[PATCH 11/11] clocksource: flexcard: Support timestamp trigger selection

[Holger Dengler <dengler@linutronix.de>]

From: Benedikt Spranger <b.spranger@linutronix.de>

The Flexcard timestamp counter can be triggered from two external
trigger inputs or an internal clock at 1 MHz, 10 Mhz or 100 MHz.
Add support for timestamp trigger selection.

Signed-off-by: Holger Dengler <dengler@linutronix.de>
Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
cc: Daniel Lezcano <daniel.lezcano@linaro.org>
cc: Thomas Gleixner <tglx@linutronix.de>
---
 drivers/clocksource/flexcard-time.c | 50 ++++++++++++++++++++++++++++++++++---
 include/uapi/linux/flexcard.h       | 16 ++++++++++++
 2 files changed, 63 insertions(+), 3 deletions(-)

diff --git a/drivers/clocksource/flexcard-time.c b/drivers/clocksource/flexcard-time.c
index f2efb53..101a989 100644
--- a/drivers/clocksource/flexcard-time.c
+++ b/drivers/clocksource/flexcard-time.c
@@ -12,6 +12,7 @@
 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/init.h>
+#include <linux/flexcard.h>
 #include <linux/fs.h>
 #include <linux/miscdevice.h>
 #include <linux/platform_device.h>
@@ -26,8 +27,10 @@ static dev_t flexcard_clk_devt;
 static struct class *flexcard_clk_class;
 
 struct flexcard_clk {
+	struct flexcard_clk_desc desc;
 	struct posix_clock clock;
 	dev_t devid;
+	u32 mul;
 	struct device *dev;
 	void __iomem *ts64;
 	void __iomem *reset;
@@ -35,8 +38,9 @@ struct flexcard_clk {
 
 static int flexcard_clk_getres(struct posix_clock *pc, struct timespec *tp)
 {
+	struct flexcard_clk *clk = container_of(pc, struct flexcard_clk, clock);
 	tp->tv_sec = 0;
-	tp->tv_nsec = 1000;
+	tp->tv_nsec = clk->mul;
 
 	return 0;
 }
@@ -54,7 +58,7 @@ retry:
 		goto retry;
 
 	tp->tv_sec = div_u64_rem(now, clk->desc.freq, &rem);
-	tp->tv_nsec = rem * 1000;
+	tp->tv_nsec = rem * clk->mul;
 
 	return 0;
 }
@@ -73,11 +77,48 @@ static int flexcard_clk_settime(struct posix_clock *pc,
 	return 0;
 }
 
+static long flexcard_clk_ioctl(struct posix_clock *pc, unsigned int cmd,
+			       unsigned long arg)
+{
+	struct flexcard_clk *clk = container_of(pc, struct flexcard_clk, clock);
+	struct flexcard_clk_desc desc;
+
+	if (copy_from_user(&desc, (void __user *)arg, sizeof(desc)))
+		return -EFAULT;
+
+	switch (cmd) {
+	case FLEXCARD_CLK_1MHZ:
+		clk->desc.freq = 1000000;
+		break;
+	case FLEXCARD_CLK_10MHZ:
+		clk->desc.freq = 10000000;
+		break;
+	case FLEXCARD_CLK_100MHZ:
+		clk->desc.freq = 100000000;
+		break;
+	case FLEXCARD_CLK_EXT1:
+	case FLEXCARD_CLK_EXT2:
+		if (desc.freq < 1 || desc.freq > NSEC_PER_SEC)
+			return -EINVAL;
+		break;
+	default:
+		return -ENOTTY;
+	}
+
+	clk->desc = desc;
+	clk->mul = NSEC_PER_SEC/desc.freq;
+	writel(clk->desc.type, clk->ts64 + CLKSEL_OFF);
+	writel(FLEXCARD_RST_TS, clk->reset);
+
+	return 0;
+}
+
 static struct posix_clock_operations flexcard_clk_ops = {
 	.owner		= THIS_MODULE,
 	.clock_getres	= flexcard_clk_getres,
 	.clock_gettime	= flexcard_clk_gettime,
 	.clock_settime	= flexcard_clk_settime,
+	.ioctl		= flexcard_clk_ioctl,
 };
 
 static int flexcard_clksrc_iomap(struct platform_device *pdev)
@@ -134,8 +175,11 @@ static int flexcard_clksrc_probe(struct platform_device *pdev)
 
 	clk->devid = MKDEV(major, cell->id);
 	clk->clock.ops = flexcard_clk_ops;
+	clk->desc.type = FLEXCARD_CLK_1MHZ;
+	clk->desc.freq = 1000000;
+	clk->mul = 1000;
 
-	writel(FLEXCARD_CLK_1MHZ, clk->ts64 + CLKSEL_OFF);
+	writel(clk->desc.type, clk->ts64 + CLKSEL_OFF);
 	writel(FLEXCARD_RST_TS, clk->reset);
 
 	clk->dev = device_create(flexcard_clk_class, &pdev->dev, clk->devid,
diff --git a/include/uapi/linux/flexcard.h b/include/uapi/linux/flexcard.h
index 9b73d8d..7939d94 100644
--- a/include/uapi/linux/flexcard.h
+++ b/include/uapi/linux/flexcard.h
@@ -15,6 +15,22 @@
 
 #include <linux/types.h>
 
+enum flexcard_clk_type {
+	FLEXCARD_CLK_1MHZ = 0x0,
+	FLEXCARD_CLK_10MHZ = 0x1,
+	FLEXCARD_CLK_100MHZ = 0x2,
+	FLEXCARD_CLK_EXT1 = 0x11,
+	FLEXCARD_CLK_EXT2 = 0x12,
+};
+
+struct flexcard_clk_desc {
+	enum flexcard_clk_type type;
+	__u32 freq;
+};
+
+#define FCGCLKSRC       _IOR(0xeb, 0, struct flexcard_clk_desc)
+#define FCSCLKSRC       _IOW(0xeb, 1, struct flexcard_clk_desc)
+
 struct fc_version {
 	__u8	dev;
 	__u8	min;
-- 
2.1.4