treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

[mirror_ubuntu-hirsute-kernel.git] / arch / arm / common / sa1111.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * linux/arch/arm/common/sa1111.c
 *
 * SA1111 support
 *
 * Original code by John Dorsey
 *
 * 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/gpio/driver.h>
#include <linux/init.h>
#include <linux/irq.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/irq.h>
#include <asm/mach-types.h>
#include <linux/sizes.h>

#include <asm/hardware/sa1111.h>

/* SA1111 IRQs */
#define IRQ_GPAIN0              (0)
#define IRQ_GPAIN1              (1)
#define IRQ_GPAIN2              (2)
#define IRQ_GPAIN3              (3)
#define IRQ_GPBIN0              (4)
#define IRQ_GPBIN1              (5)
#define IRQ_GPBIN2              (6)
#define IRQ_GPBIN3              (7)
#define IRQ_GPBIN4              (8)
#define IRQ_GPBIN5              (9)
#define IRQ_GPCIN0              (10)
#define IRQ_GPCIN1              (11)
#define IRQ_GPCIN2              (12)
#define IRQ_GPCIN3              (13)
#define IRQ_GPCIN4              (14)
#define IRQ_GPCIN5              (15)
#define IRQ_GPCIN6              (16)
#define IRQ_GPCIN7              (17)
#define IRQ_MSTXINT             (18)
#define IRQ_MSRXINT             (19)
#define IRQ_MSSTOPERRINT        (20)
#define IRQ_TPTXINT             (21)
#define IRQ_TPRXINT             (22)
#define IRQ_TPSTOPERRINT        (23)
#define SSPXMTINT               (24)
#define SSPRCVINT               (25)
#define SSPROR                  (26)
#define AUDXMTDMADONEA          (32)
#define AUDRCVDMADONEA          (33)
#define AUDXMTDMADONEB          (34)
#define AUDRCVDMADONEB          (35)
#define AUDTFSR                 (36)
#define AUDRFSR                 (37)
#define AUDTUR                  (38)
#define AUDROR                  (39)
#define AUDDTS                  (40)
#define AUDRDD                  (41)
#define AUDSTO                  (42)
#define IRQ_USBPWR              (43)
#define IRQ_HCIM                (44)
#define IRQ_HCIBUFFACC          (45)
#define IRQ_HCIRMTWKP           (46)
#define IRQ_NHCIMFCIR           (47)
#define IRQ_USB_PORT_RESUME     (48)
#define IRQ_S0_READY_NINT       (49)
#define IRQ_S1_READY_NINT       (50)
#define IRQ_S0_CD_VALID         (51)
#define IRQ_S1_CD_VALID         (52)
#define IRQ_S0_BVD1_STSCHG      (53)
#define IRQ_S1_BVD1_STSCHG      (54)
#define SA1111_IRQ_NR           (55)

extern void sa1110_mb_enable(void);
extern void sa1110_mb_disable(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;
        int             irq_base;       /* base for cascaded on-chip IRQs */
        spinlock_t      lock;
        void __iomem    *base;
        struct sa1111_platform_data *pdata;
        struct irq_domain *irqdomain;
        struct gpio_chip gc;
#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;
        bool            dma;
        unsigned int    devid;
        unsigned int    hwirq[6];
};

static struct sa1111_dev_info sa1111_devices[] = {
        {
                .offset         = SA1111_USB,
                .skpcr_mask     = SKPCR_UCLKEN,
                .dma            = true,
                .devid          = SA1111_DEVID_USB,
                .hwirq = {
                        IRQ_USBPWR,
                        IRQ_HCIM,
                        IRQ_HCIBUFFACC,
                        IRQ_HCIRMTWKP,
                        IRQ_NHCIMFCIR,
                        IRQ_USB_PORT_RESUME
                },
        },
        {
                .offset         = 0x0600,
                .skpcr_mask     = SKPCR_I2SCLKEN | SKPCR_L3CLKEN,
                .dma            = true,
                .devid          = SA1111_DEVID_SAC,
                .hwirq = {
                        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_KBD,
                .hwirq = {
                        IRQ_TPRXINT,
                        IRQ_TPTXINT
                },
        },
        {
                .offset         = SA1111_MSE,
                .skpcr_mask     = SKPCR_PMCLKEN,
                .devid          = SA1111_DEVID_PS2_MSE,
                .hwirq = {
                        IRQ_MSRXINT,
                        IRQ_MSTXINT
                },
        },
        {
                .offset         = 0x1800,
                .skpcr_mask     = 0,
                .devid          = SA1111_DEVID_PCMCIA,
                .hwirq = {
                        IRQ_S0_READY_NINT,
                        IRQ_S0_CD_VALID,
                        IRQ_S0_BVD1_STSCHG,
                        IRQ_S1_READY_NINT,
                        IRQ_S1_CD_VALID,
                        IRQ_S1_BVD1_STSCHG,
                },
        },
};

