[PATCH] fbdev: Add an fbdev compositor backend using pixman and evdev

Vasily Khoruzhick anarsoul at gmail.com
Wed Jan 16 13:36:25 PST 2013


On Wed, Jan 16, 2013 at 11:22 PM, David Herrmann
<dh.herrmann at googlemail.com> wrote:
> Hi Philip
>
> I like the simple design of this. I don't think we need to share much
> of the code as it's pretty simple.
>
> I haven't checked all of it, but some comments below.
>
> Thanks
> David
>
> On Tue, Jan 15, 2013 at 3:08 PM, Philip Withnall <philip at tecnocode.co.uk> wrote:
>> This is an initial version of an fbdev backend for Weston. I don't
>> consider it polished; I'm just looking for rough feedback at the
>> moment. The work is also available as a gitorious branch if anyone
>> prefers that:
>> https://gitorious.org/~pwithnall/weston/pwithnalls-weston/commits/compositor-fbdev
>>
>> One concern I have is that a lot of the input/evdev code was copied
>> verbatim from the rpi backend. It should probably be factored out into
>> evdev.c or something.
>>
>>
>> Initial version of a frame buffer backend using pixman to render to fbdev.
>> This has been tested against nouveaufb but nothing else. Much of the code
>> came straight from the rpi backend (and copyright has been attributed
>> accordingly).
>>
>> The behaviour of this backend on less modern frame buffers has yet to be
>> tested.
>>
>> Signed-off-by: Philip Withnall <philip at tecnocode.co.uk>
>> ---
>>  configure.ac           |  10 +
>>  src/Makefile.am        |  26 +-
>>  src/compositor-fbdev.c | 828 +++++++++++++++++++++++++++++++++++++++++++++++++
>>  3 files changed, 863 insertions(+), 1 deletion(-)
>>  create mode 100644 src/compositor-fbdev.c
>>
>> diff --git a/configure.ac b/configure.ac
>> index 64505dd..57a444b 100644
>> --- a/configure.ac
>> +++ b/configure.ac
>> @@ -154,6 +154,16 @@ fi
>>  AM_CONDITIONAL(INSTALL_RPI_COMPOSITOR, test "x$have_bcm_host" = "xyes")
>>
>>
>> +AC_ARG_ENABLE([fbdev-compositor], [  --enable-fbdev-compositor],,
>> +              enable_fbdev_compositor=yes)
>> +AM_CONDITIONAL([ENABLE_FBDEV_COMPOSITOR],
>> +               [test x$enable_fbdev_compositor = xyes])
>> +AS_IF([test x$enable_fbdev_compositor = xyes], [
>> +  AC_DEFINE([BUILD_FBDEV_COMPOSITOR], [1], [Build the fbdev compositor])
>> +  PKG_CHECK_MODULES([FBDEV_COMPOSITOR], [libudev >= 136 mtdev >= 1.1.0])
>> +])
>> +
>> +
>>  AC_ARG_WITH(cairo-glesv2,
>>              AS_HELP_STRING([--with-cairo-glesv2],
>>                             [Use GLESv2 cairo instead of full GL]))
>> diff --git a/src/Makefile.am b/src/Makefile.am
>> index cbfa911..efa819d 100644
>> --- a/src/Makefile.am
>> +++ b/src/Makefile.am
>> @@ -84,7 +84,8 @@ module_LTLIBRARIES =                          \
>>         $(x11_backend)                          \
>>         $(drm_backend)                          \
>>         $(wayland_backend)                      \
>> -       $(headless_backend)
>> +       $(headless_backend)                     \
>> +       $(fbdev_backend)
>>
>>  # Do not install, since the binary produced via autotools is unusable.
>>  # The real backend is built by the Android build system.
>> @@ -195,6 +196,29 @@ headless_backend_la_CFLAGS =                       \
>>  headless_backend_la_SOURCES = compositor-headless.c
>>  endif
>>
>> +if ENABLE_FBDEV_COMPOSITOR
>> +fbdev_backend = fbdev-backend.la
>> +fbdev_backend_la_LDFLAGS = -module -avoid-version
>> +fbdev_backend_la_LIBADD = \
>> +       $(COMPOSITOR_LIBS) \
>> +       $(FBDEV_COMPOSITOR_LIBS) \
>> +       ../shared/libshared.la \
>> +       $(NULL)
>
> What does that $(NULL) stuff do?
