From deb61e0622f58b58b6f61d1822054df04cf09456 Mon Sep 17 00:00:00 2001 From: Amaury Pouly Date: Sat, 19 May 2012 13:47:12 +0200 Subject: Add the MPR121 (touchbutton chip) driver Change-Id: I9db97a698ef1c7f0b4f47e406faa1f6c0ec524db --- firmware/drivers/mpr121.c | 350 ++++++++++++++++++++++++++++++++++++++++++++++ firmware/export/mpr121.h | 170 ++++++++++++++++++++++ 2 files changed, 520 insertions(+) create mode 100644 firmware/drivers/mpr121.c create mode 100644 firmware/export/mpr121.h diff --git a/firmware/drivers/mpr121.c b/firmware/drivers/mpr121.c new file mode 100644 index 0000000000..7b41208a3a --- /dev/null +++ b/firmware/drivers/mpr121.c @@ -0,0 +1,350 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * + * Copyright (C) 2012 Amaury Pouly + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ****************************************************************************/ + +/** Driver for the Freescale MPR121 Capacitive Proximity Sensor */ +#include "system.h" +#include "mpr121.h" +#include "i2c.h" + +/* Touch status: EL{0,7} */ +#define REG_TOUCH_STATUS 0x00 +#define REG_TOUCH_STATUS__ELE(x) (1 << (x)) +/* Touch status: EL{8-11,prox}, overcurrent */ +#define REG_TOUCH_STATUS2 0x01 +#define REG_TOUCH_STATUS2__ELE(x) (1 << ((x) - 8)) +#define REG_TOUCH_STATUS2__ELEPROX (1 << 4) +#define REG_TOUCH_STATUS2__OVCF (1 << 7) +/* Out of range: EL{0,7} */ +#define REG_OOR_STATUS 0x02 +#define REG_OOR_STATUS__ELE(x) (1 << (x)) +/* Out of range: EL{8-11,prox}, autoconf err */ +#define REG_OOR_STATUS2 0x03 +#define REG_OOR_STATUS2__ELE(x) (1 << (x)) +#define REG_OOR_STATUS2__ELEPROX (1 << 4) +#define REG_OOR_STATUS2__ACFF (1 << 6) +#define REG_OOR_STATUS2__ARFF (1 << 7) +/* Electrode X filtered data LSB */ +#define REG_EFDxLB(x) (0x04 + 0x02 * (x)) +/* Electrode X filtered data MSB */ +#define REG_EFDxHB(x) (0x05 + 0x02 * (x)) +/* Proximity electrode X filtered data LSB */ +#define REG_EFDPROXLB 0x1c +/* Proximity electrode X filtered data MSB */ +#define REG_EFDPROXHB 0x1d +/* Electrode baseline value */ +#define REG_ExBV(x) (0x1e + (x)) +/* Proximity electrode baseline value */ +#define REG_EPROXBV 0x2a +/* Max Half Delta Rising */ +#define REG_MHDR 0x2b +/* Noise Half Delta Rising */ +#define REG_NHDR 0x2c +/* Noise Count Limit Rising */ +#define REG_NCLR 0x2d +/* Filter Delay Limit Rising */ +#define REG_FDLR 0x2e +/* Max Half Delta Falling */ +#define REG_MHDF 0x2f +/* Noise Half Delta Falling */ +#define REG_NHDF 0x30 +/* Noise Count Limit Falling */ +#define REG_NCLF 0x31 +/* Filter Delay Limit Falling */ +#define REG_FDLF 0x32 +/* Noise Half Delta Touched */ +#define REG_NHDT 0x33 +/* Noise Count Limit Touched */ +#define REG_NCLT 0x34 +/* Filter Delay Limit Touched */ +#define REG_FDLT 0x35 +/* Proximity Max Half Delta Rising */ +#define REG_MHDPROXR 0x36 +/* Proximity Noise Half Delta Rising */ +#define REG_NHDPROXR 0x37 +/* Proximity Noise Count