// SPDX-License-Identifier: GPL-2.0-only /* * Input driver for Microchip CAP11xx based capacitive touch sensors * * (c) 2014 Daniel Mack */ #include #include #include #include #include #include #include #include #include #include #define CAP11XX_REG_MAIN_CONTROL 0x00 #define CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT (6) #define CAP11XX_REG_MAIN_CONTROL_GAIN_MASK (0xc0) #define CAP11XX_REG_MAIN_CONTROL_DLSEEP BIT(4) #define CAP11XX_REG_GENERAL_STATUS 0x02 #define CAP11XX_REG_SENSOR_INPUT 0x03 #define CAP11XX_REG_NOISE_FLAG_STATUS 0x0a #define CAP11XX_REG_SENOR_DELTA(X) (0x10 + (X)) #define CAP11XX_REG_SENSITIVITY_CONTROL 0x1f #define CAP11XX_REG_SENSITIVITY_CONTROL_DELTA_SENSE_MASK 0x70 #define CAP11XX_REG_CONFIG 0x20 #define CAP11XX_REG_SENSOR_ENABLE 0x21 #define CAP11XX_REG_SENSOR_CONFIG 0x22 #define CAP11XX_REG_SENSOR_CONFIG2 0x23 #define CAP11XX_REG_SAMPLING_CONFIG 0x24 #define CAP11XX_REG_CALIBRATION 0x26 #define CAP11XX_REG_INT_ENABLE 0x27 #define CAP11XX_REG_REPEAT_RATE 0x28 #define CAP11XX_REG_SIGNAL_GUARD_ENABLE 0x29 #define CAP11XX_REG_MT_CONFIG 0x2a #define CAP11XX_REG_MT_PATTERN_CONFIG 0x2b #define CAP11XX_REG_MT_PATTERN 0x2d #define CAP11XX_REG_RECALIB_CONFIG 0x2f #define CAP11XX_REG_SENSOR_THRESH(X) (0x30 + (X)) #define CAP11XX_REG_SENSOR_NOISE_THRESH 0x38 #define CAP11XX_REG_STANDBY_CHANNEL 0x40 #define CAP11XX_REG_STANDBY_CONFIG 0x41 #define CAP11XX_REG_STANDBY_SENSITIVITY 0x42 #define CAP11XX_REG_STANDBY_THRESH 0x43 #define CAP11XX_REG_CONFIG2 0x44 #define CAP11XX_REG_CONFIG2_ALT_POL BIT(6) #define CAP11XX_REG_SENSOR_BASE_CNT(X) (0x50 + (X)) #define CAP11XX_REG_LED_POLARITY 0x73 #define CAP11XX_REG_LED_OUTPUT_CONTROL 0x74 #define CAP11XX_REG_CALIB_SENSITIVITY_CONFIG 0x80 #define CAP11XX_REG_CALIB_SENSITIVITY_CONFIG2 0x81 #define CAP11XX_REG_LED_DUTY_CYCLE_1 0x90 #define CAP11XX_REG_LED_DUTY_CYCLE_2 0x91 #define CAP11XX_REG_LED_DUTY_CYCLE_3 0x92 #define CAP11XX_REG_LED_DUTY_CYCLE_4 0x93 #define CAP11XX_REG_LED_DUTY_MIN_MASK (0x0f) #define CAP11XX_REG_LED_DUTY_MIN_MASK_SHIFT (0) #define CAP11XX_REG_LED_DUTY_MAX_MASK (0xf0) #define CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT (4) #define CAP11XX_REG_LED_DUTY_MAX_VALUE (15) #define CAP11XX_REG_SENSOR_CALIB (0xb1 + (X)) #define CAP11XX_REG_SENSOR_CALIB_LSB1 0xb9 #define CAP11XX_REG_SENSOR_CALIB_LSB2 0xba #define CAP11XX_REG_PRODUCT_ID 0xfd #define CAP11XX_REG_MANUFACTURER_ID 0xfe #define CAP11XX_REG_REVISION 0xff #define CAP11XX_MANUFACTURER_ID 0x5d #ifdef CONFIG_LEDS_CLASS struct cap11xx_led { struct cap11xx_priv *priv; struct led_classdev cdev; u32 reg; }; #endif struct cap11xx_priv { struct regmap *regmap; struct device *dev; struct input_dev *idev; const struct cap11xx_hw_model *model; u8 id; struct cap11xx_led *leds; int num_leds; /* config */ u8 analog_gain; u8 sensitivity_delta_sense; u8 