![Arnd Bergmann](/assets/img/avatar_default.png)
gcc-7 produces a harmless false-postive warning about a possible NULL pointer access: drivers/memstick/core/memstick.c: In function 'h_memstick_read_dev_id': drivers/memstick/core/memstick.c:309:3: error: argument 2 null where non-null expected [-Werror=nonnull] memcpy(mrq->data, buf, mrq->data_len); This can't happen because the caller sets the command to 'MS_TPC_READ_REG', which causes the data direction to be 'READ' and the NULL pointer not accessed. As a simple workaround for the warning, we can pass a pointer to the data that we actually want to read into. This is not needed here, but also harmless, and lets the compiler know that the access is ok. Link: http://lkml.kernel.org/r/20170111144143.548867-1-arnd@arndb.de Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Alex Dubov <oakad@yahoo.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
655 lines
16 KiB
C
655 lines
16 KiB
C
/*
|
|
* Sony MemoryStick support
|
|
*
|
|
* Copyright (C) 2007 Alex Dubov <oakad@yahoo.com>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*
|
|
* Special thanks to Carlos Corbacho for providing various MemoryStick cards
|
|
* that made this driver possible.
|
|
*
|
|
*/
|
|
|
|
#include <linux/memstick.h>
|
|
#include <linux/idr.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/module.h>
|
|
|
|
#define DRIVER_NAME "memstick"
|
|
|
|
static unsigned int cmd_retries = 3;
|
|
module_param(cmd_retries, uint, 0644);
|
|
|
|
static struct workqueue_struct *workqueue;
|
|
static DEFINE_IDR(memstick_host_idr);
|
|
static DEFINE_SPINLOCK(memstick_host_lock);
|
|
|
|
static int memstick_dev_match(struct memstick_dev *card,
|
|
struct memstick_device_id *id)
|
|
{
|
|
if (id->match_flags & MEMSTICK_MATCH_ALL) {
|
|
if ((id->type == card->id.type)
|
|
&& (id->category == card->id.category)
|
|
&& (id->class == card->id.class))
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int memstick_bus_match(struct device *dev, struct device_driver *drv)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
struct memstick_driver *ms_drv = container_of(drv,
|
|
struct memstick_driver,
|
|
driver);
|
|
struct memstick_device_id *ids = ms_drv->id_table;
|
|
|
|
if (ids) {
|
|
while (ids->match_flags) {
|
|
if (memstick_dev_match(card, ids))
|
|
return 1;
|
|
++ids;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
static int memstick_uevent(struct device *dev, struct kobj_uevent_env *env)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
|
|
if (add_uevent_var(env, "MEMSTICK_TYPE=%02X", card->id.type))
|
|
return -ENOMEM;
|
|
|
|
if (add_uevent_var(env, "MEMSTICK_CATEGORY=%02X", card->id.category))
|
|
return -ENOMEM;
|
|
|
|
if (add_uevent_var(env, "MEMSTICK_CLASS=%02X", card->id.class))
|
|
return -ENOMEM;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int memstick_device_probe(struct device *dev)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
struct memstick_driver *drv = container_of(dev->driver,
|
|
struct memstick_driver,
|
|
driver);
|
|
int rc = -ENODEV;
|
|
|
|
if (dev->driver && drv->probe) {
|
|
rc = drv->probe(card);
|
|
if (!rc)
|
|
get_device(dev);
|
|
}
|
|
return rc;
|
|
}
|
|
|
|
static int memstick_device_remove(struct device *dev)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
struct memstick_driver *drv = container_of(dev->driver,
|
|
struct memstick_driver,
|
|
driver);
|
|
|
|
if (dev->driver && drv->remove) {
|
|
drv->remove(card);
|
|
card->dev.driver = NULL;
|
|
}
|
|
|
|
put_device(dev);
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM
|
|
|
|
static int memstick_device_suspend(struct device *dev, pm_message_t state)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
struct memstick_driver *drv = container_of(dev->driver,
|
|
struct memstick_driver,
|
|
driver);
|
|
|
|
if (dev->driver && drv->suspend)
|
|
return drv->suspend(card, state);
|
|
return 0;
|
|
}
|
|
|
|
static int memstick_device_resume(struct device *dev)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
struct memstick_driver *drv = container_of(dev->driver,
|
|
struct memstick_driver,
|
|
driver);
|
|
|
|
if (dev->driver && drv->resume)
|
|
return drv->resume(card);
|
|
return 0;
|
|
}
|
|
|
|
#else
|
|
|
|
#define memstick_device_suspend NULL
