[PATCH v3 06/14] pinctrl: add nexell driver
Stefan Bosch
stefan_b at posteo.net
Mon Jun 29 19:46:38 CEST 2020
Changes in relation to FriendlyARM's U-Boot nanopi2-v2016.01:
- livetree API (dev_read_...) is used instead of fdt one (fdt...).
- doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt added.
Signed-off-by: Stefan Bosch <stefan_b at posteo.net>
---
Changes in v3:
- Kconfig: Missing helps added.
- Changed to livetree API as proposed by patman:
fdt_stringlist_count() --> dev_read_string_count()
fdt_stringlist_get() --> dev_read_string_index()
fdtdec_get_int() --> dev_read_s32_default()
- doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt added.
.../pinctrl/nexell,s5pxx18-pinctrl.txt | 78 ++++++++
drivers/pinctrl/Kconfig | 1 +
drivers/pinctrl/Makefile | 1 +
drivers/pinctrl/nexell/Kconfig | 18 ++
drivers/pinctrl/nexell/Makefile | 7 +
drivers/pinctrl/nexell/pinctrl-nexell.c | 66 +++++++
drivers/pinctrl/nexell/pinctrl-nexell.h | 68 +++++++
drivers/pinctrl/nexell/pinctrl-s5pxx18.c | 220 +++++++++++++++++++++
drivers/pinctrl/nexell/pinctrl-s5pxx18.h | 53 +++++
9 files changed, 512 insertions(+)
create mode 100644 doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt
create mode 100644 drivers/pinctrl/nexell/Kconfig
create mode 100644 drivers/pinctrl/nexell/Makefile
create mode 100644 drivers/pinctrl/nexell/pinctrl-nexell.c
create mode 100644 drivers/pinctrl/nexell/pinctrl-nexell.h
create mode 100644 drivers/pinctrl/nexell/pinctrl-s5pxx18.c
create mode 100644 drivers/pinctrl/nexell/pinctrl-s5pxx18.h
diff --git a/doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt b/doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt
new file mode 100644
index 0000000..115ab53
--- /dev/null
+++ b/doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt
@@ -0,0 +1,78 @@
+Binding for Nexell s5pxx18 pin cotroller
+========================================
+
+Nexell's ARM bases SoC's integrates a GPIO and Pin mux/config hardware
+controller. It controls the input/output settings on the available pads/pins
+and also provides ability to multiplex and configure the output of various
+on-chip controllers onto these pads.
+
+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".
+
+
+Required properties:
+ - compatible: "nexell,s5pxx18-pinctrl"
+ - reg: should be register base and length as documented in the datasheet
+ - interrupts: interrupt specifier for the controller over gpio and alive pins
+
+Example:
+pinctrl_0: pinctrl at c0010000 {
+ compatible = "nexell,s5pxx18-pinctrl";
+ reg = <0xc0010000 0xf000>;
+ u-boot,dm-pre-reloc;
+};
+
+Nexell's pin configuration nodes act as a container for an arbitrary number of
+subnodes. Each of these subnodes represents some desired configuration for a
+pin, a group, or a list of pins or groups. This configuration can include the
+mux function to select on those pin(s)/group(s), and various pin configuration
+parameters.
+
+ Child nodes must be set at least one of the following settings:
+ - pins = Select pins for using this function.
+ - pin-function = Select the function for use in a selected pin.
+ - pin-pull = Pull up/down configuration.
+ - pin-strength = Drive strength configuration.
+
+ Valid values for nexell,pins are:
+ "gpioX-N" : X in {A,B,C,D,E}, N in {0-31}
+ Valid values for nexell,pin-function are:
+ "N" : N in {0-3}.
+ This setting means that the value is different for each pin.
+ Please refer to datasheet.
