diff options
Diffstat (limited to 'drivers/input/misc/ad714x.c')
| -rw-r--r-- | drivers/input/misc/ad714x.c | 1209 |
1 files changed, 1209 insertions, 0 deletions
diff --git a/drivers/input/misc/ad714x.c b/drivers/input/misc/ad714x.c new file mode 100644 index 000000000..43132d98f --- /dev/null +++ b/drivers/input/misc/ad714x.c @@ -0,0 +1,1209 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * AD714X CapTouch Programmable Controller driver supporting AD7142/3/7/8/7A + * + * Copyright 2009-2011 Analog Devices Inc. + */ + +#include <linux/device.h> +#include <linux/input.h> +#include <linux/interrupt.h> +#include <linux/slab.h> +#include <linux/input/ad714x.h> +#include <linux/module.h> +#include "ad714x.h" + +#define AD714X_PWR_CTRL 0x0 +#define AD714X_STG_CAL_EN_REG 0x1 +#define AD714X_AMB_COMP_CTRL0_REG 0x2 +#define AD714X_PARTID_REG 0x17 +#define AD7142_PARTID 0xE620 +#define AD7143_PARTID 0xE630 +#define AD7147_PARTID 0x1470 +#define AD7148_PARTID 0x1480 +#define AD714X_STAGECFG_REG 0x80 +#define AD714X_SYSCFG_REG 0x0 + +#define STG_LOW_INT_EN_REG 0x5 +#define STG_HIGH_INT_EN_REG 0x6 +#define STG_COM_INT_EN_REG 0x7 +#define STG_LOW_INT_STA_REG 0x8 +#define STG_HIGH_INT_STA_REG 0x9 +#define STG_COM_INT_STA_REG 0xA + +#define CDC_RESULT_S0 0xB +#define CDC_RESULT_S1 0xC +#define CDC_RESULT_S2 0xD +#define CDC_RESULT_S3 0xE +#define CDC_RESULT_S4 0xF +#define CDC_RESULT_S5 0x10 +#define CDC_RESULT_S6 0x11 +#define CDC_RESULT_S7 0x12 +#define CDC_RESULT_S8 0x13 +#define CDC_RESULT_S9 0x14 +#define CDC_RESULT_S10 0x15 +#define CDC_RESULT_S11 0x16 + +#define STAGE0_AMBIENT 0xF1 +#define STAGE1_AMBIENT 0x115 +#define STAGE2_AMBIENT 0x139 +#define STAGE3_AMBIENT 0x15D +#define STAGE4_AMBIENT 0x181 +#define STAGE5_AMBIENT 0x1A5 +#define STAGE6_AMBIENT 0x1C9 +#define STAGE7_AMBIENT 0x1ED +#define STAGE8_AMBIENT 0x211 +#define STAGE9_AMBIENT 0x234 +#define STAGE10_AMBIENT 0x259 +#define STAGE11_AMBIENT 0x27D + +#define PER_STAGE_REG_NUM 36 +#define STAGE_CFGREG_NUM 8 +#define SYS_CFGREG_NUM 8 + +/* + * driver information which will be used to maintain the software flow + */ +enum ad714x_device_state { IDLE, JITTER, ACTIVE, SPACE }; + +struct ad714x_slider_drv { + int highest_stage; + int abs_pos; + int flt_pos; + enum ad714x_device_state state; + struct input_dev *input; +}; + +struct ad714x_wheel_drv { + int abs_pos; + int flt_pos; + int pre_highest_stage; + int highest_stage; + enum ad714x_device_state state; + struct input_dev *input; +}; + +struct ad714x_touchpad_drv { + int x_highest_stage; + int x_flt_pos; + int x_abs_pos; + int y_highest_stage; + int y_flt_pos; + int y_abs_pos; + int left_ep; + int left_ep_val; + int right_ep; + int right_ep_val; + int top_ep; + int top_ep_val; + int bottom_ep; + int bottom_ep_val; + enum ad714x_device_state state; + struct input_dev *input; +}; + +struct ad714x_button_drv { + enum ad714x_device_state state; + /* + * Unlike slider/wheel/touchpad, all buttons point to + * same input_dev instance + */ + struct input_dev *input; +}; + +struct ad714x_driver_data { + struct ad714x_slider_drv *slider; + struct ad714x_wheel_drv *wheel; + struct ad714x_touchpad_drv *touchpad; + struct ad714x_button_drv *button; +}; + +/* + * information to integrate all things which will be private data + * of spi/i2c device + */ + +static void ad714x_use_com_int(struct ad714x_chip *ad714x, + int start_stage, int end_stage) +{ + unsigned short data; + unsigned short mask; + + mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1); + + ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1); + data |= 1 << end_stage; + ad714x->write(ad714x, STG_COM_INT_EN_REG, data); + + ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1); + data &= ~mask; + ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data); +} + +static void ad714x_use_thr_int(struct ad714x_chip *ad714x, + int start_stage, int end_stage) +{ + unsigned short data; + unsigned short mask; + + mask = ((1 << (end_stage + 1)) - 1) - ((1 << start_stage) - 1); + + ad714x->read(ad714x, STG_COM_INT_EN_REG, &data, 1); + data &= ~(1 << end_stage); + ad714x->write(ad714x, STG_COM_INT_EN_REG, data); + + ad714x->read(ad714x, STG_HIGH_INT_EN_REG, &data, 1); + data |= mask; + ad714x->write(ad714x, STG_HIGH_INT_EN_REG, data); +} + +static