viper.c

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/*
 *  linux/arch/arm/mach-pxa/viper.c
 *
 *  Support for the Arcom VIPER SBC.
 *
 *  Author: Ian Campbell
 *  Created:    Feb 03, 2003
 *  Copyright:  Arcom Control Systems
 *
 *  Maintained by Marc Zyngier <[email protected]>
 *                             <[email protected]>
 *
 * Based on lubbock.c:
 *  Author: Nicolas Pitre
 *  Created:    Jun 15, 2001
 *  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/types.h>
#include <linux/memory.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/delay.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/sched.h>
#include <linux/gpio.h>
#include <linux/jiffies.h>
#include <linux/i2c-gpio.h>
#include <linux/i2c/pxa-i2c.h>
#include <linux/serial_8250.h>
#include <linux/smc91x.h>
#include <linux/pwm_backlight.h>
#include <linux/usb/isp116x.h>
#include <linux/mtd/mtd.h>
#include <linux/mtd/partitions.h>
#include <linux/mtd/physmap.h>
#include <linux/syscore_ops.h>

#include <mach/pxa25x.h>
#include <mach/audio.h>
#include <linux/platform_data/video-pxafb.h>
#include <mach/regs-uart.h>
#include <linux/platform_data/pcmcia-pxa2xx_viper.h>
#include <mach/viper.h>

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

#include <asm/mach/arch.h>
#include <asm/mach/map.h>
#include <asm/mach/irq.h>

#include "generic.h"
#include "devices.h"

static unsigned int icr;

static void viper_icr_set_bit(unsigned int bit)
{
    icr |= bit;
    VIPER_ICR = icr;
}

static void viper_icr_clear_bit(unsigned int bit)
{
    icr &= ~bit;
    VIPER_ICR = icr;
}

/* This function is used from the pcmcia module to reset the CF */
static void viper_cf_reset(int state)
{
    if (state)
        viper_icr_set_bit(VIPER_ICR_CF_RST);
    else
        viper_icr_clear_bit(VIPER_ICR_CF_RST);
}

static struct arcom_pcmcia_pdata viper_pcmcia_info = {
    .cd_gpio    = VIPER_CF_CD_GPIO,
    .rdy_gpio   = VIPER_CF_RDY_GPIO,
    .pwr_gpio   = VIPER_CF_POWER_GPIO,
    .reset      = viper_cf_reset,
};

static struct platform_device viper_pcmcia_device = {
    .name       = "viper-pcmcia",
    .id     = -1,
    .dev        = {
        .platform_data  = &viper_pcmcia_info,
    },
};

/*
 * The CPLD version register was not present on VIPER boards prior to
 * v2i1. On v1 boards where the version register is not present we
 * will just read back the previous value from the databus.
 *
 * Therefore we do two reads. The first time we write 0 to the
 * (read-only) register before reading and the second time we write
 * 0xff first. If the two reads do not match or they read back as 0xff
 * or 0x00 then we have version 1 hardware.
 */
static u8 viper_hw_version(void)
{
    u8 v1, v2;
    unsigned long flags;

    local_irq_save(flags);

    VIPER_VERSION = 0;
    v1 = VIPER_VERSION;
    VIPER_VERSION = 0xff;
    v2 = VIPER_VERSION;

    v1 = (v1 != v2 || v1 == 0xff) ? 0 : v1;

    local_irq_restore(flags);
    return v1;
}

/* CPU system core operations. */
static int viper_cpu_suspend(void)
{
    viper_icr_set_bit(VIPER_ICR_R_DIS);
    return 0;
}

static void viper_cpu_resume(void)
{
    viper_icr_clear_bit(VIPER_ICR_R_DIS);
}

static struct syscore_ops viper_cpu_syscore_ops = {
    .suspend    = viper_cpu_suspend,
    .resume     = viper_cpu_resume,
};

static unsigned int current_voltage_divisor;

