[PATCH v2 0/4] ARM: dts: meson: set pinmux bias

[PATCH v2 0/4] ARM: dts: meson: set pinmux bias

[Jerome Brunet]

On Amlogic chipsets, the bias set through pinconf applies to the pad
itself, not only the GPIO function. This means that even when we change
the function of the pad from GPIO to anything else, the bias previously
set still applies.

While trying to boot from SPI, I noticed the eMMC was not working anymore.
Even if the related eMMC pad are not used by the SPI, the ROM code sets a
pull-down on the eMMC pad and leaves it that way. This breaks the eMMC
later on, in both u-boot and Linux.

The underlying issue is that we inherit whatever was left by previous user
of the pad (pinconf, u-boot or the ROM code). As a consequence, the actual
setup we get is undefined.

There is nothing mentioned in the documentation about pad bias and pinmux
function, however leaving it undefined is not an option.

This patchset consistently disable the pad bias for every pinmux functions.
It seems to work well, we can only assume that the necessary bias (if any)
is already provided by the pin function itself.

I can't really test every pinmux configuration and it is fairly possible
I missed something so it would be nice if more people could confirm if
nothing (new) is broken after applying this series.

One things could be the i2c. Usually the i2c pull-ups are physically
present on the board but, if they are missing on platform, we may define
a special pinmux setting with pull-up enabled.

One last gotcha, I recently posted fixups around bias setting to pinctrl
which have been merged: [0] [1]. These must be applied before applying this
series, otherwise when requesting 'bias-disable' you'll probably get a
pull-down instead.

Changes since v1 [2]:
 * Fix wrongly placed bias-disable on meson8

[0]: https://lkml.kernel.org/r/20181023160319.27003-1-jbrunet@baylibre.com
[1]: https://lkml.kernel.org/r/20181029151340.9087-1-jbrunet@baylibre.com
[2]: https://lkml.kernel.org/r/20181108104426.1877-1-jbrunet@baylibre.com

Jerome Brunet (4):
  arm64: dts: meson: remove extra subnode in mmc clk_gate pinmux
  arm64: dts: meson: disable pad bias for mmc pinmuxes
  arm64: dts: meson: consistently disable pin bias
  ARM: dts: meson: consistently disable pin bias

 arch/arm/boot/dts/meson8.dtsi               |  12 +++
 arch/arm/boot/dts/meson8b.dtsi              |   9 ++
 arch/arm/boot/dts/meson8m2.dtsi             |   1 +
 arch/arm64/boot/dts/amlogic/meson-axg.dtsi  | 111 ++++++++++++++++++--
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi |  60 +++++++++--
 arch/arm64/boot/dts/amlogic/meson-gxl.dtsi  |  62 +++++++++--
 6 files changed, 231 insertions(+), 24 deletions(-)

-- 
2.19.1

[PATCH v2 1/4] arm64: dts: meson: remove extra subnode in mmc clk_gate pinmux

[Jerome Brunet]

In the pinmux of the mmc clk_gate nodes, we define 2 subnodes. One for
the function definition, the other for the bias. This is not necessary
since we can define the function and the bias in the same subnode.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-axg.dtsi  | 6 ------
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 9 ---------
 arch/arm64/boot/dts/amlogic/meson-gxl.dtsi  | 9 ---------
 3 files changed, 24 deletions(-)

diff --git a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
index eb46db001ce0..e86f5f721f8f 100644
--- a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
@@ -280,9 +280,6 @@
 					mux {
 						groups = "BOOT_8";
 						function = "gpio_periphs";
-					};
-					cfg-pull-down {
-						pins = "BOOT_8";
 						bias-pull-down;
 					};
 				};
@@ -513,9 +510,6 @@
 					mux {
 						groups = "GPIOX_4";
 						function = "gpio_periphs";
-					};
-					cfg-pull-down {
-						pins = "GPIOX_4";
 						bias-pull-down;
 					};
 				};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
index 524f533e41d4..1cb8e7e0d0da 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
@@ -377,9 +377,6 @@
 			mux {
 				groups = "BOOT_8";
 				function = "gpio_periphs";
-			};
-			cfg-pull-down {
-				pins = "BOOT_8";
 				bias-pull-down;
 			};
 		};
@@ -426,9 +423,6 @@
 			mux {
 				groups = "CARD_2";
 				function = "gpio_periphs";
-			};
-			cfg-pull-down {
-				pins = "CARD_2";
 				bias-pull-down;
 			};
 		};
@@ -449,9 +443,6 @@
 			mux {
 				groups = "GPIOX_4";
 				function = "gpio_periphs";
-			};
-			cfg-pull-down {
-				pins = "GPIOX_4";
 				bias-pull-down;
 			};
 		};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
index 8ccab9a1ebcc..7cfee40d89e9 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
@@ -324,9 +324,6 @@
 			mux {
 				groups = "BOOT_8";
 				function = "gpio_periphs";
-			};
-			cfg-pull-down {
-				pins = "BOOT_8";
 				bias-pull-down;
 			};
 		};
@@ -373,9 +370,6 @@
 			mux {
 				groups = "CARD_2";
 				function = "gpio_periphs";
-			};
-			cfg-pull-down {
-				pins = "CARD_2";
 				bias-pull-down;
 			};
 		};
@@ -396,9 +390,6 @@
 			mux {
 				groups = "GPIOX_4";
 				function = "gpio_periphs";
-			};
-			cfg-pull-down {
-				pins = "GPIOX_4";
 				bias-pull-down;
 			};
 		};
-- 
2.19.1

[PATCH v2 2/4] arm64: dts: meson: disable pad bias for mmc pinmuxes

[Jerome Brunet]

In some cases (such as a boot from SPI) the bootloader or the ROM code may
leave a bias pull-down on the mmc pins. If so the MMC will fail during the
initialisation.