int ad714x_cal_highest_stage(struct ad714x_chip *ad714x, + int start_stage, int end_stage) +{ + int max_res = 0; + int max_idx = 0; + int i; + + for (i = start_stage; i <= end_stage; i++) { + if (ad714x->sensor_val[i] > max_res) { + max_res = ad714x->sensor_val[i]; + max_idx = i; + } + } + + return max_idx; +} + +static int ad714x_cal_abs_pos(struct ad714x_chip *ad714x, + int start_stage, int end_stage, + int highest_stage, int max_coord) +{ + int a_param, b_param; + + if (highest_stage == start_stage) { + a_param = ad714x->sensor_val[start_stage + 1]; + b_param = ad714x->sensor_val[start_stage] + + ad714x->sensor_val[start_stage + 1]; + } else if (highest_stage == end_stage) { + a_param = ad714x->sensor_val[end_stage] * + (end_stage - start_stage) + + ad714x->sensor_val[end_stage - 1] * + (end_stage - start_stage - 1); + b_param = ad714x->sensor_val[end_stage] + + ad714x->sensor_val[end_stage - 1]; + } else { + a_param = ad714x->sensor_val[highest_stage] * + (highest_stage - start_stage) + + ad714x->sensor_val[highest_stage - 1] * + (highest_stage - start_stage - 1) + + ad714x->sensor_val[highest_stage + 1] * + (highest_stage - start_stage + 1); + b_param = ad714x->sensor_val[highest_stage] + + ad714x->sensor_val[highest_stage - 1] + + ad714x->sensor_val[highest_stage + 1]; + } + + return (max_coord / (end_stage - start_stage)) * a_param / b_param; +} + +/* + * One button can connect to multi positive and negative of CDCs + * Multi-buttons can connect to same positive/negative of one CDC + */ +static void ad714x_button_state_machine(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_button_plat *hw = &ad714x->hw->button[idx]; + struct ad714x_button_drv *sw = &ad714x->sw->button[idx]; + + switch (sw->state) { + case IDLE: + if (((ad714x->h_state & hw->h_mask) == hw->h_mask) && + ((ad714x->l_state & hw->l_mask) == hw->l_mask)) { + dev_dbg(ad714x->dev, "button %d touched\n", idx); + input_report_key(sw->input, hw->keycode, 1); + input_sync(sw->input); + sw->state = ACTIVE; + } + break; + + case ACTIVE: + if (((ad714x->h_state & hw->h_mask) != hw->h_mask) || + ((ad714x->l_state & hw->l_mask) != hw->l_mask)) { + dev_dbg(ad714x->dev, "button %d released\n", idx); + input_report_key(sw->input, hw->keycode, 0); + input_sync(sw->input); + sw->state = IDLE; + } + break; + + default: + break; + } +} + +/* + * The response of a sensor is defined by the absolute number of codes + * between the current CDC value and the ambient value. + */ +static void ad714x_slider_cal_sensor_val(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx]; + int i; + + ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage, + &ad714x->adc_reg[hw->start_stage], + hw->end_stage - hw->start_stage + 1); + + for (i = hw->start_stage; i <= hw->end_stage; i++) { + ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM, + &ad714x->amb_reg[i], 1); + + ad714x->sensor_val[i] = + abs(ad714x->adc_reg[i] - ad714x->amb_reg[i]); + } +} + +static void ad714x_slider_cal_highest_stage(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx]; + struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx]; + + sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage, + hw->end_stage); + + dev_dbg(ad714x->dev, "slider %d highest_stage:%d\n", idx, + sw->highest_stage); +} + +/* + * The formulae are very straight forward. It uses the sensor with the + * highest response and the 2 adjacent ones. + * When Sensor 0 has the highest response, only sensor 0 and sensor 1 + * are used in the calculations. Similarly when the last sensor has the + * highest response, only the last sensor and the second last sensors + * are used in the calculations. + * + * For i= idx_of_peak_Sensor-1 to i= idx_of_peak_Sensor+1 + * v += Sensor response(i)*i + * w += Sensor response(i) + * POS=(Number_of_Positions_Wanted/(Number_of_Sensors_Used-1)) *(v/w) + */ +static void ad714x_slider_cal_abs_pos(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx]; + struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx]; + + sw->abs_pos = ad714x_cal_abs_pos(ad714x, hw->start_stage, hw->end_stage, + sw->highest_stage, hw->max_coord); + + dev_dbg(ad714x->dev, "slider %d absolute position:%d\n", idx, + sw->abs_pos); +} + +/* + * To