Re: [PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
On Mon, Feb 10, 2014 at 11:03:55AM +0100, Wolfram Sang wrote: > Signed-off-by: Wolfram Sang > Cc: devicet...@vger.kernel.org > Cc: linux-arm-ker...@lists.infradead.org Applied to for-current, thanks! signature.asc Description: Digital signature
Re: [PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
On Mon, Feb 10, 2014 at 11:03:55AM +0100, Wolfram Sang wrote: Signed-off-by: Wolfram Sang w...@the-dreams.de Cc: devicet...@vger.kernel.org Cc: linux-arm-ker...@lists.infradead.org Applied to for-current, thanks! signature.asc Description: Digital signature
Re: [PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
> There is now also a means to instantiate I2C devices through > ACPI. This is documented in Documentation/acpi/enumeration.txt. > > Might be worthwhile to reference it from instantiating-devices. > I guess that would be a separate patch though. Yes, it would. Thanks for the pointer! signature.asc Description: Digital signature
Re: [PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
There is now also a means to instantiate I2C devices through ACPI. This is documented in Documentation/acpi/enumeration.txt. Might be worthwhile to reference it from instantiating-devices. I guess that would be a separate patch though. Yes, it would. Thanks for the pointer! signature.asc Description: Digital signature
Re: [PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
Quoting Wolfram Sang : Signed-off-by: Wolfram Sang Cc: devicet...@vger.kernel.org Cc: linux-arm-ker...@lists.infradead.org --- Documentation/i2c/instantiating-devices | 34 +++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices index c70e7a7..6df095a 100644 --- a/Documentation/i2c/instantiating-devices +++ b/Documentation/i2c/instantiating-devices @@ -8,8 +8,8 @@ reason, the kernel code must instantiate I2C devices explicitly. There are several ways to achieve this, depending on the context and requirements. -Method 1: Declare the I2C devices by bus number +Method 1a: Declare the I2C devices by bus number + This method is appropriate when the I2C bus is a system bus as is the case for many embedded systems. On such systems, each I2C bus has a number @@ -51,6 +51,36 @@ The devices will be automatically unbound and destroyed when the I2C bus they sit on goes away (if ever.) +Method 1b: Declare the I2C devices via devicetree +- + Hi Wolfram, There is now also a means to instantiate I2C devices through ACPI. This is documented in Documentation/acpi/enumeration.txt. Might be worthwhile to reference it from instantiating-devices. I guess that would be a separate patch though. Thanks, Guenter -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
[PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
Signed-off-by: Wolfram Sang
Cc: devicet...@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
---
Documentation/i2c/instantiating-devices | 34 +++--
1 file changed, 32 insertions(+), 2 deletions(-)
diff --git a/Documentation/i2c/instantiating-devices
b/Documentation/i2c/instantiating-devices
index c70e7a7..6df095a 100644
--- a/Documentation/i2c/instantiating-devices
+++ b/Documentation/i2c/instantiating-devices
@@ -8,8 +8,8 @@ reason, the kernel code must instantiate I2C devices
explicitly. There are
several ways to achieve this, depending on the context and requirements.
-Method 1: Declare the I2C devices by bus number
+Method 1a: Declare the I2C devices by bus number
+
This method is appropriate when the I2C bus is a system bus as is the case
for many embedded systems. On such systems, each I2C bus has a number
@@ -51,6 +51,36 @@ The devices will be automatically unbound and destroyed when
the I2C bus
they sit on goes away (if ever.)
+Method 1b: Declare the I2C devices via devicetree
+-
+
+This method has the same implications as method 1a. The declaration of I2C
+devices is here done via devicetree as subnodes of the master controller.
+
+Example:
+
+ i2c1: i2c@400a {
+ /* ... master properties skipped ... */
+ clock-frequency = <10>;
+
+ flash@50 {
+ compatible = "atmel,24c256";
+ reg = <0x50>;
+ };
+
+ pca9532: gpio@60 {
+ compatible = "nxp,pca9532";
+ gpio-controller;
+ #gpio-cells = <2>;
+ reg = <0x60>;
+ };
+ };
+
+Here, two devices are attached to the bus using a speed of 100kHz. For
+additional properties which might be needed to set up the device, please refer
+to its devicetree documentation in Documentation/devicetree/bindings/.