>
>> +fbdev_backend_la_CFLAGS = \
>> +       $(COMPOSITOR_CFLAGS) \
>> +       $(FBDEV_COMPOSITOR_CFLAGS) \
>> +       $(PIXMAN_CFLAGS) \
>> +       $(GCC_CFLAGS) \
>> +       $(NULL)
>
> And here
>
>> +fbdev_backend_la_SOURCES = \
>> +       compositor-fbdev.c \
>> +       tty.c \
>> +       evdev.c \
>> +       evdev.h \
>> +       evdev-touchpad.c \
>> +       $(NULL)
>
> and here
>
>> +endif
>> +
>>  if ENABLE_DESKTOP_SHELL
>>  desktop_shell = desktop-shell.la
>>  desktop_shell_la_LDFLAGS = -module -avoid-version
>> diff --git a/src/compositor-fbdev.c b/src/compositor-fbdev.c
>> new file mode 100644
>> index 0000000..f81534b
>> --- /dev/null
>> +++ b/src/compositor-fbdev.c
>> @@ -0,0 +1,828 @@
>> +/*
>> + * Copyright © 2008-2011 Kristian Høgsberg
>> + * Copyright © 2011 Intel Corporation
>> + * Copyright © 2012 Raspberry Pi Foundation
>> + * Copyright © 2013 Philip Withnall
>> + *
>> + * Permission to use, copy, modify, distribute, and sell this software and
>> + * its documentation for any purpose is hereby granted without fee, provided
>> + * that the above copyright notice appear in all copies and that both that
>> + * copyright notice and this permission notice appear in supporting
>> + * documentation, and that the name of the copyright holders not be used in
>> + * advertising or publicity pertaining to distribution of the software
>> + * without specific, written prior permission.  The copyright holders make
>> + * no representations about the suitability of this software for any
>> + * purpose.  It is provided "as is" without express or implied warranty.
>> + *
>> + * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
>> + * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
>> + * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
>> + * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
>> + * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
>> + * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
>> + * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
>> + */
>> +
>> +#define _GNU_SOURCE
>> +
>> +#include <errno.h>
>> +#include <stdlib.h>
>> +#include <stdio.h>
>> +#include <string.h>
>> +#include <math.h>
>> +#include <sys/mman.h>
>> +#include <sys/types.h>
>> +#include <fcntl.h>
>> +#include <unistd.h>
>> +#include <linux/fb.h>
>> +
>> +#include <libudev.h>
>> +
>> +#include "config.h"
>> +
>> +#include "compositor.h"
>> +#include "pixman-renderer.h"
>> +#include "evdev.h"
>> +
>> +/* Enabling this debugging incurs a significant performance hit */
>> +#if 0
>> +#define DBG(...) \
>> +       weston_log(__VA_ARGS__)
>> +#else
>> +#define DBG(...) do {} while (0)
>> +#endif
>
> I'd actually recommend to add global debugging helpers to weston and
> avoid doing this per-backend. But maybe it's ok if only used for
> debugging. Kristian should comment on that.
>
>> +
>> +struct fbdev_compositor;
>> +struct fbdev_output;
>
> I don't think this forward declaration is needed.
>
>> +
>> +struct fbdev_output {
>> +       struct fbdev_compositor *compositor;
>> +       struct weston_output base;
>> +
>> +       struct weston_mode mode;
>> +       struct wl_event_source *finish_frame_timer;
>> +
>> +       /* Frame buffer details. */
>> +       struct fb_fix_screeninfo fixed_info;
>> +       struct fb_var_screeninfo variable_info;
>> +       void *fb;
>> +       size_t fb_len;
>> +
>> +       /* pixman details. */
>> +       pixman_image_t *hw_surface;
>> +       pixman_image_t *shadow_surface;
>> +       void *shadow_buf;
>> +       uint8_t depth;
>> +};
>> +
>> +struct fbdev_seat {
>> +       struct weston_seat base;
>> +       struct wl_list devices_list;
>> +
>> +       struct udev_monitor *udev_monitor;
>> +       struct wl_event_source *udev_monitor_source;
>> +       char *seat_id;
>> +};
>> +
>> +struct fbdev_compositor {
>> +       struct weston_compositor base;
>> +       uint32_t prev_state;
>> +
>> +       struct udev *udev;
>> +       struct tty *tty;
>> +};
>> +
>> +struct fbdev_parameters {
>> +       int tty;
>> +       char *device;
>> +};
>> +
>> +static inline struct fbdev_output *
>> +to_fbdev_output(struct weston_output *base)
>> +{
>> +       return container_of(base, struct fbdev_output, base);
>> +}
>> +
>> +static inline struct fbdev_seat *
>> +to_fbdev_seat(struct weston_seat *base)
>> +{
>> +       return container_of(base, struct fbdev_seat, base);
>> +}
>> +
>> +static inline struct fbdev_compositor *
>> +to_fbdev_compositor(struct weston_compositor *base)
>> +{
>> +       return container_of(base, struct fbdev_compositor, base);
>> +}
>> +
>> +static void
>> +fbdev_output_repaint(struct weston_output *base, pixman_region32_t *damage)
>> +{
>> +       struct fbdev_output *output = to_fbdev_output(base);
>> +       struct weston_compositor *ec = output->base.compositor;
>> +       pixman_box32_t *rects;
>> +       int nrects, i, src_x, src_y, x1, y1, x2, y2, width, height;
>> +
>> +       /* Repaint the damaged region onto the back buffer. */