static int sa1111_map_irq(struct sa1111 *sachip, irq_hw_number_t hwirq)
{
        return irq_create_mapping(sachip->irqdomain, hwirq);
}

static void sa1111_handle_irqdomain(struct irq_domain *irqdomain, int irq)
{
        struct irq_desc *d = irq_to_desc(irq_linear_revmap(irqdomain, irq));

        if (d)
                generic_handle_irq_desc(d);
}

/*
 * 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(struct irq_desc *desc)
{
        unsigned int stat0, stat1, i;
        struct sa1111 *sachip = irq_desc_get_handler_data(desc);
        struct irq_domain *irqdomain;
        void __iomem *mapbase = sachip->base + SA1111_INTC;

        stat0 = readl_relaxed(mapbase + SA1111_INTSTATCLR0);
        stat1 = readl_relaxed(mapbase + SA1111_INTSTATCLR1);

        writel_relaxed(stat0, mapbase + SA1111_INTSTATCLR0);

        desc->irq_data.chip->irq_ack(&desc->irq_data);

        writel_relaxed(stat1, mapbase + SA1111_INTSTATCLR1);

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

        irqdomain = sachip->irqdomain;

        for (i = 0; stat0; i++, stat0 >>= 1)
                if (stat0 & 1)
                        sa1111_handle_irqdomain(irqdomain, i);

        for (i = 32; stat1; i++, stat1 >>= 1)
                if (stat1 & 1)
                        sa1111_handle_irqdomain(irqdomain, i);

        /* For level-based interrupts */
        desc->irq_data.chip->irq_unmask(&desc->irq_data);
}

static u32 sa1111_irqmask(struct irq_data *d)
{
        return BIT(irqd_to_hwirq(d) & 31);
}

static int sa1111_irqbank(struct irq_data *d)
{
        return (irqd_to_hwirq(d) / 32) * 4;
}

static void sa1111_ack_irq(struct irq_data *d)
{
}

static void sa1111_mask_irq(struct irq_data *d)
{
        struct sa1111 *sachip = irq_data_get_irq_chip_data(d);
        void __iomem *mapbase = sachip->base + SA1111_INTC + sa1111_irqbank(d);
        u32 ie;

        ie = readl_relaxed(mapbase + SA1111_INTEN0);
        ie &= ~sa1111_irqmask(d);
        writel(ie, mapbase + SA1111_INTEN0);
}

static void sa1111_unmask_irq(struct irq_data *d)
{
        struct sa1111 *sachip = irq_data_get_irq_chip_data(d);
        void __iomem *mapbase = sachip->base + SA1111_INTC + sa1111_irqbank(d);
        u32 ie;

        ie = readl_relaxed(mapbase + SA1111_INTEN0);
        ie |= sa1111_irqmask(d);
        writel_relaxed(ie, 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_irq(struct irq_data *d)
{
        struct sa1111 *sachip = irq_data_get_irq_chip_data(d);
        void __iomem *mapbase = sachip->base + SA1111_INTC + sa1111_irqbank(d);
        u32 ip, mask = sa1111_irqmask(d);
        int i;

        ip = readl_relaxed(mapbase + SA1111_INTPOL0);
        for (i = 0; i < 8; i++) {
                writel_relaxed(ip ^ mask, mapbase + SA1111_INTPOL0);
                writel_relaxed(ip, mapbase + SA1111_INTPOL0);
                if (readl_relaxed(mapbase + SA1111_INTSTATCLR0) & mask)
                        break;
        }

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

static int sa1111_type_irq(struct irq_data *d, unsigned int flags)
{
        struct sa1111 *sachip = irq_data_get_irq_chip_data(d);
        void __iomem *mapbase = sachip->base + SA1111_INTC + sa1111_irqbank(d);
        u32 ip, mask = sa1111_irqmask(d);

        if (flags == IRQ_TYPE_PROBE)
                return 0;