/*
 * If force is not true then step from existing to new divisor. If
 * force is true then jump straight to the new divisor. Stepping is
 * used because if the jump in voltage is too large, the VCC can dip
 * too low and the regulator cuts out.
 *
 * force can be used to initialize the divisor to a know state by
 * setting the value for the current clock speed, since we are already
 * running at that speed we know the voltage should be pretty close so
 * the jump won't be too large
 */
static void viper_set_core_cpu_voltage(unsigned long khz, int force)
{
    int i = 0;
    unsigned int divisor = 0;
    const char *v;

    if (khz < 200000) {
        v = "1.0"; divisor = 0xfff;
    } else if (khz < 300000) {
        v = "1.1"; divisor = 0xde5;
    } else {
        v = "1.3"; divisor = 0x325;
    }

    pr_debug("viper: setting CPU core voltage to %sV at %d.%03dMHz\n",
         v, (int)khz / 1000, (int)khz % 1000);

#define STEP 0x100
    do {
        int step;

        if (force)
            step = divisor;
        else if (current_voltage_divisor < divisor - STEP)
            step = current_voltage_divisor + STEP;
        else if (current_voltage_divisor > divisor + STEP)
            step = current_voltage_divisor - STEP;
        else
            step = divisor;
        force = 0;

        gpio_set_value(VIPER_PSU_CLK_GPIO, 0);
        gpio_set_value(VIPER_PSU_nCS_LD_GPIO, 0);

        for (i = 1 << 11 ; i > 0 ; i >>= 1) {
            udelay(1);

            gpio_set_value(VIPER_PSU_DATA_GPIO, step & i);
            udelay(1);

            gpio_set_value(VIPER_PSU_CLK_GPIO, 1);
            udelay(1);

            gpio_set_value(VIPER_PSU_CLK_GPIO, 0);
        }
        udelay(1);

        gpio_set_value(VIPER_PSU_nCS_LD_GPIO, 1);
        udelay(1);

        gpio_set_value(VIPER_PSU_nCS_LD_GPIO, 0);

        current_voltage_divisor = step;
    } while (current_voltage_divisor != divisor);
}

/* Interrupt handling */
static unsigned long viper_irq_enabled_mask;
static const int viper_isa_irqs[] = { 3, 4, 5, 6, 7, 10, 11, 12, 9, 14, 15 };
static const int viper_isa_irq_map[] = {
    0,      /* ISA irq #0, invalid */
    0,      /* ISA irq #1, invalid */
    0,      /* ISA irq #2, invalid */
    1 << 0,     /* ISA irq #3 */
    1 << 1,     /* ISA irq #4 */
    1 << 2,     /* ISA irq #5 */
    1 << 3,     /* ISA irq #6 */
    1 << 4,     /* ISA irq #7 */
    0,      /* ISA irq #8, invalid */
    1 << 8,     /* ISA irq #9 */
    1 << 5,     /* ISA irq #10 */
    1 << 6,     /* ISA irq #11 */
    1 << 7,     /* ISA irq #12 */
    0,      /* ISA irq #13, invalid */
    1 << 9,     /* ISA irq #14 */
    1 << 10,    /* ISA irq #15 */
};

static inline int viper_irq_to_bitmask(unsigned int irq)
{
    return viper_isa_irq_map[irq - PXA_ISA_IRQ(0)];
}

static inline int viper_bit_to_irq(int bit)
{
    return viper_isa_irqs[bit] + PXA_ISA_IRQ(0);
}

static void viper_ack_irq(struct irq_data *d)
{
    int viper_irq = viper_irq_to_bitmask(d->irq);

    if (viper_irq & 0xff)
        VIPER_LO_IRQ_STATUS = viper_irq;
    else
        VIPER_HI_IRQ_STATUS = (viper_irq >> 8);
}

static void viper_mask_irq(struct irq_data *d)
{
    viper_irq_enabled_mask &= ~(viper_irq_to_bitmask(d->irq));
}

static void viper_unmask_irq(struct irq_data *d)
{
    viper_irq_enabled_mask |= viper_irq_to_bitmask(d->irq);
}

