Inital Commit

sources/ugreen-led-cli/i2c.cpp

@@ -0,0 +1,96 @@
+#include <linux/i2c-dev.h>
+#include <linux/i2c.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include "i2c.h"
+
+i2c_device_t::~i2c_device_t() {
+  if (_fd) close(_fd);
+}
+
+int i2c_device_t::start(const char * filename, uint16_t addr) {
+  _fd = open(filename, O_RDWR);
+
+  if (_fd < 0) {
+    int rc = _fd;
+    _fd = 0;
+    return rc;
+  }
+
+  int rc = ioctl(_fd, I2C_SLAVE, addr);
+  if (rc < 0) {
+    close(_fd);
+    _fd = 0;
+    return rc;
+  }
+
+  return 0;
+};
+
+std::vector < uint8_t > i2c_device_t::read_block_data(uint8_t command, uint32_t size) {
+  if (!_fd) return {};
+
+  if (size > I2C_SMBUS_BLOCK_MAX)
+    return {};
+
+  i2c_smbus_data smbus_data;
+  smbus_data.block[0] = size;
+
+  i2c_smbus_ioctl_data ioctl_data;
+  ioctl_data.size = I2C_SMBUS_I2C_BLOCK_DATA;
+  ioctl_data.read_write = I2C_SMBUS_READ;
+  ioctl_data.command = command;
+  ioctl_data.data = & smbus_data;
+
+  int rc = ioctl(_fd, I2C_SMBUS, & ioctl_data);
+
+  if (rc < 0) return {};
+
+  std::vector < uint8_t > data;
+  for (uint32_t i = 0; i < size; ++i)
+    data.push_back(smbus_data.block[i + 1]);
+
+  return data;
+}
+
+int i2c_device_t::write_block_data(uint8_t command, std::vector < uint8_t > data) {
+  if (!_fd) return -1;
+
+  uint32_t size = data.size();
+  if (size > I2C_SMBUS_BLOCK_MAX)
+    size = I2C_SMBUS_BLOCK_MAX;
+
+  i2c_smbus_data smbus_data;
+  smbus_data.block[0] = size;
+  for (uint32_t i = 0; i < size; ++i)
+    smbus_data.block[i + 1] = data[i];
+
+  i2c_smbus_ioctl_data ioctl_data;
+  ioctl_data.size = I2C_SMBUS_I2C_BLOCK_DATA;
+  ioctl_data.read_write = I2C_SMBUS_WRITE;
+  ioctl_data.command = command;
+  ioctl_data.data = & smbus_data;
+
+  int rc = ioctl(_fd, I2C_SMBUS, & ioctl_data);
+
+  return rc;
+}
+
+uint8_t i2c_device_t::read_byte_data(uint8_t command) {
+  if (!_fd) return {};
+
+  i2c_smbus_data smbus_data;
+
+  i2c_smbus_ioctl_data ioctl_data;
+  ioctl_data.size = I2C_SMBUS_BYTE_DATA;
+  ioctl_data.read_write = I2C_SMBUS_READ;
+  ioctl_data.command = command;
+  ioctl_data.data = & smbus_data;
+
+  int rc = ioctl(_fd, I2C_SMBUS, & ioctl_data);
+
+  if (rc < 0) return {};
+
+  return smbus_data.byte & 0xff;
+}