1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * phy-can-transceiver.c - phy driver for CAN transceivers 4 * 5 * Copyright (C) 2021 Texas Instruments Incorporated - https://www.ti.com 6 * 7 */ 8 #include <linux/of.h> 9 #include <linux/phy/phy.h> 10 #include <linux/platform_device.h> 11 #include <linux/module.h> 12 #include <linux/gpio.h> 13 #include <linux/gpio/consumer.h> 14 #include <linux/mux/consumer.h> 15 16 struct can_transceiver_data { 17 u32 flags; 18 #define CAN_TRANSCEIVER_STB_PRESENT BIT(0) 19 #define CAN_TRANSCEIVER_EN_PRESENT BIT(1) 20 #define CAN_TRANSCEIVER_DUAL_CH BIT(2) 21 #define CAN_TRANSCEIVER_SILENT_PRESENT BIT(3) 22 }; 23 24 struct can_transceiver_phy { 25 struct phy *generic_phy; 26 struct gpio_desc *silent_gpio; 27 struct gpio_desc *standby_gpio; 28 struct gpio_desc *enable_gpio; 29 struct can_transceiver_priv *priv; 30 }; 31 32 struct can_transceiver_priv { 33 struct mux_state *mux_state; 34 int num_ch; 35 struct can_transceiver_phy can_transceiver_phy[] __counted_by(num_ch); 36 }; 37 38 /* Power on function */ 39 static int can_transceiver_phy_power_on(struct phy *phy) 40 { 41 struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); 42 struct can_transceiver_priv *priv = can_transceiver_phy->priv; 43 int ret; 44 45 if (priv->mux_state) { 46 ret = mux_state_select(priv->mux_state); 47 if (ret) { 48 dev_err(&phy->dev, "Failed to select CAN mux: %d\n", ret); 49 return ret; 50 } 51 } 52 gpiod_set_value_cansleep(can_transceiver_phy->silent_gpio, 0); 53 gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 0); 54 gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 1); 55 56 return 0; 57 } 58 59 /* Power off function */ 60 static int can_transceiver_phy_power_off(struct phy *phy) 61 { 62 struct can_transceiver_phy *can_transceiver_phy = phy_get_drvdata(phy); 63 struct can_transceiver_priv *priv = can_transceiver_phy->priv; 64 65 gpiod_set_value_cansleep(can_transceiver_phy->silent_gpio, 1); 66 gpiod_set_value_cansleep(can_transceiver_phy->standby_gpio, 1); 67 gpiod_set_value_cansleep(can_transceiver_phy->enable_gpio, 0); 68 if (priv->mux_state) 69 mux_state_deselect(priv->mux_state); 70 71 return 0; 72 } 73 74 static const struct phy_ops can_transceiver_phy_ops = { 75 .power_on = can_transceiver_phy_power_on, 76 .power_off = can_transceiver_phy_power_off, 77 .owner = THIS_MODULE, 78 }; 79 80 static const struct can_transceiver_data tcan1042_drvdata = { 81 .flags = CAN_TRANSCEIVER_STB_PRESENT, 82 }; 83 84 static const struct can_transceiver_data tcan1043_drvdata = { 85 .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_EN_PRESENT, 86 }; 87 88 static const struct can_transceiver_data tja1048_drvdata = { 89 .flags = CAN_TRANSCEIVER_STB_PRESENT | CAN_TRANSCEIVER_DUAL_CH, 90 }; 91 92 static const struct can_transceiver_data tja1051_drvdata = { 93 .flags = CAN_TRANSCEIVER_SILENT_PRESENT | CAN_TRANSCEIVER_EN_PRESENT, 94 }; 95 96 static const struct can_transceiver_data tja1057_drvdata = { 97 .flags = CAN_TRANSCEIVER_SILENT_PRESENT, 98 }; 99 100 static const struct of_device_id can_transceiver_phy_ids[] = { 101 { 102 .compatible = "ti,tcan1042", 103 .data = &tcan1042_drvdata 104 }, 105 { 106 .compatible = "ti,tcan1043", 107 .data = &tcan1043_drvdata 108 }, 109 { 110 .compatible = "nxp,tja1048", 111 .data = &tja1048_drvdata 112 }, 113 { 114 .compatible = "nxp,tja1051", 115 .data = &tja1051_drvdata 116 }, 117 { 118 .compatible = "nxp,tja1057", 119 .data = &tja1057_drvdata 120 }, 121 { 122 .compatible = "nxp,tjr1443", 123 .data = &tcan1043_drvdata 124 }, 125 { } 126 }; 127 MODULE_DEVICE_TABLE(of, can_transceiver_phy_ids); 128 129 /* Temporary wrapper until the multiplexer subsystem supports optional muxes */ 130 static inline struct mux_state * 131 devm_mux_state_get_optional(struct device *dev, const char *mux_name) 132 { 133 if (!of_property_present(dev->of_node, "mux-states")) 134 return NULL; 135 136 return devm_mux_state_get(dev, mux_name); 137 } 138 139 static struct phy *can_transceiver_phy_xlate(struct device *dev, 140 const struct of_phandle_args *args) 141 { 142 struct can_transceiver_priv *priv = dev_get_drvdata(dev); 143 u32 idx; 144 145 if (priv->num_ch == 1) 146 return priv->can_transceiver_phy[0].generic_phy; 147 148 if (args->args_count != 1) 149 return ERR_PTR(-EINVAL); 150 151 idx = args->args[0]; 152 if (idx >= priv->num_ch) 153 return ERR_PTR(-EINVAL); 154 155 return priv->can_transceiver_phy[idx].generic_phy; 156 } 157 158 static int can_transceiver_phy_probe(struct platform_device *pdev) 159 { 160 struct phy_provider *phy_provider; 161 struct device *dev = &pdev->dev; 162 struct can_transceiver_phy *can_transceiver_phy; 163 struct can_transceiver_priv *priv; 164 const struct can_transceiver_data *drvdata; 165 const struct of_device_id *match; 166 struct phy *phy; 167 struct gpio_desc *silent_gpio; 168 struct gpio_desc *standby_gpio; 169 struct gpio_desc *enable_gpio; 170 struct mux_state *mux_state; 171 u32 max_bitrate = 0; 172 int err, i, num_ch = 1; 173 174 match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node); 175 drvdata = match->data; 176 if (drvdata->flags & CAN_TRANSCEIVER_DUAL_CH) 177 num_ch = 2; 178 179 priv = devm_kzalloc(dev, struct_size(priv, can_transceiver_phy, num_ch), GFP_KERNEL); 180 if (!priv) 181 return -ENOMEM; 182 183 priv->num_ch = num_ch; 184 platform_set_drvdata(pdev, priv); 185 186 mux_state = devm_mux_state_get_optional(dev, NULL); 187 if (IS_ERR(mux_state)) 188 return PTR_ERR(mux_state); 189 190 priv->mux_state = mux_state; 191 192 err = device_property_read_u32(dev, "max-bitrate", &max_bitrate); 193 if ((err != -EINVAL) && !max_bitrate) 194 dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n"); 195 196 for (i = 0; i < num_ch; i++) { 197 can_transceiver_phy = &priv->can_transceiver_phy[i]; 198 can_transceiver_phy->priv = priv; 199 200 phy = devm_phy_create(dev, dev->of_node, &can_transceiver_phy_ops); 201 if (IS_ERR(phy)) { 202 dev_err(dev, "failed to create can transceiver phy\n"); 203 return PTR_ERR(phy); 204 } 205 206 phy->attrs.max_link_rate = max_bitrate; 207 208 can_transceiver_phy->generic_phy = phy; 209 can_transceiver_phy->priv = priv; 210 211 if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) { 212 standby_gpio = devm_gpiod_get_index_optional(dev, "standby", i, 213 GPIOD_OUT_HIGH); 214 if (IS_ERR(standby_gpio)) 215 return PTR_ERR(standby_gpio); 216 can_transceiver_phy->standby_gpio = standby_gpio; 217 } 218 219 if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) { 220 enable_gpio = devm_gpiod_get_index_optional(dev, "enable", i, 221 GPIOD_OUT_LOW); 222 if (IS_ERR(enable_gpio)) 223 return PTR_ERR(enable_gpio); 224 can_transceiver_phy->enable_gpio = enable_gpio; 225 } 226 227 if (drvdata->flags & CAN_TRANSCEIVER_SILENT_PRESENT) { 228 silent_gpio = devm_gpiod_get_index_optional(dev, "silent", i, 229 GPIOD_OUT_LOW); 230 if (IS_ERR(silent_gpio)) 231 return PTR_ERR(silent_gpio); 232 can_transceiver_phy->silent_gpio = silent_gpio; 233 } 234 235 phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy); 236 237 } 238 239 phy_provider = devm_of_phy_provider_register(dev, can_transceiver_phy_xlate); 240 241 return PTR_ERR_OR_ZERO(phy_provider); 242 } 243 244 static struct platform_driver can_transceiver_phy_driver = { 245 .probe = can_transceiver_phy_probe, 246 .driver = { 247 .name = "can-transceiver-phy", 248 .of_match_table = can_transceiver_phy_ids, 249 }, 250 }; 251 252 module_platform_driver(can_transceiver_phy_driver); 253 254 MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>"); 255 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>"); 256 MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver"); 257 MODULE_LICENSE("GPL v2"); 258