nilfs2: fix oopses with doubly mounted snapshots

[linux-2.6/mini2440.git] / arch / arm / common / sa1111.c

/*
 * linux/arch/arm/common/sa1111.c
 *
 * SA1111 support
 *
 * Original code by John Dorsey
 *
 * 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.
 *
 * This file contains all generic SA1111 support.
 *
 * All initialization functions provided here are intended to be called
 * from machine specific code with proper arguments when required.
 */
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/dma-mapping.h>
#include <linux/clk.h>
#include <linux/io.h>

#include <mach/hardware.h>
#include <asm/mach-types.h>
#include <asm/irq.h>
#include <asm/mach/irq.h>
#include <asm/sizes.h>

#include <asm/hardware/sa1111.h>

extern void __init sa1110_mb_enable(void);

/*
 * We keep the following data for the overall SA1111.  Note that the
 * struct device and struct resource are "fake"; they should be supplied
 * by the bus above us.  However, in the interests of getting all SA1111
 * drivers converted over to the device model, we provide this as an
 * anchor point for all the other drivers.
 */
struct sa1111 {
        struct device   *dev;
        struct clk      *clk;
        unsigned long   phys;
        int             irq;
        spinlock_t      lock;
        void __iomem    *base;
#ifdef CONFIG_PM
        void            *saved_state;
#endif
};

/*
 * We _really_ need to eliminate this.  Its only users
 * are the PWM and DMA checking code.
 */
static struct sa1111 *g_sa1111;

struct sa1111_dev_info {
        unsigned long   offset;
        unsigned long   skpcr_mask;
        unsigned int    devid;
        unsigned int    irq[6];
};

static struct sa1111_dev_info sa1111_devices[] = {
        {
                .offset         = SA1111_USB,
                .skpcr_mask     = SKPCR_UCLKEN,
                .devid          = SA1111_DEVID_USB,
                .irq = {
                        IRQ_USBPWR,
                        IRQ_HCIM,
                        IRQ_HCIBUFFACC,
                        IRQ_HCIRMTWKP,
                        IRQ_NHCIMFCIR,
                        IRQ_USB_PORT_RESUME
                },
        },
        {
                .offset         = 0x0600,
                .skpcr_mask     = SKPCR_I2SCLKEN | SKPCR_L3CLKEN,
                .devid          = SA1111_DEVID_SAC,
                .irq = {
                        AUDXMTDMADONEA,
                        AUDXMTDMADONEB,
                        AUDRCVDMADONEA,
                        AUDRCVDMADONEB
                },
        },
        {
                .offset         = 0x0800,
                .skpcr_mask     = SKPCR_SCLKEN,
                .devid          = SA1111_DEVID_SSP,
        },
        {
                .offset         = SA1111_KBD,
                .skpcr_mask     = SKPCR_PTCLKEN,
                .devid          = SA1111_DEVID_PS2,
                .irq = {
                        IRQ_TPRXINT,
                        IRQ_TPTXINT
                },
        },
        {
                .offset         = SA1111_MSE,
                .skpcr_mask     = SKPCR_PMCLKEN,
                .devid          = SA1111_DEVID_PS2,
                .irq = {
                        IRQ_MSRXINT,
                        IRQ_MSTXINT
                },
        },
        {
                .offset         = 0x1800,
                .skpcr_mask     = 0,
                .devid          = SA1111_DEVID_PCMCIA,
                .irq = {
                        IRQ_S0_READY_NINT,
                        IRQ_S0_CD_VALID,
                        IRQ_S0_BVD1_STSCHG,
                        IRQ_S1_READY_NINT,
                        IRQ_S1_CD_VALID,
                        IRQ_S1_BVD1_STSCHG,
                },
        },
};

void __init sa1111_adjust_zones(int node, unsigned long *size, unsigned long *holes)
{
        unsigned int sz = SZ_1M >> PAGE_SHIFT;

        if (node != 0)
                sz = 0;

        size[1] = size[0] - sz;
        size[0] = sz;
}

/*
 * SA1111 interrupt support.  Since clearing an IRQ while there are
 * active IRQs causes the interrupt output to pulse, the upper levels
 * will call us again if there are more interrupts to process.
 */
static void
sa1111_irq_handler(unsigned int irq, struct irq_desc *desc)
{
        unsigned int stat0, stat1, i;
        void __iomem *base = get_irq_data(irq);

        stat0 = sa1111_readl(base + SA1111_INTSTATCLR0);
        stat1 = sa1111_readl(base + SA1111_INTSTATCLR1);

        sa1111_writel(stat0, base + SA1111_INTSTATCLR0);

        desc->chip->ack(irq);

        sa1111_writel(stat1, base + SA1111_INTSTATCLR1);

        if (stat0 == 0 && stat1 == 0) {
                do_bad_IRQ(irq, desc);
                return;
        }

        for (i = IRQ_SA1111_START; stat0; i++, stat0 >>= 1)
                if (stat0 & 1)
                        handle_edge_irq(i, irq_desc + i);

        for (i = IRQ_SA1111_START + 32; stat1; i++, stat1 >>= 1)
                if (stat1 & 1)
                        handle_edge_irq(i, irq_desc + i);

