M7350/kernel/drivers/misc/atmel_tclib.c
2024-09-09 08:57:42 +00:00

195 lines
4.4 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
*
* 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)
{
struct atmel_tc *tc;
struct platform_device *pdev = NULL;
spin_lock(&tc_list_lock);
list_for_each_entry(tc, &tc_list, node) {
if (tc->allocated)
continue;
if ((tc->pdev->dev.of_node && tc->id == block) ||
(tc->pdev->id == block)) {
pdev = tc->pdev;
tc->allocated = true;
break;
}
}
spin_unlock(&tc_list_lock);
return pdev ? tc : NULL;
}
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(), 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->allocated)
tc->allocated = false;
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;
struct resource *r;
unsigned int i;
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -EINVAL;
tc = devm_kzalloc(&pdev->dev, sizeof(struct atmel_tc), GFP_KERNEL);
if (!tc)
return -ENOMEM;
tc->pdev = pdev;
clk = devm_clk_get(&pdev->dev, "t0_clk");
if (IS_ERR(clk))
return PTR_ERR(clk);
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
tc->regs = devm_ioremap_resource(&pdev->dev, r);
if (IS_ERR(tc->regs))
return PTR_ERR(tc->regs);
/* 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->id = of_alias_get_id(tc->pdev->dev.of_node, "tcb");
} else {
tc->id = pdev->id;
}
tc->clk[0] = clk;
tc->clk[1] = devm_clk_get(&pdev->dev, "t1_clk");
if (IS_ERR(tc->clk[1]))
tc->clk[1] = clk;
tc->clk[2] = devm_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;
for (i = 0; i < 3; i++)
writel(ATMEL_TC_ALL_IRQ, tc->regs + ATMEL_TC_REG(i, IDR));
spin_lock(&tc_list_lock);
list_add_tail(&tc->node, &tc_list);
spin_unlock(&tc_list_lock);
platform_set_drvdata(pdev, tc);
return 0;
}
static void tc_shutdown(struct platform_device *pdev)
{
int i;
struct atmel_tc *tc = platform_get_drvdata(pdev);
for (i = 0; i < 3; i++)
writel(ATMEL_TC_ALL_IRQ, tc->regs + ATMEL_TC_REG(i, IDR));
}
static struct platform_driver tc_driver = {
.driver = {
.name = "atmel_tcb",
.of_match_table = of_match_ptr(atmel_tcb_dt_ids),
},
.shutdown = tc_shutdown,
};
static int __init tc_init(void)
{
return platform_driver_probe(&tc_driver, tc_probe);
}
arch_initcall(tc_init);