.samples)) + button.samples = ilog2(button.samples); + else + button.samples = 0; + } + + if (fwnode_property_read_u32(child, "microchip,average-scaling", + &button.scale)) { + button.scale = 0; + } else { + if (is_power_of_2(button.scale)) + button.scale = ilog2(button.scale); + else + button.scale = 0; + + } + + if (fwnode_property_read_u32(child, "microchip,threshold", + &button.thr_cnt)) { + button.thr_cnt = 20; + } else { + if (button.thr_cnt > 255) + button.thr_cnt = 20; + } + + ts->keys[button.num] = button; + } + + return 0; + +err: + fwnode_handle_put(child); + return -EINVAL; +} + +static int qt1050_probe(struct i2c_client *client) +{ + struct qt1050_priv *ts; + struct input_dev *input; + struct device *dev = &client->dev; + struct regmap *map; + unsigned int status, i; + int err; + + /* Check basic functionality */ + err = i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_BYTE); + if (!err) { + dev_err(&client->dev, "%s adapter not supported\n", + dev_driver_string(&client->adapter->dev)); + return -ENODEV; + } + + if (!client->irq) { + dev_err(dev, "assign a irq line to this device\n"); + return -EINVAL; + } + + ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL); + if (!ts) + return -ENOMEM; + + input = devm_input_allocate_device(dev); + if (!input) + return -ENOMEM; + + map = devm_regmap_init_i2c(client, &qt1050_regmap_config); + if (IS_ERR(map)) + return PTR_ERR(map); + + ts->client = client; + ts->input = input; + ts->regmap = map; + + i2c_set_clientdata(client, ts); + + /* Identify the qt1050 chip */ + if (!qt1050_identify(ts)) + return -ENODEV; + + /* Get pdata */ + err = qt1050_parse_fw(ts); + if (err) { + dev_err(dev, "Failed to parse firmware: %d\n", err); + return err; + } + + input->name = "AT42QT1050 QTouch Sensor"; + input->dev.parent = &client->dev; + input->id.bustype = BUS_I2C; + + /* Add the keycode */ + input->keycode = ts->keycodes; + input->keycodesize = sizeof(ts->keycodes[0]); + input->keycodemax = QT1050_MAX_KEYS; + + __set_bit(EV_KEY, input->evbit); + for (i = 0; i < QT1050_MAX_KEYS; i++) { + ts->keycodes[i] = ts->keys[i].keycode; + __set_bit(ts->keycodes[i], input->keybit); + } + + /* Trigger re-calibration */ + err = regmap_update_bits(ts->regmap, QT1050_RES_CAL, 0x7f, + QT1050_RES_CAL_CALIBRATE); + if (err) { + dev_err(dev, "Trigger calibration failed: %d\n", err); + return err; + } + err = regmap_read_poll_timeout(ts->regmap, QT1050_DET_STATUS, status, + status >> 7 == 1, 10000, 200000); + if (err) { + dev_err(dev, "Calibration failed: %d\n", err); + return err; + } + + /* Soft reset to set defaults */ + err = regmap_update_bits(ts->regmap, QT1050_RES_CAL, + QT1050_RES_CAL_RESET, QT1050_RES_CAL_RESET); + if (err) { + dev_err(dev, "Trigger soft reset failed: %d\n", err); + return err; + } + msleep(QT1050_RESET_TIME); + + /* Set pdata */ + err = qt1050_apply_fw_data(ts); + if (err) { + dev_err(dev, "Failed to set firmware data: %d\n", err); + return err; + } + + err = devm_request_threaded_irq(dev, client->irq, NULL, + qt1050_irq_threaded, IRQF_ONESHOT, + "qt1050", ts); + if (err) { + dev_err(&client->dev, "Failed to request irq: %d\n", err); + return err; + } + + /* Clear #CHANGE line */ + err = regmap_read(ts->regmap, QT1050_DET_STATUS, &status); + if (err) { + dev_err(dev, "Failed to clear #CHANGE line level: %d\n", err); + return err; + } + + /* Register the input device */ + err = input_register_device(ts->input); + if (err) { + dev_err(&client->dev, "Failed to register input device: %d\n", + err); + return err; + } + + return 0; +} + +static int __maybe_unused qt1050_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct qt1050_priv *ts = i2c_get_clientdata(client); + + disable_irq(client->irq); + + /* + * Set measurement interval to 1s (125 x 8ms) if wakeup is allowed + * else turn off. The 1s interval seems to be a good compromise between + * low power and response time. + */ + return regmap_write(ts->regmap, QT1050_LPMODE, + device_may_wakeup(dev) ? 125 : 0); +} + +static int __maybe_unused qt1050_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct qt1050_priv *ts = i2c_get_clientdata(client); + + enable_irq(client->irq); + + /* Set measurement interval back to 16ms (2 x 8ms) */ + return regmap_write(ts->regmap, QT1050_LPMODE, 2); +} + +static SIMPLE_DEV_PM_OPS(qt1050_pm_ops, qt1050_suspend, qt1050_resume); + +static const struct of_device_id __maybe_unused qt1050_of_match[] = { + { .compatible = "microchip,qt1050", }, + { }, +}; +MODULE_DEVICE_TABLE(of, qt1050_of_match); + +static struct i2c_driver qt1050_driver = { + .driver = { + .name = "qt1050", + .of_match_table = of_match_ptr(qt1050_of_match), + .pm = &qt1050_pm_ops, + }, + .probe_new = qt1050_probe, +}; + +module_i2c_driver(qt1050_driver); + +MODULE_AUTHOR("Marco Felsch <kernel@pengutronix.de"); +MODULE_DESCRIPTION("Driver for AT42QT1050 QTouch sensor"); +MODULE_LICENSE("GPL v2"); |