linux-sg2042/drivers/clk/sunxi/clk-sun8i-mbus.c

119 lines
3.0 KiB
C

/*
* Copyright 2014 Chen-Yu Tsai
*
* Chen-Yu Tsai <wens@csie.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*/
#include <linux/clk.h>
#include <linux/clk-provider.h>
#include <linux/io.h>
#include <linux/slab.h>
#include <linux/spinlock.h>
#include <linux/of_address.h>
#define SUN8I_MBUS_ENABLE 31
#define SUN8I_MBUS_MUX_SHIFT 24
#define SUN8I_MBUS_MUX_MASK 0x3
#define SUN8I_MBUS_DIV_SHIFT 0
#define SUN8I_MBUS_DIV_WIDTH 3
#define SUN8I_MBUS_MAX_PARENTS 4
static DEFINE_SPINLOCK(sun8i_a23_mbus_lock);
static void __init sun8i_a23_mbus_setup(struct device_node *node)
{
int num_parents = of_clk_get_parent_count(node);
const char **parents;
const char *clk_name = node->name;
struct resource res;
struct clk_divider *div;
struct clk_gate *gate;
struct clk_mux *mux;
struct clk *clk;
void __iomem *reg;
int err;
parents = kcalloc(num_parents, sizeof(*parents), GFP_KERNEL);
if (!parents)
return;
reg = of_io_request_and_map(node, 0, of_node_full_name(node));
if (IS_ERR(reg)) {
pr_err("Could not get registers for sun8i-mbus-clk\n");
goto err_free_parents;
}
div = kzalloc(sizeof(*div), GFP_KERNEL);
if (!div)
goto err_unmap;
mux = kzalloc(sizeof(*mux), GFP_KERNEL);
if (!mux)
goto err_free_div;
gate = kzalloc(sizeof(*gate), GFP_KERNEL);
if (!gate)
goto err_free_mux;
of_property_read_string(node, "clock-output-names", &clk_name);
of_clk_parent_fill(node, parents, num_parents);
gate->reg = reg;
gate->bit_idx = SUN8I_MBUS_ENABLE;
gate->lock = &sun8i_a23_mbus_lock;
div->reg = reg;
div->shift = SUN8I_MBUS_DIV_SHIFT;
div->width = SUN8I_MBUS_DIV_WIDTH;
div->lock = &sun8i_a23_mbus_lock;
mux->reg = reg;
mux->shift = SUN8I_MBUS_MUX_SHIFT;
mux->mask = SUN8I_MBUS_MUX_MASK;
mux->lock = &sun8i_a23_mbus_lock;
/* The MBUS clocks needs to be always enabled */
clk = clk_register_composite(NULL, clk_name, parents, num_parents,
&mux->hw, &clk_mux_ops,
&div->hw, &clk_divider_ops,
&gate->hw, &clk_gate_ops,
CLK_IS_CRITICAL);
if (IS_ERR(clk))
goto err_free_gate;
err = of_clk_add_provider(node, of_clk_src_simple_get, clk);
if (err)
goto err_unregister_clk;
kfree(parents); /* parents is deep copied */
return;
err_unregister_clk:
/* TODO: The composite clock stuff will leak a bit here. */
clk_unregister(clk);
err_free_gate:
kfree(gate);
err_free_mux:
kfree(mux);
err_free_div:
kfree(div);
err_unmap:
iounmap(reg);
of_address_to_resource(node, 0, &res);
release_mem_region(res.start, resource_size(&res));
err_free_parents:
kfree(parents);
}
CLK_OF_DECLARE(sun8i_a23_mbus, "allwinner,sun8i-a23-mbus-clk", sun8i_a23_mbus_setup);