1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * (C) Copyright 2017 4 * Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc 5 */ 6 7 #include <common.h> 8 #include <dm.h> 9 #include <board.h> 10 #include <i2c.h> 11 #include <asm/gpio.h> 12 13 #include "gazerbeam.h" 14 15 /* Sequence number of I2C bus that holds the GPIO expanders */ 16 static const int I2C_BUS_SEQ_NO = 1; 17 18 /* I2C address of SC/MC2 expander */ 19 static const int MC2_EXPANDER_ADDR = 0x20; 20 /* I2C address of MC4 expander */ 21 static const int MC4_EXPANDER_ADDR = 0x22; 22 23 /* Number of the GPIO to read the SC data from */ 24 static const int SC_GPIO_NO; 25 /* Number of the GPIO to read the CON data from */ 26 static const int CON_GPIO_NO = 1; 27 28 /** 29 * struct board_gazerbeam_priv - Private data structure for the gazerbeam board 30 * driver. 31 * @reset_gpios: GPIOs for the board's reset GPIOs. 32 * @var_gpios: GPIOs for the board's hardware variant GPIOs 33 * @ver_gpios: GPIOs for the board's hardware version GPIOs 34 * @variant: Container for the board's hardware variant (CON/CPU) 35 * @multichannel: Container for the board's multichannel variant (MC4/MC2/SC) 36 * @hwversion: Container for the board's hardware version 37 */ 38 struct board_gazerbeam_priv { 39 struct gpio_desc reset_gpios[2]; 40 struct gpio_desc var_gpios[2]; 41 struct gpio_desc ver_gpios[4]; 42 int variant; 43 int multichannel; 44 int hwversion; 45 }; 46 47 /** 48 * _read_board_variant_data() - Read variant information from the hardware. 49 * @dev: The board device for which to determine the multichannel and device 50 * type information. 51 * 52 * The data read from the board's hardware (mostly hard-wired GPIOs) is stored 53 * in the private data structure of the driver to be used by other driver 54 * methods. 55 * 56 * Return: 0 if OK, -ve on error. 57 */ 58 static int _read_board_variant_data(struct udevice *dev) 59 { 60 struct board_gazerbeam_priv *priv = dev_get_priv(dev); 61 struct udevice *i2c_bus; 62 struct udevice *dummy; 63 char *listname; 64 int mc4, mc2, sc, con; 65 int gpio_num; 66 int res; 67 68 res = uclass_get_device_by_seq(UCLASS_I2C, I2C_BUS_SEQ_NO, &i2c_bus); 69 if (res) { 70 debug("%s: Could not get I2C bus %d (err = %d)\n", 71 dev->name, I2C_BUS_SEQ_NO, res); 72 return res; 73 } 74 75 if (!i2c_bus) { 76 debug("%s: Could not get I2C bus %d\n", 77 dev->name, I2C_BUS_SEQ_NO); 78 return -EIO; 79 } 80 81 mc2 = !dm_i2c_probe(i2c_bus, MC2_EXPANDER_ADDR, 0, &dummy); 82 mc4 = !dm_i2c_probe(i2c_bus, MC4_EXPANDER_ADDR, 0, &dummy); 83 84 if (mc2 && mc4) { 85 debug("%s: Board hardware configuration inconsistent.\n", 86 dev->name); 87 return -EINVAL; 88 } 89 90 listname = mc2 ? "var-gpios-mc2" : "var-gpios-mc4"; 91 92 gpio_num = gpio_request_list_by_name(dev, listname, priv->var_gpios, 93 ARRAY_SIZE(priv->var_gpios), 94 GPIOD_IS_IN); 95 if (gpio_num < 0) { 96 debug("%s: Requesting gpio list %s failed (err = %d).\n", 97 dev->name, listname, gpio_num); 98 return gpio_num; 99 } 100 101 sc = dm_gpio_get_value(&priv->var_gpios[SC_GPIO_NO]); 102 if (sc < 0) { 103 debug("%s: Error while reading 'sc' GPIO (err = %d)", 104 dev->name, sc); 105 return sc; 106 } 107 108 con = dm_gpio_get_value(&priv->var_gpios[CON_GPIO_NO]); 109 if (con < 0) { 110 debug("%s: Error while reading 'con' GPIO (err = %d)", 111 dev->name, con); 112 return con; 113 } 114 115 if ((sc && mc2) || (sc && mc4) || (!sc && !mc2 && !mc4)) { 116 debug("%s: Board hardware configuration inconsistent.\n", 117 dev->name); 118 return -EINVAL; 119 } 120 121 priv->variant = con ? VAR_CON : VAR_CPU; 122 123 priv->multichannel = mc4 ? 