| /* |
| * Copyright (c) 2014 Lucas Stach <l.stach@pengutronix.de>, Pengutronix |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License version 2 as |
| * published by the Free Software Foundation. |
| * |
| * http://www.opensource.org/licenses/gpl-license.html |
| * http://www.gnu.org/copyleft/gpl.html |
| */ |
| |
| #include <linux/clk.h> |
| #include <linux/clk-provider.h> |
| #include <linux/slab.h> |
| |
| struct clk_cpu { |
| struct clk_hw hw; |
| struct clk *div; |
| struct clk *mux; |
| struct clk *pll; |
| struct clk *step; |
| }; |
| |
| static inline struct clk_cpu *to_clk_cpu(struct clk_hw *hw) |
| { |
| return container_of(hw, struct clk_cpu, hw); |
| } |
| |
| static unsigned long clk_cpu_recalc_rate(struct clk_hw *hw, |
| unsigned long parent_rate) |
| { |
| struct clk_cpu *cpu = to_clk_cpu(hw); |
| |
| return clk_get_rate(cpu->div); |
| } |
| |
| static long clk_cpu_round_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long *prate) |
| { |
| struct clk_cpu *cpu = to_clk_cpu(hw); |
| |
| return clk_round_rate(cpu->pll, rate); |
| } |
| |
| static int clk_cpu_set_rate(struct clk_hw *hw, unsigned long rate, |
| unsigned long parent_rate) |
| { |
| struct clk_cpu *cpu = to_clk_cpu(hw); |
| int ret; |
| |
| /* switch to PLL bypass clock */ |
| ret = clk_set_parent(cpu->mux, cpu->step); |
| if (ret) |
| return ret; |
| |
| /* reprogram PLL */ |
| ret = clk_set_rate(cpu->pll, rate); |
| if (ret) { |
| clk_set_parent(cpu->mux, cpu->pll); |
| return ret; |
| } |
| /* switch back to PLL clock */ |
| clk_set_parent(cpu->mux, cpu->pll); |
| |
| /* Ensure the divider is what we expect */ |
| clk_set_rate(cpu->div, rate); |
| |
| return 0; |
| } |
| |
| static const struct clk_ops clk_cpu_ops = { |
| .recalc_rate = clk_cpu_recalc_rate, |
| .round_rate = clk_cpu_round_rate, |
| .set_rate = clk_cpu_set_rate, |
| }; |
| |
| struct clk *imx_clk_cpu(const char *name, const char *parent_name, |
| struct clk *div, struct clk *mux, struct clk *pll, |
| struct clk *step) |
| { |
| struct clk_cpu *cpu; |
| struct clk *clk; |
| struct clk_init_data init; |
| |
| cpu = kzalloc(sizeof(*cpu), GFP_KERNEL); |
| if (!cpu) |
| return ERR_PTR(-ENOMEM); |
| |
| cpu->div = div; |
| cpu->mux = mux; |
| cpu->pll = pll; |
| cpu->step = step; |
| |
| init.name = name; |
| init.ops = &clk_cpu_ops; |
| init.flags = 0; |
| init.parent_names = &parent_name; |
| init.num_parents = 1; |
| |
| cpu->hw.init = &init; |
| |
| clk = clk_register(NULL, &cpu->hw); |
| if (IS_ERR(clk)) |
| kfree(cpu); |
| |
| return clk; |
| } |