drivers/platform/x86/intel_pmic_gpio.c

   1 /* Moorestown PMIC GPIO (access through IPC) driver
   2  * Copyright (c) 2008 - 2009, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  16  */
  17
  18 /* Supports:
  19  * Moorestown platform PMIC chip
  20  */
  21
  22 #define pr_fmt(fmt) "%s: " fmt, __func__
  23
  24 #include <linux/module.h>
  25 #include <linux/kernel.h>
  26 #include <linux/interrupt.h>
  27 #include <linux/delay.h>
  28 #include <linux/stddef.h>
  29 #include <linux/slab.h>
  30 #include <linux/ioport.h>
  31 #include <linux/init.h>
  32 #include <linux/io.h>
  33 #include <linux/gpio.h>
  34 #include <asm/intel_scu_ipc.h>
  35 #include <linux/device.h>
  36 #include <linux/intel_pmic_gpio.h>
  37 #include <linux/platform_device.h>
  38
  39 #define DRIVER_NAME "pmic_gpio"
  40
  41 /* register offset that IPC driver should use
  42  * 8 GPIO + 8 GPOSW (6 controllable) + 8GPO
  43  */
  44 enum pmic_gpio_register {
  45         GPIO0           = 0xE0,
  46         GPIO7           = 0xE7,
  47         GPIOINT         = 0xE8,
  48         GPOSWCTL0       = 0xEC,
  49         GPOSWCTL5       = 0xF1,
  50         GPO             = 0xF4,
  51 };
  52
  53 /* bits definition for GPIO & GPOSW */
  54 #define GPIO_DRV 0x01
  55 #define GPIO_DIR 0x02
  56 #define GPIO_DIN 0x04
  57 #define GPIO_DOU 0x08
  58 #define GPIO_INTCTL 0x30
  59 #define GPIO_DBC 0xc0
  60
  61 #define GPOSW_DRV 0x01
  62 #define GPOSW_DOU 0x08
  63 #define GPOSW_RDRV 0x30
  64
  65 #define GPIO_UPDATE_TYPE        0x80000000
  66
  67 #define NUM_GPIO 24
  68
  69 struct pmic_gpio {
  70         struct mutex            buslock;
  71         struct gpio_chip        chip;
  72         void                    *gpiointr;
  73         int                     irq;
  74         unsigned                irq_base;
  75         unsigned int            update_type;
  76         u32                     trigger_type;
  77 };
  78
  79 static void pmic_program_irqtype(int gpio, int type)
  80 {
  81         if (type & IRQ_TYPE_EDGE_RISING)
  82                 intel_scu_ipc_update_register(GPIO0 + gpio, 0x20, 0x20);
  83         else
  84                 intel_scu_ipc_update_register(GPIO0 + gpio, 0x00, 0x20);
  85
  86         if (type & IRQ_TYPE_EDGE_FALLING)
  87                 intel_scu_ipc_update_register(GPIO0 + gpio, 0x10, 0x10);
  88         else
  89                 intel_scu_ipc_update_register(GPIO0 + gpio, 0x00, 0x10);
  90 };
  91
  92 static int pmic_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
  93 {
  94         if (offset > 8) {
  95                 pr_err("only pin 0-7 support input\n");
  96                 return -1;/* we only have 8 GPIO can use as input */
  97         }
  98         return intel_scu_ipc_update_register(GPIO0 + offset,
  99                                                         GPIO_DIR, GPIO_DIR);
 100 }
 101
 102 static int pmic_gpio_direction_output(struct gpio_chip *chip,
 103                         unsigned offset, int value)
 104 {
 105         int rc = 0;
 106
 107         if (offset < 8)/* it is GPIO */
 108                 rc = intel_scu_ipc_update_register(GPIO0 + offset,
 109                                 GPIO_DRV | (value ? GPIO_DOU : 0),
 110                                 GPIO_DRV | GPIO_DOU | GPIO_DIR);
 111         else if (offset < 16)/* it is GPOSW */
 112                 rc = intel_scu_ipc_update_register(GPOSWCTL0 + offset - 8,
 113                                 GPOSW_DRV | (value ? GPOSW_DOU : 0),
 114                                 GPOSW_DRV | GPOSW_DOU | GPOSW_RDRV);
 115         else if (offset > 15 && offset < 24)/* it is GPO */
 116                 rc = intel_scu_ipc_update_register(GPO,
 117                                 value ? 1 << (offset - 16) : 0,
 118                                 1 << (offset - 16));
 119         else {
 120                 pr_err("invalid PMIC GPIO pin %d!\n", offset);
 121                 WARN_ON(1);
 122         }
 123
 124         return rc;
 125 }
 126
 127 static int pmic_gpio_get(struct gpio_chip *chip, unsigned offset)
 128 {
 129         u8 r;
 130         int ret;
 131
 132         /* we only have 8 GPIO pins we can use as input */
 133         if (offset > 8)
 134                 return -EOPNOTSUPP;
 135         ret = intel_scu_ipc_ioread8(GPIO0 + offset, &r);
 136         if (ret < 0)
 137                 return ret;
 138         return r & GPIO_DIN;
 139 }
 140
 141 static void pmic_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
 142 {
 143         if (offset < 8)/* it is GPIO */
 144                 intel_scu_ipc_update_register(GPIO0 + offset,
 145                         GPIO_DRV | (value ? GPIO_DOU : 0),
 146                         GPIO_DRV | GPIO_DOU);
 147         else if (offset < 16)/* it is GPOSW */
 148                 intel_scu_ipc_update_register(GPOSWCTL0 + offset - 8,
 149                         GPOSW_DRV | (value ? GPOSW_DOU : 0),
 150                         GPOSW_DRV | GPOSW_DOU | GPOSW_RDRV);
 151         else if (offset > 15 && offset < 24) /* it is GPO */