Explicitly disabling the pinmux solves the problem.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-axg.dtsi  | 2 ++
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi | 4 ++++
 arch/arm64/boot/dts/amlogic/meson-gxl.dtsi  | 4 ++++
 3 files changed, 10 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
index e86f5f721f8f..bc427b9d3e13 100644
--- a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
@@ -273,6 +273,7 @@
 							 "emmc_cmd",
 							 "emmc_ds";
 						function = "emmc";
+						bias-disable;
 					};
 				};
 
@@ -503,6 +504,7 @@
 							 "sdio_cmd",
 							 "sdio_clk";
 						function = "sdio";
+						bias-disable;
 					};
 				};
 
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
index 1cb8e7e0d0da..32ef82321340 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
@@ -363,6 +363,7 @@
 				       "emmc_cmd",
 				       "emmc_clk";
 				function = "emmc";
+				bias-disable;
 			};
 		};
 
@@ -370,6 +371,7 @@
 			mux {
 				groups = "emmc_ds";
 				function = "emmc";
+				bias-disable;
 			};
 		};
 
@@ -416,6 +418,7 @@
 				       "sdcard_cmd",
 				       "sdcard_clk";
 				function = "sdcard";
+				bias-disable;
 			};
 		};
 
@@ -436,6 +439,7 @@
 				       "sdio_cmd",
 				       "sdio_clk";
 				function = "sdio";
+				bias-disable;
 			};
 		};
 
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
index 7cfee40d89e9..cfeec5579726 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
@@ -310,6 +310,7 @@
 				       "emmc_cmd",
 				       "emmc_clk";
 				function = "emmc";
+				bias-disable;
 			};
 		};
 
@@ -317,6 +318,7 @@
 			mux {
 				groups = "emmc_ds";
 				function = "emmc";
+				bias-disable;
 			};
 		};
 
@@ -363,6 +365,7 @@
 				       "sdcard_cmd",
 				       "sdcard_clk";
 				function = "sdcard";
+				bias-disable;
 			};
 		};
 
@@ -383,6 +386,7 @@
 				       "sdio_cmd",
 				       "sdio_clk";
 				function = "sdio";
+				bias-disable;
 			};
 		};
 
-- 
2.19.1

[PATCH v2 3/4] arm64: dts: meson: consistently disable pin bias

[Jerome Brunet]

On Amlogic chipsets, the bias set through pinconf applies to the pad
itself, not only the GPIO function. This means that even when we change
the function of the pad from GPIO to anything else, the bias previously
set still applies.

As we have seen with the eMMC, depending on the bias type and the function,
it may trigger problems.

The underlying issue is that we inherit whatever was left by previous user
of the pad (pinconf, u-boot or the ROM code). As a consequence, the actual
setup we will get is undefined.

There is nothing mentioned in the documentation about pad bias and pinmux
function, however leaving it undefined is not an option.

This change consistently disable the pad bias for every pinmux functions.
It seems to work well, we can only assume that the necessary bias (if any)
is already provided by the pin function itself.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm64/boot/dts/amlogic/meson-axg.dtsi  | 103 ++++++++++++++++++++
 arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi |  47 +++++++++
 arch/arm64/boot/dts/amlogic/meson-gxl.dtsi  |  49 ++++++++++
 3 files changed, 199 insertions(+)

diff --git a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
index bc427b9d3e13..e0139f174726 100644
--- a/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-axg.dtsi
@@ -200,6 +200,7 @@
 						groups = "i2c0_sck",
 							 "i2c0_sda";
 						function = "i2c0";
+						bias-disable;
 					};
 				};
 
@@ -208,6 +209,7 @@
 						groups = "i2c1_sck_x",
 							 "i2c1_sda_x";
 						function = "i2c1";
+						bias-disable;
 					};
 				};
 
@@ -216,6 +218,7 @@
 						groups = "i2c1_sck_z",
 							 "i2c1_sda_z";
 						function = "i2c1";
+						bias-disable;
 					};
 				};
 
@@ -224,6 +227,7 @@
 						groups = "i2c2_sck_a",
 							 "i2c2_sda_a";
 						function = "i2c2";
+						bias-disable;
 					};
 				};
 
@@ -232,6 +236,7 @@
 						groups = "i2c2_sck_x",
 							 "i2c2_sda_x";
 						function = "i2c2";
+						bias-disable;
 					};
 				};
 
@@ -240,6 +245,7 @@
 						groups = "i2c3_sda_a6",
 							 "i2c3_sck_a7";
 						function = "i2c3";
+						bias-disable;
 					};
 				};
 
@@ -248,6 +254,7 @@
 						groups = "i2c3_sda_a12",
 							 "i2c3_sck_a13";
 						function = "i2c3";
+						bias-disable;
 					};
 				};
 
@@ -256,6 +263,7 @@
 						groups = "i2c3_sda_a19",
 							 "i2c3_sck_a20";
 						function = "i2c3";
+						bias-disable;
 					};
 				};
 
@@ -302,6 +310,7 @@
 							 "eth_txd2_rgmii",
 							 "eth_txd3_rgmii";
 						function = "eth";
+						bias-disable;
 					};
 				};
 
@@ -322,6 +331,7 @@
 							 "eth_txd2_rgmii",
 							 "eth_txd3_rgmii";
 						function = "eth";
+						bias-disable;
 					};
 				};
 
@@ -337,6 +347,7 @@
 							 "eth_txd0_x",
 							 "eth_txd1_x";
 						function = "eth";
+						bias-disable;
 					};
 				};
 
@@ -352,6 +363,7 @@
 							 "eth_txd0_y",
 							 "eth_txd1_y";
 						function = "eth";
+						bias-disable;
 					};
 				};
 
@@ -359,6 +371,7 @@
 					mux {
 						groups = "mclk_b";
 						function = "mclk_b";
+						bias-disable;
 					};
 				};
 
@@ -366,6 +379,7 @@
 					mux {
 						groups = "mclk_c";
 						function = "mclk_c";
+						bias-disable;
 					};
 				};
 
@@ -373,6 +387,7 @@
 					mux {
 						groups = "pdm_dclk_a14";
 						function = "pdm";
+						bias-disable;
 					};
 				};
 
@@ -380,6 +395,7 @@
 					mux {
 						groups = "pdm_dclk_a19";
 						function = "pdm";
+						bias-disable;
 					};
 				};
 
@@ -387,6 +403,7 @@
 					mux {
 						groups = "pdm_din0";
 						function = "pdm";
+						bias-disable;
 					};
 				};
 
@@ -394,6 +411,7 @@
 					mux {
 						groups = "pdm_din1";
 						function = "pdm";
+						bias-disable;
 					};
 				};
 
@@ -401,6 +419,7 @@
 					mux {
 						groups = "pdm_din2";
 						function = "pdm";
+						bias-disable;
 					};
 				};
 
@@ -408,6 +427,7 @@
 					mux {
 						groups = "pdm_din3";
 						function = "pdm";
+						bias-disable;
 					};
 				};
 
@@ -415,6 +435,7 @@
 					mux {
 						groups = "pwm_a_a";
 						function = "pwm_a";
+						bias-disable;
 					};
 				};
 
