ALSA: pxa27x: fix ac97 warm reset

[pandora-kernel.git] / sound / arm / pxa2xx-ac97-lib.c

diff --git a/sound/arm/pxa2xx-ac97-lib.c b/sound/arm/pxa2xx-ac97-lib.c
index 9ba64d5..52a4318 100644 (file)
--- a/sound/arm/pxa2xx-ac97-lib.c
+++ b/sound/arm/pxa2xx-ac97-lib.c
@@ -17,6 +17,7 @@
 #include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/module.h>
+#include <linux/gpio.h>
 
 #include <sound/ac97_codec.h>
 #include <sound/pxa2xx-lib.h>
@@ -343,8 +344,21 @@ int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
        }
 
        if (cpu_is_pxa27x()) {
-               /* Use GPIO 113 as AC97 Reset on Bulverde */
+               /*
+                * This gpio is needed for a work-around to a bug in the ac97
+                * controller during warm reset.  The direction and level is set
+                * here so that it is an output driven high when switching from
+                * AC97_nRESET alt function to generic gpio.
+                */
+               ret = gpio_request_one(reset_gpio, GPIOF_OUT_INIT_HIGH,
+                                      "pxa27x ac97 reset");
+               if (ret < 0) {
+                       pr_err("%s: gpio_request_one() failed: %d\n",
+                              __func__, ret);
+                       goto err_conf;
+               }
                pxa27x_assert_ac97reset(reset_gpio, 0);
+
                ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
                if (IS_ERR(ac97conf_clk)) {
                        ret = PTR_ERR(ac97conf_clk);
@@ -387,6 +401,8 @@ EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
 
 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
 {
+       if (cpu_is_pxa27x())
+               gpio_free(reset_gpio);
        GCR |= GCR_ACLINK_OFF;
        free_irq(IRQ_AC97, NULL);
        if (ac97conf_clk) {