// 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 #include #include #define CAP1114_REG_BUTTON_STATUS1 0x03 #define CAP1114_REG_BUTTON_STATUS2 0x04 #define CAP1114_REG_CONFIG2 0x40 #define CAP1114_REG_CONFIG2_VOL_UP_DOWN BIT(1) #define CAP1114_REG_LED_OUTPUT_CONTROL1 0x73 #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_SENSOR_INPUT 0x03 #define CAP1114_REG_BUTTON_STATUS2 0x04 #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_REPEAT_RATE 0x28 #define CAP11XX_REG_SIGNAL_GUARD_ENABLE 0x29 #define CAP11XX_REG_SENSOR_THRESH(X) (0x30 + (X)) #define CAP11XX_REG_CONFIG2 0x44 #define CAP11XX_REG_CONFIG2_ALT_POL BIT(6) #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_4 0x93 #define CAP11XX_REG_LED_DUTY_MAX_MASK (0xf0) #define CAP11XX_REG_LED_DUTY_MAX_VALUE (15) #define CAP11XX_REG_PRODUCT_ID 0xfd #define CAP11XX_REG_MANUFACTURER_ID 0xfe #define CAP11XX_REG_REVISION 0xff #define CAP11XX_MANUFACTURER_ID 0x5d #define CAP11XX_T_RST_FILT_MIN_US 10000 #define CAP11XX_T_RST_ON_MIN_MS 400 #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; struct gpio_desc *reset_gpio; const struct cap11xx_hw_model *model; 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; u8 led_output_control_reg_base; u8 sensor_input_reg_base; unsigned int num_channels; unsigned int num_leds; unsigned int num_sensor_thresholds; bool has_gain; bool has_grouped_sensors; bool has_irq_config; bool has_repeat_en; bool has_sensitivity_control; bool has_signal_guard; }; static const struct reg_default cap11xx_reg_defaults[] = { { CAP11XX_REG_MAIN_CONTROL, 0x00 }, { CAP11XX_REG_SENSITIVITY_CONTROL, 0x2f }, { CAP11XX_REG_REPEAT_RATE, 0x3f }, { 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_THRESH(6), 0x40 }, { CAP11XX_REG_SENSOR_THRESH(7), 0x40 }, { CAP11XX_REG_CONFIG2, 0x40 }, }; static bool cap11xx_volatile_reg(struct device *dev, unsigned int reg) { switch (reg) { case CAP11XX_REG_MAIN_CONTROL: case CAP11XX_REG_SENSOR_INPUT: /* * CAP1114_REG_BUTTON_STATUS1 (CAP11XX_REG_SENSOR_INPUT) and * CAP1114_REG_BUTTON_STATUS2 is volatile for the CAP1114, * which supports more than 8 touch channels. */ case CAP1114_REG_BUTTON_STATUS2: 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->has_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->model->has_irq_config) { 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_sensor_thresholds)) { for (i = 0; i < priv->model->num_sensor_thresholds; 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_present(node, "microchip,calib-sensitivity")) { if (!priv->model->has_sensitivity_control) { dev_warn(dev, "This model doesn't support 'calib-sensitivity'\n"); } else if (!of_property_read_u32_array(node, "microchip,calib-sensitivity", priv->calib_sensitivities, priv->model->num_channels)) { 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->model->num_channels > 4) { error = cap11xx_write_calib_sens_config_2(priv); if (error) return error; } } } if (of_property_present(node, "microchip,signal-guard")) { if (!priv->model->has_signal_guard) { dev_warn(dev, "This model doesn't support 'signal-guard'\n"); } else { 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) { error = regmap_write(priv->regmap, CAP11XX_REG_SIGNAL_GUARD_ENABLE, priv->signal_guard_inputs_mask); if (error) return error; } } } /* 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); /* * CAP1114 needs dedicated configuration to split * grouped sensors into independent inputs. */ if (priv->model->has_grouped_sensors) { error = regmap_set_bits(priv->regmap, CAP1114_REG_CONFIG2, CAP1114_REG_CONFIG2_VOL_UP_DOWN); if (error) return error; } if (priv->model->has_repeat_en) { /* 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, priv->model->sensor_input_reg_base, &status); if (ret < 0) goto out; if (priv->model->num_channels > 8) { unsigned int status2; ret = regmap_read(priv->regmap, priv->model->sensor_input_reg_base + 1, &status2); if (ret < 0) goto out; /* * CAP1114 STATUS1 register only contains data for the first 6 channels. * the remaining channels is stored in STATUS2. */ status &= GENMASK(5, 0); status |= FIELD_PREP(GENMASK(13, 6), status2); } 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). */ if (led->reg >= 8) return regmap_update_bits(priv->regmap, priv->model->led_output_control_reg_base + 1, BIT(led->reg - 8), value ? BIT(led->reg - 8) : 0); else return regmap_update_bits(priv->regmap, priv->model->led_output_control_reg_base, 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; struct cap11xx_led *led; int cnt = of_get_child_count(node); int error; u32 duty_val; 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; /* Set all LEDs to off */ error = regmap_update_bits(priv->regmap, priv->model->led_output_control_reg_base, GENMASK(min(num_leds, 8) - 1, 0), 0); if (error) return error; if (num_leds > 8) { error = regmap_update_bits(priv->regmap, priv->model->led_output_control_reg_base + 1, GENMASK(num_leds - 8 - 1, 0), 0); if (error) return error; } duty_val = FIELD_PREP(CAP11XX_REG_LED_DUTY_MAX_MASK, CAP11XX_REG_LED_DUTY_MAX_VALUE); error = regmap_update_bits(priv->regmap, CAP11XX_REG_LED_DUTY_CYCLE_4, CAP11XX_REG_LED_DUTY_MAX_MASK, duty_val); if (error) return error; for_each_child_of_node_scoped(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) return -EINVAL; led->reg = reg; led->priv = priv; error = devm_led_classdev_register(dev, &led->cdev); if (error) 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; const struct cap11xx_hw_model *cap; struct device *dev = &i2c_client->dev; struct cap11xx_priv *priv; int i, error; unsigned int val, rev; id = i2c_client_get_device_id(i2c_client); cap = i2c_get_match_data(i2c_client); if (!id || !