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Diffstat (limited to 'files/common/openwrt/sensors.module_lua')
| -rw-r--r-- | files/common/openwrt/sensors.module_lua | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/files/common/openwrt/sensors.module_lua b/files/common/openwrt/sensors.module_lua new file mode 100644 index 00000000..f6c3e38c --- /dev/null +++ b/files/common/openwrt/sensors.module_lua @@ -0,0 +1,173 @@ +local base = _G +local io = require("io") +local string = require("string") +local cjson = require "cjson.safe" +local glob = require "posix.glob" +local time = require "posix.time" +local unistd = require "posix.unistd" + +local _M = {} +local _internal_ = {} +_internal_.setup = {} + +-- ############# i2c ########### + +function _internal_.write_to_file(path, data) + -- base.print(string.format("writing '%s' to '%s'", data, path)) + local f, err = io.open(path, "w") + if not f then return nil, err end + + ret, err = f:write(data) + f:close() + return ret, err +end + +function _internal_.read_from_file(path) + local f, err = io.open(path, "r") + if not f then return nil, err end + + data, err = f:read("*a") + f:close() + return data, err +end + +-- ############# i2c ########### + +function _M.i2c_bus_path(bus) + return string.format("/sys/bus/i2c/devices/i2c-%d", bus) +end + +function _M.i2c_device_name(bus, address) + return string.format("%d-%04X", bus, address) +end + +function _M.i2c_device_path(bus, address) + return string.format("/sys/bus/i2c/devices/" .. _M.i2c_device_name(bus, address)) +end + +function _M.i2c_add_device(bus, address, name) + return _internal_.write_to_file(_M.i2c_bus_path(bus) .. "/new_device", string.format("%s 0x%02X", name, address)) +end + +function _M.i2c_delete_device(bus, address) + return _internal_.write_to_file(_M.i2c_bus_path(bus) .. "/delete_device", string.format("0x%02X", address)) +end + +function _M.i2c_get_mux_channels(parent, address) + local channel_paths, glob_result = glob.glob(_M.i2c_device_path(parent, address) .. "/channel-*", 0) + if not channel_paths then + if glob_result == glob.GLOB_NOMATCH then return {} end + if glob_result == glob.GLOB_ABORTED then return nil, "glob(): aborted" end + if glob_result == glob.GLOB_NOSPACE then return nil, "glob(): no space" end + return nil, "glob(): unknown error" + end + + local channels = {} + for _, channel_path in base.pairs(channel_paths) do + local channel = string.match(channel_path, '/channel%-(%d+)$') + if not channel then return nil, "unable to parse channel number from path: " .. channel_path end + + local bus_path, err = unistd.readlink(channel_path) + if not bus_path then return nil, err end + local bus = string.match(bus_path, '/i2c%-(%d+)$') + if not bus then return nil, "unable to parse bus number from path: " .. bus_path end + + channels[tonumber(channel)] = tonumber(bus) + end + return channels +end + +function _M.i2c_add_devices_recursive(bus, devices) + local num_devices = 0 + local device + for _, device in base.ipairs(devices) do + -- base.print(string.format("i2c_add_device(%d, 0x%02X, %s)", bus, device.address, device.driver)) + _M.i2c_add_device(bus, device.address, device.driver) + num_devices = num_devices + 1 + + local setup_function = _internal_.setup[device.driver] + if setup_function ~= nil then + time.nanosleep({tv_sec = 0, tv_nsec = 100000000}) + setup_function(bus, device.address) + end + + if device.channels then + time.nanosleep({tv_sec = 0, tv_nsec = 100000000}) + local mux_channels, err = _M.i2c_get_mux_channels(bus, device.address) + if not mux_channels then return nil, error end + local channel + for _, channel in base.ipairs(device.channels) do + if not mux_channels[channel.number] then return nil, string.format("i2c-mux %s has no channel %d", _M.i2c_device_name(bus, device.address), channel.number) end + local tmp, err = _M.i2c_add_devices_recursive(mux_channels[channel.number], channel.devices) + if not tmp then return nil, err end + num_devices = num_devices + tmp + end + end + end + + return num_devices +end + + +-- ############# II0 ########### + +function _M.iio_device_path_from_i2c_device(bus, address) + local device_paths, glob_result = glob.glob(_M.i2c_device_path(bus, address) .. "/iio:device*", 0) + if not device_paths then + if glob_result == glob.GLOB_NOMATCH then return nil, "couldn't find IIO device handle for i2c device " .. _M.i2c_device_name(bus, address) end + if glob_result == glob.GLOB_ABORTED then return nil, "glob(): aborted" end + if glob_result == glob.GLOB_NOSPACE then return nil, "glob(): no space" end + return nil, "glob(): unknown error" + end + if #device_paths ~= 1 then return nil, "found more than one IIO device for i2c device " .. _M.i2c_device_name(bus, address) end + return device_paths[1] +end + +function _M.iio_setup_bmp280(bus, address) + local iio_device, err = _M.iio_device_path_from_i2c_device(bus, address) + if not iio_device then return nil, err end + + local ret, err = _internal_.write_to_file(iio_device .. '/in_pressure_oversampling_ratio', '1') + if not ret then return nil, err end + return _internal_.write_to_file(iio_device .. '/in_temp_oversampling_ratio', '1') +end +_internal_.setup['bmp280'] = _M.iio_setup_bmp280 + +function _M.iio_setup_bme280(bus, address) + local iio_device, err = _M.iio_device_path_from_i2c_device(bus, address) + if not iio_device then return nil, err end + + local ret, err = _internal_.write_to_file(iio_device .. '/in_humidityrelative_oversampling_ratio', '1') + if not ret then return nil, err end + local ret, err = _internal_.write_to_file(iio_device .. '/in_pressure_oversampling_ratio', '1') + if not ret then return nil, err end + return _internal_.write_to_file(iio_device .. '/in_temp_oversampling_ratio', '1') +end +_internal_.setup['bme280'] = _M.iio_setup_bme280 + + +-- ############# config ########### + +function _M.read_config(path) + sensors_json, err = _internal_.read_from_file(path) + if not sensors_json then return nil, err end + + return cjson.decode(sensors_json) +end + +function _M.setup(config) + local num_devices = 0 + if config.i2c then + local i2c_bus + for _, i2c_bus in ipairs(config.i2c) do + local tmp, err = _M.i2c_add_devices_recursive(i2c_bus.number, i2c_bus.devices) + if not tmp then return nil, err end + num_devices = num_devices + tmp + end + end +end + + +-- ################################ + +return _M |