[经验]

如何使用开源硬件Banana PI BPI-R2's GPIO-s

2021-4-6 19:27:00

1493 Linux GPIO 开源硬件

BPI-R2集成MTK7623N 四核 ARM Cortex-A7 MP 支持主频1.3 ghz,BPI-R2 路由器提供丰富各种外设接口,包括 HDMI TX 高清接口, MIPI DSI 屏接口, PCIe2.0 接口, USB2.0 OTG 端口, USB3.0 端口, SATA 端口，5 千兆网口, 板载802.11a/b/g/n wifi 无线& BT4.1蓝牙 , 并且通过mini PCI-e支持 802.11ac/n WLAN
BPI-R2 系统支持 Android5.1，并完善支持 OpenWRT,Debian linux,Ubuntu linux, Raspbian 和其他嵌入式操作系统. 尺寸与BPI-R1完全一样大小, 支持 1080P y高清视频输入,40 PIN GPIO 与 Raspberry Pi 3一致.

同香蕉派其他板一样，Banana Pi BPI-R2 也有40-pin GPIO 接口:
Banana Pi BPI-R2 的40 PIN GPIO 定义与树莓派 3 一亲，下面是 Banana Pi GPIO定义:

Banana pi BPI-R2 40 PIN GPIO 定义
GPIO Pin Name	Default Function
CON1-P01	VCC-3V3
CON1-P02	VCC-5V
CON1-P03	I2C_SDA0	GPIO75
CON1-P04	VCC-5V
CON1-P05	I2C_SCL0	GPIO76
CON1-P06	GND
CON1-P07	PWM-003	GPIO206
CON1-P08	UTXD1	GPIO80
CON1-P09	GND
CON1-P10	URXD0	GPIO81
CON1-P11	URXD1	GPIO80
CON1-P12	I2S0_BCK	GPIO74
CON1-P13	UTXD0	GPIO79
CON1-P14	GND
CON1-P15	PWM-002	GPIO205
CON1-P16	URTS1	GPIO25
CON1-P17	VCC-3V3
CON1-P18	UCTS1	GPIO24
CON1-P19	SPI0_MO	GPIO56
CON1-P20	GND
CON1-P21	SPI0_MI	GPIO55
CON1-P22	PCM_CLK	GPIO18
CON1-P23	SPI0_CK	GPIO54
CON1-P24	SPI0_CSN	GPIO53
CON1-P25	GND
CON1-P26	PCM_RX	GPIO20
CON1-P27	I2C_SDA1	GPIO57
CON1-P28	I2C_SCL1	GPIO58
CON1-P29	PCM_RST	GPIO22
CON1-P30	GND
CON1-P31	SPDIF_OUT	GPIO200
CON1-P32	PCM_TX	GPIO21
CON1-P33	I2S0_MCLK	GPIO126
CON1-P34	GND
CON1-P35	I2S0_LRCK	GPIO73
CON1-P36	PCM_SYNC	GPIO19
CON1-P37	SPDIF_IN1	GPIO202
CON1-P38	I2S0_DATA_IN	GPIO72
CON1-P39	GND
CON1-P40	I2S0_DATA_OUT	GPI049

有两种方式使用R2的GPIO-s:

使用调试接口/sys/devices/platform/1000b000。pinctrl/mt_gpio，参考脚本1

使用GPIO的通用接口:/sys/class/ GPIO /export和/sys/class/ GPIO /unexport，请参考脚本2

Script 1 (it can be used on Ubuntu system with kernel 4.4.x)

--------------------
SYS_FILE=/sys/devices/platform/1000b000.pinctrl/mt_gpio
mt_gpio_mode()
{
   pin=$1
   mode=$2

   if [ ! -f ${SYS_FILE} ]; then
         exit 1
   fi

   echo "mode $pin $mode" > ${SYS_FILE}

   return 0
}

mt_gpio_dir()
{
   pin=$1
   dir=$2

   if [ "x${dir}" == "xout" ]; then
         dir_val=1
   else
         dir_val=0
   fi

   if [ ! -f ${SYS_FILE} ]; then
         exit 1
   fi

   echo "dir $pin $dir_val" > ${SYS_FILE}

   return 0
}

mt_gpio_out()
{
   pin=$1
   out=$2

   if [ ! -f ${SYS_FILE} ]; then
         exit 1
   fi

   echo "out $pin $out" > ${SYS_FILE}

   return 0
}

mt_gpio_in()
{
   pin=$1

   if [ ! -f ${SYS_FILE} ]; then
         exit 1
   fi

   echo "start $1" > ${SYS_FILE}
   result=`cat ${SYS_FILE} | grep "$1"`

   if [ "x${result}" == "x" ]; then
         echo "can't get $pin status"
         exit 2
   fi
   echo ${result}
   pin_val=`echo ${result} | awk -F ' |-' '{print $5}'`
   if [ ${pin_val} == "0" ] ; then
         return 0
   else
         return 1
   fi

   return 0

}

Script 2  (it can be used on Ubuntu system with kernel 4.4.x, and lede with kernel 4.9.x)
----------
#!/bin/ash

DIR=/sys/class/gpio/

global_gpio_offset=0

mt_gpio_init()
{
      pin=$1

      EXPORT=/sys/class/gpio/export
      UNEXPORT=/sys/class/gpio/unexport

      name=`ls $DIR | grep chip`
      if [ x${name} != x ]; then
         echo "chip id : $name"
      else
         echo "No available gpio chip"
         exit 1
      fi

      base=`cat ${DIR}/${name}/base`

      gpio_offset=`echo $((base+$pin))`
      global_gpio_offset=$gpio_offset

      if [ -d ${DIR}/gpio${gpio_offset} ]; then
         return 0
      else
         echo ${gpio_offset} > ${EXPORT}
      fi
}

mt_gpio_init $1

if [ $2 == 'dir' ]; then
      if [ $3 == 'out' ]; then
         echo out > ${DIR}/gpio${global_gpio_offset}/direction
      else
         echo in > ${DIR}/gpio${global_gpio_offset}/direction
      fi
elif [ $2 == 'val' ]; then
      if [ $# == 2 ]; then
         cat ${DIR}/gpio${global_gpio_offset}/value
      elif [ $# == 3 ]; then
         echo $3 >  ${DIR}/gpio${global_gpio_offset}/value
      fi
fi

all GPIO 定义,请参考在线文档 :

%E9%A6%99%E8%95%89%E6%B4%BE_BPI-R2#BPI-R2_GPIO_.E5.AE.9A.E4.B9.89