[PATCH 1/4] ARM: dts: ux500: Disable I2C/SPI buses by default

[PATCH 1/4] ARM: dts: ux500: Disable I2C/SPI buses by default

[Stephan Gerhold]

At the moment, all 5 I2C and 6 SPI buses are probed and exposed
to user-space by default - even if they are not muxed to any pins
on the board. This means that user-space sees an I2C/SPI bus that
cannot be actually used properly.

In some cases this was used to put the corresponding pins into
a low power sleep mode - but even then the pins first need to be
configured by the board-specific device tree part.

Avoid exposing unconfigured devices to user-space by disabling
the I2C/SPI buses by default. Enable them in the board device trees
when needed.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
 arch/arm/boot/dts/ste-dbx5x0.dtsi     | 22 ++++++++++++++++++++++
 arch/arm/boot/dts/ste-href.dtsi       |  4 ++++
 arch/arm/boot/dts/ste-hrefprev60.dtsi |  1 +
 arch/arm/boot/dts/ste-snowball.dts    |  5 +++++
 4 files changed, 32 insertions(+)

diff --git a/arch/arm/boot/dts/ste-dbx5x0.dtsi b/arch/arm/boot/dts/ste-dbx5x0.dtsi
index a53657b83288..899368aa6ff7 100644
--- a/arch/arm/boot/dts/ste-dbx5x0.dtsi
+++ b/arch/arm/boot/dts/ste-dbx5x0.dtsi
@@ -646,6 +646,8 @@
 			clocks = <&prcc_kclk 3 3>, <&prcc_pclk 3 3>;
 			clock-names = "i2cclk", "apb_pclk";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		i2c@80122000 {
@@ -662,6 +664,8 @@
 			clocks = <&prcc_kclk 1 2>, <&prcc_pclk 1 2>;
 			clock-names = "i2cclk", "apb_pclk";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		i2c@80128000 {
@@ -678,6 +682,8 @@
 			clocks = <&prcc_kclk 1 6>, <&prcc_pclk 1 6>;
 			clock-names = "i2cclk", "apb_pclk";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		i2c@80110000 {
@@ -694,6 +700,8 @@
 			clocks = <&prcc_kclk 2 0>, <&prcc_pclk 2 0>;
 			clock-names = "i2cclk", "apb_pclk";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		i2c@8012a000 {
@@ -710,6 +718,8 @@
 			clocks = <&prcc_kclk 1 9>, <&prcc_pclk 1 10>;
 			clock-names = "i2cclk", "apb_pclk";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		spi@80002000 {
@@ -724,6 +734,8 @@
 			       <&dma 8 0 0x0>; /* Logical - MemToDev */
 			dma-names = "rx", "tx";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		spi@80003000 {
@@ -738,6 +750,8 @@
 			       <&dma 9 0 0x0>; /* Logical - MemToDev */
 			dma-names = "rx", "tx";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		spi@8011a000 {
@@ -753,6 +767,8 @@
 			       <&dma 0 0 0x0>; /* Logical - MemToDev */
 			dma-names = "rx", "tx";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		spi@80112000 {
@@ -768,6 +784,8 @@
 			       <&dma 35 0 0x0>; /* Logical - MemToDev */
 			dma-names = "rx", "tx";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		spi@80111000 {
@@ -783,6 +801,8 @@
 			       <&dma 33 0 0x0>; /* Logical - MemToDev */
 			dma-names = "rx", "tx";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		spi@80129000 {
@@ -798,6 +818,8 @@
 			       <&dma 40 0 0x0>; /* Logical - MemToDev */
 			dma-names = "rx", "tx";
 			power-domains = <&pm_domains DOMAIN_VAPE>;
+
+			status = "disabled";
 		};
 
 		ux500_serial0: uart@80120000 {
diff --git a/arch/arm/boot/dts/ste-href.dtsi b/arch/arm/boot/dts/ste-href.dtsi
index 7613a40421d5..5eafd5d8a8cd 100644
--- a/arch/arm/boot/dts/ste-href.dtsi
+++ b/arch/arm/boot/dts/ste-href.dtsi
@@ -39,18 +39,21 @@
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c0_a_1_default>;
 			pinctrl-1 = <&i2c0_a_1_sleep>;
+			status = "okay";
 		};
 
 		i2c@80122000 {
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c1_b_2_default>;
 			pinctrl-1 = <&i2c1_b_2_sleep>;
+			status = "okay";
 		};
 
 		i2c@80128000 {
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c2_b_2_default>;
 			pinctrl-1 = <&i2c2_b_2_sleep>;
+			status = "okay";
 			lp5521@33 {
 				compatible = "national,lp5521";
 				reg = <0x33>;
@@ -98,6 +101,7 @@
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c3_c_2_default>;
 			pinctrl-1 = <&i2c3_c_2_sleep>;
+			status = "okay";
 		};
 