>> +       pixman_renderer_output_set_buffer(base, output->shadow_surface);
>> +       ec->renderer->repaint_output(base, damage);
>> +
>> +       /* Transform and composite onto the frame buffer. */
>> +       width = pixman_image_get_width(output->shadow_surface);
>> +       height = pixman_image_get_height(output->shadow_surface);
>> +       rects = pixman_region32_rectangles(damage, &nrects);
>> +
>> +       for (i = 0; i < nrects; i++) {
>> +               switch (base->transform) {
>> +               default:
>> +               case WL_OUTPUT_TRANSFORM_NORMAL:
>> +                       x1 = rects[i].x1;
>> +                       x2 = rects[i].x2;
>> +                       y1 = rects[i].y1;
>> +                       y2 = rects[i].y2;
>> +                       break;
>> +               case WL_OUTPUT_TRANSFORM_180:
>> +                       x1 = width - rects[i].x2;
>> +                       x2 = width - rects[i].x1;
>> +                       y1 = height - rects[i].y2;
>> +                       y2 = height - rects[i].y1;
>> +                       break;
>> +               case WL_OUTPUT_TRANSFORM_90:
>> +                       x1 = height - rects[i].y2;
>> +                       x2 = height - rects[i].y1;
>> +                       y1 = rects[i].x1;
>> +                       y2 = rects[i].x2;
>> +                       break;
>> +               case WL_OUTPUT_TRANSFORM_270:
>> +                       x1 = rects[i].y1;
>> +                       x2 = rects[i].y2;
>> +                       y1 = width - rects[i].x2;
>> +                       y2 = width - rects[i].x1;
>> +                       break;
>> +               }
>> +               src_x = x1;
>> +               src_y = y1;
>> +
>> +               pixman_image_composite32(PIXMAN_OP_SRC,
>> +                       output->shadow_surface, /* src */
>> +                       NULL /* mask */,
>> +                       output->hw_surface, /* dest */
>> +                       src_x, src_y, /* src_x, src_y */
>> +                       0, 0, /* mask_x, mask_y */
>> +                       x1, y1, /* dest_x, dest_y */
>> +                       x2 - x1, /* width */
>> +                       y2 - y1 /* height */);
>
> Why not pixman_blt()? You don't do any compositing here, it's a simply
> copy, right?

Only for non-rotated output, for rotated we need compositing with transform.

>> +       }
>> +
>> +       /* Update the damage region. */
>> +       pixman_region32_subtract(&ec->primary_plane.damage,
>> +                                &ec->primary_plane.damage, damage);
>> +
>> +       /* Schedule the end of the frame. TODO: Sync this to FB clock? */
>> +       wl_event_source_timer_update(output->finish_frame_timer, 10);
>
> Yeah, don't do VSync for fbdev. You could do FB_ACTIVATE_VBL or
> FBIO_WAITFORVSYNC but I don't think that we should do that for fbdev.
> If users want tear-free output, they should use DRM devices. The fbdev
> API is crappy. FBIO_WAITFORVSYNC is blocking so not suitable here and
> FB_ACTIVATE_VBL requires panning (FBIOPAN_DISPLAY) and that is
> horribly broken in most kernel drivers.
>
> I recommend just using a shadow buffer and blitting the stuff on
> repaint. The page-flip should simply be timed to the refresh-rate that
> we read below in fbdev_output_create.
>
>> +}
>> +
>> +static int
>> +finish_frame_handler(void *data)
>> +{
>> +       struct fbdev_output *output = data;
>> +       uint32_t msec;
>> +       struct timeval tv;
>> +
>> +       gettimeofday(&tv, NULL);
>> +       msec = tv.tv_sec * 1000 + tv.tv_usec / 1000;
>> +       weston_output_finish_frame(&output->base, msec);
>> +
>> +       return 1;
>> +}
>> +
>> +static int
>> +fbdev_frame_buffer_create(struct fbdev_output *output, const char *fb_dev)
>> +{
>> +       int retval = -1;
>> +       int fd = -1;
>> +
>> +       /* Open the frame buffer device. */
>> +       fd = open (fb_dev, O_RDWR);
>
> O_CLOEXEC please even though this is opened only for the time of this
> function. But you never know whether there might be other threads
> forking at the same time. Better be safe here.
>
>> +       if (fd < 0) {
>> +               weston_log("Failed to open frame buffer device ‘%s’: %s\n",
>> +                          fb_dev, strerror(errno));
>> +               goto err;
>> +       }
>> +
>> +       /* Grab the screen info. */
>> +       if (ioctl(fd, FBIOGET_FSCREENINFO, &output->fixed_info) < 0 ||
>> +           ioctl(fd, FBIOGET_VSCREENINFO, &output->variable_info) < 0) {
>> +               weston_log("Failed to get frame buffer info: %s\n",
>> +                          strerror(errno));
>> +               goto err;
>> +       }
>> +
>> +       /* Map the frame buffer. */
>> +       output->fb = mmap (NULL, output->fixed_info.smem_len,
>> +                          PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
>
> Why PROT_READ? We should never read the framebuffer data.
>
>> +       if (output->fb == NULL) {
>
> Check for MAP_FAILED instead of NULL please.