Limit Rising */ +#define REG_NCLPROXR 0x38 +/* Proximity Filter Delay Limit Rising */ +#define REG_FDLPROXR 0x39 +/* Proximity Max Half Delta Falling */ +#define REG_MHDPROXF 0x3a +/* Proximity Noise Half Delta Falling */ +#define REG_NHDPROXF 0x3b +/* Proximity Noise Count Limit Falling */ +#define REG_NCLPROXF 0x3c +/* Proximity Filter Delay Limit Falling */ +#define REG_FDLPROXF 0x3d +/* Proximity Noise Half Delta Touched */ +#define REG_NHDPROXT 0x3e +/* Proximity Noise Count Limit Touched */ +#define REG_NCLPROXT 0x3f +/* Proximity Filter Delay Limit Touched */ +#define REG_FDLPROXT 0x40 +/* Eletrode Touch Threshold */ +#define REG_ExTTH(x) (0x41 + 2 * (x)) +/* Eletrode Release Threshold */ +#define REG_ExRTH(x) (0x42 + 2 * (x)) +/* Proximity Eletrode Touch Threshold */ +#define REG_EPROXTTH 0x59 +/* Proximity Eletrode Release Threshold */ +#define REG_EPROXRTH 0x5a +/* Debounce Control */ +#define REG_DEBOUNCE 0x5b +#define REG_DEBOUNCE__DR(dr) ((dr) << 4) +#define REG_DEBOUNCE__DT(dt) (dt) +/* Analog Front End Configuration */ +#define REG_AFE 0x5c +#define REG_AFE__CDC(cdc) (cdc) +#define REG_AFE__FFI(ffi) ((ffi) << 6) +/* Filter Configuration */ +#define REG_FILTER 0x5d +#define REG_FILTER__ESI(esi) (esi) +#define REG_FILTER__SFI(sfi) ((sfi) << 3) +#define REG_FILTER__CDT(cdt) ((cdt) << 5) +/* Electrode Configuration */ +#define REG_ELECTRODE 0x5e +#define REG_ELECTRODE__ELE_EN(en) (en) +#define REG_ELECTRODE__ELEPROX_EN(en) ((en) << 4) +#define REG_ELECTRODE__CL(cl) ((cl) << 6) +/* Electrode X Current */ +#define REG_CDCx(x) (0x5f + (x)) +/* Proximity Eletrode X Current */ +#define REG_CDCPROX 0x6b +/* Electrode X Charge Time */ +#define REG_CDTx(x) (0x6c + (x) / 2) +#define REG_CDTx__CDT0(x) (x) +#define REG_CDTx__CDT1(x) ((x) << 4) +/* Proximity Eletrode X Charge Time */ +#define REG_CDTPROX 0x72 +/* GPIO Control Register: CTL0{4-11} */ +#define REG_GPIO_CTL0 0x73 +#define REG_GPIO_CTL0__CTL0x(x) (1 << ((x) - 4)) +/* GPIO Control Register: CTL1{4-11} */ +#define REG_GPIO_CTL1 0x74 +#define REG_GPIO_CTL1__CTL1x(x) (1 << ((x) - 4)) +/* GPIO Data Register */ +#define REG_GPIO_DATA 0x75 +#define REG_GPIO_DATA__DATx(x) (1 << ((x) - 4)) +/* GPIO Direction Register */ +#define REG_GPIO_DIR 0x76 +#define REG_GPIO_DIR__DIRx(x) (1 << ((x) - 4)) +/* GPIO Enable Register */ +#define REG_GPIO_EN 0x77 +#define REG_GPIO_EN__ENx(x) (1 << ((x) - 4)) +/* GPIO Data Set Register */ +#define REG_GPIO_SET 0x78 +#define REG_GPIO_SET__SETx(x) (1 << ((x) - 4)) +/* GPIO Data Clear Register */ +#define REG_GPIO_CLR 0x79 +#define REG_GPIO_CLR__CLRx(x) (1 << ((x) - 4)) +/* GPIO Data Toggle Register */ +#define REG_GPIO_TOG 0x7a +#define REG_GPIO_TOG__TOGx(x) (1 << ((x) - 4)) +/* Auto-Configuration Control 0 */ +#define REG_AUTO_CONF 0x7b +#define REG_AUTO_CONF__ACE(ace) (ace) +#define REG_AUTO_CONF__ARE(are) ((are) << 1) +#define REG_AUTO_CONF__BVA(bva) ((bva) << 2) +#define