// 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 */ err = regmap_read(ts->regmap, QT1050_CHIP_ID, &val); if (err) { dev_err(&ts->client->dev, "Failed to read chip ID: %d\n", err); return false; } 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 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 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 DEFINE_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 = pm_sleep_ptr(&qt1050_pm_ops), }, .probe = 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");