target/linux/brcm2708/patches-4.9/0198-bcm2835-gpio-exp-Driver-for-GPIO-expander-via-mailbo.patch

   1 From 2f8f62fbd42a55825da437faba4b6164f2e0bee9 Mon Sep 17 00:00:00 2001
   2 From: Dave Stevenson <dave.stevenson@raspberrypi.org>
   3 Date: Mon, 20 Feb 2017 17:01:21 +0000
   4 Subject: [PATCH] bcm2835-gpio-exp: Driver for GPIO expander via mailbox
   5  service
   6
   7 Pi3 and Compute Module 3 have a GPIO expander that the
   8 VPU communicates with.
   9 There is a mailbox service that now allows control of this
  10 expander, so add a kernel driver that can make use of it.
  11
  12 Pwr_led node added to device-tree for Pi3.
  13
  14 Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.org>
  15 ---
  16  arch/arm/boot/dts/bcm2710-rpi-3-b.dts      |  22 +++
  17  arch/arm/boot/dts/bcm2710-rpi-cm3.dts      |  10 +-
  18  arch/arm/configs/bcm2709_defconfig         |   1 +
  19  drivers/gpio/Kconfig                       |   7 +
  20  drivers/gpio/Makefile                      |   1 +
  21  drivers/gpio/gpio-bcm-exp.c                | 256 +++++++++++++++++++++++++++++
  22  include/soc/bcm2835/raspberrypi-firmware.h |   4 +
  23  7 files changed, 300 insertions(+), 1 deletion(-)
  24  create mode 100644 drivers/gpio/gpio-bcm-exp.c
  25
  26 --- a/arch/arm/boot/dts/bcm2710-rpi-3-b.dts
  27 +++ b/arch/arm/boot/dts/bcm2710-rpi-3-b.dts
  28 @@ -96,6 +96,14 @@
  29                 firmware = <&firmware>;
  30                 status = "okay";
  31         };
  32 +
  33 +       expgpio: expgpio {
  34 +               compatible = "brcm,bcm2835-expgpio";
  35 +               gpio-controller;
  36 +               #gpio-cells = <2>;
  37 +               firmware = <&firmware>;
  38 +               status = "okay";
  39 +       };
  40  };
  41
  42  &fb {
  43 @@ -163,6 +171,16 @@
  44                 linux,default-trigger = "mmc0";
  45                 gpios = <&virtgpio 0 0>;
  46         };
  47 +
  48 +       pwr_led: pwr {
  49 +               label = "led1";
  50 +               linux,default-trigger = "input";
  51 +               gpios = <&expgpio 7 GPIO_ACTIVE_LOW>;
  52 +       };
  53 +};
  54 +
  55 +&hdmi {
  56 +       hpd-gpios = <&expgpio 4 GPIO_ACTIVE_LOW>;
  57  };
  58
  59  &audio {
  60 @@ -193,6 +211,10 @@
  61                 act_led_activelow = <&act_led>,"gpios:8";
  62                 act_led_trigger = <&act_led>,"linux,default-trigger";
  63
  64 +               pwr_led_gpio = <&pwr_led>,"gpios:4";
  65 +               pwr_led_activelow = <&pwr_led>,"gpios:8";
  66 +               pwr_led_trigger = <&pwr_led>,"linux,default-trigger";
  67 +
  68                 audio = <&audio>,"status";
  69                 watchdog = <&watchdog>,"status";
  70                 random = <&random>,"status";
  71 --- a/arch/arm/boot/dts/bcm2710-rpi-cm3.dts
  72 +++ b/arch/arm/boot/dts/bcm2710-rpi-cm3.dts
  73 @@ -65,6 +65,14 @@
  74                 firmware = <&firmware>;
  75                 status = "okay";
  76         };
  77 +
  78 +       expgpio: expgpio {
  79 +               compatible = "brcm,bcm2835-expgpio";
  80 +               gpio-controller;
  81 +               #gpio-cells = <2>;
  82 +               firmware = <&firmware>;
  83 +               status = "okay";
  84 +       };
  85  };
  86
  87  &fb {
  88 @@ -123,7 +131,7 @@
  89  };
  90
  91  &hdmi {
  92 -       hpd-gpios = <&gpio 46 GPIO_ACTIVE_LOW>;
  93 +       hpd-gpios = <&expgpio 0 GPIO_ACTIVE_LOW>;
  94  };
  95
  96  &audio {
  97 --- a/arch/arm/configs/bcm2709_defconfig
  98 +++ b/arch/arm/configs/bcm2709_defconfig
  99 @@ -625,6 +625,7 @@ CONFIG_PPS=m
 100  CONFIG_PPS_CLIENT_LDISC=m
 101  CONFIG_PPS_CLIENT_GPIO=m
 102  CONFIG_GPIO_SYSFS=y
 103 +CONFIG_GPIO_BCM_EXP=y
 104  CONFIG_GPIO_BCM_VIRT=y
 105  CONFIG_GPIO_ARIZONA=m
 106  CONFIG_GPIO_STMPE=y
 107 --- a/drivers/gpio/Kconfig
 108 +++ b/drivers/gpio/Kconfig
 109 @@ -128,6 +128,13 @@ config GPIO_AXP209
 110         help
 111           Say yes to enable GPIO support for the AXP209 PMIC
 112
 113 +config GPIO_BCM_EXP
 114 +       bool "Broadcom Exp GPIO"
 115 +       depends on OF_GPIO && RASPBERRYPI_FIRMWARE && (ARCH_BCM2835 || COMPILE_TEST)
 116 +       help
 117 +         Turn on GPIO support for Broadcom chips using the firmware mailbox
 118 +         to communicate with VideoCore on BCM283x chips.
