1 /* 2 * Copyright (c) 2015 Google, Inc 3 * Written by Simon Glass <sjg@chromium.org> 4 * Copyright (c) 2016, NVIDIA CORPORATION. 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 #ifndef _CLK_UCLASS_H 10 #define _CLK_UCLASS_H 11 12 /* See clk.h for background documentation. */ 13 14 #include <clk.h> 15 16 struct ofnode_phandle_args; 17 18 /** 19 * struct clk_ops - The functions that a clock driver must implement. 20 */ 21 struct clk_ops { 22 /** 23 * of_xlate - Translate a client's device-tree (OF) clock specifier. 24 * 25 * The clock core calls this function as the first step in implementing 26 * a client's clk_get_by_*() call. 27 * 28 * If this function pointer is set to NULL, the clock core will use a 29 * default implementation, which assumes #clock-cells = <1>, and that 30 * the DT cell contains a simple integer clock ID. 31 * 32 * At present, the clock API solely supports device-tree. If this 33 * changes, other xxx_xlate() functions may be added to support those 34 * other mechanisms. 35 * 36 * @clock: The clock struct to hold the translation result. 37 * @args: The clock specifier values from device tree. 38 * @return 0 if OK, or a negative error code. 39 */ 40 int (*of_xlate)(struct clk *clock, 41 struct ofnode_phandle_args *args); 42 /** 43 * request - Request a translated clock. 44 * 45 * The clock core calls this function as the second step in 46 * implementing a client's clk_get_by_*() call, following a successful 47 * xxx_xlate() call, or as the only step in implementing a client's 48 * clk_request() call. 49 * 50 * @clock: The clock struct to request; this has been fille in by 51 * a previoux xxx_xlate() function call, or by the caller 52 * of clk_request(). 53 * @return 0 if OK, or a negative error code. 54 */ 55 int (*request)(struct clk *clock); 56 /** 57 * free - Free a previously requested clock. 58 * 59 * This is the implementation of the client clk_free() API. 60 * 61 * @clock: The clock to free. 62 * @return 0 if OK, or a negative error code. 63 */ 64 int (*free)(struct clk *clock); 65 /** 66 * get_rate() - Get current clock rate. 67 * 68 * @clk: The clock to query. 69 * @return clock rate in Hz, or -ve error code 70 */ 71 ulong (*get_rate)(struct clk *clk); 72 /** 73 * set_rate() - Set current clock rate. 74 * 75 * @clk: The clock to manipulate. 76 * @rate: New clock rate in Hz. 77 * @return new rate, or -ve error code. 78 */ 79 ulong (*set_rate)(struct clk *clk, ulong rate); 80 /** 81 * enable() - Enable a clock. 82 * 83 * @clk: The clock to manipulate. 84 * @return zero on success, or -ve error code. 85 */ 86 int (*enable)(struct clk *clk); 87 /** 88 * disable() - Disable a clock. 89 * 90 * @clk: The clock to manipulate. 91 * @return zero on success, or -ve error code. 92 */ 93 int (*disable)(struct clk *clk); 94 }; 95 96 #endif 97