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

        ip = readl_relaxed(mapbase + SA1111_INTPOL0);
        if (flags & IRQ_TYPE_EDGE_RISING)
                ip &= ~mask;
        else
                ip |= mask;
        writel_relaxed(ip, mapbase + SA1111_INTPOL0);
        writel_relaxed(ip, mapbase + SA1111_WAKEPOL0);

        return 0;
}

static int sa1111_wake_irq(struct irq_data *d, unsigned int on)
{
        struct sa1111 *sachip = irq_data_get_irq_chip_data(d);
        void __iomem *mapbase = sachip->base + SA1111_INTC + sa1111_irqbank(d);
        u32 we, mask = sa1111_irqmask(d);

        we = readl_relaxed(mapbase + SA1111_WAKEEN0);
        if (on)
                we |= mask;
        else
                we &= ~mask;
        writel_relaxed(we, mapbase + SA1111_WAKEEN0);

        return 0;
}

static struct irq_chip sa1111_irq_chip = {
        .name           = "SA1111",
        .irq_ack        = sa1111_ack_irq,
        .irq_mask       = sa1111_mask_irq,
        .irq_unmask     = sa1111_unmask_irq,
        .irq_retrigger  = sa1111_retrigger_irq,
        .irq_set_type   = sa1111_type_irq,
        .irq_set_wake   = sa1111_wake_irq,
};

static int sa1111_irqdomain_map(struct irq_domain *d, unsigned int irq,
        irq_hw_number_t hwirq)
{
        struct sa1111 *sachip = d->host_data;

        /* Disallow unavailable interrupts */
        if (hwirq > SSPROR && hwirq < AUDXMTDMADONEA)
                return -EINVAL;

        irq_set_chip_data(irq, sachip);
        irq_set_chip_and_handler(irq, &sa1111_irq_chip, handle_edge_irq);
        irq_clear_status_flags(irq, IRQ_NOREQUEST | IRQ_NOPROBE);

        return 0;
}

static const struct irq_domain_ops sa1111_irqdomain_ops = {
        .map = sa1111_irqdomain_map,
        .xlate = irq_domain_xlate_twocell,
};

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

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

        ret = irq_alloc_descs(-1, irq_base, SA1111_IRQ_NR, -1);
        if (ret <= 0) {
                dev_err(sachip->dev, "unable to allocate %u irqs: %d\n",
                        SA1111_IRQ_NR, ret);
                if (ret == 0)
                        ret = -EINVAL;
                return ret;
        }

        sachip->irq_base = ret;

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

        /*
         * detect on rising edge.  Note: Feb 2001 Errata for SA1111
         * specifies that S0ReadyInt and S1ReadyInt should be '1'.
         */
        writel_relaxed(0, irqbase + SA1111_INTPOL0);
        writel_relaxed(BIT(IRQ_S0_READY_NINT & 31) |
                       BIT(IRQ_S1_READY_NINT & 31),
                       irqbase + SA1111_INTPOL1);

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

        sachip->irqdomain = irq_domain_add_linear(NULL, SA1111_IRQ_NR,
                                                  &sa1111_irqdomain_ops,
                                                  sachip);
        if (!sachip->irqdomain) {
                irq_free_descs(sachip->irq_base, SA1111_IRQ_NR);
                return -ENOMEM;
        }

        irq_domain_associate_many(sachip->irqdomain,
                                  sachip->irq_base + IRQ_GPAIN0,
                                  IRQ_GPAIN0, SSPROR + 1 - IRQ_GPAIN0);
        irq_domain_associate_many(sachip->irqdomain,
                                  sachip->irq_base + AUDXMTDMADONEA,
                                  AUDXMTDMADONEA,
                                  IRQ_S1_BVD1_STSCHG + 1 - AUDXMTDMADONEA);

        /*
         * Register SA1111 interrupt
         */
        irq_set_irq_type(sachip->irq, IRQ_TYPE_EDGE_RISING);
        irq_set_chained_handler_and_data(sachip->irq, sa1111_irq_handler,
                                         sachip);

        dev_info(sachip->dev, "Providing IRQ%u-%u\n",
                sachip->irq_base, sachip->irq_base + SA1111_IRQ_NR - 1);

        return 0;
}

static void sa1111_remove_irq(struct sa1111 *sachip)
{
        struct irq_domain *domain = sachip->irqdomain;
        void __iomem *irqbase = sachip->base + SA1111_INTC;
        int i;

