From d352778979d2eed09e266ed0f3a5e3ccd3983940 Mon Sep 17 00:00:00 2001 From: Ahmet Sezgin Duran Date: Thu, 21 May 2026 20:44:25 +0000 Subject: [PATCH] staging: sm750fb: gate dualview dataflow using g_dualview In sm750fb_setup and sm750fb_set_drv functions, the dualview related code is guarded by `sm750_dev->fb_count > 1` condition. That value is updated only after each framebuffer is registered, while both guards are used before any increment. Current flow: lynxfb_pci_probe() sm750fb_setup() // fb_count is 0 for each fb: sm750fb_framebuffer_alloc() lynxfb_set_fbinfo() sm750fb_set_drv() // fb_count is 0 or 1 register_framebuffer() sm750_dev->fb_count++; // fb_count is incremented Thus even if `dualview=1` parameter is passed down to the driver, fb_count is never > 1 at either check, so dualview dataflows are not selected and crtc->vidmem_size is never halved. Use `g_dualview` global variable instead of fb_count > 1 to correctly enable dualview capabilities. Fixes: a3f92cc94c61 ("staging: sm750fb: replace dual member of sm750_dev with fb_count") Signed-off-by: Ahmet Sezgin Duran Link: https://patch.msgid.link/20260521204425.82627-1-ahmet@sezginduran.net Signed-off-by: Greg Kroah-Hartman --- drivers/staging/sm750fb/sm750.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/staging/sm750fb/sm750.c b/drivers/staging/sm750fb/sm750.c index 89c811e0806c..3a4b9c06f770 100644 --- a/drivers/staging/sm750fb/sm750.c +++ b/drivers/staging/sm750fb/sm750.c @@ -591,7 +591,7 @@ static int sm750fb_set_drv(struct lynxfb_par *par) crtc = &par->crtc; crtc->vidmem_size = sm750_dev->vidmem_size; - if (sm750_dev->fb_count > 1) + if (g_dualview) crtc->vidmem_size >>= 1; /* setup crtc and output member */ @@ -896,7 +896,7 @@ static void sm750fb_setup(struct sm750_dev *sm750_dev, char *src) NO_PARAM: if (sm750_dev->revid != SM750LE_REVISION_ID) { - if (sm750_dev->fb_count > 1) { + if (g_dualview) { if (swap) sm750_dev->dataflow = sm750_dual_swap; else