|
|
#define memstick_device_resume NULL
|
|
|
|
#endif /* CONFIG_PM */
|
|
|
|
#define MEMSTICK_ATTR(name, format) \
|
|
static ssize_t name##_show(struct device *dev, struct device_attribute *attr, \
|
|
char *buf) \
|
|
{ \
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev, \
|
|
dev); \
|
|
return sprintf(buf, format, card->id.name); \
|
|
} \
|
|
static DEVICE_ATTR_RO(name);
|
|
|
|
MEMSTICK_ATTR(type, "%02X");
|
|
MEMSTICK_ATTR(category, "%02X");
|
|
MEMSTICK_ATTR(class, "%02X");
|
|
|
|
static struct attribute *memstick_dev_attrs[] = {
|
|
&dev_attr_type.attr,
|
|
&dev_attr_category.attr,
|
|
&dev_attr_class.attr,
|
|
NULL,
|
|
};
|
|
ATTRIBUTE_GROUPS(memstick_dev);
|
|
|
|
static struct bus_type memstick_bus_type = {
|
|
.name = "memstick",
|
|
.dev_groups = memstick_dev_groups,
|
|
.match = memstick_bus_match,
|
|
.uevent = memstick_uevent,
|
|
.probe = memstick_device_probe,
|
|
.remove = memstick_device_remove,
|
|
.suspend = memstick_device_suspend,
|
|
.resume = memstick_device_resume
|
|
};
|
|
|
|
static void memstick_free(struct device *dev)
|
|
{
|
|
struct memstick_host *host = container_of(dev, struct memstick_host,
|
|
dev);
|
|
kfree(host);
|
|
}
|
|
|
|
static struct class memstick_host_class = {
|
|
.name = "memstick_host",
|
|
.dev_release = memstick_free
|
|
};
|
|
|
|
static void memstick_free_card(struct device *dev)
|
|
{
|
|
struct memstick_dev *card = container_of(dev, struct memstick_dev,
|
|
dev);
|
|
kfree(card);
|
|
}
|
|
|
|
static int memstick_dummy_check(struct memstick_dev *card)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
/**
|
|
* memstick_detect_change - schedule media detection on memstick host
|
|
* @host - host to use
|
|
*/
|
|
void memstick_detect_change(struct memstick_host *host)
|
|
{
|
|
queue_work(workqueue, &host->media_checker);
|
|
}
|
|
EXPORT_SYMBOL(memstick_detect_change);
|
|
|
|
/**
|
|
* memstick_next_req - called by host driver to obtain next request to process
|
|
* @host - host to use
|
|
* @mrq - pointer to stick the request to
|
|
*
|
|
* Host calls this function from idle state (*mrq == NULL) or after finishing
|
|
* previous request (*mrq should point to it). If previous request was
|
|
* unsuccessful, it is retried for predetermined number of times. Return value
|
|
* of 0 means that new request was assigned to the host.
|
|
*/
|
|
int memstick_next_req(struct memstick_host *host, struct memstick_request **mrq)
|
|
{
|
|
int rc = -ENXIO;
|
|
|
|
if ((*mrq) && (*mrq)->error && host->retries) {
|
|
(*mrq)->error = rc;
|
|
host->retries--;
|
|
return 0;
|
|
}
|
|
|
|
if (host->card && host->card->next_request)
|
|
rc = host->card->next_request(host->card, mrq);
|
|
|
|
if (!rc)
|
|
host->retries = cmd_retries > 1 ? cmd_retries - 1 : 1;
|
|
else
|
|
*mrq = NULL;
|
|
|
|
return rc;
|
|
}
|
|
EXPORT_SYMBOL(memstick_next_req);
|
|
|
|
/**
|
|
* memstick_new_req - notify the host that some requests are pending
|
|
* @host - host to use
|
|
*/
|
|
void memstick_new_req(struct memstick_host *host)
|
|
{
|
|
if (host->card) {
|
|
host->retries = cmd_retries;
|
|
reinit_completion(&host->card->mrq_complete);
|
|
host->request(host);
|
|
}
|
|
}
|
|
EXPORT_SYMBOL(memstick_new_req);
|
|
|
|
/**
|
|
* memstick_init_req_sg - set request fields needed for bulk data transfer
|
|
* @mrq - request to use
|
|
* @tpc - memstick Transport Protocol Command
|
|
* @sg - TPC argument
|
|
*/
|
|
void memstick_init_req_sg(struct memstick_request *mrq, unsigned char tpc,
|
|
const struct scatterlist *sg)
|
|
{
|
|
mrq->tpc = tpc;
|
|
if (tpc & 8)
|
|
mrq->data_dir = WRITE;
|
|
else
|
|
mrq->data_dir = READ;
|
|
|
|
mrq->sg = *sg;
|
|
mrq->long_data = 1;
|
|
|
|
if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
|
|
mrq->need_card_int = 1;
|
|
else
|
|
mrq->need_card_int = 0;
|
|
}
|
|
EXPORT_SYMBOL(memstick_init_req_sg);
|
|
|
|
/**
|
|
* memstick_init_req - set request fields needed for short data transfer
|
|
* @mrq - request to use
|
|
* @tpc - memstick Transport Protocol Command
|
|
* @buf - TPC argument buffer
|
|
* @length - TPC argument size
|
|
*
|
|
* The intended use of this function (transfer of data items several bytes
|
|
* in size) allows us to just copy the value between request structure and
|
|
* user supplied buffer.
