| /* |
| * Input driver for Microchip CAP11xx based capacitive touch sensors |
| * |
| * (c) 2014 Daniel Mack <linux@zonque.org> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| */ |
| |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/interrupt.h> |
| #include <linux/input.h> |
| #include <linux/of_irq.h> |
| #include <linux/regmap.h> |
| #include <linux/i2c.h> |
| #include <linux/gpio/consumer.h> |
| |
| #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_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_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_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 |
| |
| struct cap11xx_priv { |
| struct regmap *regmap; |
| struct input_dev *idev; |
| |
| /* config */ |
| u32 keycodes[]; |
| }; |
| |
| struct cap11xx_hw_model { |
| u8 product_id; |
| unsigned int num_channels; |
| }; |
| |
| enum { |
| CAP1106, |
| CAP1126, |
| CAP1188, |
| }; |
| |
| static const struct cap11xx_hw_model cap11xx_devices[] = { |
| [CAP1106] = { .product_id = 0x55, .num_channels = 6 }, |
| [CAP1126] = { .product_id = 0x53, .num_channels = 6 }, |
| [CAP1188] = { .product_id = 0x50, .num_channels = 8 }, |
| }; |
| |
| 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_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): |
| case CAP11XX_REG_PRODUCT_ID: |
| case CAP11XX_REG_MANUFACTURER_ID: |
| case CAP11XX_REG_REVISION: |
| 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_RBTREE, |
| .volatile_reg = cap11xx_volatile_reg, |
| }; |
| |
| 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) |
| { |
| 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); |
| } |
| |
| static int cap11xx_i2c_probe(struct i2c_client *i2c_client, |
| const struct i2c_device_id *id) |
| { |
| struct device *dev = &i2c_client->dev; |
| struct cap11xx_priv *priv; |
| struct device_node *node; |
| const struct cap11xx_hw_model *cap; |
| int i, error, irq, gain = 0; |
| unsigned int val, rev; |
| u32 gain32; |
| |
| 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, |
| sizeof(*priv) + |
| cap->num_channels * sizeof(priv->keycodes[0]), |
| GFP_KERNEL); |
| if (!priv) |
| return -ENOMEM; |
| |
| 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, revision 0x%02x\n", rev); |
| i2c_set_clientdata(i2c_client, priv); |
| node = dev->of_node; |
| |
| if (!of_property_read_u32(node, "microchip,sensor-gain", &gain32)) { |
| if (is_power_of_2(gain32) && gain32 <= 8) |
| gain = ilog2(gain32); |
| else |
| dev_err(dev, "Invalid sensor-gain value %d\n", gain32); |
| } |
| |
| if (of_property_read_bool(node, "microchip,irq-active-high")) { |
| error = regmap_update_bits(priv->regmap, CAP11XX_REG_CONFIG2, |
| CAP11XX_REG_CONFIG2_ALT_POL, 0); |
| if (error) |
| return error; |
| } |
| |
| /* Provide some useful defaults */ |
| for (i = 0; i < cap->num_channels; i++) |
| priv->keycodes[i] = KEY_A + i; |
| |
| of_property_read_u32_array(node, "linux,keycodes", |
| priv->keycodes, cap->num_channels); |
| |
| error = regmap_update_bits(priv->regmap, CAP11XX_REG_MAIN_CONTROL, |
| CAP11XX_REG_MAIN_CONTROL_GAIN_MASK, |
| gain << CAP11XX_REG_MAIN_CONTROL_GAIN_SHIFT); |
| if (error) |
| return error; |
| |
| /* Disable autorepeat. The Linux input system has its own handling. */ |
| error = regmap_write(priv->regmap, CAP11XX_REG_REPEAT_RATE, 0); |
| 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(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; |
| |
| 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; |
| |
| irq = irq_of_parse_and_map(node, 0); |
| if (!irq) { |
| dev_err(dev, "Unable to parse or map IRQ\n"); |
| return -ENXIO; |
| } |
| |
| error = devm_request_threaded_irq(dev, 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", }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(of, cap11xx_dt_ids); |
| |
| static const struct i2c_device_id cap11xx_i2c_ids[] = { |
| { "cap1106", CAP1106 }, |
| { "cap1126", CAP1126 }, |
| { "cap1188", CAP1188 }, |
| {} |
| }; |
| MODULE_DEVICE_TABLE(i2c, cap11xx_i2c_ids); |
| |
| static struct i2c_driver cap11xx_i2c_driver = { |
| .driver = { |
| .name = "cap11xx", |
| .owner = THIS_MODULE, |
| .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 <linux@zonque.org>"); |
| MODULE_LICENSE("GPL v2"); |