/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <sys/stat.h>           /* ddi_create_minor_node S_IFCHR */
#include <sys/modctl.h>         /* for modldrv */
#include <sys/open.h>           /* for open params.      */
#include <sys/types.h>
#include <sys/kmem.h>
#include <sys/sunddi.h>
#include <sys/conf.h>           /* req. by dev_ops flags MTSAFE etc. */
#include <sys/ddi.h>
#include <sys/file.h>
#include <sys/note.h>

#include <sys/i2c/clients/ssc100_impl.h>

static void *ssc100soft_statep;

static int ssc100_do_attach(dev_info_t *);
static int ssc100_do_detach(dev_info_t *);
static int ssc100_do_resume(void);
static int ssc100_do_suspend(void);
static int ssc100_get(struct ssc100_unit *, uchar_t *);
static int ssc100_set(struct ssc100_unit *, uchar_t);
static int ssc100_get_reg(struct ssc100_unit *, uchar_t *, uchar_t);
static int ssc100_common(struct ssc100_unit *, uchar_t *, uchar_t, int8_t);
static int ssc100_read(dev_t, struct uio *, cred_t *);
static int ssc100_write(dev_t, struct uio *, cred_t *);
static int ssc100_io(dev_t, struct uio *, int);

/*
 * cb ops (only need ioctl)
 */
static int ssc100_open(dev_t *, int, int, cred_t *);
static int ssc100_close(dev_t, int, int, cred_t *);
static int ssc100_ioctl(dev_t, int, intptr_t, int, cred_t *, int *);

static struct cb_ops ssc100_cbops = {
        ssc100_open,                    /* open  */
        ssc100_close,                   /* close */
        nodev,                          /* strategy */
        nodev,                          /* print */
        nodev,                          /* dump */
        ssc100_read,                    /* read */
        ssc100_write,                   /* write */
        ssc100_ioctl,                   /* ioctl */
        nodev,                          /* devmap */
        nodev,                          /* mmap */
        nodev,                          /* segmap */
        nochpoll,                       /* poll */
        ddi_prop_op,                    /* cb_prop_op */
        NULL,                           /* streamtab */
        D_NEW | D_MP | D_HOTPLUG,       /* Driver compatibility flag */
        CB_REV,                         /* rev */
        nodev,                          /* int (*cb_aread)() */
        nodev                           /* int (*cb_awrite)() */
};

/*
 * dev ops
 */
static int ssc100_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
static int ssc100_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);

static struct dev_ops ssc100_ops = {
        DEVO_REV,
        0,
        ddi_getinfo_1to1,
        nulldev,
        nulldev,
        ssc100_attach,
        ssc100_detach,
        nodev,
        &ssc100_cbops,
        NULL,
        NULL,
        ddi_quiesce_not_needed,         /* quiesce */
};

extern struct mod_ops mod_driverops;

static struct modldrv ssc100_modldrv = {
        &mod_driverops,                 /* type of module - driver */
        "SSC100 i2c device driver",
        &ssc100_ops
};

static struct modlinkage ssc100_modlinkage = {
        MODREV_1,
        &ssc100_modldrv,
        0
};


int
_init(void)
{
        int error;

        error = mod_install(&ssc100_modlinkage);

        if (!error)
                (void) ddi_soft_state_init(&ssc100soft_statep,
                    sizeof (struct ssc100_unit), 1);
        return (error);
}

int
_fini(void)
{
        int error;

        error = mod_remove(&ssc100_modlinkage);
        if (!error)
                ddi_soft_state_fini(&ssc100soft_statep);

        return (error);
}

int
_info(struct modinfo *modinfop)
{
        return (mod_info(&ssc100_modlinkage, modinfop));
}

static int
ssc100_open(dev_t *devp, int flags, int otyp, cred_t *credp)
{
        _NOTE(ARGUNUSED(credp))

        struct ssc100_unit *unitp;
        int instance;
        int error = 0;

        instance = getminor(*devp);

        if (instance < 0) {
                return (ENXIO);
        }

        unitp = (struct ssc100_unit *)
            ddi_get_soft_state(ssc100soft_statep, instance);

        if (unitp == NULL) {
                return (ENXIO);
        }

        if (otyp != OTYP_CHR) {
                return (EINVAL);
        }

        mutex_enter(&unitp->ssc100_mutex);

