ALSA: hdac_regmap - fix the register access for runtime PM

Call path:

  1) snd_hdac_power_up_pm()
  2) snd_hdac_power_up()
  3) pm_runtime_get_sync()
  4) __pm_runtime_resume()
  5) rpm_resume()

The rpm_resume() returns 1 when the device is already active.
Because the return value is unmodified, the hdac regmap read/write
functions should allow this value for the retry I/O operation, too.
Signed-off-by: NJaroslav Kysela <perex@perex.cz>
Cc: <stable@vger.kernel.org>
Signed-off-by: NTakashi Iwai <tiwai@suse.de>

sound/hda/hdac_regmap.c

@@ -444,7 +444,7 @@ int snd_hdac_regmap_write_raw(struct hdac_device *codec, unsigned int reg,
 	err = reg_raw_write(codec, reg, val);
 	if (err == -EAGAIN) {
 		err = snd_hdac_power_up_pm(codec);
-		if (!err)
+		if (err >= 0)
 			err = reg_raw_write(codec, reg, val);
 		snd_hdac_power_down_pm(codec);
 	}
@@ -470,7 +470,7 @@ static int __snd_hdac_regmap_read_raw(struct hdac_device *codec,
 	err = reg_raw_read(codec, reg, val, uncached);
 	if (err == -EAGAIN) {
 		err = snd_hdac_power_up_pm(codec);
-		if (!err)
+		if (err >= 0)
 			err = reg_raw_read(codec, reg, val, uncached);
 		snd_hdac_power_down_pm(codec);
 	}