 		/* ST6G3244ME level translator for 1.8/2.9 V */
diff --git a/arch/arm/boot/dts/ste-hrefprev60.dtsi b/arch/arm/boot/dts/ste-hrefprev60.dtsi
index a036defdf164..937f942f0961 100644
--- a/arch/arm/boot/dts/ste-hrefprev60.dtsi
+++ b/arch/arm/boot/dts/ste-hrefprev60.dtsi
@@ -58,6 +58,7 @@
 			 */
 			pinctrl-names = "default";
 			pinctrl-0 = <&ssp0_hrefprev60_mode>;
+			status = "okay";
 		};
 
 		// External Micro SD slot
diff --git a/arch/arm/boot/dts/ste-snowball.dts b/arch/arm/boot/dts/ste-snowball.dts
index 8b80dcdf6e5b..ce136412b6da 100644
--- a/arch/arm/boot/dts/ste-snowball.dts
+++ b/arch/arm/boot/dts/ste-snowball.dts
@@ -307,18 +307,21 @@
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c0_a_1_default>;
 			pinctrl-1 = <&i2c0_a_1_sleep>;
+			status = "okay";
 		};
 
 		i2c@80122000 {
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c1_b_2_default>;
 			pinctrl-1 = <&i2c1_b_2_sleep>;
+			status = "okay";
 		};
 
 		i2c@80128000 {
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c2_b_2_default>;
 			pinctrl-1 = <&i2c2_b_2_sleep>;
+			status = "okay";
 			lsm303dlh@18 {
 				/* Accelerometer */
 				compatible = "st,lsm303dlh-accel";
@@ -369,11 +372,13 @@
 			pinctrl-names = "default","sleep";
 			pinctrl-0 = <&i2c3_c_2_default>;
 			pinctrl-1 = <&i2c3_c_2_sleep>;
+			status = "okay";
 		};
 
 		spi@80002000 {
 			pinctrl-names = "default";
 			pinctrl-0 = <&ssp0_snowball_mode>;
+			status = "okay";
 		};
 
 		prcmu@80157000 {
-- 
2.24.0

[PATCH 2/4] ARM: dts: ux500: Add aliases for I2C and SPI buses

[Stephan Gerhold]

Now that we disable the I2C/SPI buses by default, is is even more
important to assign aliases to the I2C/SPI device nodes.
Otherwise, enabling/disabling one of them will potentially change
all device IDs, e.g. i2c2 will be named i2c-0 if it is the only
enabled I2C bus.

Add aliases for the I2C and SPI buses to avoid this.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
 arch/arm/boot/dts/ste-dbx5x0.dtsi | 35 +++++++++++++++++++++----------
 1 file changed, 24 insertions(+), 11 deletions(-)

diff --git a/arch/arm/boot/dts/ste-dbx5x0.dtsi b/arch/arm/boot/dts/ste-dbx5x0.dtsi
index 899368aa6ff7..ed91232a118a 100644
--- a/arch/arm/boot/dts/ste-dbx5x0.dtsi
+++ b/arch/arm/boot/dts/ste-dbx5x0.dtsi
@@ -13,6 +13,19 @@
 	#address-cells = <1>;
 	#size-cells = <1>;
 
+	/* This stablilizes the device enumeration */
+	aliases {
+		i2c0 = &i2c0;
+		i2c1 = &i2c1;
+		i2c2 = &i2c2;
+		i2c3 = &i2c3;
+		i2c4 = &i2c4;
+		spi0 = &spi0;
+		spi1 = &spi1;
+		spi2 = &spi2;
+		spi3 = &spi3;
+	};
+
 	chosen {
 	};
 
@@ -633,7 +646,7 @@
 			};
 		};
 
