ALSA: snd-atmel-ac97c: do a proper reset of the external codec

This patch will enable the AC97C before resetting the external codec,
leaving the AC97C disabled will result in floating I/O lines that can
affect the reset procedure.

Signed-off-by: Hans-Christian Egtvedt <hans-christian.egtvedt@atmel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

diff --git a/sound/atmel/ac97c.c b/sound/atmel/ac97c.c
index e8484cb..90527c1 100644 (file)
--- a/sound/atmel/ac97c.c
+++ b/sound/atmel/ac97c.c
@@ -730,17 +730,17 @@ static bool filter(struct dma_chan *chan, void *slave)
 
 static void atmel_ac97c_reset(struct atmel_ac97c *chip)
 {
-       ac97c_writel(chip, MR, AC97C_MR_WRST);
+       ac97c_writel(chip, MR,   0);
+       ac97c_writel(chip, MR,   AC97C_MR_ENA);
+       ac97c_writel(chip, CAMR, 0);
+       ac97c_writel(chip, COMR, 0);
 
        if (gpio_is_valid(chip->reset_pin)) {
                gpio_set_value(chip->reset_pin, 0);
                /* AC97 v2.2 specifications says minimum 1 us. */
-               udelay(10);
+               udelay(2);
                gpio_set_value(chip->reset_pin, 1);
        }
-
-       udelay(1);
-       ac97c_writel(chip, MR, AC97C_MR_ENA);
 }
 
 static int __devinit atmel_ac97c_probe(struct platform_device *pdev)
@@ -826,6 +826,8 @@ static int __devinit atmel_ac97c_probe(struct platform_device *pdev)
 
        snd_card_set_dev(card, &pdev->dev);
 
+       atmel_ac97c_reset(chip);
+
        /* Enable overrun interrupt from codec channel */
        ac97c_writel(chip, COMR, AC97C_CSR_OVRUN);
        ac97c_writel(chip, IER, ac97c_readl(chip, IMR) | AC97C_SR_COEVT);
@@ -836,8 +838,6 @@ static int __devinit atmel_ac97c_probe(struct platform_device *pdev)
                goto err_ac97_bus;
        }
 
-       atmel_ac97c_reset(chip);
-
        retval = atmel_ac97c_mixer_new(chip);
        if (retval) {
                dev_dbg(&pdev->dev, "could not register ac97 mixer\n");