X-Git-Url: https://git.ayoreis.com/Adafruit_Blinka-hackapet.git/blobdiff_plain/c72b2913f8b11bc650b5a17f087a058cf7948fb9..b5c457265c44ac26be4f44b68b02944bb9869416:/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py diff --git a/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py b/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py index 118d27c..3cfb46b 100644 --- a/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py +++ b/src/adafruit_blinka/microcontroller/mcp2221/mcp2221.py @@ -1,6 +1,40 @@ +import os import time import hid +# Small values seem to help on some Windows setups +MCP2221_HID_DELAY = float(os.environ.get('BLINKA_MCP2221_HID_DELAY', 0)) +# Windows also seems to want some time after a reset +MCP2221_RESET_DELAY = float(os.environ.get('BLINKA_MCP2221_RESET_DELAY', 0.1)) + +# from the C driver +# http://ww1.microchip.com/downloads/en/DeviceDoc/mcp2221_0_1.tar.gz +# others (???) determined during driver developement +# pylint: disable=bad-whitespace +RESP_ERR_NOERR = 0x00 +RESP_ADDR_NACK = 0x25 +RESP_READ_ERR = 0x7F +RESP_READ_COMPL = 0x55 +RESP_READ_PARTIAL = 0x54 # ??? +RESP_I2C_IDLE = 0x00 +RESP_I2C_START_TOUT = 0x12 +RESP_I2C_RSTART_TOUT = 0x17 +RESP_I2C_WRADDRL_TOUT = 0x23 +RESP_I2C_WRADDRL_WSEND = 0x21 +RESP_I2C_WRADDRL_NACK = 0x25 +RESP_I2C_WRDATA_TOUT = 0x44 +RESP_I2C_RDDATA_TOUT = 0x52 +RESP_I2C_STOP_TOUT = 0x62 + +RESP_I2C_MOREDATA = 0x43 # ??? +RESP_I2C_PARTIALDATA = 0x41 # ??? +RESP_I2C_WRITINGNOSTOP = 0x45 # ??? + +MCP2221_RETRY_MAX = 50 +MCP2221_MAX_I2C_DATA_LEN = 60 +MASK_ADDR_NACK = 0x40 +# pylint: enable=bad-whitespace + class MCP2221: VID = 0x04D8 @@ -15,12 +49,14 @@ class MCP2221: def __init__(self): self._hid = hid.device() self._hid.open(MCP2221.VID, MCP2221.PID) + self._reset() def _hid_xfer(self, report, response=True): # first byte is report ID, which =0 for MCP2221 # remaing bytes = 64 byte report data # https://github.com/libusb/hidapi/blob/083223e77952e1ef57e6b77796536a3359c1b2a3/hidapi/hidapi.h#L185 self._hid.write(b'\0' + report + b'\0'*(64-len(report))) + time.sleep(MCP2221_HID_DELAY) if response: # return is 64 byte response report return self._hid.read(64) @@ -29,13 +65,13 @@ class MCP2221: # MISC #---------------------------------------------------------------- def gp_get_mode(self, pin): - return self._hid_xfer(bytes([0x61]))[22+pin] & 0x07 + return self._hid_xfer(b'\x61')[22+pin] & 0x07 def gp_set_mode(self, pin, mode): # get current settings - current = self._hid_xfer(bytes([0x61])) + current = self._hid_xfer(b'\x61') # empty report, this is safe since 0's = no change - report = bytearray([0x60]+[0]*63) + report = bytearray(b'\x60'+b'\x00'*63) # set the alter GP flag byte report[7] = 0xFF # each pin can be set individually @@ -63,35 +99,44 @@ class MCP2221: print() def _status_dump(self): - self._pretty_report(self._hid_xfer(bytes([0x10]))) + self._pretty_report(self._hid_xfer(b'\x10')) def _sram_dump(self): - self._pretty_report(self._hid_xfer(bytes([0x61]))) + self._pretty_report(self._hid_xfer(b'\x61')) def _reset(self): self._hid_xfer(b'\x70\xAB\xCD\xEF', response=False) - time.sleep(1) - self._hid.open(MCP2221.VID, MCP2221.PID) + time.sleep(MCP2221_RESET_DELAY) + start = time.monotonic() + while time.monotonic() - start < 5: + try: + self._hid.open(MCP2221.VID, MCP2221.PID) + except OSError: + # try again + time.sleep(0.1) + continue + return + raise OSError("open failed") #---------------------------------------------------------------- # GPIO #---------------------------------------------------------------- def gpio_set_direction(self, pin, mode): - report = bytearray([0x50]+[0]*63) # empty set GPIO report + report = bytearray(b'\x50'+b'\x00'*63) # empty set GPIO report offset = 4 * (pin + 1) - report[offset] = 0x01 # set pin direction - report[offset+1] = mode # to this + report[offset] = 0x01 # set pin direction + report[offset+1] = mode # to this self._hid_xfer(report) def gpio_set_pin(self, pin, value): - report = bytearray([0x50]+[0]*63) # empty set GPIO report + report = bytearray(b'\x50'+b'\x00'*63) # empty set GPIO report