[U-Boot] [PATCH v2 06/10] PINCTRL: stm32f7: add pin control driver

Vikas Manocha vikas.manocha at st.com
Fri Feb 10 23:11:39 UTC 2017


This driver uses the same pin control binding as that of linux, binding
document of this patch is copied from linux. One addition done is for
GPIO input and output mode configuration which was missing.

Signed-off-by: Vikas Manocha <vikas.manocha at st.com>
---

Changed in v2:
	- added blank lines in code like before return and after
	  variable declaration.
	- remove not used function.
	- changed fixed length array read from DT node to relaxed length read.


 configs/stm32f746-disco_defconfig                  |   3 +
 .../pinctrl/st,stm32-pinctrl.txt                   | 133 +++++++++++++++++++++
 drivers/pinctrl/Kconfig                            |   9 ++
 drivers/pinctrl/Makefile                           |   1 +
 drivers/pinctrl/pinctrl_stm32.c                    | 121 +++++++++++++++++++
 5 files changed, 267 insertions(+)
 create mode 100644 doc/device-tree-bindings/pinctrl/st,stm32-pinctrl.txt
 create mode 100644 drivers/pinctrl/pinctrl_stm32.c

diff --git a/configs/stm32f746-disco_defconfig b/configs/stm32f746-disco_defconfig
index af1449c..e77ebfc 100644
--- a/configs/stm32f746-disco_defconfig
+++ b/configs/stm32f746-disco_defconfig
@@ -39,3 +39,6 @@ CONFIG_STM32_QSPI=y
 CONFIG_OF_LIBFDT_OVERLAY=y
 # CONFIG_EFI_LOADER is not set
 CONFIG_CLK=y
+CONFIG_PINCTRL=y
+# CONFIG_PINCTRL_FULL is not set
+CONFIG_PINCTRL_STM32=y
diff --git a/doc/device-tree-bindings/pinctrl/st,stm32-pinctrl.txt b/doc/device-tree-bindings/pinctrl/st,stm32-pinctrl.txt
new file mode 100644
index 0000000..c41ae91
--- /dev/null
+++ b/doc/device-tree-bindings/pinctrl/st,stm32-pinctrl.txt
@@ -0,0 +1,133 @@
+* STM32 GPIO and Pin Mux/Config controller
+
+STMicroelectronics's STM32 MCUs intregrate a GPIO and Pin mux/config hardware
+controller. It controls the input/output settings on the available pins and
+also provides ability to multiplex and configure the output of various on-chip
+controllers onto these pads.
+
+Pin controller node:
+Required properies:
+ - compatible: value should be one of the following:
+   (a) "st,stm32f429-pinctrl"
+   (b) "st,stm32f746-pinctrl"
+ - #address-cells: The value of this property must be 1
+ - #size-cells	: The value of this property must be 1
+ - ranges	: defines mapping between pin controller node (parent) to
+   gpio-bank node (children).
+ - pins-are-numbered: Specify the subnodes are using numbered pinmux to
+   specify pins.
+
+GPIO controller/bank node:
+Required properties:
+ - gpio-controller : Indicates this device is a GPIO controller
+ - #gpio-cells	  : Should be two.
+			The first cell is the pin number
+			The second one is the polarity:
+				- 0 for active high
+				- 1 for active low
+ - reg		  : The gpio address range, relative to the pinctrl range
+ - clocks	  : clock that drives this bank
+ - st,bank-name	  : Should be a name string for this bank as specified in
+   the datasheet
+