REG_AUTO_CONF__RETRY(retry) ((retry) << 4) +#define REG_AUTO_CONF__FFI(ffi) ((ffi) << 6) +/* Auto-Configuration Control 1 */ +#define REG_AUTO_CONF2 0x7c +#define REG_AUTO_CONF2__ACFIE(acfie) (acfie) +#define REG_AUTO_CONF2__ARFIE(arfie) ((arfie) << 1) +#define REG_AUTO_CONF2__OORIE(oorie) ((oorie) << 2) +#define REG_AUTO_CONF2__SCTS(scts) ((scts) << 7) +/* Auto-Configuration Upper-Limit */ +#define REG_USL 0x7d +/* Auto-Configuration Lower-Limit */ +#define REG_LSL 0x7e +/* Auto-Configuration Target Level */ +#define REG_TL 0x7f +/* Soft-Reset */ +#define REG_SOFTRESET 0x80 +#define REG_SOFTRESET__MAGIC 0x63 +/* PWM Control */ +#define REG_PWMx(x) (0x81 + ((x) - 4) / 2) +#define REG_PWMx_IS_PWM0(x) (((x) % 2) == 0) +#define REG_PWMx__PWM0(x) (x) +#define REG_PWMx__PWM0_BM 0xf +#define REG_PWMx__PWM1(x) ((x) << 4) +#define REG_PWMx__PWM1_BM 0xf0 + +static int i2c_addr; + +static inline int mpr121_write_reg(uint8_t reg, uint8_t data) +{ + return i2c_writemem(i2c_addr, reg, &data, 1); +} + +static inline int mpr121_read_reg(uint8_t reg, uint8_t *data) +{ + return i2c_readmem(i2c_addr, reg, data, 1); +} + +int mpr121_init(int dev_i2c_addr) +{ + i2c_addr = dev_i2c_addr; + return 0; +} + +int mpr121_soft_reset(void) +{ + return mpr121_write_reg(REG_SOFTRESET, REG_SOFTRESET__MAGIC); +} +int mpr121_set_config(struct mpr121_config_t *conf) +{ + int ret; +#define safe_write(reg, val) \ + do { ret = mpr121_write_reg(reg, val); \ + if(ret) return ret; } while(0) + /* stop mode */ + safe_write(REG_ELECTRODE, 0); + /* write baseline values */ + for(int i = 0; i < ELECTRODE_COUNT; i++) + safe_write(REG_ExBV(i), conf->ele[i].bv); + /* write eleprox bv */ + safe_write(REG_EPROXBV, conf->eleprox.bv); + /* write global fields */ + safe_write(REG_MHDR, conf->filters.ele.rising.mhd); + safe_write(REG_NHDR, conf->filters.ele.rising.nhd); + safe_write(REG_NCLR, conf->filters.ele.rising.ncl); + safe_write(REG_FDLR, conf->filters.ele.rising.fdl); + safe_write(REG_MHDF, conf->filters.ele.falling.mhd); + safe_write(REG_NHDF, conf->filters.ele.falling.nhd); + safe_write(REG_NCLF, conf->filters.ele.falling.ncl); + safe_write(REG_FDLF, conf->filters.ele.falling.fdl); + safe_write(REG_NHDT, conf->filters.ele.touched.nhd); + safe_write(REG_NCLT, conf->filters.ele.touched.ncl); + safe_write(REG_FDLT, conf->filters.ele.touched.fdl); + safe_write(REG_MHDPROXR, conf->filters.eleprox.rising.mhd); + safe_write(REG_NHDPROXR, conf->filters.eleprox.rising.nhd); + safe_write(REG_NCLPROXR, conf->filters.eleprox.rising.ncl); + safe_write(REG_FDLPROXR, conf->filters.eleprox.rising.fdl); + safe_write(REG_MHDPROXF, conf->filters.eleprox.falling.mhd); + safe_write(REG_NHDPROXF, conf->filters.eleprox.falling.nhd); + safe_write(REG_NCLPROXF, conf->filters.eleprox.falling.ncl); + safe_write(REG_FDLPROXF, conf->filters.eleprox.falling.fdl); + safe_write(REG_NHDPROXT, conf->filters.eleprox.touched.nhd); + safe_write(REG_NCLPROXT, conf->filters.eleprox.touched.ncl); + safe_write(REG_FDLPROXT, conf->filters.eleprox.touched.fdl); + /* touch & release thresholds */ + for(int i = 0; i < ELECTRODE_COUNT; i++) + { + safe_write(REG_ExTTH(i), conf->ele[i].tth); + safe_write(REG_ExRTH(i), conf->ele[i].rth); + } + safe_write(REG_EPROXTTH, conf->eleprox.tth); + safe_write(REG_EPROXRTH, conf->eleprox.rth); + /* debounce */ + safe_write(REG_DEBOUNCE, REG_DEBOUNCE__DR(conf->debounce.dr) | + REG_DEBOUNCE__DT(conf->debounce.dt)); + /* analog-front end and filters */ + safe_write(REG_AFE, REG_AFE__CDC(conf->global.cdc) | + REG_AFE__FFI(conf->global.ffi)); + safe_write(REG_FILTER, REG_FILTER__CDT(conf->global.cdt) | + REG_FILTER__ESI(conf->global.esi) | REG_FILTER__SFI(conf->global.sfi)); + /* electrode charge */ + for(int i = 0; i < ELECTRODE_COUNT; i++) + safe_write(REG_CDCx(i), conf->ele[i].cdc); + safe_write(REG_CDCPROX, conf->eleprox.cdc); + for(int i = 0; i < ELECTRODE_COUNT; i += 2) + { + safe_write(REG_CDTx(i), REG_CDTx__CDT0(conf->ele[i].cdt) | + REG_CDTx__CDT1(conf->ele[i+1].cdt)); + } + safe_write(REG_CDTPROX, conf->eleprox.cdt); + /* Auto-Configuration */ + safe_write(REG_AUTO_CONF, REG_AUTO_CONF__ACE(conf->autoconf.en) | + REG_AUTO_CONF__ARE(conf->autoconf.ren) | + REG_AUTO_CONF__BVA(conf->cal_lock) | + REG_AUTO_CONF__RETRY(conf->autoconf.retry) | + REG_AUTO_CONF__FFI(conf->global.ffi)); + safe_write(REG_AUTO_CONF2, REG_AUTO_CONF2__ACFIE(conf->autoconf.acfie) | + REG_AUTO_CONF2__ARFIE(conf->autoconf.arfie) | + REG_AUTO_CONF2__OORIE(conf->autoconf.oorie) | + REG_AUTO_CONF2__SCTS(conf->autoconf.scts)); + safe_write(REG_USL, conf->autoconf.usl); + safe_write(REG_LSL, conf->autoconf.lsl); + safe_write(REG_TL, conf->autoconf.tl); + /* electrode configuration */ + safe_write(REG_ELECTRODE, REG_ELECTRODE__ELE_EN(conf->ele_en) | + REG_ELECTRODE__ELEPROX_EN(conf->eleprox_en) | + REG_ELECTRODE__CL(conf->cal_lock)); + /* gpio config */ + uint8_t ctl = 0; + for(int i = ELE_GPIO_FIRST; i <= ELE_GPIO_LAST; i++) + if(ELE_GPIO_CTL0(conf->ele[i].gpio)) + ctl |= REG_GPIO_CTL0__CTL0x(i); + safe_write(REG_GPIO_CTL0, ctl); + ctl = 0; + for(int i = ELE_GPIO_FIRST; i <= ELE_GPIO_LAST; i++) + if(ELE_GPIO_CTL1(conf->ele[i].gpio)) + ctl |= REG_GPIO_CTL1__CTL1x(i); + safe_write(REG_GPIO_CTL1, ctl); + ctl = 0; + for(int i = ELE_GPIO_FIRST; i <= ELE_GPIO_LAST; i++) + if(ELE_GPIO_DIR(conf->ele[i].gpio)) + ctl |= REG_GPIO_DIR__DIRx(i); + safe_write(REG_GPIO_DIR, ctl); + ctl = 0; + for(int i = ELE_GPIO_FIRST; i <= ELE_GPIO_LAST; i++) + if(ELE_GPIO_EN(conf->ele[i].gpio)) + ctl |= REG_GPIO_EN__ENx(i); + safe_write(REG_GPIO_EN, ctl); + + return 0; +} + +int mpr121_set_gpio_output(int ele, int gpio_val) +{ + switch(gpio_val) + { + case ELE_GPIO_SET: + return mpr121_write_reg(REG_GPIO_SET, REG_GPIO_SET__SETx(ele)); + case ELE_GPIO_CLR: + return mpr121_write_reg(REG_GPIO_CLR, REG_GPIO_CLR__CLRx(ele)); + case