120 lines
2.7 KiB
C
120 lines
2.7 KiB
C
/*
|
|
* Copyright (C) 2014 Chen-Yu Tsai
|
|
* Author: Chen-Yu Tsai <wens@csie.org>
|
|
*
|
|
* Allwinner A23 APB0 clock driver
|
|
*
|
|
* License Terms: GNU General Public License v2
|
|
*
|
|
* Based on clk-sun6i-apb0.c
|
|
* Allwinner A31 APB0 clock driver
|
|
*
|
|
* Copyright (C) 2014 Free Electrons
|
|
* Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
|
|
*
|
|
*/
|
|
|
|
#include <linux/clk-provider.h>
|
|
#include <linux/init.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/platform_device.h>
|
|
|
|
static struct clk *sun8i_a23_apb0_register(struct device_node *node,
|
|
void __iomem *reg)
|
|
{
|
|
const char *clk_name = node->name;
|
|
const char *clk_parent;
|
|
struct clk *clk;
|
|
int ret;
|
|
|
|
clk_parent = of_clk_get_parent_name(node, 0);
|
|
if (!clk_parent)
|
|
return ERR_PTR(-EINVAL);
|
|
|
|
of_property_read_string(node, "clock-output-names", &clk_name);
|
|
|
|
/* The A23 APB0 clock is a standard 2 bit wide divider clock */
|
|
clk = clk_register_divider(NULL, clk_name, clk_parent, 0, reg,
|
|
0, 2, 0, NULL);
|
|
if (IS_ERR(clk))
|
|
return clk;
|
|
|
|
ret = of_clk_add_provider(node, of_clk_src_simple_get, clk);
|
|
if (ret)
|
|
goto err_unregister;
|
|
|
|
return clk;
|
|
|
|
err_unregister:
|
|
clk_unregister_divider(clk);
|
|
|
|
return ERR_PTR(ret);
|
|
}
|
|
|
|
static void sun8i_a23_apb0_setup(struct device_node *node)
|
|
{
|
|
void __iomem *reg;
|
|
struct resource res;
|
|
struct clk *clk;
|
|
|
|
reg = of_io_request_and_map(node, 0, of_node_full_name(node));
|
|
if (IS_ERR(reg)) {
|
|
/*
|
|
* This happens with clk nodes instantiated through mfd,
|
|
* as those do not have their resources assigned in the
|
|
* device tree. Do not print an error in this case.
|
|
*/
|
|
if (PTR_ERR(reg) != -EINVAL)
|
|
pr_err("Could not get registers for a23-apb0-clk\n");
|
|
|
|
return;
|
|
}
|
|
|
|
clk = sun8i_a23_apb0_register(node, reg);
|
|
if (IS_ERR(clk))
|
|
goto err_unmap;
|
|
|
|
return;
|
|
|
|
err_unmap:
|
|
iounmap(reg);
|
|
of_address_to_resource(node, 0, &res);
|
|
release_mem_region(res.start, resource_size(&res));
|
|
}
|
|
CLK_OF_DECLARE(sun8i_a23_apb0, "allwinner,sun8i-a23-apb0-clk",
|
|
sun8i_a23_apb0_setup);
|
|
|
|
static int sun8i_a23_apb0_clk_probe(struct platform_device *pdev)
|
|
{
|
|
struct device_node *np = pdev->dev.of_node;
|
|
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 = sun8i_a23_apb0_register(np, reg);
|
|
if (IS_ERR(clk))
|
|
return PTR_ERR(clk);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct of_device_id sun8i_a23_apb0_clk_dt_ids[] = {
|
|
{ .compatible = "allwinner,sun8i-a23-apb0-clk" },
|
|
{ /* sentinel */ }
|
|
};
|
|
|
|
static struct platform_driver sun8i_a23_apb0_clk_driver = {
|
|
.driver = {
|
|
.name = "sun8i-a23-apb0-clk",
|
|
.of_match_table = sun8i_a23_apb0_clk_dt_ids,
|
|
},
|
|
.probe = sun8i_a23_apb0_clk_probe,
|
|
};
|
|
builtin_platform_driver(sun8i_a23_apb0_clk_driver);
|