On 07/04/2018 08:22 PM, Srinath Mannam wrote:
When using ACPI node, binding clock devices are
not available as device tree, So clock-frequency
property given in _DSD object of ACPI device is
used to calculate Watchdog rate.
Signed-off-by: Srinath Mannam <[email protected]>
---
drivers/watchdog/sp805_wdt.c | 29 ++++++++++++++++++++++++-----
1 file changed, 24 insertions(+), 5 deletions(-)
diff --git a/drivers/watchdog/sp805_wdt.c b/drivers/watchdog/sp805_wdt.c
index 9849db0..d830dbc 100644
--- a/drivers/watchdog/sp805_wdt.c
+++ b/drivers/watchdog/sp805_wdt.c
@@ -22,6 +22,7 @@
#include <linux/math64.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
+#include <linux/of.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
@@ -65,6 +66,7 @@ struct sp805_wdt {
spinlock_t lock;
void __iomem *base;
struct clk *clk;
+ u64 rate;
struct amba_device *adev;
unsigned int load_val;
};
@@ -80,7 +82,10 @@ static int wdt_setload(struct watchdog_device *wdd, unsigned
int timeout)
struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
u64 load, rate;
- rate = clk_get_rate(wdt->clk);
+ if (wdt->rate)
+ rate = wdt->rate;
+ else
+ rate = clk_get_rate(wdt->clk);
No. Get the rate once during probe and store it in wdt->rate.
/*
* sp805 runs counter with given value twice, after the end of first
@@ -108,7 +113,10 @@ static unsigned int wdt_timeleft(struct watchdog_device
*wdd)
struct sp805_wdt *wdt = watchdog_get_drvdata(wdd);
u64 load, rate;
- rate = clk_get_rate(wdt->clk);
+ if (wdt->rate)
+ rate = wdt->rate;
+ else
+ rate = clk_get_rate(wdt->clk);
Same here.
spin_lock(&wdt->lock);
load = readl_relaxed(wdt->base + WDTVALUE);
@@ -230,11 +238,22 @@ sp805_wdt_probe(struct amba_device *adev, const struct
amba_id *id)
wdt->clk = devm_clk_get(&adev->dev, NULL);
if (IS_ERR(wdt->clk)) {
- dev_warn(&adev->dev, "Clock not found\n");
- ret = PTR_ERR(wdt->clk);
- goto err;
+ dev_warn(&adev->dev, "Clock device not found\n");
"Clock _device_" ? Why this change ? And why retain that warning
unconditionally ?
+ wdt->clk = NULL;
+ /*
+ * When Driver probe with ACPI device, clock devices
+ * are not available, so watchdog rate get from
+ * clock-frequency property given in _DSD object.
+ */
+ device_property_read_u64(&adev->dev, "clock-frequency",
+ &wdt->rate);
+ if (!wdt->rate) {
+ ret = -ENODEV;
This unconditionally overrides the original error.
+ goto err;
+ }
}
+
No whitespace changes, please.
Does that mean that ACPI doesn't support the clock subsystem and that each
driver
supporting ACPI must do this ? That would be messy. Also, the above does not
check
if the device was probed through ACPI. It just tries to find an undocumented
"clock-frequency" property which is quite different and would apply to
(probably mis-configured) devicetree files as well.
Either case, I would rather have this addressed through the clock subsystem.
Otherwise, someone with subject knowledge will have to confirm that this is the
appropriate solution. If so, the new property will have to be documented as an
alternative to clock specifiers and accepted by devicetree maintainers.
Guenter
wdt->adev = adev;
wdt->wdd.info = &wdt_info;
wdt->wdd.ops = &wdt_ops;