        if (flags & FEXCL) {
                if (unitp->ssc100_oflag != 0) {
                        error = EBUSY;
                } else {
                        unitp->ssc100_oflag = FEXCL;
                }
        } else {
                if (unitp->ssc100_oflag == FEXCL) {
                        error = EBUSY;
                } else {
                        unitp->ssc100_oflag = FOPEN;
                }
        }

        mutex_exit(&unitp->ssc100_mutex);

        return (error);
}

static int
ssc100_close(dev_t dev, int flags, int otyp, cred_t *credp)
{
        _NOTE(ARGUNUSED(flags, otyp, credp))

        struct ssc100_unit *unitp;
        int instance;

        instance = getminor(dev);

        if (instance < 0) {
                return (ENXIO);
        }
        unitp = (struct ssc100_unit *)
            ddi_get_soft_state(ssc100soft_statep, instance);

        if (unitp == NULL) {
                return (ENXIO);
        }

        mutex_enter(&unitp->ssc100_mutex);

        unitp->ssc100_oflag = 0;

        mutex_exit(&unitp->ssc100_mutex);
        return (DDI_SUCCESS);
}

static int
ssc100_common(struct ssc100_unit *unitp, uchar_t *byte, uchar_t input,
    int8_t flag)
{
        i2c_transfer_t          *i2c_tran_pointer;
        int                     err = I2C_SUCCESS;

        (void) i2c_transfer_alloc(unitp->ssc100_hdl, &i2c_tran_pointer,
            1, 1, I2C_SLEEP);
        if (i2c_tran_pointer == NULL) {
                D2CMN_ERR((CE_WARN, "%s: Failed in SSC100_COMMON "
                    "i2c_tran_pointer not allocated",
                    unitp->ssc100_name));
                return (ENOMEM);
        }

        i2c_tran_pointer->i2c_flags = flag;
        if (flag != I2C_RD) {
                i2c_tran_pointer->i2c_wbuf[0] = input;
        }

        err = i2c_transfer(unitp->ssc100_hdl, i2c_tran_pointer);
        if (err) {
                D2CMN_ERR((CE_WARN, "%s: Failed in SSC100_COMMON "
                    "i2c_transfer routine", unitp->ssc100_name));
        } else if (flag != I2C_WR) {
                *byte = i2c_tran_pointer->i2c_rbuf[0];
        }

        i2c_transfer_free(unitp->ssc100_hdl, i2c_tran_pointer);
        return (err);
}

static int
ssc100_get_reg(struct ssc100_unit *unitp, uchar_t *byte, uchar_t reg)
{
        int                     err = I2C_SUCCESS;

        err = ssc100_common(unitp, byte, reg, I2C_WR_RD);
        if (err) {
                D2CMN_ERR((CE_WARN, "%s: Failed in SSC100_GET_REG "
                    "i2c_common routine", unitp->ssc100_name));
        }
        return (err);
}

static int
ssc100_get(struct ssc100_unit *unitp, uchar_t *byte)
{
        int                     err = I2C_SUCCESS;

        err = ssc100_common(unitp, byte, 0, I2C_RD);
        if (err) {
                D2CMN_ERR((CE_WARN, "%s: Failed in SSC100_GET "
                    "i2c_common routine", unitp->ssc100_name));
        }
        return (err);
}

static int
ssc100_set(struct ssc100_unit *unitp, uchar_t byte)
{
        int                     err = I2C_SUCCESS;

        err = ssc100_common(unitp, NULL, byte, I2C_WR);
        if (err) {
                D2CMN_ERR((CE_WARN, "%s: Failed in SSC100_SET "
                    "i2c_common routine", unitp->ssc100_name));
        }
        return (err);
}

static int
ssc100_ioctl(dev_t dev, int cmd, intptr_t arg, int mode,
    cred_t *credp, int *rvalp)
{
        _NOTE(ARGUNUSED(credp, rvalp))

        struct ssc100_unit      *unitp;
        int             instance;
        int                     err = 0;
        i2c_bit_t               ioctl_bit;
        i2c_port_t              ioctl_port;
        i2c_reg_t ioctl_reg;
        uchar_t                 byte;

