Untangle code and remove pylint disables

[Adafruit_Blinka-hackapet.git] / src / adafruit_blinka / microcontroller / rockchip / PWMOut.py

diff --git a/src/adafruit_blinka/microcontroller/rockchip/PWMOut.py b/src/adafruit_blinka/microcontroller/rockchip/PWMOut.py
index 6de24f44802e051c15a6b02f31c75f8791ed48b8..1e5d6e479c28ff21bc42f8d02cc4945a048e3685 100644 (file)
--- a/src/adafruit_blinka/microcontroller/rockchip/PWMOut.py
+++ b/src/adafruit_blinka/microcontroller/rockchip/PWMOut.py
@@ -1,3 +1,6 @@
+# SPDX-FileCopyrightText: 2021 Melissa LeBlanc-Williams for Adafruit Industries
+#
+# SPDX-License-Identifier: MIT

 """
 Much code from https://github.com/vsergeev/python-periphery/blob/master/periphery/pwm.py
 Copyright (c) 2015-2016 vsergeev / Ivan (Vanya) A. Sergeev
 """
 Much code from https://github.com/vsergeev/python-periphery/blob/master/periphery/pwm.py
 Copyright (c) 2015-2016 vsergeev / Ivan (Vanya) A. Sergeev


@@ -13,7 +16,8 @@ try:
 except ImportError:
     raise RuntimeError("No PWM outputs defined for this board.") from ImportError
 
 except ImportError:
     raise RuntimeError("No PWM outputs defined for this board.") from ImportError
 

-# pylint: disable=unnecessary-pass
+
+# pylint: disable=unnecessary-pass, too-many-instance-attributes

 
 
 class PWMError(IOError):
 
 
 class PWMError(IOError):


@@ -34,20 +38,9 @@ class PWMOut:
     PWM_STAT_DELAY = 0.1
 
     # Sysfs paths
     PWM_STAT_DELAY = 0.1
 
     # Sysfs paths

-    _sysfs_path = "/sys/class/pwm"

     _chip_path = "pwmchip{}"
     _channel_path = "pwm{}"
 
     _chip_path = "pwmchip{}"
     _channel_path = "pwm{}"
 

-    # Sysfs commands
-    _export = "export"
-    _unexport = "unexport"
-
-    # Pin commands
-    _pin_period = "period"
-    _pin_duty_cycle = "duty_cycle"
-    _pin_polarity = "polarity"
-    _pin_enable = "enable"
-

     def __init__(self, pwm, *, frequency=500, duty_cycle=0, variable_frequency=False):
         """Instantiate a PWM object and open the sysfs PWM corresponding to the
         specified chip and channel.
     def __init__(self, pwm, *, frequency=500, duty_cycle=0, variable_frequency=False):
         """Instantiate a PWM object and open the sysfs PWM corresponding to the
         specified chip and channel.


@@ -85,10 +78,8 @@ class PWMOut:
                 self._chip = pwmout[0][0]
                 self._channel = pwmout[0][1]
 
                 self._chip = pwmout[0][0]
                 self._channel = pwmout[0][1]
 

-        self._pwm = pwm
-

         self._chip_path = os.path.join(
         self._chip_path = os.path.join(

-            self._sysfs_path, self._chip_path.format(self._chip)
+            "/sys/class/pwm", self._chip_path.format(self._chip)

         )
         self._channel_path = os.path.join(
             self._chip_path, self._channel_path.format(self._channel)
         )
         self._channel_path = os.path.join(
             self._chip_path, self._channel_path.format(self._channel)


@@ -103,10 +94,14 @@ class PWMOut:
         if not os.path.isdir(self._channel_path):
             # Exporting the PWM.
             try:
         if not os.path.isdir(self._channel_path):
             # Exporting the PWM.
             try:

-                with open(os.path.join(self._chip_path, self._export), "w") as f_export:
+                with open(
+                    os.path.join(self._chip_path, "export"), "w", encoding="utf-8"
+                ) as f_export:

                     f_export.write("{:d}\n".format(self._channel))
             except IOError as e:
                     f_export.write("{:d}\n".format(self._channel))
             except IOError as e:

-                raise PWMError(e.errno, "Exporting PWM channel: " + e.strerror)
+                raise PWMError(
+                    e.errno, "Exporting PWM channel: " + e.strerror
+                ) from IOError

 
             # Loop until PWM is exported
             exported = False
 
             # Loop until PWM is exported
             exported = False


@@ -132,6 +127,7 @@ class PWMOut:
                     with open(
                         os.path.join(self._channel_path, "period"),
                         "w",
                     with open(
                         os.path.join(self._channel_path, "period"),
                         "w",

+                        encoding="utf-8",

                     ):
                         break
                 except IOError as e:
                     ):
                         break
                 except IOError as e:


@@ -146,6 +142,8 @@ class PWMOut:
 
             self.frequency = frequency
             self.duty_cycle = duty_cycle
 
             self.frequency = frequency
             self.duty_cycle = duty_cycle

+            self.polarity = "normal"
+            self.enable()

 
             # Cache the period for fast duty cycle updates
             self._period_ns = self._get_period_ns()
 
             # Cache the period for fast duty cycle updates
             self._period_ns = self._get_period_ns()


@@ -156,22 +154,26 @@ class PWMOut:
             # Unexporting the PWM channel
             try:
                 unexport_fd = os.open(
             # Unexporting the PWM channel
             try:
                 unexport_fd = os.open(