minimise the Impact of the noise on the algorithm, ADI developed a + * routine that filters the CDC results after they have been read by the + * host processor. + * The filter used is an Infinite Input Response(IIR) filter implemented + * in firmware and attenuates the noise on the CDC results after they've + * been read by the host processor. + * Filtered_CDC_result = (Filtered_CDC_result * (10 - Coefficient) + + * Latest_CDC_result * Coefficient)/10 + */ +static void ad714x_slider_cal_flt_pos(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx]; + + sw->flt_pos = (sw->flt_pos * (10 - 4) + + sw->abs_pos * 4)/10; + + dev_dbg(ad714x->dev, "slider %d filter position:%d\n", idx, + sw->flt_pos); +} + +static void ad714x_slider_use_com_int(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx]; + + ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage); +} + +static void ad714x_slider_use_thr_int(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx]; + + ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage); +} + +static void ad714x_slider_state_machine(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_slider_plat *hw = &ad714x->hw->slider[idx]; + struct ad714x_slider_drv *sw = &ad714x->sw->slider[idx]; + unsigned short h_state, c_state; + unsigned short mask; + + mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1); + + h_state = ad714x->h_state & mask; + c_state = ad714x->c_state & mask; + + switch (sw->state) { + case IDLE: + if (h_state) { + sw->state = JITTER; + /* In End of Conversion interrupt mode, the AD714X + * continuously generates hardware interrupts. + */ + ad714x_slider_use_com_int(ad714x, idx); + dev_dbg(ad714x->dev, "slider %d touched\n", idx); + } + break; + + case JITTER: + if (c_state == mask) { + ad714x_slider_cal_sensor_val(ad714x, idx); + ad714x_slider_cal_highest_stage(ad714x, idx); + ad714x_slider_cal_abs_pos(ad714x, idx); + sw->flt_pos = sw->abs_pos; + sw->state = ACTIVE; + } + break; + + case ACTIVE: + if (c_state == mask) { + if (h_state) { + ad714x_slider_cal_sensor_val(ad714x, idx); + ad714x_slider_cal_highest_stage(ad714x, idx); + ad714x_slider_cal_abs_pos(ad714x, idx); + ad714x_slider_cal_flt_pos(ad714x, idx); + input_report_abs(sw->input, ABS_X, sw->flt_pos); + input_report_key(sw->input, BTN_TOUCH, 1); + } else { + /* When the user lifts off the sensor, configure + * the AD714X back to threshold interrupt mode. + */ + ad714x_slider_use_thr_int(ad714x, idx); + sw->state = IDLE; + input_report_key(sw->input, BTN_TOUCH, 0); + dev_dbg(ad714x->dev, "slider %d released\n", + idx); + } + input_sync(sw->input); + } + break; + + default: + break; + } +} + +/* + * When the scroll wheel is activated, we compute the absolute position based + * on the sensor values. To calculate the position, we first determine the + * sensor that has the greatest response among the 8 sensors that constitutes + * the scrollwheel. Then we determined the 2 sensors on either sides of the + * sensor with the highest response and we apply weights to these sensors. + */ +static void ad714x_wheel_cal_highest_stage(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx]; + + sw->pre_highest_stage = sw->highest_stage; + sw->highest_stage = ad714x_cal_highest_stage(ad714x, hw->start_stage, + hw->end_stage); + + dev_dbg(ad714x->dev, "wheel %d highest_stage:%d\n", idx, + sw->highest_stage); +} + +static void ad714x_wheel_cal_sensor_val(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + int i; + + ad714x->read(ad714x, CDC_RESULT_S0 + hw->start_stage, + &ad714x->adc_reg[hw->start_stage], + hw->end_stage - hw->start_stage + 1); + + for (i = hw->start_stage; i <= hw->end_stage; i++) { + ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM, + &ad714x->amb_reg[i], 1); + if (ad714x->adc_reg[i] > ad714x->amb_reg[i]) + ad714x->sensor_val[i] = + ad714x->adc_reg[i] - ad714x->amb_reg[i]; + else + ad714x->sensor_val[i] = 0; + } +} + +/* + * When the scroll wheel is activated, we compute the absolute position based + * on the sensor values. To calculate the position, we first determine the + * sensor that has the greatest response among the sensors that constitutes + * the scrollwheel. Then we determined the sensors on either sides of the + * sensor with