static inline unsigned long viper_irq_pending(void)
{
    return (VIPER_HI_IRQ_STATUS << 8 | VIPER_LO_IRQ_STATUS) &
            viper_irq_enabled_mask;
}

static void viper_irq_handler(unsigned int irq, struct irq_desc *desc)
{
    unsigned long pending;

    pending = viper_irq_pending();
    do {
        /* we're in a chained irq handler,
         * so ack the interrupt by hand */
        desc->irq_data.chip->irq_ack(&desc->irq_data);

        if (likely(pending)) {
            irq = viper_bit_to_irq(__ffs(pending));
            generic_handle_irq(irq);
        }
        pending = viper_irq_pending();
    } while (pending);
}

static struct irq_chip viper_irq_chip = {
    .name       = "ISA",
    .irq_ack    = viper_ack_irq,
    .irq_mask   = viper_mask_irq,
    .irq_unmask = viper_unmask_irq
};

static void __init viper_init_irq(void)
{
    int level;
    int isa_irq;

    pxa25x_init_irq();

    /* setup ISA IRQs */
    for (level = 0; level < ARRAY_SIZE(viper_isa_irqs); level++) {
        isa_irq = viper_bit_to_irq(level);
        irq_set_chip_and_handler(isa_irq, &viper_irq_chip,
                     handle_edge_irq);
        set_irq_flags(isa_irq, IRQF_VALID | IRQF_PROBE);
    }

    irq_set_chained_handler(gpio_to_irq(VIPER_CPLD_GPIO),
                viper_irq_handler);
    irq_set_irq_type(gpio_to_irq(VIPER_CPLD_GPIO), IRQ_TYPE_EDGE_BOTH);
}

/* Flat Panel */
static struct pxafb_mode_info fb_mode_info[] = {
    {
        .pixclock   = 157500,

        .xres       = 320,
        .yres       = 240,

        .bpp        = 16,

        .hsync_len  = 63,
        .left_margin    = 7,
        .right_margin   = 13,

        .vsync_len  = 20,
        .upper_margin   = 0,
        .lower_margin   = 0,

        .sync       = 0,
    },
};

static struct pxafb_mach_info fb_info = {
    .modes          = fb_mode_info,
    .num_modes      = 1,
    .lcd_conn       = LCD_COLOR_TFT_16BPP | LCD_PCLK_EDGE_FALL,
};

static int viper_backlight_init(struct device *dev)
{
    int ret;

    /* GPIO9 and 10 control FB backlight. Initialise to off */
    ret = gpio_request(VIPER_BCKLIGHT_EN_GPIO, "Backlight");
    if (ret)
        goto err_request_bckl;

    ret = gpio_request(VIPER_LCD_EN_GPIO, "LCD");
    if (ret)
        goto err_request_lcd;

    ret = gpio_direction_output(VIPER_BCKLIGHT_EN_GPIO, 0);
    if (ret)
        goto err_dir;

    ret = gpio_direction_output(VIPER_LCD_EN_GPIO, 0);
    if (ret)
        goto err_dir;

    return 0;

err_dir:
    gpio_free(VIPER_LCD_EN_GPIO);
err_request_lcd:
    gpio_free(VIPER_BCKLIGHT_EN_GPIO);
err_request_bckl:
    dev_err(dev, "Failed to setup LCD GPIOs\n");

    return ret;
}

static int viper_backlight_notify(struct device *dev, int brightness)
{
    gpio_set_value(VIPER_LCD_EN_GPIO, !!brightness);
    gpio_set_value(VIPER_BCKLIGHT_EN_GPIO, !!brightness);

    return brightness;
}

static void viper_backlight_exit(struct device *dev)
{
    gpio_free(VIPER_LCD_EN_GPIO);
    gpio_free(VIPER_BCKLIGHT_EN_GPIO);
}

static struct platform_pwm_backlight_data viper_backlight_data = {
    .pwm_id     = 0,
    .max_brightness = 100,
    .dft_brightness = 100,
    .pwm_period_ns  = 1000000,
    .init       = viper_backlight_init,
    .notify     = viper_backlight_notify,
    .exit       = viper_backlight_exit,
};

static struct platform_device viper_backlight_device = {
    .name       = "pwm-backlight",
    .dev        = {
        .parent     = &pxa25x_device_pwm0.dev,
        .platform_data  = &viper_backlight_data,
    },
};

