ALSA: cs4236: detect chip in one pass

The cs4236 was two step detection with call to the snd_wss_free()
between two steps. The snd_wss_free() did not free a sound device
created in the snd_wss_create(). This caused an OOPS during module
removal as the same sound device was released twice. The same OOPS
happened if the cs4236 module loading failed.

Fix this by adapting the snd_cs4236_create() to correctly work with
chips less capable then cs4236. The snd_cs4236_create() behaves the
same as the snd_wss_create() if the chip is less capable than the cs4236.

Signed-off-by: Krzysztof Helt <[e-mail]>
Signed-off-by: Takashi Iwai <[e-mail]>

include/sound/wss.h

···
 		      unsigned short hardware,
 		      unsigned short hwshare,
 		      struct snd_wss **rchip);
-int snd_wss_free(struct snd_wss *chip);
 int snd_wss_pcm(struct snd_wss *chip, int device, struct snd_pcm **rpcm);
 int snd_wss_timer(struct snd_wss *chip, int device, struct snd_timer **rtimer);
 int snd_wss_mixer(struct snd_wss *chip);

sound/isa/cs423x/cs4236.c

···
 			return -EBUSY;
 		}
 
-	err = snd_wss_create(card, port[dev], cport[dev],
+	err = snd_cs4236_create(card, port[dev], cport[dev],
 			     irq[dev],
 			     dma1[dev], dma2[dev],
 			     WSS_HW_DETECT3, 0, &chip);
 	if (err < 0)
 		return err;
+
+	acard->chip = chip;
 	if (chip->hardware & WSS_HW_CS4236B_MASK) {
-		snd_wss_free(chip);
-		err = snd_cs4236_create(card,
-					port[dev], cport[dev],
-					irq[dev], dma1[dev], dma2[dev],
-					WSS_HW_DETECT, 0, &chip);
-		if (err < 0)
-			return err;
-		acard->chip = chip;
 
 		err = snd_cs4236_pcm(chip, 0, &pcm);
 		if (err < 0)
···
 		if (err < 0)
 			return err;
 	} else {
-		acard->chip = chip;
 		err = snd_wss_pcm(chip, 0, &pcm);
 		if (err < 0)
 			return err;

sound/isa/cs423x/cs4236_lib.c

···
 #include <sound/core.h>
 #include <sound/wss.h>
 #include <sound/asoundef.h>
+#include <sound/initval.h>
 
 /*
  *
···
 }
 
 #endif /* CONFIG_PM */
-
+/*
+ * This function does no fail if the chip is not CS4236B or compatible.
+ * It just an equivalent to the snd_wss_create() then.
+ */
 int snd_cs4236_create(struct snd_card *card,
 		      unsigned long port,
 		      unsigned long cport,
···
 	*rchip = NULL;
 	if (hardware == WSS_HW_DETECT)
 		hardware = WSS_HW_DETECT3;
-	if (cport < 0x100) {
-		snd_printk(KERN_ERR "please, specify control port "
-			   "for CS4236+ chips\n");
-		return -ENODEV;
-	}
+
 	err = snd_wss_create(card, port, cport,
 			     irq, dma1, dma2, hardware, hwshare, &chip);
 	if (err < 0)
 		return err;
 
-	if (!(chip->hardware & WSS_HW_CS4236B_MASK)) {
-		snd_printk(KERN_ERR "CS4236+: MODE3 and extended registers "
-			   "not available, hardware=0x%x\n", chip->hardware);
-		snd_device_free(card, chip);
-		return -ENODEV;
+	if ((chip->hardware & WSS_HW_CS4236B_MASK) == 0) {
+		snd_printd("chip is not CS4236+, hardware=0x%x\n",
+			   chip->hardware);
+		*rchip = chip;
+		return 0;
 	}
 #if 0
 	{
···
 				   idx, snd_cs4236_ctrl_in(chip, idx));
 	}
 #endif
+	if (cport < 0x100 || cport == SNDRV_AUTO_PORT) {
+		snd_printk(KERN_ERR "please, specify control port "
+			   "for CS4236+ chips\n");
+		snd_device_free(card, chip);
+		return -ENODEV;
+	}
 	ver1 = snd_cs4236_ctrl_in(chip, 1);
 	ver2 = snd_cs4236_ext_in(chip, CS4236_VERSION);
-	snd_printdd("CS4236: [0x%lx] C1 (version) = 0x%x, ext = 0x%x\n", cport, ver1, ver2);
+	snd_printdd("CS4236: [0x%lx] C1 (version) = 0x%x, ext = 0x%x\n",
+			cport, ver1, ver2);
 	if (ver1 != ver2) {
 		snd_printk(KERN_ERR "CS4236+ chip detected, but "
 			   "control port 0x%lx is not valid\n", cport);
···
 	snd_cs4236_ctrl_out(chip, 2, 0xff);
 	snd_cs4236_ctrl_out(chip, 3, 0x00);
 	snd_cs4236_ctrl_out(chip, 4, 0x80);
-	snd_cs4236_ctrl_out(chip, 5, ((IEC958_AES1_CON_PCM_CODER & 3) << 6) | IEC958_AES0_CON_EMPHASIS_NONE);
+	reg = ((IEC958_AES1_CON_PCM_CODER & 3) << 6) |
+	      IEC958_AES0_CON_EMPHASIS_NONE;
+	snd_cs4236_ctrl_out(chip, 5, reg);
 	snd_cs4236_ctrl_out(chip, 6, IEC958_AES1_CON_PCM_CODER >> 2);
 	snd_cs4236_ctrl_out(chip, 7, 0x00);
-	/* 0x8c for C8 is valid for Turtle Beach Malibu - the IEC-958 output */
-	/* is working with this setup, other hardware should have */
-	/* different signal paths and this value should be selectable */
-	/* in the future */
+	/*
+	 * 0x8c for C8 is valid for Turtle Beach Malibu - the IEC-958
+	 * output is working with this setup, other hardware should
+	 * have different signal paths and this value should be
+	 * selectable in the future
+	 */
 	snd_cs4236_ctrl_out(chip, 8, 0x8c);
 	chip->rate_constraint = snd_cs4236_xrate;
 	chip->set_playback_format = snd_cs4236_playback_format;
···
 
 	/* initialize extended registers */
 	for (reg = 0; reg < sizeof(snd_cs4236_ext_map); reg++)
-		snd_cs4236_ext_out(chip, CS4236_I23VAL(reg), snd_cs4236_ext_map[reg]);
+		snd_cs4236_ext_out(chip, CS4236_I23VAL(reg),
+				   snd_cs4236_ext_map[reg]);
 
-        /* initialize compatible but more featured registers */
+	/* initialize compatible but more featured registers */
 	snd_wss_out(chip, CS4231_LEFT_INPUT, 0x40);
 	snd_wss_out(chip, CS4231_RIGHT_INPUT, 0x40);
 	snd_wss_out(chip, CS4231_AUX1_LEFT_INPUT, 0xff);

sound/isa/wss/wss_lib.c

···
 }
 #endif /* CONFIG_PM */
 
-int snd_wss_free(struct snd_wss *chip)
+static int snd_wss_free(struct snd_wss *chip)
 {
 	release_and_free_resource(chip->res_port);
 	release_and_free_resource(chip->res_cport);
···
 	kfree(chip);
 	return 0;
 }
-EXPORT_SYMBOL(snd_wss_free);
 
 static int snd_wss_dev_free(struct snd_device *device)
 {