include/clk.h

   1 /*
   2  * Copyright (c) 2015 Google, Inc
   3  * Written by Simon Glass <sjg@chromium.org>
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 #ifndef _CLK_H_
   9 #define _CLK_H_
  10
  11 #include <errno.h>
  12 #include <linux/types.h>
  13
  14 struct udevice;
  15
  16 int soc_clk_dump(void);
  17
  18 struct clk_ops {
  19         /**
  20          * get_rate() - Get current clock rate
  21          *
  22          * @dev:        Device to check (UCLASS_CLK)
  23          * @return clock rate in Hz, or -ve error code
  24          */
  25         ulong (*get_rate)(struct udevice *dev);
  26
  27         /**
  28          * set_rate() - Set current clock rate
  29          *
  30          * @dev:        Device to adjust
  31          * @rate:       New clock rate in Hz
  32          * @return new rate, or -ve error code
  33          */
  34         ulong (*set_rate)(struct udevice *dev, ulong rate);
  35
  36         /**
  37          * enable() - Enable the clock for a peripheral
  38          *
  39          * @dev:        clock provider
  40          * @periph:     Peripheral ID to enable
  41          * @return zero on success, or -ve error code
  42          */
  43         int (*enable)(struct udevice *dev, int periph);
  44
  45         /**
  46          * get_periph_rate() - Get clock rate for a peripheral
  47          *
  48          * @dev:        Device to check (UCLASS_CLK)
  49          * @periph:     Peripheral ID to check
  50          * @return clock rate in Hz, or -ve error code
  51          */
  52         ulong (*get_periph_rate)(struct udevice *dev, int periph);
  53
  54         /**
  55          * set_periph_rate() - Set current clock rate for a peripheral
  56          *
  57          * @dev:        Device to update (UCLASS_CLK)
  58          * @periph:     Peripheral ID to update
  59          * @return new clock rate in Hz, or -ve error code
  60          */
  61         ulong (*set_periph_rate)(struct udevice *dev, int periph, ulong rate);
  62 };
  63
  64 #define clk_get_ops(dev)        ((struct clk_ops *)(dev)->driver->ops)
  65
  66 /**
  67  * clk_get_rate() - Get current clock rate
  68  *
  69  * @dev:        Device to check (UCLASS_CLK)
  70  * @return clock rate in Hz, or -ve error code
  71  */
  72 ulong clk_get_rate(struct udevice *dev);
  73
  74 /**
  75  * clk_set_rate() - Set current clock rate
  76  *
  77  * @dev:        Device to adjust
  78  * @rate:       New clock rate in Hz
  79  * @return new rate, or -ve error code
  80  */
  81 ulong clk_set_rate(struct udevice *dev, ulong rate);
  82
  83 /**
  84  * clk_enable() - Enable the clock for a peripheral
  85  *
  86  * @dev:        clock provider
  87  * @periph:     Peripheral ID to enable
  88  * @return zero on success, or -ve error code
  89  */
  90 int clk_enable(struct udevice *dev, int periph);
  91
  92 /**
  93  * clk_get_periph_rate() - Get current clock rate for a peripheral
  94  *
  95  * @dev:        Device to check (UCLASS_CLK)
  96  * @return clock rate in Hz, -ve error code
  97  */
  98 ulong clk_get_periph_rate(struct udevice *dev, int periph);
  99
 100 /**
 101  * clk_set_periph_rate() - Set current clock rate for a peripheral
 102  *
 103  * @dev:        Device to update (UCLASS_CLK)
 104  * @periph:     Peripheral ID to update
 105  * @return new clock rate in Hz, or -ve error code
 106  */
 107 ulong clk_set_periph_rate(struct udevice *dev, int periph, ulong rate);
 108
 109 #if CONFIG_IS_ENABLED(OF_CONTROL)
 110 /**
 111  * clk_get_by_index() - look up a clock referenced by a device
 112  *
 113  * Parse a device's 'clocks' list, returning information on the indexed clock,
 114  * ensuring that it is activated.
 115  *
 116  * @dev:        Device containing the clock reference
 117  * @index:      Clock index to return (0 = first)
 118  * @clk_devp:   Returns clock device
 119  * @return:     Peripheral ID for the device to control. This is the first
 120  *              argument after the clock node phandle. If there is no arguemnt,
 121  *              returns 0. Return -ve error code on any error
 122  */
 123 int clk_get_by_index(struct udevice *dev, int index, struct udevice **clk_devp);
 124 #else
 125 static inline int clk_get_by_index(struct udevice *dev, int index,
 126                                    struct udevice **clk_devp)
 127 {
 128         return -ENOSYS;
 129 }
 130 #endif
 131
 132 #endif /* _CLK_H_ */