-		i2c@80004000 {
+		i2c0: i2c@80004000 {
 			compatible = "stericsson,db8500-i2c", "st,nomadik-i2c", "arm,primecell";
 			reg = <0x80004000 0x1000>;
 			interrupts = <GIC_SPI 21 IRQ_TYPE_LEVEL_HIGH>;
@@ -650,7 +663,7 @@
 			status = "disabled";
 		};
 
-		i2c@80122000 {
+		i2c1: i2c@80122000 {
 			compatible = "stericsson,db8500-i2c", "st,nomadik-i2c", "arm,primecell";
 			reg = <0x80122000 0x1000>;
 			interrupts = <GIC_SPI 22 IRQ_TYPE_LEVEL_HIGH>;
@@ -668,7 +681,7 @@
 			status = "disabled";
 		};
 
-		i2c@80128000 {
+		i2c2: i2c@80128000 {
 			compatible = "stericsson,db8500-i2c", "st,nomadik-i2c", "arm,primecell";
 			reg = <0x80128000 0x1000>;
 			interrupts = <GIC_SPI 55 IRQ_TYPE_LEVEL_HIGH>;
@@ -686,7 +699,7 @@
 			status = "disabled";
 		};
 
-		i2c@80110000 {
+		i2c3: i2c@80110000 {
 			compatible = "stericsson,db8500-i2c", "st,nomadik-i2c", "arm,primecell";
 			reg = <0x80110000 0x1000>;
 			interrupts = <GIC_SPI 12 IRQ_TYPE_LEVEL_HIGH>;
@@ -704,7 +717,7 @@
 			status = "disabled";
 		};
 
-		i2c@8012a000 {
+		i2c4: i2c@8012a000 {
 			compatible = "stericsson,db8500-i2c", "st,nomadik-i2c", "arm,primecell";
 			reg = <0x8012a000 0x1000>;
 			interrupts = <GIC_SPI 51 IRQ_TYPE_LEVEL_HIGH>;
@@ -722,7 +735,7 @@
 			status = "disabled";
 		};
 
-		spi@80002000 {
+		ssp0: spi@80002000 {
 			compatible = "arm,pl022", "arm,primecell";
 			reg = <0x80002000 0x1000>;
 			interrupts = <GIC_SPI 14 IRQ_TYPE_LEVEL_HIGH>;
@@ -738,7 +751,7 @@
 			status = "disabled";
 		};
 
-		spi@80003000 {
+		ssp1: spi@80003000 {
 			compatible = "arm,pl022", "arm,primecell";
 			reg = <0x80003000 0x1000>;
 			interrupts = <GIC_SPI 52 IRQ_TYPE_LEVEL_HIGH>;
@@ -754,7 +767,7 @@
 			status = "disabled";
 		};
 
-		spi@8011a000 {
+		spi0: spi@8011a000 {
 			compatible = "arm,pl022", "arm,primecell";
 			reg = <0x8011a000 0x1000>;
 			interrupts = <GIC_SPI 8 IRQ_TYPE_LEVEL_HIGH>;
@@ -771,7 +784,7 @@
 			status = "disabled";
 		};
 
-		spi@80112000 {
+		spi1: spi@80112000 {
 			compatible = "arm,pl022", "arm,primecell";
 			reg = <0x80112000 0x1000>;
 			interrupts = <GIC_SPI 96 IRQ_TYPE_LEVEL_HIGH>;
@@ -788,7 +801,7 @@
 			status = "disabled";
 		};
 
-		spi@80111000 {
+		spi2: spi@80111000 {
 			compatible = "arm,pl022", "arm,primecell";
 			reg = <0x80111000 0x1000>;
 			interrupts = <GIC_SPI 6 IRQ_TYPE_LEVEL_HIGH>;
@@ -805,7 +818,7 @@
 			status = "disabled";
 		};
 
-		spi@80129000 {
+		spi3: spi@80129000 {
 			compatible = "arm,pl022", "arm,primecell";
 			reg = <0x80129000 0x1000>;
 			interrupts = <GIC_SPI 49 IRQ_TYPE_LEVEL_HIGH>;
-- 
2.24.0

[PATCH 3/4] ARM: dts: ux500: Move serial aliases to ste-dbx5x0.dtsi

[Stephan Gerhold]

Now that we have aliases for I2C and SPI in ste-dbx5x0.dtsi,
it does not make much sense to keep only the aliases for UART
separately in each board device tree.

Considering that all boards set the same aliases for the serial
ports there is no reason to keep them separated either.