/* Ethernet */
static struct resource smc91x_resources[] = {
    [0] = {
        .name   = "smc91x-regs",
        .start  = VIPER_ETH_PHYS + 0x300,
        .end    = VIPER_ETH_PHYS + 0x30f,
        .flags  = IORESOURCE_MEM,
    },
    [1] = {
        .start  = PXA_GPIO_TO_IRQ(VIPER_ETH_GPIO),
        .end    = PXA_GPIO_TO_IRQ(VIPER_ETH_GPIO),
        .flags  = IORESOURCE_IRQ | IORESOURCE_IRQ_HIGHEDGE,
    },
    [2] = {
        .name   = "smc91x-data32",
        .start  = VIPER_ETH_DATA_PHYS,
        .end    = VIPER_ETH_DATA_PHYS + 3,
        .flags  = IORESOURCE_MEM,
    },
};

static struct smc91x_platdata viper_smc91x_info = {
    .flags  = SMC91X_USE_16BIT | SMC91X_NOWAIT,
    .leda   = RPC_LED_100_10,
    .ledb   = RPC_LED_TX_RX,
};

static struct platform_device smc91x_device = {
    .name       = "smc91x",
    .id     = -1,
    .num_resources  = ARRAY_SIZE(smc91x_resources),
    .resource       = smc91x_resources,
    .dev        = {
        .platform_data  = &viper_smc91x_info,
    },
};

/* i2c */
static struct i2c_gpio_platform_data i2c_bus_data = {
    .sda_pin = VIPER_RTC_I2C_SDA_GPIO,
    .scl_pin = VIPER_RTC_I2C_SCL_GPIO,
    .udelay  = 10,
    .timeout = HZ,
};

static struct platform_device i2c_bus_device = {
    .name       = "i2c-gpio",
    .id     = 1, /* pxa2xx-i2c is bus 0, so start at 1 */
    .dev = {
        .platform_data = &i2c_bus_data,
    }
};

static struct i2c_board_info __initdata viper_i2c_devices[] = {
    {
        I2C_BOARD_INFO("ds1338", 0x68),
    },
};

/*
 * Serial configuration:
 * You can either have the standard PXA ports driven by the PXA driver,
 * or all the ports (PXA + 16850) driven by the 8250 driver.
 * Choose your poison.
 */

static struct resource viper_serial_resources[] = {
#ifndef CONFIG_SERIAL_PXA
    {
        .start  = 0x40100000,
        .end    = 0x4010001f,
        .flags  = IORESOURCE_MEM,
    },
    {
        .start  = 0x40200000,
        .end    = 0x4020001f,
        .flags  = IORESOURCE_MEM,
    },
    {
        .start  = 0x40700000,
        .end    = 0x4070001f,
        .flags  = IORESOURCE_MEM,
    },
    {
        .start  = VIPER_UARTA_PHYS,
        .end    = VIPER_UARTA_PHYS + 0xf,
        .flags  = IORESOURCE_MEM,
    },
    {
        .start  = VIPER_UARTB_PHYS,
        .end    = VIPER_UARTB_PHYS + 0xf,
        .flags  = IORESOURCE_MEM,
    },
#else
    {
        0,
    },
#endif
};

