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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-09 23:48:22 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-09 23:48:22 +0100
commit3a647c1d7ab08145cee4b650f5e797d168846c51 (patch)
tree6fcbc8ad1fc69b5a99214e22f6084452bdf0131c /drivers/rtc/rtc-at91sam9.c
parentMerge tag 'soc-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ar... (diff)
parentMerge branch 'at91/cleanup5' into next/drivers (diff)
downloadlinux-3a647c1d7ab08145cee4b650f5e797d168846c51.tar.xz
linux-3a647c1d7ab08145cee4b650f5e797d168846c51.zip
Merge tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc
Pull ARM SoC driver updates from Arnd Bergmann: "These are changes for drivers that are intimately tied to some SoC and for some reason could not get merged through the respective subsystem maintainer tree. The largest single change here this time around is the Tegra iommu/memory controller driver, which gets updated to the new iommu DT binding. More drivers like this are likely to follow for the following merge window, but we should be able to do those through the iommu maintainer. Other notable changes are: - reset controller drivers from the reset maintainer (socfpga, sti, berlin) - fixes for the keystone navigator driver merged last time - at91 rtc driver changes related to the at91 cleanups - ARM perf driver changes from Will Deacon - updates for the brcmstb_gisb driver" * tag 'drivers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc: (53 commits) clocksource: arch_timer: Allow the device tree to specify uninitialized timer registers clocksource: arch_timer: Fix code to use physical timers when requested memory: Add NVIDIA Tegra memory controller support bus: brcmstb_gisb: Add register offset tables for older chips bus: brcmstb_gisb: Look up register offsets in a table bus: brcmstb_gisb: Introduce wrapper functions for MMIO accesses bus: brcmstb_gisb: Make the driver buildable on MIPS of: Add NVIDIA Tegra memory controller binding ARM: tegra: Move AHB Kconfig to drivers/amba amba: Add Kconfig file clk: tegra: Implement memory-controller clock serial: samsung: Fix serial config dependencies for exynos7 bus: brcmstb_gisb: resolve section mismatch ARM: common: edma: edma_pm_resume may be unused ARM: common: edma: add suspend resume hook powerpc/iommu: Rename iommu_[un]map_sg functions rtc: at91sam9: add DT bindings documentation rtc: at91sam9: use clk API instead of relying on AT91_SLOW_CLOCK ARM: at91: add clk_lookup entry for RTT devices rtc: at91sam9: rework the Kconfig description ...
Diffstat (limited to 'drivers/rtc/rtc-at91sam9.c')
-rw-r--r--drivers/rtc/rtc-at91sam9.c138
1 files changed, 109 insertions, 29 deletions
diff --git a/drivers/rtc/rtc-at91sam9.c b/drivers/rtc/rtc-at91sam9.c
index 596374304532..abac38abd38e 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),
},
};