+ Valid values for nexell,pin-pull are:
+ "N" : 0 - Down, 1 - Up, 2 - Off
+ Valid values for nexell,pin-strength are:
+ "N" : 0,1,2,3
+
+
+Example:
+ - pin settings
+ mmc0_clk: mmc0-clk {
+ pins = "gpioa-29";
+ pin-function = <1>;
+ pin-pull = <2>;
+ pin-strength = <2>;
+ };
+
+ mmc0_cmd: mmc0-cmd {
+ pins = "gpioa-31";
+ pin-function = <1>;
+ pin-pull = <2>;
+ pin-strength = <1>;
+ };
+
+ mmc0_bus4: mmc0-bus-width4 {
+ pins = "gpiob-1, gpiob-3, gpiob-5, gpiob-7";
+ pin-function = <1>;
+ pin-pull = <2>;
+ pin-strength = <1>;
+ };
+
+ - used by client devices
+ mmc0:mmc at ... {
+ pinctrl-names = "default";
+ pinctrl-0 = <&mmc0_clk>, <&mmc0_cmd>, <&mmc0_bus4>;
+ ...
+ };
diff --git a/drivers/pinctrl/Kconfig b/drivers/pinctrl/Kconfig
index 83e39b9..bd2061b 100644
--- a/drivers/pinctrl/Kconfig
+++ b/drivers/pinctrl/Kconfig
@@ -294,6 +294,7 @@ source "drivers/pinctrl/meson/Kconfig"
source "drivers/pinctrl/mscc/Kconfig"
source "drivers/pinctrl/mtmips/Kconfig"
source "drivers/pinctrl/mvebu/Kconfig"
+source "drivers/pinctrl/nexell/Kconfig"
source "drivers/pinctrl/nxp/Kconfig"
source "drivers/pinctrl/renesas/Kconfig"
source "drivers/pinctrl/rockchip/Kconfig"
diff --git a/drivers/pinctrl/Makefile b/drivers/pinctrl/Makefile
index 4f662c4..92cff1b 100644
--- a/drivers/pinctrl/Makefile
+++ b/drivers/pinctrl/Makefile
@@ -21,6 +21,7 @@ obj-$(CONFIG_PINCTRL_MESON) += meson/
obj-$(CONFIG_PINCTRL_MTK) += mediatek/
obj-$(CONFIG_PINCTRL_MSCC) += mscc/
obj-$(CONFIG_ARCH_MVEBU) += mvebu/
+obj-$(CONFIG_ARCH_NEXELL) += nexell/
obj-$(CONFIG_PINCTRL_SINGLE) += pinctrl-single.o
obj-$(CONFIG_PINCTRL_STI) += pinctrl-sti.o
obj-$(CONFIG_PINCTRL_STM32) += pinctrl_stm32.o
diff --git a/drivers/pinctrl/nexell/Kconfig b/drivers/pinctrl/nexell/Kconfig
new file mode 100644
index 0000000..8f1e472
--- /dev/null
+++ b/drivers/pinctrl/nexell/Kconfig
@@ -0,0 +1,18 @@
+if ARCH_NEXELL
+
+config PINCTRL_NEXELL
+ bool "Nexell pinctrl driver"
+ help
+ Support of pin multiplexing and pin configuration for Nexell
+ SoCs.
+
+config PINCTRL_NEXELL_S5PXX18
+ bool "Nexell s5pxx18 SoC pinctrl driver"
+ default y if ARCH_S5P4418 || ARCH_S5P6818
+ depends on ARCH_NEXELL && PINCTRL_FULL
+ select PINCTRL_NEXELL
+ help
+ Support of pin multiplexing and pin configuration for S5P4418
+ and S5P6818 SoC.
