1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2018 Microchip Technology Inc, 4 * Codrin Ciubotariu <codrin.ciubotariu@microchip.com> 5 * 6 * 7 */ 8 9 #include <linux/clk-provider.h> 10 #include <linux/of.h> 11 #include <linux/mfd/syscon.h> 12 #include <linux/regmap.h> 13 #include <linux/slab.h> 14 15 #include <soc/at91/atmel-sfr.h> 16 17 #define I2S_BUS_NR 2 18 19 struct clk_i2s_mux { 20 struct clk_hw hw; 21 struct regmap *regmap; 22 u8 bus_id; 23 }; 24 25 #define to_clk_i2s_mux(hw) container_of(hw, struct clk_i2s_mux, hw) 26 27 static u8 clk_i2s_mux_get_parent(struct clk_hw *hw) 28 { 29 struct clk_i2s_mux *mux = to_clk_i2s_mux(hw); 30 u32 val; 31 32 regmap_read(mux->regmap, AT91_SFR_I2SCLKSEL, &val); 33 34 return (val & BIT(mux->bus_id)) >> mux->bus_id; 35 } 36 37 static int clk_i2s_mux_set_parent(struct clk_hw *hw, u8 index) 38 { 39 struct clk_i2s_mux *mux = to_clk_i2s_mux(hw); 40 41 return regmap_update_bits(mux->regmap, AT91_SFR_I2SCLKSEL, 42 BIT(mux->bus_id), index << mux->bus_id); 43 } 44 45 static const struct clk_ops clk_i2s_mux_ops = { 46 .get_parent = clk_i2s_mux_get_parent, 47 .set_parent = clk_i2s_mux_set_parent, 48 .determine_rate = __clk_mux_determine_rate, 49 }; 50 51 static struct clk_hw * __init 52 at91_clk_i2s_mux_register(struct regmap *regmap, const char *name, 53 const char * const *parent_names, 54 unsigned int num_parents, u8 bus_id) 55 { 56 struct clk_init_data init = {}; 57 struct clk_i2s_mux *i2s_ck; 58 int ret; 59 60 i2s_ck = kzalloc(sizeof(*i2s_ck), GFP_KERNEL); 61 if (!i2s_ck) 62 return ERR_PTR(-ENOMEM); 63 64 init.name = name; 65 init.ops = &clk_i2s_mux_ops; 66 init.parent_names = parent_names; 67 init.num_parents = num_parents; 68 69 i2s_ck->hw.init = &init; 70 i2s_ck->bus_id = bus_id; 71 i2s_ck->regmap = regmap; 72 73 ret = clk_hw_register(NULL, &i2s_ck->hw); 74 if (ret) { 75 kfree(i2s_ck); 76 return ERR_PTR(ret); 77 } 78 79 return &i2s_ck->hw; 80 } 81 82 static void __init of_sama5d2_clk_i2s_mux_setup(struct device_node *np) 83 { 84 struct regmap *regmap_sfr; 85 u8 bus_id; 86 const char *parent_names[2]; 87 struct device_node *i2s_mux_np; 88 struct clk_hw *hw; 89 int ret; 90 91 regmap_sfr = syscon_regmap_lookup_by_compatible("atmel,sama5d2-sfr"); 92 if (IS_ERR(regmap_sfr)) 93 return; 94 95 for_each_child_of_node(np, i2s_mux_np) { 96 if (of_property_read_u8(i2s_mux_np, "reg", &bus_id)) 97 continue; 98 99 if (bus_id > I2S_BUS_NR) 100 continue; 101 102 ret = of_clk_parent_fill(i2s_mux_np, parent_names, 2); 103 if (ret != 2) 104 continue; 105 106 hw = at91_clk_i2s_mux_register(regmap_sfr, i2s_mux_np->name, 107 parent_names, 2, bus_id); 108 if (IS_ERR(hw)) 109 continue; 110 111 of_clk_add_hw_provider(i2s_mux_np, of_clk_hw_simple_get, hw); 112 } 113 } 114 115 CLK_OF_DECLARE(sama5d2_clk_i2s_mux, "atmel,sama5d2-clk-i2s-mux", 116 of_sama5d2_clk_i2s_mux_setup); 117