+
+
Method 2: Instantiate the devices explicitly
--
1.8.5.1
--
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[PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
Signed-off-by: Wolfram Sang w...@the-dreams.de
Cc: devicet...@vger.kernel.org
Cc: linux-arm-ker...@lists.infradead.org
---
Documentation/i2c/instantiating-devices | 34 +++--
1 file changed, 32 insertions(+), 2 deletions(-)
diff --git a/Documentation/i2c/instantiating-devices
b/Documentation/i2c/instantiating-devices
index c70e7a7..6df095a 100644
--- a/Documentation/i2c/instantiating-devices
+++ b/Documentation/i2c/instantiating-devices
@@ -8,8 +8,8 @@ reason, the kernel code must instantiate I2C devices
explicitly. There are
several ways to achieve this, depending on the context and requirements.
-Method 1: Declare the I2C devices by bus number
+Method 1a: Declare the I2C devices by bus number
+
This method is appropriate when the I2C bus is a system bus as is the case
for many embedded systems. On such systems, each I2C bus has a number
@@ -51,6 +51,36 @@ The devices will be automatically unbound and destroyed when
the I2C bus
they sit on goes away (if ever.)
+Method 1b: Declare the I2C devices via devicetree
+-
+
+This method has the same implications as method 1a. The declaration of I2C
+devices is here done via devicetree as subnodes of the master controller.
+
+Example:
+
+ i2c1: i2c@400a {
+ /* ... master properties skipped ... */
+ clock-frequency = 10;
+
+ flash@50 {
+ compatible = atmel,24c256;
+ reg = 0x50;
+ };
+
+ pca9532: gpio@60 {
+ compatible = nxp,pca9532;
+ gpio-controller;
+ #gpio-cells = 2;
+ reg = 0x60;
+ };
+ };
+
+Here, two devices are attached to the bus using a speed of 100kHz. For
+additional properties which might be needed to set up the device, please refer
+to its devicetree documentation in Documentation/devicetree/bindings/.
+
+
Method 2: Instantiate the devices explicitly
--
1.8.5.1
--
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Please read the FAQ at http://www.tux.org/lkml/
Re: [PATCH 01/17] Documentation: i2c: describe devicetree method for instantiating devices
Quoting Wolfram Sang w...@the-dreams.de: Signed-off-by: Wolfram Sang w...@the-dreams.de Cc: devicet...@vger.kernel.org Cc: linux-arm-ker...@lists.infradead.org --- Documentation/i2c/instantiating-devices | 34 +++-- 1 file changed, 32 insertions(+), 2 deletions(-) diff --git a/Documentation/i2c/instantiating-devices b/Documentation/i2c/instantiating-devices index c70e7a7..6df095a 100644 --- a/Documentation/i2c/instantiating-devices +++ b/Documentation/i2c/instantiating-devices @@ -8,8 +8,8 @@ reason, the kernel code must instantiate I2C devices explicitly. There are several ways to achieve this, depending on the context and requirements. -Method 1: Declare the I2C devices by bus number +Method 1a: Declare the I2C devices by bus number + This method is appropriate when the I2C bus is a system bus as is the case for many embedded systems. On such systems, each I2C bus has a number @@ -51,6 +51,36 @@ The devices will be automatically unbound and destroyed when the I2C bus they sit on goes away (if ever.) +Method 1b: Declare the I2C devices via devicetree +- + Hi Wolfram, There is now also a means to instantiate I2C devices through ACPI. This is documented in Documentation/acpi/enumeration.txt. Might be worthwhile to reference it from instantiating-devices. I guess that would be a separate patch though. Thanks, Guenter -- To unsubscribe from this list: send the line unsubscribe linux-kernel in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
