From 627fd1624ef5567fe2d82b7c1282144fa350393e Mon Sep 17 00:00:00 2001 From: Vijay Kumar Banerjee Date: Tue, 25 Jun 2019 12:43:39 +0530 Subject: iicbus: Import from FreeBSD --- freebsd/sys/dev/iicbus/iic.c | 506 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 506 insertions(+) create mode 100644 freebsd/sys/dev/iicbus/iic.c (limited to 'freebsd/sys/dev/iicbus/iic.c') diff --git a/freebsd/sys/dev/iicbus/iic.c b/freebsd/sys/dev/iicbus/iic.c new file mode 100644 index 00000000..dc9c06f9 --- /dev/null +++ b/freebsd/sys/dev/iicbus/iic.c @@ -0,0 +1,506 @@ +#include + +/*- + * SPDX-License-Identifier: BSD-2-Clause-FreeBSD + * + * Copyright (c) 1998, 2001 Nicolas Souchu + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * $FreeBSD$ + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +#include + +struct iic_softc { + device_t sc_dev; + struct cdev *sc_devnode; +}; + +struct iic_cdevpriv { + struct sx lock; + struct iic_softc *sc; + bool started; + uint8_t addr; +}; + + +#define IIC_LOCK(cdp) sx_xlock(&(cdp)->lock) +#define IIC_UNLOCK(cdp) sx_xunlock(&(cdp)->lock) + +static MALLOC_DEFINE(M_IIC, "iic", "I2C device data"); + +static int iic_probe(device_t); +static int iic_attach(device_t); +static int iic_detach(device_t); +static void iic_identify(driver_t *driver, device_t parent); +static void iicdtor(void *data); +static int iicuio_move(struct iic_cdevpriv *priv, struct uio *uio, int last); +static int iicuio(struct cdev *dev, struct uio *uio, int ioflag); +static int iicrdwr(struct iic_cdevpriv *priv, struct iic_rdwr_data *d, int flags); + +static devclass_t iic_devclass; + +static device_method_t iic_methods[] = { + /* device interface */ + DEVMETHOD(device_identify, iic_identify), + DEVMETHOD(device_probe, iic_probe), + DEVMETHOD(device_attach, iic_attach), + DEVMETHOD(device_detach, iic_detach), + + /* iicbus interface */ + DEVMETHOD(iicbus_intr, iicbus_generic_intr), + + { 0, 0 } +}; + +static driver_t iic_driver = { + "iic", + iic_methods, + sizeof(struct iic_softc), +}; + +static d_open_t iicopen; +static d_ioctl_t iicioctl; + +static struct cdevsw iic_cdevsw = { + .d_version = D_VERSION, + .d_open = iicopen, + .d_read = iicuio, + .d_write = iicuio, + .d_ioctl = iicioctl, + .d_name = "iic", +}; + +static void +iic_identify(driver_t *driver, device_t parent) +{ + + if (device_find_child(parent, "iic", -1) == NULL) + BUS_ADD_CHILD(parent, 0, "iic", -1); +} + +static int +iic_probe(device_t dev) +{ + if (iicbus_get_addr(dev) > 0) + return (ENXIO); + + device_set_desc(dev, "I2C generic I/O"); + + return (0); +} + +static int +iic_attach(device_t dev) +{ + struct iic_softc *sc; + + sc = device_get_softc(dev); + sc->sc_dev = dev; + sc->sc_devnode = make_dev(&iic_cdevsw, device_get_unit(dev), + UID_ROOT, GID_WHEEL, + 0600, "iic%d", device_get_unit(dev)); + if (sc->sc_devnode == NULL) { + device_printf(dev, "failed to create character device\n"); + return (ENXIO); + } + sc->sc_devnode->si_drv1 = sc; + + return (0); +} + +static int +iic_detach(device_t dev) +{ + struct iic_softc *sc; + + sc = device_get_softc(dev); + + if (sc->sc_devnode) + destroy_dev(sc->sc_devnode); + + return (0); +} + +static int +iicopen(struct cdev *dev, int flags, int fmt, struct thread *td) +{ + struct iic_cdevpriv *priv; + int error; + + priv = malloc(sizeof(*priv), M_IIC, M_WAITOK | M_ZERO); + + sx_init(&priv->lock, "iic"); + priv->sc = dev->si_drv1; + + error = devfs_set_cdevpriv(priv, iicdtor); + if (error != 0) + free(priv, M_IIC); + + return (error); +} + +static void +iicdtor(void *data) +{ + device_t iicdev, parent; + struct iic_cdevpriv *priv; + + priv = data; + KASSERT(priv != NULL, ("iic