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authorLinus Torvalds2012-12-11 11:21:33 -0800
committerLinus Torvalds2012-12-11 11:21:33 -0800
commit505cbedab9c7c565957e64af6348e5d84acd510e (patch)
tree4855caf82c434629432e22f03c96892d73383ba2 /Documentation
parenta8936db7c2d9ef7f8e080d629301e448291f3b75 (diff)
parent7c8f86a451fe8c010eb93c62d4d69727ccdbe435 (diff)
Merge tag 'pinctrl-for-v3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl
Pull pinctrl changes from Linus Walleij: "These are the first and major pinctrl changes for the v3.8 merge cycle. Some of this is used as merge base for other trees so I better be early on the trigger. As can be seen from the diffstat the major changes are: - A big conversion of the AT91 pinctrl driver and the associated ACKed platform changes under arch/arm/max-at91 and its device trees. This has been coordinated with the AT91 maintainers to go in through the pinctrl tree. - A larger chunk of changes to the SPEAr drivers and the addition of the "plgpio" driver for the SPEAr as well. - The removal of the remnants of the Nomadik driver from the arch/arm tree and fusion of that into the Nomadik driver and platform data header files. - Some local movement in the Marvell MVEBU drivers, these now have their own subdirectory. - The addition of a chunk of code to gpiolib under drivers/gpio to register gpio-to-pin range mappings from the GPIO side of things. This has been requested by Grant Likely and is now implemented, it is particularly useful for device tree work. Then we have incremental updates all over the place, many of these are cleanups and fixes from Axel Lin who has done a great job of removing minor mistakes and compilation annoyances." * tag 'pinctrl-for-v3.8' of git://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-pinctrl: (114 commits) ARM: mmp: select PINCTRL for ARCH_MMP pinctrl: Drop selecting PINCONF for MMP2, PXA168 and PXA910 pinctrl: pinctrl-single: Fix error check condition pinctrl: SPEAr: Update error check for unsigned variables gpiolib: Fix use after free in gpiochip_add_pin_range gpiolib: rename pin range arguments pinctrl: single: support gpio request and free pinctrl: generic: add input schmitt disable parameter pinctrl/u300/coh901: stop spawning pinctrl from GPIO pinctrl/u300/coh901: let the gpio_chip register the range pinctrl: add function to retrieve range from pin gpiolib: return any error code from range creation pinctrl: make range registration defer properly gpiolib: rename find_pinctrl_* gpiolib: let gpiochip_add_pin_range() specify offset ARM: at91: pm9g45: add mmc support ARM: at91: Animeo IP: add mmc support ARM: at91: dt: add mmc pinctrl for Atmel reference boards ARM: at91: dt: at91sam9: add mmc pinctrl support ARM: at91/dts: add nodes for atmel hsmci controllers for atmel boards ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/devicetree/bindings/arm/atmel-at91.txt6
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio.txt36
-rw-r--r--Documentation/devicetree/bindings/gpio/gpio_atmel.txt5
-rw-r--r--Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt141
-rw-r--r--Documentation/gpio.txt42
-rw-r--r--Documentation/pinctrl.txt7
6 files changed, 236 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/arm/atmel-at91.txt b/Documentation/devicetree/bindings/arm/atmel-at91.txt
index d187e9f7cf1c..1196290082d1 100644
--- a/Documentation/devicetree/bindings/arm/atmel-at91.txt
+++ b/Documentation/devicetree/bindings/arm/atmel-at91.txt
@@ -7,6 +7,12 @@ PIT Timer required properties:
- interrupts: Should contain interrupt for the PIT which is the IRQ line
shared across all System Controller members.
+System Timer (ST) required properties:
+- compatible: Should be "atmel,at91rm9200-st"
+- reg: Should contain registers location and length
+- interrupts: Should contain interrupt for the ST which is the IRQ line
+ shared across all System Controller members.
+
TC/TCLIB Timer required properties:
- compatible: Should be "atmel,<chip>-tcb".
<chip> can be "at91rm9200" or "at91sam9x5"
diff --git a/Documentation/devicetree/bindings/gpio/gpio.txt b/Documentation/devicetree/bindings/gpio/gpio.txt
index 4e16ba4feab0..a33628759d36 100644
--- a/Documentation/devicetree/bindings/gpio/gpio.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio.txt
@@ -75,4 +75,40 @@ Example of two SOC GPIO banks defined as gpio-controller nodes:
gpio-controller;
};
+2.1) gpio-controller and pinctrl subsystem
+------------------------------------------
+gpio-controller on a SOC might be tightly coupled with the pinctrl
+subsystem, in the sense that the pins can be used by other functions
+together with optional gpio feature.
+
+While the pin allocation is totally managed by the pin ctrl subsystem,
+gpio (under gpiolib) is still maintained by gpio drivers. It may happen
+that different pin ranges in a SoC is managed by different gpio drivers.
+
+This makes it logical to let gpio drivers announce their pin ranges to
+the pin ctrl subsystem and call 'pinctrl_request_gpio' in order to
+request the corresponding pin before any gpio usage.