>
>> +               weston_log("Failed to mmap frame buffer: %s\n",
>> +                          strerror(errno));
>> +               goto err;
>> +       }
>> +
>> +       /* Success! */
>> +       output->fb_len = output->fixed_info.smem_len;
>> +       retval = 0;
>> +
>> +err:
>> +       if (fd >= 0)
>> +               close (fd);
>> +
>> +       return retval;
>> +}
>> +
>> +static void
>> +fbdev_frame_buffer_destroy(struct fbdev_output *output)
>> +{
>> +       if (munmap(output->fb, output->fb_len) < 0)
>> +               weston_log("Failed to munmap frame buffer: %s\n",
>> +                          strerror(errno));
>> +
>> +       output->fb = NULL;
>> +       output->fb_len = 0;
>> +}
>> +
>> +static void fbdev_output_destroy(struct weston_output *base);
>> +
>> +static int
>> +fbdev_output_create(struct fbdev_compositor *compositor,
>> +                    struct fbdev_parameters *param)
>> +{
>> +       struct fbdev_output *output;
>> +       pixman_transform_t transform;
>> +       int shadow_width, shadow_height;
>> +       int width, height;
>> +       pixman_format_code_t pixman_format;
>> +       struct wl_event_loop *loop;
>> +
>> +       output = calloc(1, sizeof *output);
>> +       if (!output)
>> +               return -1;
>> +
>> +       output->compositor = compositor;
>> +
>> +       /* Create the frame buffer. */
>> +       if (fbdev_frame_buffer_create(output, param->device) < 0) {
>> +               weston_log("Creating frame buffer failed.\n");
>> +               goto out_free;
>> +       }
>> +
>> +       /* Check its properties. TODO: Try a bit harder to support other
>> +        * formats, including setting the preferred format in the hardware. */
>> +       if (output->variable_info.bits_per_pixel != 32 ||
>> +           output->variable_info.red.offset != 16 ||
>> +           output->variable_info.red.length != 8 ||
>> +           output->variable_info.red.msb_right != 0 ||
>> +           output->variable_info.green.offset != 8 ||
>> +           output->variable_info.green.length != 8 ||
>> +           output->variable_info.green.msb_right != 0 ||
>> +           output->variable_info.blue.offset != 0 ||
>> +           output->variable_info.blue.length != 8 ||
>> +           output->variable_info.blue.msb_right != 0) {
>> +               weston_log("Frame buffer doesn't support x8r8g8b8 format.\n");
>> +               goto out_fb;
>> +       }
>
> I would recommend setting a "xrgb32 = true" flag for the output here
> and adding a fallback to the renderer path that converts xrgb32 input
> to the output-device like this:
>
> uint32_t pixel = input, out;
> uint8_t r, g, b;
>
> if (fbdev->xrgb32) {
>     out = pixel;
> } else {
>     r = (pixel >> 16) & 0xff;
>     g = (pixel >>  8) & 0xff;
>     b = (pixel >>  0) & 0xff;
>     out  = (r >> (8 - fbdev->len_r)) << fbdev->off_r;
>     out |= (g >> (8 - fbdev->len_g)) << fbdev->off_g;
>     out |= (b >> (8 - fbdev->len_b)) << fbdev->off_b;
> }
>
> This converts pixel (xrgb32) to the required output format. ALthough
> this requires the output format to be 32bits max (which sounds
> reasonable). You would have to replace the pixman_composite() with a
> for() loop to copy the data then.
>
> For instance the udlfb (DisplayLink) driver only provides rgb16
> formats so only allowing xrgb32 seems a little bit too restricting. We
> could also add dithering but that's not required now I think.
>
> The xrgb32 field guarantees a faster path for common xrgb32 devices.
> Especially if we do dithering we should special case xrgb32 to speed
> it up.
>
> Or maybe just add support for some more pixman formats. On the other
> hand, we can also add that later so xrgb32 may be ok for now.
>
>> +
>> +       pixman_format = PIXMAN_x8r8g8b8;
>
> Please also check for fixed_info->visual == FB_VISUAL_TRUECOLOR
> otherwise the red/green/blue length/offset values are not guaranteed
> to be what you expect here.
>
>> +
>> +       output->base.repaint = fbdev_output_repaint;
>> +       output->base.destroy = fbdev_output_destroy;
>> +       output->base.assign_planes = NULL;
>> +       output->base.set_backlight = NULL;
>> +       output->base.set_dpms = NULL;
>> +       output->base.switch_mode = NULL;
>> +
>> +       /* only one static mode in list */
>> +       output->mode.flags =
>> +               WL_OUTPUT_MODE_CURRENT | WL_OUTPUT_MODE_PREFERRED;
>> +       output->mode.width = output->variable_info.xres;
>> +       output->mode.height = output->variable_info.yres;
>> +       output->mode.refresh = 60000; /* 60kHz, TODO: this is a guess */
>
> You can actually try to compute that value from the fbdev information:
>
> /* calculate monitor rate, default is 60 Hz */
> uint64_t quot;
> quot = (vinfo->upper_margin + vinfo->lower_margin + vinfo->yres);
> quot *= (vinfo->left_margin + vinfo->right_margin + vinfo->xres);
> quot *= vinfo->pixclock;
> if (quot) {
>     quot = 1000000000000000LLU / quot;
>     if (!quot)
>         quot = 0;
>     else if (quot > 200000)
>         quot = 200000
>     output->mode.refresh = quot;
> } else {
>     output->mode.refresh = 60 * 1000;
> }
>
>> +       wl_list_init(&output->base.mode_list);
>> +       wl_list_insert(&output->base.mode_list, &output->mode.link);
>> +
>> +       output->base.current = &output->mode;
>> +       output->base.origin = &output->mode;
>> +       output->base.subpixel = WL_OUTPUT_SUBPIXEL_UNKNOWN;
>> +       output->base.make = "fbdev";
>> +       output->base.model = output->fixed_info.id;
>> +
>> +       weston_output_init(&output->base, &compositor->base,
>> +                          0, 0, output->variable_info.width,
>> +                          output->variable_info.height,
>> +                          WL_OUTPUT_TRANSFORM_NORMAL);
>
> Error checking?
