target/linux/brcm63xx/patches-2.6.32/211-nxp-74hc164-gpio-chip-driver.patch

   1 --- a/drivers/gpio/Kconfig
   2 +++ b/drivers/gpio/Kconfig
   3 @@ -230,4 +230,12 @@ config GPIO_UCB1400
   4           To compile this driver as a module, choose M here: the
   5           module will be called ucb1400_gpio.
   6
   7 +comment "Other GPIO expanders"
   8 +
   9 +config GPIO_NXP_74HC164
  10 +       tristate "NXP 74HC164 Output expanders"
  11 +       help
  12 +         Platform driver for NXP 74HC164 8-output Expanders. This
  13 +         provides a GPIO interface supporting outputs.
  14 +
  15  endif
  16 --- a/drivers/gpio/Makefile
  17 +++ b/drivers/gpio/Makefile
  18 @@ -10,6 +10,7 @@ obj-$(CONFIG_GPIO_MAX7301)    += max7301.o
  19  obj-$(CONFIG_GPIO_MAX732X)     += max732x.o
  20  obj-$(CONFIG_GPIO_MC33880)     += mc33880.o
  21  obj-$(CONFIG_GPIO_MCP23S08)    += mcp23s08.o
  22 +obj-$(CONFIG_GPIO_NXP_74HC164) += nxp_74hc164.o
  23  obj-$(CONFIG_GPIO_PCA953X)     += pca953x.o
  24  obj-$(CONFIG_GPIO_PCF857X)     += pcf857x.o
  25  obj-$(CONFIG_GPIO_PL061)       += pl061.o
  26 --- /dev/null
  27 +++ b/drivers/gpio/nxp_74hc164.c
  28 @@ -0,0 +1,226 @@
  29 +/*
  30 + *  NXP 74HC164 - output expander  GPIO driver
  31 + *
  32 + *  Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
  33 + *  Copyright (C) 2010 Miguel Gaio <miguel.gaio@efixo.com>
  34 + *
  35 + *  This program is free software; you can redistribute it and/or modify
  36 + *  it under the terms of the GNU General Public License version 2 as
  37 + *  published by the Free Software Foundation.
  38 + *
  39 + *  Copy from nxp_74hc153.c code
  40 + */
  41 +
  42 +#include <linux/module.h>
  43 +#include <linux/init.h>
  44 +#include <linux/gpio.h>
  45 +#include <linux/bitops.h>
  46 +#include <linux/platform_device.h>
  47 +#include <linux/nxp_74hc164.h>
  48 +
  49 +#define NXP_74HC164_NUM_GPIOS  8
  50 +
  51 +struct nxp_74hc164_chip {
  52 +       struct device           *parent;
  53 +       struct gpio_chip        gpio_chip;
  54 +       struct mutex            lock;
  55 +       long                    mask;
  56 +};
  57 +
  58 +static void nxp_74hc164_set_value(struct gpio_chip *, unsigned, int);
  59 +
  60 +static struct nxp_74hc164_chip *gpio_to_nxp(struct gpio_chip *gc)
  61 +{
  62 +       return container_of(gc, struct nxp_74hc164_chip, gpio_chip);
  63 +}
  64 +
  65 +static int nxp_74hc164_direction_input(struct gpio_chip *gc, unsigned offset)
  66 +{
  67 +       WARN_ON(1);
  68 +       return -EINVAL;
  69 +}
  70 +
  71 +static int nxp_74hc164_direction_output(struct gpio_chip *gc,
  72 +                                       unsigned offset, int val)
  73 +{
  74 +       nxp_74hc164_set_value(gc, offset, val);
  75 +       return 0;
  76 +}
  77 +
  78 +static int nxp_74hc164_get_value(struct gpio_chip *gc, unsigned offset)
  79 +{
  80 +       struct nxp_74hc164_chip *nxp = gpio_to_nxp(gc);
  81 +       int ret;
  82 +
  83 +       mutex_lock(&nxp->lock);
  84 +       ret = test_bit(offset, &nxp->mask);
  85 +       mutex_unlock(&nxp->lock);
  86 +
  87 +       return ret;
  88 +}
  89 +
  90 +static void nxp_74hc164_set_value(struct gpio_chip *gc,
  91 +                                 unsigned offset, int val)
  92 +{
  93 +       struct nxp_74hc164_chip *nxp;