@@ -422,6 +443,7 @@
 					mux {
 						groups = "pwm_a_x18";
 						function = "pwm_a";
+						bias-disable;
 					};
 				};
 
@@ -429,6 +451,7 @@
 					mux {
 						groups = "pwm_a_x20";
 						function = "pwm_a";
+						bias-disable;
 					};
 				};
 
@@ -436,6 +459,7 @@
 					mux {
 						groups = "pwm_a_z";
 						function = "pwm_a";
+						bias-disable;
 					};
 				};
 
@@ -443,6 +467,7 @@
 					mux {
 						groups = "pwm_b_a";
 						function = "pwm_b";
+						bias-disable;
 					};
 				};
 
@@ -450,6 +475,7 @@
 					mux {
 						groups = "pwm_b_x";
 						function = "pwm_b";
+						bias-disable;
 					};
 				};
 
@@ -457,6 +483,7 @@
 					mux {
 						groups = "pwm_b_z";
 						function = "pwm_b";
+						bias-disable;
 					};
 				};
 
@@ -464,6 +491,7 @@
 					mux {
 						groups = "pwm_c_a";
 						function = "pwm_c";
+						bias-disable;
 					};
 				};
 
@@ -471,6 +499,7 @@
 					mux {
 						groups = "pwm_c_x10";
 						function = "pwm_c";
+						bias-disable;
 					};
 				};
 
@@ -478,6 +507,7 @@
 					mux {
 						groups = "pwm_c_x17";
 						function = "pwm_c";
+						bias-disable;
 					};
 				};
 
@@ -485,6 +515,7 @@
 					mux {
 						groups = "pwm_d_x11";
 						function = "pwm_d";
+						bias-disable;
 					};
 				};
 
@@ -492,6 +523,7 @@
 					mux {
 						groups = "pwm_d_x16";
 						function = "pwm_d";
+						bias-disable;
 					};
 				};
 
@@ -520,6 +552,7 @@
 					mux {
 						groups = "spdif_in_z";
 						function = "spdif_in";
+						bias-disable;
 					};
 				};
 
@@ -527,6 +560,7 @@
 					mux {
 						groups = "spdif_in_a1";
 						function = "spdif_in";
+						bias-disable;
 					};
 				};
 
@@ -534,6 +568,7 @@
 					mux {
 						groups = "spdif_in_a7";
 						function = "spdif_in";
+						bias-disable;
 					};
 				};
 
@@ -541,6 +576,7 @@
 					mux {
 						groups = "spdif_in_a19";
 						function = "spdif_in";
+						bias-disable;
 					};
 				};
 
@@ -548,6 +584,7 @@
 					mux {
 						groups = "spdif_in_a20";
 						function = "spdif_in";
+						bias-disable;
 					};
 				};
 
@@ -555,6 +592,7 @@
 					mux {
 						groups = "spdif_out_a1";
 						function = "spdif_out";
+						bias-disable;
 					};
 				};
 
@@ -562,6 +600,7 @@
 					mux {
 						groups = "spdif_out_a11";
 						function = "spdif_out";
+						bias-disable;
 					};
 				};
 
@@ -569,6 +608,7 @@
 					mux {
 						groups = "spdif_out_a19";
 						function = "spdif_out";
+						bias-disable;
 					};
 				};
 
@@ -576,6 +616,7 @@
 					mux {
 						groups = "spdif_out_a20";
 						function = "spdif_out";
+						bias-disable;
 					};
 				};
 
@@ -583,6 +624,7 @@
 					mux {
 						groups = "spdif_out_z";
 						function = "spdif_out";
+						bias-disable;
 					};
 				};
 
@@ -592,6 +634,7 @@
 							 "spi0_mosi",
 							 "spi0_clk";
 						function = "spi0";
+						bias-disable;
 					};
 				};
 
@@ -599,6 +642,7 @@
 					mux {
 						groups = "spi0_ss0";
 						function = "spi0";
+						bias-disable;
 					};
 				};
 
@@ -606,6 +650,7 @@
 					mux {
 						groups = "spi0_ss1";
 						function = "spi0";
+						bias-disable;
 					};
 				};
 
@@ -613,6 +658,7 @@
 					mux {
 						groups = "spi0_ss2";
 						function = "spi0";
+						bias-disable;
 					};
 				};
 
@@ -622,6 +668,7 @@
 							 "spi1_mosi_a",
 							 "spi1_clk_a";
 						function = "spi1";
+						bias-disable;
 					};
 				};
 
@@ -629,6 +676,7 @@
 					mux {
 						groups = "spi1_ss0_a";
 						function = "spi1";
+						bias-disable;
 					};
 				};
 
@@ -636,6 +684,7 @@
 					mux {
 						groups = "spi1_ss1";
 						function = "spi1";
+						bias-disable;
 					};
 				};
 
@@ -645,6 +694,7 @@
 							 "spi1_mosi_x",
 							 "spi1_clk_x";
 						function = "spi1";
+						bias-disable;
 					};
 				};
 
@@ -652,6 +702,7 @@
 					mux {
 						groups = "spi1_ss0_x";
 						function = "spi1";
+						bias-disable;
 					};
 				};
 
@@ -659,6 +710,7 @@
 					mux {
 						groups = "tdma_din0";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -666,6 +718,7 @@
 					mux {
 						groups = "tdma_dout0_x14";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -673,6 +726,7 @@
 					mux {
 						groups = "tdma_dout0_x15";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -680,6 +734,7 @@
 					mux {
 						groups = "tdma_dout1";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -687,6 +742,7 @@
 					mux {
 						groups = "tdma_din1";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -694,6 +750,7 @@
 					mux {
 						groups = "tdma_fs";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -701,6 +758,7 @@
 					mux {
 						groups = "tdma_fs_slv";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -708,6 +766,7 @@
 					mux {
 						groups = "tdma_sclk";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -715,6 +774,7 @@
 					mux {
 						groups = "tdma_sclk_slv";
 						function = "tdma";
+						bias-disable;
 					};
 				};
 
