diff options
Diffstat (limited to 'drivers/watchdog/jz4740_wdt.c')
| -rw-r--r-- | drivers/watchdog/jz4740_wdt.c | 108 |
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); |