Move them to ste-dbx5x0.dtsi and remove the aliases from the
board-specific device tree parts.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
 arch/arm/boot/dts/ste-dbx5x0.dtsi           | 3 +++
 arch/arm/boot/dts/ste-hrefprev60-stuib.dts  | 7 -------
 arch/arm/boot/dts/ste-hrefprev60-tvk.dts    | 7 -------
 arch/arm/boot/dts/ste-hrefv60plus-stuib.dts | 7 -------
 arch/arm/boot/dts/ste-hrefv60plus-tvk.dts   | 7 -------
 arch/arm/boot/dts/ste-snowball.dts          | 7 -------
 6 files changed, 3 insertions(+), 35 deletions(-)

diff --git a/arch/arm/boot/dts/ste-dbx5x0.dtsi b/arch/arm/boot/dts/ste-dbx5x0.dtsi
index ed91232a118a..841934093c3b 100644
--- a/arch/arm/boot/dts/ste-dbx5x0.dtsi
+++ b/arch/arm/boot/dts/ste-dbx5x0.dtsi
@@ -24,6 +24,9 @@
 		spi1 = &spi1;
 		spi2 = &spi2;
 		spi3 = &spi3;
+		serial0 = &ux500_serial0;
+		serial1 = &ux500_serial1;
+		serial2 = &ux500_serial2;
 	};
 
 	chosen {
diff --git a/arch/arm/boot/dts/ste-hrefprev60-stuib.dts b/arch/arm/boot/dts/ste-hrefprev60-stuib.dts
index b78be5f4c212..d2405133860a 100644
--- a/arch/arm/boot/dts/ste-hrefprev60-stuib.dts
+++ b/arch/arm/boot/dts/ste-hrefprev60-stuib.dts
@@ -13,13 +13,6 @@
 	model = "ST-Ericsson HREF (pre-v60) and ST UIB";
 	compatible = "st-ericsson,mop500", "st-ericsson,u8500";
 
-	/* This stablilizes the serial port enumeration */
-	aliases {
-		serial0 = &ux500_serial0;
-		serial1 = &ux500_serial1;
-		serial2 = &ux500_serial2;
-	};
-
 	soc {
 		/* Reset line for the BU21013 touchscreen */
 		i2c@80110000 {
diff --git a/arch/arm/boot/dts/ste-hrefprev60-tvk.dts b/arch/arm/boot/dts/ste-hrefprev60-tvk.dts
index 60eed262d920..54b0f8282b2c 100644
--- a/arch/arm/boot/dts/ste-hrefprev60-tvk.dts
+++ b/arch/arm/boot/dts/ste-hrefprev60-tvk.dts
@@ -10,11 +10,4 @@
 / {
 	model = "ST-Ericsson HREF (pre-v60) and TVK1281618 UIB";
 	compatible = "st-ericsson,mop500", "st-ericsson,u8500";
-
-	/* This stablilizes the serial port enumeration */
-	aliases {
-		serial0 = &ux500_serial0;
-		serial1 = &ux500_serial1;
-		serial2 = &ux500_serial2;
-	};
 };
diff --git a/arch/arm/boot/dts/ste-hrefv60plus-stuib.dts b/arch/arm/boot/dts/ste-hrefv60plus-stuib.dts
index 9be513aad549..36163c0b5267 100644
--- a/arch/arm/boot/dts/ste-hrefv60plus-stuib.dts
+++ b/arch/arm/boot/dts/ste-hrefv60plus-stuib.dts
@@ -15,13 +15,6 @@
 	model = "ST-Ericsson HREF (v60+) and ST UIB";
 	compatible = "st-ericsson,hrefv60+", "st-ericsson,u8500";
 