static struct plat_serial8250_port serial_platform_data[] = {
#ifndef CONFIG_SERIAL_PXA
    /* Internal UARTs */
    {
        .membase    = (void *)&FFUART,
        .mapbase    = __PREG(FFUART),
        .irq        = IRQ_FFUART,
        .uartclk    = 921600 * 16,
        .regshift   = 2,
        .flags      = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
        .iotype     = UPIO_MEM,
    },
    {
        .membase    = (void *)&BTUART,
        .mapbase    = __PREG(BTUART),
        .irq        = IRQ_BTUART,
        .uartclk    = 921600 * 16,
        .regshift   = 2,
        .flags      = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
        .iotype     = UPIO_MEM,
    },
    {
        .membase    = (void *)&STUART,
        .mapbase    = __PREG(STUART),
        .irq        = IRQ_STUART,
        .uartclk    = 921600 * 16,
        .regshift   = 2,
        .flags      = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST,
        .iotype     = UPIO_MEM,
    },
    /* External UARTs */
    {
        .mapbase    = VIPER_UARTA_PHYS,
        .irq        = PXA_GPIO_TO_IRQ(VIPER_UARTA_GPIO),
        .irqflags   = IRQF_TRIGGER_RISING,
        .uartclk    = 1843200,
        .regshift   = 1,
        .iotype     = UPIO_MEM,
        .flags      = UPF_BOOT_AUTOCONF | UPF_IOREMAP |
                  UPF_SKIP_TEST,
    },
    {
        .mapbase    = VIPER_UARTB_PHYS,
        .irq        = PXA_GPIO_TO_IRQ(VIPER_UARTB_GPIO),
        .irqflags   = IRQF_TRIGGER_RISING,
        .uartclk    = 1843200,
        .regshift   = 1,
        .iotype     = UPIO_MEM,
        .flags      = UPF_BOOT_AUTOCONF | UPF_IOREMAP |
                  UPF_SKIP_TEST,
    },
#endif
    { },
};

static struct platform_device serial_device = {
    .name           = "serial8250",
    .id         = 0,
    .dev            = {
        .platform_data  = serial_platform_data,
    },
    .num_resources      = ARRAY_SIZE(viper_serial_resources),
    .resource       = viper_serial_resources,
};

/* USB */
static void isp116x_delay(struct device *dev, int delay)
{
    ndelay(delay);
}

static struct resource isp116x_resources[] = {
    [0] = { /* DATA */
        .start  = VIPER_USB_PHYS + 0,
        .end    = VIPER_USB_PHYS + 1,
        .flags  = IORESOURCE_MEM,
    },
    [1] = { /* ADDR */
        .start  = VIPER_USB_PHYS + 2,
        .end    = VIPER_USB_PHYS + 3,
        .flags  = IORESOURCE_MEM,
    },
    [2] = {
        .start  = PXA_GPIO_TO_IRQ(VIPER_USB_GPIO),
        .end    = PXA_GPIO_TO_IRQ(VIPER_USB_GPIO),
        .flags  = IORESOURCE_IRQ | IORESOURCE_IRQ_HIGHEDGE,
    },
};

/* (DataBusWidth16|AnalogOCEnable|DREQOutputPolarity|DownstreamPort15KRSel ) */
static struct isp116x_platform_data isp116x_platform_data = {
    /* Enable internal resistors on downstream ports */
    .sel15Kres      = 1,
    /* On-chip overcurrent protection */
    .oc_enable      = 1,
    /* INT output polarity */
    .int_act_high       = 1,
    /* INT edge or level triggered */
    .int_edge_triggered = 0,

    /* WAKEUP pin connected - NOT SUPPORTED  */
    /* .remote_wakeup_connected = 0, */
    /* Wakeup by devices on usb bus enabled */
    .remote_wakeup_enable   = 0,
    .delay          = isp116x_delay,
};

static struct platform_device isp116x_device = {
    .name           = "isp116x-hcd",
    .id         = -1,
    .num_resources      = ARRAY_SIZE(isp116x_resources),
    .resource           = isp116x_resources,
    .dev            = {
        .platform_data  = &isp116x_platform_data,
    },

};