        if (arg == (intptr_t)NULL) {
                D2CMN_ERR((CE_WARN, "SSC100: ioctl: arg passed in to ioctl "
                    "= NULL"));
                err = EINVAL;
                return (err);
        }

        instance = getminor(dev);
        unitp = (struct ssc100_unit *)
            ddi_get_soft_state(ssc100soft_statep, instance);
        if (unitp == NULL) {
                cmn_err(CE_WARN, "SSC100: ioctl: unitp not filled");
                return (ENOMEM);
        }

        mutex_enter(&unitp->ssc100_mutex);

        switch (cmd) {
        case I2C_GET_PORT:
                if (ddi_copyin((caddr_t)arg, (caddr_t)&ioctl_port,
                    sizeof (i2c_port_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_GET_PORT"
                            " ddi_copyin routine", unitp->ssc100_name));
                        err = EFAULT;
                        break;
                }

                err = ssc100_get(unitp, &byte);
                if (err != I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_GET_PORT"
                            " ssc100_get routine", unitp->ssc100_name));
                        break;
                }

                ioctl_port.value = byte;
                if (ddi_copyout((caddr_t)&ioctl_port, (caddr_t)arg,
                    sizeof (i2c_port_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in I2C_GET_PORT "
                            "ddi_copyout routine", unitp->ssc100_name));
                        err = EFAULT;
                }

                D1CMN_ERR((CE_NOTE, "%s: contains %x", unitp->ssc100_name,
                    byte));
                break;

        case I2C_SET_PORT:
                if (ddi_copyin((caddr_t)arg, (caddr_t)&ioctl_port,
                    sizeof (uint8_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_PORT"
                            "ddi_cpoyin routine", unitp->ssc100_name));
                        err = EFAULT;
                        break;
                }

                err = ssc100_set(unitp, ioctl_port.value);
                if (err != I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_PORT"
                            " ssc100_set routine", unitp->ssc100_name));
                        break;
                }
                break;

        case I2C_GET_BIT:
                if (ddi_copyin((caddr_t)arg, (caddr_t)&ioctl_bit,
                    sizeof (i2c_bit_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_GET_BIT"
                            " ddi_copyin routine", unitp->ssc100_name));
                        err = EFAULT;
                        break;
                }

                if (ioctl_bit.bit_num > 7) {
                        D2CMN_ERR((CE_WARN, "%s: In I2C_GET_BIT bit num"
                            " was not between 0 and 7",
                            unitp->ssc100_name));
                        err = EIO;
                        break;
                }

                err = ssc100_get(unitp, &byte);
                if (err != I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_GET_BIT"
                            " ssc100_get routine", unitp->ssc100_name));
                        break;
                }

                D1CMN_ERR((CE_NOTE, "%s: byte returned from device is %x",
                    unitp->ssc100_name, byte));
                ioctl_bit.bit_value = (boolean_t)SSC100_BIT_READ_MASK(byte,
                    ioctl_bit.bit_num);
                D1CMN_ERR((CE_NOTE, "%s: byte now contains %x",
                    unitp->ssc100_name, byte));

                if (ddi_copyout((caddr_t)&ioctl_bit, (caddr_t)arg,
                    sizeof (i2c_bit_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in I2C_GET_BIT"
                            " ddi_copyout routine", unitp->ssc100_name));
                        err = EFAULT;
                }
                break;

        case I2C_SET_BIT:
                if (ddi_copyin((caddr_t)arg, (caddr_t)&ioctl_bit,
                    sizeof (i2c_bit_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in I2C_SET_BIT"
                            " ddi_copyin routine", unitp->ssc100_name));
                        err = EFAULT;
                        break;
                }

                if (ioctl_bit.bit_num > 7) {
                        D2CMN_ERR((CE_WARN, "%s: I2C_SET_BIT: bit_num sent"
                            " in was not between 0 and 7",
                            unitp->ssc100_name));
                        err = EIO;
                        break;
                }

                err = ssc100_get(unitp, &byte);
                if (err != I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_BIT"
                            " ssc100_get routine", unitp->ssc100_name));
                        break;
                }

