diff options
Diffstat (limited to 'drivers/rtc/rtc-at91sam9.c')
| -rw-r--r-- | drivers/rtc/rtc-at91sam9.c | 138 |
1 files changed, 109 insertions, 29 deletions
diff --git a/drivers/rtc/rtc-at91sam9.c b/drivers/rtc/rtc-at91sam9.c index 5963743..abac38a 100644 --- a/drivers/rtc/rtc-at91sam9.c +++ b/drivers/rtc/rtc-at91sam9.c @@ -21,10 +21,9 @@ #include <linux/slab.h> #include <linux/platform_data/atmel.h> #include <linux/io.h> - -#include <mach/at91_rtt.h> -#include <mach/cpu.h> -#include <mach/hardware.h> +#include <linux/mfd/syscon.h> +#include <linux/regmap.h> +#include <linux/clk.h> /* * This driver uses two configurable hardware resources that live in the @@ -47,6 +46,22 @@ * registers available, likewise usable for more than "RTC" support. */ +#define AT91_RTT_MR 0x00 /* Real-time Mode Register */ +#define AT91_RTT_RTPRES (0xffff << 0) /* Real-time Timer Prescaler Value */ +#define AT91_RTT_ALMIEN (1 << 16) /* Alarm Interrupt Enable */ +#define AT91_RTT_RTTINCIEN (1 << 17) /* Real Time Timer Increment Interrupt Enable */ +#define AT91_RTT_RTTRST (1 << 18) /* Real Time Timer Restart */ + +#define AT91_RTT_AR 0x04 /* Real-time Alarm Register */ +#define AT91_RTT_ALMV (0xffffffff) /* Alarm Value */ + +#define AT91_RTT_VR 0x08 /* Real-time Value Register */ +#define AT91_RTT_CRTV (0xffffffff) /* Current Real-time Value */ + +#define AT91_RTT_SR 0x0c /* Real-time Status Register */ +#define AT91_RTT_ALMS (1 << 0) /* Real-time Alarm Status */ +#define AT91_RTT_RTTINC (1 << 1) /* Real-time Timer Increment */ + /* * We store ALARM_DISABLED in ALMV to record that no alarm is set. * It's also the reset value for that field. @@ -58,19 +73,30 @@ struct sam9_rtc { void __iomem *rtt; struct rtc_device *rtcdev; u32 imr; - void __iomem *gpbr; + struct regmap *gpbr; + unsigned int gpbr_offset; int irq; + struct clk *sclk; }; #define rtt_readl(rtc, field) \ - __raw_readl((rtc)->rtt + AT91_RTT_ ## field) + readl((rtc)->rtt + AT91_RTT_ ## field) #define rtt_writel(rtc, field, val) \ - __raw_writel((val), (rtc)->rtt + AT91_RTT_ ## field) + writel((val), (rtc)->rtt + AT91_RTT_ ## field) + +static inline unsigned int gpbr_readl(struct sam9_rtc *rtc) +{ + unsigned int val; + + regmap_read(rtc->gpbr, rtc->gpbr_offset, &val); -#define gpbr_readl(rtc) \ - __raw_readl((rtc)->gpbr) -#define gpbr_writel(rtc, val) \ - __raw_writel((val), (rtc)->gpbr) + return val; +} + +static inline void gpbr_writel(struct sam9_rtc *rtc, unsigned int val) +{ + regmap_write(rtc->gpbr, rtc->gpbr_offset, val); +} /* * Read current time and date in RTC @@ -287,22 +313,22 @@ static const struct rtc_class_ops at91_rtc_ops = { .alarm_irq_enable = at91_rtc_alarm_irq_enable, }; +static struct regmap_config gpbr_regmap_config = { + .reg_bits = 32, + .val_bits = 32, + .reg_stride = 4, +}; + /* * Initialize and install RTC driver */ static int at91_rtc_probe(struct platform_device *pdev) { - struct resource *r, *r_gpbr; + struct resource *r; struct sam9_rtc *rtc; int ret, irq; u32 mr; - - r = platform_get_resource(pdev, IORESOURCE_MEM, 0); - r_gpbr = platform_get_resource(pdev, IORESOURCE_MEM, 1); - if (!r || !r_gpbr) { - dev_err(&pdev->dev, "need 2 ressources\n"); - return -ENODEV; - } + unsigned int sclk_rate; irq = platform_get_irq(pdev, 0); if (irq < 0) { @@ -321,24 +347,66 @@ static int at91_rtc_probe(struct platform_device *pdev) device_init_wakeup(&pdev->dev, 1); platform_set_drvdata(pdev, rtc); - rtc->rtt = devm_ioremap(&pdev->dev, r->start, resource_size(r)); - if (!rtc->rtt) { - dev_err(&pdev->dev, "failed to map registers, aborting.