@@ -722,6 +782,7 @@
 					mux {
 						groups = "tdmb_din0";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -729,6 +790,7 @@
 					mux {
 						groups = "tdmb_din1";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -736,6 +798,7 @@
 					mux {
 						groups = "tdmb_din2";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -743,6 +806,7 @@
 					mux {
 						groups = "tdmb_din3";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -750,6 +814,7 @@
 					mux {
 						groups = "tdmb_dout0";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -757,6 +822,7 @@
 					mux {
 						groups = "tdmb_dout1";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -764,6 +830,7 @@
 					mux {
 						groups = "tdmb_dout2";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -771,6 +838,7 @@
 					mux {
 						groups = "tdmb_dout3";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -778,6 +846,7 @@
 					mux {
 						groups = "tdmb_fs";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -785,6 +854,7 @@
 					mux {
 						groups = "tdmb_fs_slv";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -792,6 +862,7 @@
 					mux {
 						groups = "tdmb_sclk";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -799,6 +870,7 @@
 					mux {
 						groups = "tdmb_sclk_slv";
 						function = "tdmb";
+						bias-disable;
 					};
 				};
 
@@ -806,6 +878,7 @@
 					mux {
 						groups = "tdmc_fs";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -813,6 +886,7 @@
 					mux {
 						groups = "tdmc_fs_slv";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -820,6 +894,7 @@
 					mux {
 						groups = "tdmc_sclk";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -827,6 +902,7 @@
 					mux {
 						groups = "tdmc_sclk_slv";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -834,6 +910,7 @@
 					mux {
 						groups = "tdmc_din0";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -841,6 +918,7 @@
 					mux {
 						groups = "tdmc_din1";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -848,6 +926,7 @@
 					mux {
 						groups = "tdmc_din2";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -855,6 +934,7 @@
 					mux {
 						groups = "tdmc_din3";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -862,6 +942,7 @@
 					mux {
 						groups = "tdmc_dout0";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -869,6 +950,7 @@
 					mux {
 						groups = "tdmc_dout1";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -876,6 +958,7 @@
 					mux {
 						groups = "tdmc_dout2";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -883,6 +966,7 @@
 					mux {
 						groups = "tdmc_dout3";
 						function = "tdmc";
+						bias-disable;
 					};
 				};
 
@@ -891,6 +975,7 @@
 						groups = "uart_tx_a",
 							 "uart_rx_a";
 						function = "uart_a";
+						bias-disable;
 					};
 				};
 
@@ -899,6 +984,7 @@
 						groups = "uart_cts_a",
 							 "uart_rts_a";
 						function = "uart_a";
+						bias-disable;
 					};
 				};
 
@@ -907,6 +993,7 @@
 						groups = "uart_tx_b_x",
 							 "uart_rx_b_x";
 						function = "uart_b";
+						bias-disable;
 					};
 				};
 
@@ -915,6 +1002,7 @@
 						groups = "uart_cts_b_x",
 							 "uart_rts_b_x";
 						function = "uart_b";
+						bias-disable;
 					};
 				};
 
@@ -923,6 +1011,7 @@
 						groups = "uart_tx_b_z",
 							 "uart_rx_b_z";
 						function = "uart_b";
+						bias-disable;
 					};
 				};
 
@@ -931,6 +1020,7 @@
 						groups = "uart_cts_b_z",
 							 "uart_rts_b_z";
 						function = "uart_b";
+						bias-disable;
 					};
 				};
 
@@ -939,6 +1029,7 @@
 						groups = "uart_ao_tx_b_z",
 							 "uart_ao_rx_b_z";
 						function = "uart_ao_b_z";
+						bias-disable;
 					};
 				};
 
@@ -947,6 +1038,7 @@
 						groups = "uart_ao_cts_b_z",
 							 "uart_ao_rts_b_z";
 						function = "uart_ao_b_z";
+						bias-disable;
 					};
 				};
 			};
@@ -1235,6 +1327,7 @@
 					mux {
 						groups = "i2c_ao_sck_4";
 						function = "i2c_ao";
+						bias-disable;
 					};
 				};
 
@@ -1242,6 +1335,7 @@
 					mux {
 						groups = "i2c_ao_sck_8";
 						function = "i2c_ao";
+						bias-disable;
 					};
 				};
 
@@ -1249,6 +1343,7 @@
 					mux {
 						groups = "i2c_ao_sck_10";
 						function = "i2c_ao";
+						bias-disable;
 					};
 				};
 
@@ -1256,6 +1351,7 @@
 					mux {
 						groups = "i2c_ao_sda_5";
 						function = "i2c_ao";
+						bias-disable;
 					};
 				};
 
@@ -1263,6 +1359,7 @@
 					mux {
 						groups = "i2c_ao_sda_9";
 						function = "i2c_ao";
+						bias-disable;
 					};
 				};
 
@@ -1270,6 +1367,7 @@
 					mux {
 						groups = "i2c_ao_sda_11";
 						function = "i2c_ao";
+						bias-disable;
 					};
 				};
 
@@ -1277,6 +1375,7 @@
 					mux {
 						groups = "remote_input_ao";
 						function = "remote_input_ao";
+						bias-disable;
 					};
 				};
 
@@ -1285,6 +1384,7 @@
 						groups = "uart_ao_tx_a",
 							 "uart_ao_rx_a";
 						function = "uart_ao_a";
+						bias-disable;
 					};
 				};
 
@@ -1293,6 +1393,7 @@
 						groups = "uart_ao_cts_a",
 							 "uart_ao_rts_a";
 						function = "uart_ao_a";
+						bias-disable;
 					};
 				};
 
@@ -1301,6 +1402,7 @@
 						groups = "uart_ao_tx_b",
 							 "uart_ao_rx_b";
 						function = "uart_ao_b";
+						bias-disable;
 					};
 				};
 
@@ -1309,6 +1411,7 @@
 						groups = "uart_ao_cts_b",
 							 "uart_ao_rts_b";
 						function = "uart_ao_b";
+						bias-disable;
 					};
 				};
 			};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
index 32ef82321340..6796d250985a 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxbb.dtsi
@@ -81,6 +81,7 @@
 			mux {
 				groups = "uart_tx_ao_a", "uart_rx_ao_a";
 				function = "uart_ao";
+				bias-disable;
 			};
 		};
 
@@ -89,6 +90,7 @@
 				groups = "uart_cts_ao_a",
 				       "uart_rts_ao_a";
 				function = "uart_ao";
+				bias-disable;
 			};
 		};
 
@@ -96,6 +98,7 @@
 			mux {
 				groups = "uart_tx_ao_b", "uart_rx_ao_b";
 				function = "uart_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -104,6 +107,7 @@
 				groups = "uart_cts_ao_b",
 				       "uart_rts_ao_b";
 				function = "uart_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -111,6 +115,7 @@
 			mux {
 				groups = "remote_input_ao";
 				function = "remote_input_ao";
+				bias-disable;
 			};
 		};
 
@@ -119,6 +124,7 @@
 				groups = "i2c_sck_ao",
 				       "i2c_sda_ao";
 				function = "i2c_ao";
+				bias-disable;
 			};
 		};
 
