drm/loongson: Compute dumb-buffer sizes with drm_mode_size_dumb()

Call drm_mode_size_dumb() to compute dumb-buffer scanline pitch and
buffer size. Align the pitch according to hardware requirements.

Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Sui Jingfeng <sui.jingfeng@linux.dev>
Cc: Sui Jingfeng <sui.jingfeng@linux.dev>
Link: https://lore.kernel.org/r/20250821081918.79786-12-tzimmermann@suse.de

diff --git a/drivers/gpu/drm/loongson/lsdc_gem.c b/drivers/gpu/drm/loongson/lsdc_gem.c
index 22d0eced95da003514ef912180f62f5472e4d9e7..c29dd730a894e861a238c81f2dcf77079c395995 100644 (file)
--- a/drivers/gpu/drm/loongson/lsdc_gem.c
+++ b/drivers/gpu/drm/loongson/lsdc_gem.c
@@ -6,6 +6,7 @@
 #include <linux/dma-buf.h>
 
 #include <drm/drm_debugfs.h>
+#include <drm/drm_dumb_buffers.h>
 #include <drm/drm_file.h>
 #include <drm/drm_gem.h>
 #include <drm/drm_prime.h>
@@ -204,45 +205,31 @@ int lsdc_dumb_create(struct drm_file *file, struct drm_device *ddev,
        const struct lsdc_desc *descp = ldev->descp;
        u32 domain = LSDC_GEM_DOMAIN_VRAM;
        struct drm_gem_object *gobj;
-       size_t size;
-       u32 pitch;
-       u32 handle;
        int ret;
 
-       if (!args->width || !args->height)
-               return -EINVAL;
-
-       if (args->bpp != 32 && args->bpp != 16)
-               return -EINVAL;
-
-       pitch = args->width * args->bpp / 8;
-       pitch = ALIGN(pitch, descp->pitch_align);
-       size = pitch * args->height;
-       size = ALIGN(size, PAGE_SIZE);
+       ret = drm_mode_size_dumb(ddev, args, descp->pitch_align, 0);
+       if (ret)
+               return ret;
 
        /* Maximum single bo size allowed is the half vram size available */
-       if (size > ldev->vram_size / 2) {
-               drm_err(ddev, "Requesting(%zuMiB) failed\n", size >> 20);
+       if (args->size > ldev->vram_size / 2) {
+               drm_err(ddev, "Requesting(%zuMiB) failed\n", (size_t)(args->size >> PAGE_SHIFT));
                return -ENOMEM;
        }
 
-       gobj = lsdc_gem_object_create(ddev, domain, size, false, NULL, NULL);
+       gobj = lsdc_gem_object_create(ddev, domain, args->size, false, NULL, NULL);
        if (IS_ERR(gobj)) {
                drm_err(ddev, "Failed to create gem object\n");
                return PTR_ERR(gobj);
        }
 
-       ret = drm_gem_handle_create(file, gobj, &handle);
+       ret = drm_gem_handle_create(file, gobj, &args->handle);
 
        /* drop reference from allocate, handle holds it now */
        drm_gem_object_put(gobj);
        if (ret)
                return ret;
 
-       args->pitch = pitch;
-       args->size = size;
-       args->handle = handle;
-
        return 0;
 }