[alsa-devel] [PATCH 3/4] ALSA: pxa27x: ac97 controller driver requests gpio

Mike Dunn mikedunn at newsguy.com
Sun Jan 6 20:13:59 CET 2013


During initialization, the ac97 driver must obtain the gpio for the mfp that is
used by the ac97 controller as the AC97_nRESET line, or else gpiolib will issue
a warning and stack dump.  Gpiolib may change this to a hard error soon.  The
line is used during an ac97 warm reset for working around a hardware bug in the
controller.

Tested on a palm treo 680 machine.

Signed-off-by: Mike Dunn <mikedunn at newsguy.com>
---
 sound/arm/pxa2xx-ac97-lib.c |   10 +++++++++-
 1 files changed, 9 insertions(+), 1 deletions(-)

diff --git a/sound/arm/pxa2xx-ac97-lib.c b/sound/arm/pxa2xx-ac97-lib.c
index 1ecd0a66..416d2e3 100644
--- a/sound/arm/pxa2xx-ac97-lib.c
+++ b/sound/arm/pxa2xx-ac97-lib.c
@@ -18,6 +18,7 @@
 #include <linux/delay.h>
 #include <linux/module.h>
 #include <linux/io.h>
+#include <linux/gpio.h>
 
 #include <sound/ac97_codec.h>
 #include <sound/pxa2xx-lib.h>
@@ -344,7 +345,12 @@ int pxa2xx_ac97_hw_probe(struct platform_device *dev)
 	}
 
 	if (cpu_is_pxa27x()) {
-		/* Use GPIO 113 as AC97 Reset on Bulverde */
+		ret = gpio_request(reset_gpio, "pxa27x ac97 reset");
+		if (ret < 0) {
+			pr_err("%s: gpio_request() 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)) {
@@ -388,6 +394,8 @@ 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) {
-- 
1.7.8.6



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