  94 +       struct nxp_74hc164_platform_data *pdata;
  95 +       long mask;
  96 +       int refresh;
  97 +       int i;
  98 +
  99 +       nxp = gpio_to_nxp(gc);
 100 +       pdata = nxp->parent->platform_data;
 101 +
 102 +       mutex_lock(&nxp->lock);
 103 +       if (val)
 104 +               refresh = (test_and_set_bit(offset, &nxp->mask) != val);
 105 +       else
 106 +               refresh = (test_and_clear_bit(offset, &nxp->mask) != val);
 107 +
 108 +       if (refresh) {
 109 +               mask = nxp->mask;
 110 +               for (i = 8; i > 0; --i, mask <<= 1) {
 111 +                       gpio_set_value(pdata->gpio_pin_data, mask & 0x80);
 112 +                       gpio_set_value(pdata->gpio_pin_clk, 1);
 113 +                       gpio_set_value(pdata->gpio_pin_clk, 0);
 114 +               }
 115 +       }
 116 +       mutex_unlock(&nxp->lock);
 117 +}
 118 +
 119 +static int __devinit nxp_74hc164_probe(struct platform_device *pdev)
 120 +{
 121 +       struct nxp_74hc164_platform_data *pdata;
 122 +       struct nxp_74hc164_chip *nxp;
 123 +       struct gpio_chip *gc;
 124 +       int err;
 125 +
 126 +       pdata = pdev->dev.platform_data;
 127 +       if (pdata == NULL) {
 128 +               dev_dbg(&pdev->dev, "no platform data specified\n");
 129 +               return -EINVAL;
 130 +       }
 131 +
 132 +       nxp = kzalloc(sizeof(struct nxp_74hc164_chip), GFP_KERNEL);
 133 +       if (nxp == NULL) {
 134 +               dev_err(&pdev->dev, "no memory for private data\n");
 135 +               return -ENOMEM;
 136 +       }
 137 +
 138 +       err = gpio_request(pdata->gpio_pin_clk, dev_name(&pdev->dev));
 139 +       if (err) {
 140 +               dev_err(&pdev->dev, "unable to claim gpio %u, err=%d\n",
 141 +                       pdata->gpio_pin_clk, err);
 142 +               goto err_free_nxp;
 143 +       }
 144 +
 145 +       err = gpio_request(pdata->gpio_pin_data, dev_name(&pdev->dev));
 146 +       if (err) {
 147 +               dev_err(&pdev->dev, "unable to claim gpio %u, err=%d\n",
 148 +                       pdata->gpio_pin_data, err);
 149 +               goto err_free_clk;
 150 +       }
 151 +
 152 +       err = gpio_direction_output(pdata->gpio_pin_clk, 0);
 153 +       if (err) {
 154 +               dev_err(&pdev->dev,
 155 +                       "unable to set direction of gpio %u, err=%d\n",
 156 +                       pdata->gpio_pin_clk, err);
 157 +               goto err_free_data;
 158 +       }
 159 +
 160 +       err = gpio_direction_output(pdata->gpio_pin_data, 0);
 161 +       if (err) {
 162 +               dev_err(&pdev->dev,
 163 +                       "unable to set direction of gpio %u, err=%d\n",
 164 +                       pdata->gpio_pin_data, err);
 165 +               goto err_free_data;
 166 +       }
 167 +
 168 +       nxp->parent = &pdev->dev;
 169 +       mutex_init(&nxp->lock);
 170 +
 171 +       gc = &nxp->gpio_chip;
 172 +
 173 +       gc->direction_input  = nxp_74hc164_direction_input;
 174 +       gc->direction_output = nxp_74hc164_direction_output;
 175 +       gc->get = nxp_74hc164_get_value;
 176 +       gc->set = nxp_74hc164_set_value;
 177 +       gc->can_sleep = 1;
 178 +
 179 +       gc->base = pdata->gpio_base;