the highest response and we apply weights to these sensors. The + * result of this computation gives us the mean value. + */ + +static void ad714x_wheel_cal_abs_pos(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx]; + int stage_num = hw->end_stage - hw->start_stage + 1; + int first_before, highest, first_after; + int a_param, b_param; + + first_before = (sw->highest_stage + stage_num - 1) % stage_num; + highest = sw->highest_stage; + first_after = (sw->highest_stage + stage_num + 1) % stage_num; + + a_param = ad714x->sensor_val[highest] * + (highest - hw->start_stage) + + ad714x->sensor_val[first_before] * + (highest - hw->start_stage - 1) + + ad714x->sensor_val[first_after] * + (highest - hw->start_stage + 1); + b_param = ad714x->sensor_val[highest] + + ad714x->sensor_val[first_before] + + ad714x->sensor_val[first_after]; + + sw->abs_pos = ((hw->max_coord / (hw->end_stage - hw->start_stage)) * + a_param) / b_param; + + if (sw->abs_pos > hw->max_coord) + sw->abs_pos = hw->max_coord; + else if (sw->abs_pos < 0) + sw->abs_pos = 0; +} + +static void ad714x_wheel_cal_flt_pos(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx]; + if (((sw->pre_highest_stage == hw->end_stage) && + (sw->highest_stage == hw->start_stage)) || + ((sw->pre_highest_stage == hw->start_stage) && + (sw->highest_stage == hw->end_stage))) + sw->flt_pos = sw->abs_pos; + else + sw->flt_pos = ((sw->flt_pos * 30) + (sw->abs_pos * 71)) / 100; + + if (sw->flt_pos > hw->max_coord) + sw->flt_pos = hw->max_coord; +} + +static void ad714x_wheel_use_com_int(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + + ad714x_use_com_int(ad714x, hw->start_stage, hw->end_stage); +} + +static void ad714x_wheel_use_thr_int(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + + ad714x_use_thr_int(ad714x, hw->start_stage, hw->end_stage); +} + +static void ad714x_wheel_state_machine(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_wheel_plat *hw = &ad714x->hw->wheel[idx]; + struct ad714x_wheel_drv *sw = &ad714x->sw->wheel[idx]; + unsigned short h_state, c_state; + unsigned short mask; + + mask = ((1 << (hw->end_stage + 1)) - 1) - ((1 << hw->start_stage) - 1); + + h_state = ad714x->h_state & mask; + c_state = ad714x->c_state & mask; + + switch (sw->state) { + case IDLE: + if (h_state) { + sw->state = JITTER; + /* In End of Conversion interrupt mode, the AD714X + * continuously generates hardware interrupts. + */ + ad714x_wheel_use_com_int(ad714x, idx); + dev_dbg(ad714x->dev, "wheel %d touched\n", idx); + } + break; + + case JITTER: + if (c_state == mask) { + ad714x_wheel_cal_sensor_val(ad714x, idx); + ad714x_wheel_cal_highest_stage(ad714x, idx); + ad714x_wheel_cal_abs_pos(ad714x, idx); + sw->flt_pos = sw->abs_pos; + sw->state = ACTIVE; + } + break; + + case ACTIVE: + if (c_state == mask) { + if (h_state) { + ad714x_wheel_cal_sensor_val(ad714x, idx); + ad714x_wheel_cal_highest_stage(ad714x, idx); + ad714x_wheel_cal_abs_pos(ad714x, idx); + ad714x_wheel_cal_flt_pos(ad714x, idx); + input_report_abs(sw->input, ABS_WHEEL, + sw->flt_pos); + input_report_key(sw->input, BTN_TOUCH, 1); + } else { + /* When the user lifts off the sensor, configure + * the AD714X back to threshold interrupt mode. + */ + ad714x_wheel_use_thr_int(ad714x, idx); + sw->state = IDLE; + input_report_key(sw->input, BTN_TOUCH, 0); + + dev_dbg(ad714x->dev, "wheel %d released\n", + idx); + } + input_sync(sw->input); + } + break; + + default: + break; + } +} + +static void touchpad_cal_sensor_val(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + int i; + + ad714x->read(ad714x, CDC_RESULT_S0 + hw->x_start_stage, + &ad714x->adc_reg[hw->x_start_stage], + hw->x_end_stage - hw->x_start_stage + 1); + + for (i = hw->x_start_stage; i <= hw->x_end_stage; i++) { + ad714x->read(ad714x, STAGE0_AMBIENT + i * PER_STAGE_REG_NUM, + &ad714x->amb_reg[i], 1); + if (ad714x->adc_reg[i] > ad714x->amb_reg[i]) + ad714x->sensor_val[i] = + ad714x->adc_reg[i] - ad714x->amb_reg[i]; + else + ad714x->sensor_val[i] = 0; + } +} + +static void touchpad_cal_highest_stage(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx]; + + sw->x_highest_stage = ad714x_cal_highest_stage(ad714x, + hw->x_start_stage, hw->x_end_stage); + sw->y_highest_stage = ad714x_cal_highest_stage(ad714x, + hw->y_start_stage, hw->y_end_stage); + + dev_dbg(ad714x->dev, + "touchpad %d x_highest_stage:%d, y_highest_stage:%d\n", + idx, sw->x_highest_stage, sw->y_highest_stage); +} + +/* + * If 2 fingers are touching the sensor then 2 peaks can be observed in the + * distribution. + * The arithmetic doesn't support to get absolute coordinates for multi-touch + * yet. + */ +static int touchpad_check_second_peak(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx]; + int i; + + for (i = hw->x_start_stage; i < sw->x_highest_stage; i++) { + if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1]) + > (ad714x->sensor_val[i + 1] / 10)) + return 1; + } + + for (i = sw->x_highest_stage; i < hw->x_end_stage; i++) { + if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i]) + > (ad714x->sensor_val[i] / 10)) + return 1; + } + + for (i = hw->y_start_stage; i < sw->y_highest_stage; i++) { + if ((ad714x->sensor_val[i] - ad714x->sensor_val[i + 1]) + > (ad714x->sensor_val[i + 1] / 10)) + return 1; + } + + for (i = sw->y_highest_stage; i < hw->y_end_stage; i++) { + if ((ad714x->sensor_val[i + 1] - ad714x->sensor_val[i]) + > (ad714x->sensor_val[i] / 10)) + return 1; + } + + return 0; +} + +/* + * If only one finger is used to activate the touch pad then only 1 peak will be + * registered in the distribution. This peak and the 2 adjacent sensors will be + * used in the calculation of the absolute position. This will prevent hand + * shadows to affect the absolute position calculation. + */ +static void touchpad_cal_abs_pos(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx]; + + sw->x_abs_pos = ad714x_cal_abs_pos(ad714x, hw->x_start_stage, + hw->x_end_stage, sw->x_highest_stage, hw->x_max_coord); + sw->y_abs_pos = ad714x_cal_abs_pos(ad714x, hw->y_start_stage, + hw->y_end_stage, sw->y_highest_stage, hw->y_max_coord); + + dev_dbg(ad714x->dev, "touchpad %d absolute position:(%d, %d)\n", idx, + sw->x_abs_pos, sw->y_abs_pos); +} + +static void touchpad_cal_flt_pos(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx]; + + sw->x_flt_pos = (sw->x_flt_pos * (10 - 4) + + sw->x_abs_pos * 4)/10; + sw->y_flt_pos = (sw->y_flt_pos * (10 - 4) + + sw->y_abs_pos * 4)/10; + + dev_dbg(ad714x->dev, "touchpad %d filter position:(%d, %d)\n", + idx, sw->x_flt_pos, sw->y_flt_pos); +} + +/* + * To prevent distortion from showing in the absolute position, it is + * necessary to detect the end points. When endpoints are detected, the + * driver stops updating the status variables with absolute positions. + * End points are detected on the 4 edges of the touchpad sensor. The + * method to detect them is the same for all 4. + * To detect the end points, the firmware computes the difference in + * percent between the sensor on the edge and the adjacent one. The + * difference is calculated in percent in order to make the end point + * detection independent of the pressure. + */ + +#define LEFT_END_POINT_DETECTION_LEVEL 550 +#define RIGHT_END_POINT_DETECTION_LEVEL 750 +#define LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL 850 +#define TOP_END_POINT_DETECTION_LEVEL 550 +#define BOTTOM_END_POINT_DETECTION_LEVEL 950 +#define TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL 700 +static int touchpad_check_endpoint(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx]; + int percent_sensor_diff; + + /* left endpoint detect */ + percent_sensor_diff = (ad714x->sensor_val[hw->x_start_stage] - + ad714x->sensor_val[hw->x_start_stage + 1]) * 100 / + ad714x->sensor_val[hw->x_start_stage + 1]; + if (!sw->left_ep) { + if (percent_sensor_diff >= LEFT_END_POINT_DETECTION_LEVEL) { + sw->left_ep = 1; + sw->left_ep_val = + ad714x->sensor_val[hw->x_start_stage + 1]; + } + } else { + if ((percent_sensor_diff < LEFT_END_POINT_DETECTION_LEVEL) && + (ad714x->sensor_val[hw->x_start_stage + 1] > + LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->left_ep_val)) + sw->left_ep = 0; + } + + /* right endpoint detect */ + percent_sensor_diff = (ad714x->sensor_val[hw->x_end_stage] - + ad714x->sensor_val[hw->x_end_stage - 1]) * 100 / + ad714x->sensor_val[hw->x_end_stage - 1]; + if (!sw->right_ep) { + if (percent_sensor_diff >= RIGHT_END_POINT_DETECTION_LEVEL) { + sw->right_ep = 1; + sw->right_ep_val = + ad714x->sensor_val[hw->x_end_stage - 1]; + } + } else { + if ((percent_sensor_diff < RIGHT_END_POINT_DETECTION_LEVEL) && + (ad714x->sensor_val[hw->x_end_stage - 1] > + LEFT_RIGHT_END_POINT_DEAVTIVALION_LEVEL + sw->right_ep_val)) + sw->right_ep = 0; + } + + /* top endpoint detect */ + percent_sensor_diff = (ad714x->sensor_val[hw->y_start_stage] - + ad714x->sensor_val[hw->y_start_stage + 1]) * 100 / + ad714x->sensor_val[hw->y_start_stage + 1]; + if (!sw->top_ep) { + if (percent_sensor_diff >= TOP_END_POINT_DETECTION_LEVEL) { + sw->top_ep = 1; + sw->top_ep_val = + ad714x->sensor_val[hw->y_start_stage + 1]; + } + } else { + if ((percent_sensor_diff < TOP_END_POINT_DETECTION_LEVEL) && + (ad714x->sensor_val[hw->y_start_stage + 1] > + TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->top_ep_val)) + sw->top_ep = 0; + } + + /* bottom endpoint detect */ + percent_sensor_diff = (ad714x->sensor_val[hw->y_end_stage] - + ad714x->sensor_val[hw->y_end_stage - 1]) * 100 / + ad714x->sensor_val[hw->y_end_stage - 1]; + if (!sw->bottom_ep) { + if (percent_sensor_diff >= BOTTOM_END_POINT_DETECTION_LEVEL) { + sw->bottom_ep = 1; + sw->bottom_ep_val = + ad714x->sensor_val[hw->y_end_stage - 1]; + } + } else { + if ((percent_sensor_diff < BOTTOM_END_POINT_DETECTION_LEVEL) && + (ad714x->sensor_val[hw->y_end_stage - 1] > + TOP_BOTTOM_END_POINT_DEAVTIVALION_LEVEL + sw->bottom_ep_val)) + sw->bottom_ep = 0; + } + + return sw->left_ep || sw->right_ep || sw->top_ep || sw->bottom_ep; +} + +static void touchpad_use_com_int(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + + ad714x_use_com_int(ad714x, hw->x_start_stage, hw->x_end_stage); +} + +static void touchpad_use_thr_int(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + + ad714x_use_thr_int(ad714x, hw->x_start_stage, hw->x_end_stage); + ad714x_use_thr_int(ad714x, hw->y_start_stage, hw->y_end_stage); +} + +static void ad714x_touchpad_state_machine(struct ad714x_chip *ad714x, int idx) +{ + struct ad714x_touchpad_plat *hw = &ad714x->hw->touchpad[idx]; + struct ad714x_touchpad_drv *sw = &ad714x->sw->touchpad[idx]; + unsigned short h_state, c_state; + unsigned short mask; + + mask = (((1 << (hw->x_end_stage + 1)) - 1) - + ((1 << hw->x_start_stage) - 1)) + + (((1 << (hw->y_end_stage + 1)) - 1) - + ((1 << hw->y_start_stage) - 1)); + + h_state = ad714x->h_state & mask; + c_state = ad714x->c_state & mask; + + switch (sw->state) { + case IDLE: + if (h_state) { + sw->state = JITTER; + /* In End of Conversion interrupt mode, the AD714X + * continuously generates hardware interrupts. + */ + touchpad_use_com_int(ad714x, idx); + dev_dbg(ad714x->dev, "touchpad %d touched\n", idx); + } + break; + + case JITTER: + if (c_state == mask) { + touchpad_cal_sensor_val(ad714x, idx); + touchpad_cal_highest_stage(ad714x, idx); + if ((!touchpad_check_second_peak(ad714x, idx)) && + (!touchpad_check_endpoint(ad714x, idx))) { + dev_dbg(ad714x->dev, + "touchpad%d, 2 fingers or endpoint\n", + idx); + touchpad_cal_abs_pos(ad714x, idx); + sw->x_flt_pos = sw->x_abs_pos; + sw->y_flt_pos = sw->y_abs_pos; + sw->state = ACTIVE; + } + } + break; + + case ACTIVE: + if (c_state == mask) { + if (h_state) { + touchpad_cal_sensor_val(ad714x, idx); + touchpad_cal_highest_stage(ad714x, idx); + if ((!touchpad_check_second_peak(ad714x, idx)) + && (!touchpad_check_endpoint(ad714x, idx))) { + touchpad_cal_abs_pos(ad714x, idx); + touchpad_cal_flt_pos(ad714x, idx); + input_report_abs(sw->input, ABS_X, + sw->x_flt_pos); + input_report_abs(sw->input, ABS_Y, + sw->y_flt_pos); + input_report_key(sw->input, BTN_TOUCH, + 1); + } + } else { + /* When the user lifts off the sensor, configure + * the AD714X back to threshold interrupt mode. + */ + touchpad_use_thr_int(ad714x, idx); + sw->state = IDLE; + input_report_key(sw->input, BTN_TOUCH, 0); + dev_dbg(ad714x->dev, "touchpad %d released\n", + idx); + } + input_sync(sw->input); + } + break; + + default: + break; + } +} + +static int ad714x_hw_detect(struct ad714x_chip *ad714x) +{ + unsigned short data; + + ad714x->read(ad714x, AD714X_PARTID_REG, &data, 1); + switch (data & 0xFFF0) { + case AD7142_PARTID: + ad714x->product = 0x7142; + ad714x->version = data & 0xF; + dev_info(ad714x->dev, "found AD7142 captouch, rev:%d\n", + ad714x->version); + return 