Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753390AbcJKKMj (ORCPT ); Tue, 11 Oct 2016 06:12:39 -0400 Received: from bombadil.infradead.org ([198.137.202.9]:56882 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752998AbcJKKLj (ORCPT ); Tue, 11 Oct 2016 06:11:39 -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 v2 18/31] gp8psk: don't do DMA on stack Date: Tue, 11 Oct 2016 07:09:33 -0300 Message-Id: <632081ba085ddf0ded63cce3dbcf3870485d3cd3.1476179975.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: 2512 Lines: 79 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/gp8psk.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/drivers/media/usb/dvb-usb/gp8psk.c b/drivers/media/usb/dvb-usb/gp8psk.c index 5d0384dd45b5..fa215ad37f7b 100644 --- a/drivers/media/usb/dvb-usb/gp8psk.c +++ b/drivers/media/usb/dvb-usb/gp8psk.c @@ -24,6 +24,10 @@ MODULE_PARM_DESC(debug, "set debugging level (1=info,xfer=2,rc=4 (or-able))." DV DVB_DEFINE_MOD_OPT_ADAPTER_NR(adapter_nr); +struct gp8psk_state { + unsigned char data[80]; +}; + static int gp8psk_get_fw_version(struct dvb_usb_device *d, u8 *fw_vers) { return (gp8psk_usb_in_op(d, GET_FW_VERS, 0, 0, fw_vers, 6)); @@ -53,17 +57,19 @@ static void gp8psk_info(struct dvb_usb_device *d) int gp8psk_usb_in_op(struct dvb_usb_device *d, u8 req, u16 value, u16 index, u8 *b, int blen) { + struct gp8psk_state *st = d->priv; int ret = 0,try = 0; if ((ret = mutex_lock_interruptible(&d->usb_mutex))) return ret; while (ret >= 0 && ret != blen && try < 3) { + memcpy(st->data, b, blen); ret = usb_control_msg(d->udev, usb_rcvctrlpipe(d->udev,0), req, USB_TYPE_VENDOR | USB_DIR_IN, - value,index,b,blen, + value, index, st->data, blen, 2000); deb_info("reading number %d (ret: %d)\n",try,ret); try++; @@ -86,6 +92,7 @@ int gp8psk_usb_in_op(struct dvb_usb_device *d, u8 req, u16 value, u16 index, u8 int gp8psk_usb_out_op(struct dvb_usb_device *d, u8 req, u16 value, u16 index, u8 *b, int blen) { + struct gp8psk_state *st = d->priv; int ret; deb_xfer("out: req. %x, val: %x, ind: %x, buffer: ",req,value,index); @@ -94,11 +101,12 @@ int gp8psk_usb_out_op(struct dvb_usb_device *d, u8 req, u16 value, if ((ret = mutex_lock_interruptible(&d->usb_mutex))) return ret; + memcpy(st->data, b, blen); if (usb_control_msg(d->udev, usb_sndctrlpipe(d->udev,0), req, USB_TYPE_VENDOR | USB_DIR_OUT, - value,index,b,blen, + value,index, st->data, blen, 2000) != blen) { warn("usb out operation failed."); ret = -EIO; @@ -265,6 +273,8 @@ static struct dvb_usb_device_properties gp8psk_properties = { .usb_ctrl = CYPRESS_FX2, .firmware = "dvb-usb-gp8psk-01.fw", + .size_of_priv = sizeof(struct gp8psk_state), + .num_adapters = 1, .adapter = { { -- 2.7.4