        /* For level-based interrupts */
        desc->chip->unmask(irq);
}

#define SA1111_IRQMASK_LO(x)    (1 << (x - IRQ_SA1111_START))
#define SA1111_IRQMASK_HI(x)    (1 << (x - IRQ_SA1111_START - 32))

static void sa1111_ack_irq(unsigned int irq)
{
}

static void sa1111_mask_lowirq(unsigned int irq)
{
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ie0;

        ie0 = sa1111_readl(mapbase + SA1111_INTEN0);
        ie0 &= ~SA1111_IRQMASK_LO(irq);
        writel(ie0, mapbase + SA1111_INTEN0);
}

static void sa1111_unmask_lowirq(unsigned int irq)
{
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ie0;

        ie0 = sa1111_readl(mapbase + SA1111_INTEN0);
        ie0 |= SA1111_IRQMASK_LO(irq);
        sa1111_writel(ie0, mapbase + SA1111_INTEN0);
}

/*
 * Attempt to re-trigger the interrupt.  The SA1111 contains a register
 * (INTSET) which claims to do this.  However, in practice no amount of
 * manipulation of INTEN and INTSET guarantees that the interrupt will
 * be triggered.  In fact, its very difficult, if not impossible to get
 * INTSET to re-trigger the interrupt.
 */
static int sa1111_retrigger_lowirq(unsigned int irq)
{
        unsigned int mask = SA1111_IRQMASK_LO(irq);
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ip0;
        int i;

        ip0 = sa1111_readl(mapbase + SA1111_INTPOL0);
        for (i = 0; i < 8; i++) {
                sa1111_writel(ip0 ^ mask, mapbase + SA1111_INTPOL0);
                sa1111_writel(ip0, mapbase + SA1111_INTPOL0);
                if (sa1111_readl(mapbase + SA1111_INTSTATCLR1) & mask)
                        break;
        }

        if (i == 8)
                printk(KERN_ERR "Danger Will Robinson: failed to "
                        "re-trigger IRQ%d\n", irq);
        return i == 8 ? -1 : 0;
}

static int sa1111_type_lowirq(unsigned int irq, unsigned int flags)
{
        unsigned int mask = SA1111_IRQMASK_LO(irq);
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ip0;

        if (flags == IRQ_TYPE_PROBE)
                return 0;

        if ((!(flags & IRQ_TYPE_EDGE_RISING) ^ !(flags & IRQ_TYPE_EDGE_FALLING)) == 0)
                return -EINVAL;

        ip0 = sa1111_readl(mapbase + SA1111_INTPOL0);
        if (flags & IRQ_TYPE_EDGE_RISING)
                ip0 &= ~mask;
        else
                ip0 |= mask;
        sa1111_writel(ip0, mapbase + SA1111_INTPOL0);
        sa1111_writel(ip0, mapbase + SA1111_WAKEPOL0);

        return 0;
}

static int sa1111_wake_lowirq(unsigned int irq, unsigned int on)
{
        unsigned int mask = SA1111_IRQMASK_LO(irq);
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long we0;

        we0 = sa1111_readl(mapbase + SA1111_WAKEEN0);
        if (on)
                we0 |= mask;
        else
                we0 &= ~mask;
        sa1111_writel(we0, mapbase + SA1111_WAKEEN0);

        return 0;
}

static struct irq_chip sa1111_low_chip = {
        .name           = "SA1111-l",
        .ack            = sa1111_ack_irq,
        .mask           = sa1111_mask_lowirq,
        .unmask         = sa1111_unmask_lowirq,
        .retrigger      = sa1111_retrigger_lowirq,
        .set_type       = sa1111_type_lowirq,
        .set_wake       = sa1111_wake_lowirq,
};

static void sa1111_mask_highirq(unsigned int irq)
{
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ie1;

        ie1 = sa1111_readl(mapbase + SA1111_INTEN1);
        ie1 &= ~SA1111_IRQMASK_HI(irq);
        sa1111_writel(ie1, mapbase + SA1111_INTEN1);
}

static void sa1111_unmask_highirq(unsigned int irq)
{
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ie1;

        ie1 = sa1111_readl(mapbase + SA1111_INTEN1);
        ie1 |= SA1111_IRQMASK_HI(irq);
        sa1111_writel(ie1, mapbase + SA1111_INTEN1);
}

/*
 * Attempt to re-trigger the interrupt.  The SA1111 contains a register
 * (INTSET) which claims to do this.  However, in practice no amount of
 * manipulation of INTEN and INTSET guarantees that the interrupt will
 * be triggered.  In fact, its very difficult, if not impossible to get
 * INTSET to re-trigger the interrupt.
 */
static int sa1111_retrigger_highirq(unsigned int irq)
{
        unsigned int mask = SA1111_IRQMASK_HI(irq);
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ip1;
        int i;

        ip1 = sa1111_readl(mapbase + SA1111_INTPOL1);
        for (i = 0; i < 8; i++) {
                sa1111_writel(ip1 ^ mask, mapbase + SA1111_INTPOL1);
                sa1111_writel(ip1, mapbase + SA1111_INTPOL1);
                if (sa1111_readl(mapbase + SA1111_INTSTATCLR1) & mask)
                        break;
        }

        if (i == 8)
                printk(KERN_ERR "Danger Will Robinson: failed to "
                        "re-trigger IRQ%d\n", irq);
        return i == 8 ? -1 : 0;
}

static int sa1111_type_highirq(unsigned int irq, unsigned int flags)
{
        unsigned int mask = SA1111_IRQMASK_HI(irq);
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long ip1;

        if (flags == IRQ_TYPE_PROBE)
                return 0;

