kernel: add support for max6370 watchdog via GPIO

[openwrt/openwrt.git] / target / linux / generic / pending-5.10 / 111-watchdog-max63xx_wdt-Add-support-for-specifying-WDI-.patch

diff --git a/target/linux/generic/pending-5.10/111-watchdog-max63xx_wdt-Add-support-for-specifying-WDI-.patch b/target/linux/generic/pending-5.10/111-watchdog-max63xx_wdt-Add-support-for-specifying-WDI-.patch
new file mode 100644 (file)
index 0000000..d2e134a
--- /dev/null
+++ b/target/linux/generic/pending-5.10/111-watchdog-max63xx_wdt-Add-support-for-specifying-WDI-.patch
@@ -0,0 +1,75 @@
+From bd1b9f66d5134e518419f4c4dacf1884c1616983 Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
+Date: Thu, 28 Apr 2022 11:13:23 +0200
+Subject: [PATCH] watchdog: max63xx_wdt: Add support for specifying WDI logic
+ via GPIO
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+On some boards is WDI logic of max6370 chip connected via GPIO.
+So extend max63xx_wdt driver to allow specifying WDI logic via GPIO.
+
+Signed-off-by: Pali Rohár <pali@kernel.org>
+---
+ drivers/watchdog/max63xx_wdt.c | 24 ++++++++++++++++++++++++
+ 1 file changed, 24 insertions(+)
+
+--- a/drivers/watchdog/max63xx_wdt.c
++++ b/drivers/watchdog/max63xx_wdt.c
+@@ -26,6 +26,7 @@
+ #include <linux/spinlock.h>
+ #include <linux/io.h>
+ #include <linux/slab.h>
++#include <linux/gpio/consumer.h>
+ 
+ #define DEFAULT_HEARTBEAT 60
+ #define MAX_HEARTBEAT     60
+@@ -52,6 +53,9 @@ struct max63xx_wdt {
+       void __iomem *base;
+       spinlock_t lock;
+ 
++      /* GPIOs */
++      struct gpio_desc *gpio_wdi;
++
+       /* WDI and WSET bits write access routines */
+       void (*ping)(struct max63xx_wdt *wdt);
+       void (*set)(struct max63xx_wdt *wdt, u8 set);
+@@ -157,6 +161,17 @@ static const struct watchdog_info max63x
+       .identity = "max63xx Watchdog",
+ };
+ 
++static void max63xx_gpio_ping(struct max63xx_wdt *wdt)
++{
++      spin_lock(&wdt->lock);
++
++      gpiod_set_value(wdt->gpio_wdi, 1);
++      udelay(1);
++      gpiod_set_value(wdt->gpio_wdi, 0);
++
++      spin_unlock(&wdt->lock);
++}
++
+ static void max63xx_mmap_ping(struct max63xx_wdt *wdt)
+ {
+       u8 val;
+@@ -221,10 +236,19 @@ static int max63xx_wdt_probe(struct plat
+               return -EINVAL;
+       }
+ 
++      wdt->gpio_wdi = devm_gpiod_get(dev, NULL, GPIOD_FLAGS_BIT_DIR_OUT);
++      if (IS_ERR(wdt->gpio_wdi) && PTR_ERR(wdt->gpio_wdi) != -ENOENT)
++              return dev_err_probe(dev, PTR_ERR(wdt->gpio_wdi),
++                                   "unable to request gpio: %ld\n",
++                                   PTR_ERR(wdt->gpio_wdi));
++
+       err = max63xx_mmap_init(pdev, wdt);
+       if (err)
+               return err;
+ 
++      if (!IS_ERR(wdt->gpio_wdi))
++              wdt->ping = max63xx_gpio_ping;
++
+       platform_set_drvdata(pdev, &wdt->wdd);
+       watchdog_set_drvdata(&wdt->wdd, wdt);
+