ELE_GPIO_TOG: + return mpr121_write_reg(REG_GPIO_TOG, REG_GPIO_TOG__TOGx(ele)); + default: + return -1; + } +} + +int mpr121_set_gpio_pwm(int ele, int pwm) +{ + uint8_t reg_val; + int ret = mpr121_read_reg(REG_PWMx(ele), ®_val); + if(ret) return ret; + if(REG_PWMx_IS_PWM0(ele)) + reg_val = (reg_val & ~REG_PWMx__PWM0_BM) | REG_PWMx__PWM0(pwm); + else + reg_val = (reg_val & ~REG_PWMx__PWM1_BM) | REG_PWMx__PWM1(pwm); + return mpr121_write_reg(REG_PWMx(ele), reg_val); +} + +int mpr121_get_touch_status(unsigned *status) +{ + uint8_t buf[2]; + int ret = i2c_readmem(i2c_addr, REG_TOUCH_STATUS, buf, 2); + if(!ret && status) + *status = buf[0] | buf[1]; + return ret; +} diff --git a/firmware/export/mpr121.h b/firmware/export/mpr121.h new file mode 100644 index 0000000000..96b83ecc90 --- /dev/null +++ b/firmware/export/mpr121.h @@ -0,0 +1,170 @@ +/*************************************************************************** + * __________ __ ___. + * Open \______ \ ____ ____ | | _\_ |__ _______ ___ + * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / + * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < + * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ + * \/ \/ \/ \/ \/ + * $Id$ + * + * Copyright (C) 2012 Amaury Pouly + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ****************************************************************************/ + +/** Driver for the Freescale MPR121 Capacitive Proximity Sensor */ +#include "system.h" + +#define ELECTRODE_COUNT 12 +#define ELE_GPIO_FIRST 4 +#define ELE_GPIO_LAST 11 + +/* gpio config (encoding: [0]=en,[1]=dir,[2]=ctl[1],[3]=ctl[0]) */ +#define ELE_GPIO_DISABLE 0 +#define ELE_GPIO_INPUT 1 +#define ELE_GPIO_INPUT_PULLDOWN 9 /* input with pull-down */ +#define ELE_GPIO_INPUT_PULLUP 13 /* input with pull-up */ +#define ELE_GPIO_OUTPUT 3 +#define ELE_GPIO_OUTPUT_OPEN 11 /* open drain low-side */ +#define ELE_GPIO_OUTPUT_OPEN_LED 15 /* open drain high-side (led driver) */ + +/* internal use */ +#define ELE_GPIO_EN(val) ((val) & 1) +#define ELE_GPIO_DIR(val) (((val) >> 1) & 1) +#define ELE_GPIO_CTL0(val) (((val) >> 3) & 1) +#define ELE_GPIO_CTL1(val) (((val) >> 1) & 1) + +struct mpr121_electrode_config_t +{ + uint8_t bv; /* baseline value */ + uint8_t tth; /* touch threshold */ + uint8_t rth; /* release threshold */ + uint8_t cdc; /* charge current (optional if auto-conf) */ + uint8_t cdt; /* charge time (optional if auto-conf) */ + int gpio; /* gpio config */ +}; + +struct mpr121_baseline_filter_config_t +{ + uint8_t mhd; /* max half delta (except for touched) */ + uint8_t nhd; /* noise half delta */ + uint8_t ncl; /* noise count limit */ + uint8_t fdl; /* filter delay count limit */ +}; + +struct mpr121_baseline_filters_config_t +{ + struct mpr121_baseline_filter_config_t rising; + struct mpr121_baseline_filter_config_t falling; + struct mpr121_baseline_filter_config_t touched; +}; + +struct