@@ -126,6 +132,7 @@
 			mux {
 				groups = "pwm_ao_a_3";
 				function = "pwm_ao_a_3";
+				bias-disable;
 			};
 		};
 
@@ -133,6 +140,7 @@
 			mux {
 				groups = "pwm_ao_a_6";
 				function = "pwm_ao_a_6";
+				bias-disable;
 			};
 		};
 
@@ -140,6 +148,7 @@
 			mux {
 				groups = "pwm_ao_a_12";
 				function = "pwm_ao_a_12";
+				bias-disable;
 			};
 		};
 
@@ -147,6 +156,7 @@
 			mux {
 				groups = "pwm_ao_b";
 				function = "pwm_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -154,6 +164,7 @@
 			mux {
 				groups = "i2s_am_clk";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -161,6 +172,7 @@
 			mux {
 				groups = "i2s_out_ao_clk";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -168,6 +180,7 @@
 			mux {
 				groups = "i2s_out_lr_clk";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -175,6 +188,7 @@
 			mux {
 				groups = "i2s_out_ch01_ao";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -182,6 +196,7 @@
 			mux {
 				groups = "i2s_out_ch23_ao";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -189,6 +204,7 @@
 			mux {
 				groups = "i2s_out_ch45_ao";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -203,6 +219,7 @@
 			mux {
 				groups = "spdif_out_ao_13";
 				function = "spdif_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -210,6 +227,7 @@
 			mux {
 				groups = "ao_cec";
 				function = "cec_ao";
+				bias-disable;
 			};
 		};
 
@@ -217,6 +235,7 @@
 			mux {
 				groups = "ee_cec";
 				function = "cec_ao";
+				bias-disable;
 			};
 		};
 	};
@@ -390,6 +409,7 @@
 				       "nor_c",
 				       "nor_cs";
 				function = "nor";
+				bias-disable;
 			};
 		};
 
@@ -399,6 +419,7 @@
 					"spi_mosi",
 					"spi_sclk";
 				function = "spi";
+				bias-disable;
 			};
 		};
 
@@ -406,6 +427,7 @@
 			mux {
 				groups = "spi_ss0";
 				function = "spi";
+				bias-disable;
 			};
 		};
 
@@ -455,6 +477,7 @@
 			mux {
 				groups = "sdio_irq";
 				function = "sdio";
+				bias-disable;
 			};
 		};
 
@@ -463,6 +486,7 @@
 				groups = "uart_tx_a",
 				       "uart_rx_a";
 				function = "uart_a";
+				bias-disable;
 			};
 		};
 
@@ -471,6 +495,7 @@
 				groups = "uart_cts_a",
 				       "uart_rts_a";
 				function = "uart_a";
+				bias-disable;
 			};
 		};
 
@@ -479,6 +504,7 @@
 				groups = "uart_tx_b",
 				       "uart_rx_b";
 				function = "uart_b";
+				bias-disable;
 			};
 		};
 
@@ -487,6 +513,7 @@
 				groups = "uart_cts_b",
 				       "uart_rts_b";
 				function = "uart_b";
+				bias-disable;
 			};
 		};
 
@@ -495,6 +522,7 @@
 				groups = "uart_tx_c",
 				       "uart_rx_c";
 				function = "uart_c";
+				bias-disable;
 			};
 		};
 
@@ -503,6 +531,7 @@
 				groups = "uart_cts_c",
 				       "uart_rts_c";
 				function = "uart_c";
+				bias-disable;
 			};
 		};
 
@@ -511,6 +540,7 @@
 				groups = "i2c_sck_a",
 				       "i2c_sda_a";
 				function = "i2c_a";
+				bias-disable;
 			};
 		};
 
@@ -519,6 +549,7 @@
 				groups = "i2c_sck_b",
 				       "i2c_sda_b";
 				function = "i2c_b";
+				bias-disable;
 			};
 		};
 
@@ -527,6 +558,7 @@
 				groups = "i2c_sck_c",
 				       "i2c_sda_c";
 				function = "i2c_c";
+				bias-disable;
 			};
 		};
 
@@ -547,6 +579,7 @@
 				       "eth_txd2",
 				       "eth_txd3";
 				function = "eth";
+				bias-disable;
 			};
 		};
 
@@ -562,6 +595,7 @@
 				       "eth_txd0",
 				       "eth_txd1";
 				function = "eth";
+				bias-disable;
 			};
 		};
 
@@ -569,6 +603,7 @@
 			mux {
 				groups = "pwm_a_x";
 				function = "pwm_a_x";
+				bias-disable;
 			};
 		};
 
@@ -576,6 +611,7 @@
 			mux {
 				groups = "pwm_a_y";
 				function = "pwm_a_y";
+				bias-disable;
 			};
 		};
 
@@ -583,6 +619,7 @@
 			mux {
 				groups = "pwm_b";
 				function = "pwm_b";
+				bias-disable;
 			};
 		};
 
@@ -590,6 +627,7 @@
 			mux {
 				groups = "pwm_d";
 				function = "pwm_d";
+				bias-disable;
 			};
 		};
 
@@ -597,6 +635,7 @@
 			mux {
 				groups = "pwm_e";
 				function = "pwm_e";
+				bias-disable;
 			};
 		};
 
@@ -604,6 +643,7 @@
 			mux {
 				groups = "pwm_f_x";
 				function = "pwm_f_x";
+				bias-disable;
 			};
 		};
 
@@ -611,6 +651,7 @@
 			mux {
 				groups = "pwm_f_y";
 				function = "pwm_f_y";
+				bias-disable;
 			};
 		};
 
@@ -618,6 +659,7 @@
 			mux {
 				groups = "hdmi_hpd";
 				function = "hdmi_hpd";
+				bias-disable;
 			};
 		};
 
@@ -625,6 +667,7 @@
 			mux {
 				groups = "hdmi_sda", "hdmi_scl";
 				function = "hdmi_i2c";
+				bias-disable;
 			};
 		};
 
@@ -632,6 +675,7 @@
 			mux {
 				groups = "i2sout_ch23_y";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -639,6 +683,7 @@
 			mux {
 				groups = "i2sout_ch45_y";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -646,6 +691,7 @@
 			mux {
 				groups = "i2sout_ch67_y";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -653,6 +699,7 @@
 			mux {
 				groups = "spdif_out_y";
 				function = "spdif_out";
+				bias-disable;
 			};
 		};
 	};
diff --git a/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi b/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
index cfeec5579726..ed278097825b 100644
--- a/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
+++ b/arch/arm64/boot/dts/amlogic/meson-gxl.dtsi
@@ -116,6 +116,7 @@
 			mux {
 				groups = "uart_tx_ao_a", "uart_rx_ao_a";
 				function = "uart_ao";
+				bias-disable;
 			};
 		};
 
