diff options
Diffstat (limited to 'drivers/rtc/rtc-stmp3xxx.c')
| -rw-r--r-- | drivers/rtc/rtc-stmp3xxx.c | 177 |
1 files changed, 124 insertions, 53 deletions
diff --git a/drivers/rtc/rtc-stmp3xxx.c b/drivers/rtc/rtc-stmp3xxx.c index 10287865e33..ea96492357b 100644 --- a/drivers/rtc/rtc-stmp3xxx.c +++ b/drivers/rtc/rtc-stmp3xxx.c @@ -23,10 +23,13 @@ #include <linux/init.h> #include <linux/platform_device.h> #include <linux/interrupt.h> +#include <linux/delay.h> #include <linux/rtc.h> #include <linux/slab.h> - -#include <mach/common.h> +#include <linux/of_device.h> +#include <linux/of.h> +#include <linux/stmp_device.h> +#include <linux/stmp3xxx_rtc_wdt.h> #define STMP3XXX_RTC_CTRL 0x0 #define STMP3XXX_RTC_CTRL_SET 0x4 @@ -34,6 +37,7 @@ #define STMP3XXX_RTC_CTRL_ALARM_IRQ_EN 0x00000001 #define STMP3XXX_RTC_CTRL_ONEMSEC_IRQ_EN 0x00000002 #define STMP3XXX_RTC_CTRL_ALARM_IRQ 0x00000004 +#define STMP3XXX_RTC_CTRL_WATCHDOGEN 0x00000010 #define STMP3XXX_RTC_STAT 0x10 #define STMP3XXX_RTC_STAT_STALE_SHIFT 16 @@ -43,6 +47,8 @@ #define STMP3XXX_RTC_ALARM 0x40 +#define STMP3XXX_RTC_WATCHDOG 0x50 + #define STMP3XXX_RTC_PERSISTENT0 0x60 #define STMP3XXX_RTC_PERSISTENT0_SET 0x64 #define STMP3XXX_RTC_PERSISTENT0_CLR 0x68 @@ -50,30 +56,103 @@ #define STMP3XXX_RTC_PERSISTENT0_ALARM_EN 0x00000004 #define STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE 0x00000080 +#define STMP3XXX_RTC_PERSISTENT1 0x70 +/* missing bitmask in headers */ +#define STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER 0x80000000 + struct stmp3xxx_rtc_data { struct rtc_device *rtc; void __iomem *io; int irq_alarm; }; -static void stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data) +#if IS_ENABLED(CONFIG_STMP3XXX_RTC_WATCHDOG) +/** + * stmp3xxx_wdt_set_timeout - configure the watchdog inside the STMP3xxx RTC + * @dev: the parent device of the watchdog (= the RTC) + * @timeout: the desired value for the timeout register of the watchdog. + * 0 disables the watchdog + * + * The watchdog needs one register and two bits which are in the RTC domain. + * To handle the resource conflict, the RTC driver will create another + * platform_device for the watchdog driver as a child of the RTC device. + * The watchdog driver is passed the below accessor function via platform_data + * to configure the watchdog. Locking is not needed because accessing SET/CLR + * registers is atomic. + */ + +static void stmp3xxx_wdt_set_timeout(struct device *dev, u32 timeout) +{ + struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); + + if (timeout) { + writel(timeout, rtc_data->io + STMP3XXX_RTC_WATCHDOG); + writel(STMP3XXX_RTC_CTRL_WATCHDOGEN, + rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_SET); + writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER, + rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_SET); + } else { + writel(STMP3XXX_RTC_CTRL_WATCHDOGEN, + rtc_data->io + STMP3XXX_RTC_CTRL + STMP_OFFSET_REG_CLR); + writel(STMP3XXX_RTC_PERSISTENT1_FORCE_UPDATER, + rtc_data->io + STMP3XXX_RTC_PERSISTENT1 + STMP_OFFSET_REG_CLR); + } +} + +static struct stmp3xxx_wdt_pdata wdt_pdata = { + .wdt_set_timeout = stmp3xxx_wdt_set_timeout, +}; + +static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev) { + struct platform_device *wdt_pdev = + platform_device_alloc("stmp3xxx_rtc_wdt", rtc_pdev->id); + + if (wdt_pdev) { + wdt_pdev->dev.parent = &rtc_pdev->dev; + wdt_pdev->dev.platform_data = &wdt_pdata; + platform_device_add(wdt_pdev); + } +} +#else +static void stmp3xxx_wdt_register(struct platform_device *rtc_pdev) +{ +} +#endif /* CONFIG_STMP3XXX_RTC_WATCHDOG */ + +static int stmp3xxx_wait_time(struct stmp3xxx_rtc_data *rtc_data) +{ + int timeout = 5000; /* 3ms according to i.MX28 Ref Manual */ /* - * The datasheet doesn't say which way round the - * NEW_REGS/STALE_REGS bitfields go. In fact it's 0x1=P0, - * 0x2=P1, .., 0x20=P5, 0x40=ALARM, 0x80=SECONDS + * The i.MX28 Applications Processor Reference Manual, Rev. 1, 2010 + * states: + * | The order in which registers are updated is + * | Persistent 0, 1, 2, 3, 4, 5, Alarm, Seconds. + * | (This list is in bitfield order, from LSB to MSB, as they would + * | appear in the STALE_REGS and NEW_REGS bitfields of the HW_RTC_STAT + * | register. For example, the Seconds register corresponds to + * | STALE_REGS or NEW_REGS containing 0x80.) */ - while (readl(rtc_data->io + STMP3XXX_RTC_STAT) & - (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) - cpu_relax(); + do { + if (!(readl(rtc_data->io + STMP3XXX_RTC_STAT) & + (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT))) + return 0; + udelay(1); + } while (--timeout > 0); + return (readl(rtc_data->io + STMP3XXX_RTC_STAT) & + (0x80 << STMP3XXX_RTC_STAT_STALE_SHIFT)) ? -ETIME : 0; } /* Time read/write */ static int stmp3xxx_rtc_gettime(struct device *dev, struct rtc_time *rtc_tm) { + int ret; struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - stmp3xxx_wait_time(rtc_data); + ret = stmp3xxx_wait_time(rtc_data); + if (ret) + return ret; + rtc_time_to_tm(readl(rtc_data->io + STMP3XXX_RTC_SECONDS), rtc_tm); return 0; } @@ -83,8 +162,7 @@ static int stmp3xxx_rtc_set_mmss(struct device *dev, unsigned long t) struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); writel(t, rtc_data->io + STMP3XXX_RTC_SECONDS); - stmp3xxx_wait_time(rtc_data); - return 0; + return stmp3xxx_wait_time(rtc_data); } /* interrupt(s) handler */ @@ -162,11 +240,6 @@ static int stmp3xxx_rtc_remove(struct platform_device *pdev) writel(STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, rtc_data->io + STMP3XXX_RTC_CTRL_CLR); - free_irq(rtc_data->irq_alarm, &pdev->dev); - rtc_device_unregister(rtc_data->rtc); - platform_set_drvdata(pdev, NULL); - iounmap(rtc_data->io); - kfree(rtc_data); return 0; } @@ -177,22 +250,20 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) struct resource *r; int err; - rtc_data = kzalloc(sizeof *rtc_data, GFP_KERNEL); + rtc_data = devm_kzalloc(&pdev->dev, sizeof(*rtc_data), GFP_KERNEL); if (!rtc_data) return -ENOMEM; r = platform_get_resource(pdev, IORESOURCE_MEM, 0); if (!r) { dev_err(&pdev->dev, "failed to get resource\n"); - err = -ENXIO; - goto out_free; + return -ENXIO; } - rtc_data->io = ioremap(r->start, resource_size(r)); + rtc_data->io = devm_ioremap(&pdev->dev, r->start, resource_size(r)); if (!rtc_data->io) { dev_err(&pdev->dev, "ioremap failed\n"); - err = -EIO; - goto out_free; + return -EIO; } rtc_data->irq_alarm = platform_get_irq(pdev, 0); @@ -200,13 +271,17 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) if (!