 119 +
 120  config GPIO_BCM_KONA
 121         bool "Broadcom Kona GPIO"
 122         depends on OF_GPIO && (ARCH_BCM_MOBILE || COMPILE_TEST)
 123 --- a/drivers/gpio/Makefile
 124 +++ b/drivers/gpio/Makefile
 125 @@ -30,6 +30,7 @@ obj-$(CONFIG_GPIO_ARIZONA)    += gpio-arizo
 126  obj-$(CONFIG_GPIO_ATH79)       += gpio-ath79.o
 127  obj-$(CONFIG_GPIO_ASPEED)      += gpio-aspeed.o
 128  obj-$(CONFIG_GPIO_AXP209)      += gpio-axp209.o
 129 +obj-$(CONFIG_GPIO_BCM_EXP)     += gpio-bcm-exp.o
 130  obj-$(CONFIG_GPIO_BCM_KONA)    += gpio-bcm-kona.o
 131  obj-$(CONFIG_GPIO_BCM_VIRT)    += gpio-bcm-virt.o
 132  obj-$(CONFIG_GPIO_BRCMSTB)     += gpio-brcmstb.o
 133 --- /dev/null
 134 +++ b/drivers/gpio/gpio-bcm-exp.c
 135 @@ -0,0 +1,256 @@
 136 +/*
 137 + *  Broadcom expander GPIO driver
 138 + *
 139 + *  Uses the firmware mailbox service to communicate with the
 140 + *  GPIO expander on the VPU.
 141 + *
 142 + *  Copyright (C) 2017 Raspberry Pi Trading Ltd.
 143 + *
 144 + *  Author: Dave Stevenson <dave.stevenson@raspberrypi.org>
 145 + *  Based on gpio-bcm-virt.c by Dom Cobley <popcornmix@gmail.com>
 146 + *
 147 + * This program is free software; you can redistribute it and/or modify
 148 + * it under the terms of the GNU General Public License as published by
 149 + * the Free Software Foundation; either version 2 of the License, or
 150 + * (at your option) any later version.
 151 + */
 152 +
 153 +#include <linux/err.h>
 154 +#include <linux/gpio.h>
 155 +#include <linux/module.h>
 156 +#include <linux/platform_device.h>
 157 +#include <linux/dma-mapping.h>
 158 +#include <soc/bcm2835/raspberrypi-firmware.h>
 159 +
 160 +#define MODULE_NAME "brcmexp-gpio"
 161 +#define NUM_GPIO 8
 162 +
 163 +struct brcmexp_gpio {
 164 +       struct gpio_chip gc;
 165 +       struct device *dev;
 166 +       struct rpi_firmware *fw;
 167 +};
 168 +
 169 +struct gpio_set_config {
 170 +       u32 gpio, direction, polarity, term_en, term_pull_up, state;
 171 +};
 172 +
 173 +struct gpio_get_config {
 174 +       u32 gpio, direction, polarity, term_en, term_pull_up;
 175 +};
 176 +
 177 +struct gpio_get_set_state {
 178 +       u32 gpio, state;
 179 +};
 180 +
 181 +static int brcmexp_gpio_get_polarity(struct gpio_chip *gc, unsigned int off)
 182 +{
 183 +       struct brcmexp_gpio *gpio;
 184 +       struct gpio_get_config get;
 185 +       int ret;
 186 +
 187 +       gpio = container_of(gc, struct brcmexp_gpio, gc);
 188 +
 189 +       get.gpio = off + gpio->gc.base; /* GPIO to update */
 190 +
 191 +       ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_CONFIG,
 192 +                                   &get, sizeof(get));
 193 +       if (ret) {
 194 +               dev_err(gpio->dev,
 195 +                       "Failed to get GPIO %u config (%d)\n", off, ret);
 196 +               return ret;
 197 +       }
 198 +       return get.polarity;
 199 +}
 200 +
 201 +static int brcmexp_gpio_dir_in(struct gpio_chip *gc, unsigned int off)
 202 +{
 203 +       struct brcmexp_gpio *gpio;
 204 +       struct gpio_set_config set_in;
 205 +       int ret;
 206 +
 207 +       gpio = container_of(gc, struct brcmexp_gpio, gc);
 208 +
 209 +       set_in.gpio = off + gpio->gc.base;      /* GPIO to update */
 210 +       set_in.direction = 0;           /* Input */
 211 +       set_in.polarity = brcmexp_gpio_get_polarity(gc, off);
 212 +                                       /* Retain existing setting */
 213 +       set_in.term_en = 0;             /* termination disabled */
 214 +       set_in.term_pull_up = 0;        /* n/a as termination disabled */
 215 +       set_in.state = 0;               /* n/a as configured as an input */
 216 +
