Paul Walmsley | 21325b25 | 2012-10-21 01:01:12 -0600 | [diff] [blame] | 1 | /* |
| 2 | * OMAP2+ common Clock Management (CM) IP block functions |
| 3 | * |
| 4 | * Copyright (C) 2012 Texas Instruments, Inc. |
| 5 | * Paul Walmsley <paul@pwsan.com> |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or modify |
| 8 | * it under the terms of the GNU General Public License version 2 as |
| 9 | * published by the Free Software Foundation. |
| 10 | * |
| 11 | * XXX This code should eventually be moved to a CM driver. |
| 12 | */ |
| 13 | |
| 14 | #include <linux/kernel.h> |
| 15 | #include <linux/init.h> |
| 16 | |
| 17 | #include "cm2xxx.h" |
| 18 | #include "cm3xxx.h" |
| 19 | #include "cm44xx.h" |
| 20 | |
| 21 | /* |
| 22 | * cm_ll_data: function pointers to SoC-specific implementations of |
| 23 | * common CM functions |
| 24 | */ |
| 25 | static struct cm_ll_data null_cm_ll_data; |
| 26 | static struct cm_ll_data *cm_ll_data = &null_cm_ll_data; |
| 27 | |
| 28 | /** |
| 29 | * cm_register - register per-SoC low-level data with the CM |
| 30 | * @cld: low-level per-SoC OMAP CM data & function pointers to register |
| 31 | * |
| 32 | * Register per-SoC low-level OMAP CM data and function pointers with |
| 33 | * the OMAP CM common interface. The caller must keep the data |
| 34 | * pointed to by @cld valid until it calls cm_unregister() and |
| 35 | * it returns successfully. Returns 0 upon success, -EINVAL if @cld |
| 36 | * is NULL, or -EEXIST if cm_register() has already been called |
| 37 | * without an intervening cm_unregister(). |
| 38 | */ |
| 39 | int cm_register(struct cm_ll_data *cld) |
| 40 | { |
| 41 | if (!cld) |
| 42 | return -EINVAL; |
| 43 | |
| 44 | if (cm_ll_data != &null_cm_ll_data) |
| 45 | return -EEXIST; |
| 46 | |
| 47 | cm_ll_data = cld; |
| 48 | |
| 49 | return 0; |
| 50 | } |
| 51 | |
| 52 | /** |
| 53 | * cm_unregister - unregister per-SoC low-level data & function pointers |
| 54 | * @cld: low-level per-SoC OMAP CM data & function pointers to unregister |
| 55 | * |
| 56 | * Unregister per-SoC low-level OMAP CM data and function pointers |
| 57 | * that were previously registered with cm_register(). The |
| 58 | * caller may not destroy any of the data pointed to by @cld until |
| 59 | * this function returns successfully. Returns 0 upon success, or |
| 60 | * -EINVAL if @cld is NULL or if @cld does not match the struct |
| 61 | * cm_ll_data * previously registered by cm_register(). |
| 62 | */ |
| 63 | int cm_unregister(struct cm_ll_data *cld) |
| 64 | { |
| 65 | if (!cld || cm_ll_data != cld) |
| 66 | return -EINVAL; |
| 67 | |
| 68 | cm_ll_data = &null_cm_ll_data; |
| 69 | |
| 70 | return 0; |
| 71 | } |