\n"); - return -ENOMEM; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + rtc->rtt = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(rtc->rtt)) + return PTR_ERR(rtc->rtt); + + if (!pdev->dev.of_node) { + /* + * TODO: Remove this code chunk when removing non DT board + * support. Remember to remove the gpbr_regmap_config + * variable too. + */ + void __iomem *gpbr; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 1); + gpbr = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(gpbr)) + return PTR_ERR(gpbr); + + rtc->gpbr = regmap_init_mmio(NULL, gpbr, + &gpbr_regmap_config); + } else { + struct of_phandle_args args; + + ret = of_parse_phandle_with_fixed_args(pdev->dev.of_node, + "atmel,rtt-rtc-time-reg", 1, 0, + &args); + if (ret) + return ret; + + rtc->gpbr = syscon_node_to_regmap(args.np); + rtc->gpbr_offset = args.args[0]; } - rtc->gpbr = devm_ioremap(&pdev->dev, r_gpbr->start, - resource_size(r_gpbr)); - if (!rtc->gpbr) { - dev_err(&pdev->dev, "failed to map gpbr registers, aborting.\n"); + if (IS_ERR(rtc->gpbr)) { + dev_err(&pdev->dev, "failed to retrieve gpbr regmap, aborting.\n"); return -ENOMEM; } + rtc->sclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(rtc->sclk)) + return PTR_ERR(rtc->sclk); + + sclk_rate = clk_get_rate(rtc->sclk); + if (!sclk_rate || sclk_rate > AT91_RTT_RTPRES) { + dev_err(&pdev->dev, "Invalid slow clock rate\n"); + return -EINVAL; + } + + ret = clk_prepare_enable(rtc->sclk); + if (ret) { + dev_err(&pdev->dev, "Could not enable slow clock\n"); + return ret; + } + mr = rtt_readl(rtc, MR); /* unless RTT is counting at 1 Hz, re-initialize it */ - if ((mr & AT91_RTT_RTPRES) != AT91_SLOW_CLOCK) { - mr = AT91_RTT_RTTRST | (AT91_SLOW_CLOCK & AT91_RTT_RTPRES); + if ((mr & AT91_RTT_RTPRES) != sclk_rate) { + mr = AT91_RTT_RTTRST | (sclk_rate & AT91_RTT_RTPRES); gpbr_writel(rtc, 0); } @@ -383,6 +451,9 @@ static int at91_rtc_remove(struct platform_device *pdev) /* disable all interrupts */ rtt_writel(rtc, MR, mr & ~(AT91_RTT_ALMIEN | AT91_RTT_RTTINCIEN)); + if (!IS_ERR(rtc->sclk)) + clk_disable_unprepare(rtc->sclk); + return 0; } @@ -440,6 +511,14 @@ static int at91_rtc_resume(struct device *dev) static SIMPLE_DEV_PM_OPS(at91_rtc_pm_ops, at91_rtc_suspend, at91_rtc_resume); +#ifdef CONFIG_OF +static const struct of_device_id at91_rtc_dt_ids[] = { + { .compatible = "atmel,at91sam9260-rtt" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, at91_rtc_dt_ids); +#endif + static struct platform_driver at91_rtc_driver = { .probe = at91_rtc_probe, .remove = at91_rtc_remove, @@ -448,6 +527,7 @@ static struct platform_driver at91_rtc_driver = { .name = "rtc-at91sam9", .owner = THIS_MODULE, .pm = &at91_rtc_pm_ops, + .of_match_table = of_match_ptr(at91_rtc_dt_ids), }, }; |