+
+endif
diff --git a/drivers/pinctrl/nexell/Makefile b/drivers/pinctrl/nexell/Makefile
new file mode 100644
index 0000000..74df414
--- /dev/null
+++ b/drivers/pinctrl/nexell/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2016 Nexell
+# Bongyu, KOO <freestyle at nexell.co.kr>
+
+obj-$(CONFIG_PINCTRL_NEXELL) += pinctrl-nexell.o
+obj-$(CONFIG_PINCTRL_NEXELL_S5PXX18) += pinctrl-s5pxx18.o
diff --git a/drivers/pinctrl/nexell/pinctrl-nexell.c b/drivers/pinctrl/nexell/pinctrl-nexell.c
new file mode 100644
index 0000000..4518c05
--- /dev/null
+++ b/drivers/pinctrl/nexell/pinctrl-nexell.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Pinctrl driver for Nexell SoCs
+ * (C) Copyright 2016 Nexell
+ * Bongyu, KOO <freestyle at nexell.co.kr>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/io.h>
+#include "pinctrl-nexell.h"
+#include "pinctrl-s5pxx18.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/* given a pin-name, return the address of pin config registers */
+unsigned long pin_to_bank_base(struct udevice *dev, const char *pin_name,
+ u32 *pin)
+{
+ struct nexell_pinctrl_priv *priv = dev_get_priv(dev);
+ const struct nexell_pin_ctrl *pin_ctrl = priv->pin_ctrl;
+ const struct nexell_pin_bank_data *bank_data = pin_ctrl->pin_banks;
+ u32 nr_banks = pin_ctrl->nr_banks, idx = 0;
+ char bank[10];
+
+ /*
+ * The format of the pin name is <bank name>-<pin_number>.
+ * Example: gpioa-4 (gpioa is the bank name and 4 is the pin number)
+ */
+ while (pin_name[idx] != '-') {
+ bank[idx] = pin_name[idx];
+ idx++;
+ }
+ bank[idx] = '\0';
+ *pin = (u32)simple_strtoul(&pin_name[++idx], NULL, 10);
+
+ /* lookup the pin bank data using the pin bank name */
+ for (idx = 0; idx < nr_banks; idx++)
+ if (!strcmp(bank, bank_data[idx].name))
+ break;
+
+ return priv->base + bank_data[idx].offset;
+}
+
+int nexell_pinctrl_probe(struct udevice *dev)
+{
+ struct nexell_pinctrl_priv *priv;
+ fdt_addr_t base;
+
+ priv = dev_get_priv(dev);
+ if (!priv)
+ return -EINVAL;
+
+ base = devfdt_get_addr(dev);
+ if (base == FDT_ADDR_T_NONE)
+ return -EINVAL;
+
+ priv->base = base;
+
+ priv->pin_ctrl = (struct nexell_pin_ctrl *)dev_get_driver_data(dev);
+
+ s5pxx18_pinctrl_init(dev);
+
+ return 0;
+}
diff --git a/drivers/pinctrl/nexell/pinctrl-nexell.h b/drivers/pinctrl/nexell/pinctrl-nexell.h
new file mode 100644
index 0000000..b21eefc
--- /dev/null
+++ b/drivers/pinctrl/nexell/pinctrl-nexell.h
@@ -0,0 +1,68 @@
+/* SPDX-License-Identifier: GPL-2.0+
+ *
+ * Pinctrl driver for Nexell SoCs
+ * (C) Copyright 2016 Nexell
+ * Bongyu, KOO <freestyle at nexell.co.kr>
+ *
+ */
+
+#ifndef __PINCTRL_NEXELL_H_
+#define __PINCTRL_NEXELL_H_
+
+/**
+ * struct nexell_pin_bank_data: represent a controller pin-bank data.
+ * @offset: starting offset of the pin-bank registers.
+ * @nr_pins: number of pins included in this bank.
+ * @name: name to be prefixed for each pin in this pin bank.
+ */
+struct nexell_pin_bank_data {
+ u32 offset;
+ u8 nr_pins;
+ const char *name;
+ u8 type;
+};
+
+#define NEXELL_PIN_BANK(pins, reg, id) \
+ { \
+ .offset = reg, \
+ .nr_pins = pins, \
+ .name = id \
+ }
+
+/**
+ * struct nexell_pin_ctrl: represent a pin controller.
+ * @pin_banks: list of pin banks included in this controller.
+ * @nr_banks: number of pin banks.
+ */
+struct nexell_pin_ctrl {
+ const struct nexell_pin_bank_data *pin_banks;
+ u32 nr_banks;
+};
+
+/**
+ * struct nexell_pinctrl_priv: nexell pin controller driver private data
+ * @pin_ctrl: pin controller bank information.
+ * @base: base address of the pin controller instance.