        if ((!(flags & IRQ_TYPE_EDGE_RISING) ^ !(flags & IRQ_TYPE_EDGE_FALLING)) == 0)
                return -EINVAL;

        ip1 = sa1111_readl(mapbase + SA1111_INTPOL1);
        if (flags & IRQ_TYPE_EDGE_RISING)
                ip1 &= ~mask;
        else
                ip1 |= mask;
        sa1111_writel(ip1, mapbase + SA1111_INTPOL1);
        sa1111_writel(ip1, mapbase + SA1111_WAKEPOL1);

        return 0;
}

static int sa1111_wake_highirq(unsigned int irq, unsigned int on)
{
        unsigned int mask = SA1111_IRQMASK_HI(irq);
        void __iomem *mapbase = get_irq_chip_data(irq);
        unsigned long we1;

        we1 = sa1111_readl(mapbase + SA1111_WAKEEN1);
        if (on)
                we1 |= mask;
        else
                we1 &= ~mask;
        sa1111_writel(we1, mapbase + SA1111_WAKEEN1);

        return 0;
}

static struct irq_chip sa1111_high_chip = {
        .name           = "SA1111-h",
        .ack            = sa1111_ack_irq,
        .mask           = sa1111_mask_highirq,
        .unmask         = sa1111_unmask_highirq,
        .retrigger      = sa1111_retrigger_highirq,
        .set_type       = sa1111_type_highirq,
        .set_wake       = sa1111_wake_highirq,
};

static void sa1111_setup_irq(struct sa1111 *sachip)
{
        void __iomem *irqbase = sachip->base + SA1111_INTC;
        unsigned int irq;

        /*
         * We're guaranteed that this region hasn't been taken.
         */
        request_mem_region(sachip->phys + SA1111_INTC, 512, "irq");

        /* disable all IRQs */
        sa1111_writel(0, irqbase + SA1111_INTEN0);
        sa1111_writel(0, irqbase + SA1111_INTEN1);
        sa1111_writel(0, irqbase + SA1111_WAKEEN0);
        sa1111_writel(0, irqbase + SA1111_WAKEEN1);

        /*
         * detect on rising edge.  Note: Feb 2001 Errata for SA1111
         * specifies that S0ReadyInt and S1ReadyInt should be '1'.
         */
        sa1111_writel(0, irqbase + SA1111_INTPOL0);
        sa1111_writel(SA1111_IRQMASK_HI(IRQ_S0_READY_NINT) |
                      SA1111_IRQMASK_HI(IRQ_S1_READY_NINT),
                      irqbase + SA1111_INTPOL1);

        /* clear all IRQs */
        sa1111_writel(~0, irqbase + SA1111_INTSTATCLR0);
        sa1111_writel(~0, irqbase + SA1111_INTSTATCLR1);

        for (irq = IRQ_GPAIN0; irq <= SSPROR; irq++) {
                set_irq_chip(irq, &sa1111_low_chip);
                set_irq_chip_data(irq, irqbase);
                set_irq_handler(irq, handle_edge_irq);
                set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
        }

        for (irq = AUDXMTDMADONEA; irq <= IRQ_S1_BVD1_STSCHG; irq++) {
                set_irq_chip(irq, &sa1111_high_chip);
                set_irq_chip_data(irq, irqbase);
                set_irq_handler(irq, handle_edge_irq);
                set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
        }

        /*
         * Register SA1111 interrupt
         */
        set_irq_type(sachip->irq, IRQ_TYPE_EDGE_RISING);
        set_irq_data(sachip->irq, irqbase);
        set_irq_chained_handler(sachip->irq, sa1111_irq_handler);
}

/*
 * Bring the SA1111 out of reset.  This requires a set procedure:
 *  1. nRESET asserted (by hardware)
 *  2. CLK turned on from SA1110
 *  3. nRESET deasserted
 *  4. VCO turned on, PLL_BYPASS turned off
 *  5. Wait lock time, then assert RCLKEn
 *  7. PCR set to allow clocking of individual functions
 *
 * Until we've done this, the only registers we can access are:
 *   SBI_SKCR
 *   SBI_SMCR
 *   SBI_SKID
 */
static void sa1111_wake(struct sa1111 *sachip)
{
        unsigned long flags, r;

        spin_lock_irqsave(&sachip->lock, flags);

        clk_enable(sachip->clk);

        /*
         * Turn VCO on, and disable PLL Bypass.
         */
        r = sa1111_readl(sachip->base + SA1111_SKCR);
        r &= ~SKCR_VCO_OFF;
        sa1111_writel(r, sachip->base + SA1111_SKCR);
        r |= SKCR_PLL_BYPASS | SKCR_OE_EN;
        sa1111_writel(r, sachip->base + SA1111_SKCR);

        /*
         * Wait lock time.  SA1111 manual _doesn't_
         * specify a figure for this!  We choose 100us.
         */
        udelay(100);

        /*
         * Enable RCLK.  We also ensure that RDYEN is set.
         */
        r |= SKCR_RCLKEN | SKCR_RDYEN;
        sa1111_writel(r, sachip->base + SA1111_SKCR);

        /*
         * Wait 14 RCLK cycles for the chip to finish coming out
         * of reset. (RCLK=24MHz).  This is 590ns.
         */
        udelay(1);