|
|
*/
|
|
void memstick_init_req(struct memstick_request *mrq, unsigned char tpc,
|
|
const void *buf, size_t length)
|
|
{
|
|
mrq->tpc = tpc;
|
|
if (tpc & 8)
|
|
mrq->data_dir = WRITE;
|
|
else
|
|
mrq->data_dir = READ;
|
|
|
|
mrq->data_len = length > sizeof(mrq->data) ? sizeof(mrq->data) : length;
|
|
if (mrq->data_dir == WRITE)
|
|
memcpy(mrq->data, buf, mrq->data_len);
|
|
|
|
mrq->long_data = 0;
|
|
|
|
if (tpc == MS_TPC_SET_CMD || tpc == MS_TPC_EX_SET_CMD)
|
|
mrq->need_card_int = 1;
|
|
else
|
|
mrq->need_card_int = 0;
|
|
}
|
|
EXPORT_SYMBOL(memstick_init_req);
|
|
|
|
/*
|
|
* Functions prefixed with "h_" are protocol callbacks. They can be called from
|
|
* interrupt context. Return value of 0 means that request processing is still
|
|
* ongoing, while special error value of -EAGAIN means that current request is
|
|
* finished (and request processor should come back some time later).
|
|
*/
|
|
|
|
static int h_memstick_read_dev_id(struct memstick_dev *card,
|
|
struct memstick_request **mrq)
|
|
{
|
|
struct ms_id_register id_reg;
|
|
|
|
if (!(*mrq)) {
|
|
memstick_init_req(&card->current_mrq, MS_TPC_READ_REG, &id_reg,
|
|
sizeof(struct ms_id_register));
|
|
*mrq = &card->current_mrq;
|
|
return 0;
|
|
} else {
|
|
if (!(*mrq)->error) {
|
|
memcpy(&id_reg, (*mrq)->data, sizeof(id_reg));
|
|
card->id.match_flags = MEMSTICK_MATCH_ALL;
|
|
card->id.type = id_reg.type;
|
|
card->id.category = id_reg.category;
|
|
card->id.class = id_reg.class;
|
|
dev_dbg(&card->dev, "if_mode = %02x\n", id_reg.if_mode);
|
|
}
|
|
complete(&card->mrq_complete);
|
|
return -EAGAIN;
|
|
}
|
|
}
|
|
|
|
static int h_memstick_set_rw_addr(struct memstick_dev *card,
|
|
struct memstick_request **mrq)
|
|
{
|
|
if (!(*mrq)) {
|
|
memstick_init_req(&card->current_mrq, MS_TPC_SET_RW_REG_ADRS,
|
|
(char *)&card->reg_addr,
|
|
sizeof(card->reg_addr));
|
|
*mrq = &card->current_mrq;
|
|
return 0;
|
|
} else {
|
|
complete(&card->mrq_complete);
|
|
return -EAGAIN;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* memstick_set_rw_addr - issue SET_RW_REG_ADDR request and wait for it to
|
|
* complete
|
|
* @card - media device to use
|
|
*/
|
|
int memstick_set_rw_addr(struct memstick_dev *card)
|
|
{
|
|
card->next_request = h_memstick_set_rw_addr;
|
|
memstick_new_req(card->host);
|
|
wait_for_completion(&card->mrq_complete);
|
|
|
|
return card->current_mrq.error;
|
|
}
|
|
EXPORT_SYMBOL(memstick_set_rw_addr);
|
|
|
|
static struct memstick_dev *memstick_alloc_card(struct memstick_host *host)
|
|
{
|
|
struct memstick_dev *card = kzalloc(sizeof(struct memstick_dev),
|
|
GFP_KERNEL);
|
|
struct memstick_dev *old_card = host->card;
|
|
struct ms_id_register id_reg;
|
|
|
|
if (card) {
|
|
card->host = host;
|
|
dev_set_name(&card->dev, "%s", dev_name(&host->dev));
|
|
card->dev.parent = &host->dev;
|
|
card->dev.bus = &memstick_bus_type;
|
|
card->dev.release = memstick_free_card;
|
|
card->check = memstick_dummy_check;
|
|
|
|
card->reg_addr.r_offset = offsetof(struct ms_register, id);
|
|
card->reg_addr.r_length = sizeof(id_reg);
|
|
card->reg_addr.w_offset = offsetof(struct ms_register, id);
|
|
card->reg_addr.w_length = sizeof(id_reg);
|
|
|
|
init_completion(&card->mrq_complete);
