linux-imx

/*

 *  Driver for PC-speaker like devices found on various Sparc systems.

 *

 *  Copyright (c) 2002 Vojtech Pavlik

 *  Copyright (c) 2002, 2006, 2008 David S. Miller (davem@davemloft.net)

 */

#include <linux/kernel.h>

#include <linux/module.h>

#include <linux/init.h>

#include <linux/input.h>

#include <linux/of_device.h>

#include <linux/slab.h>

​

#include <asm/io.h>

​

MODULE_AUTHOR("David S. Miller <davem@davemloft.net>");

MODULE_DESCRIPTION("Sparc Speaker beeper driver");

MODULE_LICENSE("GPL");

​

struct grover_beep_info {

    void __iomem    *freq_regs;

    void __iomem    *enable_reg;

};

​

struct bbc_beep_info {

    u32     clock_freq;

    void __iomem    *regs;

};

​

struct sparcspkr_state {

    const char      *name;

    int (*event)(struct input_dev *dev, unsigned int type, unsigned int code, int value);

    spinlock_t      lock;

    struct input_dev    *input_dev;

    union {

        struct grover_beep_info grover;

        struct bbc_beep_info bbc;

    } u;

};

​

static u32 bbc_count_to_reg(struct bbc_beep_info *info, unsigned int count)

{

    u32 val, clock_freq = info->clock_freq;

    int i;

​

    if (!count)

        return 0;

​

    if (count <= clock_freq >> 20)

        return 1 << 18;

​

    if (count >= clock_freq >> 12)

        return 1 << 10;

​

    val = 1 << 18;

    for (i = 19; i >= 11; i--) {

        val >>= 1;

        if (count <= clock_freq >> i)

            break;

    }

​

    return val;

}

​

static int bbc_spkr_event(struct input_dev *dev, unsigned int type, unsigned int code, int value)

{

    struct sparcspkr_state *state = dev_get_drvdata(dev->dev.parent);

    struct bbc_beep_info *info = &state->u.bbc;

    unsigned int count = 0;

    unsigned long flags;

​

    if (type != EV_SND)

        return -1;

​

    switch (code) {

        case SND_BELL: if (value) value = 1000;

        case SND_TONE: break;

        default: return -1;

    }

​

    if (value > 20 && value < 32767)

        count = 1193182 / value;

​

    count = bbc_count_to_reg(info, count);

​

    spin_lock_irqsave(&state->lock, flags);

​

    if (count) {

        sbus_writeb(0x01,                 info->regs + 0);

        sbus_writeb(0x00,                 info->regs + 2);

        sbus_writeb((count >> 16) & 0xff, info->regs + 3);

        sbus_writeb((count >>  8) & 0xff, info->regs + 4);