1 /* 2 * NVIDIA Tegra20 GPIO handling. 3 * (C) Copyright 2010-2012 4 * NVIDIA Corporation <www.nvidia.com> 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 /* 10 * Based on (mostly copied from) kw_gpio.c based Linux 2.6 kernel driver. 11 * Tom Warren (twarren@nvidia.com) 12 */ 13 14 #include <common.h> 15 #include <dm.h> 16 #include <malloc.h> 17 #include <errno.h> 18 #include <fdtdec.h> 19 #include <asm/io.h> 20 #include <asm/bitops.h> 21 #include <asm/arch/tegra.h> 22 #include <asm/gpio.h> 23 #include <dm/device-internal.h> 24 #include <dt-bindings/gpio/gpio.h> 25 26 DECLARE_GLOBAL_DATA_PTR; 27 28 enum { 29 TEGRA_CMD_INFO, 30 TEGRA_CMD_PORT, 31 TEGRA_CMD_OUTPUT, 32 TEGRA_CMD_INPUT, 33 }; 34 35 struct tegra_gpio_platdata { 36 struct gpio_ctlr_bank *bank; 37 const char *port_name; /* Name of port, e.g. "B" */ 38 int base_gpio; /* Port number for this port (0, 1,.., n-1) */ 39 }; 40 41 /* Information about each port at run-time */ 42 struct tegra_port_info { 43 struct gpio_ctlr_bank *bank; 44 int base_gpio; /* Port number for this port (0, 1,.., n-1) */ 45 }; 46 47 /* Return config of pin 'gpio' as GPIO (1) or SFPIO (0) */ 48 static int get_config(unsigned gpio) 49 { 50 struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE; 51 struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)]; 52 u32 u; 53 int type; 54 55 u = readl(&bank->gpio_config[GPIO_PORT(gpio)]); 56 type = (u >> GPIO_BIT(gpio)) & 1; 57 58 debug("get_config: port = %d, bit = %d is %s\n", 59 GPIO_FULLPORT(gpio), GPIO_BIT(gpio), type ? "GPIO" : "SFPIO"); 60 61 return type; 62 } 63 64 /* Config pin 'gpio' as GPIO or SFPIO, based on 'type' */ 65 static void set_config(unsigned gpio, int type) 66 { 67 struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE; 68 struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)]; 69 u32 u; 70 71 debug("set_config: port = %d, bit = %d, %s\n", 72 GPIO_FULLPORT(gpio), GPIO_BIT(gpio), type ? "GPIO" : "SFPIO"); 73 74 u = readl(&bank->gpio_config[GPIO_PORT(gpio)]); 75 if (type) /* GPIO */ 76 u |= 1 << GPIO_BIT(gpio); 77 else 78 u &= ~(1 << GPIO_BIT(gpio)); 79 writel(u, &bank->gpio_config[GPIO_PORT(gpio)]); 80 } 81 82 /* Return GPIO pin 'gpio' direction - 0 = input or 1 = output */ 83 static int get_direction(unsigned gpio) 84 { 85 struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE; 86 struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)]; 87 u32 u; 88 int dir; 89 90 u = readl(&bank->gpio_dir_out[GPIO_PORT(gpio)]); 91 dir = (u >> GPIO_BIT(gpio)) & 1; 92 93 debug("get_direction: port = %d, bit = %d, %s\n", 94 GPIO_FULLPORT(gpio), GPIO_BIT(gpio), dir ? "OUT" : "IN"); 95 96 return dir; 97 } 98 99 /* Config GPIO pin 'gpio' as input or output (OE) as per 'output' */ 100 static void set_direction(unsigned gpio, int output) 101 { 102 struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE; 103 struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)]; 104 u32 u; 105 106 debug("set_direction: port = %d, bit = %d, %s\n", 107 GPIO_FULLPORT(gpio), GPIO_BIT(gpio), output ? "OUT" : "IN"); 108 109 u = readl(&bank->gpio_dir_out[GPIO_PORT(gpio)]); 110 if (output) 111 u |= 1 << GPIO_BIT(gpio); 112 else 113 u &= ~(1 << GPIO_BIT(gpio)); 114 writel(u, &bank->gpio_dir_out[GPIO_PORT(gpio)]); 115 } 116 117 /* set GPIO pin 'gpio' output bit as 0 or 1 as per 'high' */ 118 static void set_level(unsigned gpio, int high) 119 { 120 struct gpio_ctlr *ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE; 121 struct gpio_ctlr_bank *bank = &ctlr->gpio_bank[GPIO_BANK(gpio)]; 122 u32 u; 123 124 debug("set_level: port = %d, bit %d == %d\n", 125 GPIO_FULLPORT(gpio), GPIO_BIT(gpio), high); 126 127 u = readl(&bank->gpio_out[GPIO_PORT(gpio)]); 128 if (high) 129 u |= 1 << GPIO_BIT(gpio); 130 else 131 u &= ~(1 << GPIO_BIT(gpio)); 132 writel(u, &bank->gpio_out[GPIO_PORT(gpio)]); 133 } 134 135 /* 136 * Generic_GPIO primitives. 