                D1CMN_ERR((CE_NOTE, "%s: byte returned from device is %x",
                    unitp->ssc100_name, byte));
                byte = SSC100_BIT_WRITE_MASK(byte, ioctl_bit.bit_num,
                    ioctl_bit.bit_value);
                D1CMN_ERR((CE_NOTE, "%s: byte after shifting is %x",
                    unitp->ssc100_name, byte));

                err = ssc100_set(unitp, byte);
                if (err != I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_BIT"
                            " ssc100_set routine", unitp->ssc100_name));
                        break;
                }
                break;

        case I2C_GET_REG:
                if (ddi_copyin((caddr_t)arg, (caddr_t)&ioctl_reg,
                    sizeof (i2c_reg_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in I2C_GET_REG "
                            "ddi_copyin routine", unitp->ssc100_name));
                        err = EFAULT;
                        break;
                }

                err = ssc100_get_reg(unitp, &byte, ioctl_reg.reg_num);

                ioctl_reg.reg_value = byte;
                if (ddi_copyout((caddr_t)&ioctl_reg, (caddr_t)arg,
                    sizeof (i2c_reg_t), mode) != DDI_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in I2C_GET_REG "
                            "ddi_copyout routine", unitp->ssc100_name));
                        err = EFAULT;
                }
                break;

        default:
                D2CMN_ERR((CE_WARN, "%s: Invalid IOCTL cmd: %x",
                    unitp->ssc100_name, cmd));
                err = EINVAL;
        }

        mutex_exit(&unitp->ssc100_mutex);
        return (err);
}

static int
ssc100_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
        switch (cmd) {
        case DDI_ATTACH:
                return (ssc100_do_attach(dip));
        case DDI_RESUME:
                return (ssc100_do_resume());
        default:
                return (DDI_FAILURE);
        }
}

static int
ssc100_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
        switch (cmd) {
        case DDI_DETACH:
                return (ssc100_do_detach(dip));
        case DDI_SUSPEND:
                return (ssc100_do_suspend());
        default:
                return (DDI_FAILURE);
        }
}

static int
ssc100_do_attach(dev_info_t *dip)
{
        struct ssc100_unit *unitp;
        int instance;

        instance = ddi_get_instance(dip);

        if (ddi_soft_state_zalloc(ssc100soft_statep, instance) != 0) {
                cmn_err(CE_WARN, "%s%d: failed to zalloc softstate",
                    ddi_get_name(dip), instance);
                return (DDI_FAILURE);
        }

        unitp = ddi_get_soft_state(ssc100soft_statep, instance);

        if (unitp == NULL) {
                cmn_err(CE_WARN, "%s%d: unitp not filled",
                    ddi_get_name(dip), instance);
                return (ENOMEM);
        }

        (void) snprintf(unitp->ssc100_name, sizeof (unitp->ssc100_name),
            "%s%d", ddi_node_name(dip), instance);

        if (ddi_create_minor_node(dip, "ssc100", S_IFCHR, instance,
            "ddi_i2c:ioexp", 0) == DDI_FAILURE) {
                cmn_err(CE_WARN, "%s ddi_create_minor_node failed for "
                    "%s", unitp->ssc100_name, "ssc100");
                ddi_soft_state_free(ssc100soft_statep, instance);

                return (DDI_FAILURE);
        }

        /*
         * If we had different sizes in the future, this could be read
         * from a property.
         */
        unitp->ssc100_size = SSC100_SIZE;

        (void) ddi_prop_create(DDI_DEV_T_NONE, dip,
            DDI_PROP_CANSLEEP, "size",
            (caddr_t)&unitp->ssc100_size, sizeof (unitp->ssc100_size));

        if (i2c_client_register(dip, &unitp->ssc100_hdl) != I2C_SUCCESS) {
                ddi_remove_minor_node(dip, NULL);
                ddi_soft_state_free(ssc100soft_statep, instance);

                return (DDI_FAILURE);
        }

        mutex_init(&unitp->ssc100_mutex, NULL, MUTEX_DRIVER, NULL);

        return (DDI_SUCCESS);
}

static int
ssc100_do_resume()
{
        int ret = DDI_SUCCESS;

        return (ret);
}

static int
ssc100_do_suspend()
{
        int ret = DDI_SUCCESS;

        return (ret);
}

static int
ssc100_do_detach(dev_info_t *dip)
{
        struct ssc100_unit *unitp;
        int instance;

        instance = ddi_get_instance(dip);

        unitp = ddi_get_soft_state(ssc100soft_statep, instance);

        i2c_client_unregister(unitp->ssc100_hdl);

        ddi_remove_minor_node(dip, NULL);

        mutex_destroy(&unitp->ssc100_mutex);

        ddi_soft_state_free(ssc100soft_statep, instance);

        return (DDI_SUCCESS);

