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From:   Andrei Koshkosh <andreykosh000@mail.ru>
To:     Mauro Carvalho Chehab <mchehab@kernel.org>
Cc:     Andrei Koshkosh <andreykosh000@mail.ru>,
        linux-media@vger.kernel.org, Sean Young <sean@mess.org>,
        Jan Pieter van Woerkom <jp@jpvw.nl>,
        =?UTF-8?q?Stefan=20Br=C3=BCns?= <stefan.bruens@rwth-aachen.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-kernel@vger.kernel.org
Subject: [PATCH 1/1] media: dvbsky: use a single mutex and state buffers for all R/W ops
Date:   Fri,  8 Nov 2019 21:15:13 +0300
Message-Id: <1573236913-16642-1-git-send-email-andreykosh000@mail.ru>
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Signed-off-by: Andrei Koshkosh <andreykosh000@mail.ru>
---
 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