-	/* This stablilizes the serial port enumeration */
-	aliases {
-		serial0 = &ux500_serial0;
-		serial1 = &ux500_serial1;
-		serial2 = &ux500_serial2;
-	};
-
 	soc {
 		/* Reset line for the BU21013 touchscreen */
 		i2c@80110000 {
diff --git a/arch/arm/boot/dts/ste-hrefv60plus-tvk.dts b/arch/arm/boot/dts/ste-hrefv60plus-tvk.dts
index 73ea3100f186..cf59e9bb9a74 100644
--- a/arch/arm/boot/dts/ste-hrefv60plus-tvk.dts
+++ b/arch/arm/boot/dts/ste-hrefv60plus-tvk.dts
@@ -12,11 +12,4 @@
 / {
 	model = "ST-Ericsson HREF (v60+) and TVK1281618 UIB";
 	compatible = "st-ericsson,hrefv60+", "st-ericsson,u8500";
-
-	/* This stablilizes the serial port enumeration */
-	aliases {
-		serial0 = &ux500_serial0;
-		serial1 = &ux500_serial1;
-		serial2 = &ux500_serial2;
-	};
 };
diff --git a/arch/arm/boot/dts/ste-snowball.dts b/arch/arm/boot/dts/ste-snowball.dts
index ce136412b6da..f8dec3976c91 100644
--- a/arch/arm/boot/dts/ste-snowball.dts
+++ b/arch/arm/boot/dts/ste-snowball.dts
@@ -12,13 +12,6 @@
 	model = "Calao Systems Snowball platform with device tree";
 	compatible = "calaosystems,snowball-a9500", "st-ericsson,u9500";
 
-	/* This stablilizes the serial port enumeration */
-	aliases {
-		serial0 = &ux500_serial0;
-		serial1 = &ux500_serial1;
-		serial2 = &ux500_serial2;
-	};
-
 	memory {
 		device_type = "memory";
 		reg = <0x00000000 0x20000000>;
-- 
2.24.0

[PATCH 4/4] ARM: dts: ux500: Remove ux500_ prefix from ux500_serial* labels

[Stephan Gerhold]

ux500_serial{0,1,2} are the only labels with ux500_ prefix in
ste-dbx5x0.dtsi, the other labels (gpio0, msp, ...) do not use
any prefix. Remove it for consistency.

Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
---
 arch/arm/boot/dts/ste-dbx5x0.dtsi | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/arch/arm/boot/dts/ste-dbx5x0.dtsi b/arch/arm/boot/dts/ste-dbx5x0.dtsi
index 841934093c3b..d4a55369452d 100644
--- a/arch/arm/boot/dts/ste-dbx5x0.dtsi
+++ b/arch/arm/boot/dts/ste-dbx5x0.dtsi
@@ -24,9 +24,9 @@
 		spi1 = &spi1;
 		spi2 = &spi2;
 		spi3 = &spi3;
-		serial0 = &ux500_serial0;
-		serial1 = &ux500_serial1;
-		serial2 = &ux500_serial2;
+		serial0 = &serial0;
+		serial1 = &serial1;
+		serial2 = &serial2;
 	};
 
 	chosen {
@@ -838,7 +838,7 @@
 			status = "disabled";
 		};
 
-		ux500_serial0: uart@80120000 {
+		serial0: uart@80120000 {
 			compatible = "arm,pl011", "arm,primecell";
 			reg = <0x80120000 0x1000>;
 			interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>;
@@ -853,7 +853,7 @@
 			status = "disabled";
 		};
 
-		ux500_serial1: uart@80121000 {
+		serial1: uart@80121000 {
 			compatible = "arm,pl011", "arm,primecell";
 			reg = <0x80121000 0x1000>;
 			interrupts = <GIC_SPI 19 IRQ_TYPE_LEVEL_HIGH>;
@@ -868,7 +868,7 @@
 			status = "disabled";
 		};
 
-		ux500_serial2: uart@80007000 {
+		serial2: uart@80007000 {
 			compatible = "arm,pl011", "arm,primecell";
 			reg = <0x80007000 0x1000>;
 			interrupts = <GIC_SPI 26 IRQ_TYPE_LEVEL_HIGH>;
-- 
2.24.0

Re: [PATCH 1/4] ARM: dts: ux500: Disable I2C/SPI buses by default

[Linus Walleij]

On Mon, Nov 25, 2019 at 6:05 PM Stephan Gerhold <stephan@gerhold.net> wrote:

> At the moment, all 5 I2C and 6 SPI buses are probed and exposed
> to user-space by default - even if they are not muxed to any pins
> on the board. This means that user-space sees an I2C/SPI bus that
> cannot be actually used properly.
>
> In some cases this was used to put the corresponding pins into
> a low power sleep mode - but even then the pins first need to be
> configured by the board-specific device tree part.
>
> Avoid exposing unconfigured devices to user-space by disabling
> the I2C/SPI buses by default. Enable them in the board device trees
> when needed.
>
> Signed-off-by: Stephan Gerhold <stephan@gerhold.net>

All 4 patches applied and pushed to ux500-dts for v5.6!

Yours,
Linus Walleij