#include <linux/slab.h>
#include <linux/platform_data/atmel.h>
#include <linux/io.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
#define AT91_RTT_ALMS (1 << 0) /* Real-time Alarm Status */
#define AT91_RTT_RTTINC (1 << 1) /* Real-time Timer Increment */
-#define AT91_SLOW_CLOCK 32768
-
/*
* We store ALARM_DISABLED in ALMV to record that no alarm is set.
* It's also the reset value for that field.
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) \
#define rtt_writel(rtc, field, val) \
writel((val), (rtc)->rtt + AT91_RTT_ ## field)
-#define gpbr_readl(rtc) \
- readl((rtc)->gpbr)
-#define gpbr_writel(rtc, val) \
- writel((val), (rtc)->gpbr)
+static inline unsigned int gpbr_readl(struct sam9_rtc *rtc)
+{
+ unsigned int val;
+
+ regmap_read(rtc->gpbr, rtc->gpbr_offset, &val);
+
+ 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
.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) {
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);
}
/* 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;
}
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,
.name = "rtc-at91sam9",
.owner = THIS_MODULE,
.pm = &at91_rtc_pm_ops,
+ .of_match_table = of_match_ptr(at91_rtc_dt_ids),
},
};
projects / firefly-linux-kernel-4.4.55.git / blobdiff