+ */
+struct nexell_pinctrl_priv {
+ const struct nexell_pin_ctrl *pin_ctrl;
+ unsigned long base;
+};
+
+/**
+ * struct nexell_pinctrl_config_data: configuration for a peripheral.
+ * @offset: offset of the config registers in the controller.
+ * @mask: value of the register to be masked with.
+ * @value: new value to be programmed.
+ */
+struct nexell_pinctrl_config_data {
+ const unsigned int offset;
+ const unsigned int mask;
+ const unsigned int value;
+};
+
+unsigned long pin_to_bank_base(struct udevice *dev, const char *pin_name,
+ u32 *pin);
+int nexell_pinctrl_probe(struct udevice *dev);
+
+#endif /* __PINCTRL_NEXELL_H_ */
diff --git a/drivers/pinctrl/nexell/pinctrl-s5pxx18.c b/drivers/pinctrl/nexell/pinctrl-s5pxx18.c
new file mode 100644
index 0000000..96a2ed3
--- /dev/null
+++ b/drivers/pinctrl/nexell/pinctrl-s5pxx18.c
@@ -0,0 +1,220 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Pinctrl driver for Nexell SoCs
+ * (C) Copyright 2016 Nexell
+ * Bongyu, KOO <freestyle at nexell.co.kr>
+ *
+ * (C) Copyright 2019 Stefan Bosch <stefan_b at posteo.net>
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <dm/pinctrl.h>
+#include <dm/root.h>
+#include "pinctrl-nexell.h"
+#include "pinctrl-s5pxx18.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static void nx_gpio_set_bit(u32 *value, u32 bit, int enable)
+{
+ register u32 newvalue;
+
+ newvalue = *value;
+ newvalue &= ~(1ul << bit);
+ newvalue |= (u32)enable << bit;
+ writel(newvalue, value);
+}
+
+static void nx_gpio_set_bit2(u32 *value, u32 bit, u32 bit_value)
+{
+ register u32 newvalue = *value;
+
+ newvalue = (u32)(newvalue & ~(3ul << (bit * 2)));
+ newvalue = (u32)(newvalue | (bit_value << (bit * 2)));
+
+ writel(newvalue, value);
+}
+
+static int nx_gpio_open_module(void *base)
+{
+ writel(0xFFFFFFFF, base + GPIOX_SLEW_DISABLE_DEFAULT);
+ writel(0xFFFFFFFF, base + GPIOX_DRV1_DISABLE_DEFAULT);
+ writel(0xFFFFFFFF, base + GPIOX_DRV0_DISABLE_DEFAULT);
+ writel(0xFFFFFFFF, base + GPIOX_PULLSEL_DISABLE_DEFAULT);
+ writel(0xFFFFFFFF, base + GPIOX_PULLENB_DISABLE_DEFAULT);
+ return true;
+}
+
+static void nx_gpio_set_pad_function(void *base, u32 pin, u32 padfunc)
+{
+ u32 reg = (pin / 16) ? GPIOX_ALTFN1 : GPIOX_ALTFN0;
+
+ nx_gpio_set_bit2(base + reg, pin % 16, padfunc);
+}
+
+static void nx_gpio_set_drive_strength(void *base, u32 pin, u32 drv)
+{
+ nx_gpio_set_bit(base + GPIOX_DRV1, pin, (int)(((u32)drv >> 0) & 0x1));
+ nx_gpio_set_bit(base + GPIOX_DRV0, pin, (int)(((u32)drv >> 1) & 0x1));
+}
+
+static void nx_gpio_set_pull_mode(void *base, u32 pin, u32 mode)
+{
+ if (mode == nx_gpio_pull_off) {
+ nx_gpio_set_bit(base + GPIOX_PULLENB, pin, false);
