163 lines
3.6 KiB
C
163 lines
3.6 KiB
C
#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>
|
|
#include <linux/slab.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_mem_region(r->start, ATMEL_TC_IOMEM_SIZE);
|
|
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_mem_region(tc->iomem->start, ATMEL_TC_IOMEM_SIZE);
|
|
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);
|