        /*
         * Ensure all clocks are initially off.
         */
        sa1111_writel(0, sachip->base + SA1111_SKPCR);

        spin_unlock_irqrestore(&sachip->lock, flags);
}

#ifdef CONFIG_ARCH_SA1100

static u32 sa1111_dma_mask[] = {
        ~0,
        ~(1 << 20),
        ~(1 << 23),
        ~(1 << 24),
        ~(1 << 25),
        ~(1 << 20),
        ~(1 << 20),
        0,
};

/*
 * Configure the SA1111 shared memory controller.
 */
void
sa1111_configure_smc(struct sa1111 *sachip, int sdram, unsigned int drac,
                     unsigned int cas_latency)
{
        unsigned int smcr = SMCR_DTIM | SMCR_MBGE | FInsrt(drac, SMCR_DRAC);

        if (cas_latency == 3)
                smcr |= SMCR_CLAT;

        sa1111_writel(smcr, sachip->base + SA1111_SMCR);

        /*
         * Now clear the bits in the DMA mask to work around the SA1111
         * DMA erratum (Intel StrongARM SA-1111 Microprocessor Companion
         * Chip Specification Update, June 2000, Erratum #7).
         */
        if (sachip->dev->dma_mask)
                *sachip->dev->dma_mask &= sa1111_dma_mask[drac >> 2];

        sachip->dev->coherent_dma_mask &= sa1111_dma_mask[drac >> 2];
}

#endif

static void sa1111_dev_release(struct device *_dev)
{
        struct sa1111_dev *dev = SA1111_DEV(_dev);

        release_resource(&dev->res);
        kfree(dev);
}

static int
sa1111_init_one_child(struct sa1111 *sachip, struct resource *parent,
                      struct sa1111_dev_info *info)
{
        struct sa1111_dev *dev;
        int ret;

        dev = kzalloc(sizeof(struct sa1111_dev), GFP_KERNEL);
        if (!dev) {
                ret = -ENOMEM;
                goto out;
        }

        dev_set_name(&dev->dev, "%4.4lx", info->offset);
        dev->devid       = info->devid;
        dev->dev.parent  = sachip->dev;
        dev->dev.bus     = &sa1111_bus_type;
        dev->dev.release = sa1111_dev_release;
        dev->dev.coherent_dma_mask = sachip->dev->coherent_dma_mask;
        dev->res.start   = sachip->phys + info->offset;
        dev->res.end     = dev->res.start + 511;
        dev->res.name    = dev_name(&dev->dev);
        dev->res.flags   = IORESOURCE_MEM;
        dev->mapbase     = sachip->base + info->offset;
        dev->skpcr_mask  = info->skpcr_mask;
        memmove(dev->irq, info->irq, sizeof(dev->irq));

        ret = request_resource(parent, &dev->res);
        if (ret) {
                printk("SA1111: failed to allocate resource for %s\n",
                        dev->res.name);
                dev_set_name(&dev->dev, NULL);
                kfree(dev);
                goto out;
        }


        ret = device_register(&dev->dev);
        if (ret) {
                release_resource(&dev->res);
                kfree(dev);
                goto out;
        }

#ifdef CONFIG_DMABOUNCE
        /*
         * If the parent device has a DMA mask associated with it,
         * propagate it down to the children.
         */
        if (sachip->dev->dma_mask) {
                dev->dma_mask = *sachip->dev->dma_mask;
                dev->dev.dma_mask = &dev->dma_mask;

                if (dev->dma_mask != 0xffffffffUL) {
                        ret = dmabounce_register_dev(&dev->dev, 1024, 4096);
                        if (ret) {
                                dev_err(&dev->dev, "SA1111: Failed to register"
                                        " with dmabounce\n");
                                device_unregister(&dev->dev);
                        }
                }
        }
#endif

out:
        return ret;
}

/**
 *      sa1111_probe - probe for a single SA1111 chip.
 *      @phys_addr: physical address of device.
 *
 *      Probe for a SA1111 chip.  This must be called
 *      before any other SA1111-specific code.
 *
 *      Returns:
 *      %-ENODEV        device not found.
 *      %-EBUSY         physical address already marked in-use.
 *      %0              successful.
 */
static int
__sa1111_probe(struct device *me, struct resource *mem, int irq)
{
        struct sa1111 *sachip;
        unsigned long id;
        unsigned int has_devs;
        int i, ret = -ENODEV;

        sachip = kzalloc(sizeof(struct sa1111), GFP_KERNEL);
        if (!sachip)
                return -ENOMEM;

        sachip->clk = clk_get(me, "SA1111_CLK");
        if (IS_ERR(sachip->clk)) {
                ret = PTR_ERR(sachip->clk);
                goto err_free;
        }

        spin_lock_init(&sachip->lock);

        sachip->dev = me;
        dev_set_drvdata(sachip->dev, sachip);

        sachip->phys = mem->start;
        sachip->irq = irq;

        /*
         * Map the whole region.  This also maps the
         * registers for our children.
         */
        sachip->base = ioremap(mem->start, PAGE_SIZE * 2);
        if (!sachip->base) {
                ret = -ENOMEM;
                goto err_clkput;
        }

        /*
         * Probe for the chip.  Only touch the SBI registers.
         */
        id = sa1111_readl(sachip->base + SA1111_SKID);
        if ((id & SKID_ID_MASK) != SKID_SA1111_ID) {
                printk(KERN_DEBUG "SA1111 not detected: ID = %08lx\n", id);
                ret = -ENODEV;
                goto err_unmap;
        }

        printk(KERN_INFO "SA1111 Microprocessor Companion Chip: "
                "silicon revision %lx, metal revision %lx\n",
                (id & SKID_SIREV_MASK)>>4, (id & SKID_MTREV_MASK));

