i2c/clients/pcf8574.c

/*
 * 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/pcf8574_impl.h>

static void *pcf8574soft_statep;

static int pcf8574_do_attach(dev_info_t *);
static int pcf8574_do_detach(dev_info_t *);
static int pcf8574_do_resume(void);
static int pcf8574_do_suspend(void);
static int pcf8574_get(struct pcf8574_unit *, uchar_t *);
static int pcf8574_set(struct pcf8574_unit *, uchar_t);

/*
 * cb ops (only need ioctl)
 */
static int pcf8574_open(dev_t *, int, int, cred_t *);
static int pcf8574_close(dev_t, int, int, cred_t *);
static int pcf8574_ioctl(dev_t, int, intptr_t, int, cred_t *, int *);

static struct cb_ops pcf8574_cbops = {
    pcf8574_open,           /* open  */
    pcf8574_close,          /* close */
    nodev,              /* strategy */
    nodev,              /* print */
    nodev,              /* dump */
    nodev,              /* read */
    nodev,              /* write */
    pcf8574_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 pcf8574_attach(dev_info_t *dip, ddi_attach_cmd_t cmd);
static int pcf8574_detach(dev_info_t *dip, ddi_detach_cmd_t cmd);

static struct dev_ops pcf8574_ops = {
    DEVO_REV,
    0,
    ddi_getinfo_1to1,
    nulldev,
    nulldev,
    pcf8574_attach,
    pcf8574_detach,
    nodev,
    &pcf8574_cbops,
    NULL,           /* bus_ops */
    NULL,           /* power */
    ddi_quiesce_not_needed,     /* quiesce */
};

extern struct mod_ops mod_driverops;

static struct modldrv pcf8574_modldrv = {
    &mod_driverops,         /* type of module - driver */
    "PCF8574 i2c device driver",
    &pcf8574_ops
};

static struct modlinkage pcf8574_modlinkage = {
    MODREV_1,
    &pcf8574_modldrv,
    0
};


int
_init(void)
{
    int error;

    error = mod_install(&pcf8574_modlinkage);

    if (!error)
        (void) ddi_soft_state_init(&pcf8574soft_statep,
            sizeof (struct pcf8574_unit), 1);
    return (error);
}

int
_fini(void)
{
    int error;

    error = mod_remove(&pcf8574_modlinkage);
    if (!error)
        ddi_soft_state_fini(&pcf8574soft_statep);

    return (error);
}

int
_info(struct modinfo *modinfop)
{
    return (mod_info(&pcf8574_modlinkage, modinfop));
}

static int
pcf8574_open(dev_t *devp, int flags, int otyp, cred_t *credp)
{
    _NOTE(ARGUNUSED(credp))

    struct pcf8574_unit *unitp;
    int instance;
    int error = 0;

    D1CMN_ERR((CE_WARN, "Opening the PCF8574 device\n"));

    instance = getminor(*devp);

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

    unitp = (struct pcf8574_unit *)
        ddi_get_soft_state(pcf8574soft_statep, instance);

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

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

    mutex_enter(&unitp->pcf8574_mutex);

    if (flags & FEXCL) {
        if (unitp->pcf8574_oflag != 0) {
            error = EBUSY;
        } else {
            unitp->pcf8574_oflag = FEXCL;
        }
    } else {
        if (unitp->pcf8574_oflag == FEXCL) {
            error = EBUSY;
        } else {
            unitp->pcf8574_oflag = FOPEN;
        }
    }

    mutex_exit(&unitp->pcf8574_mutex);

    return (error);
}

static int
pcf8574_close(dev_t dev, int flags, int otyp, cred_t *credp)
{
    _NOTE(ARGUNUSED(flags, otyp, credp))

    struct pcf8574_unit *unitp;
    int instance;

    instance = getminor(dev);

    if (instance < 0) {
        return (ENXIO);
    }
    unitp = (struct pcf8574_unit *)
        ddi_get_soft_state(pcf8574soft_statep, instance);

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

    mutex_enter(&unitp->pcf8574_mutex);

    unitp->pcf8574_oflag = 0;

    mutex_exit(&unitp->pcf8574_mutex);
    return (DDI_SUCCESS);
}

static int
pcf8574_get(struct pcf8574_unit *unitp, uchar_t *byte) {
    i2c_transfer_t      *i2c_tran_pointer;
    int         err = I2C_SUCCESS;

    D1CMN_ERR((CE_WARN, "Entered the pcf8574_get routine\n"));

