linux/drivers/clk/h8300/clk-div.c

58 lines
1.4 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* H8/300 divide clock driver
*
* Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp>
*/
#include <linux/clk-provider.h>
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of.h>
#include <linux/of_address.h>
static DEFINE_SPINLOCK(clklock);
static void __init h8300_div_clk_setup(struct device_node *node)
{
unsigned int num_parents;
struct clk_hw *hw;
const char *clk_name = node->name;
const char *parent_name;
void __iomem *divcr = NULL;
int width;
int offset;
num_parents = of_clk_get_parent_count(node);
if (!num_parents) {
pr_err("%s: no parent found\n", clk_name);
return;
}
divcr = of_iomap(node, 0);
if (divcr == NULL) {
pr_err("%s: failed to map divide register\n", clk_name);
goto error;
}
offset = (unsigned long)divcr & 3;
offset = (3 - offset) * 8;
divcr = (void __iomem *)((unsigned long)divcr & ~3);
parent_name = of_clk_get_parent_name(node, 0);
of_property_read_u32(node, "renesas,width", &width);
hw = clk_hw_register_divider(NULL, clk_name, parent_name,
CLK_SET_RATE_GATE, divcr, offset, width,
CLK_DIVIDER_POWER_OF_TWO, &clklock);
if (!IS_ERR(hw)) {
of_clk_add_hw_provider(node, of_clk_hw_simple_get, hw);
return;
}
pr_err("%s: failed to register %s div clock (%ld)\n",
__func__, clk_name, PTR_ERR(hw));
error:
if (divcr)
iounmap(divcr);
}
CLK_OF_DECLARE(h8300_div_clk, "renesas,h8300-div-clock", h8300_div_clk_setup);