        /*
         * We found it.  Wake the chip up, and initialise.
         */
        sa1111_wake(sachip);

#ifdef CONFIG_ARCH_SA1100
        {
        unsigned int val;

        /*
         * The SDRAM configuration of the SA1110 and the SA1111 must
         * match.  This is very important to ensure that SA1111 accesses
         * don't corrupt the SDRAM.  Note that this ungates the SA1111's
         * MBGNT signal, so we must have called sa1110_mb_disable()
         * beforehand.
         */
        sa1111_configure_smc(sachip, 1,
                             FExtr(MDCNFG, MDCNFG_SA1110_DRAC0),
                             FExtr(MDCNFG, MDCNFG_SA1110_TDL0));

        /*
         * We only need to turn on DCLK whenever we want to use the
         * DMA.  It can otherwise be held firmly in the off position.
         * (currently, we always enable it.)
         */
        val = sa1111_readl(sachip->base + SA1111_SKPCR);
        sa1111_writel(val | SKPCR_DCLKEN, sachip->base + SA1111_SKPCR);

        /*
         * Enable the SA1110 memory bus request and grant signals.
         */
        sa1110_mb_enable();
        }
#endif

        /*
         * The interrupt controller must be initialised before any
         * other device to ensure that the interrupts are available.
         */
        if (sachip->irq != NO_IRQ)
                sa1111_setup_irq(sachip);

        g_sa1111 = sachip;

        has_devs = ~0;
        if (machine_is_assabet() || machine_is_jornada720() ||
            machine_is_badge4())
                has_devs &= ~(1 << 4);
        else
                has_devs &= ~(1 << 1);

        for (i = 0; i < ARRAY_SIZE(sa1111_devices); i++)
                if (has_devs & (1 << i))
                        sa1111_init_one_child(sachip, mem, &sa1111_devices[i]);

        return 0;

 err_unmap:
        iounmap(sachip->base);
 err_clkput:
        clk_put(sachip->clk);
 err_free:
        kfree(sachip);
        return ret;
}

static int sa1111_remove_one(struct device *dev, void *data)
{
        device_unregister(dev);
        return 0;
}

static void __sa1111_remove(struct sa1111 *sachip)
{
        void __iomem *irqbase = sachip->base + SA1111_INTC;

        device_for_each_child(sachip->dev, NULL, sa1111_remove_one);

        /* disable all IRQs */
        sa1111_writel(0, irqbase + SA1111_INTEN0);
        sa1111_writel(0, irqbase + SA1111_INTEN1);
        sa1111_writel(0, irqbase + SA1111_WAKEEN0);
        sa1111_writel(0, irqbase + SA1111_WAKEEN1);

        clk_disable(sachip->clk);

        if (sachip->irq != NO_IRQ) {
                set_irq_chained_handler(sachip->irq, NULL);
                set_irq_data(sachip->irq, NULL);

                release_mem_region(sachip->phys + SA1111_INTC, 512);
        }

        iounmap(sachip->base);
        clk_put(sachip->clk);
        kfree(sachip);
}

/*
 * According to the "Intel StrongARM SA-1111 Microprocessor Companion
 * Chip Specification Update" (June 2000), erratum #7, there is a
 * significant bug in the SA1111 SDRAM shared memory controller.  If
 * an access to a region of memory above 1MB relative to the bank base,
 * it is important that address bit 10 _NOT_ be asserted. Depending
 * on the configuration of the RAM, bit 10 may correspond to one
 * of several different (processor-relative) address bits.
 *
 * This routine only identifies whether or not a given DMA address
 * is susceptible to the bug.
 *
 * This should only get called for sa1111_device types due to the
 * way we configure our device dma_masks.
 */
int dma_needs_bounce(struct device *dev, dma_addr_t addr, size_t size)
{
        /*
         * Section 4.6 of the "Intel StrongARM SA-1111 Development Module
         * User's Guide" mentions that jumpers R51 and R52 control the
         * target of SA-1111 DMA (either SDRAM bank 0 on Assabet, or
         * SDRAM bank 1 on Neponset). The default configuration selects
         * Assabet, so any address in bank 1 is necessarily invalid.
         */
        return ((machine_is_assabet() || machine_is_pfs168()) &&
                (addr >= 0xc8000000 || (addr + size) >= 0xc8000000));
}

struct sa1111_save_data {
        unsigned int    skcr;
        unsigned int    skpcr;
        unsigned int    skcdr;
        unsigned char   skaud;
        unsigned char   skpwm0;
        unsigned char   skpwm1;

        /*
         * Interrupt controller
         */
        unsigned int    intpol0;
        unsigned int    intpol1;
        unsigned int    inten0;
        unsigned int    inten1;
        unsigned int    wakepol0;
        unsigned int    wakepol1;
        unsigned int    wakeen0;
        unsigned int    wakeen1;
};

#ifdef CONFIG_PM

static int sa1111_suspend(struct platform_device *dev, pm_message_t state)
{
        struct sa1111 *sachip = platform_get_drvdata(dev);
        struct sa1111_save_data *save;
        unsigned long flags;
        unsigned int val;
        void __iomem *base;

        save = kmalloc(sizeof(struct sa1111_save_data), GFP_KERNEL);
        if (!save)
                return -ENOMEM;
        sachip->saved_state = save;

        spin_lock_irqsave(&sachip->lock, flags);