+ nx_gpio_set_bit(base + GPIOX_PULLSEL, pin, false);
+ } else {
+ nx_gpio_set_bit(base + GPIOX_PULLSEL,
+ pin, (mode & 1 ? true : false));
+ nx_gpio_set_bit(base + GPIOX_PULLENB, pin, true);
+ }
+}
+
+static void nx_alive_set_pullup(void *base, u32 pin, bool enable)
+{
+ u32 PULLUP_MASK;
+
+ PULLUP_MASK = (1UL << pin);
+ if (enable)
+ writel(PULLUP_MASK, base + ALIVE_PADPULLUPSET);
+ else
+ writel(PULLUP_MASK, base + ALIVE_PADPULLUPRST);
+}
+
+static int s5pxx18_pinctrl_gpio_init(struct udevice *dev)
+{
+ struct nexell_pinctrl_priv *priv = dev_get_priv(dev);
+ const struct nexell_pin_ctrl *ctrl = priv->pin_ctrl;
+ unsigned long reg = priv->base;
+ int i;
+
+ for (i = 0; i < ctrl->nr_banks - 1; i++) /* except alive bank */
+ nx_gpio_open_module((void *)(reg + ctrl->pin_banks[i].offset));
+
+ return 0;
+}
+
+static int s5pxx18_pinctrl_alive_init(struct udevice *dev)
+{
+ struct nexell_pinctrl_priv *priv = dev_get_priv(dev);
+ const struct nexell_pin_ctrl *ctrl = priv->pin_ctrl;
+ unsigned long reg = priv->base;
+
+ reg += ctrl->pin_banks[ctrl->nr_banks - 1].offset;
+
+ writel(1, reg + ALIVE_PWRGATE);
+ return 0;
+}
+
+int s5pxx18_pinctrl_init(struct udevice *dev)
+{
+ s5pxx18_pinctrl_gpio_init(dev);
+ s5pxx18_pinctrl_alive_init(dev);
+
+ return 0;
+}
+
+static int is_pin_alive(const char *name)
+{
+ return !strncmp(name, "alive", 5);
+}
+
+/**
+ * s5pxx18_pinctrl_set_state: configure a pin state.
+ * dev: the pinctrl device to be configured.
+ * config: the state to be configured.
+ */
+static int s5pxx18_pinctrl_set_state(struct udevice *dev,
+ struct udevice *config)
+{
+ unsigned int count, idx, pin;
+ unsigned int pinfunc, pinpud, pindrv;
+ unsigned long reg;
+ const char *name;
+ int ret;
+
+ /*
+ * refer to the following document for the pinctrl bindings
+ * doc/device-tree-bindings/pinctrl/nexell,s5pxx18-pinctrl.txt
+ */
+ count = dev_read_string_count(config, "pins");
+
+ if (count <= 0)
+ return -EINVAL;
+
+ pinfunc = dev_read_s32_default(config, "pin-function", -1);
+ pinpud = dev_read_s32_default(config, "pin-pull", -1);
+ pindrv = dev_read_s32_default(config, "pin-strength", -1);
+
+ for (idx = 0; idx < count; idx++) {
+ ret = dev_read_string_index(config, "pins", idx, &name);
+ if (ret)
+ return ret;
+ if (!name)
+ continue;
+ reg = pin_to_bank_base(dev, name, &pin);
+
+ if (is_pin_alive(name)) {
+ /* pin pull up/down */
+ if (pinpud != -1)
+ nx_alive_set_pullup((void *)reg, pin,
+ pinpud & 1);
+ continue;
+ }
+
+ /* pin function */
+ if (pinfunc != -1)
+ nx_gpio_set_pad_function((void *)reg, pin, pinfunc);
+
+ /* pin pull up/down/off */
+ if (pinpud != -1)
+ nx_gpio_set_pull_mode((void *)reg, pin, pinpud);
+
