target/linux/rdc/patches-2.6.32/002-rdc321x_gpio.patch

   1 This patch adds a new GPIO driver for the RDC321x SoC GPIO controller.
   2
   3 Signed-off-by: Florian Fainelli <florian@openwrt.org>
   4 ---
   5 Changes from v2:
   6 - initialize spinlock earlier
   7 - do not declare and assign gpch variables on the same line
   8 - use the pci_dev pointer passed as platform data
   9 - replaced rdc321x_pci_{read,write}
  10
  11 Index: linux-2.6.32.10/drivers/gpio/Kconfig
  12 ===================================================================
  13 --- linux-2.6.32.10.orig/drivers/gpio/Kconfig   2010-05-15 22:54:31.000000000 +0200
  14 +++ linux-2.6.32.10/drivers/gpio/Kconfig        2010-05-15 22:54:51.000000000 +0200
  15 @@ -196,6 +196,14 @@
  16         help
  17           Say Y here to support Intel Moorestown platform GPIO.
  18
  19 +config GPIO_RDC321X
  20 +       tristate "RDC R-321x GPIO support"
  21 +       depends on PCI && GPIOLIB
  22 +       select MFD_RDC321X
  23 +       help
  24 +         Support for the RDC R321x SoC GPIOs over southbridge
  25 +         PCI configuration space.
  26 +
  27  comment "SPI GPIO expanders:"
  28
  29  config GPIO_MAX7301
  30 Index: linux-2.6.32.10/drivers/gpio/Makefile
  31 ===================================================================
  32 --- linux-2.6.32.10.orig/drivers/gpio/Makefile  2010-05-15 22:54:31.000000000 +0200
  33 +++ linux-2.6.32.10/drivers/gpio/Makefile       2010-05-15 22:54:51.000000000 +0200
  34 @@ -19,3 +19,4 @@
  35  obj-$(CONFIG_GPIO_BT8XX)       += bt8xxgpio.o
  36  obj-$(CONFIG_GPIO_VR41XX)      += vr41xx_giu.o
  37  obj-$(CONFIG_GPIO_WM831X)      += wm831x-gpio.o
  38 +obj-$(CONFIG_GPIO_RDC321X)     += rdc321x-gpio.o
  39 Index: linux-2.6.32.10/drivers/gpio/rdc321x-gpio.c
  40 ===================================================================
  41 --- /dev/null   1970-01-01 00:00:00.000000000 +0000
  42 +++ linux-2.6.32.10/drivers/gpio/rdc321x-gpio.c 2010-05-15 22:55:10.000000000 +0200
  43 @@ -0,0 +1,245 @@
  44 +/*
  45 + * RDC321x GPIO driver
  46 + *
  47 + * Copyright (C) 2008, Volker Weiss <dev@tintuc.de>
  48 + * Copyright (C) 2007-2010 Florian Fainelli <florian@openwrt.org>
  49 + *
  50 + * This program is free software; you can redistribute it and/or modify
  51 + * it under the terms of the GNU General Public License as published by
  52 + * the Free Software Foundation; either version 2 of the License, or
  53 + * (at your option) any later version.
  54 + *
  55 + * This program is distributed in the hope that it will be useful,
  56 + * but WITHOUT ANY WARRANTY; without even the implied warranty of
  57 + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  58 + * GNU General Public License for more details.
