src/fb: cleanup gbm init logic

Signed-off-by: Edward O'Callaghan <funfunctor@folklore1984.net>

6 files changed, 77 insertions, 176 deletions

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index adc42f3..9418530 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -4,7 +4,7 @@ include_directories(${CMAKE_CURRENT_SOURCE_DIR}/)
 
 add_library(baregl_lib SHARED
 	modesetting.c
-	framebuffer.c
+	common.c
 	egl.c
 	drm.c
 )
diff --git a/src/common.c b/src/common.c
new file mode 100644
index 0000000..03bae20
--- /dev/null
+++ b/src/common.c
@@ -0,0 +1,56 @@
+#include <assert.h>
+#include <stdio.h>
+
+#include <gbm.h>
+
+#include "common.h"
+
+static struct gbm g_gbm;
+
+/**
+ * After we have found a crtc+connector+mode combination,
+ * we need to actually create a suitable framebuffer that
+ * we can use with it. There are two ways to do that:
+ *
+ *  - We create a so-called "dumb buffer"
+ *    This is a buffer that we can mmap() and every driver
+ *    supports this. We can use it for unaccelerated software
+ *    rendering on the CPU.
+ *
+ *  - We use libgbm to create buffers available for hardware
+ *    accelerated rendering. libgbm is an abstraction layer
+ *    that creates these buffers for each available DRM driver.
+ *    As there is no generic API for this, each driver provides
+ *    its own mechanism to create these buffers. We can then
+ *    use such buffers to create OpenGL contexts with the Mesa3D
+ *    library. (We do this here).
+ */
+const struct gbm * init_gbm(int drm_fd, int w, int h)
+{
+	unsigned flags = GBM_BO_USE_RENDERING | GBM_BO_USE_SCANOUT;
+	int format = GBM_FORMAT_XRGB8888;
+
+	g_gbm.dev = gbm_create_device(drm_fd);
+	if (!g_gbm.dev) {
+		fprintf(stderr, "cannot create gbm device\n");
+		return NULL;
+	}
+
+	g_gbm.surface = gbm_surface_create(g_gbm.dev, w, h, format, flags);
+	if (!g_gbm.surface) {
+		fprintf(stderr, "failed to create gbm surface\n");
+		gbm_device_destroy(g_gbm.dev);
+		g_gbm.dev = NULL;
+		return NULL;
+	}
+	g_gbm.width = w;
+	g_gbm.height = h;
+	return &g_gbm;
+}
+
+void deinit_gbm()
+{
+	assert(g_gbm.surface && g_gbm.dev);
+	gbm_surface_destroy(g_gbm.surface);
+	gbm_device_destroy(g_gbm.dev);
+}
diff --git a/src/common.h b/src/common.h
index 6c168f1..30fde55 100644
--- a/src/common.h
+++ b/src/common.h
@@ -16,6 +16,20 @@ struct render_node {
 };
 
