lkml.org 
[lkml]   [2016]   [Oct]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 02/31] cinergyT2-core: don't do DMA on stack
Date
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>
---
drivers/media/usb/dvb-usb/cinergyT2-core.c | 84 ++++++++++++++++++++++--------
1 file changed, 61 insertions(+), 23 deletions(-)

diff --git a/drivers/media/usb/dvb-usb/cinergyT2-core.c b/drivers/media/usb/dvb-usb/cinergyT2-core.c
index 9fd1527494eb..d85c0c4d4042 100644
--- a/drivers/media/usb/dvb-usb/cinergyT2-core.c
+++ b/drivers/media/usb/dvb-usb/cinergyT2-core.c
@@ -41,6 +41,8 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);

struct cinergyt2_state {
u8 rc_counter;
+ unsigned char data[64];
+ struct mutex data_mutex;
};

/* We are missing a release hook with usb_device data */
@@ -50,33 +52,52 @@ static struct dvb_usb_device_properties cinergyt2_properties;

static int cinergyt2_streaming_ctrl(struct dvb_usb_adapter *adap, int enable)
{
- char buf[] = { CINERGYT2_EP1_CONTROL_STREAM_TRANSFER, enable ? 1 : 0 };
- char result[64];
- return dvb_usb_generic_rw(adap->dev, buf, sizeof(buf), result,
- sizeof(result), 0);
+ struct dvb_usb_device *d = adap->dev;
+ struct cinergyt2_state *st = d->priv;
+ int ret;
+
+ mutex_lock(&st->data_mutex);
+ st->data[0] = CINERGYT2_EP1_CONTROL_STREAM_TRANSFER;
+ st->data[1] = enable ? 1 : 0;
+
+ ret = dvb_usb_generic_rw(d, st->data, 2, st->data, 64, 0);
+ mutex_unlock(&st->data_mutex);
+
+ return ret;
}

static int cinergyt2_power_ctrl(struct dvb_usb_device *d, int enable)
{
- char buf[] = { CINERGYT2_EP1_SLEEP_MODE, enable ? 0 : 1 };
- char state[3];
- return dvb_usb_generic_rw(d, buf, sizeof(buf), state, sizeof(state), 0);
+ struct cinergyt2_state *st = d->priv;
+ int ret;
+
+ mutex_lock(&st->data_mutex);
+ st->data[0] = CINERGYT2_EP1_SLEEP_MODE;
+ st->data[1] = enable ? 0 : 1;
+
+ ret = dvb_usb_generic_rw(d, st->data, 2, st->data, 3, 0);
+ mutex_unlock(&st->data_mutex);
+
+ return ret;
}

static int cinergyt2_frontend_attach(struct dvb_usb_adapter *adap)
{
- char query[] = { CINERGYT2_EP1_GET_FIRMWARE_VERSION };
- char state[3];
+ struct dvb_usb_device *d = adap->dev;
+ struct cinergyt2_state *st = d->priv;
int ret;

adap->fe_adap[0].fe = cinergyt2_fe_attach(adap->dev);

- ret = dvb_usb_generic_rw(adap->dev, query, sizeof(query), state,
- sizeof(state), 0);
+ mutex_lock(&st->data_mutex);
+ st->data[0] = CINERGYT2_EP1_GET_FIRMWARE_VERSION;
+
+ ret = dvb_usb_generic_rw(d, st->data, 1, st->data, 3, 0);
if (ret < 0) {
deb_rc("cinergyt2_power_ctrl() Failed to retrieve sleep "
"state info\n");
}
+ mutex_unlock(&st->data_mutex);

/* Copy this pointer as we are gonna need it in the release phase */
cinergyt2_usb_device = adap->dev;
@@ -141,13 +162,16 @@ static int repeatable_keys[] = {
static int cinergyt2_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
{
struct cinergyt2_state *st = d->priv;
- u8 key[5] = {0, 0, 0, 0, 0}, cmd = CINERGYT2_EP1_GET_RC_EVENTS;
int i;

*state = REMOTE_NO_KEY_PRESSED;

- dvb_usb_generic_rw(d, &cmd, 1, key, sizeof(key), 0);
- if (key[4] == 0xff) {
+ mutex_lock(&st->data_mutex);
+ st->data[0] = CINERGYT2_EP1_GET_RC_EVENTS;
+
+ dvb_usb_generic_rw(d, st->data, 1, st->data, 5, 0);
+
+ if (st->data[4] == 0xff) {
/* key repeat */
st->rc_counter++;
if (st->rc_counter > RC_REPEAT_DELAY) {
@@ -157,31 +181,45 @@ static int cinergyt2_rc_query(struct dvb_usb_device *d, u32 *event, int *state)
*event = d->last_event;
deb_rc("repeat key, event %x\n",
*event);
- return 0;
+ goto ret;
}
}
deb_rc("repeated key (non repeatable)\n");
}
- return 0;
+ goto ret;
}

/* hack to pass checksum on the custom field */
- key[2] = ~key[1];
- dvb_usb_nec_rc_key_to_event(d, key, event, state);
- if (key[0] != 0) {
+ st->data[2] = ~st->data[1];
+ dvb_usb_nec_rc_key_to_event(d, st->data, event, state);
+ if (st->data[0] != 0) {
if (*event != d->last_event)
st->rc_counter = 0;

- deb_rc("key: %*ph\n", 5, key);
+ deb_rc("key: %*ph\n", 5, st->data);
}
- return 0;
+
+ret:
+ mutex_unlock(&st->data_mutex);
+ return ret;
}

static int cinergyt2_usb_probe(struct usb_interface *intf,
const struct usb_device_id *id)
{
- return dvb_usb_device_init(intf, &cinergyt2_properties,
- THIS_MODULE, NULL, adapter_nr);
+ struct dvb_usb_device *d;
+ struct cinergyt2_state *st;
+ int ret;
+
+ ret = dvb_usb_device_init(intf, &cinergyt2_properties,
+ THIS_MODULE, &d, adapter_nr);
+ if (ret < 0)
+ return ret;
+
+ st = d->priv;
+ mutex_init(&st->data_mutex);
+
+ return 0;
}


--
2.7.4

\
 
 \ /
  Last update: 2016-10-11 12:14    [W:0.241 / U:2.344 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site