>
>> +       /* Create a pixman image to wrap the memory mapped frame buffer. */
>> +       width = output->variable_info.xres;
>> +       height = output->variable_info.yres;
>> +
>> +       output->hw_surface =
>> +               pixman_image_create_bits(pixman_format, width, height,
>> +                                        output->fb,
>> +                                        output->fixed_info.line_length);
>
> Error checking?
>
>> +
>> +       pixman_transform_init_identity(&transform);
>> +       switch (output->base.transform) {
>> +       default:
>> +       case WL_OUTPUT_TRANSFORM_NORMAL:
>> +               shadow_width = width;
>> +               shadow_height = height;
>> +               pixman_transform_rotate(&transform,
>> +                       NULL, 0, 0);
>> +               pixman_transform_translate(&transform, NULL,
>> +                       0, 0);
>> +               break;
>> +       case WL_OUTPUT_TRANSFORM_180:
>> +               shadow_width = width;
>> +               shadow_height = height;
>> +               pixman_transform_rotate(&transform,
>> +                       NULL, -pixman_fixed_1, 0);
>> +               pixman_transform_translate(NULL, &transform,
>> +                       pixman_int_to_fixed(shadow_width),
>> +                       pixman_int_to_fixed(shadow_height));
>> +               break;
>> +       case WL_OUTPUT_TRANSFORM_270:
>> +               shadow_width = height;
>> +               shadow_height = width;
>> +               pixman_transform_rotate(&transform,
>> +                       NULL, 0, pixman_fixed_1);
>> +               pixman_transform_translate(&transform,
>> +                       NULL,
>> +                       pixman_int_to_fixed(shadow_width),
>> +                       0);
>> +               break;
>> +       case WL_OUTPUT_TRANSFORM_90:
>> +               shadow_width = height;
>> +               shadow_height = width;
>> +               pixman_transform_rotate(&transform,
>> +                       NULL, 0, -pixman_fixed_1);
>> +               pixman_transform_translate(&transform,
>> +                       NULL,
>> +                       0,
>> +                       pixman_int_to_fixed(shadow_height));
>> +               break;
>> +       }
>> +       output->shadow_buf = malloc(width * height *  (output->variable_info.bits_per_pixel / 8));
>> +       output->shadow_surface = pixman_image_create_bits(pixman_format, shadow_width, shadow_height,
>> +               output->shadow_buf, shadow_width * (output->variable_info.bits_per_pixel / 8));
>
> Error checking?
>
>> +       /* No need in transform for normal output */
>> +       if (output->base.transform != WL_OUTPUT_TRANSFORM_NORMAL)
>> +               pixman_image_set_transform(output->shadow_surface, &transform);
>> +
>> +       if (pixman_renderer_output_create(&output->base) < 0)
>> +               goto out_output;
>> +
>> +       loop = wl_display_get_event_loop(compositor->base.wl_display);
>> +       output->finish_frame_timer =
>> +               wl_event_loop_add_timer(loop, finish_frame_handler, output);
>> +
>> +       wl_list_insert(compositor->base.output_list.prev, &output->base.link);
>> +
>> +       weston_log("fbdev output %d×%d px\n",
>> +                  output->mode.width, output->mode.height);
>> +       weston_log_continue(STAMP_SPACE "guessing %d Hz and 96 dpi\n",
>> +                           output->mode.refresh / 1000);
>> +
>> +       return 0;
>> +
>> +out_output:
>> +       weston_output_destroy(&output->base);
>> +out_fb:
>> +       fbdev_frame_buffer_destroy(output);
>> +out_free:
>> +       free(output);
>> +
>> +       return -1;
>> +}
>> +
>> +static void
>> +fbdev_output_destroy(struct weston_output *base)
>> +{
>> +       struct fbdev_output *output = to_fbdev_output(base);
>> +
>> +       DBG("%s\n", __func__);
>> +
>> +       pixman_renderer_output_destroy(base);
>> +
>> +       pixman_image_unref(output->hw_surface);
>> +       output->hw_surface = NULL;
>> +
>> +       pixman_image_unref(output->shadow_surface);
>> +       output->shadow_surface = NULL;
>> +
>> +       fbdev_frame_buffer_destroy(output);
>> +
>> +       wl_list_remove(&output->base.link);
>> +       weston_output_destroy(&output->base);
>> +
>> +       free(output);
>> +}
>> +
>> +static void
>> +fbdev_led_update(struct weston_seat *seat_base, enum weston_led leds)
>> +{
>> +       struct fbdev_seat *seat = to_fbdev_seat(seat_base);
>> +       struct evdev_device *device;
>> +
>> +       wl_list_for_each(device, &seat->devices_list, link)
>> +               evdev_led_update(device, leds);
>> +}
>> +
>> +static const char default_seat[] = "seat0";
>> +
>> +static void
>> +device_added(struct udev_device *udev_device, struct fbdev_seat *master)
>> +{
>> +       struct evdev_device *device;
>> +       const char *devnode;
>> +       const char *device_seat;
>> +       int fd;
>> +
>> +       device_seat = udev_device_get_property_value(udev_device, "ID_SEAT");
>> +       if (!device_seat)
>> +               device_seat = default_seat;
>> +
>> +       if (strcmp(device_seat, master->seat_id))
>> +               return;
>> +
>> +       devnode = udev_device_get_devnode(udev_device);
>
> devnode might be NULL.