+Optional properties:
+ - reset:	  : Reference to the reset controller
+ - interrupt-parent: phandle of the interrupt parent to which the external
+   GPIO interrupts are forwarded to.
+ - st,syscfg: Should be phandle/offset pair. The phandle to the syscon node
+   which includes IRQ mux selection register, and the offset of the IRQ mux
+   selection register.
+
+Example:
+#include <dt-bindings/pinctrl/stm32f429-pinfunc.h>
+...
+
+	pin-controller {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		compatible = "st,stm32f429-pinctrl";
+		ranges = <0 0x40020000 0x3000>;
+		pins-are-numbered;
+
+		gpioa: gpio at 40020000 {
+			gpio-controller;
+			#gpio-cells = <2>;
+			reg = <0x0 0x400>;
+			resets = <&reset_ahb1 0>;
+			st,bank-name = "GPIOA";
+		};
+		...
+		pin-functions nodes follow...
+	};
+
+Contents of function subnode node:
+----------------------------------
+Subnode format
+A pinctrl node should contain at least one subnode representing the
+pinctrl group available on the machine. Each subnode will list the
+pins it needs, and how they should be configured, with regard to muxer
+configuration, pullups, drive, output high/low and output speed.
+
+    node {
+	pinmux = <PIN_NUMBER_PINMUX>;
+	GENERIC_PINCONFIG;
+    };
+
+Required properties:
+- pinmux: integer array, represents gpio pin number and mux setting.
+  Supported pin number and mux varies for different SoCs, and are defined in
+  dt-bindings/pinctrl/<soc>-pinfunc.h directly.
+  These defines are calculated as:
+    ((port * 16 + line) << 8) | function
+  With:
+    - port: The gpio port index (PA = 0, PB = 1, ..., PK = 11)
+    - line: The line offset within the port (PA0 = 0, PA1 = 1, ..., PA15 = 15)
+    - function: The function number, can be:
+      * 0 : GPIO IN
+      * 1 : Alternate Function 0
+      * 2 : Alternate Function 1
+      * 3 : Alternate Function 2
+      * ...
+      * 16 : Alternate Function 15
+      * 17 : Analog
+      * 18 : GPIO OUT
+
+Optional properties:
+- GENERIC_PINCONFIG: is the generic pinconfig options to use.
+  Available options are:
+   - bias-disable,
+   - bias-pull-down,
+   - bias-pull-up,
+   - drive-push-pull,
+   - drive-open-drain,
+   - output-low
+   - output-high
+   - slew-rate = <x>, with x being:
+       < 0 > : Low speed
+       < 1 > : Medium speed
+       < 2 > : Fast speed
+       < 3 > : High speed
+
+Example:
+
+pin-controller {
+...
+	usart1_pins_a: usart1 at 0 {
+		pins1 {
+			pinmux = <STM32F429_PA9_FUNC_USART1_TX>;
+			bias-disable;
+			drive-push-pull;
+			slew-rate = <0>;
+		};
+		pins2 {
+			pinmux = <STM32F429_PA10_FUNC_USART1_RX>;
+			bias-disable;
+		};
+	};
+};
+
+&usart1 {
+	pinctrl-0 = <&usart1_pins_a>;
+	pinctrl-names = "default";
+	status = "okay";
+};
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index efcb4c0..2dc420c 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -175,6 +175,15 @@ config PIC32_PINCTRL
 	  by a device tree node which contains both GPIO defintion and pin control
 	  functions.
 
