Add Celestica seastone dx010 psuutil.py plugins (#1781)

Author: pphuchar

device/celestica/x86_64-cel_seastone-r0/plugins/psuutil.py

@@ -0,0 +1,102 @@
+#
+# psuutil.py
+# Platform-specific PSU status interface for SONiC
+#
+
+import os.path
+
+try:
+    from sonic_psu.psu_base import PsuBase
+except ImportError as e:
+    raise ImportError(str(e) + "- required module not found")
+
+
+class PsuUtil(PsuBase):
+    """Platform-specific PSUutil class"""
+
+    def __init__(self):
+        PsuBase.__init__(self)
+        # DX010 PSU pin mapping
+        self.psu = [
+            {'base':216},           # Reserved
+            {'abs':27, 'power':22},
+            {'abs':28, 'power':25}
+        ]
+
+    def init_psu_gpio(self, pinnum):
+        # export pin, input as default
+        gpio_base = self.psu[0]['base']
+        export_file = "/sys/class/gpio/export"
+        direction_file = '/sys/class/gpio/gpio' + str(gpio_base+pinnum) + '/direction' 
+
+        try:
+            with open(export_file, 'w') as fd:
+                fd.write(str(gpio_base+pinnum))
+        except Exception as error:
+            logging.error("Unable to export gpio ", pinnum)
+
+
+    # Get a psu status and presence
+    def read_psu_statuses(self, pinnum):
+        sys_gpio_dir = "/sys/class/gpio"
+        retval = 'ERR'
+        gpio_base = self.psu[0]['base']
+
+        gpio_dir = sys_gpio_dir + '/gpio' + str(gpio_base+pinnum)
+        gpio_file = gpio_dir + "/value"
+        
+        # init gpio 
+        if (not os.path.isdir(gpio_dir)):
+            self.init_psu_gpio(pinnum)
+
+        try:
+            with open(gpio_file, 'r') as fd:
+                retval = fd.read()
+        except Exception as error:
+            logging.error("Unable to open ", gpio_file, "file !")
+
+        retval = retval.rstrip('\r\n')
+        return retval
+
+    def get_num_psus(self):
+        """
+        Retrieves the number of PSUs available on the device
+        :return: An integer, the number of PSUs available on the device
+         """
+        DX010_MAX_PSUS = 2
+        return DX010_MAX_PSUS
+
+    def get_psu_status(self, index):
+        """
+        Retrieves the oprational status of power supply unit (PSU) defined
+                by index <index>
+        :param index: An integer, index of the PSU of which to query status
+        :return: Boolean, True if PSU is operating properly, False if PSU is\
+        faulty
+        """
+        status = 0
+        psu_status = self.read_psu_statuses(self.psu[index]['power'])
+        if (psu_status != 'ERR'):
+            psu_status = int(psu_status, 10)
+            # Check for PSU status
+            if (psu_status == 1):
+                    status = 1
+
+        return status
+
+    def get_psu_presence(self, index):
+        """
+        Retrieves the presence status of power supply unit (PSU) defined
+                by index <index>
+        :param index: An integer, index of the PSU of which to query status
+        :return: Boolean, True if PSU is plugged, False if not
+        """
+        status = 0
+        psu_absence = self.read_psu_statuses(self.psu[index]['abs'])
+        if (psu_absence != 'ERR'):
+            psu_absence = (int(psu_absence, 10))
+            # Check for PSU presence
+            if (psu_absence == 0):
+                    status = 1
+
+        return status