From 781375f1d112876e8c867cb45ba30c936d3d760e Mon Sep 17 00:00:00 2001 From: Ricardo de Almeida Gonzaga Date: Thu, 8 Oct 2015 14:16:11 -0300 Subject: [PATCH] x86: Add PCA9685 support This patch adds pwm-pca9685.c and pwm-pca9685.h files, which support access to I2C-based PCA9685 PWM controller configuration register through a function interface. The PCA9685 is an I2C-bus controlled 16-channel LED controller optimized for Red/Green/Blue/Amber (RGBA) color backlighting applications. Each LED output has its own 12-bit resolution (4096 steps) fixed frequency individual PWM controller that operates at a programmable frequency from a typical of 24 Hz to 1526 Hz with a duty cycle that is adjustable from 0 % to 100 % to allow the LED to be set to a specific brightness value. More about PCA9685 can be found in its datasheet[1]. This driver is needed in order to configure Galileo pinmux. [1] - http://www.nxp.com/documents/data_sheet/PCA9685.pdf --- platform/galileo/Makefile.galileo | 2 +- platform/galileo/drivers/pwm-pca9685.c | 118 +++++++++++++++++++++++++ platform/galileo/drivers/pwm-pca9685.h | 44 +++++++++ 3 files changed, 163 insertions(+), 1 deletion(-) create mode 100644 platform/galileo/drivers/pwm-pca9685.c create mode 100644 platform/galileo/drivers/pwm-pca9685.h diff --git a/platform/galileo/Makefile.galileo b/platform/galileo/Makefile.galileo index ec26cf908..cd801addf 100644 --- a/platform/galileo/Makefile.galileo +++ b/platform/galileo/Makefile.galileo @@ -5,7 +5,7 @@ LIBGCC_PATH = /usr/lib/gcc/$(shell gcc -dumpmachine)/$(shell gcc -dumpversion) CONTIKI_TARGET_DIRS = . core/sys/ drivers/ CONTIKI_TARGET_MAIN = ${addprefix $(OBJECTDIR)/,contiki-main.o} -CONTIKI_SOURCEFILES += contiki-main.c clock.c rtimer-arch.c gpio-pcal9535a.c +CONTIKI_SOURCEFILES += contiki-main.c clock.c rtimer-arch.c gpio-pcal9535a.c pwm-pca9685.c PROJECT_SOURCEFILES += newlib-syscalls.c diff --git a/platform/galileo/drivers/pwm-pca9685.c b/platform/galileo/drivers/pwm-pca9685.c new file mode 100644 index 000000000..a3d93fd5c --- /dev/null +++ b/platform/galileo/drivers/pwm-pca9685.c @@ -0,0 +1,118 @@ +/* + * Copyright (C) 2015, Intel Corporation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the copyright holder nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include "i2c.h" +#include "pwm-pca9685.h" + +#define REG_MODE1 0x00 +#define REG_MODE2 0x01 + +#define REG_LED_ON_L(n) ((4 * n) + 0x06) +#define REG_LED_ON_H(n) ((4 * n) + 0x07) +#define REG_LED_OFF_L(n) ((4 * n) + 0x08) +#define REG_LED_OFF_H(n) ((4 * n) + 0x09) + +#define MAX_PWM_OUT 16 +#define PWM_ONE_PERIOD_TICKS 4096 + +int +pwm_pca9685_set_values(struct pwm_pca9685_data *data, uint32_t pwm, uint32_t on, uint32_t off) +{ + uint8_t buf[5] = { 0 }; + + if (!quarkX1000_i2c_is_available()) + return -1; + + if (pwm > MAX_PWM_OUT) + return -1; + + buf[0] = REG_LED_ON_L(pwm); + + if ((on >= PWM_ONE_PERIOD_TICKS) || (off >= PWM_ONE_PERIOD_TICKS)) { + /* Treat as 100% */ + buf[1] = 0x0; + buf[2] = (1 << 4); + buf[3] = 0x0; + buf[4] = 0x0; + } else if (off == 0) { + /* Treat it as 0% */ + buf[1] = 0x0; + buf[2] = 0x0; + buf[3] = 0x0; + buf[4] = (1 << 4); + } else { + /* Populate registers accordingly */ + buf[0] = (on & 0xFF); + buf[1] = ((on >> 8) & 0x0F); + buf[2] = (off & 0xFF); + buf[3] = ((off >> 8) & 0x0F); + } + + return quarkX1000_i2c_polling_write(buf, sizeof(buf), data->i2c_slave_addr); +} + +int +pwm_pca9685_set_duty_cycle(struct pwm_pca9685_data *data, uint32_t pwm, uint8_t duty) +{ + uint32_t on, off; + + if (duty == 0) { + on = 0; + off = 0; + } else if (duty >= 100) { + on = PWM_ONE_PERIOD_TICKS + 1; + off = PWM_ONE_PERIOD_TICKS + 1; + } else { + on = PWM_ONE_PERIOD_TICKS * duty / 100; + off = PWM_ONE_PERIOD_TICKS - 1; + } + + return pwm_pca9685_set_values(data, pwm, on, off); +} + +int +pwm_pca9685_init(struct pwm_pca9685_data *data, uint16_t i2c_slave_addr) +{ + uint8_t buf[2] = { 0 }; + + /* has to init after I2C master */ + if (!quarkX1000_i2c_is_available()) + return -1; + + data->i2c_slave_addr = i2c_slave_addr; + + buf[0] = REG_MODE1; + buf[1] = (1 << 5); + + if (quarkX1000_i2c_polling_write(buf, 2, i2c_slave_addr) < 0) + return -1; + + return 0; +} diff --git a/platform/galileo/drivers/pwm-pca9685.h b/platform/galileo/drivers/pwm-pca9685.h new file mode 100644 index 000000000..394e9357d --- /dev/null +++ b/platform/galileo/drivers/pwm-pca9685.h @@ -0,0 +1,44 @@ +/* + * Copyright (C) 2015, Intel Corporation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * 3. Neither the name of the copyright holder nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#ifndef CPU_X86_DRIVERS_PWM_PCA9685_H_ +#define CPU_X86_DRIVERS_PWM_PCA9685_H_ + +#include + +struct pwm_pca9685_data { + uint16_t i2c_slave_addr; +}; + +int pwm_pca9685_init(struct pwm_pca9685_data *data, uint16_t i2c_slave_addr); +int pwm_pca9685_set_duty_cycle(struct pwm_pca9685_data *data, uint32_t pwm, uint8_t duty); +int pwm_pca9685_set_values(struct pwm_pca9685_data *data, uint32_t pwm, uint32_t on, uint32_t off); + +#endif /* CPU_X86_DRIVERS_PWM_PCA9685_H_ */