+
+For this, the gpio controller can use a pinctrl phandle and pins to
+announce the pinrange to the pin ctrl subsystem. For example,
+
+ qe_pio_e: gpio-controller@1460 {
+ #gpio-cells = <2>;
+ compatible = "fsl,qe-pario-bank-e", "fsl,qe-pario-bank";
+ reg = <0x1460 0x18>;
+ gpio-controller;
+ gpio-ranges = <&pinctrl1 20 10>, <&pinctrl2 50 20>;
+
+ }
+
+where,
+ &pinctrl1 and &pinctrl2 is the phandle to the pinctrl DT node.
+
+ Next values specify the base pin and number of pins for the range
+ handled by 'qe_pio_e' gpio. In the given example from base pin 20 to
+ pin 29 under pinctrl1 and pin 50 to pin 69 under pinctrl2 is handled
+ by this gpio controller.
+
+The pinctrl node must have "#gpio-range-cells" property to show number of
+arguments to pass with phandle from gpio controllers node.
diff --git a/Documentation/devicetree/bindings/gpio/gpio_atmel.txt b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt
index 66efc804806a..85f8c0d084fa 100644
--- a/Documentation/devicetree/bindings/gpio/gpio_atmel.txt
+++ b/Documentation/devicetree/bindings/gpio/gpio_atmel.txt
@@ -9,6 +9,10 @@ Required properties:
unused).
- gpio-controller: Marks the device node as a GPIO controller.
+optional properties:
+- #gpio-lines: Number of gpio if absent 32.
+
+
Example:
pioA: gpio@fffff200 {
compatible = "atmel,at91rm9200-gpio";
@@ -16,5 +20,6 @@ Example:
interrupts = <2 4>;
#gpio-cells = <2>;
gpio-controller;
+ #gpio-lines = <19>;
};
diff --git a/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
new file mode 100644
index 000000000000..3a268127b054
--- /dev/null
+++ b/Documentation/devicetree/bindings/pinctrl/atmel,at91-pinctrl.txt
@@ -0,0 +1,141 @@
+* Atmel AT91 Pinmux Controller
+
+The AT91 Pinmux Controler, enables the IC
+to share one PAD to several functional blocks. The sharing is done by
+multiplexing the PAD input/output signals. For each PAD there are up to
+8 muxing options (called periph modes). Since different modules require
+different PAD settings (like pull up, keeper, etc) the contoller controls
+also the PAD settings parameters.
+
+Please refer to pinctrl-bindings.txt in this directory for details of the
+common pinctrl bindings used by client devices, including the meaning of the
+phrase "pin configuration node".
+
+Atmel AT91 pin configuration node is a node of a group of pins which can be
+used for a specific device or function. This node represents both mux and config
+of the pins in that group. The 'pins' selects the function mode(also named pin
+mode) this pin can work on and the 'config' configures various pad settings
+such as pull-up, multi drive, etc.
+
+Required properties for iomux controller:
+- compatible: "atmel,at91rm9200-pinctrl"
+- atmel,mux-mask: array of mask (periph per bank) to describe if a pin can be
+ configured in this periph mode. All the periph and bank need to be describe.
+
+How to create such array:
+
+Each column will represent the possible peripheral of the pinctrl
+Each line will represent a pio bank
+
+Take an example on the 9260
+Peripheral: 2 ( A and B)
+Bank: 3 (A, B and C)
+=>
+
+ /* A B */
+ 0xffffffff 0xffc00c3b /* pioA */
+ 0xffffffff 0x7fff3ccf /* pioB */
+ 0xffffffff 0x007fffff /* pioC */
+
+For each peripheral/bank we will descibe in a u32 if a pin can can be
+configured in it by putting 1 to the pin bit (1 << pin)
+
+Let's take the pioA on peripheral B
+From the datasheet Table 10-2.
+Peripheral B
+PA0 MCDB0
+PA1 MCCDB
+PA2
+PA3 MCDB3
+PA4 MCDB2
+PA5 MCDB1
+PA6
+PA7
+PA8
+PA9
+PA10 ETX2
+PA11 ETX3
+PA12
+PA13
+PA14
+PA15
+PA16
+PA17
+PA18
+PA19
+PA20
+PA21
+PA22 ETXER
+PA23 ETX2
+PA24 ETX3
+PA25 ERX2
+PA26 ERX3
+PA27 ERXCK
+PA28 ECRS
+PA29 ECOL
+PA30 RXD4
+PA31 TXD4
+
+=> 0xffc00c3b
+
+Required properties for pin configuration node:
+- atmel,pins: 4 integers array, represents a group of pins mux and config
+ setting. The format is atmel,pins = <PIN_BANK PIN_BANK_NUM PERIPH CONFIG>.
+ The PERIPH 0 means gpio.
+
+Bits used for CONFIG:
+PULL_UP (1 << 0): indicate this pin need a pull up.
+MULTIDRIVE (1 << 1): indicate this pin need to be configured as multidrive.
+DEGLITCH (1 << 2): indicate this pin need deglitch.
