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root/sound/arm/pxa2xx-ac97-lib.c

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DEFINITIONS

This source file includes following definitions.
  1. pxa2xx_ac97_read
  2. pxa2xx_ac97_write
  3. pxa_ac97_warm_pxa25x
  4. pxa_ac97_cold_pxa25x
  5. pxa_ac97_warm_pxa27x
  6. pxa_ac97_cold_pxa27x
  7. pxa_ac97_warm_pxa3xx
  8. pxa_ac97_cold_pxa3xx
  9. pxa2xx_ac97_try_warm_reset
  10. pxa2xx_ac97_try_cold_reset
  11. pxa2xx_ac97_finish_reset
  12. pxa2xx_ac97_irq
  13. pxa2xx_ac97_hw_suspend
  14. pxa2xx_ac97_hw_resume
  15. pxa2xx_ac97_hw_probe
  16. pxa2xx_ac97_hw_remove

/*
 * 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/pxa-regs.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_pxa21x() || 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_pxa21x() || 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_pxa21x() || 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_pxa21x() || 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_pxa21x() || 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;

        ret = request_irq(IRQ_AC97, pxa2xx_ac97_irq, 0, "AC97", NULL);
        if (ret < 0)
                goto err;

        if (cpu_is_pxa21x() || 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_irq;
                }
        }

        ac97_clk = clk_get(&dev->dev, "AC97CLK");
        if (IS_ERR(ac97_clk)) {
                ret = PTR_ERR(ac97_clk);
                ac97_clk = NULL;
                goto err_irq;
        }

        return clk_enable(ac97_clk);

err_irq:
        GCR |= GCR_ACLINK_OFF;
        if (ac97conf_clk) {
                clk_put(ac97conf_clk);
                ac97conf_clk = NULL;
        }
        free_irq(IRQ_AC97, NULL);
err:
        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");


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