Driver to access a memory mapped device

Question

Hi,
I've got a memory mapped device, but the OS (Solaris 10) doesn't let me access it in user space without a driver. So, I need to write a driver to bind the driver to my device at location 0x7fff00000000. I've followed the Device Driver Tutorial and examples on Sun's website, and came up with the following code. But when I mmap the driver into user space, the device at 0x7fff00000000 is not accessed at all. So, I believe there is a problem in probing and attaching the device. Could you please take a look at my code and tell me what I'm doing wrong? I'm new to device drivers. Thank you.
static int
foo_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
        int instance = ddi_get_instance(dip);
        struct foo_state *fsp;
        switch (cmd) {
        case DDI_ATTACH:
                if (ddi_soft_state_zalloc(foo_state_head, instance)
                    != DDI_SUCCESS) {
                        cmn_err(CE_WARN, "Unable to allocate state for %d",
                            instance);
                        return (DDI_FAILURE);
                if ((fsp = ddi_get_soft_state(foo_state_head, instance))
                    == NULL) {
                        cmn_err(CE_WARN, "Unable to obtain state for %d",
                            instance);
                        ddi_soft_state_free(dip, instance);
                        return (DDI_FAILURE);
                if (ddi_create_minor_node(dip, "foo", S_IFCHR, instance,
                    DDI_PSEUDO, 0) != DDI_SUCCESS) {
                        cmn_err(CE_WARN, "Cannot create minor node for %d",
                            instance);
                        ddi_soft_state_free(dip, instance);
                        ddi_remove_minor_node(dip, NULL);
                        return (DDI_FAILURE);
                fsp->instance = instance;
                fsp->dev = dip;
                ddi_report_dev(dip);
                return (DDI_SUCCESS);
        case DDI_RESUME:
                return (DDI_SUCCESS);
        default:
                return (DDI_FAILURE);
static int
foo_devmap(dev_t dev, devmap_cookie_t handle, offset_t off, size_t len,
    size_t *maplen, uint_t model)
    struct foo_state *fsp;
    int error, rnumber;
    off_t regsize;
    /* Set up data access attribute structure */
    struct ddi_device_acc_attr foo_acc_attr = {
        DDI_DEVICE_ATTR_V0,
        DDI_STRUCTURE_BE_ACC,
        DDI_STRICTORDER_ACC
    fsp = ddi_get_soft_state(foo_state_head, getminor(dev));
    if (fsp == NULL)
        return (-1);
    /* use register set 0 */
    rnumber = 0;
    /* get size of register set */
    if (ddi_dev_regsize(fsp->dev, rnumber, &regsize) != DDI_SUCCESS)
        return (-1);
    /* round up len to a multiple of a page size */
    len = ptob(btopr(len));
    if (off + len > regsize)
        return (-1);
    /* Set up the device mapping */
    error = devmap_devmem_setup(handle, fsp->dev, NULL, rnumber,
       off, len, PROT_ALL, DEVMAP_DEFAULTS, &foo_acc_attr);
    /* acknowledge the entire range */
    *maplen = len;
    return (error);
static int
foo_segmap(dev_t dev, off_t off, struct as *asp, caddr_t *addrp,
     off_t len, unsigned int prot, unsigned int maxprot,
     unsigned int flags, cred_t *credp)
     return (ddi_devmap_segmap(dev, off, asp, addrp,
          len, prot, maxprot, flags, credp));
}

Answer 1

Hi java_user,
There are no EBIU VIs. You will need to use C code for that part of your application.
Mike Lyons
National Instruments
http://www.ni.com/devzone