ASoC: Allow choice of ac97 gpio reset line

As the PXA27x series allow 2 gpios to reset the ac97 bus,
allow through platform data configuration the definition of
the correct gpio which will reset the AC97 bus.

This comes from a silicon defect on the PXA27x series, where
the gpio must be manually controlled in warm reset cases.

Signed-off-by: Robert Jarzmik <rjarzmik@free.fr>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This commit is contained in:
Robert Jarzmik 2009-03-15 14:10:54 +01:00 committed by Mark Brown
parent 77dd7e17b8
commit 26ade896b6
2 changed files with 81 additions and 5 deletions

View file

@ -42,4 +42,19 @@ extern int pxa2xx_ac97_hw_resume(void);
extern int pxa2xx_ac97_hw_probe(struct platform_device *dev);
extern void pxa2xx_ac97_hw_remove(struct platform_device *dev);
/* AC97 platform_data */
/**
* struct pxa2xx_ac97_platform_data - pxa ac97 platform data
* @reset_gpio: AC97 reset gpio (normally gpio113 or gpio95)
* a -1 value means no gpio will be used for reset
*
* Platform data should only be specified for pxa27x CPUs where a silicon bug
* prevents correct operation of the reset line. If not specified, the default
* behaviour is to consider gpio 113 as the AC97 reset line, which is the
* default on most boards.
*/
struct pxa2xx_ac97_platform_data {
int reset_gpio;
};
#endif

View file

@ -31,6 +31,7 @@ static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
static volatile long gsr_bits;
static struct clk *ac97_clk;
static struct clk *ac97conf_clk;
static int reset_gpio;
/*
* Beware PXA27x bugs:
@ -42,6 +43,45 @@ static struct clk *ac97conf_clk;
* 1 jiffy timeout if interrupt never comes).
*/
enum {
RESETGPIO_FORCE_HIGH,
RESETGPIO_FORCE_LOW,
RESETGPIO_NORMAL_ALTFUNC
};
/**
* set_resetgpio_mode - computes and sets the AC97_RESET gpio mode on PXA
* @mode: chosen action
*
* As the PXA27x CPUs suffer from a AC97 bug, a manual control of the reset line
* must be done to insure proper work of AC97 reset line. This function
* computes the correct gpio_mode for further use by reset functions, and
* applied the change through pxa_gpio_mode.
*/
static void set_resetgpio_mode(int resetgpio_action)
{
int mode = 0;
if (reset_gpio)
switch (resetgpio_action) {
case RESETGPIO_NORMAL_ALTFUNC:
if (reset_gpio == 113)
mode = 113 | GPIO_OUT | GPIO_DFLT_LOW;
if (reset_gpio == 95)
mode = 95 | GPIO_ALT_FN_1_OUT;
break;
case RESETGPIO_FORCE_LOW:
mode = reset_gpio | GPIO_OUT | GPIO_DFLT_LOW;
break;
case RESETGPIO_FORCE_HIGH:
mode = reset_gpio | GPIO_OUT | GPIO_DFLT_HIGH;
break;
};
if (mode)
pxa_gpio_mode(mode);
}
unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
{
unsigned short val = -1;
@ -137,10 +177,10 @@ static inline void pxa_ac97_warm_pxa27x(void)
/* warm reset broken on Bulverde,
so manually keep AC97 reset high */
pxa_gpio_mode(113 | GPIO_OUT | GPIO_DFLT_HIGH);
set_resetgpio_mode(RESETGPIO_FORCE_HIGH);
udelay(10);
GCR |= GCR_WARM_RST;
pxa_gpio_mode(113 | GPIO_ALT_FN_2_OUT);
set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
udelay(500);
}
@ -308,8 +348,8 @@ int pxa2xx_ac97_hw_resume(void)
pxa_gpio_mode(GPIO29_SDATA_IN_AC97_MD);
}
if (cpu_is_pxa27x()) {
/* Use GPIO 113 as AC97 Reset on Bulverde */
pxa_gpio_mode(113 | GPIO_ALT_FN_2_OUT);
/* Use GPIO 113 or 95 as AC97 Reset on Bulverde */
set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
}
clk_enable(ac97_clk);
return 0;
@ -320,6 +360,27 @@ EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
{
int ret;
struct pxa2xx_ac97_platform_data *pdata = dev->dev.platform_data;
if (pdata) {
switch (pdata->reset_gpio) {
case 95:
case 113:
reset_gpio = pdata->reset_gpio;
break;
case 0:
reset_gpio = 113;
break;
case -1:
break;
default:
dev_err(dev, "Invalid reset GPIO %d\n",
pdata->reset_gpio);
}
} else {
if (cpu_is_pxa27x())
reset_gpio = 113;
}
if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
@ -330,7 +391,7 @@ int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
if (cpu_is_pxa27x()) {
/* Use GPIO 113 as AC97 Reset on Bulverde */
pxa_gpio_mode(113 | GPIO_ALT_FN_2_OUT);
set_resetgpio_mode(RESETGPIO_NORMAL_ALTFUNC);
ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
if (IS_ERR(ac97conf_clk)) {
ret = PTR_ERR(ac97conf_clk);