/* MTD */
static struct resource mtd_resources[] = {
    [0] = { /* RedBoot config + filesystem flash */
        .start  = VIPER_FLASH_PHYS,
        .end    = VIPER_FLASH_PHYS + SZ_32M - 1,
        .flags  = IORESOURCE_MEM,
    },
    [1] = { /* Boot flash */
        .start  = VIPER_BOOT_PHYS,
        .end    = VIPER_BOOT_PHYS + SZ_1M - 1,
        .flags  = IORESOURCE_MEM,
    },
    [2] = { /*
         * SRAM size is actually 256KB, 8bits, with a sparse mapping
         * (each byte is on a 16bit boundary).
         */
        .start  = _VIPER_SRAM_BASE,
        .end    = _VIPER_SRAM_BASE + SZ_512K - 1,
        .flags  = IORESOURCE_MEM,
    },
};

static struct mtd_partition viper_boot_flash_partition = {
    .name       = "RedBoot",
    .size       = SZ_1M,
    .offset     = 0,
    .mask_flags = MTD_WRITEABLE,    /* force R/O */
};

static struct physmap_flash_data viper_flash_data[] = {
    [0] = {
        .width      = 2,
        .parts      = NULL,
        .nr_parts   = 0,
    },
    [1] = {
        .width      = 2,
        .parts      = &viper_boot_flash_partition,
        .nr_parts   = 1,
    },
};

static struct platform_device viper_mtd_devices[] = {
    [0] = {
        .name       = "physmap-flash",
        .id     = 0,
        .dev        = {
            .platform_data  = &viper_flash_data[0],
        },
        .resource   = &mtd_resources[0],
        .num_resources  = 1,
    },
    [1] = {
        .name       = "physmap-flash",
        .id     = 1,
        .dev        = {
            .platform_data  = &viper_flash_data[1],
        },
        .resource   = &mtd_resources[1],
        .num_resources  = 1,
    },
};

static struct platform_device *viper_devs[] __initdata = {
    &smc91x_device,
    &i2c_bus_device,
    &serial_device,
    &isp116x_device,
    &viper_mtd_devices[0],
    &viper_mtd_devices[1],
    &viper_backlight_device,
    &viper_pcmcia_device,
};

static mfp_cfg_t viper_pin_config[] __initdata = {
    /* Chip selects */
    GPIO15_nCS_1,
    GPIO78_nCS_2,
    GPIO79_nCS_3,
    GPIO80_nCS_4,
    GPIO33_nCS_5,

    /* AC97 */
    GPIO28_AC97_BITCLK,
    GPIO29_AC97_SDATA_IN_0,
    GPIO30_AC97_SDATA_OUT,
    GPIO31_AC97_SYNC,

    /* FP Backlight */
    GPIO9_GPIO,                 /* VIPER_BCKLIGHT_EN_GPIO */
    GPIO10_GPIO,                /* VIPER_LCD_EN_GPIO */
    GPIO16_PWM0_OUT,

    /* Ethernet PHY Ready */
    GPIO18_RDY,

    /* Serial shutdown */
    GPIO12_GPIO | MFP_LPM_DRIVE_HIGH,   /* VIPER_UART_SHDN_GPIO */

    /* Compact-Flash / PC104 */
    GPIO48_nPOE,
    GPIO49_nPWE,
    GPIO50_nPIOR,
    GPIO51_nPIOW,
    GPIO52_nPCE_1,
    GPIO53_nPCE_2,
    GPIO54_nPSKTSEL,
    GPIO55_nPREG,
    GPIO56_nPWAIT,
    GPIO57_nIOIS16,
    GPIO8_GPIO,             /* VIPER_CF_RDY_GPIO */
    GPIO32_GPIO,                /* VIPER_CF_CD_GPIO */
    GPIO82_GPIO,                /* VIPER_CF_POWER_GPIO */

    /* Integrated UPS control */
    GPIO20_GPIO,                /* VIPER_UPS_GPIO */

    /* Vcc regulator control */
    GPIO6_GPIO,             /* VIPER_PSU_DATA_GPIO */
    GPIO11_GPIO,                /* VIPER_PSU_CLK_GPIO */
    GPIO19_GPIO,                /* VIPER_PSU_nCS_LD_GPIO */