0; + + case AD7143_PARTID: + ad714x->product = 0x7143; + ad714x->version = data & 0xF; + dev_info(ad714x->dev, "found AD7143 captouch, rev:%d\n", + ad714x->version); + return 0; + + case AD7147_PARTID: + ad714x->product = 0x7147; + ad714x->version = data & 0xF; + dev_info(ad714x->dev, "found AD7147(A) captouch, rev:%d\n", + ad714x->version); + return 0; + + case AD7148_PARTID: + ad714x->product = 0x7148; + ad714x->version = data & 0xF; + dev_info(ad714x->dev, "found AD7148 captouch, rev:%d\n", + ad714x->version); + return 0; + + default: + dev_err(ad714x->dev, + "fail to detect AD714X captouch, read ID is %04x\n", + data); + return -ENODEV; + } +} + +static void ad714x_hw_init(struct ad714x_chip *ad714x) +{ + int i, j; + unsigned short reg_base; + unsigned short data; + + /* configuration CDC and interrupts */ + + for (i = 0; i < STAGE_NUM; i++) { + reg_base = AD714X_STAGECFG_REG + i * STAGE_CFGREG_NUM; + for (j = 0; j < STAGE_CFGREG_NUM; j++) + ad714x->write(ad714x, reg_base + j, + ad714x->hw->stage_cfg_reg[i][j]); + } + + for (i = 0; i < SYS_CFGREG_NUM; i++) + ad714x->write(ad714x, AD714X_SYSCFG_REG + i, + ad714x->hw->sys_cfg_reg[i]); + for (i = 0; i < SYS_CFGREG_NUM; i++) + ad714x->read(ad714x, AD714X_SYSCFG_REG + i, &data, 1); + + ad714x->write(ad714x, AD714X_STG_CAL_EN_REG, 0xFFF); + + /* clear all interrupts */ + ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3); +} + +static irqreturn_t ad714x_interrupt_thread(int irq, void *data) +{ + struct ad714x_chip *ad714x = data; + int i; + + mutex_lock(&ad714x->mutex); + + ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3); + + for (i = 0; i < ad714x->hw->button_num; i++) + ad714x_button_state_machine(ad714x, i); + for (i = 0; i < ad714x->hw->slider_num; i++) + ad714x_slider_state_machine(ad714x, i); + for (i = 0; i < ad714x->hw->wheel_num; i++) + ad714x_wheel_state_machine(ad714x, i); + for (i = 0; i < ad714x->hw->touchpad_num; i++) + ad714x_touchpad_state_machine(ad714x, i); + + mutex_unlock(&ad714x->mutex); + + return IRQ_HANDLED; +} + +struct ad714x_chip *ad714x_probe(struct device *dev, u16 bus_type, int irq, + ad714x_read_t read, ad714x_write_t write) +{ + int i; + int error; + struct input_dev *input; + + struct ad714x_platform_data *plat_data = dev_get_platdata(dev); + struct ad714x_chip *ad714x; + void *drv_mem; + unsigned long irqflags; + + struct ad714x_button_drv *bt_drv; + struct ad714x_slider_drv *sd_drv; + struct ad714x_wheel_drv *wl_drv; + struct ad714x_touchpad_drv *tp_drv; + + + if (irq <= 0) { + dev_err(dev, "IRQ not configured!\n"); + error = -EINVAL; + return ERR_PTR(error); + } + + if (dev_get_platdata(dev) == NULL) { + dev_err(dev, "platform data for ad714x doesn't exist\n"); + error = -EINVAL; + return ERR_PTR(error); + } + + ad714x = devm_kzalloc(dev, sizeof(*ad714x) + sizeof(*ad714x->sw) + + sizeof(*sd_drv) * plat_data->slider_num + + sizeof(*wl_drv) * plat_data->wheel_num + + sizeof(*tp_drv) * plat_data->touchpad_num + + sizeof(*bt_drv) * plat_data->button_num, + GFP_KERNEL); + if (!ad714x) { + error = -ENOMEM; + return ERR_PTR(error); + } + ad714x->hw = plat_data; + + drv_mem = ad714x + 1; + ad714x->sw = drv_mem; + drv_mem += sizeof(*ad714x->sw); + ad714x->sw->slider = sd_drv = drv_mem; + drv_mem += sizeof(*sd_drv) * ad714x->hw->slider_num; + ad714x->sw->wheel = wl_drv = drv_mem; + drv_mem += sizeof(*wl_drv) * ad714x->hw->wheel_num; + ad714x->sw->touchpad = tp_drv = drv_mem; + drv_mem += sizeof(*tp_drv) * ad714x->hw->touchpad_num; + ad714x->sw->button = bt_drv = drv_mem; + drv_mem += sizeof(*bt_drv) * ad714x->hw->button_num; + + ad714x->read = read; + ad714x->write = write; + ad714x->irq = irq; + ad714x->dev = dev; + + error = ad714x_hw_detect(ad714x); + if (error) + return ERR_PTR(error); + + /* initialize and request sw/hw resources */ + + ad714x_hw_init(ad714x); + mutex_init(&ad714x->mutex); + + /* a slider uses one input_dev instance */ + if (ad714x->hw->slider_num > 0) { + struct ad714x_slider_plat *sd_plat = ad714x->hw->slider; + + for (i = 0; i < ad714x->hw->slider_num; i++) { + input = devm_input_allocate_device(dev); + if (!input) + return ERR_PTR(-ENOMEM); + + __set_bit(EV_ABS, input->evbit); + __set_bit(EV_KEY, input->evbit); + __set_bit(ABS_X, input->absbit); + __set_bit(BTN_TOUCH, input->keybit); + input_set_abs_params(input, + ABS_X, 