 217 +       ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_CONFIG,
 218 +                                   &set_in, sizeof(set_in));
 219 +       if (ret) {
 220 +               dev_err(gpio->dev,
 221 +                       "Failed to set GPIO %u to input (%d)\n",
 222 +                       off, ret);
 223 +               return ret;
 224 +       }
 225 +       return 0;
 226 +}
 227 +
 228 +static int brcmexp_gpio_dir_out(struct gpio_chip *gc, unsigned int off, int val)
 229 +{
 230 +       struct brcmexp_gpio *gpio;
 231 +       struct gpio_set_config set_out;
 232 +       int ret;
 233 +
 234 +       gpio = container_of(gc, struct brcmexp_gpio, gc);
 235 +
 236 +       set_out.gpio = off + gpio->gc.base;     /* GPIO to update */
 237 +       set_out.direction = 1;          /* Output */
 238 +       set_out.polarity = brcmexp_gpio_get_polarity(gc, off);
 239 +                                       /* Retain existing setting */
 240 +       set_out.term_en = 0;            /* n/a as an output */
 241 +       set_out.term_pull_up = 0;       /* n/a as termination disabled */
 242 +       set_out.state = val;            /* Output state */
 243 +
 244 +       ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_CONFIG,
 245 +                                   &set_out, sizeof(set_out));
 246 +       if (ret) {
 247 +               dev_err(gpio->dev,
 248 +                       "Failed to set GPIO %u to output (%d)\n", off, ret);
 249 +               return ret;
 250 +       }
 251 +       return 0;
 252 +}
 253 +
 254 +static int brcmexp_gpio_get_direction(struct gpio_chip *gc, unsigned int off)
 255 +{
 256 +       struct brcmexp_gpio *gpio;
 257 +       struct gpio_get_config get;
 258 +       int ret;
 259 +
 260 +       gpio = container_of(gc, struct brcmexp_gpio, gc);
 261 +
 262 +       get.gpio = off + gpio->gc.base; /* GPIO to update */
 263 +
 264 +       ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_CONFIG,
 265 +                                   &get, sizeof(get));
 266 +       if (ret) {
 267 +               dev_err(gpio->dev,
 268 +                       "Failed to get GPIO %u config (%d)\n", off, ret);
 269 +               return ret;
 270 +       }
 271 +       return get.direction ? GPIOF_DIR_OUT : GPIOF_DIR_IN;
 272 +}
 273 +
 274 +static int brcmexp_gpio_get(struct gpio_chip *gc, unsigned int off)
 275 +{
 276 +       struct brcmexp_gpio *gpio;
 277 +       struct gpio_get_set_state get;
 278 +       int ret;
 279 +
 280 +       gpio = container_of(gc, struct brcmexp_gpio, gc);
 281 +
 282 +       get.gpio = off + gpio->gc.base; /* GPIO to update */
 283 +       get.state = 0;          /* storage for returned value */
 284 +
 285 +       ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_GET_GPIO_STATE,
 286 +                                        &get, sizeof(get));
 287 +       if (ret) {
 288 +               dev_err(gpio->dev,
 289 +                       "Failed to get GPIO %u state (%d)\n", off, ret);
 290 +               return ret;
 291 +       }
 292 +       return !!get.state;
 293 +}
 294 +
 295 +static void brcmexp_gpio_set(struct gpio_chip *gc, unsigned int off, int val)
 296 +{
 297 +       struct brcmexp_gpio *gpio;
 298 +       struct gpio_get_set_state set;
 299 +       int ret;
 300 +
 301 +       gpio = container_of(gc, struct brcmexp_gpio, gc);
 302 +
 303 +       off += gpio->gc.base;
 304 +
 305 +       set.gpio = off + gpio->gc.base; /* GPIO to update */
 306 +       set.state = val;        /* Output state */
 307 +
 308 +       ret = rpi_firmware_property(gpio->fw, RPI_FIRMWARE_SET_GPIO_STATE,
 309 +                                        &set, sizeof(set));