    /* i2c busses */
    GPIO26_GPIO,                /* VIPER_TPM_I2C_SDA_GPIO */
    GPIO27_GPIO,                /* VIPER_TPM_I2C_SCL_GPIO */
    GPIO83_GPIO,                /* VIPER_RTC_I2C_SDA_GPIO */
    GPIO84_GPIO,                /* VIPER_RTC_I2C_SCL_GPIO */

    /* PC/104 Interrupt */
    GPIO1_GPIO | WAKEUP_ON_EDGE_RISE,   /* VIPER_CPLD_GPIO */
};

static unsigned long viper_tpm;

static int __init viper_tpm_setup(char *str)
{
    return strict_strtoul(str, 10, &viper_tpm) >= 0;
}

__setup("tpm=", viper_tpm_setup);

static void __init viper_tpm_init(void)
{
    struct platform_device *tpm_device;
    struct i2c_gpio_platform_data i2c_tpm_data = {
        .sda_pin = VIPER_TPM_I2C_SDA_GPIO,
        .scl_pin = VIPER_TPM_I2C_SCL_GPIO,
        .udelay  = 10,
        .timeout = HZ,
    };
    char *errstr;

    /* Allocate TPM i2c bus if requested */
    if (!viper_tpm)
        return;

    tpm_device = platform_device_alloc("i2c-gpio", 2);
    if (tpm_device) {
        if (!platform_device_add_data(tpm_device,
                          &i2c_tpm_data,
                          sizeof(i2c_tpm_data))) {
            if (platform_device_add(tpm_device)) {
                errstr = "register TPM i2c bus";
                goto error_free_tpm;
            }
        } else {
            errstr = "allocate TPM i2c bus data";
            goto error_free_tpm;
        }
    } else {
        errstr = "allocate TPM i2c device";
        goto error_tpm;
    }

    return;

error_free_tpm:
    kfree(tpm_device);
error_tpm:
    pr_err("viper: Couldn't %s, giving up\n", errstr);
}

static void __init viper_init_vcore_gpios(void)
{
    if (gpio_request(VIPER_PSU_DATA_GPIO, "PSU data"))
        goto err_request_data;

    if (gpio_request(VIPER_PSU_CLK_GPIO, "PSU clock"))
        goto err_request_clk;

    if (gpio_request(VIPER_PSU_nCS_LD_GPIO, "PSU cs"))
        goto err_request_cs;

    if (gpio_direction_output(VIPER_PSU_DATA_GPIO, 0) ||
        gpio_direction_output(VIPER_PSU_CLK_GPIO, 0) ||
        gpio_direction_output(VIPER_PSU_nCS_LD_GPIO, 0))
        goto err_dir;

    /* c/should assume redboot set the correct level ??? */
    viper_set_core_cpu_voltage(get_clk_frequency_khz(0), 1);

    return;

err_dir:
    gpio_free(VIPER_PSU_nCS_LD_GPIO);
err_request_cs:
    gpio_free(VIPER_PSU_CLK_GPIO);
err_request_clk:
    gpio_free(VIPER_PSU_DATA_GPIO);
err_request_data:
    pr_err("viper: Failed to setup vcore control GPIOs\n");
}

static void __init viper_init_serial_gpio(void)
{
    if (gpio_request(VIPER_UART_SHDN_GPIO, "UARTs shutdown"))
        goto err_request;

    if (gpio_direction_output(VIPER_UART_SHDN_GPIO, 0))
        goto err_dir;

    return;

err_dir:
    gpio_free(VIPER_UART_SHDN_GPIO);
err_request:
    pr_err("viper: Failed to setup UART shutdown GPIO\n");
}

#ifdef CONFIG_CPU_FREQ
static int viper_cpufreq_notifier(struct notifier_block *nb,
                  unsigned long val, void *data)
{
    struct cpufreq_freqs *freq = data;

