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 --- include/sound/pxa2xx-lib.h | 15 +++++++++ sound/arm/pxa2xx-ac97-lib.c | 71 ++++++++++++++++++++++++++++++++++++++++--- 2 files changed, 81 insertions(+), 5 deletions(-)
diff --git a/include/sound/pxa2xx-lib.h b/include/sound/pxa2xx-lib.h index 2fd3d25..2c894b6 100644 --- a/include/sound/pxa2xx-lib.h +++ b/include/sound/pxa2xx-lib.h @@ -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 diff --git a/sound/arm/pxa2xx-ac97-lib.c b/sound/arm/pxa2xx-ac97-lib.c index 35afd0c..d721ea7 100644 --- a/sound/arm/pxa2xx-ac97-lib.c +++ b/sound/arm/pxa2xx-ac97-lib.c @@ -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);