95 lines
		
	
	
	
		
			2.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			95 lines
		
	
	
	
		
			2.3 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * Copyright 2014 Freescale Semiconductor, Inc. | ||
|  |  * | ||
|  |  * 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. | ||
|  |  */ | ||
|  | 
 | ||
|  | #include <linux/clk-provider.h>
 | ||
|  | #include <linux/err.h>
 | ||
|  | #include <linux/io.h>
 | ||
|  | #include <linux/slab.h>
 | ||
|  | #include "clk.h"
 | ||
|  | 
 | ||
|  | /**
 | ||
|  |  * struct clk_gate_exclusive - i.MX specific gate clock which is mutually | ||
|  |  * exclusive with other gate clocks | ||
|  |  * | ||
|  |  * @gate: the parent class | ||
|  |  * @exclusive_mask: mask of gate bits which are mutually exclusive to this | ||
|  |  *	gate clock | ||
|  |  * | ||
|  |  * The imx exclusive gate clock is a subclass of basic clk_gate | ||
|  |  * with an addtional mask to indicate which other gate bits in the same | ||
|  |  * register is mutually exclusive to this gate clock. | ||
|  |  */ | ||
|  | struct clk_gate_exclusive { | ||
|  | 	struct clk_gate gate; | ||
|  | 	u32 exclusive_mask; | ||
|  | }; | ||
|  | 
 | ||
|  | static int clk_gate_exclusive_enable(struct clk_hw *hw) | ||
|  | { | ||
|  | 	struct clk_gate *gate = container_of(hw, struct clk_gate, hw); | ||
|  | 	struct clk_gate_exclusive *exgate = container_of(gate, | ||
|  | 					struct clk_gate_exclusive, gate); | ||
|  | 	u32 val = readl(gate->reg); | ||
|  | 
 | ||
|  | 	if (val & exgate->exclusive_mask) | ||
|  | 		return -EBUSY; | ||
|  | 
 | ||
|  | 	return clk_gate_ops.enable(hw); | ||
|  | } | ||
|  | 
 | ||
|  | static void clk_gate_exclusive_disable(struct clk_hw *hw) | ||
|  | { | ||
|  | 	clk_gate_ops.disable(hw); | ||
|  | } | ||
|  | 
 | ||
|  | static int clk_gate_exclusive_is_enabled(struct clk_hw *hw) | ||
|  | { | ||
|  | 	return clk_gate_ops.is_enabled(hw); | ||
|  | } | ||
|  | 
 | ||
|  | static const struct clk_ops clk_gate_exclusive_ops = { | ||
|  | 	.enable = clk_gate_exclusive_enable, | ||
|  | 	.disable = clk_gate_exclusive_disable, | ||
|  | 	.is_enabled = clk_gate_exclusive_is_enabled, | ||
|  | }; | ||
|  | 
 | ||
|  | struct clk *imx_clk_gate_exclusive(const char *name, const char *parent, | ||
|  | 	 void __iomem *reg, u8 shift, u32 exclusive_mask) | ||
|  | { | ||
|  | 	struct clk_gate_exclusive *exgate; | ||
|  | 	struct clk_gate *gate; | ||
|  | 	struct clk *clk; | ||
|  | 	struct clk_init_data init; | ||
|  | 
 | ||
|  | 	if (exclusive_mask == 0) | ||
|  | 		return ERR_PTR(-EINVAL); | ||
|  | 
 | ||
|  | 	exgate = kzalloc(sizeof(*exgate), GFP_KERNEL); | ||
|  | 	if (!exgate) | ||
|  | 		return ERR_PTR(-ENOMEM); | ||
|  | 	gate = &exgate->gate; | ||
|  | 
 | ||
|  | 	init.name = name; | ||
|  | 	init.ops = &clk_gate_exclusive_ops; | ||
|  | 	init.flags = CLK_SET_RATE_PARENT; | ||
|  | 	init.parent_names = parent ? &parent : NULL; | ||
|  | 	init.num_parents = parent ? 1 : 0; | ||
|  | 
 | ||
|  | 	gate->reg = reg; | ||
|  | 	gate->bit_idx = shift; | ||
|  | 	gate->lock = &imx_ccm_lock; | ||
|  | 	gate->hw.init = &init; | ||
|  | 	exgate->exclusive_mask = exclusive_mask; | ||
|  | 
 | ||
|  | 	clk = clk_register(NULL, &gate->hw); | ||
|  | 	if (IS_ERR(clk)) | ||
|  | 		kfree(exgate); | ||
|  | 
 | ||
|  | 	return clk; | ||
|  | } |