target/linux/generic/pending-6.6/111-watchdog-max63xx_wdt-Add-support-for-specifying-WDI-.patch

   1 From bd1b9f66d5134e518419f4c4dacf1884c1616983 Mon Sep 17 00:00:00 2001
   2 From: =?UTF-8?q?Pali=20Roh=C3=A1r?= <pali@kernel.org>
   3 Date: Thu, 28 Apr 2022 11:13:23 +0200
   4 Subject: [PATCH] watchdog: max63xx_wdt: Add support for specifying WDI logic
   5  via GPIO
   6 MIME-Version: 1.0
   7 Content-Type: text/plain; charset=UTF-8
   8 Content-Transfer-Encoding: 8bit
   9
  10 On some boards is WDI logic of max6370 chip connected via GPIO.
  11 So extend max63xx_wdt driver to allow specifying WDI logic via GPIO.
  12
  13 Signed-off-by: Pali Rohár <pali@kernel.org>
  14 ---
  15  drivers/watchdog/max63xx_wdt.c | 24 ++++++++++++++++++++++++
  16  1 file changed, 24 insertions(+)
  17
  18 --- a/drivers/watchdog/max63xx_wdt.c
  19 +++ b/drivers/watchdog/max63xx_wdt.c
  20 @@ -24,6 +24,7 @@
  21  #include <linux/io.h>
  22  #include <linux/slab.h>
  23  #include <linux/property.h>
  24 +#include <linux/gpio/consumer.h>
  25
  26  #define DEFAULT_HEARTBEAT 60
  27  #define MAX_HEARTBEAT     60
  28 @@ -50,6 +51,9 @@ struct max63xx_wdt {
  29         void __iomem *base;
  30         spinlock_t lock;
  31
  32 +       /* GPIOs */
  33 +       struct gpio_desc *gpio_wdi;
  34 +
  35         /* WDI and WSET bits write access routines */
  36         void (*ping)(struct max63xx_wdt *wdt);
  37         void (*set)(struct max63xx_wdt *wdt, u8 set);
  38 @@ -155,6 +159,17 @@ static const struct watchdog_info max63x
  39         .identity = "max63xx Watchdog",
  40  };
  41
  42 +static void max63xx_gpio_ping(struct max63xx_wdt *wdt)
  43 +{
  44 +       spin_lock(&wdt->lock);
  45 +
  46 +       gpiod_set_value(wdt->gpio_wdi, 1);
  47 +       udelay(1);
  48 +       gpiod_set_value(wdt->gpio_wdi, 0);
  49 +
  50 +       spin_unlock(&wdt->lock);
  51 +}
  52 +
  53  static void max63xx_mmap_ping(struct max63xx_wdt *wdt)
  54  {
  55         u8 val;
  56 @@ -222,10 +237,19 @@ static int max63xx_wdt_probe(struct plat
  57                 return -EINVAL;
  58         }
  59
  60 +       wdt->gpio_wdi = devm_gpiod_get(dev, NULL, GPIOD_FLAGS_BIT_DIR_OUT);
  61 +       if (IS_ERR(wdt->gpio_wdi) && PTR_ERR(wdt->gpio_wdi) != -ENOENT)
  62 +               return dev_err_probe(dev, PTR_ERR(wdt->gpio_wdi),
  63 +                                    "unable to request gpio: %ld\n",
  64 +                                    PTR_ERR(wdt->gpio_wdi));
  65 +
  66         err = max63xx_mmap_init(pdev, wdt);
  67         if (err)
  68                 return err;
  69
  70 +       if (!IS_ERR(wdt->gpio_wdi))
  71 +               wdt->ping = max63xx_gpio_ping;
  72 +
  73         platform_set_drvdata(pdev, &wdt->wdd);
  74         watchdog_set_drvdata(&wdt->wdd, wdt);
  75