Commit 61cd1b4c authored by Maciej S. Szmigiero's avatar Maciej S. Szmigiero Committed by Greg Kroah-Hartman

w1: ds2490: USB transfer buffers need to be DMAable

ds2490 driver was doing USB transfers from / to buffers on a stack.
This is not permitted and made the driver non-working with vmapped stacks.

Since all these transfers are done under the same bus_mutex lock we can
simply use shared buffers in a device private structure for two most common
of them.

While we are at it, let's also fix a comparison between int and size_t in
ds9490r_search() which made the driver spin in this function if state
register get requests were failing.
Signed-off-by: default avatarMaciej S. Szmigiero <mail@maciej.szmigiero.name>
Cc: stable <stable@vger.kernel.org>
Acked-by: default avatarEvgeniy Polyakov <zbr@ioremap.net>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 8333eb15
......@@ -153,6 +153,9 @@ struct ds_device
*/
u16 spu_bit;
u8 st_buf[ST_SIZE];
u8 byte_buf;
struct w1_bus_master master;
};
......@@ -174,7 +177,6 @@ struct ds_status
u8 data_in_buffer_status;
u8 reserved1;
u8 reserved2;
};
static struct usb_device_id ds_id_table [] = {
......@@ -244,28 +246,6 @@ static int ds_send_control(struct ds_device *dev, u16 value, u16 index)
return err;
}
static int ds_recv_status_nodump(struct ds_device *dev, struct ds_status *st,
unsigned char *buf, int size)
{
int count, err;
memset(st, 0, sizeof(*st));
count = 0;
err = usb_interrupt_msg(dev->udev, usb_rcvintpipe(dev->udev,
dev->ep[EP_STATUS]), buf, size, &count, 1000);
if (err < 0) {
pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
dev->ep[EP_STATUS], err);
return err;
}
if (count >= sizeof(*st))
memcpy(st, buf, sizeof(*st));
return count;
}
static inline void ds_print_msg(unsigned char *buf, unsigned char *str, int off)
{
pr_info("%45s: %8x\n", str, buf[off]);
......@@ -324,6 +304,35 @@ static void ds_dump_status(struct ds_device *dev, unsigned char *buf, int count)
}
}
static int ds_recv_status(struct ds_device *dev, struct ds_status *st,
bool dump)
{
int count, err;
if (st)
memset(st, 0, sizeof(*st));
count = 0;
err = usb_interrupt_msg(dev->udev,
usb_rcvintpipe(dev->udev,
dev->ep[EP_STATUS]),
dev->st_buf, sizeof(dev->st_buf),
&count, 1000);
if (err < 0) {
pr_err("Failed to read 1-wire data from 0x%x: err=%d.\n",
dev->ep[EP_STATUS], err);
return err;
}
if (dump)
ds_dump_status(dev, dev->st_buf, count);
if (st && count >= sizeof(*st))
memcpy(st, dev->st_buf, sizeof(*st));
return count;
}
static void ds_reset_device(struct ds_device *dev)
{
ds_send_control_cmd(dev, CTL_RESET_DEVICE, 0);
......@@ -344,7 +353,6 @@ static void ds_reset_device(struct ds_device *dev)
static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
{
int count, err;
struct ds_status st;
/* Careful on size. If size is less than what is available in
* the input buffer, the device fails the bulk transfer and
......@@ -359,14 +367,9 @@ static int ds_recv_data(struct ds_device *dev, unsigned char *buf, int size)
err = usb_bulk_msg(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]),
buf, size, &count, 1000);
if (err < 0) {
u8 buf[ST_SIZE];
int count;
pr_info("Clearing ep0x%x.\n", dev->ep[EP_DATA_IN]);
usb_clear_halt(dev->udev, usb_rcvbulkpipe(dev->udev, dev->ep[EP_DATA_IN]));
count = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
ds_dump_status(dev, buf, count);
ds_recv_status(dev, NULL, true);
return err;
}
......@@ -404,7 +407,6 @@ int ds_stop_pulse(struct ds_device *dev, int limit)
{
struct ds_status st;
int count = 0, err = 0;
u8 buf[ST_SIZE];
do {
err = ds_send_control(dev, CTL_HALT_EXE_IDLE, 0);
......@@ -413,7 +415,7 @@ int ds_stop_pulse(struct ds_device *dev, int limit)
err = ds_send_control(dev, CTL_RESUME_EXE, 0);
if (err)
break;
err = ds_recv_status_nodump(dev, &st, buf, sizeof(buf));
err = ds_recv_status(dev, &st, false);
if (err)
break;
......@@ -456,18 +458,17 @@ int ds_detect(struct ds_device *dev, struct ds_status *st)
static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
{
u8 buf[ST_SIZE];
int err, count = 0;
do {
st->status = 0;
err = ds_recv_status_nodump(dev, st, buf, sizeof(buf));
err = ds_recv_status(dev, st, false);
#if 0
if (err >= 0) {
int i;
