ipack.c
// SPDX-License-Identifier: GPL-2.0-only
/*
* Industry-pack bus support functions.
*
* Copyright (C) 2011-2012 CERN (www.cern.ch)
* Author: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/idr.h>
#include <linux/io.h>
#include <linux/ipack.h>
#define to_ipack_dev(device) container_of(device, struct ipack_device, dev)
#define to_ipack_driver(drv) container_of(drv, struct ipack_driver, driver)
static DEFINE_IDA(ipack_ida);
static void ipack_device_release(struct device *dev)
{
struct ipack_device *device = to_ipack_dev(dev);
kfree(device->id);
device->release(device);
}
static inline const struct ipack_device_id *
ipack_match_one_device(const struct ipack_device_id *id,
const struct ipack_device *device)
{
if ((id->format == IPACK_ANY_FORMAT ||
id->format == device->id_format) &&
(id->vendor == IPACK_ANY_ID || id->vendor == device->id_vendor) &&
(id->device == IPACK_ANY_ID || id->device == device->id_device))
return id;
return NULL;
}
static const struct ipack_device_id *
ipack_match_id(const struct ipack_device_id *ids, struct ipack_device *idev)
{
if (ids) {
while (ids->vendor || ids->device) {
if (ipack_match_one_device(ids, idev))
return ids;
ids++;
}
}
return NULL;
}
static int ipack_bus_match(struct device *dev, struct device_driver *drv)
{
struct ipack_device *idev = to_ipack_dev(dev);
struct ipack_driver *idrv = to_ipack_driver(drv);
const struct ipack_device_id *found_id;
found_id = ipack_match_id(idrv->id_table, idev);
return found_id ? 1 : 0;
}
static int ipack_bus_probe(struct device *device)
{
struct ipack_device *dev = to_ipack_dev(device);
struct ipack_driver *drv = to_ipack_driver(device->driver);
if (!drv->ops->probe)
return -EINVAL;
return drv->ops->probe(dev);
}
static int ipack_bus_remove(struct device *device)
{
struct ipack_device *dev = to_ipack_dev(device);
struct ipack_driver *drv = to_ipack_driver(device->driver);
if (!drv->ops->remove)
return -EINVAL;
drv->ops->remove(dev);
return 0;
}
static int ipack_uevent(struct device *dev, struct kobj_uevent_env *env)
{
struct ipack_device *idev;
if (!dev)
return -ENODEV;
idev = to_ipack_dev(dev);
if (add_uevent_var(env,
"MODALIAS=ipack:f%02Xv%08Xd%08X", idev->id_format,
idev->id_vendor, idev->id_device))
return -ENOMEM;
return 0;
}
#define ipack_device_attr(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct ipack_device *idev = to_ipack_dev(dev); \
return sprintf(buf, format_string, idev->field); \
}
static ssize_t id_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
unsigned int i, c, l, s;
struct ipack_device *idev = to_ipack_dev(dev);
switch (idev->id_format) {
case IPACK_ID_VERSION_1:
l = 0x7; s = 1; break;
case IPACK_ID_VERSION_2:
l = 0xf; s = 2; break;
default:
return -EIO;
}
c = 0;
for (i = 0; i < idev->id_avail; i++) {
if (i > 0) {
if ((i & l) == 0)
buf[c++] = '\n';
else if ((i & s) == 0)
buf[c++] = ' ';
}
sprintf(&buf[c], "%02x", idev->id[i]);
c += 2;
}
buf[c++] = '\n';
return c;
}
static ssize_t
id_vendor_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct ipack_device *idev = to_ipack_dev(dev);
switch (idev->id_format) {
case IPACK_ID_VERSION_1:
return sprintf(buf, "0x%02x\n", idev->id_vendor);
case IPACK_ID_VERSION_2:
return sprintf(buf, "0x%06x\n", idev->id_vendor);
default:
return -EIO;
}
}
static ssize_t
id_device_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct ipack_device *idev = to_ipack_dev(dev);
switch (idev->id_format) {
case IPACK_ID_VERSION_1:
return sprintf(buf, "0x%02x\n", idev->id_device);
case IPACK_ID_VERSION_2:
return sprintf(buf, "0x%04x\n", idev->id_device);
default:
return -EIO;
}
}
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct ipack_device *idev = to_ipack_dev(dev);
