From: Arnd Bergmann <arnd@arndb.de>
To: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>,
        David Airlie <airlied@linux.ie>
Cc: Arnd Bergmann <arnd@arndb.de>, Daniel Vetter <daniel.vetter@ffwll.ch>,
        =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= 
        <ville.syrjala@linux.intel.com>,
        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org
Subject: [PATCH] drm: gma500: fix logic error
Date: Tue,  5 Sep 2017 09:47:26 +0200
Message-Id: <20170905074741.435324-1-arnd@arndb.de>
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1165
Lines: 30

gcc-8 points out a condition that almost certainly doesn't
do what the author had in mind:

drivers/gpu/drm/gma500/mdfld_intel_display.c: In function 'mdfldWaitForPipeEnable':
drivers/gpu/drm/gma500/mdfld_intel_display.c:102:37: error: bitwise comparison always evaluates to false [-Werror=tautological-compare]

This changes it to a simple bit mask operation to check
whether the bit is set.

Fixes: 026abc333205 ("gma500: initial medfield merge")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 drivers/gpu/drm/gma500/mdfld_intel_display.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/gma500/mdfld_intel_display.c b/drivers/gpu/drm/gma500/mdfld_intel_display.c
index 531e4450c000..5c066448be5b 100644
--- a/drivers/gpu/drm/gma500/mdfld_intel_display.c
+++ b/drivers/gpu/drm/gma500/mdfld_intel_display.c
@@ -99,7 +99,7 @@ void mdfldWaitForPipeEnable(struct drm_device *dev, int pipe)
 	/* Wait for for the pipe enable to take effect. */
 	for (count = 0; count < COUNT_MAX; count++) {
 		temp = REG_READ(map->conf);
-		if ((temp & PIPEACONF_PIPE_STATE) == 1)
+		if (temp & PIPEACONF_PIPE_STATE)
 			break;
 	}
 }
-- 
2.9.0