}

static int
ssc100_read(dev_t dev, struct uio *uiop, cred_t *cred_p)
{
        _NOTE(ARGUNUSED(cred_p))

        return (ssc100_io(dev, uiop, B_READ));
}

static int
ssc100_write(dev_t dev, struct uio *uiop, cred_t *cred_p)
{
        _NOTE(ARGUNUSED(cred_p))

        return (ssc100_io(dev, uiop, B_WRITE));
}

static int
ssc100_io(dev_t dev, struct uio *uiop, int rw)
{
        struct ssc100_unit *unitp;
        int instance = getminor(dev);
        int     ssc100_addr;
        int     bytes_to_rw;
        int     err = 0;
        int     current_xfer_len;
        i2c_transfer_t *i2ctp = NULL;

        if (instance < 0) {
                return (ENXIO);
        }

        unitp = (struct ssc100_unit *)
            ddi_get_soft_state(ssc100soft_statep, instance);


        if (unitp == NULL) {
                return (ENXIO);
        }

        if (uiop->uio_offset >= unitp->ssc100_size) {
                /*
                 * Exceeded ssc100 size.
                 */
                if (rw == B_WRITE) {

                        return (ENOSPC);
                }
                return (0);
        }

        ssc100_addr = uiop->uio_offset;

        if (uiop->uio_resid == 0) {
                return (0);
        }

        bytes_to_rw = min(uiop->uio_resid,
            unitp->ssc100_size - uiop->uio_offset);
        current_xfer_len = bytes_to_rw;

        if (rw == B_WRITE) {
                (void) i2c_transfer_alloc(unitp->ssc100_hdl, &i2ctp,
                    current_xfer_len+1, 0, I2C_SLEEP);
                if (i2ctp == NULL) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in ssc100_io WRITE "
                            "i2c_tran_pointer not allocated",
                            unitp->ssc100_name));
                        return (ENOMEM);
                }
                i2ctp->i2c_version = I2C_XFER_REV;
                i2ctp->i2c_flags = I2C_WR;
                i2ctp->i2c_wbuf[0] = (uchar_t)ssc100_addr;
                if ((err = uiomove(&i2ctp->i2c_wbuf[1], current_xfer_len,
                    UIO_WRITE, uiop)) != 0) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in ssc100_io WRITE "
                            "uiomove failed", unitp->ssc100_name));
                        goto end;
                }

                if ((err = i2c_transfer(unitp->ssc100_hdl, i2ctp)) !=
                    I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in ssc100_io WRITE "
                            "i2c_transfer failed", unitp->ssc100_name));
                        goto end;
                }
        } else {
                /*
                 * SSC100 read.  We need to first write out the address
                 * that we wish to read.
                 */
                (void) i2c_transfer_alloc(unitp->ssc100_hdl, &i2ctp, 1,
                    current_xfer_len, I2C_SLEEP);
                if (i2ctp == NULL) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in ssc100_io READ "
                            "i2c_tran_pointer not allocated",
                            unitp->ssc100_name));
                        return (ENOMEM);
                }
                i2ctp->i2c_version = I2C_XFER_REV;
                i2ctp->i2c_wbuf[0] = (uchar_t)ssc100_addr;
                i2ctp->i2c_flags = I2C_WR_RD;

                if ((err = i2c_transfer(unitp->ssc100_hdl, i2ctp)) !=
                    I2C_SUCCESS) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in ssc100_io READ "
                            "i2c_transfer failed", unitp->ssc100_name));
                        goto end;
                }

                if ((err = uiomove(i2ctp->i2c_rbuf, current_xfer_len,
                    UIO_READ, uiop)) != 0) {
                        D2CMN_ERR((CE_WARN, "%s: Failed in ssc100_io READ "
                            "uiomove failed", unitp->ssc100_name));
                        goto end;
                }
        }

end:
        i2c_transfer_free(unitp->ssc100_hdl, i2ctp);
        return (err);
}