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

        irq_set_chained_handler_and_data(sachip->irq, NULL, NULL);
        for (i = 0; i < SA1111_IRQ_NR; i++)
                irq_dispose_mapping(irq_find_mapping(domain, i));
        irq_domain_remove(domain);

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

enum {
        SA1111_GPIO_PXDDR = (SA1111_GPIO_PADDR - SA1111_GPIO_PADDR),
        SA1111_GPIO_PXDRR = (SA1111_GPIO_PADRR - SA1111_GPIO_PADDR),
        SA1111_GPIO_PXDWR = (SA1111_GPIO_PADWR - SA1111_GPIO_PADDR),
        SA1111_GPIO_PXSDR = (SA1111_GPIO_PASDR - SA1111_GPIO_PADDR),
        SA1111_GPIO_PXSSR = (SA1111_GPIO_PASSR - SA1111_GPIO_PADDR),
};

static struct sa1111 *gc_to_sa1111(struct gpio_chip *gc)
{
        return container_of(gc, struct sa1111, gc);
}

static void __iomem *sa1111_gpio_map_reg(struct sa1111 *sachip, unsigned offset)
{
        void __iomem *reg = sachip->base + SA1111_GPIO;

        if (offset < 4)
                return reg + SA1111_GPIO_PADDR;
        if (offset < 10)
                return reg + SA1111_GPIO_PBDDR;
        if (offset < 18)
                return reg + SA1111_GPIO_PCDDR;
        return NULL;
}

static u32 sa1111_gpio_map_bit(unsigned offset)
{
        if (offset < 4)
                return BIT(offset);
        if (offset < 10)
                return BIT(offset - 4);
        if (offset < 18)
                return BIT(offset - 10);
        return 0;
}

static void sa1111_gpio_modify(void __iomem *reg, u32 mask, u32 set)
{
        u32 val;

        val = readl_relaxed(reg);
        val &= ~mask;
        val |= mask & set;
        writel_relaxed(val, reg);
}

static int sa1111_gpio_get_direction(struct gpio_chip *gc, unsigned offset)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);
        void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);
        u32 mask = sa1111_gpio_map_bit(offset);

        return !!(readl_relaxed(reg + SA1111_GPIO_PXDDR) & mask);
}

static int sa1111_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);
        unsigned long flags;
        void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);
        u32 mask = sa1111_gpio_map_bit(offset);

        spin_lock_irqsave(&sachip->lock, flags);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXDDR, mask, mask);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXSDR, mask, mask);
        spin_unlock_irqrestore(&sachip->lock, flags);

        return 0;
}

static int sa1111_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
        int value)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);
        unsigned long flags;
        void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);
        u32 mask = sa1111_gpio_map_bit(offset);

        spin_lock_irqsave(&sachip->lock, flags);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXDWR, mask, value ? mask : 0);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXSSR, mask, value ? mask : 0);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXDDR, mask, 0);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXSDR, mask, 0);
        spin_unlock_irqrestore(&sachip->lock, flags);

        return 0;
}

static int sa1111_gpio_get(struct gpio_chip *gc, unsigned offset)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);
        void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);
        u32 mask = sa1111_gpio_map_bit(offset);

        return !!(readl_relaxed(reg + SA1111_GPIO_PXDRR) & mask);
}

static void sa1111_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);
        unsigned long flags;
        void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);
        u32 mask = sa1111_gpio_map_bit(offset);

        spin_lock_irqsave(&sachip->lock, flags);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXDWR, mask, value ? mask : 0);
        sa1111_gpio_modify(reg + SA1111_GPIO_PXSSR, mask, value ? mask : 0);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

static void sa1111_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,
        unsigned long *bits)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);
        unsigned long flags;
        void __iomem *reg = sachip->base + SA1111_GPIO;
        u32 msk, val;

        msk = *mask;
        val = *bits;

