From mboxrd@z Thu Jan 1 00:00:00 1970 From: Uwe =?iso-8859-1?Q?Kleine-K=F6nig?= Subject: Re: [PATCH 6/6] atmel_spi: fix warning In function 'atmel_spi_dma_map_xfer' Date: Sat, 20 Nov 2010 22:48:20 +0100 Message-ID: <20101120214820.GG8942@pengutronix.de> References: <20101120095906.GD4216@game.jcrosoft.org> <1290247733-17834-6-git-send-email-plagnioj@jcrosoft.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: linux-arm-kernel@lists.infradead.org, Patrice Vilchez , Nicolas Ferre , spi-devel-general@lists.sourceforge.net, linux-kernel@vger.kernel.org To: Jean-Christophe PLAGNIOL-VILLARD Return-path: Content-Disposition: inline In-Reply-To: <1290247733-17834-6-git-send-email-plagnioj@jcrosoft.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-spi.vger.kernel.org Hello, [adding spi-devel-general and lkml to Cc:] On Sat, Nov 20, 2010 at 11:08:53AM +0100, Jean-Christophe PLAGNIOL-VILL= ARD wrote: > passing argument 2 of 'dma_map_single' discards qualifiers from point= er target type >=20 > Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD > --- > drivers/spi/atmel_spi.c | 4 +++- > 1 files changed, 3 insertions(+), 1 deletions(-) >=20 > diff --git a/drivers/spi/atmel_spi.c b/drivers/spi/atmel_spi.c > index 154529a..2cf6abd 100644 > --- a/drivers/spi/atmel_spi.c > +++ b/drivers/spi/atmel_spi.c > @@ -352,8 +352,10 @@ atmel_spi_dma_map_xfer(struct atmel_spi *as, str= uct spi_transfer *xfer) > =20 > xfer->tx_dma =3D xfer->rx_dma =3D INVALID_DMA_ADDRESS; > if (xfer->tx_buf) { > + void *nonconst_tx =3D (void *)xfer->tx_buf; /* shut up gcc */ > + > xfer->tx_dma =3D dma_map_single(dev, > - (void *) xfer->tx_buf, xfer->len, > + nonconst_tx, xfer->len, > DMA_TO_DEVICE); Hmm, I wonder if this is the right approach to do this. I'd prefer to have something like: dma_map_single_to_device(struct device *, const void *, ...) don't know if that's sensible though. And I wonder about gcc that your patch makes a difference. Best regards Uwe --=20 Pengutronix e.K. | Uwe Kleine-K=F6nig = | Industrial Linux Solutions | http://www.pengutronix.de/= |