+PULL_DOWN (1 << 3): indicate this pin need a pull down.
+DIS_SCHMIT (1 << 4): indicate this pin need to disable schmit trigger.
+DEBOUNCE (1 << 16): indicate this pin need debounce.
+DEBOUNCE_VAL (0x3fff << 17): debounce val.
+
+NOTE:
+Some requirements for using atmel,at91rm9200-pinctrl binding:
+1. We have pin function node defined under at91 controller node to represent
+ what pinmux functions this SoC supports.
+2. The driver can use the function node's name and pin configuration node's
+ name describe the pin function and group hierarchy.
+ For example, Linux at91 pinctrl driver takes the function node's name
+ as the function name and pin configuration node's name as group name to
+ create the map table.
+3. Each pin configuration node should have a phandle, devices can set pins
+ configurations by referring to the phandle of that pin configuration node.
+4. The gpio controller must be describe in the pinctrl simple-bus.
+
+Examples:
+
+pinctrl@fffff400 {
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges;
+ compatible = "atmel,at91rm9200-pinctrl", "simple-bus";
+ reg = <0xfffff400 0x600>;
+
+ atmel,mux-mask = <
+ /* A B */
+ 0xffffffff 0xffc00c3b /* pioA */
+ 0xffffffff 0x7fff3ccf /* pioB */
+ 0xffffffff 0x007fffff /* pioC */
+ >;
+
+ /* shared pinctrl settings */
+ dbgu {
+ pinctrl_dbgu: dbgu-0 {
+ atmel,pins =
+ <1 14 0x1 0x0 /* PB14 periph A */
+ 1 15 0x1 0x1>; /* PB15 periph with pullup */
+ };
+ };
+};
+
+dbgu: serial@fffff200 {
+ compatible = "atmel,at91sam9260-usart";
+ reg = <0xfffff200 0x200>;
+ interrupts = <1 4 7>;
+ pinctrl-names = "default";
+ pinctrl-0 = <&pinctrl_dbgu>;
+ status = "disabled";
+};
diff --git a/Documentation/gpio.txt b/Documentation/gpio.txt
index e08a883de36e..77a1d11af723 100644
--- a/Documentation/gpio.txt
+++ b/Documentation/gpio.txt
@@ -439,6 +439,48 @@ slower clock delays the rising edge of SCK, and the I2C master adjusts its
signaling rate accordingly.
+GPIO controllers and the pinctrl subsystem
+------------------------------------------
+
+A GPIO controller on a SOC might be tightly coupled with the pinctrl
+subsystem, in the sense that the pins can be used by other functions
+together with an optional gpio feature. We have already covered the
+case where e.g. a GPIO controller need to reserve a pin or set the
+direction of a pin by calling any of:
+
+pinctrl_request_gpio()
+pinctrl_free_gpio()
+pinctrl_gpio_direction_input()
+pinctrl_gpio_direction_output()
+
+But how does the pin control subsystem cross-correlate the GPIO
+numbers (which are a global business) to a certain pin on a certain
+pin controller?
+
+This is done by registering "ranges" of pins, which are essentially
+cross-reference tables. These are described in
+Documentation/pinctrl.txt
+
+While the pin allocation is totally managed by the pinctrl subsystem,
+gpio (under gpiolib) is still maintained by gpio drivers. It may happen
+that different pin ranges in a SoC is managed by different gpio drivers.
+
+This makes it logical to let gpio drivers announce their pin ranges to
+the pin ctrl subsystem before it will call 'pinctrl_request_gpio' in order
+to request the corresponding pin to be prepared by the pinctrl subsystem
+before any gpio usage.
+
+For this, the gpio controller can register its pin range with pinctrl
+subsystem. There are two ways of doing it currently: with or without DT.
+
+For with DT support refer to Documentation/devicetree/bindings/gpio/gpio.txt.
+
+For non-DT support, user can call gpiochip_add_pin_range() with appropriate
+parameters to register a range of gpio pins with a pinctrl driver. For this
+exact name string of pinctrl device has to be passed as one of the
+argument to this routine.
+
+
What do these conventions omit?
===============================
One of the biggest things these conventions omit is pin multiplexing, since
diff --git a/Documentation/pinctrl.txt b/Documentation/pinctrl.txt
index 3b4ee5328868..da40efbef6ec 100644
--- a/Documentation/pinctrl.txt
+++ b/Documentation/pinctrl.txt
@@ -364,6 +364,9 @@ will get an pin number into its handled number range. Further it is also passed
the range ID value, so that the pin controller knows which range it should
deal with.
+Calling pinctrl_add_gpio_range from pinctrl driver is DEPRECATED. Please see
+section 2.1 of Documentation/devicetree/bindings/gpio/gpio.txt on how to bind
+pinctrl and gpio drivers.
PINMUX interfaces
=================
@@ -1193,4 +1196,6 @@ foo_switch()
...
}
-The above has to be done from process context.
+The above has to be done from process context. The reservation of the pins
+will be done when the state is activated, so in effect one specific pin
+can be used by different functions at different times on a running system.