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