Add virtualterminal and framebuffer support

rhempel · rhempel · commit ea0838427df3 · 2016-06-11T12:17:23.000-04:00
diff --git a/ev3dev/framebuffer.py b/ev3dev/framebuffer.py
@@ -0,0 +1,181 @@
+#!/usr/bin/env python
+
+# framebuffer.py
+#
+# Helper class for handling framebuffers for ev3dev
+
+# The MIT License (MIT)
+#
+# Copyright (c) 2016 David Lechner <david@lechnology.com>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+from ctypes import Structure, c_char, c_ulong, c_uint16, c_uint32
+from enum import Enum
+from fcntl import ioctl
+from collections import namedtuple
+
+class FrameBuffer(object):
+
+    # ioctls
+    _FBIOGET_VSCREENINFO = 0x4600
+    _FBIOGET_FSCREENINFO = 0x4602
+    _FBIOGET_CON2FBMAP = 0x460F
+
+    class Type(Enum):
+        PACKED_PIXELS = 0                   # Packed Pixels
+        PLANES = 1                          # Non interleaved planes
+        INTERLEAVED_PLANES = 2              # Interleaved planes
+        TEXT = 3                            # Text/attributes
+        VGA_PLANES = 4                      # EGA/VGA planes
+        FOURCC = 5                          # Type identified by a V4L2 FOURCC
+
+    class Visual(Enum):
+        MONO01 = 0                          # Monochrome 1=Black 0=White
+        MONO10 = 1                          # Monochrome 1=White 0=Black
+        TRUECOLOR = 2                       # True color
+        PSEUDOCOLOR = 3                     # Pseudo color (like atari)
+        DIRECTCOLOR = 4                     # Direct color
+        STATIC_PSEUDOCOLOR = 5              # Pseudo color readonly
+        FOURCC = 6                          # Visual identified by a V4L2 FOURCC
+
+    class _FixedScreenInfo(Structure):
+        _fields_ = [
+            ('id', c_char * 16),            # identification string eg "TT Builtin"
+            ('smem_start', c_ulong),        # Start of frame buffer mem (physical address)
+            ('smem_len', c_uint32),		    # Length of frame buffer mem
+            ('type', c_uint32),             # see FB_TYPE_*
+            ('type_aux', c_uint32),         # Interleave for interleaved Planes
+            ('visual', c_uint32),           # see FB_VISUAL_*
+            ('xpanstep', c_uint16),		    # zero if no hardware panning
+            ('ypanstep', c_uint16),		    # zero if no hardware panning
+            ('ywrapstep', c_uint16),        # zero if no hardware ywrap
+            ('line_length', c_uint32),      # length of a line in bytes
+            ('mmio_start', c_ulong),        # Start of Memory Mapped I/O (physical address)
+            ('mmio_len', c_uint32),         # Length of Memory Mapped I/O
+            ('accel', c_uint32),            # Indicate to driver which specific chip/card we have
+            ('capabilities', c_uint16),     # see FB_CAP_*
+            ('reserved', c_uint16 * 2),     # Reserved for future compatibility
+        ]
+
+    class _VariableScreenInfo(Structure):
+
+        class _Bitfield(Structure):
+            _fields_ = [
+                ('offset', c_uint32),       # beginning of bitfield
+                ('length', c_uint32),       # length of bitfield
+                ('msb_right', c_uint32),    # != 0 : Most significant bit is right
+            ]
+
+        _fields_ = [
+            ('xres', c_uint32),             # visible resolution
+            ('yres', c_uint32),
+            ('xres_virtual', c_uint32),     # virtual resolution
+            ('yres_virtual', c_uint32),
+            ('xoffset', c_uint32),          # offset from virtual to visible
+            ('yoffset', c_uint32),          # resolution
+            ('bits_per_pixel', c_uint32),   # guess what
+            ('grayscale', c_uint32),        # 0 = color, 1 = grayscale, >1 = FOURCC
+            ('red', _Bitfield),             # bitfield in fb mem if true color,
+            ('green', _Bitfield),           # else only length is significant
+            ('blue', _Bitfield),
+            ('transp', _Bitfield),          # transparency
+            ('nonstd', c_uint32),           # != 0 Non standard pixel format
+            ('activate', c_uint32),         # see FB_ACTIVATE_*
+            ('height', c_uint32),           # height of picture in mm
+            ('width', c_uint32),            # width of picture in mm
+            ('accel_flags', c_uint32),      # (OBSOLETE) see fb_info.flags
+            # Timing: All values, in pixclocks, except pixclock (of course)
+            ('pixclock', c_uint32),         # pixel clock in ps (pico seconds)
+            ('left_margin', c_uint32),      # time from sync to picture
+            ('right_margin', c_uint32),     # time from picture to sync
+            ('upper_margin', c_uint32),     # time from sync to picture
+            ('lower_margin', c_uint32),
+            ('hsync_len', c_uint32),        # length of horizontal sync
+            ('vsync_len', c_uint32),        # length of vertical sync
+            ('sync', c_uint32),             # see FB_SYNC_*
+            ('vmode', c_uint32),            # see FB_VMODE_*
+            ('rotate', c_uint32),           # angle we rotate counter clockwise
+            ('colorspace', c_uint32),       # colorspace for FOURCC-based modes
+            ('reserved', c_uint32 * 4),     # Reserved for future compatibility
+        ]
+
+    class _Console2FrameBufferMap(Structure):