@@ -124,6 +125,7 @@
 				groups = "uart_cts_ao_a",
 				       "uart_rts_ao_a";
 				function = "uart_ao";
+				bias-disable;
 			};
 		};
 
@@ -131,6 +133,7 @@
 			mux {
 				groups = "uart_tx_ao_b", "uart_rx_ao_b";
 				function = "uart_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -138,6 +141,7 @@
 			mux {
 				groups = "uart_tx_ao_b_0", "uart_rx_ao_b_1";
 				function = "uart_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -146,6 +150,7 @@
 				groups = "uart_cts_ao_b",
 				       "uart_rts_ao_b";
 				function = "uart_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -153,6 +158,7 @@
 			mux {
 				groups = "remote_input_ao";
 				function = "remote_input_ao";
+				bias-disable;
 			};
 		};
 
@@ -161,6 +167,7 @@
 				groups = "i2c_sck_ao",
 				       "i2c_sda_ao";
 				function = "i2c_ao";
+				bias-disable;
 			};
 		};
 
@@ -168,6 +175,7 @@
 			mux {
 				groups = "pwm_ao_a_3";
 				function = "pwm_ao_a";
+				bias-disable;
 			};
 		};
 
@@ -175,6 +183,7 @@
 			mux {
 				groups = "pwm_ao_a_8";
 				function = "pwm_ao_a";
+				bias-disable;
 			};
 		};
 
@@ -182,6 +191,7 @@
 			mux {
 				groups = "pwm_ao_b";
 				function = "pwm_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -189,6 +199,7 @@
 			mux {
 				groups = "pwm_ao_b_6";
 				function = "pwm_ao_b";
+				bias-disable;
 			};
 		};
 
@@ -196,6 +207,7 @@
 			mux {
 				groups = "i2s_out_ch23_ao";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -203,6 +215,7 @@
 			mux {
 				groups = "i2s_out_ch45_ao";
 				function = "i2s_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -210,6 +223,7 @@
 			mux {
 				groups = "spdif_out_ao_6";
 				function = "spdif_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -217,6 +231,7 @@
 			mux {
 				groups = "spdif_out_ao_9";
 				function = "spdif_out_ao";
+				bias-disable;
 			};
 		};
 
@@ -224,6 +239,7 @@
 			mux {
 				groups = "ao_cec";
 				function = "cec_ao";
+				bias-disable;
 			};
 		};
 
@@ -231,6 +247,7 @@
 			mux {
 				groups = "ee_cec";
 				function = "cec_ao";
+				bias-disable;
 			};
 		};
 	};
@@ -337,6 +354,7 @@
 				       "nor_c",
 				       "nor_cs";
 				function = "nor";
+				bias-disable;
 			};
 		};
 
@@ -346,6 +364,7 @@
 					"spi_mosi",
 					"spi_sclk";
 				function = "spi";
+				bias-disable;
 			};
 		};
 
@@ -353,6 +372,7 @@
 			mux {
 				groups = "spi_ss0";
 				function = "spi";
+				bias-disable;
 			};
 		};
 
@@ -402,6 +422,7 @@
 			mux {
 				groups = "sdio_irq";
 				function = "sdio";
+				bias-disable;
 			};
 		};
 
@@ -410,6 +431,7 @@
 				groups = "uart_tx_a",
 				       "uart_rx_a";
 				function = "uart_a";
+				bias-disable;
 			};
 		};
 
@@ -418,6 +440,7 @@
 				groups = "uart_cts_a",
 				       "uart_rts_a";
 				function = "uart_a";
+				bias-disable;
 			};
 		};
 
@@ -426,6 +449,7 @@
 				groups = "uart_tx_b",
 				       "uart_rx_b";
 				function = "uart_b";
+				bias-disable;
 			};
 		};
 
@@ -434,6 +458,7 @@
 				groups = "uart_cts_b",
 				       "uart_rts_b";
 				function = "uart_b";
+				bias-disable;
 			};
 		};
 
@@ -442,6 +467,7 @@
 				groups = "uart_tx_c",
 				       "uart_rx_c";
 				function = "uart_c";
+				bias-disable;
 			};
 		};
 
@@ -450,6 +476,7 @@
 				groups = "uart_cts_c",
 				       "uart_rts_c";
 				function = "uart_c";
+				bias-disable;
 			};
 		};
 
@@ -458,6 +485,7 @@
 				groups = "i2c_sck_a",
 				     "i2c_sda_a";
 				function = "i2c_a";
+				bias-disable;
 			};
 		};
 
@@ -466,6 +494,7 @@
 				groups = "i2c_sck_b",
 				      "i2c_sda_b";
 				function = "i2c_b";
+				bias-disable;
 			};
 		};
 
@@ -474,6 +503,7 @@
 				groups = "i2c_sck_c",
 				      "i2c_sda_c";
 				function = "i2c_c";
+				bias-disable;
 			};
 		};
 
@@ -494,6 +524,7 @@
 				       "eth_txd2",
 				       "eth_txd3";
 				function = "eth";
+				bias-disable;
 			};
 		};
 
@@ -501,6 +532,7 @@
 			mux {
 				groups = "eth_link_led";
 				function = "eth_led";
+				bias-disable;
 			};
 		};
 
@@ -515,6 +547,7 @@
 			mux {
 				groups = "pwm_a";
 				function = "pwm_a";
+				bias-disable;
 			};
 		};
 
@@ -522,6 +555,7 @@
 			mux {
 				groups = "pwm_b";
 				function = "pwm_b";
+				bias-disable;
 			};
 		};
 
@@ -529,6 +563,7 @@
 			mux {
 				groups = "pwm_c";
 				function = "pwm_c";
+				bias-disable;
 			};
 		};
 
@@ -536,6 +571,7 @@
 			mux {
 				groups = "pwm_d";
 				function = "pwm_d";
+				bias-disable;
 			};
 		};
 
@@ -543,6 +579,7 @@
 			mux {
 				groups = "pwm_e";
 				function = "pwm_e";
+				bias-disable;
 			};
 		};
 
@@ -550,6 +587,7 @@
 			mux {
 				groups = "pwm_f_clk";
 				function = "pwm_f";
+				bias-disable;
 			};
 		};
 
