summary refs log tree commit diff
path: root/drivers/misc
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/misc')
-rw-r--r--drivers/misc/Kconfig33
-rw-r--r--drivers/misc/Makefile1
-rw-r--r--drivers/misc/atmel_tclib.c161
3 files changed, 195 insertions, 0 deletions
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 962817e49fba..bb94ce78a6d0 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -22,6 +22,39 @@ config ATMEL_PWM
 	  purposes including software controlled power-efficent backlights
 	  on LCD displays, motor control, and waveform generation.
 
+config ATMEL_TCLIB
+	bool "Atmel AT32/AT91 Timer/Counter Library"
+	depends on (AVR32 || ARCH_AT91)
+	help
+	  Select this if you want a library to allocate the Timer/Counter
+	  blocks found on many Atmel processors.  This facilitates using
+	  these blocks by different drivers despite processor differences.
+
+config ATMEL_TCB_CLKSRC
+	bool "TC Block Clocksource"
+	depends on ATMEL_TCLIB && GENERIC_TIME
+	default y
+	help
+	  Select this to get a high precision clocksource based on a
+	  TC block with a 5+ MHz base clock rate.  Two timer channels
+	  are combined to make a single 32-bit timer.
+
+	  When GENERIC_CLOCKEVENTS is defined, the third timer channel
+	  may be used as a clock event device supporting oneshot mode
+	  (delays of up to two seconds) based on the 32 KiHz clock.
+
+config ATMEL_TCB_CLKSRC_BLOCK
+	int
+	depends on ATMEL_TCB_CLKSRC
+	prompt "TC Block" if ARCH_AT91RM9200 || ARCH_AT91SAM9260 || CPU_AT32AP700X
+	default 0
+	range 0 1
+	help
+	  Some chips provide more than one TC block, so you have the
+	  choice of which one to use for the clock framework.  The other
+	  TC can be used for other purposes, such as PWM generation and
+	  interval timing.
+
 config IBM_ASM
 	tristate "Device driver for IBM RSA service processor"
 	depends on X86 && PCI && INPUT && EXPERIMENTAL
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index bbc69fdd1b9d..4581b2533111 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -10,6 +10,7 @@ obj-$(CONFIG_ACER_WMI)     += acer-wmi.o
 obj-$(CONFIG_ASUS_LAPTOP)     += asus-laptop.o
 obj-$(CONFIG_ATMEL_PWM)		+= atmel_pwm.o
 obj-$(CONFIG_ATMEL_SSC)		+= atmel-ssc.o
+obj-$(CONFIG_ATMEL_TCLIB)	+= atmel_tclib.o
 obj-$(CONFIG_TC1100_WMI)	+= tc1100-wmi.o
 obj-$(CONFIG_LKDTM)		+= lkdtm.o
 obj-$(CONFIG_TIFM_CORE)       	+= tifm_core.o
diff --git a/drivers/misc/atmel_tclib.c b/drivers/misc/atmel_tclib.c
new file mode 100644
index 000000000000..05dc8a31f280
--- /dev/null
+++ b/drivers/misc/atmel_tclib.c
@@ -0,0 +1,161 @@
+#include <linux/atmel_tc.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+
+/* Number of bytes to reserve for the iomem resource */
+#define ATMEL_TC_IOMEM_SIZE	256
+
+
+/*
+ * This is a thin library to solve the problem of how to portably allocate
+ * one of the TC blocks.  For simplicity, it doesn't currently expect to
+ * share individual timers between different drivers.
+ */
+
+#if defined(CONFIG_AVR32)
+/* AVR32 has these divide PBB */
+const u8 atmel_tc_divisors[5] = { 0, 4, 8, 16, 32, };
+EXPORT_SYMBOL(atmel_tc_divisors);
+
+#elif defined(CONFIG_ARCH_AT91)
+/* AT91 has these divide MCK */
+const u8 atmel_tc_divisors[5] = { 2, 8, 32, 128, 0, };
+EXPORT_SYMBOL(atmel_tc_divisors);
+
+#endif
+
+static DEFINE_SPINLOCK(tc_list_lock);
+static LIST_HEAD(tc_list);
+
+/**
+ * atmel_tc_alloc - allocate a specified TC block
+ * @block: which block to allocate
+ * @name: name to be associated with the iomem resource
+ *
+ * Caller allocates a block.  If it is available, a pointer to a
+ * pre-initialized struct atmel_tc is returned. The caller can access
+ * the registers directly through the "regs" field.