+ /* pin drive strength */
+ if (pindrv != -1)
+ nx_gpio_set_drive_strength((void *)reg, pin, pindrv);
+ }
+
+ return 0;
+}
+
+static struct pinctrl_ops s5pxx18_pinctrl_ops = {
+ .set_state = s5pxx18_pinctrl_set_state,
+};
+
+/* pin banks of s5pxx18 pin-controller */
+static const struct nexell_pin_bank_data s5pxx18_pin_banks[] = {
+ NEXELL_PIN_BANK(32, 0xA000, "gpioa"),
+ NEXELL_PIN_BANK(32, 0xB000, "gpiob"),
+ NEXELL_PIN_BANK(32, 0xC000, "gpioc"),
+ NEXELL_PIN_BANK(32, 0xD000, "gpiod"),
+ NEXELL_PIN_BANK(32, 0xE000, "gpioe"),
+ NEXELL_PIN_BANK(6, 0x0800, "alive"),
+};
+
+const struct nexell_pin_ctrl s5pxx18_pin_ctrl[] = {
+ {
+ /* pin-controller data */
+ .pin_banks = s5pxx18_pin_banks,
+ .nr_banks = ARRAY_SIZE(s5pxx18_pin_banks),
+ },
+};
+
+static const struct udevice_id s5pxx18_pinctrl_ids[] = {
+ { .compatible = "nexell,s5pxx18-pinctrl",
+ .data = (ulong)s5pxx18_pin_ctrl },
+ { }
+};
+
+U_BOOT_DRIVER(pinctrl_s5pxx18) = {
+ .name = "pinctrl_s5pxx18",
+ .id = UCLASS_PINCTRL,
+ .of_match = s5pxx18_pinctrl_ids,
+ .priv_auto_alloc_size = sizeof(struct nexell_pinctrl_priv),
+ .ops = &s5pxx18_pinctrl_ops,
+ .probe = nexell_pinctrl_probe,
+ .flags = DM_FLAG_PRE_RELOC
+};
diff --git a/drivers/pinctrl/nexell/pinctrl-s5pxx18.h b/drivers/pinctrl/nexell/pinctrl-s5pxx18.h
new file mode 100644
index 0000000..843a00b
--- /dev/null
+++ b/drivers/pinctrl/nexell/pinctrl-s5pxx18.h
@@ -0,0 +1,53 @@
+/* SPDX-License-Identifier: GPL-2.0+
+ *
+ * Pinctrl driver for Nexell SoCs
+ * (C) Copyright 2016 Nexell
+ * Bongyu, KOO <freestyle at nexell.co.kr>
+ */
+
+#ifndef __PINCTRL_S5PXX18_H_
+#define __PINCTRL_S5PXX18_H_
+
+#include <linux/types.h>
+#include <asm/io.h>
+
+#define GPIOX_ALTFN0 0x20
+#define GPIOX_ALTFN1 0x24
+#define GPIOX_DRV1 0x48
+#define GPIOX_DRV0 0x50
+#define GPIOX_PULLSEL 0x58
+#define GPIOX_PULLENB 0x60
+
+#define GPIOX_SLEW_DISABLE_DEFAULT 0x44
+#define GPIOX_DRV1_DISABLE_DEFAULT 0x4C
+#define GPIOX_DRV0_DISABLE_DEFAULT 0x54
+#define GPIOX_PULLSEL_DISABLE_DEFAULT 0x5C
+#define GPIOX_PULLENB_DISABLE_DEFAULT 0x64
+
+#define ALIVE_PWRGATE 0x0
+#define ALIVE_PADPULLUPRST 0x80
+#define ALIVE_PADPULLUPSET 0x84
+#define ALIVE_PADPULLUPREAD 0x88
+
+enum {
+ nx_gpio_padfunc_0 = 0ul,
+ nx_gpio_padfunc_1 = 1ul,
+ nx_gpio_padfunc_2 = 2ul,
+ nx_gpio_padfunc_3 = 3ul
+};
+
+enum {
+ nx_gpio_drvstrength_0 = 0ul,
+ nx_gpio_drvstrength_1 = 1ul,
+ nx_gpio_drvstrength_2 = 2ul,
+ nx_gpio_drvstrength_3 = 3ul
+};
+
+enum {
+ nx_gpio_pull_down = 0ul,
+ nx_gpio_pull_up = 1ul,
+ nx_gpio_pull_off = 2ul
+};
+
+int s5pxx18_pinctrl_init(struct udevice *dev);
+#endif /* __PINCTRL_S5PXX18_H_ */
--
1.9.1
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