M7350/kernel/drivers/misc/atmel_tclib.c
2024-09-09 08:52:07 +00:00

208 lines
4.5 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/module.h>
#include <linux/slab.h>
#include <linux/export.h>
#include <linux/of.h>
/*
* 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;
size_t size;
spin_lock(&tc_list_lock);
list_for_each_entry(tc, &tc_list, node) {
if (tc->pdev->dev.of_node) {
if (of_alias_get_id(tc->pdev->dev.of_node, "tcb")
== block) {
pdev = tc->pdev;
break;
}
} else if (tc->pdev->id == block) {
pdev = tc->pdev;
break;
}
}
if (!pdev || tc->iomem)
goto fail;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!r)
goto fail;
size = resource_size(r);
r = request_mem_region(r->start, size, name);
if (!r)
goto fail;
tc->regs = ioremap(r->start, 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, 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, resource_size(tc->iomem));
tc->regs = NULL;
tc->iomem = NULL;
}
spin_unlock(&tc_list_lock);
}
EXPORT_SYMBOL_GPL(atmel_tc_free);
#if defined(CONFIG_OF)
static struct atmel_tcb_config tcb_rm9200_config = {
.counter_width = 16,
};
static struct atmel_tcb_config tcb_sam9x5_config = {
.counter_width = 32,
};
static const struct of_device_id atmel_tcb_dt_ids[] = {
{
.compatible = "atmel,at91rm9200-tcb",
.data = &tcb_rm9200_config,
}, {
.compatible = "atmel,at91sam9x5-tcb",
.data = &tcb_sam9x5_config,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(of, atmel_tcb_dt_ids);
#endif
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;
}
/* Now take SoC information if available */
if (pdev->dev.of_node) {
const struct of_device_id *match;
match = of_match_node(atmel_tcb_dt_ids, pdev->dev.of_node);
if (match)
tc->tcb_config = match->data;
}
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",
.of_match_table = of_match_ptr(atmel_tcb_dt_ids),
},
};
static int __init tc_init(void)
{
return platform_driver_probe(&tc_driver, tc_probe);
}
arch_initcall(tc_init);