signal_guard_inputs_mask; u32 thresholds[8]; u32 calib_sensitivities[8]; u32 keycodes[]; }; struct cap11xx_hw_model { u8 product_id; unsigned int num_channels; unsigned int num_leds; bool no_gain; }; enum { CAP1106, CAP1126, CAP1188, CAP1203, CAP1206, CAP1293, CAP1298 }; static const struct cap11xx_hw_model cap11xx_devices[] = { [CAP1106] = { .product_id = 0x55, .num_channels = 6, .num_leds = 0, .no_gain = false }, [CAP1126] = { .product_id = 0x53, .num_channels = 6, .num_leds = 2, .no_gain = false }, [CAP1188] = { .product_id = 0x50, .num_channels = 8, .num_leds = 8, .no_gain = false }, [CAP1203] = { .product_id = 0x6d, .num_channels = 3, .num_leds = 0, .no_gain = true }, [CAP1206] = { .product_id = 0x67, .num_channels = 6, .num_leds = 0, .no_gain = true }, [CAP1293] = { .product_id = 0x6f, .num_channels = 3, .num_leds = 0, .no_gain = false }, [CAP1298] = { .product_id = 0x71, .num_channels = 8, .num_leds = 0, .no_gain = false }, }; static const struct reg_default cap11xx_reg_defaults[] = { { CAP11XX_REG_MAIN_CONTROL, 0x00 }, { CAP11XX_REG_GENERAL_STATUS, 0x00 }, { CAP11XX_REG_SENSOR_INPUT, 0x00 }, { CAP11XX_REG_NOISE_FLAG_STATUS, 0x00 }, { CAP11XX_REG_SENSITIVITY_CONTROL, 0x2f }, { CAP11XX_REG_CONFIG, 0x20 }, { CAP11XX_REG_SENSOR_ENABLE, 0x3f }, { CAP11XX_REG_SENSOR_CONFIG, 0xa4 }, { CAP11XX_REG_SENSOR_CONFIG2, 0x07 }, { CAP11XX_REG_SAMPLING_CONFIG, 0x39 }, { CAP11XX_REG_CALIBRATION, 0x00 }, { CAP11XX_REG_INT_ENABLE, 0x3f }, { CAP11XX_REG_REPEAT_RATE, 0x3f }, { CAP11XX_REG_MT_CONFIG, 0x80 }, { CAP11XX_REG_MT_PATTERN_CONFIG, 0x00 }, { CAP11XX_REG_MT_PATTERN, 0x3f }, { CAP11XX_REG_RECALIB_CONFIG, 0x8a }, { CAP11XX_REG_SENSOR_THRESH(0), 0x40 }, { CAP11XX_REG_SENSOR_THRESH(1), 0x40 }, { CAP11XX_REG_SENSOR_THRESH(2), 0x40 }, { CAP11XX_REG_SENSOR_THRESH(3), 0x40 }, { CAP11XX_REG_SENSOR_THRESH(4), 0x40 }, { CAP11XX_REG_SENSOR_THRESH(5), 0x40 }, { CAP11XX_REG_SENSOR_NOISE_THRESH, 0x01 }, { CAP11XX_REG_STANDBY_CHANNEL, 0x00 }, { CAP11XX_REG_STANDBY_CONFIG, 0x39 }, { CAP11XX_REG_STANDBY_SENSITIVITY, 0x02 }, { CAP11XX_REG_STANDBY_THRESH, 0x40 }, { CAP11XX_REG_CONFIG2, 0x40 }, { CAP11XX_REG_LED_POLARITY, 0x00 }, { CAP11XX_REG_SENSOR_CALIB_LSB1, 0x00 }, { CAP11XX_REG_SENSOR_CALIB_LSB2, 0x00 }, }; static bool cap11xx_volatile_reg(struct device *dev, unsigned int reg) { switch (reg) { case CAP11XX_REG_MAIN_CONTROL: case CAP11XX_REG_SENSOR_INPUT: case CAP11XX_REG_SENOR_DELTA(0): case CAP11XX_REG_SENOR_DELTA(1): case CAP11XX_REG_SENOR_DELTA(2): case CAP11XX_REG_SENOR_DELTA(3): case CAP11XX_REG_SENOR_DELTA(4): case CAP11XX_REG_SENOR_DELTA(5): return true; } return false; } static const struct regmap_config cap11xx_regmap_config = { .reg_bits = 8, .val_bits = 8, .max_register = CAP11XX_REG_REVISION, .reg_defaults = cap11xx_reg_defaults, .num_reg_defaults = ARRAY_SIZE(cap11xx_reg_defaults), .cache_type = REGCACHE_MAPLE, .volatile_reg = cap11xx_volatile_reg, }; static int cap11xx_write_calib_sens_config_1(struct cap11xx_priv *priv) { return regmap_write(priv->regmap, CAP11XX_REG_CALIB_SENSITIVITY_CONFIG, (priv->calib_sensitivities[3] << 6) | (priv->calib_sensitivities[2] << 4) | (priv->calib_sensitivities[1] << 2) | priv->calib_sensitivities[0]); } static int cap11xx_write_calib_sens_config_2(struct cap11xx_priv *priv) { return regmap_write(priv->regmap, CAP11XX_REG_CALIB_SENSITIVITY_CONFIG2, (priv->calib_sensitivities[7] << 6) | (priv->calib_sensitivities[6] << 4) | (priv->calib_sensitivities[5] << 2) | priv->calib_sensitivities[4]); } static int cap11xx_init_keys(struct cap11xx_priv *priv) { struct device_node *node = priv->dev->of_node; struct device *dev = priv->dev; int i, error; u32 u32_val; if (!node) { dev_err(dev, "Corresponding DT entry is not available\n"); return -ENODEV; } if (!of_property_read_u32(node, "microchip,sensor-gain", &u32_val)) { if (priv->model->no_gain) { dev_warn(dev, "This model doesn't support 'sensor-gain'\n"); } else if (is_power_of_2(u32_val) && u32_val <= 8) { priv->analog_gain = (u8)ilog2(u32_val); error = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, CAP11XX_REG_MAIN_CONTROL_GAIN_MASK, priv->analog_gain << CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT); if (error) return error; } else { dev_err(dev, "Invalid sensor-gain value %u\n", u32_val); return -EINVAL; } } if (of_property_read_bool(node, "microchip,irq-active-high")) { if (priv->id == CAP1106 || priv->id == CAP1126 || priv->id == CAP1188) { error = regmap_update_bits(priv->regmap, CAP11XX_REG_CONFIG2, CAP11XX_REG_CONFIG2_ALT_POL, 0); if (error) return error; } else { dev_warn(dev, "This model doesn't support 'irq-active-high'\n"); } } if (!of_property_read_u32(node, "microchip,sensitivity-delta-sense", &u32_val)) { if (!is_power_of_2(u32_val) || u32_val > 128) { dev_err(dev, "Invalid sensitivity-delta-sense value %u\n", u32_val); return -EINVAL; } priv->sensitivity_delta_sense = (u8)ilog2(u32_val); u32_val = ~(FIELD_PREP(CAP11XX_REG_SENSITIVITY_CONTROL_DELTA_SENSE_MASK, priv->sensitivity_delta_sense)); error = regmap_update_bits(priv->regmap, CAP11XX_REG_SENSITIVITY_CONTROL, CAP11XX_REG_SENSITIVITY_CONTROL_DELTA_SENSE_MASK, u32_val); if (error) return error; } if (!of_property_read_u32_array(node, "microchip,input-threshold", priv->thresholds, priv->model->num_channels)) { for (i = 0; i < priv->model->num_channels; i++) { if (priv->thresholds[i] > 127) { dev_err(dev, "Invalid input-threshold value %u\n", priv->thresholds[i]); return -EINVAL; } error = regmap_write(priv->regmap, CAP11XX_REG_SENSOR_THRESH(i), priv->thresholds[i]); if (error) return error; } } if (!of_property_read_u32_array(node, "microchip,calib-sensitivity", priv->calib_sensitivities, priv->model->num_channels)) { if (priv->id == CAP1293 || priv->id == CAP1298) { for (i = 0; i < priv->model->num_channels; i++) { if (!is_power_of_2(priv->calib_sensitivities[i]) || priv->calib_sensitivities[i] > 4) { dev_err(dev, "Invalid calib-sensitivity value %u\n", priv->calib_sensitivities[i]); return -EINVAL; } priv->calib_sensitivities[i] = ilog2(priv->calib_sensitivities[i]); } error = cap11xx_write_calib_sens_config_1(priv); if (error) return error; if (priv->id == CAP1298) { error = cap11xx_write_calib_sens_config_2(priv); if (error) return error; } } else { dev_warn(dev, "This model doesn't support 'calib-sensitivity'\n"); } } for (i = 0; i < priv->model->num_channels; i++) { if (!of_property_read_u32_index(node, "microchip,signal-guard", i, &u32_val)) { if (u32_val > 1) return -EINVAL; if (u32_val) priv->signal_guard_inputs_mask |= 0x01 << i; } } if (priv->signal_guard_inputs_mask) { if (priv->id == CAP1293 || priv->id == CAP1298) { error = regmap_write(priv->regmap, CAP11XX_REG_SIGNAL_GUARD_ENABLE, priv->signal_guard_inputs_mask); if (error) return error; } else { dev_warn(dev, "This model doesn't support 'signal-guard'\n"); } } /* Provide some useful defaults */ for (i = 0; i < priv->model->num_channels; i++) priv->keycodes[i] = KEY_A + i; of_property_read_u32_array(node, "linux,keycodes", priv->keycodes, priv->model->num_channels); /* Disable autorepeat. The Linux input system has its own handling. */ error = regmap_write(priv->regmap, CAP11XX_REG_REPEAT_RATE, 0); if (error) return error; return 0; } static irqreturn_t cap11xx_thread_func(int irq_num, void *data) { struct cap11xx_priv *priv = data; unsigned int status; int ret, i; /* * Deassert interrupt. This needs to be done before reading the status * registers, which will not carry valid values otherwise. */ ret = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, 1, 0); if (ret < 0) goto out; ret = regmap_read(priv->regmap, CAP11XX_REG_SENSOR_INPUT, &status); if (ret < 0) goto out; for (i = 0; i < priv->idev->keycodemax; i++) input_report_key(priv->idev, priv->keycodes[i], status & (1 << i)); input_sync(priv->idev); out: return IRQ_HANDLED; } static int cap11xx_set_sleep(struct cap11xx_priv *priv, bool sleep) { /* * DLSEEP mode will turn off all LEDS, prevent this */ if (IS_ENABLED(CONFIG_LEDS_CLASS) && priv->num_leds) return 0; return regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, CAP11XX_REG_MAIN_CONTROL_DLSEEP, sleep ? CAP11XX_REG_MAIN_CONTROL_DLSEEP : 0); } static int cap11xx_input_open(struct input_dev *idev) { struct cap11xx_priv *priv = input_get_drvdata(idev); return cap11xx_set_sleep(priv, false); } static void cap11xx_input_close(struct input_dev *idev) { struct cap11xx_priv *priv = input_get_drvdata(idev); cap11xx_set_sleep(priv, true); } #ifdef CONFIG_LEDS_CLASS static int cap11xx_led_set(struct led_classdev *cdev, enum led_brightness