137 */ 138 139 /* set GPIO pin 'gpio' as an input */ 140 static int tegra_gpio_direction_input(struct udevice *dev, unsigned offset) 141 { 142 struct tegra_port_info *state = dev_get_priv(dev); 143 144 /* Configure GPIO direction as input. */ 145 set_direction(state->base_gpio + offset, 0); 146 147 /* Enable the pin as a GPIO */ 148 set_config(state->base_gpio + offset, 1); 149 150 return 0; 151 } 152 153 /* set GPIO pin 'gpio' as an output, with polarity 'value' */ 154 static int tegra_gpio_direction_output(struct udevice *dev, unsigned offset, 155 int value) 156 { 157 struct tegra_port_info *state = dev_get_priv(dev); 158 int gpio = state->base_gpio + offset; 159 160 /* Configure GPIO output value. */ 161 set_level(gpio, value); 162 163 /* Configure GPIO direction as output. */ 164 set_direction(gpio, 1); 165 166 /* Enable the pin as a GPIO */ 167 set_config(state->base_gpio + offset, 1); 168 169 return 0; 170 } 171 172 /* read GPIO IN value of pin 'gpio' */ 173 static int tegra_gpio_get_value(struct udevice *dev, unsigned offset) 174 { 175 struct tegra_port_info *state = dev_get_priv(dev); 176 int gpio = state->base_gpio + offset; 177 int val; 178 179 debug("%s: pin = %d (port %d:bit %d)\n", __func__, 180 gpio, GPIO_FULLPORT(gpio), GPIO_BIT(gpio)); 181 182 val = readl(&state->bank->gpio_in[GPIO_PORT(gpio)]); 183 184 return (val >> GPIO_BIT(gpio)) & 1; 185 } 186 187 /* write GPIO OUT value to pin 'gpio' */ 188 static int tegra_gpio_set_value(struct udevice *dev, unsigned offset, int value) 189 { 190 struct tegra_port_info *state = dev_get_priv(dev); 191 int gpio = state->base_gpio + offset; 192 193 debug("gpio_set_value: pin = %d (port %d:bit %d), value = %d\n", 194 gpio, GPIO_FULLPORT(gpio), GPIO_BIT(gpio), value); 195 196 /* Configure GPIO output value. */ 197 set_level(gpio, value); 198 199 return 0; 200 } 201 202 void gpio_config_table(const struct tegra_gpio_config *config, int len) 203 { 204 int i; 205 206 for (i = 0; i < len; i++) { 207 switch (config[i].init) { 208 case TEGRA_GPIO_INIT_IN: 209 set_direction(config[i].gpio, 0); 210 break; 211 case TEGRA_GPIO_INIT_OUT0: 212 set_level(config[i].gpio, 0); 213 set_direction(config[i].gpio, 1); 214 break; 215 case TEGRA_GPIO_INIT_OUT1: 216 set_level(config[i].gpio, 1); 217 set_direction(config[i].gpio, 1); 218 break; 219 } 220 set_config(config[i].gpio, 1); 221 } 222 } 223 224 static int tegra_gpio_get_function(struct udevice *dev, unsigned offset) 225 { 226 struct tegra_port_info *state = dev_get_priv(dev); 227 int gpio = state->base_gpio + offset; 228 229 if (!get_config(gpio)) 230 return GPIOF_FUNC; 231 else if (get_direction(gpio)) 232 return GPIOF_OUTPUT; 233 else 234 return GPIOF_INPUT; 235 } 236 237 static int tegra_gpio_xlate(struct udevice *dev, struct gpio_desc *desc, 238 struct fdtdec_phandle_args *args) 239 { 240 int gpio, port, ret; 241 242 gpio = args->args[0]; 243 port = gpio / TEGRA_GPIOS_PER_PORT; 244 ret = device_get_child(dev, port, &desc->dev); 245 if (ret) 246 return ret; 247 desc->offset = gpio % TEGRA_GPIOS_PER_PORT; 248 desc->flags = args->args[1] & GPIO_ACTIVE_LOW ? GPIOD_ACTIVE_LOW : 0; 249 250 return 0; 251 } 252 253 static const struct dm_gpio_ops gpio_tegra_ops = { 254 .direction_input = tegra_gpio_direction_input, 255 .direction_output = tegra_gpio_direction_output, 256 .get_value = tegra_gpio_get_value, 257 .set_value = tegra_gpio_set_value, 258 .get_function = tegra_gpio_get_function, 259 .xlate = tegra_gpio_xlate, 260 }; 261 262 /** 263 * Returns the name of a GPIO port 264 * 265 * GPIOs are named A, B, C, ..., Z, AA, BB, CC, ... 