+ */
+struct atmel_tc *atmel_tc_alloc(unsigned block, const char *name)
+{
+	struct atmel_tc		*tc;
+	struct platform_device	*pdev = NULL;
+	struct resource		*r;
+
+	spin_lock(&tc_list_lock);
+	list_for_each_entry(tc, &tc_list, node) {
+		if (tc->pdev->id == block) {
+			pdev = tc->pdev;
+			break;
+		}
+	}
+
+	if (!pdev || tc->iomem)
+		goto fail;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	r = request_mem_region(r->start, ATMEL_TC_IOMEM_SIZE, name);
+	if (!r)
+		goto fail;
+
+	tc->regs = ioremap(r->start, ATMEL_TC_IOMEM_SIZE);
+	if (!tc->regs)
+		goto fail_ioremap;
+
+	tc->iomem = r;
+
+out:
+	spin_unlock(&tc_list_lock);
+	return tc;
+
+fail_ioremap:
+	release_resource(r);
+fail:
+	tc = NULL;
+	goto out;
+}
+EXPORT_SYMBOL_GPL(atmel_tc_alloc);
+
+/**
+ * atmel_tc_free - release a specified TC block
+ * @tc: Timer/counter block that was returned by atmel_tc_alloc()
+ *
+ * This reverses the effect of atmel_tc_alloc(), unmapping the I/O
+ * registers, invalidating the resource returned by that routine and
+ * making the TC available to other drivers.
+ */
+void atmel_tc_free(struct atmel_tc *tc)
+{
+	spin_lock(&tc_list_lock);
+	if (tc->regs) {
+		iounmap(tc->regs);
+		release_resource(tc->iomem);
+		tc->regs = NULL;
+		tc->iomem = NULL;
+	}
+	spin_unlock(&tc_list_lock);
+}
+EXPORT_SYMBOL_GPL(atmel_tc_free);
+
+static int __init tc_probe(struct platform_device *pdev)
+{
+	struct atmel_tc *tc;
+	struct clk	*clk;
+	int		irq;
+
+	if (!platform_get_resource(pdev, IORESOURCE_MEM, 0))
+		return -EINVAL;
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0)
+		return -EINVAL;
+
+	tc = kzalloc(sizeof(struct atmel_tc), GFP_KERNEL);
+	if (!tc)
+		return -ENOMEM;
+
+	tc->pdev = pdev;
+
+	clk = clk_get(&pdev->dev, "t0_clk");
+	if (IS_ERR(clk)) {
+		kfree(tc);
+		return -EINVAL;
+	}
+
+	tc->clk[0] = clk;
+	tc->clk[1] = clk_get(&pdev->dev, "t1_clk");
+	if (IS_ERR(tc->clk[1]))
+		tc->clk[1] = clk;
+	tc->clk[2] = clk_get(&pdev->dev, "t2_clk");
+	if (IS_ERR(tc->clk[2]))
+		tc->clk[2] = clk;
+
+	tc->irq[0] = irq;
+	tc->irq[1] = platform_get_irq(pdev, 1);
+	if (tc->irq[1] < 0)
+		tc->irq[1] = irq;
+	tc->irq[2] = platform_get_irq(pdev, 2);
+	if (tc->irq[2] < 0)
+		tc->irq[2] = irq;
+
+	spin_lock(&tc_list_lock);
+	list_add_tail(&tc->node, &tc_list);
+	spin_unlock(&tc_list_lock);
+
+	return 0;
+}
+
+static struct platform_driver tc_driver = {
+	.driver.name	= "atmel_tcb",
+};
+
+static int __init tc_init(void)
+{
+	return platform_driver_probe(&tc_driver, tc_probe);
+}
+arch_initcall(tc_init);