Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752681AbaJ1NDV (ORCPT ); Tue, 28 Oct 2014 09:03:21 -0400 Received: from 4.mo68.mail-out.ovh.net ([46.105.59.63]:52213 "EHLO mo68.mail-out.ovh.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751062AbaJ1NDT (ORCPT ); Tue, 28 Oct 2014 09:03:19 -0400 X-Greylist: delayed 7798 seconds by postgrey-1.27 at vger.kernel.org; Tue, 28 Oct 2014 09:03:19 EDT From: Julien CHAUVEAU To: Heiko Stuebner , Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , Russell King , linux-arm-kernel@lists.infradead.org (moderated list:ARM/Rockchip SoC...), linux-rockchip@lists.infradead.org (open list:ARM/Rockchip SoC...), devicetree@vger.kernel.org (open list:OPEN FIRMWARE AND...), linux-kernel@vger.kernel.org (open list) Cc: Julien CHAUVEAU Subject: [PATCH v2] ARM: dts: rockchip: use internal pull-up resistors on I2C busses Date: Tue, 28 Oct 2014 11:36:36 +0100 Message-Id: <1414492597-13566-1-git-send-email-julien.chauveau@neo-technologies.fr> X-Mailer: git-send-email 1.9.1 X-Ovh-Tracer-Id: 8211750971526414561 X-Ovh-Remote: 193.248.240.88 (laubervilliers-656-01-116-88.w193-248.abo.wanadoo.fr) X-Ovh-Local: 213.186.33.20 (ns0.ovh.net) X-OVH-SPAMSTATE: OK X-OVH-SPAMSCORE: -100 X-OVH-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeejhedrvdehucetufdoteggodetrfcurfhrohhfihhlvgemucfqggfjnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd X-Spam-Check: DONE|U 0.5/N X-VR-SPAMSTATE: OK X-VR-SPAMSCORE: -100 X-VR-SPAMCAUSE: gggruggvucftvghtrhhoucdtuddrfeejhedrvdehucetufdoteggodetrfcurfhrohhfihhlvgemucfqggfjnecuuegrihhlohhuthemuceftddtnecusecvtfgvtghiphhivghnthhsucdlqddutddtmd Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org According to the I2C bus specification, it is required to use pull-up resistors on the clock and data lines. Probing the I2C busses with i2cdetect results in bad results when no devices are connected and no external resistors are used. This patch configures the I2C busses to use the internal pull-up resistors on the RK3066, RK3188 and RK3288 Rockchip processors. It should also be noted that these default pull settings match the original configuration on these SoCs. Below is the results of using i2cdetect on a I2C bus with no devices connected before (1) and after (2) applying this patch. (1) root@localhost:~# i2cdetect -y 3 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: 03 04 05 06 07 08 09 0a 0b 0c 0d 0e 0f 10: 10 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20: 20 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 30: -- -- -- -- -- rk3x-i2c 2005a000.i2c: timeout, ipd: 0x81, state: 2 -- rk3x-i2c 2005a000.i2c: timeout, ipd: 0x80, state: 2 -- rk3x-i2c 2005a000.i2c: timeout, ipd: 0x80, state: 2 -- rk3x-i2c 2005a000.i2c: timeout, ipd: 0x80, state: 3 -- rk3x-i2c 2005a000.i2c: timeout, ipd: 0x80, state: 3 -- rk3x-i2c 2005a000.i2c: timeout, ipd: 0x80, state: 3 ... (2) root@localhost:~# i2cdetect -y 3 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: -- -- -- -- -- -- -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 30: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 40: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 