value) { struct cap11xx_led *led = container_of(cdev, struct cap11xx_led, cdev); struct cap11xx_priv *priv = led->priv; /* * All LEDs share the same duty cycle as this is a HW * limitation. Brightness levels per LED are either * 0 (OFF) and 1 (ON). */ return regmap_update_bits(priv->regmap, CAP11XX_REG_LED_OUTPUT_CONTROL, BIT(led->reg), value ? BIT(led->reg) : 0); } static int cap11xx_init_leds(struct device *dev, struct cap11xx_priv *priv, int num_leds) { struct device_node *node = dev->of_node, *child; struct cap11xx_led *led; int cnt = of_get_child_count(node); int error; if (!num_leds || !cnt) return 0; if (cnt > num_leds) return -EINVAL; led = devm_kcalloc(dev, cnt, sizeof(struct cap11xx_led), GFP_KERNEL); if (!led) return -ENOMEM; priv->leds = led; error = regmap_update_bits(priv->regmap, CAP11XX_REG_LED_OUTPUT_CONTROL, 0xff, 0); if (error) return error; error = regmap_update_bits(priv->regmap, CAP11XX_REG_LED_DUTY_CYCLE_4, CAP11XX_REG_LED_DUTY_MAX_MASK, CAP11XX_REG_LED_DUTY_MAX_VALUE << CAP11XX_REG_LED_DUTY_MAX_MASK_SHIFT); if (error) return error; for_each_child_of_node(node, child) { u32 reg; led->cdev.name = of_get_property(child, "label", NULL) ? : child->name; led->cdev.default_trigger = of_get_property(child, "linux,default-trigger", NULL); led->cdev.flags = 0; led->cdev.brightness_set_blocking = cap11xx_led_set; led->cdev.max_brightness = 1; led->cdev.brightness = LED_OFF; error = of_property_read_u32(child, "reg", ®); if (error != 0 || reg >= num_leds) { of_node_put(child); return -EINVAL; } led->reg = reg; led->priv = priv; error = devm_led_classdev_register(dev, &led->cdev); if (error) { of_node_put(child); return error; } priv->num_leds++; led++; } return 0; } #else static int cap11xx_init_leds(struct device *dev, struct cap11xx_priv *priv, int num_leds) { return 0; } #endif static int cap11xx_i2c_probe(struct i2c_client *i2c_client) { const struct i2c_device_id *id = i2c_client_get_device_id(i2c_client); struct device *dev = &i2c_client->dev; struct cap11xx_priv *priv; const struct cap11xx_hw_model *cap; int i, error; unsigned int val, rev; if (id->driver_data >= ARRAY_SIZE(cap11xx_devices)) { dev_err(dev, "Invalid device ID %lu\n", id->driver_data); return -EINVAL; } cap = &cap11xx_devices[id->driver_data]; if (!cap || !cap->num_channels) { dev_err(dev, "Invalid device configuration\n"); return -EINVAL; } priv = devm_kzalloc(dev, struct_size(priv, keycodes, cap->num_channels), GFP_KERNEL); if (!priv) return -ENOMEM; priv->dev = dev; priv->regmap = devm_regmap_init_i2c(i2c_client, &cap11xx_regmap_config); if (IS_ERR(priv->regmap)) return PTR_ERR(priv->regmap); error = regmap_read(priv->regmap, CAP11XX_REG_PRODUCT_ID, &val); if (error) return error; if (val != cap->product_id) { dev_err(dev, "Product ID: Got 0x%02x, expected 0x%02x\n", val, cap->product_id); return -ENXIO; } error = regmap_read(priv->regmap, CAP11XX_REG_MANUFACTURER_ID, &val); if (error) return error; if (val != CAP11XX_MANUFACTURER_ID) { dev_err(dev, "Manufacturer ID: Got 0x%02x, expected 0x%02x\n", val, CAP11XX_MANUFACTURER_ID); return -ENXIO; } error = regmap_read(priv->regmap, CAP11XX_REG_REVISION, &rev); if (error < 0) return error; dev_info(dev, "CAP11XX detected, model %s, revision 0x%02x\n", id->name, rev); priv->model = cap; priv->id = id->driver_data; dev_info(dev, "CAP11XX device detected, model %s, revision 0x%02x\n", id->name, rev); error = cap11xx_init_keys(priv); if (error) return error; priv->idev = devm_input_allocate_device(dev); if (!priv->idev) return -ENOMEM; priv->idev->name = "CAP11XX capacitive touch sensor"; priv->idev->id.bustype = BUS_I2C; priv->idev->evbit[0] = BIT_MASK(EV_KEY); if (of_property_read_bool(dev->of_node, "autorepeat")) __set_bit(EV_REP, priv->idev->evbit); for (i = 0; i < cap->num_channels; i++) __set_bit(priv->keycodes[i], priv->idev->keybit); __clear_bit(KEY_RESERVED, priv->idev->keybit); priv->idev->keycode = priv->keycodes; priv->idev->keycodesize = sizeof(priv->keycodes[0]); priv->idev->keycodemax = cap->num_channels; priv->idev->id.vendor = CAP11XX_MANUFACTURER_ID; priv->idev->id.product = cap->product_id; priv->idev->id.version = rev; priv->idev->open = cap11xx_input_open; priv->idev->close = cap11xx_input_close; error = cap11xx_init_leds(dev, priv, cap->num_leds); if (error) return error; input_set_drvdata(priv->idev, priv); /* * Put the device in deep sleep mode for now. * ->open() will bring it back once the it is actually needed. */ cap11xx_set_sleep(priv, true); error = input_register_device(priv->idev); if (error) return error; error = devm_request_threaded_irq(dev, i2c_client->irq, NULL, cap11xx_thread_func, IRQF_ONESHOT, dev_name(dev), priv); if (error) return error; return 0; } static const struct of_device_id cap11xx_dt_ids[] = { { .compatible = "microchip,cap1106", }, { .compatible = "microchip,cap1126", }, { .compatible = "microchip,cap1188", }, { .compatible = "microchip,cap1203", }, { .compatible = "microchip,cap1206", }, { .compatible = "microchip,cap1293", }, { .compatible = "microchip,cap1298", }, {} }; MODULE_DEVICE_TABLE(of, cap11xx_dt_ids); static const struct i2c_device_id cap11xx_i2c_ids[] = { { "cap1106", CAP1106 }, { "cap1126", CAP1126 }, { "cap1188", CAP1188 }, { "cap1203", CAP1203 }, { "cap1206", CAP1206 }, { "cap1293", CAP1293 }, { "cap1298", CAP1298 }, {} }; MODULE_DEVICE_TABLE(i2c, cap11xx_i2c_ids); static struct i2c_driver cap11xx_i2c_driver = { .driver = { .name = "cap11xx", .of_match_table = cap11xx_dt_ids, }, .id_table = cap11xx_i2c_ids, .probe = cap11xx_i2c_probe, }; module_i2c_driver(cap11xx_i2c_driver); MODULE_DESCRIPTION("Microchip CAP11XX driver"); MODULE_AUTHOR("Daniel Mack "); MODULE_LICENSE("GPL v2");