4 : (mc2 ? 2 : (sc ? 1 : 0)); 124 125 return 0; 126 } 127 128 /** 129 * _read_hwversion() - Read the hardware version from the board. 130 * @dev: The board device for which to read the hardware version. 131 * 132 * The hardware version read from the board (from hard-wired GPIOs) is stored 133 * in the private data structure of the driver to be used by other driver 134 * methods. 135 * 136 * Return: 0 if OK, -ve on error. 137 */ 138 static int _read_hwversion(struct udevice *dev) 139 { 140 struct board_gazerbeam_priv *priv = dev_get_priv(dev); 141 int res; 142 143 res = gpio_request_list_by_name(dev, "ver-gpios", priv->ver_gpios, 144 ARRAY_SIZE(priv->ver_gpios), 145 GPIOD_IS_IN); 146 if (res < 0) { 147 debug("%s: Error getting GPIO list 'ver-gpios' (err = %d)\n", 148 dev->name, res); 149 return -ENODEV; 150 } 151 152 res = dm_gpio_get_values_as_int(priv->ver_gpios, 153 ARRAY_SIZE(priv->ver_gpios)); 154 if (res < 0) { 155 debug("%s: Error reading HW version from expander (err = %d)\n", 156 dev->name, res); 157 return res; 158 } 159 160 priv->hwversion = res; 161 162 res = gpio_free_list(dev, priv->ver_gpios, ARRAY_SIZE(priv->ver_gpios)); 163 if (res < 0) { 164 debug("%s: Error freeing HW version GPIO list (err = %d)\n", 165 dev->name, res); 166 return res; 167 } 168 169 return 0; 170 } 171 172 static int board_gazerbeam_detect(struct udevice *dev) 173 { 174 int res; 175 176 res = _read_board_variant_data(dev); 177 if (res) { 178 debug("%s: Error reading multichannel variant (err = %d)\n", 179 dev->name, res); 180 return res; 181 } 182 183 res = _read_hwversion(dev); 184 if (res) { 185 debug("%s: Error reading hardware version (err = %d)\n", 186 dev->name, res); 187 return res; 188 } 189 190 return 0; 191 } 192 193 static int board_gazerbeam_get_int(struct udevice *dev, int id, int *val) 194 { 195 struct board_gazerbeam_priv *priv = dev_get_priv(dev); 196 197 switch (id) { 198 case BOARD_MULTICHANNEL: 199 *val = priv->multichannel; 200 break; 201 case BOARD_VARIANT: 202 *val = priv->variant; 203 break; 204 case BOARD_HWVERSION: 205 *val = priv->hwversion; 206 break; 207 default: 208 debug("%s: Integer value %d unknown\n", dev->name, id); 209 return -EINVAL; 210 } 211 212 return 0; 213 } 214 215 static const struct udevice_id board_gazerbeam_ids[] = { 216 { .compatible = "gdsys,board_gazerbeam" }, 217 { /* sentinel */ } 218 }; 219 220 static const struct board_ops board_gazerbeam_ops = { 221 .detect = board_gazerbeam_detect, 222 .get_int = board_gazerbeam_get_int, 223 }; 224 225 static int board_gazerbeam_probe(struct udevice *dev) 226 { 227 struct board_gazerbeam_priv *priv = dev_get_priv(dev); 228 int gpio_num, i; 229 230 gpio_num = gpio_request_list_by_name(dev, "reset-gpios", 231 priv->reset_gpios, 232 ARRAY_SIZE(priv->reset_gpios), 233 GPIOD_IS_OUT); 234 235 if (gpio_num < 0) { 236 debug("%s: Error getting GPIO list 'reset-gpios' (err = %d)\n", 237 dev->name, gpio_num); 238 return gpio_num; 239 } 240 241 /* Set startup-finished GPIOs */ 242 for (i = 0; i < ARRAY_SIZE(priv->reset_gpios); i++) { 243 int res = dm_gpio_set_value(&priv->reset_gpios[i], 0); 244 245 if (res) { 246 debug("%s: Error while setting GPIO %d (err = %d)\n", 247 dev->name, i, res); 248 return res; 249 } 250 } 251 252 return 0; 253 } 254 255 U_BOOT_DRIVER(board_gazerbeam) = { 256 .name = "board_gazerbeam", 257 .id = UCLASS_BOARD, 258 .of_match = board_gazerbeam_ids, 259 .ops = &board_gazerbeam_ops, 260 .priv_auto_alloc_size = sizeof(struct board_gazerbeam_priv), 261 .probe = board_gazerbeam_probe, 262 }; 263