cdevpriv should not be NULL!")); + + iicdev = priv->sc->sc_dev; + parent = device_get_parent(iicdev); + + if (priv->started) { + iicbus_stop(parent); + iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); + iicbus_release_bus(parent, iicdev); + } + + sx_destroy(&priv->lock); + free(priv, M_IIC); +} + +static int +iicuio_move(struct iic_cdevpriv *priv, struct uio *uio, int last) +{ + device_t parent; + int error, num_bytes, transferred_bytes, written_bytes; + char buffer[128]; + + parent = device_get_parent(priv->sc->sc_dev); + error = 0; + + /* + * We can only transfer up to sizeof(buffer) bytes in 1 shot, so loop until + * everything has been transferred. + */ + while ((error == 0) && (uio->uio_resid > 0)) { + + num_bytes = MIN(uio->uio_resid, sizeof(buffer)); + transferred_bytes = 0; + + if (uio->uio_rw == UIO_WRITE) { + error = uiomove(buffer, num_bytes, uio); + + while ((error == 0) && (transferred_bytes < num_bytes)) { + written_bytes = 0; + error = iicbus_write(parent, &buffer[transferred_bytes], + num_bytes - transferred_bytes, &written_bytes, 0); + transferred_bytes += written_bytes; + } + + } else if (uio->uio_rw == UIO_READ) { + error = iicbus_read(parent, buffer, + num_bytes, &transferred_bytes, + ((uio->uio_resid <= sizeof(buffer)) ? last : 0), 0); + if (error == 0) + error = uiomove(buffer, transferred_bytes, uio); + } + } + + return (error); +} + +static int +iicuio(struct cdev *dev, struct uio *uio, int ioflag) +{ + device_t parent; + struct iic_cdevpriv *priv; + int error; + uint8_t addr; + + priv = NULL; + error = devfs_get_cdevpriv((void**)&priv); + + if (error != 0) + return (error); + KASSERT(priv != NULL, ("iic cdevpriv should not be NULL!")); + + IIC_LOCK(priv); + if (priv->started || (priv->addr == 0)) { + IIC_UNLOCK(priv); + return (ENXIO); + } + parent = device_get_parent(priv->sc->sc_dev); + + error = iicbus_request_bus(parent, priv->sc->sc_dev, + (ioflag & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); + if (error != 0) { + IIC_UNLOCK(priv); + return (error); + } + + if (uio->uio_rw == UIO_READ) + addr = priv->addr | LSB; + else + addr = priv->addr & ~LSB; + + error = iicbus_start(parent, addr, 0); + if (error != 0) + { + iicbus_release_bus(parent, priv->sc->sc_dev); + IIC_UNLOCK(priv); + return (error); + } + + error = iicuio_move(priv, uio, IIC_LAST_READ); + + iicbus_stop(parent); + iicbus_release_bus(parent, priv->sc->sc_dev); + IIC_UNLOCK(priv); + return (error); +} + +static int +iicrdwr(struct iic_cdevpriv *priv, struct iic_rdwr_data *d, int flags) +{ + struct iic_msg *buf, *m; + void **usrbufs; + device_t iicdev, parent; + int error; + uint32_t i; + + iicdev = priv->sc->sc_dev; + parent = device_get_parent(iicdev); + error = 0; + + if (d->nmsgs > IIC_RDRW_MAX_MSGS) + return (EINVAL); + + buf = malloc(sizeof(*d->msgs) * d->nmsgs, M_IIC, M_WAITOK); + + error = copyin(d->msgs, buf, sizeof(*d->msgs) * d->nmsgs); + if (error != 0) { + free(buf, M_IIC); + return (error); + } + + /* Alloc kernel buffers for userland data, copyin write data */ + usrbufs = malloc(sizeof(void *) * d->nmsgs, M_IIC, M_WAITOK | M_ZERO); + + for (i = 0; i < d->nmsgs; i++) { + m = &(buf[i]); + usrbufs[i] = m->buf; + + /* + * At least init the buffer to NULL so we can safely free() it later. + * If the copyin() to buf failed, don't try to malloc bogus m->len. + */ + m->buf = NULL; + if (error != 0) + continue; + + /* m->len is uint16_t, so allocation size is capped at 64K. */ + m->buf = malloc(m->len, M_IIC, M_WAITOK); + if (!