1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2012, NVIDIA CORPORATION. All rights reserved. 4 */ 5 6 #include <linux/clk-provider.h> 7 #include <linux/slab.h> 8 #include <linux/err.h> 9 10 #include "clk.h" 11 12 static unsigned long clk_sync_source_recalc_rate(struct clk_hw *hw, 13 unsigned long parent_rate) 14 { 15 struct tegra_clk_sync_source *sync = to_clk_sync_source(hw); 16 17 return sync->rate; 18 } 19 20 static long clk_sync_source_round_rate(struct clk_hw *hw, unsigned long rate, 21 unsigned long *prate) 22 { 23 struct tegra_clk_sync_source *sync = to_clk_sync_source(hw); 24 25 if (rate > sync->max_rate) 26 return -EINVAL; 27 else 28 return rate; 29 } 30 31 static int clk_sync_source_set_rate(struct clk_hw *hw, unsigned long rate, 32 unsigned long parent_rate) 33 { 34 struct tegra_clk_sync_source *sync = to_clk_sync_source(hw); 35 36 sync->rate = rate; 37 return 0; 38 } 39 40 const struct clk_ops tegra_clk_sync_source_ops = { 41 .round_rate = clk_sync_source_round_rate, 42 .set_rate = clk_sync_source_set_rate, 43 .recalc_rate = clk_sync_source_recalc_rate, 44 }; 45 46 struct clk *tegra_clk_register_sync_source(const char *name, 47 unsigned long max_rate) 48 { 49 struct tegra_clk_sync_source *sync; 50 struct clk_init_data init; 51 struct clk *clk; 52 53 sync = kzalloc(sizeof(*sync), GFP_KERNEL); 54 if (!sync) { 55 pr_err("%s: could not allocate sync source clk\n", __func__); 56 return ERR_PTR(-ENOMEM); 57 } 58 59 sync->max_rate = max_rate; 60 61 init.ops = &tegra_clk_sync_source_ops; 62 init.name = name; 63 init.flags = 0; 64 init.parent_names = NULL; 65 init.num_parents = 0; 66 67 /* Data in .init is copied by clk_register(), so stack variable OK */ 68 sync->hw.init = &init; 69 70 clk = clk_register(NULL, &sync->hw); 71 if (IS_ERR(clk)) 72 kfree(sync); 73 74 return clk; 75 } 76