[PATCH v2 1/3] watchdog: sama5d4: Cleanup init

From: Alexandre Belloni
Date: Thu Feb 16 2017 - 14:31:15 EST


.config is used to cache a part of WDT_MR at probe time and is not used
afterwards. Also functions are used while they always return 0. Simplify
the flow by having everything in .probe().

Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxxxxxxxxx>
---
Changes in v2:
- completely get rid of .config instead of caching it
- merge init functions in probe()

drivers/watchdog/sama5d4_wdt.c | 92 ++++++++++++++++--------------------------
1 file changed, 34 insertions(+), 58 deletions(-)

diff --git a/drivers/watchdog/sama5d4_wdt.c b/drivers/watchdog/sama5d4_wdt.c
index a49634cdc1cc..2c6f5a70ae67 100644
--- a/drivers/watchdog/sama5d4_wdt.c
+++ b/drivers/watchdog/sama5d4_wdt.c
@@ -28,7 +28,6 @@
struct sama5d4_wdt {
struct watchdog_device wdd;
void __iomem *reg_base;
- u32 config;
};

static int wdt_timeout = WDT_DEFAULT_TIMEOUT;
@@ -128,57 +127,15 @@ static irqreturn_t sama5d4_wdt_irq_handler(int irq, void *dev_id)
return IRQ_HANDLED;
}

-static int of_sama5d4_wdt_init(struct device_node *np, struct sama5d4_wdt *wdt)
-{
- const char *tmp;
-
- wdt->config = AT91_WDT_WDDIS;
-
- if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
- !strcmp(tmp, "software"))
- wdt->config |= AT91_WDT_WDFIEN;
- else
- wdt->config |= AT91_WDT_WDRSTEN;
-
- if (of_property_read_bool(np, "atmel,idle-halt"))
- wdt->config |= AT91_WDT_WDIDLEHLT;
-
- if (of_property_read_bool(np, "atmel,dbg-halt"))
- wdt->config |= AT91_WDT_WDDBGHLT;
-
- return 0;
-}
-
-static int sama5d4_wdt_init(struct sama5d4_wdt *wdt)
-{
- struct watchdog_device *wdd = &wdt->wdd;
- u32 value = WDT_SEC2TICKS(wdd->timeout);
- u32 reg;
-
- /*
- * Because the fields WDV and WDD must not be modified when the WDDIS
- * bit is set, so clear the WDDIS bit before writing the WDT_MR.
- */
- reg = wdt_read(wdt, AT91_WDT_MR);
- 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_write(wdt, AT91_WDT_MR, reg);
-
- return 0;
-}
-
static int sama5d4_wdt_probe(struct platform_device *pdev)
{
struct watchdog_device *wdd;
struct sama5d4_wdt *wdt;
struct resource *res;
void __iomem *regs;
- u32 irq = 0;
+ struct device_node *np = pdev->dev.of_node;
+ const char *tmp;
+ u32 mr, reg, irq = 0;
int ret;

wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
@@ -201,17 +158,26 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)

wdt->reg_base = regs;

- if (pdev->dev.of_node) {
- irq = irq_of_parse_and_map(pdev->dev.of_node, 0);
- if (!irq)
- dev_warn(&pdev->dev, "failed to get IRQ from DT\n");
+ irq = irq_of_parse_and_map(np, 0);
+ if (!irq)
+ dev_warn(&pdev->dev, "failed to get IRQ from DT\n");

- ret = of_sama5d4_wdt_init(pdev->dev.of_node, wdt);
- if (ret)
- return ret;
- }

- if ((wdt->config & AT91_WDT_WDFIEN) && irq) {
+ mr = AT91_WDT_WDDIS;
+
+ if (!of_property_read_string(np, "atmel,watchdog-type", &tmp) &&
+ !strcmp(tmp, "software"))
+ mr |= AT91_WDT_WDFIEN;
+ else
+ mr |= AT91_WDT_WDRSTEN;
+
+ if (of_property_read_bool(np, "atmel,idle-halt"))
+ mr |= AT91_WDT_WDIDLEHLT;
+
+ if (of_property_read_bool(np, "atmel,dbg-halt"))
+ mr |= AT91_WDT_WDDBGHLT;
+
+ if ((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);
@@ -228,9 +194,19 @@ static int sama5d4_wdt_probe(struct platform_device *pdev)
return ret;
}

- ret = sama5d4_wdt_init(wdt);
- if (ret)
- return ret;
+ /*
+ * WDV and WDD must not be modified when the WDDIS bit is set, so clear
+ * the WDDIS bit before writing the WDT_MR.
+ */
+ reg = wdt_read(wdt, AT91_WDT_MR);
+ reg &= ~AT91_WDT_WDDIS;
+ wdt_write(wdt, AT91_WDT_MR, reg);
+
+ reg = mr;
+ reg |= AT91_WDT_SET_WDD(WDT_SEC2TICKS(wdd->timeout));
+ reg |= AT91_WDT_SET_WDV(WDT_SEC2TICKS(wdd->timeout));
+
+ wdt_write(wdt, AT91_WDT_MR, reg);

watchdog_set_nowayout(wdd, nowayout);

--
2.11.0