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path: root/drivers/watchdog/jz4740_wdt.c
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Diffstat (limited to 'drivers/watchdog/jz4740_wdt.c')
-rw-r--r--drivers/watchdog/jz4740_wdt.c108
1 files changed, 49 insertions, 59 deletions
diff --git a/drivers/watchdog/jz4740_wdt.c b/drivers/watchdog/jz4740_wdt.c
index c6052ae54f32..bdf9564efa29 100644
--- a/drivers/watchdog/jz4740_wdt.c
+++ b/drivers/watchdog/jz4740_wdt.c
@@ -5,6 +5,7 @@
*/
#include <linux/mfd/ingenic-tcu.h>
+#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
@@ -17,19 +18,7 @@
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/of.h>
-
-#include <asm/mach-jz4740/timer.h>
-
-#define JZ_WDT_CLOCK_PCLK 0x1
-#define JZ_WDT_CLOCK_RTC 0x2
-#define JZ_WDT_CLOCK_EXT 0x4
-
-#define JZ_WDT_CLOCK_DIV_1 (0 << TCU_TCSR_PRESCALE_LSB)
-#define JZ_WDT_CLOCK_DIV_4 (1 << TCU_TCSR_PRESCALE_LSB)
-#define JZ_WDT_CLOCK_DIV_16 (2 << TCU_TCSR_PRESCALE_LSB)
-#define JZ_WDT_CLOCK_DIV_64 (3 << TCU_TCSR_PRESCALE_LSB)
-#define JZ_WDT_CLOCK_DIV_256 (4 << TCU_TCSR_PRESCALE_LSB)
-#define JZ_WDT_CLOCK_DIV_1024 (5 << TCU_TCSR_PRESCALE_LSB)
+#include <linux/regmap.h>
#define DEFAULT_HEARTBEAT 5
#define MAX_HEARTBEAT 2048
@@ -49,15 +38,17 @@ MODULE_PARM_DESC(heartbeat,
struct jz4740_wdt_drvdata {
struct watchdog_device wdt;
- void __iomem *base;
- struct clk *rtc_clk;
+ struct regmap *map;
+ struct clk *clk;
+ unsigned long clk_rate;
};
static int jz4740_wdt_ping(struct watchdog_device *wdt_dev)
{
struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
- writew(0x0, drvdata->base + TCU_REG_WDT_TCNT);
+ regmap_write(drvdata->map, TCU_REG_WDT_TCNT, 0);
+
return 0;
}
@@ -65,35 +56,17 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
unsigned int new_timeout)
{
struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
- unsigned int rtc_clk_rate;
- unsigned int timeout_value;
- unsigned short clock_div = JZ_WDT_CLOCK_DIV_1;
- u8 tcer;
-
- rtc_clk_rate = clk_get_rate(drvdata->rtc_clk);
-
- timeout_value = rtc_clk_rate * new_timeout;
- while (timeout_value > 0xffff) {
- if (clock_div == JZ_WDT_CLOCK_DIV_1024) {
- /* Requested timeout too high;
- * use highest possible value. */
- timeout_value = 0xffff;
- break;
- }
- timeout_value >>= 2;
- clock_div += (1 << TCU_TCSR_PRESCALE_LSB);
- }
+ u16 timeout_value = (u16)(drvdata->clk_rate * new_timeout);
+ unsigned int tcer;
- tcer = readb(drvdata->base + TCU_REG_WDT_TCER);
- writeb(0x0, drvdata->base + TCU_REG_WDT_TCER);
- writew(clock_div, drvdata->base + TCU_REG_WDT_TCSR);
+ regmap_read(drvdata->map, TCU_REG_WDT_TCER, &tcer);
+ regmap_write(drvdata->map, TCU_REG_WDT_TCER, 0);
- writew((u16)timeout_value, drvdata->base + TCU_REG_WDT_TDR);
- writew(0x0, drvdata->base + TCU_REG_WDT_TCNT);
- writew(clock_div | JZ_WDT_CLOCK_RTC, drvdata->base + TCU_REG_WDT_TCSR);
+ regmap_write(drvdata->map, TCU_REG_WDT_TDR, timeout_value);
+ regmap_write(drvdata->map, TCU_REG_WDT_TCNT, 0);
if (tcer & TCU_WDT_TCER_TCEN)