>
>> +
>> +       /* Use non-blocking mode so that we can loop on read on
>> +        * evdev_device_data() until all events on the fd are
>> +        * read.  mtdev_get() also expects this. */
>> +       fd = open(devnode, O_RDWR | O_NONBLOCK | O_CLOEXEC);
>> +       if (fd < 0) {
>> +               weston_log("opening input device '%s' failed.\n", devnode);
>> +               return;
>> +       }
>> +
>> +       device = evdev_device_create(&master->base, devnode, fd);
>> +       if (!device) {
>> +               close(fd);
>> +               weston_log("not using input device '%s'.\n", devnode);
>> +               return;
>> +       }
>> +
>> +       wl_list_insert(master->devices_list.prev, &device->link);
>> +}
>> +
>> +static void
>> +evdev_add_devices(struct udev *udev, struct weston_seat *seat_base)
>> +{
>> +       struct fbdev_seat *seat = to_fbdev_seat(seat_base);
>> +       struct udev_enumerate *e;
>> +       struct udev_list_entry *entry;
>> +       struct udev_device *device;
>> +       const char *path, *sysname;
>> +
>> +       e = udev_enumerate_new(udev);
>> +       udev_enumerate_add_match_subsystem(e, "input");
>> +       udev_enumerate_scan_devices(e);
>
> Please do error checking on all those functions here.
>
>> +       udev_list_entry_foreach(entry, udev_enumerate_get_list_entry(e)) {
>> +               path = udev_list_entry_get_name(entry);
>> +               device = udev_device_new_from_syspath(udev, path);
>> +
>> +               sysname = udev_device_get_sysname(device);
>> +               if (strncmp("event", sysname, 5) != 0) {
>> +                       udev_device_unref(device);
>> +                       continue;
>> +               }
>> +
>> +               device_added(device, seat);
>> +
>> +               udev_device_unref(device);
>> +       }
>> +       udev_enumerate_unref(e);
>> +
>> +       evdev_notify_keyboard_focus(&seat->base, &seat->devices_list);
>> +
>> +       if (wl_list_empty(&seat->devices_list)) {
>> +               weston_log(
>> +                       "warning: no input devices on entering Weston. "
>> +                       "Possible causes:\n"
>> +                       "\t- no permissions to read /dev/input/event*\n"
>> +                       "\t- seats misconfigured "
>> +                       "(Weston backend option 'seat', "
>> +                       "udev device property ID_SEAT)\n");
>> +       }
>> +}
>> +
>> +static int
>> +evdev_udev_handler(int fd, uint32_t mask, void *data)
>> +{
>> +       struct fbdev_seat *seat = data;
>> +       struct udev_device *udev_device;
>> +       struct evdev_device *device, *next;
>> +       const char *action;
>> +       const char *devnode;
>> +
>> +       udev_device = udev_monitor_receive_device(seat->udev_monitor);
>> +       if (!udev_device)
>> +               return 1;
>> +
>> +       action = udev_device_get_action(udev_device);
>> +       if (!action)
>> +               goto out;
>> +
>> +       if (strncmp("event", udev_device_get_sysname(udev_device), 5) != 0)
>> +               goto out;
>> +
>> +       if (!strcmp(action, "add")) {
>> +               device_added(udev_device, seat);
>> +       }
>> +       else if (!strcmp(action, "remove")) {
>> +               devnode = udev_device_get_devnode(udev_device);
>> +               wl_list_for_each_safe(device, next, &seat->devices_list, link)
>> +                       if (!strcmp(device->devnode, devnode)) {
>> +                               weston_log("input device %s, %s removed\n",
>> +                                          device->devname, device->devnode);
>> +                               evdev_device_destroy(device);
>> +                               break;
>> +                       }
>> +       }
>> +
>> +out:
>> +       udev_device_unref(udev_device);
>> +
>> +       return 0;
>> +}
>> +
>> +static int
>> +evdev_enable_udev_monitor(struct udev *udev, struct weston_seat *seat_base)
>> +{
>> +       struct fbdev_seat *master = to_fbdev_seat(seat_base);
>> +       struct wl_event_loop *loop;
>> +       struct weston_compositor *c = master->base.compositor;
>> +       int fd;
>> +
>> +       master->udev_monitor = udev_monitor_new_from_netlink(udev, "udev");
>> +       if (!master->udev_monitor) {
>> +               weston_log("udev: failed to create the udev monitor\n");
>> +               return 0;
>> +       }
>> +
>> +       udev_monitor_filter_add_match_subsystem_devtype(master->udev_monitor,
>> +                                                       "input", NULL);
>
> Please check for return value here, otherwise you might get all
> devices if this match-criteria cannot be added.