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); priv->reset_gpio = devm_gpiod_get_optional(dev, "reset", GPIOD_OUT_HIGH); if (IS_ERR(priv->reset_gpio)) return dev_err_probe(dev, PTR_ERR(priv->reset_gpio), "Failed to get 'reset' GPIO\n"); if (priv->reset_gpio) { usleep_range(CAP11XX_T_RST_FILT_MIN_US, CAP11XX_T_RST_FILT_MIN_US * 2); gpiod_set_value_cansleep(priv->reset_gpio, 0); msleep(CAP11XX_T_RST_ON_MIN_MS); } error = regmap_read(priv->regmap, CAP11XX_REG_PRODUCT_ID, &val); if (error) return dev_err_probe(dev, error, "Failed to read product ID\n"); 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 dev_err_probe(dev, error, "Failed to read manufacturer ID\n"); 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) return dev_err_probe(dev, error, "Failed to read revision\n"); priv->model = cap; 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 cap11xx_hw_model cap1106_model = { .product_id = 0x55, .num_channels = 6, .num_leds = 0, .num_sensor_thresholds = 6, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_gain = true, .has_irq_config = true, .has_repeat_en = true, }; static const struct cap11xx_hw_model cap1114_model = { .product_id = 0x3a, .num_channels = 14, .num_leds = 11, .num_sensor_thresholds = 8, .led_output_control_reg_base = CAP1114_REG_LED_OUTPUT_CONTROL1, .sensor_input_reg_base = CAP1114_REG_BUTTON_STATUS1, .has_grouped_sensors = true, }; static const struct cap11xx_hw_model cap1126_model = { .product_id = 0x53, .num_channels = 6, .num_leds = 2, .num_sensor_thresholds = 6, .led_output_control_reg_base = CAP11XX_REG_LED_OUTPUT_CONTROL, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_gain = true, .has_irq_config = true, .has_repeat_en = true, }; static const struct cap11xx_hw_model cap1188_model = { .product_id = 0x50, .num_channels = 8, .num_leds = 8, .num_sensor_thresholds = 8, .led_output_control_reg_base = CAP11XX_REG_LED_OUTPUT_CONTROL, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_gain = true, .has_irq_config = true, .has_repeat_en = true, }; static const struct cap11xx_hw_model cap1203_model = { .product_id = 0x6d, .num_channels = 3, .num_leds = 0, .num_sensor_thresholds = 3, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_repeat_en = true, }; static const struct cap11xx_hw_model cap1206_model = { .product_id = 0x67, .num_channels = 6, .num_leds = 0, .num_sensor_thresholds = 6, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_repeat_en = true, }; static const struct cap11xx_hw_model cap1293_model = { .product_id = 0x6f, .num_channels = 3, .num_leds = 0, .num_sensor_thresholds = 3, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_gain = true, .has_repeat_en = true, .has_sensitivity_control = true, .has_signal_guard = true, }; static const struct cap11xx_hw_model cap1298_model = { .product_id = 0x71, .num_channels = 8, .num_leds = 0, .num_sensor_thresholds = 8, .sensor_input_reg_base = CAP11XX_REG_SENSOR_INPUT, .has_gain = true, .has_repeat_en = true, .has_sensitivity_control = true, .has_signal_guard = true, }; static const struct of_device_id cap11xx_dt_ids[] = { { .compatible = "microchip,cap1106", .data = &cap1106_model }, { .compatible = "microchip,cap1114", .data = &cap1114_model }, { .compatible = "microchip,cap1126", .data = &cap1126_model }, { .compatible = "microchip,cap1188", .data = &cap1188_model }, { .compatible = "microchip,cap1203", .data = &cap1203_model }, { .compatible = "microchip,cap1206", .data = &cap1206_model }, { .compatible = "microchip,cap1293", .data = &cap1293_model }, { .compatible = "microchip,cap1298", .data = &cap1298_model }, { } }; MODULE_DEVICE_TABLE(of, cap11xx_dt_ids); static const struct i2c_device_id cap11xx_i2c_ids[] = { { .name = "cap1106", .driver_data = (kernel_ulong_t)&cap1106_model }, { .name = "cap1114", .driver_data = (kernel_ulong_t)&cap1114_model }, { .name = "cap1126", .driver_data = (kernel_ulong_t)&cap1126_model }, { .name = "cap1188", .driver_data = (kernel_ulong_t)&cap1188_model }, { .name = "cap1203", .driver_data = (kernel_ulong_t)&cap1203_model }, { .name = "cap1206", .driver_data = (kernel_ulong_t)&cap1206_model }, { .name = "cap1293", .driver_data = (kernel_ulong_t)&cap1293_model }, { .name = "cap1298", .driver_data = (kernel_ulong_t)&cap1298_model }, { } }; 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");