[PATCH 3/4] ALSA: pxa27x: ac97 controller driver requests gpio
Igor Grinberg
grinberg at compulab.co.il
Mon Jan 7 04:36:16 EST 2013
On 01/06/13 21:13, Mike Dunn wrote:
> 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;
> + }
I think if we are fine with the request in the driver,
then we should move the direction and value configuration also
to the driver, but let the pxa27x_assert_ac97reset() only switch
the AF.
> 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) {
--
Regards,
Igor.
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