266 * 267 * @base_port: Base port number (0, 1..n-1) 268 * @return allocated string containing the name 269 */ 270 static char *gpio_port_name(int base_port) 271 { 272 char *name, *s; 273 274 name = malloc(3); 275 if (name) { 276 s = name; 277 *s++ = 'A' + (base_port % 26); 278 if (base_port >= 26) 279 *s++ = *name; 280 *s = '\0'; 281 } 282 283 return name; 284 } 285 286 static const struct udevice_id tegra_gpio_ids[] = { 287 { .compatible = "nvidia,tegra30-gpio" }, 288 { .compatible = "nvidia,tegra20-gpio" }, 289 { } 290 }; 291 292 static int gpio_tegra_probe(struct udevice *dev) 293 { 294 struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev); 295 struct tegra_port_info *priv = dev->priv; 296 struct tegra_gpio_platdata *plat = dev->platdata; 297 298 /* Only child devices have ports */ 299 if (!plat) 300 return 0; 301 302 priv->bank = plat->bank; 303 priv->base_gpio = plat->base_gpio; 304 305 uc_priv->gpio_count = TEGRA_GPIOS_PER_PORT; 306 uc_priv->bank_name = plat->port_name; 307 308 return 0; 309 } 310 311 /** 312 * We have a top-level GPIO device with no actual GPIOs. It has a child 313 * device for each Tegra port. 314 */ 315 static int gpio_tegra_bind(struct udevice *parent) 316 { 317 struct tegra_gpio_platdata *plat = parent->platdata; 318 struct gpio_ctlr *ctlr; 319 int bank_count; 320 int bank; 321 int ret; 322 323 /* If this is a child device, there is nothing to do here */ 324 if (plat) 325 return 0; 326 327 /* TODO(sjg@chromium.org): Remove once SPL supports device tree */ 328 #ifdef CONFIG_SPL_BUILD 329 ctlr = (struct gpio_ctlr *)NV_PA_GPIO_BASE; 330 bank_count = TEGRA_GPIO_BANKS; 331 #else 332 { 333 int len; 334 335 /* 336 * This driver does not make use of interrupts, other than to figure 337 * out the number of GPIO banks 338 */ 339 if (!fdt_getprop(gd->fdt_blob, parent->of_offset, "interrupts", &len)) 340 return -EINVAL; 341 bank_count = len / 3 / sizeof(u32); 342 ctlr = (struct gpio_ctlr *)dev_get_addr(parent); 343 } 344 #endif 345 for (bank = 0; bank < bank_count; bank++) { 346 int port; 347 348 for (port = 0; port < TEGRA_PORTS_PER_BANK; port++) { 349 struct tegra_gpio_platdata *plat; 350 struct udevice *dev; 351 int base_port; 352 353 plat = calloc(1, sizeof(*plat)); 354 if (!plat) 355 return -ENOMEM; 356 plat->bank = &ctlr->gpio_bank[bank]; 357 base_port = bank * TEGRA_PORTS_PER_BANK + port; 358 plat->base_gpio = TEGRA_GPIOS_PER_PORT * base_port; 359 plat->port_name = gpio_port_name(base_port); 360 361 ret = device_bind(parent, parent->driver, 362 plat->port_name, plat, -1, &dev); 363 if (ret) 364 return ret; 365 dev->of_offset = parent->of_offset; 366 } 367 } 368 369 return 0; 370 } 371 372 U_BOOT_DRIVER(gpio_tegra) = { 373 .name = "gpio_tegra", 374 .id = UCLASS_GPIO, 375 .of_match = tegra_gpio_ids, 376 .bind = gpio_tegra_bind, 377 .probe = gpio_tegra_probe, 378 .priv_auto_alloc_size = sizeof(struct tegra_port_info), 379 .ops = &gpio_tegra_ops, 380 .flags = DM_FLAG_PRE_RELOC, 381 }; 382