freebsd-skq/sys/dev/ichiic/ig4_pci.c
Michael Gmelin 4cd6abddcd Protect smbus ioctls in ig4 driver using a shared lock.
Document locking semantics.

Differential Revision:	https://reviews.freebsd.org/D2744
Reviewed by:	jah, kib
Approved by:	kib
2015-06-25 07:52:51 +00:00

198 lines
5.5 KiB
C

/*
* Copyright (c) 2014 The DragonFly Project. All rights reserved.
*
* This code is derived from software contributed to The DragonFly Project
* by Matthew Dillon <dillon@backplane.com> and was subsequently ported
* to FreeBSD by Michael Gmelin <freebsd@grem.de>
*
* 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.
* 3. Neither the name of The DragonFly Project nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific, prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
* COPYRIGHT HOLDERS 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Intel fourth generation mobile cpus integrated I2C device, smbus driver.
*
* See ig4_reg.h for datasheet reference and notes.
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/errno.h>
#include <sys/lock.h>
#include <sys/mutex.h>
#include <sys/sx.h>
#include <sys/syslog.h>
#include <sys/bus.h>
#include <machine/bus.h>
#include <sys/rman.h>
#include <machine/resource.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/smbus/smbconf.h>
#include "smbus_if.h"
#include <dev/ichiic/ig4_reg.h>
#include <dev/ichiic/ig4_var.h>
static int ig4iic_pci_detach(device_t dev);
#define PCI_CHIP_LYNXPT_LP_I2C_1 0x9c618086
#define PCI_CHIP_LYNXPT_LP_I2C_2 0x9c628086
static int
ig4iic_pci_probe(device_t dev)
{
switch(pci_get_devid(dev)) {
case PCI_CHIP_LYNXPT_LP_I2C_1:
device_set_desc(dev, "Intel Lynx Point-LP I2C Controller-1");
break;
case PCI_CHIP_LYNXPT_LP_I2C_2:
device_set_desc(dev, "Intel Lynx Point-LP I2C Controller-2");
break;
default:
return (ENXIO);
}
return (BUS_PROBE_DEFAULT);
}
static int
ig4iic_pci_attach(device_t dev)
{
ig4iic_softc_t *sc = device_get_softc(dev);
int error;
bzero(sc, sizeof(*sc));
mtx_init(&sc->io_lock, "IG4 I/O lock", NULL, MTX_DEF);
sx_init(&sc->call_lock, "IG4 call lock");
sc->dev = dev;
sc->regs_rid = PCIR_BAR(0);
sc->regs_res = bus_alloc_resource_any(dev, SYS_RES_MEMORY,
&sc->regs_rid, RF_ACTIVE);
if (sc->regs_res == NULL) {
device_printf(dev, "unable to map registers\n");
ig4iic_pci_detach(dev);
return (ENXIO);
}
sc->intr_rid = 0;
if (pci_alloc_msi(dev, &sc->intr_rid)) {
device_printf(dev, "Using MSI\n");
}
sc->intr_res = bus_alloc_resource_any(dev, SYS_RES_IRQ,
&sc->intr_rid, RF_SHAREABLE | RF_ACTIVE);
if (sc->intr_res == NULL) {
device_printf(dev, "unable to map interrupt\n");
ig4iic_pci_detach(dev);
return (ENXIO);
}
sc->pci_attached = 1;
error = ig4iic_attach(sc);
if (error)
ig4iic_pci_detach(dev);
return (error);
}
static int
ig4iic_pci_detach(device_t dev)
{
ig4iic_softc_t *sc = device_get_softc(dev);
int error;
if (sc->pci_attached) {
error = ig4iic_detach(sc);
if (error)
return (error);
sc->pci_attached = 0;
}
if (sc->intr_res) {
bus_release_resource(dev, SYS_RES_IRQ,
sc->intr_rid, sc->intr_res);
sc->intr_res = NULL;
}
if (sc->intr_rid != 0)
pci_release_msi(dev);
if (sc->regs_res) {
bus_release_resource(dev, SYS_RES_MEMORY,
sc->regs_rid, sc->regs_res);
sc->regs_res = NULL;
}
if (mtx_initialized(&sc->io_lock)) {
mtx_destroy(&sc->io_lock);
sx_destroy(&sc->call_lock);
}
return (0);
}
static device_method_t ig4iic_pci_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, ig4iic_pci_probe),
DEVMETHOD(device_attach, ig4iic_pci_attach),
DEVMETHOD(device_detach, ig4iic_pci_detach),
/* SMBus methods from ig4_smb.c */
DEVMETHOD(smbus_callback, ig4iic_smb_callback),
DEVMETHOD(smbus_quick, ig4iic_smb_quick),
DEVMETHOD(smbus_sendb, ig4iic_smb_sendb),
DEVMETHOD(smbus_recvb, ig4iic_smb_recvb),
DEVMETHOD(smbus_writeb, ig4iic_smb_writeb),
DEVMETHOD(smbus_writew, ig4iic_smb_writew),
DEVMETHOD(smbus_readb, ig4iic_smb_readb),
DEVMETHOD(smbus_readw, ig4iic_smb_readw),
DEVMETHOD(smbus_pcall, ig4iic_smb_pcall),
DEVMETHOD(smbus_bwrite, ig4iic_smb_bwrite),
DEVMETHOD(smbus_bread, ig4iic_smb_bread),
DEVMETHOD(smbus_trans, ig4iic_smb_trans),
DEVMETHOD_END
};
static driver_t ig4iic_pci_driver = {
"ig4iic",
ig4iic_pci_methods,
sizeof(struct ig4iic_softc)
};
static devclass_t ig4iic_pci_devclass;
DRIVER_MODULE(ig4iic, pci, ig4iic_pci_driver, ig4iic_pci_devclass, 0, 0);
MODULE_DEPEND(ig4iic, pci, 1, 1, 1);
MODULE_DEPEND(ig4iic, smbus, SMBUS_MINVER, SMBUS_PREFVER, SMBUS_MAXVER);
MODULE_VERSION(ig4iic, 1);