  59 + *
  60 + * You should have received a copy of the GNU General Public License
  61 + * along with this program; if not, write to the Free Software
  62 + * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  63 + *
  64 + */
  65 +#include <linux/module.h>
  66 +#include <linux/kernel.h>
  67 +#include <linux/init.h>
  68 +#include <linux/spinlock.h>
  69 +#include <linux/platform_device.h>
  70 +#include <linux/pci.h>
  71 +#include <linux/gpio.h>
  72 +#include <linux/mfd/rdc321x.h>
  73 +
  74 +struct rdc321x_gpio {
  75 +       spinlock_t              lock;
  76 +       struct pci_dev          *sb_pdev;
  77 +       u32                     data_reg[2];
  78 +       int                     reg1_ctrl_base;
  79 +       int                     reg1_data_base;
  80 +       int                     reg2_ctrl_base;
  81 +       int                     reg2_data_base;
  82 +       struct gpio_chip        chip;
  83 +};
  84 +
  85 +/* read GPIO pin */
  86 +static int rdc_gpio_get_value(struct gpio_chip *chip, unsigned gpio)
  87 +{
  88 +       struct rdc321x_gpio *gpch;
  89 +       u32 value = 0;
  90 +       int reg;
  91 +
  92 +       gpch = container_of(chip, struct rdc321x_gpio, chip);
  93 +       reg = gpio < 32 ? gpch->reg1_data_base : gpch->reg2_data_base;
  94 +
  95 +       spin_lock(&gpch->lock);
  96 +       pci_write_config_dword(gpch->sb_pdev, reg,
  97 +                                       gpch->data_reg[gpio < 32 ? 0 : 1]);
  98 +       pci_read_config_dword(gpch->sb_pdev, reg, &value);
  99 +       spin_unlock(&gpch->lock);
 100 +
 101 +       return (1 << (gpio & 0x1f)) & value ? 1 : 0;
 102 +}
 103 +
 104 +static void rdc_gpio_set_value_impl(struct gpio_chip *chip,
 105 +                               unsigned gpio, int value)
 106 +{
 107 +       struct rdc321x_gpio *gpch;
 108 +       int reg = (gpio < 32) ? 0 : 1;
 109 +
 110 +       gpch = container_of(chip, struct rdc321x_gpio, chip);
 111 +
 112 +       if (value)
 113 +               gpch->data_reg[reg] |= 1 << (gpio & 0x1f);
 114 +       else
 115 +               gpch->data_reg[reg] &= ~(1 << (gpio & 0x1f));
 116 +
 117 +       pci_write_config_dword(gpch->sb_pdev,
 118 +                       reg ? gpch->reg2_data_base : gpch->reg1_data_base,
 119 +                       gpch->data_reg[reg]);
 120 +}
 121 +
 122 +/* set GPIO pin to value */
 123 +static void rdc_gpio_set_value(struct gpio_chip *chip,
 124 +                               unsigned gpio, int value)
 125 +{
 126 +       struct rdc321x_gpio *gpch;
 127 +
 128 +       gpch = container_of(chip, struct rdc321x_gpio, chip);
 129 +       spin_lock(&gpch->lock);
 130 +       rdc_gpio_set_value_impl(chip, gpio, value);
 131 +       spin_unlock(&gpch->lock);
 132 +}
 133 +
 134 +static int rdc_gpio_config(struct gpio_chip *chip,
 135 +                               unsigned gpio, int value)
 136 +{
 137 +       struct rdc321x_gpio *gpch;
 138 +       int err;
 139 +       u32 reg;
 140 +
 141 +       gpch = container_of(chip, struct rdc321x_gpio, chip);
 142 +
 143 +       spin_lock(&gpch->lock);
 144 +       err = pci_read_config_dword(gpch->sb_pdev, gpio < 32 ?
 145 +                       gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, &reg);
 146 +       if (err)
 147 +               goto unlock;
 148 +
 149 +       reg |= 1 << (gpio & 0x1f);
 150 +
 151 +       err = pci_write_config_dword(gpch->sb_pdev, gpio < 32 ?
 152 +                       gpch->reg1_ctrl_base : gpch->reg2_ctrl_base, reg);
 153 +       if (err)
 154 +               goto unlock;
 155 +
 156 +       rdc_gpio_set_value_impl(chip, gpio, value);
 157 +
 158 +unlock:
 159 +       spin_unlock(&gpch->lock);
 160 +
 161 +       return err;
 162 +}
 163 +
 164 +/* configure GPIO pin as input */
 165 +static int rdc_gpio_direction_input(struct gpio_chip *chip, unsigned gpio)
 166 +{
 167 +       return rdc_gpio_config(chip, gpio, 1);
 168 +}
 169 +
 170 +/*
 171 + * Cache the initial value of both GPIO data registers
 172 + */
 173 +static int __devinit rdc321x_gpio_probe(struct platform_device *pdev)
 174 +{
 175 +       int err;
 176 +       struct resource *r;
 177 +       struct rdc321x_gpio *rdc321x_gpio_dev;
 178 +       struct rdc321x_gpio_pdata *pdata;
 179 +
 180 +       pdata = platform_get_drvdata(pdev);