return sprintf(buf, "ipac:f%02Xv%08Xd%08X", idev->id_format,
idev->id_vendor, idev->id_device);
}
ipack_device_attr(id_format, "0x%hhx\n");
static DEVICE_ATTR_RO(id);
static DEVICE_ATTR_RO(id_device);
static DEVICE_ATTR_RO(id_format);
static DEVICE_ATTR_RO(id_vendor);
static DEVICE_ATTR_RO(modalias);
static struct attribute *ipack_attrs[] = {
&dev_attr_id.attr,
&dev_attr_id_device.attr,
&dev_attr_id_format.attr,
&dev_attr_id_vendor.attr,
&dev_attr_modalias.attr,
NULL,
};
ATTRIBUTE_GROUPS(ipack);
static struct bus_type ipack_bus_type = {
.name = "ipack",
.probe = ipack_bus_probe,
.match = ipack_bus_match,
.remove = ipack_bus_remove,
.dev_groups = ipack_groups,
.uevent = ipack_uevent,
};
struct ipack_bus_device *ipack_bus_register(struct device *parent, int slots,
const struct ipack_bus_ops *ops,
struct module *owner)
{
int bus_nr;
struct ipack_bus_device *bus;
bus = kzalloc(sizeof(*bus), GFP_KERNEL);
if (!bus)
return NULL;
bus_nr = ida_simple_get(&ipack_ida, 0, 0, GFP_KERNEL);
if (bus_nr < 0) {
kfree(bus);
return NULL;
}
bus->bus_nr = bus_nr;
bus->parent = parent;
bus->slots = slots;
bus->ops = ops;
bus->owner = owner;
return bus;
}
EXPORT_SYMBOL_GPL(ipack_bus_register);
static int ipack_unregister_bus_member(struct device *dev, void *data)
{
struct ipack_device *idev = to_ipack_dev(dev);
struct ipack_bus_device *bus = data;
if (idev->bus == bus)
ipack_device_del(idev);
return 1;
}
int ipack_bus_unregister(struct ipack_bus_device *bus)
{
bus_for_each_dev(&ipack_bus_type, NULL, bus,
ipack_unregister_bus_member);
ida_simple_remove(&ipack_ida, bus->bus_nr);
kfree(bus);
return 0;
}
EXPORT_SYMBOL_GPL(ipack_bus_unregister);
int ipack_driver_register(struct ipack_driver *edrv, struct module *owner,
const char *name)
{
edrv->driver.owner = owner;
edrv->driver.name = name;
edrv->driver.bus = &ipack_bus_type;
return driver_register(&edrv->driver);
}
EXPORT_SYMBOL_GPL(ipack_driver_register);
void ipack_driver_unregister(struct ipack_driver *edrv)
{
driver_unregister(&edrv->driver);
}
EXPORT_SYMBOL_GPL(ipack_driver_unregister);
static u16 ipack_crc_byte(u16 crc, u8 c)
{
int i;
crc ^= c << 8;
for (i = 0; i < 8; i++)
crc = (crc << 1) ^ ((crc & 0x8000) ? 0x1021 : 0);
return crc;
}
/*
* The algorithm in lib/crc-ccitt.c does not seem to apply since it uses the
* opposite bit ordering.
*/
static u8 ipack_calc_crc1(struct ipack_device *dev)
{
u8 c;
u16 crc;
unsigned int i;
crc = 0xffff;
for (i = 0; i < dev->id_avail; i++) {
c = (i != 11) ? dev->id[i] : 0;
crc = ipack_crc_byte(crc, c);
}
crc = ~crc;
return crc & 0xff;
}
static u16 ipack_calc_crc2(struct ipack_device *dev)
{
u8 c;
u16 crc;
unsigned int i;
crc = 0xffff;
for (i = 0; i < dev->id_avail; i++) {
c = ((i != 0x18) && (i != 0x19)) ? dev->id[i] : 0;
crc = ipack_crc_byte(crc, c);
}
crc = ~crc;
return crc;
}
static void ipack_parse_id1(struct ipack_device *dev)
{
u8 *id = dev->id;
u8 crc;
dev->id_vendor = id[4];
dev->id_device = id[5];
dev->speed_8mhz = 1;
dev->speed_32mhz = (id[7] == 'H');
crc = ipack_calc_crc1(dev);
dev->id_crc_correct = (crc == id[11]);
if (!dev->id_crc_correct) {
dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n",
id[11], crc);
}
}
static void ipack_parse_id2(struct ipack_device *dev)
{
__be16 *id = (__be16 *) dev->id;
u16 flags, crc;
dev->id_vendor = ((be16_to_cpu(id[3]) & 0xff) << 16)
+ be16_to_cpu(id[4]);
dev->id_device = be16_to_cpu(id[5]);
flags = be16_to_cpu(id[10]);
dev->speed_8mhz = !!(flags & 2);
dev->speed_32mhz = !!(flags & 4);
crc = ipack_calc_crc2(dev);
dev->id_crc_correct = (crc == be16_to_cpu(id[12]));
if (!dev->id_crc_correct) {
dev_warn(&dev->dev, "ID CRC invalid found 0x%x, expected 0x%x.\n",
id[11], crc);
}
}