 /**
+ * setup a backing gbm device and surface from a
+ * render node file descriptor and the expected
+ * width and height.
+ */
+struct gbm {
+	struct gbm_device *dev;
+	struct gbm_surface *surface;
+	uint32_t width, height;
+};
+
+const struct gbm * init_gbm(int drm_fd, int w, int h);
+void deinit_gbm();
+
+/**
  * ..
  */
 struct drm_fb {
diff --git a/src/framebuffer.c b/src/framebuffer.c
deleted file mode 100644
index 3f8ae2b..0000000
--- a/src/framebuffer.c
+++ /dev/null
@@ -1,160 +0,0 @@
-#include <assert.h>
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-#include <errno.h>
-#include <stdbool.h>
-#include <unistd.h>
-
-#include <sys/mman.h>
-
-#include <gbm.h>
-#include <xf86drm.h>
-#include <xf86drmMode.h>
-
-#include "common.h"
-
-
-/**
- * After we have found a crtc+connector+mode combination,
- * we need to actually create a suitable framebuffer that
- * we can use with it. There are two ways to do that:
- *
- *  - We create a so-called "dumb buffer" (We do this here).
- *    This is a buffer that we can mmap() and every driver
- *    supports this. We can use it for unaccelerated software
- *    rendering on the CPU.
- *
- *  - We use libgbm to create buffers available for hardware
- *    accelerated rendering. libgbm is an abstraction layer
- *    that creates these buffers for each available DRM driver.
- *    As there is no generic API for this, each driver provides
- *    its own mechanism to create these buffers. We can then
- *    use such buffers to create OpenGL contexts with the Mesa3D
- *    library.
- */
-static int modeset_create_dumb_fb(struct drm_fb *dev, int fd)
-{
-	struct drm_mode_create_dumb creq;
-	struct drm_mode_destroy_dumb dreq;
-	struct drm_mode_map_dumb mreq;
-	int ret;
-
-	/* create dumb buffer */
-	memset(&creq, 0, sizeof(creq));
-	creq.width = dev->width;
-	creq.height = dev->height;
-	creq.bpp = 32;
-	ret = drmIoctl(fd, DRM_IOCTL_MODE_CREATE_DUMB, &creq);
-	if (ret < 0) {
-		fprintf(stderr, "cannot create dumb buffer (%d): %m\n", errno);
-		return -errno;
-	}
-	dev->stride = creq.pitch;
-	dev->size = creq.size;
-	dev->handle = creq.handle;
-
-	/* create framebuffer object for the dumb-buffer */
-	ret = drmModeAddFB(fd, dev->width, dev->height, 24, 32, dev->stride, dev->handle, &dev->fb);
-	if (ret) {
-		fprintf(stderr, "cannot create framebuffer (%d): %m\n", errno);
-		ret = -errno;
-		goto err_destroy;
-	}
-
-	/* prepare buffer for memory mapping */
-	memset(&mreq, 0, sizeof(mreq));
-	mreq.handle = dev->handle;
-	ret = drmIoctl(fd, DRM_IOCTL_MODE_MAP_DUMB, &mreq);
-	if (ret) {
-		fprintf(stderr, "cannot map dumb buffer (%d): %m\n", errno);
-		ret = -errno;
-		goto err_fb;
-	}
-
-	/* preform the actual memory mapping */
-	dev->map = mmap(0, dev->size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, mreq.offset);
-	if (dev->map == MAP_FAILED) {
-		fprintf(stderr, "cannot mmap dumb buffer (%d): %m\n", errno);
-		ret = -errno;
-		goto err_fb;
-	}
-
-	memset(dev->map, 0, dev->size);
-
-	return 0;
-
-err_fb:
-	drmModeRmFB(fd, dev->fb);
-err_destroy:
-	memset(&dreq, 0, sizeof(dreq));
-	dreq.handle = dev->handle;
-	drmIoctl(fd, DRM_IOCTL_MODE_DESTROY_DUMB, &dreq);
-	return ret;
-}
-
-static int modeset_cleanup_dumb_fb(struct drm_fb *dev, int fd)
-{
-	struct drm_mode_destroy_dumb dreq = {0};
-
-	/* unmap buffer */
-	munmap(dev->map, dev->size);
-	/* remove framebuffer */
-	drmModeRmFB(fd, dev->fb);
-	/* delete dumb buffer */
-	dreq.handle = dev->handle;
-	drmIoctl(fd, DRM_IOCTL_MODE_DESTROY_DUMB, &dreq);
-}
-
-static int modeset_create_gbm_fb(struct drm_fb *dev, int fd)
-{
-	unsigned flags = GBM_BO_USE_RENDERING | GBM_BO_USE_SCANOUT;
-
-	int format = GBM_FORMAT_XRGB8888;
-	uint32_t bpp = 32, depth = 24;
-
-	int ret;
-       
-	struct gbm_device * gbm_dev = gbm_create_device(fd);
-	if (!gbm_dev) {
-		fprintf(stderr, "cannot create gbm device\n");
-		return -1;
-	}
-	dev->gbm_dev = gbm_dev;
-
-	dev->gbm_surface = gbm_surface_create(gbm_dev, dev->width, dev->height, format, flags);
-	if (!dev->gbm_surface) {
-		fprintf(stderr, "failed to create gbm surface\n");
-		gbm_device_destroy(gbm_dev);
-		dev->gbm_dev = NULL;
-		return -1;
-	}
-
-	return 0;
-}
-
-static int modeset_cleanup_gbm_fb(struct drm_fb *dev, int fd)
-{
-	gbm_surface_destroy(dev->gbm_surface);
-	gbm_device_destroy(dev->gbm_dev);
-}
-
-int modeset_create_fb(struct drm_fb *dev, int fd, bool is_accelerated)
-{
-	int ret;
-
-	if (is_accelerated) // do accel path
-		ret = modeset_create_gbm_fb(dev, fd);
-	else // fallback
-		ret = modeset_create_dumb_fb(dev, fd);
-
-	return ret;
-}
-
-void modeset_cleanup_fb(struct drm_fb *dev, int fd, bool is_accelerated)
-{
-	if (is_accelerated) // do accel path
-		modeset_cleanup_gbm_fb(dev, fd);
-	else // fallback
-		modeset_cleanup_dumb_fb(dev, fd);
-}
diff --git a/src/framebuffer.h b/src/framebuffer.h
deleted file mode 100644
index 3051290..0000000
--- a/src/framebuffer.h
+++ /dev/null
@@ -1,9 +0,0 @@
-#ifndef FRAMEBUFFER_H
-#define FRAMEBUFFER_H
-
-#include "common.h"
-
-int modeset_create_fb(struct drm_fb *dev, int fd, bool is_accelerated);
-void modeset_cleanup_fb(struct drm_fb *dev, int fd, bool is_accelerated);
-
-#endif /* FRAMEBUFFER_H */
diff --git a/src/modesetting.c b/src/modesetting.c
index 7860a25..61eb6bb 100644
--- a/src/modesetting.c
+++ b/src/modesetting.c
@@ -9,7 +9,6 @@
 #include <xf86drm.h>
 #include <xf86drmMode.h>
 
-#include "framebuffer.h"
 #include "modesetting.h"
 #include "egl.h"
 #include "common.h"
@@ -118,12 +117,13 @@ static int modeset_setup_dev(
 	}
 
 	/* create a framebuffer for this CRTC */
-	ret = modeset_create_fb(dev, fd, is_accelerated);
-		assert(dev->gbm_surface);
-	if (ret) {
+	struct gbm * gbm = init_gbm(fd, dev->width, dev->height);
+	if (!gbm) {
 		fprintf(stderr, "connot create framebuffer for connector %u\n", conn->connector_id);
-		return ret;
+		return -1;
 	}
+	dev->gbm_dev = gbm->dev;
+	dev->gbm_surface = gbm->surface;
 
 	return 0;
 }
@@ -236,7 +236,7 @@ void modeset_cleanup(struct display * d)
 		/* remove framebuffer */
 		/* delete dumb buffer */
 		bool is_accelerated = check_extensions(d->egl.display);
-		modeset_cleanup_fb(iter, fd, is_accelerated);
+		deinit_gbm();
 
 		/* free the removed resource */
 		free(iter);