    (void) i2c_transfer_alloc(unitp->pcf8574_hdl, &i2c_tran_pointer,
                    0, 1, I2C_SLEEP);
    if (i2c_tran_pointer == NULL) {
        D2CMN_ERR((CE_WARN, "%s: Failed in pcf8574_get "
                "i2c_tran_pointer not allocated\n",
                unitp->pcf8574_name));
        return (ENOMEM);
    }

    i2c_tran_pointer->i2c_flags = I2C_RD;
    err = i2c_transfer(unitp->pcf8574_hdl, i2c_tran_pointer);
    if (err) {
        D2CMN_ERR((CE_WARN, "%s: Failed in the i2c_transfer routine\n",
                unitp->pcf8574_name));
        i2c_transfer_free(unitp->pcf8574_hdl, i2c_tran_pointer);
        return (err);
    }

    D1CMN_ERR((CE_WARN, "Back from a transfer value is %x\n",
        i2c_tran_pointer->i2c_rbuf[0]));
    *byte = i2c_tran_pointer->i2c_rbuf[0];

    i2c_transfer_free(unitp->pcf8574_hdl, i2c_tran_pointer);
    return (err);
}

static int
pcf8574_set(struct pcf8574_unit *unitp, uchar_t byte) {
    i2c_transfer_t      *i2c_tran_pointer;
    int         err = I2C_SUCCESS;

    (void) i2c_transfer_alloc(unitp->pcf8574_hdl, &i2c_tran_pointer,
                1, 0, I2C_SLEEP);
    if (i2c_tran_pointer == NULL) {
        D2CMN_ERR((CE_WARN, "%s: Failed in pcf8574_set "
                "i2c_tran_pointer not allocated\n",
                unitp->pcf8574_name));
        return (ENOMEM);
    }

    i2c_tran_pointer->i2c_flags = I2C_WR;
    i2c_tran_pointer->i2c_wbuf[0] = byte;
    D1CMN_ERR((CE_NOTE, "%s: contains %x\n", unitp->pcf8574_name,
            i2c_tran_pointer->i2c_wbuf[0]));

    err = i2c_transfer(unitp->pcf8574_hdl, i2c_tran_pointer);
    if (err) {
        D2CMN_ERR((CE_WARN, "%s: Failed in the pcf8574_set"
                " i2c_transfer routine\n",
                unitp->pcf8574_name));
        i2c_transfer_free(unitp->pcf8574_hdl, i2c_tran_pointer);
        return (err);
    }
    i2c_transfer_free(unitp->pcf8574_hdl, i2c_tran_pointer);
    return (err);
}

static int
pcf8574_ioctl(dev_t dev, int cmd, intptr_t arg, int mode,
        cred_t *credp, int *rvalp)
{
    _NOTE(ARGUNUSED(credp, rvalp))

    struct pcf8574_unit *unitp;
    int     instance;
    int         err = 0;
    i2c_bit_t       ioctl_bit;
    i2c_port_t      ioctl_port;
    uchar_t         byte;

    if (arg == NULL) {
        D2CMN_ERR((CE_WARN, "PCF8574: ioctl: arg passed in to ioctl "
            "= NULL\n"));
        err = EINVAL;
        return (err);
    }

    instance = getminor(dev);
    unitp = (struct pcf8574_unit *)
        ddi_get_soft_state(pcf8574soft_statep, instance);
    if (unitp == NULL) {
        cmn_err(CE_WARN, "PCF8574: ioctl: unitp not filled\n");
        return (ENOMEM);
    }

    mutex_enter(&unitp->pcf8574_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\n",
                unitp->pcf8574_name));
            err = EFAULT;
            break;
        }

        err = pcf8574_get(unitp, &byte);
        if (err != I2C_SUCCESS) {
            D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_GET_PORT"
                " pcf8574_get routine\n",
                unitp->pcf8574_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\n",
                unitp->pcf8574_name));
            err = EFAULT;
        }

        D1CMN_ERR((CE_NOTE, "%s: contains %x\n", unitp->pcf8574_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\n",
                unitp->pcf8574_name));
            err = EFAULT;
            break;
        }

        err = pcf8574_set(unitp, ioctl_port.value);
        if (err != I2C_SUCCESS) {
            D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_PORT"
                " pcf8574_set routine\n",
                unitp->pcf8574_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\n",
                unitp->pcf8574_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\n",
                unitp->pcf8574_name));
            err = EIO;
            break;
        }

        err = pcf8574_get(unitp, &byte);
        if (err != I2C_SUCCESS) {
            D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_GET_BIT"
                " pcf8574_get routine\n",
                unitp->pcf8574_name));
            break;
        }