printk("0x%x: count=%d, status: ", dev->ep[EP_STATUS], err);
for (i=0; i<err; ++i)
printk("%02x ", buf[i]);
printk("%02x ", dev->st_buf[i]);
printk("\n");
}
#endif
......@@ -485,7 +486,7 @@ static int ds_wait_status(struct ds_device *dev, struct ds_status *st)
* can do something with it).
*/
if (err > 16 || count >= 100 || err < 0)
ds_dump_status(dev, buf, err);
ds_dump_status(dev, dev->st_buf, err);
/* Extended data isn't an error. Well, a short is, but the dump
* would have already told the user that and we can't do anything
......@@ -608,7 +609,6 @@ static int ds_write_byte(struct ds_device *dev, u8 byte)
{
int err;
struct ds_status st;
u8 rbyte;
err = ds_send_control(dev, COMM_BYTE_IO | COMM_IM | dev->spu_bit, byte);
if (err)
......@@ -621,11 +621,11 @@ static int ds_write_byte(struct ds_device *dev, u8 byte)
if (err)
return err;
err = ds_recv_data(dev, &rbyte, sizeof(rbyte));
err = ds_recv_data(dev, &dev->byte_buf, 1);
if (err < 0)
return err;
return !(byte == rbyte);
return !(byte == dev->byte_buf);
}
static int ds_read_byte(struct ds_device *dev, u8 *byte)
......@@ -712,7 +712,6 @@ static void ds9490r_search(void *data, struct w1_master *master,
int err;
u16 value, index;
struct ds_status st;
u8 st_buf[ST_SIZE];
int search_limit;
int found = 0;
int i;
......@@ -724,7 +723,12 @@ static void ds9490r_search(void *data, struct w1_master *master,
/* FIFO 128 bytes, bulk packet size 64, read a multiple of the
* packet size.
*/
u64 buf[2*64/8];
const size_t bufsize = 2 * 64;
u64 *buf;
buf = kmalloc(bufsize, GFP_KERNEL);
if (!buf)
return;
mutex_lock(&master->bus_mutex);
......@@ -745,10 +749,9 @@ static void ds9490r_search(void *data, struct w1_master *master,
do {
schedule_timeout(jtime);
if (ds_recv_status_nodump(dev, &st, st_buf, sizeof(st_buf)) <
sizeof(st)) {
err = ds_recv_status(dev, &st, false);
if (err < 0 || err < sizeof(st))
break;
}
if (st.data_in_buffer_status) {
/* Bulk in can receive partial ids, but when it does
......@@ -758,7 +761,7 @@ static void ds9490r_search(void *data, struct w1_master *master,
* bulk without first checking if status says there
* is data to read.
*/
err = ds_recv_data(dev, (u8 *)buf, sizeof(buf));
err = ds_recv_data(dev, (u8 *)buf, bufsize);
if (err < 0)
break;
for (i = 0; i < err/8; ++i) {
......@@ -794,9 +797,14 @@ static void ds9490r_search(void *data, struct w1_master *master,
}
search_out:
mutex_unlock(&master->bus_mutex);
kfree(buf);
}
#if 0
/*
* FIXME: if this disabled code is ever used in the future all ds_send_data()
* calls must be changed to use a DMAable buffer.
*/
static int ds_match_access(struct ds_device *dev, u64 init)
{
int err;
......@@ -845,13 +853,12 @@ static int ds_set_path(struct ds_device *dev, u64 init)
static u8 ds9490r_touch_bit(void *data, u8 bit)
{
u8 ret;
struct ds_device *dev = data;
if (ds_touch_bit(dev, bit, &ret))
if (ds_touch_bit(dev, bit, &dev->byte_buf))
return 0;
return ret;
return dev->byte_buf;
}
#if 0
......@@ -866,13 +873,12 @@ static u8 ds9490r_read_bit(void *data)
{
struct ds_device *dev = data;
int err;
u8 bit = 0;
err = ds_touch_bit(dev, 1, &bit);
err = ds_touch_bit(dev, 1, &dev->byte_buf);
if (err)
return 0;
return bit & 1;
return dev->byte_buf & 1;
}
#endif
......@@ -887,32 +893,52 @@ static u8 ds9490r_read_byte(void *data)
{
struct ds_device *dev = data;
int err;
u8 byte = 0;
err = ds_read_byte(dev, &byte);
err = ds_read_byte(dev, &dev->byte_buf);
if (err)
return 0;
return byte;
return dev->byte_buf;
}
static void ds9490r_write_block(void *data, const u8 *buf, int len)
{
struct ds_device *dev = data;
u8 *tbuf;
if (len <= 0)
return;
tbuf = kmalloc(len, GFP_KERNEL);
if (!tbuf)
return;
ds_write_block(dev, (u8 *)buf, len);
memcpy(tbuf, buf, len);
ds_write_block(dev, tbuf, len);
kfree(tbuf);
}
static u8 ds9490r_read_block(void *data, u8 *buf, int len)
{
struct ds_device *dev = data;
int err;
u8 *tbuf;
err = ds_read_block(dev, buf, len);
if (err < 0)
if (len <= 0)
return 0;
tbuf = kmalloc(len, GFP_KERNEL);
if (!tbuf)
return 0;
return len;
err = ds_read_block(dev, tbuf, len);
if (err >= 0)
memcpy(buf, tbuf, len);
kfree(tbuf);
return err >= 0 ? len : 0;
}
static u8 ds9490r_reset(void *data)
......
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