[ALSA] cs4281 - fix DLLRDY not seen problem

CS4281 driver
Reset the FPDN bit of the EPPMC register if needed.

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

1 files changed, 8 insertions, 0 deletions

diff --git a/sound/pci/cs4281.c b/sound/pci/cs4281.c
index 8b42e8631f2a..b6e1854e9389 100644
--- a/sound/pci/cs4281.c
+++ b/sound/pci/cs4281.c
@@ -206,7 +206,10 @@ MODULE_PARM_DESC(dual_codec, "Secondary Codec ID (0 = disabled).");
 
 #define BA0_PMCS                0x0344  /* Power Management Control/Status */
 #define BA0_CWPR                0x03e0  /* Configuration Write Protect */
+
 #define BA0_EPPMC               0x03e4  /* Extended PCI Power Management Control */
+#define BA0_EPPMC_FPDN          (1<<14) /* Full Power DowN */
+
 #define BA0_GPIOR               0x03e8  /* GPIO Pin Interface Register */
 
 #define BA0_SPMC                0x03ec  /* Serial Port Power Management Control (& ASDIN2 enable) */
@@ -1461,6 +1464,11 @@ static int snd_cs4281_chip_init(cs4281_t *chip)
         int timeout;
         int retry_count = 2;
 
+        /* Having EPPMC.FPDN=1 prevent proper chip initialisation */
+        tmp = snd_cs4281_peekBA0(chip, BA0_EPPMC);
+        if (tmp & BA0_EPPMC_FPDN)
+                snd_cs4281_pokeBA0(chip, BA0_EPPMC, tmp & ~BA0_EPPMC_FPDN);
+
       __retry:
         tmp = snd_cs4281_peekBA0(chip, BA0_CFLR);
         if (tmp != BA0_CFLR_DEFAULT) {