50: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- Signed-off-by: Julien CHAUVEAU --- Changes since v1: - fix the rk3066a pull settings (only available is pull_none/pull_default) - remove the warnings in the results of i2cdetect arch/arm/boot/dts/rk3066a.dtsi | 20 ++++++++++---------- arch/arm/boot/dts/rk3188.dtsi | 20 ++++++++++---------- arch/arm/boot/dts/rk3288.dtsi | 24 ++++++++++++------------ 3 files changed, 32 insertions(+), 32 deletions(-) diff --git a/arch/arm/boot/dts/rk3066a.dtsi b/arch/arm/boot/dts/rk3066a.dtsi index ad9c2db..dbc1a0b 100644 --- a/arch/arm/boot/dts/rk3066a.dtsi +++ b/arch/arm/boot/dts/rk3066a.dtsi @@ -202,36 +202,36 @@ i2c0 { i2c0_xfer: i2c0-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c1 { i2c1_xfer: i2c1-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c2 { i2c2_xfer: i2c2-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c3 { i2c3_xfer: i2c3-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c4 { i2c4_xfer: i2c4-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; diff --git a/arch/arm/boot/dts/rk3188.dtsi b/arch/arm/boot/dts/rk3188.dtsi index ddaada7..ee2865f 100644 --- a/arch/arm/boot/dts/rk3188.dtsi +++ b/arch/arm/boot/dts/rk3188.dtsi @@ -188,36 +188,36 @@ i2c0 { i2c0_xfer: i2c0-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c1 { i2c1_xfer: i2c1-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c2 { i2c2_xfer: i2c2-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c3 { i2c3_xfer: i2c3-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; i2c4 { i2c4_xfer: i2c4-xfer { - rockchip,pins = , - ; + rockchip,pins = , + ; }; }; diff --git a/arch/arm/boot/dts/rk3288.dtsi b/arch/arm/boot/dts/rk3288.dtsi index 874e66d..9a4b1f7 100644 --- a/arch/arm/boot/dts/rk3288.dtsi +++ b/arch/arm/boot/dts/rk3288.dtsi @@ -636,43 +636,43 @@ i2c0 { i2c0_xfer: i2c0-xfer { - rockchip,pins = <0 15 RK_FUNC_1 &pcfg_pull_none>, - <0 16 RK_FUNC_1 &pcfg_pull_none>; + rockchip,pins = <0 15 RK_FUNC_1 &pcfg_pull_up>, + <0 16 RK_FUNC_1 &pcfg_pull_up>; }; }; i2c1 { i2c1_xfer: i2c1-xfer { - rockchip,pins = <8 4 RK_FUNC_1 &pcfg_pull_none>, - <8 5 RK_FUNC_1 &pcfg_pull_none>; + rockchip,pins = <8 4 RK_FUNC_1 &pcfg_pull_up>, + <8 5 RK_FUNC_1 &pcfg_pull_up>; }; }; i2c2 { i2c2_xfer: i2c2-xfer { - rockchip,pins = <6 9 RK_FUNC_1 &pcfg_pull_none>, - <6 10 RK_FUNC_1 &pcfg_pull_none>; + rockchip,pins = <6 9 RK_FUNC_1 &pcfg_pull_up>, + <6 10 RK_FUNC_1 &pcfg_pull_up>; }; }; i2c3 { i2c3_xfer: i2c3-xfer { - rockchip,pins = <2 16 RK_FUNC_1 &pcfg_pull_none>, - <2 17 RK_FUNC_1 &pcfg_pull_none>; + rockchip,pins = <2 16 RK_FUNC_1 &pcfg_pull_up>, + <2 17 RK_FUNC_1 &pcfg_pull_up>; }; }; i2c4 { i2c4_xfer: i2c4-xfer { - rockchip,pins = <7 17 RK_FUNC_1 &pcfg_pull_none>, - <7 18 RK_FUNC_1 &pcfg_pull_none>; + rockchip,pins = <7 17 RK_FUNC_1 &pcfg_pull_up>, + <7 18 RK_FUNC_1 &pcfg_pull_up>; }; }; i2c5 { i2c5_xfer: i2c5-xfer { - rockchip,pins = <7 19 RK_FUNC_1 &pcfg_pull_none>, - <7 20 RK_FUNC_1 &pcfg_pull_none>; + rockchip,pins = <7 19 RK_FUNC_1 &pcfg_pull_up>, + <7 20 RK_FUNC_1 &pcfg_pull_up>; }; }; -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/