 310 +       if (ret)
 311 +               dev_err(gpio->dev,
 312 +                       "Failed to set GPIO %u state (%d)\n", off, ret);
 313 +}
 314 +
 315 +static int brcmexp_gpio_probe(struct platform_device *pdev)
 316 +{
 317 +       int err = 0;
 318 +       struct device *dev = &pdev->dev;
 319 +       struct device_node *np = dev->of_node;
 320 +       struct device_node *fw_node;
 321 +       struct rpi_firmware *fw;
 322 +       struct brcmexp_gpio *ucb;
 323 +
 324 +       fw_node = of_parse_phandle(np, "firmware", 0);
 325 +       if (!fw_node) {
 326 +               dev_err(dev, "Missing firmware node\n");
 327 +               return -ENOENT;
 328 +       }
 329 +
 330 +       fw = rpi_firmware_get(fw_node);
 331 +       if (!fw)
 332 +               return -EPROBE_DEFER;
 333 +
 334 +       ucb = devm_kzalloc(dev, sizeof(*ucb), GFP_KERNEL);
 335 +       if (!ucb)
 336 +               return -EINVAL;
 337 +
 338 +       ucb->fw = fw;
 339 +       ucb->dev = dev;
 340 +       ucb->gc.label = MODULE_NAME;
 341 +       ucb->gc.owner = THIS_MODULE;
 342 +       ucb->gc.of_node = np;
 343 +       ucb->gc.base = 128;
 344 +       ucb->gc.ngpio = NUM_GPIO;
 345 +
 346 +       ucb->gc.direction_input = brcmexp_gpio_dir_in;
 347 +       ucb->gc.direction_output = brcmexp_gpio_dir_out;
 348 +       ucb->gc.get_direction = brcmexp_gpio_get_direction;
 349 +       ucb->gc.get = brcmexp_gpio_get;
 350 +       ucb->gc.set = brcmexp_gpio_set;
 351 +       ucb->gc.can_sleep = true;
 352 +
 353 +       err = gpiochip_add(&ucb->gc);
 354 +       if (err)
 355 +               return err;
 356 +
 357 +       platform_set_drvdata(pdev, ucb);
 358 +
 359 +       return 0;
 360 +}
 361 +
 362 +static int brcmexp_gpio_remove(struct platform_device *pdev)
 363 +{
 364 +       struct brcmexp_gpio *ucb = platform_get_drvdata(pdev);
 365 +
 366 +       gpiochip_remove(&ucb->gc);
 367 +
 368 +       return 0;
 369 +}
 370 +
 371 +static const struct of_device_id __maybe_unused brcmexp_gpio_ids[] = {
 372 +       { .compatible = "brcm,bcm2835-expgpio" },
 373 +       { }
 374 +};
 375 +MODULE_DEVICE_TABLE(of, brcmexp_gpio_ids);
 376 +
 377 +static struct platform_driver brcmexp_gpio_driver = {
 378 +       .driver = {
 379 +               .name           = MODULE_NAME,
 380 +               .owner          = THIS_MODULE,
 381 +               .of_match_table = of_match_ptr(brcmexp_gpio_ids),
 382 +       },
 383 +       .probe  = brcmexp_gpio_probe,
 384 +       .remove = brcmexp_gpio_remove,
 385 +};
 386 +module_platform_driver(brcmexp_gpio_driver);
 387 +
 388 +MODULE_LICENSE("GPL");
 389 +MODULE_AUTHOR("Dave Stevenson <dave.stevenson@raspberrypi.org>");
 390 +MODULE_DESCRIPTION("brcm-exp GPIO driver");
 391 +MODULE_ALIAS("platform:brcmexp-gpio");
 392 --- a/include/soc/bcm2835/raspberrypi-firmware.h
 393 +++ b/include/soc/bcm2835/raspberrypi-firmware.h
 394 @@ -83,7 +83,11 @@ enum rpi_firmware_property_tag {
 395         RPI_FIRMWARE_SET_TURBO =                              0x00038009,
 396         RPI_FIRMWARE_SET_CUSTOMER_OTP =                       0x00038021,
 397         RPI_FIRMWARE_SET_DOMAIN_STATE =                       0x00038030,
 398 +       RPI_FIRMWARE_GET_GPIO_STATE =                         0x00030041,
 399 +       RPI_FIRMWARE_SET_GPIO_STATE =                         0x00038041,
 400         RPI_FIRMWARE_SET_SDHOST_CLOCK =                       0x00038042,
 401 +       RPI_FIRMWARE_GET_GPIO_CONFIG =                        0x00030043,
 402 +       RPI_FIRMWARE_SET_GPIO_CONFIG =                        0x00038043,
 403
 404         /* Dispmanx TAGS */
 405         RPI_FIRMWARE_FRAMEBUFFER_ALLOCATE =                   0x00040001,