        spin_lock_irqsave(&sachip->lock, flags);
        sa1111_gpio_modify(reg + SA1111_GPIO_PADWR, msk & 15, val);
        sa1111_gpio_modify(reg + SA1111_GPIO_PASSR, msk & 15, val);
        sa1111_gpio_modify(reg + SA1111_GPIO_PBDWR, (msk >> 4) & 255, val >> 4);
        sa1111_gpio_modify(reg + SA1111_GPIO_PBSSR, (msk >> 4) & 255, val >> 4);
        sa1111_gpio_modify(reg + SA1111_GPIO_PCDWR, (msk >> 12) & 255, val >> 12);
        sa1111_gpio_modify(reg + SA1111_GPIO_PCSSR, (msk >> 12) & 255, val >> 12);
        spin_unlock_irqrestore(&sachip->lock, flags);
}

static int sa1111_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
{
        struct sa1111 *sachip = gc_to_sa1111(gc);

        return sa1111_map_irq(sachip, offset);
}

static int sa1111_setup_gpios(struct sa1111 *sachip)
{
        sachip->gc.label = "sa1111";
        sachip->gc.parent = sachip->dev;
        sachip->gc.owner = THIS_MODULE;
        sachip->gc.get_direction = sa1111_gpio_get_direction;
        sachip->gc.direction_input = sa1111_gpio_direction_input;
        sachip->gc.direction_output = sa1111_gpio_direction_output;
        sachip->gc.get = sa1111_gpio_get;
        sachip->gc.set = sa1111_gpio_set;
        sachip->gc.set_multiple = sa1111_gpio_set_multiple;
        sachip->gc.to_irq = sa1111_gpio_to_irq;
        sachip->gc.base = -1;
        sachip->gc.ngpio = 18;

        return devm_gpiochip_add_data(sachip->dev, &sachip->gc, sachip);
}

/*
 * 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 = readl_relaxed(sachip->base + SA1111_SKCR);
        r &= ~SKCR_VCO_OFF;
        writel_relaxed(r, sachip->base + SA1111_SKCR);
        r |= SKCR_PLL_BYPASS | SKCR_OE_EN;
        writel_relaxed(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;
        writel_relaxed(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.
         */
        writel_relaxed(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;

        writel_relaxed(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 = to_sa1111_device(_dev);

        kfree(dev);
}

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

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

        device_initialize(&dev->dev);
        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->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;

        for (i = 0; i < ARRAY_SIZE(info->hwirq); i++)
                dev->hwirq[i] = info->hwirq[i];

        /*
         * If the parent device has a DMA mask associated with it, and
         * this child supports DMA, propagate it down to the children.
         */
        if (info->dma && sachip->dev->dma_mask) {
                dev->dma_mask = *sachip->dev->dma_mask;
                dev->dev.dma_mask = &dev->dma_mask;
                dev->dev.coherent_dma_mask = sachip->dev->coherent_dma_mask;
        }

        ret = request_resource(parent, &dev->res);
        if (ret) {
                dev_err(sachip->dev, "failed to allocate resource for %s\n",
                        dev->res.name);
                goto err_resource;
        }

        ret = device_add(&dev->dev);
        if (ret)
                goto err_add;
        return 0;

 err_add:
        release_resource(&dev->res);
 err_resource:
        put_device(&dev->dev);
 err_alloc:
        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.
 *      %-EINVAL        no platform data passed
 *      %0              successful.
 */
static int __sa1111_probe(struct device *me, struct resource *mem, int irq)
{
        struct sa1111_platform_data *pd = me->platform_data;
        struct sa1111 *sachip;
        unsigned long id;
        unsigned int has_devs;
        int i, ret = -ENODEV;

        if (!pd)
                return -EINVAL;

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

        sachip->clk = devm_clk_get(me, "SA1111_CLK");
        if (IS_ERR(sachip->clk))
                return PTR_ERR(sachip->clk);

        ret = clk_prepare(sachip->clk);
        if (ret)
                return ret;

        spin_lock_init(&sachip->lock);

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

        sachip->pdata = pd;
        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_clk_unprep;
        }

        /*
         * Probe for the chip.  Only touch the SBI registers.
         */
        id = readl_relaxed(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;
        }

        pr_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);

        /*
         * The interrupt controller must be initialised before any
         * other device to ensure that the interrupts are available.
         */
        ret = sa1111_setup_irq(sachip, pd->irq_base);
        if (ret)
                goto err_clk;

        /* Setup the GPIOs - should really be done after the IRQ setup */
        ret = sa1111_setup_gpios(sachip);
        if (ret)
                goto err_irq;

#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 = readl_relaxed(sachip->base + SA1111_SKPCR);
        writel_relaxed(val | SKPCR_DCLKEN, sachip->base + SA1111_SKPCR);

