[PATCH 1/1] media: dvbsky: use a single mutex and state buffers for all R/W ops

From: Andrei Koshkosh
Date: Fri Nov 08 2019 - 14:14:53 EST


Signed-off-by: Andrei Koshkosh <andreykosh000@xxxxxxx>
---
drivers/media/usb/dvb-usb-v2/dvbsky.c | 25 +++++++++----------------
1 file changed, 9 insertions(+), 16 deletions(-)

diff --git a/drivers/media/usb/dvb-usb-v2/dvbsky.c b/drivers/media/usb/dvb-usb-v2/dvbsky.c
index c41e10b..7d36f5f 100644
--- a/drivers/media/usb/dvb-usb-v2/dvbsky.c
+++ b/drivers/media/usb/dvb-usb-v2/dvbsky.c
@@ -22,7 +22,6 @@ MODULE_PARM_DESC(disable_rc, "Disable inbuilt IR receiver.");
DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr);

struct dvbsky_state {
- struct mutex stream_mutex;
u8 ibuf[DVBSKY_BUF_LEN];
u8 obuf[DVBSKY_BUF_LEN];
u8 last_lock;
@@ -61,16 +60,18 @@ static int dvbsky_stream_ctrl(struct dvb_usb_device *d, u8 onoff)
{
struct dvbsky_state *state = d_to_priv(d);
int ret;
- u8 obuf_pre[3] = { 0x37, 0, 0 };
- u8 obuf_post[3] = { 0x36, 3, 0 };
+ static u8 obuf_pre[3] = { 0x37, 0, 0 };
+ static u8 obuf_post[3] = { 0x36, 3, 0 };

- mutex_lock(&state->stream_mutex);
- ret = dvbsky_usb_generic_rw(d, obuf_pre, 3, NULL, 0);
+ mutex_lock(&d->usb_mutex);
+ memcpy(state->obuf, obuf_pre, 3);
+ ret = dvb_usbv2_generic_write_locked(d, state->obuf, 3);
if (!ret && onoff) {
msleep(20);
- ret = dvbsky_usb_generic_rw(d, obuf_post, 3, NULL, 0);
+ memcpy(state->obuf, obuf_post, 3);
+ ret = dvb_usbv2_generic_write_locked(d, state->obuf, 3);
}
- mutex_unlock(&state->stream_mutex);
+ mutex_unlock(&d->usb_mutex);
return ret;
}

@@ -592,15 +593,7 @@ static int dvbsky_identify_state(struct dvb_usb_device *d, const char **name)
static int dvbsky_init(struct dvb_usb_device *d)
{
struct dvbsky_state *state = d_to_priv(d);
-
- /* use default interface */
- /*
- ret = usb_set_interface(d->udev, 0, 0);
- if (ret)
- return ret;
- */
- mutex_init(&state->stream_mutex);
-
+
state->last_lock = 0;

return 0;
--
2.7.4