[PATCH 07/17] watchdog: qcom: add option for standalone watchdog not in timer block

From: Matthew McClintock
Date: Wed Mar 23 2016 - 18:06:13 EST


Commit 0dfd582e026a ("watchdog: qcom: use timer devicetree binding") moved
to use the watchdog as a subset timer register block. Some devices have the
watchdog completely standalone with slightly different register offsets as
well so let's account for the differences here.

Signed-off-by: Matthew McClintock <mmcclint@xxxxxxxxxxxxxx>
---
drivers/watchdog/qcom-wdt.c | 69 ++++++++++++++++++++++++++++++++-------------
1 file changed, 49 insertions(+), 20 deletions(-)

diff --git a/drivers/watchdog/qcom-wdt.c b/drivers/watchdog/qcom-wdt.c
index 20563cc..e46f18d 100644
--- a/drivers/watchdog/qcom-wdt.c
+++ b/drivers/watchdog/qcom-wdt.c
@@ -19,17 +19,37 @@
#include <linux/platform_device.h>
#include <linux/watchdog.h>

-#define WDT_RST 0x38
-#define WDT_EN 0x40
-#define WDT_BITE_TIME 0x5C
+enum wdt_reg {
+ WDT_RST,
+ WDT_EN,
+ WDT_BITE_TIME,
+};
+
+static const u32 reg_offset_data_apcs_tmr[] = {
+ [WDT_RST] = 0x38,
+ [WDT_EN] = 0x40,
+ [WDT_BITE_TIME] = 0x5C,
+};
+
+static const u32 reg_offset_data_kpss[] = {
+ [WDT_RST] = 0x4,
+ [WDT_EN] = 0x8,
+ [WDT_BITE_TIME] = 0x14,
+};

struct qcom_wdt {
struct watchdog_device wdd;
struct clk *clk;
unsigned long rate;
void __iomem *base;
+ const u32 *layout;
};

+static void __iomem *wdt_addr(struct qcom_wdt *wdt, enum wdt_reg reg)
+{
+ return wdt->base + wdt->layout[reg];
+}
+
static inline
struct qcom_wdt *to_qcom_wdt(struct watchdog_device *wdd)
{
@@ -40,10 +60,10 @@ static int qcom_wdt_start(struct watchdog_device *wdd)
{
struct qcom_wdt *wdt = to_qcom_wdt(wdd);

- writel(0, wdt->base + WDT_EN);
- writel(1, wdt->base + WDT_RST);
- writel(wdd->timeout * wdt->rate, wdt->base + WDT_BITE_TIME);
- writel(1, wdt->base + WDT_EN);
+ writel(0, wdt_addr(wdt, WDT_EN));
+ writel(1, wdt_addr(wdt, WDT_RST));
+ writel(wdd->timeout * wdt->rate, wdt_addr(wdt, WDT_BITE_TIME));
+ writel(1, wdt_addr(wdt, WDT_EN));
return 0;
}

@@ -51,7 +71,7 @@ static int qcom_wdt_stop(struct watchdog_device *wdd)
{
struct qcom_wdt *wdt = to_qcom_wdt(wdd);

- writel(0, wdt->base + WDT_EN);
+ writel(0, wdt_addr(wdt, WDT_EN));
return 0;
}

@@ -59,7 +79,7 @@ static int qcom_wdt_ping(struct watchdog_device *wdd)
{
struct qcom_wdt *wdt = to_qcom_wdt(wdd);

- writel(1, wdt->base + WDT_RST);
+ writel(1, wdt_addr(wdt, WDT_RST));
return 0;
}

@@ -82,10 +102,10 @@ static int qcom_wdt_restart(struct watchdog_device *wdd, unsigned long action,
*/
timeout = 128 * wdt->rate / 1000;

- writel(0, wdt->base + WDT_EN);
- writel(1, wdt->base + WDT_RST);
- writel(timeout, wdt->base + WDT_BITE_TIME);
- writel(1, wdt->base + WDT_EN);
+ writel(0, wdt_addr(wdt, WDT_EN));
+ writel(1, wdt_addr(wdt, WDT_RST));
+ writel(timeout, wdt_addr(wdt, WDT_BITE_TIME));
+ writel(1, wdt_addr(wdt, WDT_EN));

/*
* Actually make sure the above sequence hits hardware before sleeping.
@@ -112,14 +132,29 @@ static const struct watchdog_info qcom_wdt_info = {
.identity = KBUILD_MODNAME,
};

+static const struct of_device_id qcom_wdt_of_table[] = {
+ { .compatible = "qcom,kpss-timer", .data = reg_offset_data_apcs_tmr },
+ { .compatible = "qcom,scss-timer", .data = reg_offset_data_apcs_tmr },
+ { .compatible = "qcom,kpss-standalone", .data = &reg_offset_data_kpss},
+ { },
+};
+MODULE_DEVICE_TABLE(of, qcom_wdt_of_table);
+
static int qcom_wdt_probe(struct platform_device *pdev)
{
struct qcom_wdt *wdt;
struct resource *res;
struct device_node *np = pdev->dev.of_node;
+ const struct of_device_id *match;
u32 percpu_offset;
int ret;

+ match = of_match_node(qcom_wdt_of_table, np);
+ if (!match) {
+ dev_err(&pdev->dev, "Unsupported QCOM WDT module\n");
+ return -ENODEV;
+ }
+
wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
if (!wdt)
return -ENOMEM;
@@ -170,6 +205,7 @@ static int qcom_wdt_probe(struct platform_device *pdev)
wdt->wdd.min_timeout = 1;
wdt->wdd.max_timeout = 0x10000000U / wdt->rate;
wdt->wdd.parent = &pdev->dev;
+ wdt->layout = match->data;

/*
* If 'timeout-sec' unspecified in devicetree, assume a 30 second
@@ -202,13 +238,6 @@ static int qcom_wdt_remove(struct platform_device *pdev)
return 0;
}

-static const struct of_device_id qcom_wdt_of_table[] = {
- { .compatible = "qcom,kpss-timer" },
- { .compatible = "qcom,scss-timer" },
- { },
-};
-MODULE_DEVICE_TABLE(of, qcom_wdt_of_table);
-
static struct platform_driver qcom_watchdog_driver = {
.probe = qcom_wdt_probe,
.remove = qcom_wdt_remove,
--
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