OpenCloudOS-Kernel/drivers/clk/sunxi/clk-sun6i-apb0.c

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/*
* Copyright (C) 2014 Free Electrons
*
* License Terms: GNU General Public License v2
* Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
*
* Allwinner A31 APB0 clock driver
*
*/
#include <linux/clk-provider.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
/*
* The APB0 clk has a configurable divisor.
*
* We must use a clk_div_table and not a regular power of 2
* divisor here, because the first 2 values divide the clock
* by 2.
*/
static const struct clk_div_table sun6i_a31_apb0_divs[] = {
{ .val = 0, .div = 2, },
{ .val = 1, .div = 2, },
{ .val = 2, .div = 4, },
{ .val = 3, .div = 8, },
{ /* sentinel */ },
};
static int sun6i_a31_apb0_clk_probe(struct platform_device *pdev)
{
struct device_node *np = pdev->dev.of_node;
const char *clk_name = np->name;
const char *clk_parent;
struct resource *r;
void __iomem *reg;
struct clk *clk;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
reg = devm_ioremap_resource(&pdev->dev, r);
if (IS_ERR(reg))
return PTR_ERR(reg);
clk_parent = of_clk_get_parent_name(np, 0);
if (!clk_parent)
return -EINVAL;
of_property_read_string(np, "clock-output-names", &clk_name);
clk = clk_register_divider_table(&pdev->dev, clk_name, clk_parent,
0, reg, 0, 2, 0, sun6i_a31_apb0_divs,
NULL);
if (IS_ERR(clk))
return PTR_ERR(clk);
return of_clk_add_provider(np, of_clk_src_simple_get, clk);
}
const struct of_device_id sun6i_a31_apb0_clk_dt_ids[] = {
{ .compatible = "allwinner,sun6i-a31-apb0-clk" },
{ /* sentinel */ }
};
static struct platform_driver sun6i_a31_apb0_clk_driver = {
.driver = {
.name = "sun6i-a31-apb0-clk",
.owner = THIS_MODULE,
.of_match_table = sun6i_a31_apb0_clk_dt_ids,
},
.probe = sun6i_a31_apb0_clk_probe,
};
module_platform_driver(sun6i_a31_apb0_clk_driver);
MODULE_AUTHOR("Boris BREZILLON <boris.brezillon@free-electrons.com>");
MODULE_DESCRIPTION("Allwinner A31 APB0 clock Driver");
MODULE_LICENSE("GPL v2");