[PATCH 1/2] MIPS/input: Move RB532 button to GPIO descriptors
Linus Walleij
linusw at kernel.org
Sat Mar 28 08:55:47 PDT 2026
Convert the Mikrotik RouterBoard RB532 to use GPIO descriptors
by defining a software node for the GPIO chip, then register
the button platform device with full info passing the GPIO
as a device property.
This can be used as a base to move more of the RB532 devices
over to passing GPIOs using device properties.
Use the GPIO_ACTIVE_LOW flag and drop the inversion in the
rb532_button_pressed() function.
Signed-off-by: Linus Walleij <linusw at kernel.org>
---
arch/mips/rb532/devices.c | 47 +++++++++++++++++++++++++++++++++------
drivers/input/misc/rb532_button.c | 35 ++++++++++++++++++++++++-----
2 files changed, 69 insertions(+), 13 deletions(-)
diff --git a/arch/mips/rb532/devices.c b/arch/mips/rb532/devices.c
index 4f027efbf27b..3f56d9feb73a 100644
--- a/arch/mips/rb532/devices.c
+++ b/arch/mips/rb532/devices.c
@@ -16,8 +16,10 @@
#include <linux/mtd/mtd.h>
#include <linux/gpio.h>
#include <linux/gpio/machine.h>
+#include <linux/gpio/property.h>
#include <linux/gpio_keys.h>
#include <linux/input.h>
+#include <linux/property.h>
#include <linux/serial_8250.h>
#include <asm/bootinfo.h>
@@ -38,6 +40,10 @@ extern unsigned int idt_cpu_freq;
static struct mpmc_device dev3;
+static const struct software_node rb532_gpio0_node = {
+ .name = "gpio0",
+};
+
void set_latch_u5(unsigned char or_mask, unsigned char nand_mask)
{
unsigned long flags;
@@ -189,11 +195,6 @@ static struct platform_device rb532_led = {
.id = -1,
};
-static struct platform_device rb532_button = {
- .name = "rb532-button",
- .id = -1,
-};
-
static struct resource rb532_wdt_res[] = {
{
.name = "rb532_wdt_res",
@@ -236,11 +237,23 @@ static struct platform_device *rb532_devs[] = {
&nand_slot0,
&cf_slot0,
&rb532_led,
- &rb532_button,
&rb532_uart,
&rb532_wdt
};
+static const struct property_entry rb532_button_properties[] = {
+ PROPERTY_ENTRY_GPIO("button-gpios", &rb532_gpio0_node,
+ GPIO_BTN_S1, GPIO_ACTIVE_LOW),
+ { }
+};
+
+static const struct platform_device_info rb532_button_info __initconst = {
+ .name = "rb532-button",
+ .id = PLATFORM_DEVID_NONE,
+ .properties = rb532_button_properties,
+};
+
+
/* NAND definitions */
#define NAND_CHIP_DELAY 25
@@ -267,6 +280,9 @@ static void __init rb532_nand_setup(void)
static int __init plat_setup_devices(void)
{
+ struct platform_device *pd;
+ int ret;
+
/* Look for the CF card reader */
if (!readl(IDT434_REG_BASE + DEV1MASK))
rb532_devs[2] = NULL; /* disable cf_slot0 at index 2 */
@@ -295,7 +311,24 @@ static int __init plat_setup_devices(void)
rb532_uart_res[0].uartclk = idt_cpu_freq;
gpiod_add_lookup_table(&cf_slot0_gpio_table);
- return platform_add_devices(rb532_devs, ARRAY_SIZE(rb532_devs));
+ ret = platform_add_devices(rb532_devs, ARRAY_SIZE(rb532_devs));
+ if (ret)
+ return ret;
+
+ /*
+ * Stack devices using full info and properties here, after we
+ * register the node for the GPIO chip.
+ */
+ software_node_register(&rb532_gpio0_node);
+
+ pd = platform_device_register_full(&rb532_button_info);
+ ret = PTR_ERR_OR_ZERO(pd);
+ if (ret) {
+ pr_err("failed to create RB532 button device: %d\n", ret);
+ return ret;
+ }
+
+ return 0;
}
#ifdef CONFIG_NET
diff --git a/drivers/input/misc/rb532_button.c b/drivers/input/misc/rb532_button.c
index 190a80e1e2c1..40173bf7a235 100644
--- a/drivers/input/misc/rb532_button.c
+++ b/drivers/input/misc/rb532_button.c
@@ -8,7 +8,7 @@
#include <linux/input.h>
#include <linux/module.h>
#include <linux/platform_device.h>
-#include <linux/gpio.h>
+#include <linux/gpio/consumer.h>
#include <asm/mach-rc32434/gpio.h>
#include <asm/mach-rc32434/rb.h>
@@ -18,6 +18,14 @@
#define RB532_BTN_RATE 100 /* msec */
#define RB532_BTN_KSYM BTN_0
+/**
+ * struct rb532_button - RB532 button information
+ * @gpio: GPIO connected to the button
+ */
+struct rb532_button {
+ struct gpio_desc *gpio;
+};
+
/* The S1 button state is provided by GPIO pin 1. But as this
* pin is also used for uart input as alternate function, the
* operational modes must be switched first:
@@ -31,35 +39,48 @@
* The GPIO value occurs to be inverted, so pin high means
* button is not pressed.
*/
-static bool rb532_button_pressed(void)
+static bool rb532_button_pressed(struct rb532_button *button)
{
int val;
set_latch_u5(0, LO_FOFF);
- gpio_direction_input(GPIO_BTN_S1);
+ gpiod_direction_input(button->gpio);
- val = gpio_get_value(GPIO_BTN_S1);
+ val = gpiod_get_value(button->gpio);
rb532_gpio_set_func(GPIO_BTN_S1);
set_latch_u5(LO_FOFF, 0);
- return !val;
+ return val;
}
static void rb532_button_poll(struct input_dev *input)
{
- input_report_key(input, RB532_BTN_KSYM, rb532_button_pressed());
+ struct rb532_button *button = input_get_drvdata(input);
+
+ input_report_key(input, RB532_BTN_KSYM, rb532_button_pressed(button));
input_sync(input);
}
static int rb532_button_probe(struct platform_device *pdev)
{
+ struct rb532_button *button;
struct input_dev *input;
int error;
+ button = devm_kzalloc(&pdev->dev, sizeof(*button), GFP_KERNEL);
+ if (!button)
+ return -ENOMEM;
+
+ button->gpio = devm_gpiod_get(&pdev->dev, "button", GPIOD_IN);
+ if (IS_ERR(button->gpio))
+ return dev_err_probe(&pdev->dev, PTR_ERR(button->gpio),
+ "error getting button GPIO\n");
+
input = devm_input_allocate_device(&pdev->dev);
if (!input)
return -ENOMEM;
+ input_set_drvdata(input, button);
input->name = "rb532 button";
input->phys = "rb532/button0";
@@ -77,6 +98,8 @@ static int rb532_button_probe(struct platform_device *pdev)
if (error)
return error;
+ platform_set_drvdata(pdev, button);
+
return 0;
}
--
2.53.0
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