        /*
         * Save state.
         */
        base = sachip->base;
        save->skcr     = sa1111_readl(base + SA1111_SKCR);
        save->skpcr    = sa1111_readl(base + SA1111_SKPCR);
        save->skcdr    = sa1111_readl(base + SA1111_SKCDR);
        save->skaud    = sa1111_readl(base + SA1111_SKAUD);
        save->skpwm0   = sa1111_readl(base + SA1111_SKPWM0);
        save->skpwm1   = sa1111_readl(base + SA1111_SKPWM1);

        base = sachip->base + SA1111_INTC;
        save->intpol0  = sa1111_readl(base + SA1111_INTPOL0);
        save->intpol1  = sa1111_readl(base + SA1111_INTPOL1);
        save->inten0   = sa1111_readl(base + SA1111_INTEN0);
        save->inten1   = sa1111_readl(base + SA1111_INTEN1);
        save->wakepol0 = sa1111_readl(base + SA1111_WAKEPOL0);
        save->wakepol1 = sa1111_readl(base + SA1111_WAKEPOL1);
        save->wakeen0  = sa1111_readl(base + SA1111_WAKEEN0);
        save->wakeen1  = sa1111_readl(base + SA1111_WAKEEN1);

        /*
         * Disable.
         */
        val = sa1111_readl(sachip->base + SA1111_SKCR);
        sa1111_writel(val | SKCR_SLEEP, sachip->base + SA1111_SKCR);
        sa1111_writel(0, sachip->base + SA1111_SKPWM0);
        sa1111_writel(0, sachip->base + SA1111_SKPWM1);

        clk_disable(sachip->clk);

        spin_unlock_irqrestore(&sachip->lock, flags);

        return 0;
}

/*
 *      sa1111_resume - Restore the SA1111 device state.
 *      @dev: device to restore
 *
 *      Restore the general state of the SA1111; clock control and
 *      interrupt controller.  Other parts of the SA1111 must be
 *      restored by their respective drivers, and must be called
 *      via LDM after this function.
 */
static int sa1111_resume(struct platform_device *dev)
{
        struct sa1111 *sachip = platform_get_drvdata(dev);
        struct sa1111_save_data *save;
        unsigned long flags, id;
        void __iomem *base;

        save = sachip->saved_state;
        if (!save)
                return 0;

        spin_lock_irqsave(&sachip->lock, flags);

        /*
         * Ensure that the SA1111 is still here.
         * FIXME: shouldn't do this here.
         */
        id = sa1111_readl(sachip->base + SA1111_SKID);
        if ((id & SKID_ID_MASK) != SKID_SA1111_ID) {
                __sa1111_remove(sachip);
                platform_set_drvdata(dev, NULL);
                kfree(save);
                return 0;
        }

        /*
         * First of all, wake up the chip.
         */
        sa1111_wake(sachip);
        sa1111_writel(0, sachip->base + SA1111_INTC + SA1111_INTEN0);
        sa1111_writel(0, sachip->base + SA1111_INTC + SA1111_INTEN1);

        base = sachip->base;
        sa1111_writel(save->skcr,     base + SA1111_SKCR);
        sa1111_writel(save->skpcr,    base + SA1111_SKPCR);
        sa1111_writel(save->skcdr,    base + SA1111_SKCDR);
        sa1111_writel(save->skaud,    base + SA1111_SKAUD);
        sa1111_writel(save->skpwm0,   base + SA1111_SKPWM0);
        sa1111_writel(save->skpwm1,   base + SA1111_SKPWM1);

        base = sachip->base + SA1111_INTC;
        sa1111_writel(save->intpol0,  base + SA1111_INTPOL0);
        sa1111_writel(save->intpol1,  base + SA1111_INTPOL1);
        sa1111_writel(save->inten0,   base + SA1111_INTEN0);
        sa1111_writel(save->inten1,   base + SA1111_INTEN1);
        sa1111_writel(save->wakepol0, base + SA1111_WAKEPOL0);
        sa1111_writel(save->wakepol1, base + SA1111_WAKEPOL1);
        sa1111_writel(save->wakeen0,  base + SA1111_WAKEEN0);
        sa1111_writel(save->wakeen1,  base + SA1111_WAKEEN1);

        spin_unlock_irqrestore(&sachip->lock, flags);

        sachip->saved_state = NULL;
        kfree(save);

        return 0;
}

#else
#define sa1111_suspend NULL
#define sa1111_resume  NULL
#endif

static int __devinit sa1111_probe(struct platform_device *pdev)
{
        struct resource *mem;
        int irq;

        mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!mem)
                return -EINVAL;
        irq = platform_get_irq(pdev, 0);
        if (irq < 0)
                return -ENXIO;

        return __sa1111_probe(&pdev->dev, mem, irq);
}

static int sa1111_remove(struct platform_device *pdev)
{
        struct sa1111 *sachip = platform_get_drvdata(pdev);

        if (sachip) {
                __sa1111_remove(sachip);
                platform_set_drvdata(pdev, NULL);

