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authorMauro Carvalho Chehab <mchehab@s-opensource.com>2016-10-07 12:16:59 +0300
committerMauro Carvalho Chehab <mchehab@s-opensource.com>2016-10-14 18:36:52 +0300
commit0d43c0ff8b7e0a76136c602625efa5e6919baf9c (patch)
tree58162a740167c7613bb8945f6c7865d9e23ea348 /drivers/media
parentc2730eef5fa180eec853f3775bebc4d74e6e6697 (diff)
downloadlinux-0d43c0ff8b7e0a76136c602625efa5e6919baf9c.tar.xz
[media] cinergyT2-fe: don't do DMA on stack
The USB control messages require DMA to work. We cannot pass a stack-allocated buffer, as it is not warranted that the stack would be into a DMA enabled area. Reviewed-by: Patrick Boettcher <patrick.boettcher@posteo.de> Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
Diffstat (limited to 'drivers/media')
-rw-r--r--drivers/media/usb/dvb-usb/cinergyT2-fe.c56
1 files changed, 33 insertions, 23 deletions
diff --git a/drivers/media/usb/dvb-usb/cinergyT2-fe.c b/drivers/media/usb/dvb-usb/cinergyT2-fe.c
index fd8edcb56e61..2d29b4174dba 100644
--- a/drivers/media/usb/dvb-usb/cinergyT2-fe.c
+++ b/drivers/media/usb/dvb-usb/cinergyT2-fe.c
@@ -139,6 +139,10 @@ static uint16_t compute_tps(struct dtv_frontend_properties *op)
struct cinergyt2_fe_state {
struct dvb_frontend fe;
struct dvb_usb_device *d;
+
+ unsigned char data[64];
+ struct mutex data_mutex;
+
struct dvbt_get_status_msg status;
};
@@ -146,28 +150,31 @@ static int cinergyt2_fe_read_status(struct dvb_frontend *fe,
enum fe_status *status)
{
struct cinergyt2_fe_state *state = fe->demodulator_priv;
- struct dvbt_get_status_msg result;
- u8 cmd[] = { CINERGYT2_EP1_GET_TUNER_STATUS };
int ret;
- ret = dvb_usb_generic_rw(state->d, cmd, sizeof(cmd), (u8 *)&result,
- sizeof(result), 0);
+ mutex_lock(&state->data_mutex);
+ state->data[0] = CINERGYT2_EP1_GET_TUNER_STATUS;
+
+ ret = dvb_usb_generic_rw(state->d, state->data, 1,
+ state->data, sizeof(state->status), 0);
+ if (!ret)
+ memcpy(&state->status, state->data, sizeof(state->status));
+ mutex_unlock(&state->data_mutex);
+
if (ret < 0)
return ret;
- state->status = result;
-
*status = 0;
- if (0xffff - le16_to_cpu(result.gain) > 30)
+ if (0xffff - le16_to_cpu(state->status.gain) > 30)
*status |= FE_HAS_SIGNAL;
- if (result.lock_bits & (1 << 6))
+ if (state->status.lock_bits & (1 << 6))
*status |= FE_HAS_LOCK;
- if (result.lock_bits & (1 << 5))
+ if (state->status.lock_bits & (1 << 5))
*status |= FE_HAS_SYNC;
- if (result.lock_bits & (1 << 4))
+ if (state->status.lock_bits & (1 << 4))
*status |= FE_HAS_CARRIER;
- if (result.lock_bits & (1 << 1))
+ if (state->status.lock_bits & (1 << 1))
*status |= FE_HAS_VITERBI;
if ((*status & (FE_HAS_CARRIER | FE_HAS_VITERBI | FE_HAS_SYNC)) !=
@@ -232,34 +239,36 @@ static int cinergyt2_fe_set_frontend(struct dvb_frontend *fe)
{
struct dtv_frontend_properties *fep = &fe->dtv_property_cache;
struct cinergyt2_fe_state *state = fe->demodulator_priv;
- struct dvbt_set_parameters_msg param;
- char result[2];
+ struct dvbt_set_parameters_msg *param;
int err;
- param.cmd = CINERGYT2_EP1_SET_TUNER_PARAMETERS;
- param.tps = cpu_to_le16(compute_tps(fep));
- param.freq = cpu_to_le32(fep->frequency / 1000);
- param.flags = 0;
+ mutex_lock(&state->data_mutex);
+
+ param = (void *)state->data;
+ param->cmd = CINERGYT2_EP1_SET_TUNER_PARAMETERS;
+ param->tps = cpu_to_le16(compute_tps(fep));
+ param->freq = cpu_to_le32(fep->frequency / 1000);
+ param->flags = 0;
switch (fep->bandwidth_hz) {
default:
case 8000000:
- param.bandwidth = 8;
+ param->bandwidth = 8;
break;
case 7000000:
- param.bandwidth = 7;
+ param->bandwidth = 7;
break;
case 6000000:
- param.bandwidth = 6;
+ param->bandwidth = 6;
break;
}
- err = dvb_usb_generic_rw(state->d,
- (char *)&param, sizeof(param),
- result, sizeof(result), 0);
+ err = dvb_usb_generic_rw(state->d, state->data, sizeof(*param),
+ state->data, 2, 0);
if (err < 0)
err("cinergyt2_fe_set_frontend() Failed! err=%d\n", err);
+ mutex_unlock(&state->data_mutex);
return (err < 0) ? err : 0;
}
@@ -281,6 +290,7 @@ struct dvb_frontend *cinergyt2_fe_attach(struct dvb_usb_device *d)
s->d = d;
memcpy(&s->fe.ops, &cinergyt2_fe_ops, sizeof(struct dvb_frontend_ops));
s->fe.demodulator_priv = s;
+ mutex_init(&s->data_mutex);
return &s->fe;
}