|
|
|
|
host->card = card;
|
|
if (memstick_set_rw_addr(card))
|
|
goto err_out;
|
|
|
|
card->next_request = h_memstick_read_dev_id;
|
|
memstick_new_req(host);
|
|
wait_for_completion(&card->mrq_complete);
|
|
|
|
if (card->current_mrq.error)
|
|
goto err_out;
|
|
}
|
|
host->card = old_card;
|
|
return card;
|
|
err_out:
|
|
host->card = old_card;
|
|
kfree(card);
|
|
return NULL;
|
|
}
|
|
|
|
static int memstick_power_on(struct memstick_host *host)
|
|
{
|
|
int rc = host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_ON);
|
|
|
|
if (!rc)
|
|
rc = host->set_param(host, MEMSTICK_INTERFACE, MEMSTICK_SERIAL);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void memstick_check(struct work_struct *work)
|
|
{
|
|
struct memstick_host *host = container_of(work, struct memstick_host,
|
|
media_checker);
|
|
struct memstick_dev *card;
|
|
|
|
dev_dbg(&host->dev, "memstick_check started\n");
|
|
mutex_lock(&host->lock);
|
|
if (!host->card) {
|
|
if (memstick_power_on(host))
|
|
goto out_power_off;
|
|
} else if (host->card->stop)
|
|
host->card->stop(host->card);
|
|
|
|
card = memstick_alloc_card(host);
|
|
|
|
if (!card) {
|
|
if (host->card) {
|
|
device_unregister(&host->card->dev);
|
|
host->card = NULL;
|
|
}
|
|
} else {
|
|
dev_dbg(&host->dev, "new card %02x, %02x, %02x\n",
|
|
card->id.type, card->id.category, card->id.class);
|
|
if (host->card) {
|
|
if (memstick_set_rw_addr(host->card)
|
|
|| !memstick_dev_match(host->card, &card->id)
|
|
|| !(host->card->check(host->card))) {
|
|
device_unregister(&host->card->dev);
|
|
host->card = NULL;
|
|
} else if (host->card->start)
|
|
host->card->start(host->card);
|
|
}
|
|
|
|
if (!host->card) {
|
|
host->card = card;
|
|
if (device_register(&card->dev)) {
|
|
put_device(&card->dev);
|
|
kfree(host->card);
|
|
host->card = NULL;
|
|
}
|
|
} else
|
|
kfree(card);
|
|
}
|
|
|
|
out_power_off:
|
|
if (!host->card)
|
|
host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
|
|
|
|
mutex_unlock(&host->lock);
|
|
dev_dbg(&host->dev, "memstick_check finished\n");
|
|
}
|
|
|
|
/**
|
|
* memstick_alloc_host - allocate a memstick_host structure
|
|
* @extra: size of the user private data to allocate
|
|
* @dev: parent device of the host
|
|
*/
|
|
struct memstick_host *memstick_alloc_host(unsigned int extra,
|
|
struct device *dev)
|
|
{
|
|
struct memstick_host *host;
|
|
|
|
host = kzalloc(sizeof(struct memstick_host) + extra, GFP_KERNEL);
|
|
if (host) {
|
|
mutex_init(&host->lock);
|
|
INIT_WORK(&host->media_checker, memstick_check);
|
|
host->dev.class = &memstick_host_class;
|
|
host->dev.parent = dev;
|
|
device_initialize(&host->dev);
|
|
}
|
|
return host;
|
|
}
|
|
EXPORT_SYMBOL(memstick_alloc_host);
|
|
|
|
/**
|
|
* memstick_add_host - start request processing on memstick host
|
|
* @host - host to use
|
|
*/
|
|
int memstick_add_host(struct memstick_host *host)
|
|
{
|
|
int rc;
|
|
|
|
idr_preload(GFP_KERNEL);
|
|
spin_lock(&memstick_host_lock);
|
|
|
|
rc = idr_alloc(&memstick_host_idr, host, 0, 0, GFP_NOWAIT);
|
|
if (rc >= 0)
|
|
host->id = rc;
|
|
|
|
spin_unlock(&memstick_host_lock);
|
|
idr_preload_end();
|
|
if (rc < 0)
|
|
return rc;
|
|
|
|