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

        g_sa1111 = sachip;

        has_devs = ~0;
        if (pd)
                has_devs &= ~pd->disable_devs;

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

        return 0;

 err_irq:
        sa1111_remove_irq(sachip);
 err_clk:
        clk_disable(sachip->clk);
 err_unmap:
        iounmap(sachip->base);
 err_clk_unprep:
        clk_unprepare(sachip->clk);
        return ret;
}

static int sa1111_remove_one(struct device *dev, void *data)
{
        struct sa1111_dev *sadev = to_sa1111_device(dev);
        if (dev->bus != &sa1111_bus_type)
                return 0;
        device_del(&sadev->dev);
        release_resource(&sadev->res);
        put_device(&sadev->dev);
        return 0;
}

static void __sa1111_remove(struct sa1111 *sachip)
{
        device_for_each_child(sachip->dev, NULL, sa1111_remove_one);

        sa1111_remove_irq(sachip);

        clk_disable(sachip->clk);
        clk_unprepare(sachip->clk);

        iounmap(sachip->base);
}

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_noirq(struct device *dev)
{
        struct sa1111 *sachip = dev_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     = readl_relaxed(base + SA1111_SKCR);
        save->skpcr    = readl_relaxed(base + SA1111_SKPCR);
        save->skcdr    = readl_relaxed(base + SA1111_SKCDR);
        save->skaud    = readl_relaxed(base + SA1111_SKAUD);
        save->skpwm0   = readl_relaxed(base + SA1111_SKPWM0);
        save->skpwm1   = readl_relaxed(base + SA1111_SKPWM1);

        writel_relaxed(0, sachip->base + SA1111_SKPWM0);
        writel_relaxed(0, sachip->base + SA1111_SKPWM1);

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

        /*
         * Disable.
         */
        val = readl_relaxed(sachip->base + SA1111_SKCR);
        writel_relaxed(val | SKCR_SLEEP, sachip->base + SA1111_SKCR);

        clk_disable(sachip->clk);

        spin_unlock_irqrestore(&sachip->lock, flags);

#ifdef CONFIG_ARCH_SA1100
        sa1110_mb_disable();
#endif

        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_noirq(struct device *dev)
{
        struct sa1111 *sachip = dev_get_drvdata(dev);
        struct sa1111_save_data *save;
        unsigned long flags, id;
        void __iomem *base;

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

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

        /*
         * First of all, wake up the chip.
         */
        sa1111_wake(sachip);

#ifdef CONFIG_ARCH_SA1100
        /* Enable the memory bus request/grant signals */
        sa1110_mb_enable();
#endif

        /*
         * Only lock for write ops. Also, sa1111_wake must be called with
         * released spinlock!
         */
        spin_lock_irqsave(&sachip->lock, flags);

        writel_relaxed(0, sachip->base + SA1111_INTC + SA1111_INTEN0);
        writel_relaxed(0, sachip->base + SA1111_INTC + SA1111_INTEN1);

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

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

        spin_unlock_irqrestore(&sachip->lock, flags);

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

        return 0;
}

#else
#define sa1111_suspend_noirq NULL
#define sa1111_resume_noirq  NULL
#endif

static int 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 irq;

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

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

        if (sachip) {
#ifdef CONFIG_PM
                kfree(sachip->saved_state);
                sachip->saved_state = NULL;
#endif
                __sa1111_remove(sachip);
                platform_set_drvdata(pdev, NULL);
        }

        return 0;
}

static struct dev_pm_ops sa1111_pm_ops = {
        .suspend_noirq = sa1111_suspend_noirq,
        .resume_noirq = sa1111_resume_noirq,
};

/*
 *      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,
        .driver         = {
                .name   = "sa1111",
                .pm     = &sa1111_pm_ops,
        },
};

/*
 *      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 = readl_relaxed(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);
}
EXPORT_SYMBOL(sa1111_pll_clock);

/**
 *      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 = readl_relaxed(sachip->base + SA1111_SKCR);
        if (mode == SA1111_AUDIO_I2S) {
                val &= ~SKCR_SELAC;
        } else {
                val |= SKCR_SELAC;
        }
        writel_relaxed(val, sachip->base + SA1111_SKCR);

        spin_unlock_irqrestore(&sachip->lock, flags);
}
EXPORT_SYMBOL(sa1111_select_audio_mode);