offset = 2 + 4 * pin - report[offset] = 0x01 # set pin value - report[offset+1] = value # to this + report[offset] = 0x01 # set pin value + report[offset+1] = value # to this self._hid_xfer(report) def gpio_get_pin(self, pin): - resp = self._hid_xfer(bytes([0x51])) + resp = self._hid_xfer(b'\x51') offset = 2 + 2 * pin if resp[offset] == 0xEE: raise RuntimeError("Pin is not set for GPIO operation.") @@ -100,22 +145,124 @@ class MCP2221: #---------------------------------------------------------------- # I2C - # - # cribbed from the C driver: - # define RESP_ERR_NOERR 0x00 - # define RESP_ADDR_NACK 0x25 - # define RESP_READ_ERR 0x7F - # define RESP_READ_COMPL 0x55 - # define RESP_I2C_IDLE 0x00 - # define RESP_I2C_START_TOUT 0x12 - # define RESP_I2C_RSTART_TOUT 0x17 - # define RESP_I2C_WRADDRL_TOUT 0x23 - # define RESP_I2C_WRADDRL_WSEND 0x21 - # define RESP_I2C_WRADDRL_NACK 0x25 - # define RESP_I2C_WRDATA_TOUT 0x44 - # define RESP_I2C_RDDATA_TOUT 0x52 - # define RESP_I2C_STOP_TOUT 0x62 #---------------------------------------------------------------- + def _i2c_status(self): + resp = self._hid_xfer(b'\x10') + if resp[1] != 0: + raise RuntimeError("Couldn't get I2C status") + return resp + + def _i2c_state(self): + return self._i2c_status()[8] + + def _i2c_cancel(self): + resp = self._hid_xfer(b'\x10\x00\x10') + if resp[1] != 0x00: + raise RuntimeError("Couldn't cancel I2C") + if resp[2] == 0x10: + # bus release will need "a few hundred microseconds" + time.sleep(0.001) + + def _i2c_write(self, cmd, address, buffer, start=0, end=None): + if self._i2c_state() != 0x00: + self._i2c_cancel() + + end = end if end else len(buffer) + length = end - start + retries = 0 + + while (end - start) > 0: + chunk = min(end - start, MCP2221_MAX_I2C_DATA_LEN) + # write out current chunk + resp = self._hid_xfer(bytes([cmd, + length & 0xFF, + (length >> 8) & 0xFF, + address << 1]) + + buffer[start:(start+chunk)]) + # check for success + if resp[1] != 0x00: + if resp[2] in (RESP_I2C_START_TOUT, + RESP_I2C_WRADDRL_TOUT, + RESP_I2C_WRADDRL_NACK, + RESP_I2C_WRDATA_TOUT, + RESP_I2C_STOP_TOUT): + raise RuntimeError("Unrecoverable I2C state failure") + retries += 1 + if retries >= MCP2221_RETRY_MAX: + raise RuntimeError("I2C write error, max retries reached.") + time.sleep(0.001) + continue # try again + # yay chunk sent! + while self._i2c_state() == RESP_I2C_PARTIALDATA: + time.sleep(0.001) + start += chunk + retries = 0 + + # check status in another loop + for _ in range(MCP2221_RETRY_MAX): + status = self._i2c_status() + if status[20] & MASK_ADDR_NACK: + raise RuntimeError("I2C slave address was NACK'd") + usb_cmd_status = status[8] + if usb_cmd_status == 0: + break + if usb_cmd_status == RESP_I2C_WRITINGNOSTOP and cmd == 0x94: + break # this is OK too! + if usb_cmd_status in (RESP_I2C_START_TOUT, + RESP_I2C_WRADDRL_TOUT, + RESP_I2C_WRADDRL_NACK, + RESP_I2C_WRDATA_TOUT, + RESP_I2C_STOP_TOUT): + raise RuntimeError("Unrecoverable I2C state failure") + time.sleep(0.001) + else: + raise RuntimeError("I2C write error: max retries reached.") + # whew success! + + def _i2c_read(self, cmd, address, buffer, start=0, end=None): + if self._i2c_state() not in (RESP_I2C_WRITINGNOSTOP, 0): + self._i2c_cancel() + + end = end if end else len(buffer) + length = end - start + + # tell it we want to read + resp = self._hid_xfer(bytes([cmd, + length & 0xFF, + (length >> 8) & 0xFF, + (address << 1) | 0x01])) + + # check for success + if resp[1] != 0x00: + raise RuntimeError("Unrecoverable I2C read failure") + + # and now the read part + while (end - start) > 0: + for retry in range(MCP2221_RETRY_MAX): + # the actual read + resp = self._hid_xfer(b'\x40') + # check for success + if resp[1] == RESP_I2C_PARTIALDATA: + time.sleep(0.001) + continue + if resp[1] != 0x00: + raise RuntimeError("Unrecoverable I2C read failure") + if resp[2] == RESP_ADDR_NACK: + raise RuntimeError("I2C NACK") + if resp[3] == 0x00 and resp[2] == 0x00: + break + if resp[3] == RESP_READ_ERR: + time.sleep(0.001) + continue + if resp[2] in (RESP_READ_COMPL, RESP_READ_PARTIAL): + break + + # move data into buffer + chunk = min(end - start, 60) + for i, k in enumerate(range(start, start+chunk)): + buffer[k] = resp[4 + i] + start += chunk + def i2c_configure(self, baudrate=100000): self._hid_xfer(bytes([0x10, # set parameters 0x00, # don't care @@ -124,103 +271,51 @@ class MCP2221: 12000000 // baudrate - 3])) def i2c_writeto(self, address, buffer, *, start=0, end=None): - end = end if end else len(buffer) - self._hid_xfer(bytes([0x90, # i2c write data - end - start & 0xFF, # xfer length lo byte - end - start >> 8 & 0xFF, # xfer length hi byte - address << 1]) + # i2c slave address - buffer[start:end]) # user data to be sent + self._i2c_write(0x90, address, buffer, start, end) def i2c_readfrom_into(self, address, buffer, *, start=0, end=None): - end = end if end else len(buffer) - retries = 0 - while retries < 5: - # - # why does this require two xfers? - # - # 1. tell it we want to read - self._hid_xfer(bytes([0x91, # i2c read data - end - start & 0xFF, # xfer length lo byte - end - start >> 8 & 0xFF, # xfer length hi byte - address << 1 | 0x01])) # i2c slave address - # 2. and then actually read - response = self._hid_xfer(bytes([0x40])) - # check for success - if response[1] == 0x00: - break - retries += 1 - if retries >= 5: - raise RuntimeError("I2C read error, max retries reached.") - # move data into buffer - for i in range(end - start): - buffer[start + i] = response[4 + i] + self._i2c_read(0x91, address, buffer, start, end) def i2c_writeto_then_readfrom(self, address, out_buffer, in_buffer, *, out_start=0, out_end=None, in_start=0, in_end=None): - out_end = out_end if out_end else len(buffer_out) - in_end = in_end if in_end else len(buffer_in) - self._hid_xfer(bytes([0x94, # i2c write data no stop - out_end - out_start & 0xFF, # xfer length lo byte - out_end - out_start >> 8 & 0xFF, # xfer length hi byte - address << 1]) + # i2c slave address - out_buffer[out_start:out_end]) # user data to be sent - retries = 5 - while retries < 5: - # - # why does this require two xfers? - # - # 1. tell it we want to read - self._hid_xfer(bytes([0x93, # i2c read data repeated start - in_end - in_start & 0xFF, # xfer length lo byte - in_end - in_start >> 8 & 0xFF, # xfer length hi byte - address << 1 | 0x01])) # i2c slave address - # 2. and then actually read - response = self._hid_xfer(bytes([0x40])) - # check for success - if response[1] == 0x00: - break - retries += 1 - if retries >= 5: - raise RuntimeError("I2C read error, max retries reached.") - # move data into buffer - for i in range(in_end - in_start): - in_buffer[in_start + i] = response[4 + i] + self._i2c_write(0x94, address, out_buffer, out_start, out_end) + self._i2c_read(0x93, address, in_buffer, in_start, in_end) def i2c_scan(self, *, start=0, end=0x79): found = [] for addr in range(start, end+1): # try a write - self.i2c_writeto(addr, b'\x00') + try: + self.i2c_writeto(addr, b'\x00') + except RuntimeError: # no reply! + continue # store if success - if self._hid_xfer(b'\x10')[8] == 0x00: - found.append(addr) - # cancel and continue - self._hid_xfer(b'\x10\x00\x10') + found.append(addr) return found #---------------------------------------------------------------- # ADC #---------------------------------------------------------------- def adc_configure(self, vref=0): - report = bytearray([0x60]+[0]*63) + report = bytearray(b'\x60'+b'\x00'*63) report[5] = 1 << 7 | (vref & 0b111) self._hid_xfer(report) def adc_read(self, pin): - resp = self._hid_xfer(bytes([0x10])) + resp = self._hid_xfer(b'\x10') return resp[49 + 2 * pin] << 8 | resp[48 + 2 * pin] #---------------------------------------------------------------- # DAC #---------------------------------------------------------------- def dac_configure(self, vref=0): - report = bytearray([0x60]+[0]*63) + report = bytearray(b'\x60'+b'\x00'*63) report[3] = 1 << 7 | (vref & 0b111) self._hid_xfer(report) def dac_write(self, pin, value): - report = bytearray([0x60]+[0]*63) + report = bytearray(b'\x60'+b'\x00'*63) report[4] = 1 << 7 | (value & 0b11111) self._hid_xfer(report)