1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * drivers/clk/at91/clk-slow.c 4 * 5 * Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com> 6 */ 7 8 #include <linux/clk-provider.h> 9 #include <linux/clkdev.h> 10 #include <linux/clk/at91_pmc.h> 11 #include <linux/of.h> 12 #include <linux/mfd/syscon.h> 13 #include <linux/regmap.h> 14 15 #include "pmc.h" 16 17 struct clk_sam9260_slow { 18 struct clk_hw hw; 19 struct regmap *regmap; 20 }; 21 22 #define to_clk_sam9260_slow(hw) container_of(hw, struct clk_sam9260_slow, hw) 23 24 static u8 clk_sam9260_slow_get_parent(struct clk_hw *hw) 25 { 26 struct clk_sam9260_slow *slowck = to_clk_sam9260_slow(hw); 27 unsigned int status; 28 29 regmap_read(slowck->regmap, AT91_PMC_SR, &status); 30 31 return status & AT91_PMC_OSCSEL ? 1 : 0; 32 } 33 34 static const struct clk_ops sam9260_slow_ops = { 35 .get_parent = clk_sam9260_slow_get_parent, 36 }; 37 38 struct clk_hw * __init 39 at91_clk_register_sam9260_slow(struct regmap *regmap, 40 const char *name, 41 const char **parent_names, 42 int num_parents) 43 { 44 struct clk_sam9260_slow *slowck; 45 struct clk_hw *hw; 46 struct clk_init_data init; 47 int ret; 48 49 if (!name) 50 return ERR_PTR(-EINVAL); 51 52 if (!parent_names || !num_parents) 53 return ERR_PTR(-EINVAL); 54 55 slowck = kzalloc(sizeof(*slowck), GFP_KERNEL); 56 if (!slowck) 57 return ERR_PTR(-ENOMEM); 58 59 init.name = name; 60 init.ops = &sam9260_slow_ops; 61 init.parent_names = parent_names; 62 init.num_parents = num_parents; 63 init.flags = 0; 64 65 slowck->hw.init = &init; 66 slowck->regmap = regmap; 67 68 hw = &slowck->hw; 69 ret = clk_hw_register(NULL, &slowck->hw); 70 if (ret) { 71 kfree(slowck); 72 hw = ERR_PTR(ret); 73 } 74 75 return hw; 76 } 77