#ifdef CONFIG_PM
                kfree(sachip->saved_state);
                sachip->saved_state = NULL;
#endif
        }

        return 0;
}

/*
 *      Not sure if this should be on the system bus or not yet.
 *      We really want some way to register a system device at
 *      the per-machine level, and then have this driver pick
 *      up the registered devices.
 *
 *      We also need to handle the SDRAM configuration for
 *      PXA250/SA1110 machine classes.
 */
static struct platform_driver sa1111_device_driver = {
        .probe          = sa1111_probe,
        .remove         = sa1111_remove,
        .suspend        = sa1111_suspend,
        .resume         = sa1111_resume,
        .driver         = {
                .name   = "sa1111",
        },
};

/*
 *      Get the parent device driver (us) structure
 *      from a child function device
 */
static inline struct sa1111 *sa1111_chip_driver(struct sa1111_dev *sadev)
{
        return (struct sa1111 *)dev_get_drvdata(sadev->dev.parent);
}

/*
 * The bits in the opdiv field are non-linear.
 */
static unsigned char opdiv_table[] = { 1, 4, 2, 8 };

static unsigned int __sa1111_pll_clock(struct sa1111 *sachip)
{
        unsigned int skcdr, fbdiv, ipdiv, opdiv;

        skcdr = sa1111_readl(sachip->base + SA1111_SKCDR);

        fbdiv = (skcdr & 0x007f) + 2;
        ipdiv = ((skcdr & 0x0f80) >> 7) + 2;
        opdiv = opdiv_table[(skcdr & 0x3000) >> 12];

        return 3686400 * fbdiv / (ipdiv * opdiv);
}

/**
 *      sa1111_pll_clock - return the current PLL clock frequency.
 *      @sadev: SA1111 function block
 *
 *      BUG: we should look at SKCR.  We also blindly believe that
 *      the chip is being fed with the 3.6864MHz clock.
 *
 *      Returns the PLL clock in Hz.
 */
unsigned int sa1111_pll_clock(struct sa1111_dev *sadev)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);

        return __sa1111_pll_clock(sachip);
}

/**
 *      sa1111_select_audio_mode - select I2S or AC link mode
 *      @sadev: SA1111 function block
 *      @mode: One of %SA1111_AUDIO_ACLINK or %SA1111_AUDIO_I2S
 *
 *      Frob the SKCR to select AC Link mode or I2S mode for
 *      the audio block.
 */
void sa1111_select_audio_mode(struct sa1111_dev *sadev, int mode)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;

        spin_lock_irqsave(&sachip->lock, flags);

        val = sa1111_readl(sachip->base + SA1111_SKCR);
        if (mode == SA1111_AUDIO_I2S) {
                val &= ~SKCR_SELAC;
        } else {
                val |= SKCR_SELAC;
        }
        sa1111_writel(val, sachip->base + SA1111_SKCR);

        spin_unlock_irqrestore(&sachip->lock, flags);
}

/**
 *      sa1111_set_audio_rate - set the audio sample rate
 *      @sadev: SA1111 SAC function block
 *      @rate: sample rate to select
 */
int sa1111_set_audio_rate(struct sa1111_dev *sadev, int rate)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned int div;

        if (sadev->devid != SA1111_DEVID_SAC)
                return -EINVAL;

        div = (__sa1111_pll_clock(sachip) / 256 + rate / 2) / rate;
        if (div == 0)
                div = 1;
        if (div > 128)
                div = 128;

        sa1111_writel(div - 1, sachip->base + SA1111_SKAUD);

        return 0;
}

/**
 *      sa1111_get_audio_rate - get the audio sample rate
 *      @sadev: SA1111 SAC function block device
 */
int sa1111_get_audio_rate(struct sa1111_dev *sadev)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long div;

        if (sadev->devid != SA1111_DEVID_SAC)
                return -EINVAL;

        div = sa1111_readl(sachip->base + SA1111_SKAUD) + 1;

        return __sa1111_pll_clock(sachip) / (256 * div);
}

void sa1111_set_io_dir(struct sa1111_dev *sadev,
                       unsigned int bits, unsigned int dir,
                       unsigned int sleep_dir)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;
        void __iomem *gpio = sachip->base + SA1111_GPIO;

#define MODIFY_BITS(port, mask, dir)            \
        if (mask) {                             \
                val = sa1111_readl(port);       \
                val &= ~(mask);                 \
                val |= (dir) & (mask);          \
                sa1111_writel(val, port);       \
        }

        spin_lock_irqsave(&sachip->lock, flags);
        MODIFY_BITS(gpio + SA1111_GPIO_PADDR, bits & 15, dir);
        MODIFY_BITS(gpio + SA1111_GPIO_PBDDR, (bits >> 8) & 255, dir >> 8);
        MODIFY_BITS(gpio + SA1111_GPIO_PCDDR, (bits >> 16) & 255, dir >> 16);