>
>> +
>> +       if (udev_monitor_enable_receiving(master->udev_monitor)) {
>> +               weston_log("udev: failed to bind the udev monitor\n");
>> +               udev_monitor_unref(master->udev_monitor);
>> +               return 0;
>> +       }
>> +
>> +       loop = wl_display_get_event_loop(c->wl_display);
>> +       fd = udev_monitor_get_fd(master->udev_monitor);
>> +       master->udev_monitor_source =
>> +               wl_event_loop_add_fd(loop, fd, WL_EVENT_READABLE,
>> +                                    evdev_udev_handler, master);
>> +       if (!master->udev_monitor_source) {
>> +               udev_monitor_unref(master->udev_monitor);
>> +               return 0;
>> +       }
>> +
>> +       return 1;
>> +}
>> +
>> +static void
>> +evdev_disable_udev_monitor(struct weston_seat *seat_base)
>> +{
>> +       struct fbdev_seat *seat = to_fbdev_seat(seat_base);
>> +
>> +       if (!seat->udev_monitor)
>> +               return;
>> +
>> +       udev_monitor_unref(seat->udev_monitor);
>> +       seat->udev_monitor = NULL;
>> +       wl_event_source_remove(seat->udev_monitor_source);
>> +       seat->udev_monitor_source = NULL;
>> +}
>> +
>> +static void
>> +evdev_input_create(struct weston_compositor *c, struct udev *udev,
>> +                   const char *seat_id)
>> +{
>> +       struct fbdev_seat *seat;
>> +
>> +       seat = malloc(sizeof *seat);
>> +       if (seat == NULL)
>> +               return;
>> +
>> +       memset(seat, 0, sizeof *seat);
>> +       weston_seat_init(&seat->base, c);
>> +       seat->base.led_update = fbdev_led_update;
>> +
>> +       wl_list_init(&seat->devices_list);
>> +       seat->seat_id = strdup(seat_id);
>
> Check for (!seat->seat_id) please.
>
>> +       if (!evdev_enable_udev_monitor(udev, &seat->base)) {
>> +               free(seat->seat_id);
>> +               free(seat);
>> +               return;
>> +       }
>> +
>> +       evdev_add_devices(udev, &seat->base);
>> +}
>> +
>> +static void
>> +evdev_remove_devices(struct weston_seat *seat_base)
>> +{
>> +       struct fbdev_seat *seat = to_fbdev_seat(seat_base);
>> +       struct evdev_device *device, *next;
>> +
>> +       wl_list_for_each_safe(device, next, &seat->devices_list, link)
>> +               evdev_device_destroy(device);
>> +
>> +       if (seat->base.seat.keyboard)
>> +               notify_keyboard_focus_out(&seat->base);
>> +}
>> +
>> +static void
>> +evdev_input_destroy(struct weston_seat *seat_base)
>> +{
>> +       struct fbdev_seat *seat = to_fbdev_seat(seat_base);
>> +
>> +       evdev_remove_devices(seat_base);
>> +       evdev_disable_udev_monitor(&seat->base);
>> +
>> +       weston_seat_release(seat_base);
>> +       free(seat->seat_id);
>> +       free(seat);
>> +}
>> +
>> +static void
>> +fbdev_compositor_destroy(struct weston_compositor *base)
>> +{
>> +       struct fbdev_compositor *compositor = to_fbdev_compositor(base);
>> +       struct weston_seat *seat, *next;
>> +
>> +       /* Destroy all inputs. */
>> +       wl_list_for_each_safe(seat, next, &compositor->base.seat_list, link)
>> +               evdev_input_destroy(seat);
>> +
>> +       /* Destroy the output. */
>> +       weston_compositor_shutdown(&compositor->base);
>> +
>> +       /* Chain up. */
>> +       compositor->base.renderer->destroy(&compositor->base);
>> +       tty_destroy(compositor->tty);
>> +
>> +       free(compositor);
>> +}
>> +
>> +static void
>> +vt_func(struct weston_compositor *base, int event)
>> +{
>> +       struct fbdev_compositor *compositor = to_fbdev_compositor(base);
>> +       struct weston_seat *seat;
>> +       struct weston_output *output;
>> +
>> +       switch (event) {
>> +       case TTY_ENTER_VT:
>> +               weston_log("entering VT\n");
>> +               compositor->base.focus = 1;
>> +               compositor->base.state = compositor->prev_state;
>> +               weston_compositor_damage_all(&compositor->base);
>> +               wl_list_for_each(seat, &compositor->base.seat_list, link) {
>> +                       evdev_add_devices(compositor->udev, seat);
>> +                       evdev_enable_udev_monitor(compositor->udev, seat);
>> +               }
>> +               break;
>> +       case TTY_LEAVE_VT:
>> +               weston_log("leaving VT\n");
>> +               wl_list_for_each(seat, &compositor->base.seat_list, link) {
>> +                       evdev_disable_udev_monitor(seat);
>> +                       evdev_remove_devices(seat);
>> +               }
>> +
>> +               compositor->base.focus = 0;
>> +               compositor->prev_state = compositor->base.state;
>> +               compositor->base.state = WESTON_COMPOSITOR_SLEEPING;
>> +
>> +               /* If we have a repaint scheduled (from the idle handler), make
>> +                * sure we cancel that so we don't try to pageflip when we're