-                    os.path.join(self._chip_path, self._unexport), os.O_WRONLY
+                    os.path.join(self._chip_path, "unexport"), os.O_WRONLY

                 )
                 os.write(unexport_fd, "{:d}\n".format(self._channel).encode())
                 os.close(unexport_fd)
             except OSError as e:
                 )
                 os.write(unexport_fd, "{:d}\n".format(self._channel).encode())
                 os.close(unexport_fd)
             except OSError as e:

-                raise PWMError(e.errno, "Unexporting PWM: " + e.strerror)
+                raise PWMError(e.errno, "Unexporting PWM: " + e.strerror) from OSError

 
         self._chip = None
         self._channel = None
 
     def _write_channel_attr(self, attr, value):
 
         self._chip = None
         self._channel = None
 
     def _write_channel_attr(self, attr, value):

-        with open(os.path.join(self._channel_path, attr), "w") as f_attr:
+        with open(
+            os.path.join(self._channel_path, attr), "w", encoding="utf-8"
+        ) as f_attr:

             f_attr.write(value + "\n")
 
     def _read_channel_attr(self, attr):
             f_attr.write(value + "\n")
 
     def _read_channel_attr(self, attr):

-        with open(os.path.join(self._channel_path, attr), "r") as f_attr:
+        with open(
+            os.path.join(self._channel_path, attr), "r", encoding="utf-8"
+        ) as f_attr:

             return f_attr.read().strip()
 
     # Methods
             return f_attr.read().strip()
 
     # Methods


@@ -243,7 +245,7 @@ class PWMOut:
     """
 
     def _get_period_ns(self):
     """
 
     def _get_period_ns(self):

-        period_ns = self._read_channel_attr(self._pin_period)
+        period_ns = self._read_channel_attr("period")

         try:
             period_ns = int(period_ns)
         except ValueError:
         try:
             period_ns = int(period_ns)
         except ValueError:


@@ -282,7 +284,7 @@ class PWMOut:
         except ValueError:
             raise PWMError(
                 None, 'Unknown duty cycle value: "{:s}"'.format(duty_cycle_ns_str)
         except ValueError:
             raise PWMError(
                 None, 'Unknown duty cycle value: "{:s}"'.format(duty_cycle_ns_str)

-            )
+            ) from ValueError

 
         return duty_cycle_ns
 
 
         return duty_cycle_ns
 


@@ -308,7 +310,8 @@ class PWMOut:
     def _set_duty_cycle(self, duty_cycle):
         if not isinstance(duty_cycle, (int, float)):
             raise TypeError("Invalid duty cycle type, should be int or float.")
     def _set_duty_cycle(self, duty_cycle):
         if not isinstance(duty_cycle, (int, float)):
             raise TypeError("Invalid duty cycle type, should be int or float.")

-        elif not 0.0 <= duty_cycle <= 1.0:
+
+        if not 0.0 <= duty_cycle <= 1.0:

             raise ValueError("Invalid duty cycle value, should be between 0.0 and 1.0.")
 
         # Convert duty cycle from ratio to nanoseconds
             raise ValueError("Invalid duty cycle value, should be between 0.0 and 1.0.")
 
         # Convert duty cycle from ratio to nanoseconds


@@ -346,7 +349,8 @@ class PWMOut:
     def _set_polarity(self, polarity):
         if not isinstance(polarity, str):
             raise TypeError("Invalid polarity type, should be str.")
     def _set_polarity(self, polarity):
         if not isinstance(polarity, str):
             raise TypeError("Invalid polarity type, should be str.")

-        elif polarity.lower() not in ["normal", "inversed"]:
+
+        if polarity.lower() not in ["normal", "inversed"]:

             raise ValueError('Invalid polarity, can be: "normal" or "inversed".')
 
         self._write_channel_attr("polarity", polarity.lower())
             raise ValueError('Invalid polarity, can be: "normal" or "inversed".')
 
         self._write_channel_attr("polarity", polarity.lower())


@@ -365,7 +369,7 @@ class PWMOut:
 
         if enabled == "1":
             return True
 
         if enabled == "1":
             return True

-        elif enabled == "0":
+        if enabled == "0":

             return False
 
         raise PWMError(None, 'Unknown enabled value: "{:s}"'.format(enabled))
             return False
 
         raise PWMError(None, 'Unknown enabled value: "{:s}"'.format(enabled))


@@ -387,11 +391,14 @@ class PWMOut:
     # String representation
 
     def __str__(self):
     # String representation
 
     def __str__(self):

-        return "PWM {:d}, chip {:d} (period={:f} sec, duty_cycle={:f}%, polarity={:s}, enabled={:s})".format(
-            self._channel,
-            self._chip,
-            self.period,
-            self.duty_cycle * 100,
-            self.polarity,
-            str(self.enabled),
+        return (
+            "PWM {:d}, chip {:d} (period={:f} sec, duty_cycle={:f}%,"
+            " polarity={:s}, enabled={:s})".format(
+                self._channel,
+                self._chip,
+                self.period,
+                self.duty_cycle * 100,
+                self.polarity,
+                str(self.enabled),
+            )

         )
         )