Preston_PLB/kernel-aes67
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
4d9391557b
kernel-aes67/sound/arm/pxa2xx-ac97-lib.c
Dmitry Baryshkov 7961233688 pxa2xx-ac97: switch AC unit to correct state before probing 
If AC97 unit is in partially enabled state, early request_irq can trigger
IRQ storm or even full hang up. Workaround this by forcibly switching ACLINK off
at the start of the probe.

Signed-off-by: Dmitry Baryshkov <dbaryshkov@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
2009-01-05 17:47:17 +00:00

392 lines
8.4 KiB
C
Raw Blame History

/*
* Based on sound/arm/pxa2xx-ac97.c and sound/soc/pxa/pxa2xx-ac97.c
* which contain:
*
* Author: Nicolas Pitre
* Created: Dec 02, 2004
* Copyright: MontaVista Software Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/delay.h>
#include <sound/ac97_codec.h>
#include <sound/pxa2xx-lib.h>
#include <asm/irq.h>
#include <mach/hardware.h>
#include <mach/regs-ac97.h>
#include <mach/pxa2xx-gpio.h>
#include <mach/audio.h>
static DEFINE_MUTEX(car_mutex);
static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
static volatile long gsr_bits;
static struct clk *ac97_clk;
static struct clk *ac97conf_clk;
/*
* Beware PXA27x bugs:
*
* o Slot 12 read from modem space will hang controller.
* o CDONE, SDONE interrupt fails after any slot 12 IO.
*
* We therefore have an hybrid approach for waiting on SDONE (interrupt or
* 1 jiffy timeout if interrupt never comes).
*/
unsigned short pxa2xx_ac97_read(struct snd_ac97 *ac97, unsigned short reg)
{
unsigned short val = -1;
volatile u32 *reg_addr;
mutex_lock(&car_mutex);
/* set up primary or secondary codec space */
if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
else
reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
reg_addr += (reg >> 1);
/* start read access across the ac97 link */
GSR = GSR_CDONE | GSR_SDONE;
gsr_bits = 0;
val = *reg_addr;
if (reg == AC97_GPIO_STATUS)
goto out;
if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1) <= 0 &&
!((GSR | gsr_bits) & GSR_SDONE)) {
printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
__func__, reg, GSR | gsr_bits);
val = -1;
goto out;
}
/* valid data now */
GSR = GSR_CDONE | GSR_SDONE;
gsr_bits = 0;
val = *reg_addr;
/* but we've just started another cycle... */
wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_SDONE, 1);
out: mutex_unlock(&car_mutex);
return val;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
void pxa2xx_ac97_write(struct snd_ac97 *ac97, unsigned short reg,
unsigned short val)
{
volatile u32 *reg_addr;
mutex_lock(&car_mutex);
/* set up primary or secondary codec space */
if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
reg_addr = ac97->num ? &SMC_REG_BASE : &PMC_REG_BASE;
else
reg_addr = ac97->num ? &SAC_REG_BASE : &PAC_REG_BASE;
reg_addr += (reg >> 1);
GSR = GSR_CDONE | GSR_SDONE;
gsr_bits = 0;
*reg_addr = val;
if (wait_event_timeout(gsr_wq, (GSR | gsr_bits) & GSR_CDONE, 1) <= 0 &&
!((GSR | gsr_bits) & GSR_CDONE))
printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
__func__, reg, GSR | gsr_bits);
mutex_unlock(&car_mutex);
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
#ifdef CONFIG_PXA25x
static inline void pxa_ac97_warm_pxa25x(void)
{
gsr_bits = 0;
GCR |= GCR_WARM_RST | GCR_PRIRDY_IEN | GCR_SECRDY_IEN;
wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
}
static inline void pxa_ac97_cold_pxa25x(void)
{
GCR &= GCR_COLD_RST; /* clear everything but nCRST */
GCR &= ~GCR_COLD_RST; /* then assert nCRST */
gsr_bits = 0;
GCR = GCR_COLD_RST;
GCR |= GCR_CDONE_IE|GCR_SDONE_IE;
wait_event_timeout(gsr_wq, gsr_bits & (GSR_PCR | GSR_SCR), 1);
}
#endif
#ifdef CONFIG_PXA27x
static inline void pxa_ac97_warm_pxa27x(void)
{
gsr_bits = 0;
/* warm reset broken on Bulverde,
so manually keep AC97 reset high */
pxa_gpio_mode(113 | GPIO_OUT | GPIO_DFLT_HIGH);
udelay(10);
GCR |= GCR_WARM_RST;
pxa_gpio_mode(113 | GPIO_ALT_FN_2_OUT);
udelay(500);
}
static inline void pxa_ac97_cold_pxa27x(void)
{
GCR &= GCR_COLD_RST; /* clear everything but nCRST */
GCR &= ~GCR_COLD_RST; /* then assert nCRST */
gsr_bits = 0;
/* PXA27x Developers Manual section 13.5.2.2.1 */
clk_enable(ac97conf_clk);
udelay(5);