mpr121_debounce_config_t +{ + uint8_t dt; /* debounce count for touch */ + uint8_t dr; /* debounce count for release */ +}; + +/* first filter iterations */ +#define FFI_6_SAMPLES 0 +#define FFI_10_SAMPLES 1 +#define FFI_18_SAMPLES 2 +#define FFI_34_SAMPLES 3 +/* charge discharge current */ +#define CDC_DISABLE 0 +#define CDC_uA(ua) (ua) +/* charge discharge time */ +#define CDT_DISABLE 0 +#define CDT_log_us(lus) (lus) /* actual value = 2^{us-2} µs */ +/* second filter iterations */ +#define SFI_4_SAMPLES 0 +#define SFI_6_SAMPLES 1 +#define SFI_10_SAMPLES 2 +#define SFI_18_SAMPLES 3 +/* Eletrode sample interval */ +#define ESI_log_ms(lms) (lms) /* actual value = 2^{lms} ms */ + +struct mpr121_global_config_t +{ + uint8_t ffi; /* first filter iterations */ + uint8_t cdc; /* global charge discharge current */ + uint8_t cdt; /* global charge discharge time */ + uint8_t sfi; /* second first iterations */ + uint8_t esi; /* electrode sample interval */ +}; + +#define RETRY_NEVER 0 +#define RETRY_2_TIMES 1 +#define RETRY_4_TIMES 2 +#define RETRY_8_TIMES 3 + +struct mpr121_auto_config_t +{ + bool en; /* auto-conf enable */ + bool ren; /* auto-reconf enable */ + uint8_t retry; /* retry count */ + bool scts; /* skip charge time search */ + uint8_t usl; /* upper-side limit */ + uint8_t lsl; /* lower-side limit */ + uint8_t tl; /* target level */ + bool acfie; /* auto-conf fail interrupt en */ + bool arfie; /* auto-reconf fail interrupt en */ + bool oorie; /* out of range interrupt en */ +}; + +/* electrode mode */ +#define ELE_DISABLE 0 +#define ELE_EN0_x(x) ((x) + 1) +/* eleprox mode */ +#define ELEPROX_DISABLE 0 +#define ELEPROX_EN0_1 1 +#define ELEPROX_EN0_3 2 +#define ELEPROX_EN0_11 3 +/* calibration lock */ +#define CL_SLOW_TRACK 0 +#define CL_DISABLE 1 +#define CL_TRACK 2 +#define CL_FAST_TRACK 3 + +struct mpr121_config_t +{ + struct mpr121_electrode_config_t ele[ELECTRODE_COUNT]; + struct mpr121_electrode_config_t eleprox; + struct + { + struct mpr121_baseline_filters_config_t ele; + struct mpr121_baseline_filters_config_t eleprox; + }filters; + struct mpr121_debounce_config_t debounce; + struct mpr121_global_config_t global; + struct mpr121_auto_config_t autoconf; + uint8_t ele_en; /* eletroce mode */ + uint8_t eleprox_en; /* proximity mode */ + uint8_t cal_lock; /* calibration lock */ +}; + +/* gpio value */ +#define ELE_GPIO_CLR 0 +#define ELE_GPIO_SET 1 +#define ELE_GPIO_TOG 2 +/* pwm value */ +#define ELE_PWM_DISABLE 0 +#define ELE_PWM_DUTY(x) (x) +#define ELE_PWM_MIN_DUTY 1 +#define ELE_PWM_MAX_DUTY 15 + +int mpr121_init(int dev_i2c_addr); +int mpr121_soft_reset(void); +int mpr121_set_config(struct mpr121_config_t *conf); +/* gpios are only implemented for electrode>=4 */ +int mpr121_set_gpio_output(int ele, int gpio_val); +int mpr121_set_gpio_pwm(int ele, int pwm); +/* get electrode status (bitmap) */ +int mpr121_get_touch_status(unsigned *status); -- cgit v1.2.3