1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 */ 4 5 #define pr_fmt(fmt) "imx:clk-gpr-mux: " fmt 6 7 #include <linux/module.h> 8 9 #include <linux/clk-provider.h> 10 #include <linux/errno.h> 11 #include <linux/export.h> 12 #include <linux/io.h> 13 #include <linux/slab.h> 14 #include <linux/regmap.h> 15 #include <linux/mfd/syscon.h> 16 17 #include "clk.h" 18 19 struct imx_clk_gpr { 20 struct clk_hw hw; 21 struct regmap *regmap; 22 u32 mask; 23 u32 reg; 24 const u32 *mux_table; 25 }; 26 27 static struct imx_clk_gpr *to_imx_clk_gpr(struct clk_hw *hw) 28 { 29 return container_of(hw, struct imx_clk_gpr, hw); 30 } 31 32 static u8 imx_clk_gpr_mux_get_parent(struct clk_hw *hw) 33 { 34 struct imx_clk_gpr *priv = to_imx_clk_gpr(hw); 35 unsigned int val; 36 int ret; 37 38 ret = regmap_read(priv->regmap, priv->reg, &val); 39 if (ret) 40 goto get_parent_err; 41 42 val &= priv->mask; 43 44 ret = clk_mux_val_to_index(hw, priv->mux_table, 0, val); 45 if (ret < 0) 46 goto get_parent_err; 47 48 return ret; 49 50 get_parent_err: 51 pr_err("%s: failed to get parent (%pe)\n", 52 clk_hw_get_name(hw), ERR_PTR(ret)); 53 54 /* return some realistic non negative value. Potentially we could 55 * give index to some dummy error parent. 56 */ 57 return 0; 58 } 59 60 static int imx_clk_gpr_mux_set_parent(struct clk_hw *hw, u8 index) 61 { 62 struct imx_clk_gpr *priv = to_imx_clk_gpr(hw); 63 unsigned int val = clk_mux_index_to_val(priv->mux_table, 0, index); 64 65 return regmap_update_bits(priv->regmap, priv->reg, priv->mask, val); 66 } 67 68 static int imx_clk_gpr_mux_determine_rate(struct clk_hw *hw, 69 struct clk_rate_request *req) 70 { 71 return clk_mux_determine_rate_flags(hw, req, 0); 72 } 73 74 static const struct clk_ops imx_clk_gpr_mux_ops = { 75 .get_parent = imx_clk_gpr_mux_get_parent, 76 .set_parent = imx_clk_gpr_mux_set_parent, 77 .determine_rate = imx_clk_gpr_mux_determine_rate, 78 }; 79 80 struct clk_hw *imx_clk_gpr_mux(const char *name, const char *compatible, 81 u32 reg, const char **parent_names, 82 u8 num_parents, const u32 *mux_table, u32 mask) 83 { 84 struct clk_init_data init = { }; 85 struct imx_clk_gpr *priv; 86 struct regmap *regmap; 87 struct clk_hw *hw; 88 int ret; 89 90 regmap = syscon_regmap_lookup_by_compatible(compatible); 91 if (IS_ERR(regmap)) { 92 pr_err("failed to find %s regmap\n", compatible); 93 return ERR_CAST(regmap); 94 } 95 96 priv = kzalloc(sizeof(*priv), GFP_KERNEL); 97 if (!priv) 98 return ERR_PTR(-ENOMEM); 99 100 init.name = name; 101 init.ops = &imx_clk_gpr_mux_ops; 102 init.parent_names = parent_names; 103 init.num_parents = num_parents; 104 init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE; 105 106 priv->hw.init = &init; 107 priv->regmap = regmap; 108 priv->mux_table = mux_table; 109 priv->reg = reg; 110 priv->mask = mask; 111 112 hw = &priv->hw; 113 ret = clk_hw_register(NULL, &priv->hw); 114 if (ret) { 115 kfree(priv); 116 hw = ERR_PTR(ret); 117 } 118 119 return hw; 120 } 121