@@ -557,6 +595,7 @@
 			mux {
 				groups = "pwm_f_x";
 				function = "pwm_f";
+				bias-disable;
 			};
 		};
 
@@ -564,6 +603,7 @@
 			mux {
 				groups = "hdmi_hpd";
 				function = "hdmi_hpd";
+				bias-disable;
 			};
 		};
 
@@ -571,6 +611,7 @@
 			mux {
 				groups = "hdmi_sda", "hdmi_scl";
 				function = "hdmi_i2c";
+				bias-disable;
 			};
 		};
 
@@ -578,6 +619,7 @@
 			mux {
 				groups = "i2s_am_clk";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -585,6 +627,7 @@
 			mux {
 				groups = "i2s_out_ao_clk";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -592,6 +635,7 @@
 			mux {
 				groups = "i2s_out_lr_clk";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -599,12 +643,14 @@
 			mux {
 				groups = "i2s_out_ch01";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 		i2sout_ch23_z_pins: i2sout_ch23_z {
 			mux {
 				groups = "i2sout_ch23_z";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -612,6 +658,7 @@
 			mux {
 				groups = "i2sout_ch45_z";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -619,6 +666,7 @@
 			mux {
 				groups = "i2sout_ch67_z";
 				function = "i2s_out";
+				bias-disable;
 			};
 		};
 
@@ -626,6 +674,7 @@
 			mux {
 				groups = "spdif_out_h";
 				function = "spdif_out";
+				bias-disable;
 			};
 		};
 	};
-- 
2.19.1

[PATCH v2 4/4] ARM: dts: meson: consistently disable pin bias

[Jerome Brunet]

On Amlogic chipsets, the bias set through pinconf applies to the pad
itself, not only the GPIO function. This means that even when we change
the function of the pad from GPIO to anything else, the bias previously
set still applies.

As we have seen with the eMMC, depending on the bias type and the function,
it may trigger problems.

The underlying issue is that we inherit whatever was left by previous user
of the pad (pinconf, u-boot or the ROM code). As a consequence, the actual
setup we will get is undefined.

There is nothing mentioned in the documentation about pad bias and pinmux
function, however leaving it undefined is not an option.

This change consistently disable the pad bias for every pinmux functions.
It seems to work well, we can only assume that the necessary bias (if any)
is already provided by the pin function itself.

Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
---
 arch/arm/boot/dts/meson8.dtsi   | 12 ++++++++++++
 arch/arm/boot/dts/meson8b.dtsi  |  9 +++++++++
 arch/arm/boot/dts/meson8m2.dtsi |  1 +
 3 files changed, 22 insertions(+)

diff --git a/arch/arm/boot/dts/meson8.dtsi b/arch/arm/boot/dts/meson8.dtsi
index 7162e0ca05b0..08c54cf5420a 100644
--- a/arch/arm/boot/dts/meson8.dtsi
+++ b/arch/arm/boot/dts/meson8.dtsi
@@ -163,6 +163,7 @@
 			mux {
 				groups = "uart_tx_ao_a", "uart_rx_ao_a";
 				function = "uart_ao";
+				bias-disable;
 			};
 		};
 
@@ -170,6 +171,7 @@
 			mux {
 				groups = "i2c_mst_sck_ao", "i2c_mst_sda_ao";
 				function = "i2c_mst_ao";
+				bias-disable;
 			};
 		};
 
@@ -177,6 +179,7 @@
 			mux {
 				groups = "remote_input";
 				function = "remote";
+				bias-disable;
 			};
 		};
 
@@ -184,6 +187,7 @@
 			mux {
 				groups = "pwm_f_ao";
 				function = "pwm_f_ao";
+				bias-disable;
 			};
 		};
 	};
@@ -238,6 +242,7 @@
 				groups = "sd_d0_a", "sd_d1_a", "sd_d2_a",
 					"sd_d3_a", "sd_clk_a", "sd_cmd_a";
 				function = "sd_a";
+				bias-disable;
 			};
 		};
 
@@ -246,6 +251,7 @@
 				groups = "sd_d0_b", "sd_d1_b", "sd_d2_b",
 					"sd_d3_b", "sd_clk_b", "sd_cmd_b";
 				function = "sd_b";
+				bias-disable;
 			};
 		};
 
@@ -254,6 +260,7 @@
 				groups = "sd_d0_c", "sd_d1_c", "sd_d2_c",
 					"sd_d3_c", "sd_clk_c", "sd_cmd_c";
 				function = "sd_c";
+				bias-disable;
 			};
 		};
 
@@ -261,6 +268,7 @@
 			mux {
 				groups = "nor_d", "nor_q", "nor_c", "nor_cs";
 				function = "nor";
+				bias-disable;
 			};
 		};
 
@@ -272,6 +280,7 @@
 					 "eth_rxd1", "eth_rxd0", "eth_mdio",
 					 "eth_mdc";
 				function = "ethernet";
+				bias-disable;
 			};
 		};
 
@@ -279,6 +288,7 @@
 			mux {
 				groups = "pwm_e";
 				function = "pwm_e";
+				bias-disable;
 			};
 		};
 
@@ -287,6 +297,7 @@
 				groups = "uart_tx_a1",
 				       "uart_rx_a1";
 				function = "uart_a";
+				bias-disable;
 			};
 		};
 
@@ -295,6 +306,7 @@
 				groups = "uart_cts_a1",
 				       "uart_rts_a1";
 				function = "uart_a";
+				bias-disable;
 			};
 		};
 	};
diff --git a/arch/arm/boot/dts/meson8b.dtsi b/arch/arm/boot/dts/meson8b.dtsi
index cd1ca9dda126..46b3564a6536 100644
--- a/arch/arm/boot/dts/meson8b.dtsi
+++ b/arch/arm/boot/dts/meson8b.dtsi
@@ -146,6 +146,7 @@
 			mux {
 				groups = "uart_tx_ao_a", "uart_rx_ao_a";
 				function = "uart_ao";
+				bias-disable;
 			};
 		};
 
@@ -153,6 +154,7 @@
 			mux {
 				groups = "remote_input";
 				function = "remote";
+				bias-disable;
 			};
 		};
 	};
@@ -220,6 +222,7 @@
 					 "eth_txd2",
 					 "eth_txd3";
 				function = "ethernet";
+				bias-disable;
 			};
 		};
 
@@ -235,6 +238,7 @@
 					 "eth_mdio_en",
 					 "eth_mdc";
 				function = "ethernet";
+				bias-disable;
 			};
 		};
 
