[PATCH 1/2] watchdog: sama5d4: Cache MR instead of a partial config

[Alexandre Belloni]

.config is used to cache a part of WDT_MR at probe time and is not used
afterwards. Instead of doing that, actually cache MR and avoid reading it
every time it is modified.

Signed-off-by: Alexandre Belloni <alexandre.bell...@free-electrons.com>
---
 drivers/watchdog/sama5d4_wdt.c | 45 ++++++++++++++++++------------------------
 1 file changed, 19 insertions(+), 26 deletions(-)

diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
index a49634cdc1cc..6dd07bef515a 100644
--- a/drivers/watchdog/sama5d4_wdt.c
+++ b/drivers/watchdog/sama5d4_wdt.c
@@ -28,7 +28,7 @@
 struct sama5d4_wdt {
        struct watchdog_device  wdd;
        void __iomem            *reg_base;
-       u32     config;
+       u32                     mr;
 };
 
 static int wdt_timeout = WDT_DEFAULT_TIMEOUT;
@@ -53,11 +53,9 @@ MODULE_PARM_DESC(nowayout,
 static int sama5d4_wdt_start(struct watchdog_device *wdd)
 {
        struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
-       u32 reg;
 
-       reg = wdt_read(wdt, AT91_WDT_MR);
-       reg &= ~AT91_WDT_WDDIS;
-       wdt_write(wdt, AT91_WDT_MR, reg);
+       wdt->mr &= ~AT91_WDT_WDDIS;
+       wdt_write(wdt, AT91_WDT_MR, wdt->mr);
 
        return 0;
 }
@@ -65,11 +63,9 @@ static int sama5d4_wdt_start(struct watchdog_device *wdd)
 static int sama5d4_wdt_stop(struct watchdog_device *wdd)
 {
        struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
-       u32 reg;
 
-       reg = wdt_read(wdt, AT91_WDT_MR);
-       reg |= AT91_WDT_WDDIS;
-       wdt_write(wdt, AT91_WDT_MR, reg);
+       wdt->mr |= AT91_WDT_WDDIS;
+       wdt_write(wdt, AT91_WDT_MR, wdt->mr);
 
        return 0;
 }
@@ -88,14 +84,12 @@ static int sama5d4_wdt_set_timeout(struct watchdog_device 
*wdd,
 {
        struct sama5d4_wdt *wdt = watchdog_get_drvdata(wdd);
        u32 value = WDT_SEC2TICKS(timeout);
-       u32 reg;
 
-       reg = wdt_read(wdt, AT91_WDT_MR);
-       reg &= ~AT91_WDT_WDV;
-       reg &= ~AT91_WDT_WDD;
-       reg |= AT91_WDT_SET_WDV(value);
-       reg |= AT91_WDT_SET_WDD(value);
-       wdt_write(wdt, AT91_WDT_MR, reg);
+       wdt->mr &= ~AT91_WDT_WDV;
+       wdt->mr &= ~AT91_WDT_WDD;
+       wdt->mr |= AT91_WDT_SET_WDV(value);
+       wdt->mr |= AT91_WDT_SET_WDD(value);
+       wdt_write(wdt, AT91_WDT_MR, wdt->mr);
 
        wdd->timeout = timeout;
 
@@ -132,19 +126,19 @@ static int of_sama5d4_wdt_init(struct device_node *np, 
struct sama5d4_wdt *wdt)
 {
        const char *tmp;
 
-       wdt->config = AT91_WDT_WDDIS;
+       wdt->mr = AT91_WDT_WDDIS;
 
        if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
            !strcmp(tmp, "software"))
-               wdt->config |= AT91_WDT_WDFIEN;
+               wdt->mr |= AT91_WDT_WDFIEN;
        else
-               wdt->config |= AT91_WDT_WDRSTEN;
+               wdt->mr |= AT91_WDT_WDRSTEN;
 
        if (of_property_read_bool(np, "atmel,idle-halt"))
-               wdt->config |= AT91_WDT_WDIDLEHLT;
+               wdt->mr |= AT91_WDT_WDIDLEHLT;
 
        if (of_property_read_bool(np, "atmel,dbg-halt"))
-               wdt->config |= AT91_WDT_WDDBGHLT;
+               wdt->mr |= AT91_WDT_WDDBGHLT;
 
        return 0;
 }
@@ -163,11 +157,10 @@ static int sama5d4_wdt_init(struct sama5d4_wdt *wdt)
        reg &= ~AT91_WDT_WDDIS;
        wdt_write(wdt, AT91_WDT_MR, reg);
 
-       reg = wdt->config;
-       reg |= AT91_WDT_SET_WDD(value);
-       reg |= AT91_WDT_SET_WDV(value);
+       wdt->mr |= AT91_WDT_SET_WDD(value);
+       wdt->mr |= AT91_WDT_SET_WDV(value);
 
-       wdt_write(wdt, AT91_WDT_MR, reg);
+       wdt_write(wdt, AT91_WDT_MR, wdt->mr);
 
        return 0;
 }
@@ -211,7 +204,7 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
                        return ret;
        }
 
-       if ((wdt->config & AT91_WDT_WDFIEN) && irq) {
+       if ((wdt->mr & AT91_WDT_WDFIEN) && irq) {
                ret = devm_request_irq(&pdev->dev, irq, sama5d4_wdt_irq_handler,
                                       IRQF_SHARED | IRQF_IRQPOLL |
                                       IRQF_NO_SUSPEND, pdev->name, pdev);
-- 
2.11.0