static int ipack_device_read_id(struct ipack_device *dev)
{
u8 __iomem *idmem;
int i;
int ret = 0;
idmem = ioremap(dev->region[IPACK_ID_SPACE].start,
dev->region[IPACK_ID_SPACE].size);
if (!idmem) {
dev_err(&dev->dev, "error mapping memory\n");
return -ENOMEM;
}
/* Determine ID PROM Data Format. If we find the ids "IPAC" or "IPAH"
* we are dealing with a IndustryPack format 1 device. If we detect
* "VITA4 " (16 bit big endian formatted) we are dealing with a
* IndustryPack format 2 device */
if ((ioread8(idmem + 1) == 'I') &&
(ioread8(idmem + 3) == 'P') &&
(ioread8(idmem + 5) == 'A') &&
((ioread8(idmem + 7) == 'C') ||
(ioread8(idmem + 7) == 'H'))) {
dev->id_format = IPACK_ID_VERSION_1;
dev->id_avail = ioread8(idmem + 0x15);
if ((dev->id_avail < 0x0c) || (dev->id_avail > 0x40)) {
dev_warn(&dev->dev, "invalid id size");
dev->id_avail = 0x0c;
}
} else if ((ioread8(idmem + 0) == 'I') &&
(ioread8(idmem + 1) == 'V') &&
(ioread8(idmem + 2) == 'A') &&
(ioread8(idmem + 3) == 'T') &&
(ioread8(idmem + 4) == ' ') &&
(ioread8(idmem + 5) == '4')) {
dev->id_format = IPACK_ID_VERSION_2;
dev->id_avail = ioread16be(idmem + 0x16);
if ((dev->id_avail < 0x1a) || (dev->id_avail > 0x40)) {
dev_warn(&dev->dev, "invalid id size");
dev->id_avail = 0x1a;
}
} else {
dev->id_format = IPACK_ID_VERSION_INVALID;
dev->id_avail = 0;
}
if (!dev->id_avail) {
ret = -ENODEV;
goto out;
}
/* Obtain the amount of memory required to store a copy of the complete
* ID ROM contents */
dev->id = kmalloc(dev->id_avail, GFP_KERNEL);
if (!dev->id) {
ret = -ENOMEM;
goto out;
}
for (i = 0; i < dev->id_avail; i++) {
if (dev->id_format == IPACK_ID_VERSION_1)
dev->id[i] = ioread8(idmem + (i << 1) + 1);
else
dev->id[i] = ioread8(idmem + i);
}
/* now we can finally work with the copy */
switch (dev->id_format) {
case IPACK_ID_VERSION_1:
ipack_parse_id1(dev);
break;
case IPACK_ID_VERSION_2:
ipack_parse_id2(dev);
break;
}
out:
iounmap(idmem);
return ret;
}
int ipack_device_init(struct ipack_device *dev)
{
int ret;
dev->dev.bus = &ipack_bus_type;
dev->dev.release = ipack_device_release;
dev->dev.parent = dev->bus->parent;
dev_set_name(&dev->dev,
"ipack-dev.%u.%u", dev->bus->bus_nr, dev->slot);
device_initialize(&dev->dev);
if (dev->bus->ops->set_clockrate(dev, 8))
dev_warn(&dev->dev, "failed to switch to 8 MHz operation for reading of device ID.\n");
if (dev->bus->ops->reset_timeout(dev))
dev_warn(&dev->dev, "failed to reset potential timeout.");
ret = ipack_device_read_id(dev);
if (ret < 0) {
dev_err(&dev->dev, "error reading device id section.\n");
return ret;
}
/* if the device supports 32 MHz operation, use it. */
if (dev->speed_32mhz) {
ret = dev->bus->ops->set_clockrate(dev, 32);
if (ret < 0)
dev_err(&dev->dev, "failed to switch to 32 MHz operation.\n");
}
return 0;
}
EXPORT_SYMBOL_GPL(ipack_device_init);
int ipack_device_add(struct ipack_device *dev)
{
return device_add(&dev->dev);
}
EXPORT_SYMBOL_GPL(ipack_device_add);
void ipack_device_del(struct ipack_device *dev)
{
device_del(&dev->dev);
ipack_put_device(dev);
}
EXPORT_SYMBOL_GPL(ipack_device_del);
void ipack_get_device(struct ipack_device *dev)
{
get_device(&dev->dev);
}
EXPORT_SYMBOL_GPL(ipack_get_device);
void ipack_put_device(struct ipack_device *dev)
{
put_device(&dev->dev);
}
EXPORT_SYMBOL_GPL(ipack_put_device);
static int __init ipack_init(void)
{
ida_init(&ipack_ida);
return bus_register(&ipack_bus_type);
}
static void __exit ipack_exit(void)
{
bus_unregister(&ipack_bus_type);
ida_destroy(&ipack_ida);
}
module_init(ipack_init);
module_exit(ipack_exit);
MODULE_AUTHOR("Samuel Iglesias Gonsalvez <siglesias@igalia.com>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Industry-pack bus core");