@@ -242,6 +246,7 @@
 			mux {
 				groups = "i2c_sda_a", "i2c_sck_a";
 				function = "i2c_a";
+				bias-disable;
 			};
 		};
 
@@ -250,6 +255,7 @@
 				groups = "sd_d0_b", "sd_d1_b", "sd_d2_b",
 					"sd_d3_b", "sd_clk_b", "sd_cmd_b";
 				function = "sd_b";
+				bias-disable;
 			};
 		};
 
@@ -257,6 +263,7 @@
 			mux {
 				groups = "pwm_c1";
 				function = "pwm_c";
+				bias-disable;
 			};
 		};
 
@@ -265,6 +272,7 @@
 				groups = "uart_tx_b0",
 				       "uart_rx_b0";
 				function = "uart_b";
+				bias-disable;
 			};
 		};
 
@@ -273,6 +281,7 @@
 				groups = "uart_cts_b0",
 				       "uart_rts_b0";
 				function = "uart_b";
+				bias-disable;
 			};
 		};
 	};
diff --git a/arch/arm/boot/dts/meson8m2.dtsi b/arch/arm/boot/dts/meson8m2.dtsi
index 3e1f92273d7b..d1a28c2adac5 100644
--- a/arch/arm/boot/dts/meson8m2.dtsi
+++ b/arch/arm/boot/dts/meson8m2.dtsi
@@ -45,6 +45,7 @@
 				 "eth_rxd1", "eth_rxd0",
 				 "eth_mdio", "eth_mdc";
 			function = "ethernet";
+			bias-disable;
 		};
 	};
 };
-- 
2.19.1

Re: [PATCH v2 4/4] ARM: dts: meson: consistently disable pin bias

[Martin Blumenstingl]

On Fri, Nov 9, 2018 at 3:05 PM Jerome Brunet <jbrunet@baylibre.com> wrote:
>
> On Amlogic chipsets, the bias set through pinconf applies to the pad
> itself, not only the GPIO function. This means that even when we change
> the function of the pad from GPIO to anything else, the bias previously
> set still applies.
>
> As we have seen with the eMMC, depending on the bias type and the function,
> it may trigger problems.
>
> The underlying issue is that we inherit whatever was left by previous user
> of the pad (pinconf, u-boot or the ROM code). As a consequence, the actual
> setup we will get is undefined.
>
> There is nothing mentioned in the documentation about pad bias and pinmux
> function, however leaving it undefined is not an option.
>
> This change consistently disable the pad bias for every pinmux functions.
> It seems to work well, we can only assume that the necessary bias (if any)
> is already provided by the pin function itself.
>
> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
Acked-by: Martin Blumenstingl<martin.blumenstingl@googlemail.com>

my Odroid-C1 still boots fine from SD card and Ethernet (ping) also still works

Kevin, can you please move this patch from your v4.21/dt64 branch to
the v4.21/dt (32-bit) branch?
all other patches from this series are for the 64-bit SoCs, so only
this single patch has to be moved


Thank you!
Regards
Martin

Re: [PATCH v2 4/4] ARM: dts: meson: consistently disable pin bias

[Kevin Hilman]

Martin Blumenstingl <martin.blumenstingl@googlemail.com> writes:

> On Fri, Nov 9, 2018 at 3:05 PM Jerome Brunet <jbrunet@baylibre.com> wrote:
>>
>> On Amlogic chipsets, the bias set through pinconf applies to the pad
>> itself, not only the GPIO function. This means that even when we change
>> the function of the pad from GPIO to anything else, the bias previously
>> set still applies.
>>
>> As we have seen with the eMMC, depending on the bias type and the function,
>> it may trigger problems.
>>
>> The underlying issue is that we inherit whatever was left by previous user
>> of the pad (pinconf, u-boot or the ROM code). As a consequence, the actual
>> setup we will get is undefined.
>>
>> There is nothing mentioned in the documentation about pad bias and pinmux
>> function, however leaving it undefined is not an option.
>>
>> This change consistently disable the pad bias for every pinmux functions.
>> It seems to work well, we can only assume that the necessary bias (if any)
>> is already provided by the pin function itself.
>>
>> Signed-off-by: Jerome Brunet <jbrunet@baylibre.com>
> Acked-by: Martin Blumenstingl<martin.blumenstingl@googlemail.com>
>
> my Odroid-C1 still boots fine from SD card and Ethernet (ping) also still works
>
> Kevin, can you please move this patch from your v4.21/dt64 branch to
> the v4.21/dt (32-bit) branch?
> all other patches from this series are for the 64-bit SoCs, so only
> this single patch has to be moved

Thanks for catching it.

I moved it to the 32-bit branch, and added your ack.

Kevin

Re: [PATCH v2 0/4] ARM: dts: meson: set pinmux bias

[Kevin Hilman]

Jerome Brunet <jbrunet@baylibre.com> writes:

> On Amlogic chipsets, the bias set through pinconf applies to the pad
> itself, not only the GPIO function. This means that even when we change
> the function of the pad from GPIO to anything else, the bias previously
> set still applies.
>
> While trying to boot from SPI, I noticed the eMMC was not working anymore.
> Even if the related eMMC pad are not used by the SPI, the ROM code sets a
> pull-down on the eMMC pad and leaves it that way. This breaks the eMMC
> later on, in both u-boot and Linux.
>
> The underlying issue is that we inherit whatever was left by previous user
> of the pad (pinconf, u-boot or the ROM code). As a consequence, the actual
> setup we get is undefined.
>
> There is nothing mentioned in the documentation about pad bias and pinmux
> function, however leaving it undefined is not an option.
>
> This patchset consistently disable the pad bias for every pinmux functions.
> It seems to work well, we can only assume that the necessary bias (if any)
> is already provided by the pin function itself.
>
> I can't really test every pinmux configuration and it is fairly possible
> I missed something so it would be nice if more people could confirm if
> nothing (new) is broken after applying this series.

I'll queue this up for v4.21/dt64 branch for a bit broader testing.

> One things could be the i2c. Usually the i2c pull-ups are physically
> present on the board but, if they are missing on platform, we may define
> a special pinmux setting with pull-up enabled.
>
> One last gotcha, I recently posted fixups around bias setting to pinctrl
> which have been merged: [0] [1]. These must be applied before applying this
> series, otherwise when requesting 'bias-disable' you'll probably get a
> pull-down instead.

OK, I'll include pinctrl/for-next branch in my 'integ' branch.

Kevin