From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from galahad.ideasonboard.com ([185.26.127.97]:47339 "EHLO galahad.ideasonboard.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754054AbdLHJvn (ORCPT ); Fri, 8 Dec 2017 04:51:43 -0500 From: Laurent Pinchart To: Niklas =?ISO-8859-1?Q?S=F6derlund?= Cc: Hans Verkuil , linux-media@vger.kernel.org, linux-renesas-soc@vger.kernel.org, tomoharu.fukawa.eb@renesas.com, Kieran Bingham Subject: Re: [PATCH v9 16/28] rcar-vin: add function to manipulate Gen3 chsel value Date: Fri, 08 Dec 2017 11:52:01 +0200 Message-ID: <20173129.GKy7R676Pn@avalon> In-Reply-To: <20171208010842.20047-17-niklas.soderlund+renesas@ragnatech.se> References: <20171208010842.20047-1-niklas.soderlund+renesas@ragnatech.se> <20171208010842.20047-17-niklas.soderlund+renesas@ragnatech.se> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="iso-8859-1" Sender: linux-media-owner@vger.kernel.org List-ID: Hi Niklas, Thank you for the patch. On Friday, 8 December 2017 03:08:30 EET Niklas S=F6derlund wrote: > On Gen3 the CSI-2 routing is controlled by the VnCSI_IFMD register. One > feature of this register is that it's only present in the VIN0 and VIN4 > instances. The register in VIN0 controls the routing for VIN0-3 and the > register in VIN4 controls routing for VIN4-7. >=20 > To be able to control routing from a media device this function is need > to control runtime PM for the subgroup master (VIN0 and VIN4). The > subgroup master must be switched on before the register is manipulated, > once the operation is complete it's safe to switch the master off and > the new routing will still be in effect. >=20 > Signed-off-by: Niklas S=F6derlund > Reviewed-by: Hans Verkuil > --- > drivers/media/platform/rcar-vin/rcar-dma.c | 25 +++++++++++++++++++++++++ > drivers/media/platform/rcar-vin/rcar-vin.h | 2 ++ > 2 files changed, 27 insertions(+) >=20 > diff --git a/drivers/media/platform/rcar-vin/rcar-dma.c > b/drivers/media/platform/rcar-vin/rcar-dma.c index > ace95d5b543a17e3..d2788d8bb9565aaa 100644 > --- a/drivers/media/platform/rcar-vin/rcar-dma.c > +++ b/drivers/media/platform/rcar-vin/rcar-dma.c > @@ -16,6 +16,7 @@ >=20 > #include > #include > +#include >=20 > #include >=20 > @@ -1228,3 +1229,27 @@ int rvin_dma_register(struct rvin_dev *vin, int ir= q) >=20 > return ret; > } > + > +/* ---------------------------------------------------------------------= =2D-- > + * Gen3 CHSEL manipulation > + */ > + > +void rvin_set_chsel(struct rvin_dev *vin, u8 chsel) How about naming the function a bit more explicitly,=20 rvin_set_channel_routing() for instance ? > +{ > + u32 ifmd, vnmc; > + > + pm_runtime_get_sync(vin->dev); Shouldn't you check the return value of this function ? > + > + /* Make register writes take effect immediately */ > + vnmc =3D rvin_read(vin, VNMC_REG) & ~VNMC_VUP; > + rvin_write(vin, vnmc, VNMC_REG); Shouldn't you restore the original value of VNMC at the end of the function= ?=20 What if this races with device access local to the VIN0 or VIN4 instance ? > + ifmd =3D VNCSI_IFMD_DES2 | VNCSI_IFMD_DES1 | VNCSI_IFMD_DES0 | > + VNCSI_IFMD_CSI_CHSEL(chsel); > + > + rvin_write(vin, ifmd, VNCSI_IFMD_REG); > + > + vin_dbg(vin, "Set IFMD 0x%x\n", ifmd); > + > + pm_runtime_put(vin->dev); > +} > diff --git a/drivers/media/platform/rcar-vin/rcar-vin.h > b/drivers/media/platform/rcar-vin/rcar-vin.h index > a440effe4b86af31..7819c760c2c13422 100644 > --- a/drivers/media/platform/rcar-vin/rcar-vin.h > +++ b/drivers/media/platform/rcar-vin/rcar-vin.h > @@ -163,4 +163,6 @@ void rvin_v4l2_unregister(struct rvin_dev *vin); >=20 > const struct rvin_video_format *rvin_format_from_pixel(u32 pixelformat); >=20 > +void rvin_set_chsel(struct rvin_dev *vin, u8 chsel); > + > #endif =2D-=20 Regards, Laurent Pinchart