watchdog: max63xx_wdt: Add device tree probing

This adds device tree probing to the MAX63xx driver so it can be
instantiated from the device tree. We use the generic fwnode-based
method to get to the match data and clean up by constifying the
functions as the match is indeed a const.

Cc: Marc Zyngier <maz@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20210714153314.1004147-2-linus.walleij@linaro.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>

diff --git a/drivers/watchdog/max63xx_wdt.c b/drivers/watchdog/max63xx_wdt.c
index 3a899628a83474d503a4c320021dee5af6485161..9e1541cfae0d89729e8fccf2c4529f18233c608f 100644 (file)
--- 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/property.h>
 
 #define DEFAULT_HEARTBEAT 60
 #define MAX_HEARTBEAT     60
@@ -99,8 +100,8 @@ static const struct max63xx_timeout max6373_table[] = {
        { },
 };
 
-static struct max63xx_timeout *
-max63xx_select_timeout(struct max63xx_timeout *table, int value)
+static const struct max63xx_timeout *
+max63xx_select_timeout(const struct max63xx_timeout *table, int value)
 {
        while (table->twd) {
                if (value <= table->twd) {
@@ -202,14 +203,17 @@ static int max63xx_wdt_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
        struct max63xx_wdt *wdt;
-       struct max63xx_timeout *table;
+       const struct max63xx_timeout *table;
        int err;
 
        wdt = devm_kzalloc(dev, sizeof(*wdt), GFP_KERNEL);
        if (!wdt)
                return -ENOMEM;
 
-       table = (struct max63xx_timeout *)pdev->id_entry->driver_data;
+       /* Attempt to use fwnode first */
+       table = device_get_match_data(dev);
+       if (!table)
+               table = (struct max63xx_timeout *)pdev->id_entry->driver_data;
 
        if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
                heartbeat = DEFAULT_HEARTBEAT;
@@ -255,11 +259,23 @@ static const struct platform_device_id max63xx_id_table[] = {
 };
 MODULE_DEVICE_TABLE(platform, max63xx_id_table);
 
+static const struct of_device_id max63xx_dt_id_table[] = {
+       { .compatible = "maxim,max6369", .data = max6369_table, },
+       { .compatible = "maxim,max6370", .data = max6369_table, },
+       { .compatible = "maxim,max6371", .data = max6371_table, },
+       { .compatible = "maxim,max6372", .data = max6371_table, },
+       { .compatible = "maxim,max6373", .data = max6373_table, },
+       { .compatible = "maxim,max6374", .data = max6373_table, },
+       { }
+};
+MODULE_DEVICE_TABLE(of, max63xx_dt_id_table);
+
 static struct platform_driver max63xx_wdt_driver = {
        .probe          = max63xx_wdt_probe,
        .id_table       = max63xx_id_table,
        .driver         = {
                .name   = "max63xx_wdt",
+               .of_match_table = max63xx_dt_id_table,
        },
 };