(m->flags & IIC_M_RD)) + error = copyin(usrbufs[i], m->buf, m->len); + } + + if (error == 0) + error = iicbus_request_bus(parent, iicdev, + (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); + + if (error == 0) { + error = iicbus_transfer(iicdev, buf, d->nmsgs); + iicbus_release_bus(parent, iicdev); + } + + /* Copyout all read segments, free up kernel buffers */ + for (i = 0; i < d->nmsgs; i++) { + m = &(buf[i]); + if ((error == 0) && (m->flags & IIC_M_RD)) + error = copyout(m->buf, usrbufs[i], m->len); + free(m->buf, M_IIC); + } + + free(usrbufs, M_IIC); + free(buf, M_IIC); + return (error); +} + +static int +iicioctl(struct cdev *dev, u_long cmd, caddr_t data, int flags, struct thread *td) +{ + device_t parent, iicdev; + struct iiccmd *s; + struct uio ubuf; + struct iovec uvec; + struct iic_cdevpriv *priv; + int error; + + s = (struct iiccmd *)data; + error = devfs_get_cdevpriv((void**)&priv); + if (error != 0) + return (error); + + KASSERT(priv != NULL, ("iic cdevpriv should not be NULL!")); + + iicdev = priv->sc->sc_dev; + parent = device_get_parent(iicdev); + IIC_LOCK(priv); + + + switch (cmd) { + case I2CSTART: + if (priv->started) { + error = EINVAL; + break; + } + error = iicbus_request_bus(parent, iicdev, + (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); + + if (error == 0) + error = iicbus_start(parent, s->slave, 0); + + if (error == 0) { + priv->addr = s->slave; + priv->started = true; + } else + iicbus_release_bus(parent, iicdev); + + break; + + case I2CSTOP: + if (priv->started) { + error = iicbus_stop(parent); + iicbus_release_bus(parent, iicdev); + priv->started = false; + } + + break; + + case I2CRSTCARD: + /* + * Bus should be owned before we reset it. + * We allow the bus to be already owned as the result of an in-progress + * sequence; however, bus reset will always be followed by release + * (a new start is presumably needed for I/O anyway). */ + if (!priv->started) + error = iicbus_request_bus(parent, iicdev, + (flags & O_NONBLOCK) ? IIC_DONTWAIT : (IIC_WAIT | IIC_INTR)); + + if (error == 0) { + error = iicbus_reset(parent, IIC_UNKNOWN, 0, NULL); + /* + * Ignore IIC_ENOADDR as it only means we have a master-only + * controller. + */ + if (error == IIC_ENOADDR) + error = 0; + + iicbus_release_bus(parent, iicdev); + priv->started = false; + } + break; + + case I2CWRITE: + if (!priv->started) { + error = EINVAL; + break; + } + uvec.iov_base = s->buf; + uvec.iov_len = s->count; + ubuf.uio_iov = &uvec; + ubuf.uio_iovcnt = 1; + ubuf.uio_segflg = UIO_USERSPACE; + ubuf.uio_td = td; + ubuf.uio_resid = s->count; + ubuf.uio_offset = 0; + ubuf.uio_rw = UIO_WRITE; + error = iicuio_move(priv, &ubuf, 0); + break; + + case I2CREAD: + if (!priv->started) { + error = EINVAL; + break; + } + uvec.iov_base = s->buf; + uvec.iov_len = s->count; + ubuf.uio_iov = &uvec; + ubuf.uio_iovcnt = 1; + ubuf.uio_segflg = UIO_USERSPACE; + ubuf.uio_td = td; + ubuf.uio_resid = s->count; + ubuf.uio_offset = 0; + ubuf.uio_rw = UIO_READ; + error = iicuio_move(priv, &ubuf, s->last); + break; + + case I2CRDWR: + /* + * The rdwr list should be a self-contained set of + * transactions. Fail if another transaction is in progress. + */ + if (priv->started) { + error = EINVAL; + break; + } + + error = iicrdwr(priv, (struct iic_rdwr_data *)data, flags); + + break; + + case I2CRPTSTART: + if (!priv->started) { + error = EINVAL; + break; + } + error = iicbus_repeated_start(parent, s->slave, 0); + break; + + case I2CSADDR: + priv->addr = *((uint8_t*)data); + break; + + default: + error = ENOTTY; + } + + IIC_UNLOCK(priv); + return (error); +} + +DRIVER_MODULE(iic, iicbus, iic_driver, iic_devclass, 0, 0); +MODULE_DEPEND(iic, iicbus, IICBUS_MINVER, IICBUS_PREFVER, IICBUS_MAXVER); +MODULE_VERSION(iic, 1); -- cgit v1.2.3