0, sd_plat->max_coord, 0, 0); + + input->id.bustype = bus_type; + input->id.product = ad714x->product; + input->id.version = ad714x->version; + input->name = "ad714x_captouch_slider"; + input->dev.parent = dev; + + error = input_register_device(input); + if (error) + return ERR_PTR(error); + + sd_drv[i].input = input; + } + } + + /* a wheel uses one input_dev instance */ + if (ad714x->hw->wheel_num > 0) { + struct ad714x_wheel_plat *wl_plat = ad714x->hw->wheel; + + for (i = 0; i < ad714x->hw->wheel_num; i++) { + input = devm_input_allocate_device(dev); + if (!input) + return ERR_PTR(-ENOMEM); + + __set_bit(EV_KEY, input->evbit); + __set_bit(EV_ABS, input->evbit); + __set_bit(ABS_WHEEL, input->absbit); + __set_bit(BTN_TOUCH, input->keybit); + input_set_abs_params(input, + ABS_WHEEL, 0, wl_plat->max_coord, 0, 0); + + input->id.bustype = bus_type; + input->id.product = ad714x->product; + input->id.version = ad714x->version; + input->name = "ad714x_captouch_wheel"; + input->dev.parent = dev; + + error = input_register_device(input); + if (error) + return ERR_PTR(error); + + wl_drv[i].input = input; + } + } + + /* a touchpad uses one input_dev instance */ + if (ad714x->hw->touchpad_num > 0) { + struct ad714x_touchpad_plat *tp_plat = ad714x->hw->touchpad; + + for (i = 0; i < ad714x->hw->touchpad_num; i++) { + input = devm_input_allocate_device(dev); + if (!input) + return ERR_PTR(-ENOMEM); + + __set_bit(EV_ABS, input->evbit); + __set_bit(EV_KEY, input->evbit); + __set_bit(ABS_X, input->absbit); + __set_bit(ABS_Y, input->absbit); + __set_bit(BTN_TOUCH, input->keybit); + input_set_abs_params(input, + ABS_X, 0, tp_plat->x_max_coord, 0, 0); + input_set_abs_params(input, + ABS_Y, 0, tp_plat->y_max_coord, 0, 0); + + input->id.bustype = bus_type; + input->id.product = ad714x->product; + input->id.version = ad714x->version; + input->name = "ad714x_captouch_pad"; + input->dev.parent = dev; + + error = input_register_device(input); + if (error) + return ERR_PTR(error); + + tp_drv[i].input = input; + } + } + + /* all buttons use one input node */ + if (ad714x->hw->button_num > 0) { + struct ad714x_button_plat *bt_plat = ad714x->hw->button; + + input = devm_input_allocate_device(dev); + if (!input) { + error = -ENOMEM; + return ERR_PTR(error); + } + + __set_bit(EV_KEY, input->evbit); + for (i = 0; i < ad714x->hw->button_num; i++) { + bt_drv[i].input = input; + __set_bit(bt_plat[i].keycode, input->keybit); + } + + input->id.bustype = bus_type; + input->id.product = ad714x->product; + input->id.version = ad714x->version; + input->name = "ad714x_captouch_button"; + input->dev.parent = dev; + + error = input_register_device(input); + if (error) + return ERR_PTR(error); + } + + irqflags = plat_data->irqflags ?: IRQF_TRIGGER_FALLING; + irqflags |= IRQF_ONESHOT; + + error = devm_request_threaded_irq(dev, ad714x->irq, NULL, + ad714x_interrupt_thread, + irqflags, "ad714x_captouch", ad714x); + if (error) { + dev_err(dev, "can't allocate irq %d\n", ad714x->irq); + return ERR_PTR(error); + } + + return ad714x; +} +EXPORT_SYMBOL(ad714x_probe); + +#ifdef CONFIG_PM +int ad714x_disable(struct ad714x_chip *ad714x) +{ + unsigned short data; + + dev_dbg(ad714x->dev, "%s enter\n", __func__); + + mutex_lock(&ad714x->mutex); + + data = ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL] | 0x3; + ad714x->write(ad714x, AD714X_PWR_CTRL, data); + + mutex_unlock(&ad714x->mutex); + + return 0; +} +EXPORT_SYMBOL(ad714x_disable); + +int ad714x_enable(struct ad714x_chip *ad714x) +{ + dev_dbg(ad714x->dev, "%s enter\n", __func__); + + mutex_lock(&ad714x->mutex); + + /* resume to non-shutdown mode */ + + ad714x->write(ad714x, AD714X_PWR_CTRL, + ad714x->hw->sys_cfg_reg[AD714X_PWR_CTRL]); + + /* make sure the interrupt output line is not low level after resume, + * otherwise we will get no chance to enter falling-edge irq again + */ + + ad714x->read(ad714x, STG_LOW_INT_STA_REG, &ad714x->l_state, 3); + + mutex_unlock(&ad714x->mutex); + + return 0; +} +EXPORT_SYMBOL(ad714x_enable); +#endif + +MODULE_DESCRIPTION("Analog Devices AD714X Capacitance Touch Sensor Driver"); +MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>"); +MODULE_LICENSE("GPL"); |