/**
 *      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;

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

        return 0;
}
EXPORT_SYMBOL(sa1111_set_audio_rate);

/**
 *      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 = readl_relaxed(sachip->base + SA1111_SKAUD) + 1;

        return __sa1111_pll_clock(sachip) / (256 * div);
}
EXPORT_SYMBOL(sa1111_get_audio_rate);

/*
 * Individual device operations.
 */

/**
 *      sa1111_enable_device - enable an on-chip SA1111 function block
 *      @sadev: SA1111 function block device to enable
 */
int sa1111_enable_device(struct sa1111_dev *sadev)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        unsigned long flags;
        unsigned int val;
        int ret = 0;

        if (sachip->pdata && sachip->pdata->enable)
                ret = sachip->pdata->enable(sachip->pdata->data, sadev->devid);

        if (ret == 0) {
                spin_lock_irqsave(&sachip->lock, flags);
                val = readl_relaxed(sachip->base + SA1111_SKPCR);
                writel_relaxed(val | sadev->skpcr_mask, sachip->base + SA1111_SKPCR);
                spin_unlock_irqrestore(&sachip->lock, flags);
        }
        return ret;
}
EXPORT_SYMBOL(sa1111_enable_device);

/**
 *      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 = readl_relaxed(sachip->base + SA1111_SKPCR);
        writel_relaxed(val & ~sadev->skpcr_mask, sachip->base + SA1111_SKPCR);
        spin_unlock_irqrestore(&sachip->lock, flags);

        if (sachip->pdata && sachip->pdata->disable)
                sachip->pdata->disable(sachip->pdata->data, sadev->devid);
}
EXPORT_SYMBOL(sa1111_disable_device);

int sa1111_get_irq(struct sa1111_dev *sadev, unsigned num)
{
        struct sa1111 *sachip = sa1111_chip_driver(sadev);
        if (num >= ARRAY_SIZE(sadev->hwirq))
                return -EINVAL;
        return sa1111_map_irq(sachip, sadev->hwirq[num]);
}
EXPORT_SYMBOL_GPL(sa1111_get_irq);

/*
 *      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 = to_sa1111_device(_dev);
        struct sa1111_driver *drv = SA1111_DRV(_drv);

        return !!(dev->devid & drv->devid);
}

static int sa1111_bus_probe(struct device *dev)
{
        struct sa1111_dev *sadev = to_sa1111_device(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 = to_sa1111_device(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,
};
EXPORT_SYMBOL(sa1111_bus_type);

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

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

#ifdef CONFIG_DMABOUNCE
/*
 * 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.
 */
static int sa1111_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);
}

static int sa1111_notifier_call(struct notifier_block *n, unsigned long action,
        void *data)
{
        struct sa1111_dev *dev = to_sa1111_device(data);

        switch (action) {
        case BUS_NOTIFY_ADD_DEVICE:
                if (dev->dev.dma_mask && dev->dma_mask < 0xffffffffUL) {
                        int ret = dmabounce_register_dev(&dev->dev, 1024, 4096,
                                        sa1111_needs_bounce);
                        if (ret)
                                dev_err(&dev->dev, "failed to register with dmabounce: %d\n", ret);
                }
                break;

        case BUS_NOTIFY_DEL_DEVICE:
                if (dev->dev.dma_mask && dev->dma_mask < 0xffffffffUL)
                        dmabounce_unregister_dev(&dev->dev);
                break;
        }
        return NOTIFY_OK;
}

static struct notifier_block sa1111_bus_notifier = {
        .notifier_call = sa1111_notifier_call,
};
#endif

static int __init sa1111_init(void)
{
        int ret = bus_register(&sa1111_bus_type);
#ifdef CONFIG_DMABOUNCE
        if (ret == 0)
                bus_register_notifier(&sa1111_bus_type, &sa1111_bus_notifier);
#endif
        if (ret == 0)
                platform_driver_register(&sa1111_device_driver);
        return ret;
}

static void __exit sa1111_exit(void)
{
        platform_driver_unregister(&sa1111_device_driver);
#ifdef CONFIG_DMABOUNCE
        bus_unregister_notifier(&sa1111_bus_type, &sa1111_bus_notifier);
#endif
        bus_unregister(&sa1111_bus_type);
}

subsys_initcall(sa1111_init);
module_exit(sa1111_exit);

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