    /* TODO: Adjust timings??? */

    switch (val) {
    case CPUFREQ_PRECHANGE:
        if (freq->old < freq->new) {
            /* we are getting faster so raise the voltage
             * before we change freq */
            viper_set_core_cpu_voltage(freq->new, 0);
        }
        break;
    case CPUFREQ_POSTCHANGE:
        if (freq->old > freq->new) {
            /* we are slowing down so drop the power
             * after we change freq */
            viper_set_core_cpu_voltage(freq->new, 0);
        }
        break;
    case CPUFREQ_RESUMECHANGE:
        viper_set_core_cpu_voltage(freq->new, 0);
        break;
    default:
        /* ignore */
        break;
    }

    return 0;
}

static struct notifier_block viper_cpufreq_notifier_block = {
    .notifier_call  = viper_cpufreq_notifier
};

static void __init viper_init_cpufreq(void)
{
    if (cpufreq_register_notifier(&viper_cpufreq_notifier_block,
                      CPUFREQ_TRANSITION_NOTIFIER))
        pr_err("viper: Failed to setup cpufreq notifier\n");
}
#else
static inline void viper_init_cpufreq(void) {}
#endif

static void viper_power_off(void)
{
    pr_notice("Shutting off UPS\n");
    gpio_set_value(VIPER_UPS_GPIO, 1);
    /* Spin to death... */
    while (1);
}

static void __init viper_init(void)
{
    u8 version;

    pm_power_off = viper_power_off;

    pxa2xx_mfp_config(ARRAY_AND_SIZE(viper_pin_config));

    pxa_set_ffuart_info(NULL);
    pxa_set_btuart_info(NULL);
    pxa_set_stuart_info(NULL);

    /* Wake-up serial console */
    viper_init_serial_gpio();

    pxa_set_fb_info(NULL, &fb_info);

    /* v1 hardware cannot use the datacs line */
    version = viper_hw_version();
    if (version == 0)
        smc91x_device.num_resources--;

    pxa_set_i2c_info(NULL);
    platform_add_devices(viper_devs, ARRAY_SIZE(viper_devs));

    viper_init_vcore_gpios();
    viper_init_cpufreq();

    register_syscore_ops(&viper_cpu_syscore_ops);

    if (version) {
        pr_info("viper: hardware v%di%d detected. "
            "CPLD revision %d.\n",
            VIPER_BOARD_VERSION(version),
            VIPER_BOARD_ISSUE(version),
            VIPER_CPLD_REVISION(version));
        system_rev = (VIPER_BOARD_VERSION(version) << 8) |
                 (VIPER_BOARD_ISSUE(version) << 4) |
                 VIPER_CPLD_REVISION(version);
    } else {
        pr_info("viper: No version register.\n");
    }

    i2c_register_board_info(1, ARRAY_AND_SIZE(viper_i2c_devices));

    viper_tpm_init();
    pxa_set_ac97_info(NULL);
}

static struct map_desc viper_io_desc[] __initdata = {
    {
        .virtual = VIPER_CPLD_BASE,
        .pfn     = __phys_to_pfn(VIPER_CPLD_PHYS),
        .length  = 0x00300000,
        .type    = MT_DEVICE,
    },
    {
        .virtual = VIPER_PC104IO_BASE,
        .pfn     = __phys_to_pfn(0x30000000),
        .length  = 0x00800000,
        .type    = MT_DEVICE,
    },
};

static void __init viper_map_io(void)
{
    pxa25x_map_io();

    iotable_init(viper_io_desc, ARRAY_SIZE(viper_io_desc));

    PCFR |= PCFR_OPDE;
}

MACHINE_START(VIPER, "Arcom/Eurotech VIPER SBC")
    /* Maintainer: Marc Zyngier <[email protected]> */
    .atag_offset    = 0x100,
    .map_io     = viper_map_io,
    .nr_irqs    = PXA_NR_IRQS,
    .init_irq   = viper_init_irq,
    .handle_irq = pxa25x_handle_irq,
    .timer          = &pxa_timer,
    .init_machine   = viper_init,
    .restart    = pxa_restart,
MACHINE_END