[openwrt/staging/zorun.git] /

From f0d9d0f4b44ae5503ea368e7f066b20f12ca1d37 Mon Sep 17 00:00:00 2001
From: Matthew McClintock <mmcclint@codeaurora.org>
Date: Wed, 29 Jun 2016 10:50:01 -0700
Subject: watchdog: qcom: add option for standalone watchdog not in timer block

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.

The existing "kpss-standalone" compatible string doesn't
make it entirely clear exactly what the device is so
rename to "kpss-wdt" to reflect watchdog timer
functionality. Also update ipq4019 DTS with an SoC
specific compatible.

Signed-off-by: Matthew McClintock <mmcclint@codeaurora.org>
Signed-off-by: Thomas Pedersen <twp@codeaurora.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
---
 .../devicetree/bindings/watchdog/qcom-wdt.txt      |  2 +
 arch/arm/boot/dts/qcom-ipq4019.dtsi                |  2 +-
 drivers/watchdog/qcom-wdt.c                        | 64 ++++++++++++++++------
 3 files changed, 51 insertions(+), 17 deletions(-)

--- a/drivers/watchdog/qcom-wdt.c
+++ b/drivers/watchdog/qcom-wdt.c
@@ -18,19 +18,42 @@
 #include <linux/of.h>
 #include <linux/platform_device.h>
 #include <linux/watchdog.h>
+#include <linux/of_device.h>
 
-#define WDT_RST                0x38
-#define WDT_EN         0x40
-#define WDT_STS                0x44
-#define WDT_BITE_TIME  0x5C
+enum wdt_reg {
+       WDT_RST,
+       WDT_EN,
+       WDT_STS,
+       WDT_BITE_TIME,
+};
+
+static const u32 reg_offset_data_apcs_tmr[] = {
+       [WDT_RST] = 0x38,
+       [WDT_EN] = 0x40,
+       [WDT_STS] = 0x44,
+       [WDT_BITE_TIME] = 0x5C,
+};
+
+static const u32 reg_offset_data_kpss[] = {
+       [WDT_RST] = 0x4,
+       [WDT_EN] = 0x8,
+       [WDT_STS] = 0xC,
+       [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)
 {
@@ -41,10 +64,10 @@ static int qcom_wdt_start(struct watchdo
 {
        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;
 }
 
@@ -52,7 +75,7 @@ static int qcom_wdt_stop(struct watchdog
 {
        struct qcom_wdt *wdt = to_qcom_wdt(wdd);
 
-       writel(0, wdt->base + WDT_EN);
+       writel(0, wdt_addr(wdt, WDT_EN));
        return 0;
 }
 
@@ -60,7 +83,7 @@ static int qcom_wdt_ping(struct watchdog
 {
        struct qcom_wdt *wdt = to_qcom_wdt(wdd);
 
-       writel(1, wdt->base + WDT_RST);
+       writel(1, wdt_addr(wdt, WDT_RST));
        return 0;
 }
 
@@ -83,10 +106,10 @@ static int qcom_wdt_restart(struct watch
         */
        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.
@@ -119,9 +142,16 @@ static int qcom_wdt_probe(struct platfor
        struct qcom_wdt *wdt;
        struct resource *res;
        struct device_node *np = pdev->dev.of_node;
+       const u32 *regs;
        u32 percpu_offset;
        int ret;
 
+       regs = of_device_get_match_data(&pdev->dev);
+       if (!regs) {
+               dev_err(&pdev->dev, "Unsupported QCOM WDT module\n");
+               return -ENODEV;
+       }
+
        wdt = devm_kzalloc(&pdev->dev, sizeof(*wdt), GFP_KERNEL);
        if (!wdt)
                return -ENOMEM;
@@ -172,6 +202,7 @@ static int qcom_wdt_probe(struct platfor
        wdt->wdd.min_timeout = 1;
        wdt->wdd.max_timeout = 0x10000000U / wdt->rate;
        wdt->wdd.parent = &pdev->dev;
+       wdt->layout = regs;
 
        if (readl(wdt->base + WDT_STS) & 1)
                wdt->wdd.bootstatus = WDIOF_CARDRESET;
@@ -208,8 +239,9 @@ static int qcom_wdt_remove(struct platfo
 }
 
 static const struct of_device_id qcom_wdt_of_table[] = {
-       { .compatible = "qcom,kpss-timer" },
-       { .compatible = "qcom,scss-timer" },
+       { .compatible = "qcom,kpss-timer", .data = reg_offset_data_apcs_tmr },
+       { .compatible = "qcom,scss-timer", .data = reg_offset_data_apcs_tmr },
+       { .compatible = "qcom,kpss-wdt", .data = reg_offset_data_kpss },
        { },
 };
 MODULE_DEVICE_TABLE(of, qcom_wdt_of_table);