>> +                * vt switched away.  The SLEEPING state will prevent
>> +                * further attemps at repainting.  When we switch
>> +                * back, we schedule a repaint, which will process
>> +                * pending frame callbacks. */
>> +
>> +               wl_list_for_each(output,
>> +                                &compositor->base.output_list, link) {
>> +                       output->repaint_needed = 0;
>> +               }
>> +
>> +               break;
>> +       };
>> +}
>> +
>> +static void
>> +fbdev_restore(struct weston_compositor *base)
>> +{
>> +       struct fbdev_compositor *compositor = to_fbdev_compositor(base);
>> +
>> +       tty_reset(compositor->tty);
>> +}
>> +
>> +static void
>> +switch_vt_binding(struct wl_seat *seat, uint32_t time, uint32_t key, void *data)
>> +{
>> +       struct fbdev_compositor *ec = data;
>> +
>> +       tty_activate_vt(ec->tty, key - KEY_F1 + 1);
>> +}
>> +
>> +static struct weston_compositor *
>> +fbdev_compositor_create(struct wl_display *display, int argc, char *argv[],
>> +                        const char *config_file, struct fbdev_parameters *param)
>> +{
>> +       struct fbdev_compositor *compositor;
>> +       const char *seat = default_seat;
>> +       uint32_t key;
>> +
>> +       weston_log("initializing fbdev backend\n");
>> +
>> +       compositor = calloc(1, sizeof *compositor);
>> +       if (compositor == NULL)
>> +               return NULL;
>> +
>> +       if (weston_compositor_init(&compositor->base, display, argc, argv,
>> +                                  config_file) < 0)
>> +               goto out_free;
>> +
>> +       compositor->udev = udev_new();
>> +       if (compositor->udev == NULL) {
>> +               weston_log("Failed to initialize udev context.\n");
>> +               goto out_compositor;
>> +       }
>> +
>> +       /* Set up the TTY. */
>> +       compositor->tty = tty_create(&compositor->base, vt_func, param->tty);
>> +       if (!compositor->tty) {
>> +               weston_log("Failed to initialize tty.\n");
>> +               goto out_udev;
>> +       }
>> +
>> +       compositor->base.destroy = fbdev_compositor_destroy;
>> +       compositor->base.restore = fbdev_restore;
>> +
>> +       compositor->base.focus = 1;
>> +       compositor->prev_state = WESTON_COMPOSITOR_ACTIVE;
>> +
>> +       for (key = KEY_F1; key < KEY_F9; key++)
>> +               weston_compositor_add_key_binding(&compositor->base, key,
>> +                                                 MODIFIER_CTRL | MODIFIER_ALT,
>> +                                                 switch_vt_binding,
>> +                                                 compositor);
>> +
>> +       if (pixman_renderer_init(&compositor->base) < 0)
>> +               goto out_tty;
>> +
>> +       if (fbdev_output_create(compositor, param) < 0)
>> +               goto out_pixman;
>> +
>> +       evdev_input_create(&compositor->base, compositor->udev, seat);
>> +
>> +       return &compositor->base;
>> +
>> +out_pixman:
>> +       compositor->base.renderer->destroy(&compositor->base);
>> +
>> +out_tty:
>> +       tty_destroy(compositor->tty);
>> +
>> +out_udev:
>> +       udev_unref(compositor->udev);
>> +
>> +out_compositor:
>> +       weston_compositor_shutdown(&compositor->base);
>> +
>> +out_free:
>> +       free(compositor);
>> +
>> +       return NULL;
>> +}
>> +
>> +WL_EXPORT struct weston_compositor *
>> +backend_init(struct wl_display *display, int argc, char *argv[],
>> +            const char *config_file)
>> +{
>> +       struct fbdev_parameters param = {
>> +               .tty = 0, /* default to current tty */
>> +               .device = "/dev/fb0", /* default frame buffer */
>
> Why not discover that device via udev? That would avoid any hard-coded
> paths. And you could do an fbdev_output_create() on all fbdev devices
> you find.
>
>> +       };
>> +
>> +       const struct weston_option fbdev_options[] = {
>> +               { WESTON_OPTION_INTEGER, "tty", 0, &param.tty },
>> +               { WESTON_OPTION_STRING, "device", 0, &param.device },
>> +       };
>> +
>> +       parse_options(fbdev_options, ARRAY_LENGTH(fbdev_options), argc, argv);
>> +
>> +       return fbdev_compositor_create(display, argc, argv, config_file,
>> +                                      &param);
>> +}
>> --
>> 1.7.11.7
>>
>>
>> _______________________________________________
>> wayland-devel mailing list
>> wayland-devel at lists.freedesktop.org
>> http://lists.freedesktop.org/mailman/listinfo/wayland-devel
>>
> _______________________________________________
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> wayland-devel at lists.freedesktop.org
> http://lists.freedesktop.org/mailman/listinfo/wayland-devel


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