- writeb(TCU_WDT_TCER_TCEN, drvdata->base + TCU_REG_WDT_TCER);
+ regmap_write(drvdata->map, TCU_REG_WDT_TCER, TCU_WDT_TCER_TCEN);
wdt_dev->timeout = new_timeout;
return 0;
@@ -102,16 +75,20 @@ static int jz4740_wdt_set_timeout(struct watchdog_device *wdt_dev,
static int jz4740_wdt_start(struct watchdog_device *wdt_dev)
{
struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
- u8 tcer;
+ unsigned int tcer;
+ int ret;
- tcer = readb(drvdata->base + TCU_REG_WDT_TCER);
+ ret = clk_prepare_enable(drvdata->clk);
+ if (ret)
+ return ret;
+
+ regmap_read(drvdata->map, TCU_REG_WDT_TCER, &tcer);
- jz4740_timer_enable_watchdog();
jz4740_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
/* Start watchdog if it wasn't started already */
if (!(tcer & TCU_WDT_TCER_TCEN))
- writeb(TCU_WDT_TCER_TCEN, drvdata->base + TCU_REG_WDT_TCER);
+ regmap_write(drvdata->map, TCU_REG_WDT_TCER, TCU_WDT_TCER_TCEN);
return 0;
}
@@ -120,8 +97,8 @@ static int jz4740_wdt_stop(struct watchdog_device *wdt_dev)
{
struct jz4740_wdt_drvdata *drvdata = watchdog_get_drvdata(wdt_dev);
- writeb(0x0, drvdata->base + TCU_REG_WDT_TCER);
- jz4740_timer_disable_watchdog();
+ regmap_write(drvdata->map, TCU_REG_WDT_TCER, 0);
+ clk_disable_unprepare(drvdata->clk);
return 0;
}
@@ -162,33 +139,46 @@ static int jz4740_wdt_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct jz4740_wdt_drvdata *drvdata;
struct watchdog_device *jz4740_wdt;
+ long rate;
+ int ret;
drvdata = devm_kzalloc(dev, sizeof(struct jz4740_wdt_drvdata),
GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
- if (heartbeat < 1 || heartbeat > MAX_HEARTBEAT)
- heartbeat = DEFAULT_HEARTBEAT;
+ drvdata->clk = devm_clk_get(&pdev->dev, "wdt");
+ if (IS_ERR(drvdata->clk)) {
+ dev_err(&pdev->dev, "cannot find WDT clock\n");
+ return PTR_ERR(drvdata->clk);
+ }
+
+ /* Set smallest clock possible */
+ rate = clk_round_rate(drvdata->clk, 1);
+ if (rate < 0)
+ return rate;
+ ret = clk_set_rate(drvdata->clk, rate);
+ if (ret)
+ return ret;
+
+ drvdata->clk_rate = rate;
jz4740_wdt = &drvdata->wdt;
jz4740_wdt->info = &jz4740_wdt_info;
jz4740_wdt->ops = &jz4740_wdt_ops;
- jz4740_wdt->timeout = heartbeat;
jz4740_wdt->min_timeout = 1;
- jz4740_wdt->max_timeout = MAX_HEARTBEAT;
+ jz4740_wdt->max_timeout = 0xffff / rate;
+ jz4740_wdt->timeout = clamp(heartbeat,
+ jz4740_wdt->min_timeout,
+ jz4740_wdt->max_timeout);
jz4740_wdt->parent = dev;
watchdog_set_nowayout(jz4740_wdt, nowayout);
watchdog_set_drvdata(jz4740_wdt, drvdata);
- drvdata->base = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(drvdata->base))
- return PTR_ERR(drvdata->base);
-
- drvdata->rtc_clk = devm_clk_get(dev, "rtc");
- if (IS_ERR(drvdata->rtc_clk)) {
- dev_err(dev, "cannot find RTC clock\n");
- return PTR_ERR(drvdata->rtc_clk);
+ drvdata->map = device_node_to_regmap(dev->parent->of_node);
+ if (!drvdata->map) {
+ dev_err(dev, "regmap not found\n");
+ return -EINVAL;
}
return devm_watchdog_register_device(dev, &drvdata->wdt);