From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752121AbeDJBkr (ORCPT ); Mon, 9 Apr 2018 21:40:47 -0400 Received: from mail-pl0-f67.google.com ([209.85.160.67]:40697 "EHLO mail-pl0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751543AbeDJBkp (ORCPT ); Mon, 9 Apr 2018 21:40:45 -0400 X-Google-Smtp-Source: AIpwx4/NWRJ1QOt6WDKk+yv3oRYzVMvWvk3kvnaPj62yX6PtuLpjEkW5eqB7Jc/k2sjjoUzjJrx6ug== From: Jia-Ju Bai To: paulus@samba.org, b.zolnierkie@samsung.com Cc: linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org, Jia-Ju Bai Subject: [PATCH] video: fbdev: aty: aty128fb: Replace mdelay with msleep in aty128_set_suspend Date: Tue, 10 Apr 2018 09:40:35 +0800 Message-Id: <1523324435-28719-1-git-send-email-baijiaju1990@gmail.com> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org aty128_set_suspend() is never called in atomic context. The call chains ending up at aty128_set_suspend() are: [1] aty128_set_suspend() <- aty128_pci_suspend() [2] aty128_set_suspend() <- aty128_do_resume() <- aty128_pci_resume() [3] aty128_set_suspend() <- aty128_do_resume() <- aty128_early_resume() aty128_pci_suspend() is set as ".suspend" in struct pci_driver. aty128_pci_resume() is set as ".resume" in struct pci_driver. aty128_early_resume() is never called. These functions are not called in atomic context. Despite never getting called from atomic context, aty128_set_suspend() calls mdelay() to busily wait. This is not necessary and can be replaced with msleep() to avoid busy waiting. This is found by a static analysis tool named DCNS written by myself. And I also manually check it. Signed-off-by: Jia-Ju Bai --- drivers/video/fbdev/aty/aty128fb.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/video/fbdev/aty/aty128fb.c b/drivers/video/fbdev/aty/aty128fb.c index db18474..15dfdff 100644 --- a/drivers/video/fbdev/aty/aty128fb.c +++ b/drivers/video/fbdev/aty/aty128fb.c @@ -2442,7 +2442,7 @@ static void aty128_set_suspend(struct aty128fb_par *par, int suspend) (void)aty_ld_pll(POWER_MANAGEMENT); aty_st_le32(BUS_CNTL1, 0x00000010); aty_st_le32(MEM_POWER_MISC, 0x0c830000); - mdelay(100); + msleep(100); /* Switch PCI power management to D2 */ pci_set_power_state(pdev, PCI_D2); -- 1.9.1