Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S941450AbcJGR2e (ORCPT ); Fri, 7 Oct 2016 13:28:34 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:46761 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S938814AbcJGRYq (ORCPT ); Fri, 7 Oct 2016 13:24:46 -0400 From: Mauro Carvalho Chehab To: Linux Media Mailing List Cc: Mauro Carvalho Chehab , Mauro Carvalho Chehab , Andy Lutomirski , Johannes Stezenbach , Jiri Kosina , Patrick Boettcher , Linux Kernel Mailing List , Andy Lutomirski , Michael Krufky , Mauro Carvalho Chehab , =?UTF-8?q?J=C3=B6rg=20Otte?= Subject: [PATCH 02/26] cinergyT2-core: don't do DMA on stack Date: Fri, 7 Oct 2016 14:24:12 -0300 Message-Id: <9589abc05caa366003d399d6f3fe5a5ca2ab8c97.1475860773.git.mchehab@s-opensource.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3505 Lines: 108 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. Signed-off-by: Mauro Carvalho Chehab --- drivers/media/usb/dvb-usb/cinergyT2-core.c | 45 ++++++++++++++++++------------ 1 file changed, 27 insertions(+), 18 deletions(-) diff --git a/drivers/media/usb/dvb-usb/cinergyT2-core.c b/drivers/media/usb/dvb-usb/cinergyT2-core.c index 9fd1527494eb..91640c927776 100644 --- a/drivers/media/usb/dvb-usb/cinergyT2-core.c +++ b/drivers/media/usb/dvb-usb/cinergyT2-core.c @@ -41,6 +41,7 @@ DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr); struct cinergyt2_state { u8 rc_counter; + unsigned char data[64]; }; /* We are missing a release hook with usb_device data */ @@ -50,29 +51,36 @@ 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; + + st->data[0] = CINERGYT2_EP1_CONTROL_STREAM_TRANSFER; + st->data[1] = enable ? 1 : 0; + + return dvb_usb_generic_rw(d, st->data, 2, st->data, 64, 0); } 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; + + st->data[0] = CINERGYT2_EP1_SLEEP_MODE; + st->data[1] = enable ? 0 : 1; + + return dvb_usb_generic_rw(d, st->data, 2, st->data, 3, 0); } 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); + 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"); @@ -141,13 +149,14 @@ 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) { + 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) { @@ -166,13 +175,13 @@ static int cinergyt2_rc_query(struct dvb_usb_device *d, u32 *event, int *state) } /* 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; } -- 2.7.4