(readl(STMP3XXX_RTC_STAT + rtc_data->io) & STMP3XXX_RTC_STAT_RTC_PRESENT)) { dev_err(&pdev->dev, "no device onboard\n"); - err = -ENODEV; - goto out_remap; + return -ENODEV; } platform_set_drvdata(pdev, rtc_data); - mxs_reset_block(rtc_data->io); + err = stmp_reset_block(rtc_data->io); + if (err) { + dev_err(&pdev->dev, "stmp_reset_block failed: %d\n", err); + return err; + } + writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, @@ -216,63 +291,59 @@ static int stmp3xxx_rtc_probe(struct platform_device *pdev) STMP3XXX_RTC_CTRL_ALARM_IRQ_EN, rtc_data->io + STMP3XXX_RTC_CTRL_CLR); - rtc_data->rtc = rtc_device_register(pdev->name, &pdev->dev, + rtc_data->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &stmp3xxx_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc_data->rtc)) { - err = PTR_ERR(rtc_data->rtc); - goto out_remap; - } + if (IS_ERR(rtc_data->rtc)) + return PTR_ERR(rtc_data->rtc); - err = request_irq(rtc_data->irq_alarm, stmp3xxx_rtc_interrupt, 0, - "RTC alarm", &pdev->dev); + err = devm_request_irq(&pdev->dev, rtc_data->irq_alarm, + stmp3xxx_rtc_interrupt, 0, "RTC alarm", &pdev->dev); if (err) { dev_err(&pdev->dev, "Cannot claim IRQ%d\n", rtc_data->irq_alarm); - goto out_irq_alarm; + return err; } + stmp3xxx_wdt_register(pdev); return 0; - -out_irq_alarm: - rtc_device_unregister(rtc_data->rtc); -out_remap: - platform_set_drvdata(pdev, NULL); - iounmap(rtc_data->io); -out_free: - kfree(rtc_data); - return err; } -#ifdef CONFIG_PM -static int stmp3xxx_rtc_suspend(struct platform_device *dev, pm_message_t state) +#ifdef CONFIG_PM_SLEEP +static int stmp3xxx_rtc_suspend(struct device *dev) { return 0; } -static int stmp3xxx_rtc_resume(struct platform_device *dev) +static int stmp3xxx_rtc_resume(struct device *dev) { - struct stmp3xxx_rtc_data *rtc_data = platform_get_drvdata(dev); + struct stmp3xxx_rtc_data *rtc_data = dev_get_drvdata(dev); - mxs_reset_block(rtc_data->io); + stmp_reset_block(rtc_data->io); writel(STMP3XXX_RTC_PERSISTENT0_ALARM_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE_EN | STMP3XXX_RTC_PERSISTENT0_ALARM_WAKE, rtc_data->io + STMP3XXX_RTC_PERSISTENT0_CLR); return 0; } -#else -#define stmp3xxx_rtc_suspend NULL -#define stmp3xxx_rtc_resume NULL #endif +static SIMPLE_DEV_PM_OPS(stmp3xxx_rtc_pm_ops, stmp3xxx_rtc_suspend, + stmp3xxx_rtc_resume); + +static const struct of_device_id rtc_dt_ids[] = { + { .compatible = "fsl,stmp3xxx-rtc", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, rtc_dt_ids); + static struct platform_driver stmp3xxx_rtcdrv = { .probe = stmp3xxx_rtc_probe, .remove = stmp3xxx_rtc_remove, - .suspend = stmp3xxx_rtc_suspend, - .resume = stmp3xxx_rtc_resume, .driver = { .name = "stmp3xxx-rtc", .owner = THIS_MODULE, + .pm = &stmp3xxx_rtc_pm_ops, + .of_match_table = rtc_dt_ids, }, }; |