From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrzej Hajda Subject: Re: [PATCH 05/11] drm/bridge: analogix-anx78xx: correct value of TX_P0 Date: Mon, 16 Sep 2019 12:02:09 +0200 Message-ID: References: <20190815004854.19860-1-masneyb@onstation.org> <20190815004854.19860-6-masneyb@onstation.org> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190815004854.19860-6-masneyb@onstation.org> Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Brian Masney , bjorn.andersson@linaro.org, robh+dt@kernel.org, agross@kernel.org, narmstrong@baylibre.com, robdclark@gmail.com, sean@poorly.run Cc: airlied@linux.ie, daniel@ffwll.ch, mark.rutland@arm.com, Laurent.pinchart@ideasonboard.com, jonas@kwiboo.se, jernej.skrabec@siol.net, linus.walleij@linaro.org, enric.balletbo@collabora.com, dri-devel@lists.freedesktop.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, freedreno@lists.freedesktop.org List-Id: devicetree@vger.kernel.org On 15.08.2019 02:48, Brian Masney wrote: > When attempting to configure this driver on a Nexus 5 phone (msm8974), > setting up the dummy i2c bus for TX_P0 would fail due to an -EBUSY > error. The downstream MSM kernel sources [1] shows that the proper value > for TX_P0 is 0x78, not 0x70, so correct the value to allow device > probing to succeed. > > [1] https://github.com/AICP/kernel_lge_hammerhead/blob/n7.1/drivers/video/slimport/slimport_tx_reg.h > > Signed-off-by: Brian Masney > --- > drivers/gpu/drm/bridge/analogix-anx78xx.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/bridge/analogix-anx78xx.h b/drivers/gpu/drm/bridge/analogix-anx78xx.h > index 25e063bcecbc..bc511fc605c9 100644 > --- a/drivers/gpu/drm/bridge/analogix-anx78xx.h > +++ b/drivers/gpu/drm/bridge/analogix-anx78xx.h > @@ -6,7 +6,7 @@ > #ifndef __ANX78xx_H > #define __ANX78xx_H > > -#define TX_P0 0x70 > +#define TX_P0 0x78 This bothers me little. There are no upstream users, grepping android sources suggests that both values can be used [1][2]  (grep for "#define TX_P0"), moreover there is code suggesting both values can be valid [3]. Could you verify datasheet which i2c slave addresses are valid for this chip, if both I guess this patch should be reworked. [1]: https://android.googlesource.com/kernel/msm/+/android-msm-flo-3.4-jb-mr2/drivers/misc/slimport_anx7808/slimport_tx_reg.h [2]: https://github.com/AndroidGX/SimpleGX-MM-6.0_H815_20d/blob/master/drivers/video/slimport/anx7812/slimport7812_tx_reg.h [3]: https://github.com/commaai/android_kernel_leeco_msm8996/blob/master/drivers/video/msm/mdss/dp/slimport_custom_declare.h#L73 Regards Andrzej > #define TX_P1 0x7a > #define TX_P2 0x72 >