        D1CMN_ERR((CE_NOTE, "%s: byte returned from device is %x\n",
            unitp->pcf8574_name, byte));
        ioctl_bit.bit_value = (boolean_t)PCF8574_BIT_READ_MASK(byte,
            ioctl_bit.bit_num);
        D1CMN_ERR((CE_NOTE, "%s: byte now contains %x\n",
            unitp->pcf8574_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\n",
                unitp->pcf8574_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\n",
                unitp->pcf8574_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->pcf8574_name));
            err = EIO;
            break;
        }

        err = pcf8574_get(unitp, &byte);
        if (err != I2C_SUCCESS) {
            D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_BIT"
                " pcf8574_get routine\n",
                unitp->pcf8574_name));
            break;
        }

        D1CMN_ERR((CE_NOTE, "%s: byte returned from device is %x\n",
            unitp->pcf8574_name, byte));
        byte = PCF8574_BIT_WRITE_MASK(byte, ioctl_bit.bit_num,
            ioctl_bit.bit_value);
        D1CMN_ERR((CE_NOTE, "%s: byte after shifting is %x\n",
            unitp->pcf8574_name, byte));

        err = pcf8574_set(unitp, byte);
        if (err != I2C_SUCCESS) {
            D2CMN_ERR((CE_WARN, "%s: Failed in the I2C_SET_BIT"
                " pcf8574_set routine\n",
                unitp->pcf8574_name));
            break;
        }
        break;

    default:
        D2CMN_ERR((CE_WARN, "%s: Invalid IOCTL cmd: %x\n",
            unitp->pcf8574_name, cmd));
        err = EINVAL;
    }

    mutex_exit(&unitp->pcf8574_mutex);
    return (err);
}

static int
pcf8574_attach(dev_info_t *dip, ddi_attach_cmd_t cmd)
{
    switch (cmd) {
    case DDI_ATTACH:
        return (pcf8574_do_attach(dip));
    case DDI_RESUME:
        return (pcf8574_do_resume());
    default:
        return (DDI_FAILURE);
    }
}

static int
pcf8574_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
{
    switch (cmd) {
    case DDI_DETACH:
        return (pcf8574_do_detach(dip));
    case DDI_SUSPEND:
        return (pcf8574_do_suspend());
    default:
        return (DDI_FAILURE);
    }
}

static int
pcf8574_do_attach(dev_info_t *dip)
{
    struct pcf8574_unit *unitp;
    int instance;

    instance = ddi_get_instance(dip);

    if (ddi_soft_state_zalloc(pcf8574soft_statep, instance) != 0) {
        cmn_err(CE_WARN, "%s%d: failed to zalloc softstate\n",
            ddi_get_name(dip), instance);
        return (DDI_FAILURE);
    }

    unitp = ddi_get_soft_state(pcf8574soft_statep, instance);

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

    (void) snprintf(unitp->pcf8574_name, sizeof (unitp->pcf8574_name),
        "%s%d", ddi_node_name(dip), instance);


    if (ddi_create_minor_node(dip, "pcf8574", S_IFCHR, instance,
        "ddi_i2c:ioexp", NULL) == DDI_FAILURE) {
        cmn_err(CE_WARN, "%s ddi_create_minor_node failed for "
            "%s\n", unitp->pcf8574_name, "pcf8574");
        ddi_soft_state_free(pcf8574soft_statep, instance);

        return (DDI_FAILURE);
    }

    if (i2c_client_register(dip, &unitp->pcf8574_hdl) != I2C_SUCCESS) {
        ddi_remove_minor_node(dip, NULL);
        ddi_soft_state_free(pcf8574soft_statep, instance);

        return (DDI_FAILURE);
    }

    mutex_init(&unitp->pcf8574_mutex, NULL, MUTEX_DRIVER, NULL);

    return (DDI_SUCCESS);
}

static int
pcf8574_do_resume()
{
    int ret = DDI_SUCCESS;

    return (ret);
}

static int
pcf8574_do_suspend()
{
    int ret = DDI_SUCCESS;

    return (ret);
}

static int
pcf8574_do_detach(dev_info_t *dip)
{
    struct pcf8574_unit *unitp;
    int instance;

    instance = ddi_get_instance(dip);

    unitp = ddi_get_soft_state(pcf8574soft_statep, instance);

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

    i2c_client_unregister(unitp->pcf8574_hdl);

    ddi_remove_minor_node(dip, NULL);

    mutex_destroy(&unitp->pcf8574_mutex);

    ddi_soft_state_free(pcf8574soft_statep, instance);

    return (DDI_SUCCESS);

}