        MODIFY_BITS(gpio + SA1111_GPIO_PASDR, bits & 15, sleep_dir);
        MODIFY_BITS(gpio + SA1111_GPIO_PBSDR, (bits >> 8) & 255, sleep_dir >> 8);
        MODIFY_BITS(gpio + SA1111_GPIO_PCSDR, (bits >> 16) & 255, sleep_dir >> 16);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

void sa1111_set_io(struct sa1111_dev *sadev, unsigned int bits, unsigned int v)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;
        void __iomem *gpio = sachip->base + SA1111_GPIO;

        spin_lock_irqsave(&sachip->lock, flags);
        MODIFY_BITS(gpio + SA1111_GPIO_PADWR, bits & 15, v);
        MODIFY_BITS(gpio + SA1111_GPIO_PBDWR, (bits >> 8) & 255, v >> 8);
        MODIFY_BITS(gpio + SA1111_GPIO_PCDWR, (bits >> 16) & 255, v >> 16);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

void sa1111_set_sleep_io(struct sa1111_dev *sadev, unsigned int bits, unsigned int v)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;
        void __iomem *gpio = sachip->base + SA1111_GPIO;

        spin_lock_irqsave(&sachip->lock, flags);
        MODIFY_BITS(gpio + SA1111_GPIO_PASSR, bits & 15, v);
        MODIFY_BITS(gpio + SA1111_GPIO_PBSSR, (bits >> 8) & 255, v >> 8);
        MODIFY_BITS(gpio + SA1111_GPIO_PCSSR, (bits >> 16) & 255, v >> 16);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

/*
 * Individual device operations.
 */

/**
 *      sa1111_enable_device - enable an on-chip SA1111 function block
 *      @sadev: SA1111 function block device to enable
 */
void sa1111_enable_device(struct sa1111_dev *sadev)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;

        spin_lock_irqsave(&sachip->lock, flags);
        val = sa1111_readl(sachip->base + SA1111_SKPCR);
        sa1111_writel(val | sadev->skpcr_mask, sachip->base + SA1111_SKPCR);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

/**
 *      sa1111_disable_device - disable an on-chip SA1111 function block
 *      @sadev: SA1111 function block device to disable
 */
void sa1111_disable_device(struct sa1111_dev *sadev)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;

        spin_lock_irqsave(&sachip->lock, flags);
        val = sa1111_readl(sachip->base + SA1111_SKPCR);
        sa1111_writel(val & ~sadev->skpcr_mask, sachip->base + SA1111_SKPCR);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

/*
 *      SA1111 "Register Access Bus."
 *
 *      We model this as a regular bus type, and hang devices directly
 *      off this.
 */
static int sa1111_match(struct device *_dev, struct device_driver *_drv)
{
        struct sa1111_dev *dev = SA1111_DEV(_dev);
        struct sa1111_driver *drv = SA1111_DRV(_drv);

        return dev->devid == drv->devid;
}

static int sa1111_bus_suspend(struct device *dev, pm_message_t state)
{
        struct sa1111_dev *sadev = SA1111_DEV(dev);
        struct sa1111_driver *drv = SA1111_DRV(dev->driver);
        int ret = 0;

        if (drv && drv->suspend)
                ret = drv->suspend(sadev, state);
        return ret;
}

static int sa1111_bus_resume(struct device *dev)
{
        struct sa1111_dev *sadev = SA1111_DEV(dev);
        struct sa1111_driver *drv = SA1111_DRV(dev->driver);
        int ret = 0;

        if (drv && drv->resume)
                ret = drv->resume(sadev);
        return ret;
}

static int sa1111_bus_probe(struct device *dev)
{
        struct sa1111_dev *sadev = SA1111_DEV(dev);
        struct sa1111_driver *drv = SA1111_DRV(dev->driver);
        int ret = -ENODEV;

        if (drv->probe)
                ret = drv->probe(sadev);
        return ret;
}

static int sa1111_bus_remove(struct device *dev)
{
        struct sa1111_dev *sadev = SA1111_DEV(dev);
        struct sa1111_driver *drv = SA1111_DRV(dev->driver);
        int ret = 0;

        if (drv->remove)
                ret = drv->remove(sadev);
        return ret;
}

struct bus_type sa1111_bus_type = {
        .name           = "sa1111-rab",
        .match          = sa1111_match,
        .probe          = sa1111_bus_probe,
        .remove         = sa1111_bus_remove,
        .suspend        = sa1111_bus_suspend,
        .resume         = sa1111_bus_resume,
};

int sa1111_driver_register(struct sa1111_driver *driver)
{
        driver->drv.bus = &sa1111_bus_type;
        return driver_register(&driver->drv);
}

void sa1111_driver_unregister(struct sa1111_driver *driver)
{
        driver_unregister(&driver->drv);
}

static int __init sa1111_init(void)
{
        int ret = bus_register(&sa1111_bus_type);
        if (ret == 0)
                platform_driver_register(&sa1111_device_driver);
        return ret;
}

static void __exit sa1111_exit(void)
{
        platform_driver_unregister(&sa1111_device_driver);
        bus_unregister(&sa1111_bus_type);
}

subsys_initcall(sa1111_init);
module_exit(sa1111_exit);

MODULE_DESCRIPTION("Intel Corporation SA1111 core driver");
MODULE_LICENSE("GPL");

EXPORT_SYMBOL(sa1111_select_audio_mode);
EXPORT_SYMBOL(sa1111_set_audio_rate);
EXPORT_SYMBOL(sa1111_get_audio_rate);
EXPORT_SYMBOL(sa1111_set_io_dir);
EXPORT_SYMBOL(sa1111_set_io);
EXPORT_SYMBOL(sa1111_set_sleep_io);
EXPORT_SYMBOL(sa1111_enable_device);
EXPORT_SYMBOL(sa1111_disable_device);
EXPORT_SYMBOL(sa1111_pll_clock);
EXPORT_SYMBOL(sa1111_bus_type);
EXPORT_SYMBOL(sa1111_driver_register);
EXPORT_SYMBOL(sa1111_driver_unregister);