+        _fields_ = [
+            ('console', c_uint32),
+            ('framebuffer', c_uint32),
+        ]
+
+    def __init__(self, device='/dev/fb0'):
+        self._fd = open(device, mode='r+b', buffering=0)
+        self._fixed_info = self._FixedScreenInfo()
+        ioctl(self._fd, self._FBIOGET_FSCREENINFO, self._fixed_info)
+        self._variable_info = self._VariableScreenInfo()
+        ioctl(self._fd, self._FBIOGET_VSCREENINFO, self._variable_info)
+        
+    def close(self):
+        self._fd.close()
+
+    def clear(self):
+        self._fd.seek(0)
+        self._fd.write(b'\0' * self._fixed_info.smem_len)
+
+    def write_raw(self, data):
+        self._fd.seek(0)
+        self._fd.write(data)
+
+    @staticmethod
+    def get_fb_for_console(console):
+        with open('/dev/fb0', mode='r+b') as fd:
+            m = FrameBuffer._Console2FrameBufferMap()
+            m.console = console
+            ioctl(fd, FrameBuffer._FBIOGET_CON2FBMAP, m)
+            return FrameBuffer('/dev/fb{}'.format(m.framebuffer))
+
+    @property
+    def type(self):
+        return self.Type(self._fixed_info.type)
+
+    @property
+    def visual(self):
+        return self.Visual(self._fixed_info.visual)
+
+    @property
+    def line_length(self):
+        return self._fixed_info.line_length
+
+    @property
+    def resolution(self):
+        """Visible resolution"""
+        Resolution = namedtuple('Resolution', 'x y')
+        return Resolution(self._variable_info.xres, self._variable_info.yres)
+
+    @property
+    def bits_per_pixel(self):
+        return self._variable_info.bits_per_pixel
+
+    @property
+    def grayscale(self):
+        return self._variable_info.grayscale
+
+    @property
+    def size(self):
+        """Size of picture in mm"""
+        Size = namedtuple('Size', 'width height')
+        return Size(self._variable_info.width, self._variable_info.height)
diff --git a/ev3dev/virtualterminal.py b/ev3dev/virtualterminal.py
@@ -0,0 +1,99 @@
+#!/usr/bin/env python
+
+# virtualterminal.py
+#
+# Helper class for handling framebuffers for ev3dev
+
+# The MIT License (MIT)
+#
+# Copyright (c) 2016 David Lechner <david@lechnology.com>
+#
+# Permission is hereby granted, free of charge, to any person obtaining a copy
+# of this software and associated documentation files (the "Software"), to deal
+# in the Software without restriction, including without limitation the rights
+# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+# copies of the Software, and to permit persons to whom the Software is
+# furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be included in all
+# copies or substantial portions of the Software.
+#
+# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+# SOFTWARE.
+
+from ctypes import Structure, c_char, c_short, c_ushort, c_uint
+from enum import Enum
+from fcntl import ioctl
+
+class VirtualTerminal(object):
+
+    # ioctls
+    _VT_OPENQRY = 0x5600                # find next available vt
+    _VT_GETMODE = 0x5601                # get mode of active vt
+    _VT_SETMODE = 0x5602                # set mode of active vt
+    _VT_GETSTATE = 0x5603               # get global vt state info
+    _VT_SENDSIG = 0x5604                # signal to send to bitmask of vts
+    _VT_RELDISP = 0x5605                # release display
+    _VT_ACTIVATE = 0x5606               # make vt active
+    _VT_WAITACTIVE = 0x5607             # wait for vt active
+    _VT_DISALLOCATE = 0x5608            # free memory associated to vt
+    _VT_SETACTIVATE = 0x560F            # Activate and set the mode of a console
+    _KDSETMODE = 0x4B3A                 # set text/graphics mode
+
+    class _VtMode(Structure):
+        _fields_ = [
+            ('mode', c_char),           # vt mode
+            ('waitv', c_char),          # if set, hang on writes if not active
+            ('relsig', c_short),        # signal to raise on release request
+            ('acqsig', c_short),        # signal to raise on acquisition
+            ('frsig', c_short),         # unused (set to 0)
+        ]
+
+    class VtMode(Enum):
+        AUTO = 0
+        PROCESS = 1
+        ACKACQ = 2
+
+    class _VtState(Structure):
+        _fields_ = [
+            ('v_active', c_ushort),     # active vt
+            ('v_signal', c_ushort),     # signal to send
+            ('v_state', c_ushort),      # vt bitmask
+        ]
+
+    class KdMode(Enum):
+        TEXT = 0x00
+        GRAPHICS = 0x01
+        TEXT0 = 0x02                    # obsolete
+        TEXT1 = 0x03                    # obsolete
+
+    def __init__(self):
+        self._fd = open('/dev/tty', 'r')
+
+    def close(self):
+        self._fd.close()
+
+    def get_next_available(self):
+        n = c_uint()
+        ioctl(self._fd, self._VT_OPENQRY, n)
+        return n.value
+
+    def activate(self, num):
+        ioctl(self._fd, self._VT_ACTIVATE, num)
+        ioctl(self._fd, self._VT_WAITACTIVE, num)
+
+    def get_active(self):
+        state = VirtualTerminal._VtState()
+        ioctl(self._fd, self._VT_GETSTATE, state)
+        return state.v_active
+
+    def set_graphics_mode(self):
+        ioctl(self._fd, self._KDSETMODE, self.KdMode.GRAPHICS.value)
+
+    def set_text_mode(self):
+        ioctl(self._fd, self._KDSETMODE, self.KdMode.TEXT.value)
