From d28d57629ffcd30e11a6085e15ee1327fea60b60 Mon Sep 17 00:00:00 2001 From: Manu Abraham Date: Tue, 8 Nov 2005 21:35:36 -0800 Subject: [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 Signed-off-by: Manu Abraham Signed-off-by: Michael Krufky Cc: Johannes Stezenbach Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/media/dvb/bt8xx/dst.c | 34 +++++++++++++++++++++------------- 1 file changed, 21 insertions(+), 13 deletions(-) (limited to 'drivers/media/dvb/bt8xx/dst.c') diff --git a/drivers/media/dvb/bt8xx/dst.c b/drivers/media/dvb/bt8xx/dst.c index bc833a55438..0c718dca09c 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); -- cgit v1.2.3