From: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> [ Upstream commit be22203aec440c1761ce8542c2636ac6c8951e3a ] MFC v6 and v7 has no register to read min scratch buffer size, so it has to be read conditionally only if hardware supports it. This fixes following NULL pointer exception on SoCs with MFC v6/v7: 8<--- cut here --- Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = f25837f9 [00000000] *pgd=bd93d835 Internal error: Oops: 17 [#1] PREEMPT SMP ARM Modules linked in: btmrvl_sdio btmrvl bluetooth mwifiex_sdio mwifiex ecdh_generic ecc Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) PC is at s5p_mfc_get_min_scratch_buf_size+0x30/0x3c LR is at s5p_mfc_get_min_scratch_buf_size+0x28/0x3c ... [<c074f998>] (s5p_mfc_get_min_scratch_buf_size) from [<c0745bc0>] (s5p_mfc_irq+0x814/0xa5c) [<c0745bc0>] (s5p_mfc_irq) from [<c019a218>] (__handle_irq_event_percpu+0x64/0x3f8) [<c019a218>] (__handle_irq_event_percpu) from [<c019a5d8>] (handle_irq_event_percpu+0x2c/0x7c) [<c019a5d8>] (handle_irq_event_percpu) from [<c019a660>] (handle_irq_event+0x38/0x5c) [<c019a660>] (handle_irq_event) from [<c019ebc4>] (handle_fasteoi_irq+0xc4/0x180) [<c019ebc4>] (handle_fasteoi_irq) from [<c0199270>] (generic_handle_irq+0x24/0x34) [<c0199270>] (generic_handle_irq) from [<c0199888>] (__handle_domain_irq+0x7c/0xec) [<c0199888>] (__handle_domain_irq) from [<c04ac298>] (gic_handle_irq+0x58/0x9c) [<c04ac298>] (gic_handle_irq) from [<c0101ab0>] (__irq_svc+0x70/0xb0) Exception stack(0xe73ddc60 to 0xe73ddca8) ... [<c0101ab0>] (__irq_svc) from [<c01967d8>] (console_unlock+0x5a8/0x6a8) [<c01967d8>] (console_unlock) from [<c01981d0>] (vprintk_emit+0x118/0x2d8) [<c01981d0>] (vprintk_emit) from [<c01983b0>] (vprintk_default+0x20/0x28) [<c01983b0>] (vprintk_default) from [<c01989b4>] (printk+0x30/0x54) [<c01989b4>] (printk) from [<c07500b8>] (s5p_mfc_init_decode_v6+0x1d4/0x284) [<c07500b8>] (s5p_mfc_init_decode_v6) from [<c07230d0>] (vb2_start_streaming+0x24/0x150) [<c07230d0>] (vb2_start_streaming) from [<c0724e4c>] (vb2_core_streamon+0x11c/0x15c) [<c0724e4c>] (vb2_core_streamon) from [<c07478b8>] (vidioc_streamon+0x64/0xa0) [<c07478b8>] (vidioc_streamon) from [<c0709640>] (__video_do_ioctl+0x28c/0x45c) [<c0709640>] (__video_do_ioctl) from [<c0709bc8>] (video_usercopy+0x260/0x8a4) [<c0709bc8>] (video_usercopy) from [<c02b3820>] (do_vfs_ioctl+0xb0/0x9fc) [<c02b3820>] (do_vfs_ioctl) from [<c02b41a0>] (ksys_ioctl+0x34/0x58) [<c02b41a0>] (ksys_ioctl) from [<c0101000>] (ret_fast_syscall+0x0/0x28) Exception stack(0xe73ddfa8 to 0xe73ddff0) ... ---[ end trace 376cf5ba6e0bee93 ]--- Signed-off-by: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/media/platform/s5p-mfc/s5p_mfc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/media/platform/s5p-mfc/s5p_mfc.c b/drivers/media/platform/s5p-mfc/s5p_mfc.c index 9a53d3908b52..2504fe9761bf 100644 --- a/drivers/media/platform/s5p-mfc/s5p_mfc.c +++ b/drivers/media/platform/s5p-mfc/s5p_mfc.c @@ -527,7 +527,8 @@ static void s5p_mfc_handle_seq_done(struct s5p_mfc_ctx *ctx, dev); ctx->mv_count = s5p_mfc_hw_call(dev->mfc_ops, get_mv_count, dev); - ctx->scratch_buf_size = s5p_mfc_hw_call(dev->mfc_ops, + if (FW_HAS_E_MIN_SCRATCH_BUF(dev)) + ctx->scratch_buf_size = s5p_mfc_hw_call(dev->mfc_ops, get_min_scratch_buf_size, dev); if (ctx->img_width == 0 || ctx->img_height == 0) ctx->state = MFCINST_ERROR; -- 2.20.1