 181 +       if (!pdata) {
 182 +               dev_err(&pdev->dev, "no platform data supplied\n");
 183 +               return -ENODEV;
 184 +       }
 185 +
 186 +       rdc321x_gpio_dev = kzalloc(sizeof(struct rdc321x_gpio), GFP_KERNEL);
 187 +       if (!rdc321x_gpio_dev) {
 188 +               dev_err(&pdev->dev, "failed to allocate private data\n");
 189 +               return -ENOMEM;
 190 +       }
 191 +
 192 +       r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg1");
 193 +       if (!r) {
 194 +               dev_err(&pdev->dev, "failed to get gpio-reg1 resource\n");
 195 +               err = -ENODEV;
 196 +               goto out_free;
 197 +       }
 198 +
 199 +       spin_lock_init(&rdc321x_gpio_dev->lock);
 200 +       rdc321x_gpio_dev->sb_pdev = pdata->sb_pdev;
 201 +       rdc321x_gpio_dev->reg1_ctrl_base = r->start;
 202 +       rdc321x_gpio_dev->reg1_data_base = r->start + 0x4;
 203 +
 204 +       r = platform_get_resource_byname(pdev, IORESOURCE_IO, "gpio-reg2");
 205 +       if (!r) {
 206 +               dev_err(&pdev->dev, "failed to get gpio-reg2 resource\n");
 207 +               err = -ENODEV;
 208 +               goto out_free;
 209 +       }
 210 +
 211 +       rdc321x_gpio_dev->reg2_ctrl_base = r->start;
 212 +       rdc321x_gpio_dev->reg2_data_base = r->start + 0x4;
 213 +
 214 +       rdc321x_gpio_dev->chip.label = "rdc321x-gpio";
 215 +       rdc321x_gpio_dev->chip.direction_input = rdc_gpio_direction_input;
 216 +       rdc321x_gpio_dev->chip.direction_output = rdc_gpio_config;
 217 +       rdc321x_gpio_dev->chip.get = rdc_gpio_get_value;
 218 +       rdc321x_gpio_dev->chip.set = rdc_gpio_set_value;
 219 +       rdc321x_gpio_dev->chip.base = 0;
 220 +       rdc321x_gpio_dev->chip.ngpio = pdata->max_gpios;
 221 +
 222 +       platform_set_drvdata(pdev, rdc321x_gpio_dev);
 223 +
 224 +       /* This might not be, what others (BIOS, bootloader, etc.)
 225 +          wrote to these registers before, but it's a good guess. Still
 226 +          better than just using 0xffffffff. */
 227 +       err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
 228 +                                       rdc321x_gpio_dev->reg1_data_base,
 229 +                                       &rdc321x_gpio_dev->data_reg[0]);
 230 +       if (err)
 231 +               goto out_drvdata;
 232 +
 233 +       err = pci_read_config_dword(rdc321x_gpio_dev->sb_pdev,
 234 +                                       rdc321x_gpio_dev->reg2_data_base,
 235 +                                       &rdc321x_gpio_dev->data_reg[1]);
 236 +       if (err)
 237 +               goto out_drvdata;
 238 +
 239 +       dev_info(&pdev->dev, "registering %d GPIOs\n",
 240 +                                       rdc321x_gpio_dev->chip.ngpio);
 241 +       return gpiochip_add(&rdc321x_gpio_dev->chip);
 242 +
 243 +out_drvdata:
 244 +       platform_set_drvdata(pdev, NULL);
 245 +out_free:
 246 +       kfree(rdc321x_gpio_dev);
 247 +       return err;
 248 +}
 249 +
 250 +static int __devexit rdc321x_gpio_remove(struct platform_device *pdev)
 251 +{
 252 +       int ret;
 253 +       struct rdc321x_gpio *rdc321x_gpio_dev = platform_get_drvdata(pdev);
 254 +
 255 +       ret = gpiochip_remove(&rdc321x_gpio_dev->chip);
 256 +       if (ret)
 257 +               dev_err(&pdev->dev, "failed to unregister chip\n");
 258 +
 259 +       kfree(rdc321x_gpio_dev);
 260 +       platform_set_drvdata(pdev, NULL);
 261 +
 262 +       return ret;
 263 +}
 264 +
 265 +static struct platform_driver rdc321x_gpio_driver = {
 266 +       .driver.name    = "rdc321x-gpio",
 267 +       .driver.owner   = THIS_MODULE,
 268 +       .probe          = rdc321x_gpio_probe,
 269 +       .remove         = __devexit_p(rdc321x_gpio_remove),
 270 +};
 271 +
 272 +static int __init rdc321x_gpio_init(void)
 273 +{
 274 +       return platform_driver_register(&rdc321x_gpio_driver);
 275 +}
 276 +
 277 +static void __exit rdc321x_gpio_exit(void)
 278 +{
 279 +       platform_driver_unregister(&rdc321x_gpio_driver);
 280 +}
 281 +
 282 +module_init(rdc321x_gpio_init);
 283 +module_exit(rdc321x_gpio_exit);
 284 +
 285 +MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
 286 +MODULE_DESCRIPTION("RDC321x GPIO driver");
 287 +MODULE_LICENSE("GPL");
 288 +MODULE_ALIAS("platform:rdc321x-gpio");