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 static struct phy *can_transceiver_phy_xlate(struct device *dev, 130 const struct of_phandle_args *args) 131 { 132 struct can_transceiver_priv *priv = dev_get_drvdata(dev); 133 u32 idx; 134 135 if (priv->num_ch == 1) 136 return priv->can_transceiver_phy[0].generic_phy; 137 138 if (args->args_count != 1) 139 return ERR_PTR(-EINVAL); 140 141 idx = args->args[0]; 142 if (idx >= priv->num_ch) 143 return ERR_PTR(-EINVAL); 144 145 return priv->can_transceiver_phy[idx].generic_phy; 146 } 147 148 static int can_transceiver_phy_probe(struct platform_device *pdev) 149 { 150 struct phy_provider *phy_provider; 151 struct device *dev = &pdev->dev; 152 struct can_transceiver_phy *can_transceiver_phy; 153 struct can_transceiver_priv *priv; 154 const struct can_transceiver_data *drvdata; 155 const struct of_device_id *match; 156 struct phy *phy; 157 struct gpio_desc *silent_gpio; 158 struct gpio_desc *standby_gpio; 159 struct gpio_desc *enable_gpio; 160 struct mux_state *mux_state; 161 u32 max_bitrate = 0; 162 int err, i, num_ch = 1; 163 164 match = of_match_node(can_transceiver_phy_ids, pdev->dev.of_node); 165 drvdata = match->data; 166 if (drvdata->flags & CAN_TRANSCEIVER_DUAL_CH) 167 num_ch = 2; 168 169 priv = devm_kzalloc(dev, struct_size(priv, can_transceiver_phy, num_ch), GFP_KERNEL); 170 if (!priv) 171 return -ENOMEM; 172 173 priv->num_ch = num_ch; 174 platform_set_drvdata(pdev, priv); 175 176 mux_state = devm_mux_state_get_optional(dev, NULL); 177 if (IS_ERR(mux_state)) 178 return PTR_ERR(mux_state); 179 180 priv->mux_state = mux_state; 181 182 err = device_property_read_u32(dev, "max-bitrate", &max_bitrate); 183 if ((err != -EINVAL) && !max_bitrate) 184 dev_warn(dev, "Invalid value for transceiver max bitrate. Ignoring bitrate limit\n"); 185 186 for (i = 0; i < num_ch; i++) { 187 can_transceiver_phy = &priv->can_transceiver_phy[i]; 188 can_transceiver_phy->priv = priv; 189 190 phy = devm_phy_create(dev, dev->of_node, &can_transceiver_phy_ops); 191 if (IS_ERR(phy)) { 192 dev_err(dev, "failed to create can transceiver phy\n"); 193 return PTR_ERR(phy); 194 } 195 196 phy->attrs.max_link_rate = max_bitrate; 197 198 can_transceiver_phy->generic_phy = phy; 199 can_transceiver_phy->priv = priv; 200 201 if (drvdata->flags & CAN_TRANSCEIVER_STB_PRESENT) { 202 standby_gpio = devm_gpiod_get_index_optional(dev, "standby", i, 203 GPIOD_OUT_HIGH); 204 if (IS_ERR(standby_gpio)) 205 return PTR_ERR(standby_gpio); 206 can_transceiver_phy->standby_gpio = standby_gpio; 207 } 208 209 if (drvdata->flags & CAN_TRANSCEIVER_EN_PRESENT) { 210 enable_gpio = devm_gpiod_get_index_optional(dev, "enable", i, 211 GPIOD_OUT_LOW); 212 if (IS_ERR(enable_gpio)) 213 return PTR_ERR(enable_gpio); 214 can_transceiver_phy->enable_gpio = enable_gpio; 215 } 216 217 if (drvdata->flags & CAN_TRANSCEIVER_SILENT_PRESENT) { 218 silent_gpio = devm_gpiod_get_index_optional(dev, "silent", i, 219 GPIOD_OUT_LOW); 220 if (IS_ERR(silent_gpio)) 221 return PTR_ERR(silent_gpio); 222 can_transceiver_phy->silent_gpio = silent_gpio; 223 } 224 225 phy_set_drvdata(can_transceiver_phy->generic_phy, can_transceiver_phy); 226 227 } 228 229 phy_provider = devm_of_phy_provider_register(dev, can_transceiver_phy_xlate); 230 231 return PTR_ERR_OR_ZERO(phy_provider); 232 } 233 234 static struct platform_driver can_transceiver_phy_driver = { 235 .probe = can_transceiver_phy_probe, 236 .driver = { 237 .name = "can-transceiver-phy", 238 .of_match_table = can_transceiver_phy_ids, 239 }, 240 }; 241 242 module_platform_driver(can_transceiver_phy_driver); 243 244 MODULE_AUTHOR("Faiz Abbas <faiz_abbas@ti.com>"); 245 MODULE_AUTHOR("Aswath Govindraju <a-govindraju@ti.com>"); 246 MODULE_DESCRIPTION("CAN TRANSCEIVER PHY driver"); 247 MODULE_LICENSE("GPL v2"); 248