[PATCH v3 2/2] drivers/watchdog: ASPEED reference dev tree properties for config

From: Christopher Bostic
Date: Wed Jun 28 2017 - 20:29:02 EST


Reference the system device tree when configuring the watchdog
engines. If optional property 'aspeed,no-sys-reset' is specified
then override the default config and do not set sys reset mode.
If optional property 'aspeed,no-soc-reset' is specified then
override the default and do not set soc reset mode.

Signed-off-by: Christopher Bostic <cbostic@xxxxxxxxxxxxxxxxxx>
---
v3 - Invert the logic for system reset dev tree property to
preserve backwards compatibility. If not specified the
default is to configure for system reset
- Add check for 'aspeed,no-soc-reset' property and only if
not present is SOC reset to be configured. This preserves
backwards compatibility.
v2 - Change of_get_property() to of_property_read_bool()
- Remove redundant check for NULL struct device_node pointer
- Optional property names now start with prefix 'aspeed,'
---
drivers/watchdog/aspeed_wdt.c | 20 +++++++++++++++-----
1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/drivers/watchdog/aspeed_wdt.c b/drivers/watchdog/aspeed_wdt.c
index 1c65258..ace74f8 100644
--- a/drivers/watchdog/aspeed_wdt.c
+++ b/drivers/watchdog/aspeed_wdt.c
@@ -140,6 +140,7 @@ static int aspeed_wdt_probe(struct platform_device *pdev)
{
struct aspeed_wdt *wdt;
struct resource *res;
+ struct device_node *np;
int ret;

wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
@@ -166,12 +167,21 @@ static int aspeed_wdt_probe(struct platform_device *pdev)

/*
* Control reset on a per-device basis to ensure the
- * host is not affected by a BMC reboot, so only reset
- * the SOC and not the full chip
+ * host is not affected by a BMC reboot
*/
- wdt->ctrl = WDT_CTRL_RESET_MODE_SOC |
- WDT_CTRL_1MHZ_CLK |
- WDT_CTRL_RESET_SYSTEM;
+ wdt->ctrl = WDT_CTRL_1MHZ_CLK;
+
+ np = pdev->dev.of_node;
+ if (!(of_property_read_bool(np, "aspeed,no-soc-reset")))
+ wdt->ctrl |= WDT_CTRL_RESET_MODE_SOC;
+
+ if (!(of_property_read_bool(np, "aspeed,no-sys-reset")))
+ wdt->ctrl |= WDT_CTRL_RESET_SYSTEM;
+
+ if (of_property_read_bool(np, "aspeed,external-signal"))
+ wdt->ctrl |= WDT_CTRL_WDT_EXT;
+
+ writel(wdt->ctrl, wdt->base + WDT_CTRL);

if (readl(wdt->base + WDT_CTRL) & WDT_CTRL_ENABLE) {
aspeed_wdt_start(&wdt->wdd);
--
1.8.2.2