clk_disable(ac97conf_clk);
GCR = GCR_COLD_RST;
udelay(50);
}
#endif
#ifdef CONFIG_PXA3xx
static inline void pxa_ac97_warm_pxa3xx(void)
{
int timeout = 100;
gsr_bits = 0;
/* Can't use interrupts */
GCR |= GCR_WARM_RST;
while (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
mdelay(1);
}
static inline void pxa_ac97_cold_pxa3xx(void)
{
int timeout = 1000;
/* Hold CLKBPB for 100us */
GCR = 0;
GCR = GCR_CLKBPB;
udelay(100);
GCR = 0;
GCR &= GCR_COLD_RST; /* clear everything but nCRST */
GCR &= ~GCR_COLD_RST; /* then assert nCRST */
gsr_bits = 0;
/* Can't use interrupts on PXA3xx */
GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
GCR = GCR_WARM_RST | GCR_COLD_RST;
while (!(GSR & (GSR_PCR | GSR_SCR)) && timeout--)
mdelay(10);
}
#endif
bool pxa2xx_ac97_try_warm_reset(struct snd_ac97 *ac97)
{
#ifdef CONFIG_PXA25x
if (cpu_is_pxa25x())
pxa_ac97_warm_pxa25x();
else
#endif
#ifdef CONFIG_PXA27x
if (cpu_is_pxa27x())
pxa_ac97_warm_pxa27x();
else
#endif
#ifdef CONFIG_PXA3xx
if (cpu_is_pxa3xx())
pxa_ac97_warm_pxa3xx();
else
#endif
BUG();
if (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR))) {
printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
__func__, gsr_bits);
return false;
}
return true;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
bool pxa2xx_ac97_try_cold_reset(struct snd_ac97 *ac97)
{
#ifdef CONFIG_PXA25x
if (cpu_is_pxa25x())
pxa_ac97_cold_pxa25x();
else
#endif
#ifdef CONFIG_PXA27x
if (cpu_is_pxa27x())
pxa_ac97_cold_pxa27x();
else
#endif
#ifdef CONFIG_PXA3xx
if (cpu_is_pxa3xx())
pxa_ac97_cold_pxa3xx();
else
#endif
BUG();
if (!((GSR | gsr_bits) & (GSR_PCR | GSR_SCR))) {
printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
__func__, gsr_bits);
return false;
}
return true;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
void pxa2xx_ac97_finish_reset(struct snd_ac97 *ac97)
{
GCR &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
GCR |= GCR_SDONE_IE|GCR_CDONE_IE;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
{
long status;
status = GSR;
if (status) {
GSR = status;
gsr_bits |= status;
wake_up(&gsr_wq);
/* Although we don't use those we still need to clear them
since they tend to spuriously trigger when MMC is used
(hardware bug? go figure)... */
if (cpu_is_pxa27x()) {
MISR = MISR_EOC;
PISR = PISR_EOC;
MCSR = MCSR_EOC;
}
return IRQ_HANDLED;
}
return IRQ_NONE;
}
#ifdef CONFIG_PM
int pxa2xx_ac97_hw_suspend(void)
{
GCR |= GCR_ACLINK_OFF;
clk_disable(ac97_clk);
return 0;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
int pxa2xx_ac97_hw_resume(void)
{
if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
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);
}
clk_enable(ac97_clk);
return 0;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
#endif
int __devinit pxa2xx_ac97_hw_probe(struct platform_device *dev)
{
int ret;
if (cpu_is_pxa25x() || cpu_is_pxa27x()) {
pxa_gpio_mode(GPIO31_SYNC_AC97_MD);
pxa_gpio_mode(GPIO30_SDATA_OUT_AC97_MD);
pxa_gpio_mode(GPIO28_BITCLK_AC97_MD);
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);
ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
if (IS_ERR(ac97conf_clk)) {
ret = PTR_ERR(ac97conf_clk);
ac97conf_clk = NULL;
goto err_conf;
}
}
ac97_clk = clk_get(&dev->dev, "AC97CLK");
if (IS_ERR(ac97_clk)) {
ret = PTR_ERR(ac97_clk);
ac97_clk = NULL;
goto err_clk;
}
ret = clk_enable(ac97_clk);
if (ret)
goto err_clk2;
ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, IRQF_DISABLED, "AC97", NULL);
if (ret < 0)
goto err_irq;
return 0;
err_irq:
GCR |= GCR_ACLINK_OFF;
err_clk2:
clk_put(ac97_clk);
ac97_clk = NULL;
err_clk:
if (ac97conf_clk) {
clk_put(ac97conf_clk);
ac97conf_clk = NULL;
}
err_conf:
return ret;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
void pxa2xx_ac97_hw_remove(struct platform_device *dev)
{
GCR |= GCR_ACLINK_OFF;
free_irq(IRQ_AC97, NULL);
if (ac97conf_clk) {
clk_put(ac97conf_clk);
ac97conf_clk = NULL;
}
clk_disable(ac97_clk);
clk_put(ac97_clk);
ac97_clk = NULL;
}
EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
MODULE_AUTHOR("Nicolas Pitre");
MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
MODULE_LICENSE("GPL");
Reference in New Issue View Git Blame Copy Permalink