diff options
Diffstat (limited to 'drivers/clk/sunxi/clk-sun8i-mbus.c')
| -rw-r--r-- | drivers/clk/sunxi/clk-sun8i-mbus.c | 117 |
1 files changed, 117 insertions, 0 deletions
diff --git a/drivers/clk/sunxi/clk-sun8i-mbus.c b/drivers/clk/sunxi/clk-sun8i-mbus.c new file mode 100644 index 000000000..56db89b69 --- /dev/null +++ b/drivers/clk/sunxi/clk-sun8i-mbus.c @@ -0,0 +1,117 @@ +/* + * 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/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); |