 180 +       gc->ngpio = NXP_74HC164_NUM_GPIOS;
 181 +       gc->label = dev_name(nxp->parent);
 182 +       gc->dev = nxp->parent;
 183 +       gc->owner = THIS_MODULE;
 184 +
 185 +       err = gpiochip_add(&nxp->gpio_chip);
 186 +       if (err) {
 187 +               dev_err(&pdev->dev, "unable to add gpio chip, err=%d\n", err);
 188 +               goto err_free_data;
 189 +       }
 190 +
 191 +       platform_set_drvdata(pdev, nxp);
 192 +       return 0;
 193 +
 194 + err_free_data:
 195 +       gpio_free(pdata->gpio_pin_data);
 196 + err_free_clk:
 197 +       gpio_free(pdata->gpio_pin_clk);
 198 + err_free_nxp:
 199 +       kfree(nxp);
 200 +       return err;
 201 +}
 202 +
 203 +static int nxp_74hc164_remove(struct platform_device *pdev)
 204 +{
 205 +       struct nxp_74hc164_chip *nxp = platform_get_drvdata(pdev);
 206 +       struct nxp_74hc164_platform_data *pdata = pdev->dev.platform_data;
 207 +
 208 +       if (nxp) {
 209 +               int err;
 210 +
 211 +               err = gpiochip_remove(&nxp->gpio_chip);
 212 +               if (err) {
 213 +                       dev_err(&pdev->dev,
 214 +                               "unable to remove gpio chip, err=%d\n",
 215 +                               err);
 216 +                       return err;
 217 +               }
 218 +
 219 +               gpio_free(pdata->gpio_pin_clk);
 220 +               gpio_free(pdata->gpio_pin_data);
 221 +
 222 +               kfree(nxp);
 223 +               platform_set_drvdata(pdev, NULL);
 224 +       }
 225 +
 226 +       return 0;
 227 +}
 228 +
 229 +static struct platform_driver nxp_74hc164_driver = {
 230 +       .probe          = nxp_74hc164_probe,
 231 +       .remove         = __devexit_p(nxp_74hc164_remove),
 232 +       .driver = {
 233 +               .name   = NXP_74HC164_DRIVER_NAME,
 234 +               .owner  = THIS_MODULE,
 235 +       },
 236 +};
 237 +
 238 +static int __init nxp_74hc164_init(void)
 239 +{
 240 +       return platform_driver_register(&nxp_74hc164_driver);
 241 +}
 242 +subsys_initcall(nxp_74hc164_init);
 243 +
 244 +static void __exit nxp_74hc164_exit(void)
 245 +{
 246 +       platform_driver_unregister(&nxp_74hc164_driver);
 247 +}
 248 +module_exit(nxp_74hc164_exit);
 249 +
 250 +MODULE_AUTHOR("Gabor Juhos <juhosg@openwrt.org>");
 251 +MODULE_AUTHOR("Miguel Gaio <miguel.gaio@efixo.com>");
 252 +MODULE_DESCRIPTION("GPIO expander driver for NXP 74HC164");
 253 +MODULE_LICENSE("GPL v2");
 254 +MODULE_ALIAS("platform:" NXP_74HC164_DRIVER_NAME);
 255 --- /dev/null
 256 +++ b/include/linux/nxp_74hc164.h
 257 @@ -0,0 +1,22 @@
 258 +/*
 259 + *  NXP 74HC164 - Dual 4-input multiplexer defines
 260 + *
 261 + *  Copyright (C) 2010 Gabor Juhos <juhosg@openwrt.org>
 262 + *
 263 + *  This program is free software; you can redistribute it and/or modify
 264 + *  it under the terms of the GNU General Public License version 2 as
 265 + *  published by the Free Software Foundation.
 266 + */
 267 +
 268 +#ifndef _NXP_74HC164_H
 269 +#define _NXP_74HC164_H
 270 +
 271 +#define NXP_74HC164_DRIVER_NAME "nxp-74hc164"
 272 +
 273 +struct nxp_74hc164_platform_data {
 274 +       unsigned        gpio_base;
 275 +       unsigned        gpio_pin_data;
 276 +       unsigned        gpio_pin_clk;
 277 +};
 278 +
 279 +#endif /* _NXP_74HC164_H */