+config PINCTRL_STM32
+	bool "ST STM32 pin control driver"
+	depends on DM
+	help
+	  Supports pin multiplexing control on stm32 SoCs. The driver is
+	  controlled by a device tree node which contains both the GPIO
+	  definitions and pin control functions for each available multiplex
+	  function.
+
 endif
 
 source "drivers/pinctrl/meson/Kconfig"
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 512112a..2e23b05 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -16,3 +16,4 @@ obj-$(CONFIG_PIC32_PINCTRL)	+= pinctrl_pic32.o
 obj-$(CONFIG_PINCTRL_EXYNOS)	+= exynos/
 obj-$(CONFIG_PINCTRL_MESON)	+= meson/
 obj-$(CONFIG_PINCTRL_MVEBU)	+= mvebu/
+obj-$(CONFIG_PINCTRL_STM32)	+= pinctrl_stm32.o
diff --git a/drivers/pinctrl/pinctrl_stm32.c b/drivers/pinctrl/pinctrl_stm32.c
new file mode 100644
index 0000000..df38adf
--- /dev/null
+++ b/drivers/pinctrl/pinctrl_stm32.c
@@ -0,0 +1,121 @@
+#include <common.h>
+#include <asm/arch/gpio.h>
+#include <dm.h>
+#include <dm/pinctrl.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static int prep_gpio_dsc(struct stm32_gpio_dsc *gpio_dsc, u32 port_pin)
+{
+	gpio_dsc->port = (port_pin & 0xF000) >> 12;
+	gpio_dsc->pin = (port_pin & 0x0F00) >> 8;
+	debug("%s: GPIO:port= %d, pin= %d\n", __func__, gpio_dsc->port,
+	      gpio_dsc->pin);
+
+	return 0;
+}
+
+static int prep_gpio_ctl(struct stm32_gpio_ctl *gpio_ctl, u32 gpio_fn, int node)
+{
+	gpio_fn &= 0x00FF;
+
+	switch (gpio_fn) {
+	case 0:
+		gpio_ctl->mode = STM32_GPIO_MODE_IN;
+		break;
+	case 1 ... 16:
+		gpio_ctl->mode = STM32_GPIO_MODE_AF;
+		gpio_ctl->af = gpio_fn - 1;
+		break;
+	case 17:
+		gpio_ctl->mode = STM32_GPIO_MODE_AN;
+		break;
+	default:
+		gpio_ctl->mode = STM32_GPIO_MODE_OUT;
+		break;
+	}
+
+	gpio_ctl->speed = fdtdec_get_int(gd->fdt_blob, node, "slew-rate", 0);
+
+	if (fdtdec_get_bool(gd->fdt_blob, node, "drive-open-drain"))
+		gpio_ctl->otype = STM32_GPIO_OTYPE_OD;
+	else
+		gpio_ctl->otype = STM32_GPIO_OTYPE_PP;
+
+	if (fdtdec_get_bool(gd->fdt_blob, node, "bias-pull-up"))
+		gpio_ctl->pupd = STM32_GPIO_PUPD_UP;
+	else if (fdtdec_get_bool(gd->fdt_blob, node, "bias-pull-down"))
+		gpio_ctl->pupd = STM32_GPIO_PUPD_DOWN;
+	else
+		gpio_ctl->pupd = STM32_GPIO_PUPD_NO;
+
+	debug("%s: gpio fn= %d, slew-rate= %x, op type= %x, pull-upd is = %x\n",
+	      __func__,  gpio_fn, gpio_ctl->speed, gpio_ctl->otype,
+	     gpio_ctl->pupd);
+
+	return 0;
+}
+
+static int stm32_pinctrl_set_state_simple(struct udevice *dev,
+					  struct udevice *periph)
+{
+	u32 pin_mux[50];
+	struct fdtdec_phandle_args args;
+	int rv, len;
+
+	/* Get node pinctrl-0 */
+	rv = fdtdec_parse_phandle_with_args(gd->fdt_blob, periph->of_offset,
+					   "pinctrl-0", 0, 0, 0, &args);
+	if (rv)
+		return rv;
+	/*
+	 * check for "pinmux" property in each subnode (e.g. pins1 and pins2 for
+	 * usart1) of pin controller phandle "pinctrl-0"
+	 * */
+	fdt_for_each_subnode(args.node, gd->fdt_blob, args.node) {
+		struct stm32_gpio_dsc gpio_dsc;
+		struct stm32_gpio_ctl gpio_ctl;
+		int i;
+
+		/*
+		 * just to get the length of "pinmux" to allocate correct size
+		 * or memory
+		 * */
+		fdt_get_property(gd->fdt_blob, args.node, "pinmux", &len);
+		len /= 4;
+		debug("%s: no of pinmux entries= %d\n", __func__, len);
+		len = fdtdec_get_int_array_count(gd->fdt_blob, args.node,
+						 "pinmux", pin_mux, len);
+		if (len < 0)
+			return -EINVAL;
+		for (i = 0; i < len; i++) {
+			debug("%s: pinmux = %x\n", __func__, *(pin_mux + i));
+			prep_gpio_dsc(&gpio_dsc, *(pin_mux + i));
+			prep_gpio_ctl(&gpio_ctl, *(pin_mux + i), args.node);
+
+			rv = stm32_gpio_config(&gpio_dsc, &gpio_ctl);
+			debug("%s: rv = %d\n\n", __func__, rv);
+			if (rv)
+				return rv;
+		}
+	}
+
+	return 0;
+}
+
+static struct pinctrl_ops stm32_pinctrl_ops = {
+	.set_state_simple	= stm32_pinctrl_set_state_simple,
+};
+
+static const struct udevice_id stm32_pinctrl_ids[] = {
+	{ .compatible = "st,stm32f746-pinctrl" },
+	{ }
+};
+
+U_BOOT_DRIVER(pinctrl_stm32) = {
+	.name		= "pinctrl_stm32",
+	.id		= UCLASS_PINCTRL,
+	.of_match	= stm32_pinctrl_ids,
+	.ops		= &stm32_pinctrl_ops,
+	.bind		= dm_scan_fdt_dev,
+};
-- 
1.9.1



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