From d28d57629ffcd30e11a6085e15ee1327fea60b60 Mon Sep 17 00:00:00 2001
From: Manu Abraham <manu@linuxtv.org>
Date: Tue, 8 Nov 2005 21:35:36 -0800
Subject: [PATCH] [PATCH] dvb: dst: protect the read/write commands with a
mutex
We need to protect the read/write commands with a mutex.
Bug reported by Henrik Sjoberg <henke@epact.se>
Signed-off-by: Manu Abraham <manu@linuxtv.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Cc: Johannes Stezenbach <js@linuxtv.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
drivers/media/dvb/bt8xx/dst.c | 34 +++++++++++++++++-----------
drivers/media/dvb/bt8xx/dst_ca.c | 17 +++++++++-----
drivers/media/dvb/bt8xx/dst_common.h | 3 +++
3 files changed, 35 insertions(+), 19 deletions(-)
diff --git a/drivers/media/dvb/bt8xx/dst.c b/drivers/media/dvb/bt8xx/dst.c
index bc833a55438f..0c718dca09ca 100644
--- a/drivers/media/dvb/bt8xx/dst.c
+++ b/drivers/media/dvb/bt8xx/dst.c
@@ -910,6 +910,7 @@ static int dst_get_device_id(struct dst_state *state)
static int dst_probe(struct dst_state *state)
{
+ sema_init(&state->dst_mutex, 1);
if ((rdc_8820_reset(state)) < 0) {
dprintk(verbose, DST_ERROR, 1, "RDC 8820 RESET Failed.");
return -1;
@@ -960,21 +961,23 @@ static int dst_probe(struct dst_state *state)
int dst_command(struct dst_state *state, u8 *data, u8 len)
{
u8 reply;
+
+ down(&state->dst_mutex);
if ((dst_comm_init(state)) < 0) {
dprintk(verbose, DST_NOTICE, 1, "DST Communication Initialization Failed.");
- return -1;
+ goto error;
}
if (write_dst(state, data, len)) {
dprintk(verbose, DST_INFO, 1, "Tring to recover.. ");
if ((dst_error_recovery(state)) < 0) {
dprintk(verbose, DST_ERROR, 1, "Recovery Failed.");
- return -1;
+ goto error;
}
- return -1;
+ goto error;
}
if ((dst_pio_disable(state)) < 0) {
dprintk(verbose, DST_ERROR, 1, "PIO Disable Failed.");
- return -1;
+ goto error;
}
if (state->type_flags & DST_TYPE_HAS_FW_1)
udelay(3000);
@@ -982,36 +985,41 @@ int dst_command(struct dst_state *state, u8 *data, u8 len)
dprintk(verbose, DST_DEBUG, 1, "Trying to recover.. ");
if ((dst_error_recovery(state)) < 0) {
dprintk(verbose, DST_INFO, 1, "Recovery Failed.");
- return -1;
+ goto error;
}
- return -1;
+ goto error;
}
if (reply != ACK) {
dprintk(verbose, DST_INFO, 1, "write not acknowledged 0x%02x ", reply);
- return -1;
+ goto error;
}
if (len >= 2 && data[0] == 0 && (data[1] == 1 || data[1] == 3))
- return 0;
+ goto error;
if (state->type_flags & DST_TYPE_HAS_FW_1)
udelay(3000);
else
udelay(2000);
if (!dst_wait_dst_ready(state, NO_DELAY))
- return -1;
+ goto error;
if (read_dst(state, state->rxbuffer, FIXED_COMM)) {
dprintk(verbose, DST_DEBUG, 1, "Trying to recover.. ");
if ((dst_error_recovery(state)) < 0) {
dprintk(verbose, DST_INFO, 1, "Recovery failed.");
- return -1;
+ goto error;
}
- return -1;
+ goto error;
}
if (state->rxbuffer[7] != dst_check_sum(state->rxbuffer, 7)) {
dprintk(verbose, DST_INFO, 1, "checksum failure");
- return -1;
+ goto error;
}
-
+ up(&state->dst_mutex);
return 0;
+
+error:
+ up(&state->dst_mutex);
+ return -EIO;
+
}
EXPORT_SYMBOL(dst_command);
diff --git a/drivers/media/dvb/bt8xx/dst_ca.c b/drivers/media/dvb/bt8xx/dst_ca.c
index 38c728945bf1..e6541aff3996 100644
--- a/drivers/media/dvb/bt8xx/dst_ca.c
+++ b/drivers/media/dvb/bt8xx/dst_ca.c
@@ -81,36 +81,41 @@ static int dst_ci_command(struct dst_state* state, u8 * data, u8 *ca_string, u8
{
u8 reply;
+ down(&state->dst_mutex);
dst_comm_init(state);
msleep(65);
if (write_dst(state, data, len)) {
dprintk(verbose, DST_CA_INFO, 1, " Write not successful, trying to recover");
dst_error_recovery(state);
- return -1;
+ goto error;
}
if ((dst_pio_disable(state)) < 0) {
dprintk(verbose, DST_CA_ERROR, 1, " DST PIO disable failed.");
- return -1;
+ goto error;
}
if (read_dst(state, &reply, GET_ACK) < 0) {
dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");
dst_error_recovery(state);
- return -1;
+ goto error;
}
if (read) {
if (! dst_wait_dst_ready(state, LONG_DELAY)) {
dprintk(verbose, DST_CA_NOTICE, 1, " 8820 not ready");
- return -1;
+ goto error;
}
if (read_dst(state, ca_string, 128) < 0) { /* Try to make this dynamic */
dprintk(verbose, DST_CA_INFO, 1, " Read not successful, trying to recover");
dst_error_recovery(state);
- return -1;
+ goto error;
}
}
-
+ up(&state->dst_mutex);
return 0;
+
+error:
+ up(&state->dst_mutex);
+ return -EIO;
}
diff --git a/drivers/media/dvb/bt8xx/dst_common.h b/drivers/media/dvb/bt8xx/dst_common.h
index 29b5430dbe4f..81557f38fe38 100644
--- a/drivers/media/dvb/bt8xx/dst_common.h
+++ b/drivers/media/dvb/bt8xx/dst_common.h
@@ -22,6 +22,7 @@
#ifndef DST_COMMON_H
#define DST_COMMON_H
+#include <linux/smp_lock.h>
#include <linux/dvb/frontend.h>
#include <linux/device.h>
#include "bt878.h"
@@ -119,6 +120,8 @@ struct dst_state {
u8 card_info[8];
u8 vendor[8];
u8 board_info[8];
+
+ struct semaphore dst_mutex;
};
struct dst_types {
--
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