dev_set_name(&host->dev, "memstick%u", host->id);
|
|
|
|
rc = device_add(&host->dev);
|
|
if (rc) {
|
|
spin_lock(&memstick_host_lock);
|
|
idr_remove(&memstick_host_idr, host->id);
|
|
spin_unlock(&memstick_host_lock);
|
|
return rc;
|
|
}
|
|
|
|
host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
|
|
memstick_detect_change(host);
|
|
return 0;
|
|
}
|
|
EXPORT_SYMBOL(memstick_add_host);
|
|
|
|
/**
|
|
* memstick_remove_host - stop request processing on memstick host
|
|
* @host - host to use
|
|
*/
|
|
void memstick_remove_host(struct memstick_host *host)
|
|
{
|
|
flush_workqueue(workqueue);
|
|
mutex_lock(&host->lock);
|
|
if (host->card)
|
|
device_unregister(&host->card->dev);
|
|
host->card = NULL;
|
|
host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
|
|
mutex_unlock(&host->lock);
|
|
|
|
spin_lock(&memstick_host_lock);
|
|
idr_remove(&memstick_host_idr, host->id);
|
|
spin_unlock(&memstick_host_lock);
|
|
device_del(&host->dev);
|
|
}
|
|
EXPORT_SYMBOL(memstick_remove_host);
|
|
|
|
/**
|
|
* memstick_free_host - free memstick host
|
|
* @host - host to use
|
|
*/
|
|
void memstick_free_host(struct memstick_host *host)
|
|
{
|
|
mutex_destroy(&host->lock);
|
|
put_device(&host->dev);
|
|
}
|
|
EXPORT_SYMBOL(memstick_free_host);
|
|
|
|
/**
|
|
* memstick_suspend_host - notify bus driver of host suspension
|
|
* @host - host to use
|
|
*/
|
|
void memstick_suspend_host(struct memstick_host *host)
|
|
{
|
|
mutex_lock(&host->lock);
|
|
host->set_param(host, MEMSTICK_POWER, MEMSTICK_POWER_OFF);
|
|
mutex_unlock(&host->lock);
|
|
}
|
|
EXPORT_SYMBOL(memstick_suspend_host);
|
|
|
|
/**
|
|
* memstick_resume_host - notify bus driver of host resumption
|
|
* @host - host to use
|
|
*/
|
|
void memstick_resume_host(struct memstick_host *host)
|
|
{
|
|
int rc = 0;
|
|
|
|
mutex_lock(&host->lock);
|
|
if (host->card)
|
|
rc = memstick_power_on(host);
|
|
mutex_unlock(&host->lock);
|
|
|
|
if (!rc)
|
|
memstick_detect_change(host);
|
|
}
|
|
EXPORT_SYMBOL(memstick_resume_host);
|
|
|
|
int memstick_register_driver(struct memstick_driver *drv)
|
|
{
|
|
drv->driver.bus = &memstick_bus_type;
|
|
|
|
return driver_register(&drv->driver);
|
|
}
|
|
EXPORT_SYMBOL(memstick_register_driver);
|
|
|
|
void memstick_unregister_driver(struct memstick_driver *drv)
|
|
{
|
|
driver_unregister(&drv->driver);
|
|
}
|
|
EXPORT_SYMBOL(memstick_unregister_driver);
|
|
|
|
|
|
static int __init memstick_init(void)
|
|
{
|
|
int rc;
|
|
|
|
workqueue = create_freezable_workqueue("kmemstick");
|
|
if (!workqueue)
|
|
return -ENOMEM;
|
|
|
|
rc = bus_register(&memstick_bus_type);
|
|
if (!rc)
|
|
rc = class_register(&memstick_host_class);
|
|
|
|
if (!rc)
|
|
return 0;
|
|
|
|
bus_unregister(&memstick_bus_type);
|
|
destroy_workqueue(workqueue);
|
|
|
|
return rc;
|
|
}
|
|
|
|
static void __exit memstick_exit(void)
|
|
{
|
|
class_unregister(&memstick_host_class);
|
|
bus_unregister(&memstick_bus_type);
|
|
destroy_workqueue(workqueue);
|
|
idr_destroy(&memstick_host_idr);
|
|
}
|
|
|
|
module_init(memstick_init);
|
|
module_exit(memstick_exit);
|
|
|
|
MODULE_AUTHOR("Alex Dubov");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_DESCRIPTION("Sony MemoryStick core driver");
|