 152                 intel_scu_ipc_update_register(GPO,
 153                         value ? 1 << (offset - 16) : 0,
 154                         1 << (offset - 16));
 155 }
 156
 157 /*
 158  * This is called from genirq with pg->buslock locked and
 159  * irq_desc->lock held. We can not access the scu bus here, so we
 160  * store the change and update in the bus_sync_unlock() function below
 161  */
 162 static int pmic_irq_type(struct irq_data *data, unsigned type)
 163 {
 164         struct pmic_gpio *pg = irq_data_get_irq_chip_data(data);
 165         u32 gpio = data->irq - pg->irq_base;
 166
 167         if (gpio >= pg->chip.ngpio)
 168                 return -EINVAL;
 169
 170         pg->trigger_type = type;
 171         pg->update_type = gpio | GPIO_UPDATE_TYPE;
 172         return 0;
 173 }
 174
 175 static int pmic_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
 176 {
 177         struct pmic_gpio *pg = container_of(chip, struct pmic_gpio, chip);
 178
 179         return pg->irq_base + offset;
 180 }
 181
 182 static void pmic_bus_lock(struct irq_data *data)
 183 {
 184         struct pmic_gpio *pg = irq_data_get_irq_chip_data(data);
 185
 186         mutex_lock(&pg->buslock);
 187 }
 188
 189 static void pmic_bus_sync_unlock(struct irq_data *data)
 190 {
 191         struct pmic_gpio *pg = irq_data_get_irq_chip_data(data);
 192
 193         if (pg->update_type) {
 194                 unsigned int gpio = pg->update_type & ~GPIO_UPDATE_TYPE;
 195
 196                 pmic_program_irqtype(gpio, pg->trigger_type);
 197                 pg->update_type = 0;
 198         }
 199         mutex_unlock(&pg->buslock);
 200 }
 201
 202 /* the gpiointr register is read-clear, so just do nothing. */
 203 static void pmic_irq_unmask(struct irq_data *data) { }
 204
 205 static void pmic_irq_mask(struct irq_data *data) { }
 206
 207 static struct irq_chip pmic_irqchip = {
 208         .name                   = "PMIC-GPIO",
 209         .irq_mask               = pmic_irq_mask,
 210         .irq_unmask             = pmic_irq_unmask,
 211         .irq_set_type           = pmic_irq_type,
 212         .irq_bus_lock           = pmic_bus_lock,
 213         .irq_bus_sync_unlock    = pmic_bus_sync_unlock,
 214 };
 215
 216 static irqreturn_t pmic_irq_handler(int irq, void *data)
 217 {
 218         struct pmic_gpio *pg = data;
 219         u8 intsts = *((u8 *)pg->gpiointr + 4);
 220         int gpio;
 221         irqreturn_t ret = IRQ_NONE;
 222
 223         for (gpio = 0; gpio < 8; gpio++) {
 224                 if (intsts & (1 << gpio)) {
 225                         pr_debug("pmic pin %d triggered\n", gpio);
 226                         generic_handle_irq(pg->irq_base + gpio);
 227                         ret = IRQ_HANDLED;
 228                 }
 229         }
 230         return ret;
 231 }
 232
 233 static int platform_pmic_gpio_probe(struct platform_device *pdev)
 234 {
 235         struct device *dev = &pdev->dev;
 236         int irq = platform_get_irq(pdev, 0);
 237         struct intel_pmic_gpio_platform_data *pdata = dev->platform_data;
 238
 239         struct pmic_gpio *pg;
 240         int retval;
 241         int i;
 242
 243         if (irq < 0) {
 244                 dev_dbg(dev, "no IRQ line\n");
 245                 return -EINVAL;
 246         }
 247
 248         if (!pdata || !pdata->gpio_base || !pdata->irq_base) {
 249                 dev_dbg(dev, "incorrect or missing platform data\n");
 250                 return -EINVAL;
 251         }
 252
 253         pg = kzalloc(sizeof(*pg), GFP_KERNEL);
 254         if (!pg)
 255                 return -ENOMEM;
 256
 257         dev_set_drvdata(dev, pg);
 258
 259         pg->irq = irq;
 260         /* setting up SRAM mapping for GPIOINT register */
 261         pg->gpiointr = ioremap_nocache(pdata->gpiointr, 8);
 262         if (!pg->gpiointr) {
 263                 pr_err("Can not map GPIOINT\n");
 264                 retval = -EINVAL;
 265                 goto err2;
 266         }
 267         pg->irq_base = pdata->irq_base;
 268         pg->chip.label = "intel_pmic";
 269         pg->chip.direction_input = pmic_gpio_direction_input;
 270         pg->chip.direction_output = pmic_gpio_direction_output;
 271         pg->chip.get = pmic_gpio_get;
 272         pg->chip.set = pmic_gpio_set;
 273         pg->chip.to_irq = pmic_gpio_to_irq;
 274         pg->chip.base = pdata->gpio_base;
 275         pg->chip.ngpio = NUM_GPIO;
 276         pg->chip.can_sleep = 1;
 277         pg->chip.dev = dev;
 278
 279         mutex_init(&pg->buslock);
 280
 281         pg->chip.dev = dev;
 282         retval = gpiochip_add(&pg->chip);
 283         if (retval) {
 284                 pr_err("Can not add pmic gpio chip\n");
 285                 goto err;
 286         }
 287
 288         retval = request_irq(pg->irq, pmic_irq_handler, 0, "pmic", pg);
 289         if (retval) {
 290                 pr_warn("Interrupt request failed\n");
 291                 goto fail_request_irq;
 292         }
 293
 294         for (i = 0; i < 8; i++) {
 295                 irq_set_chip_and_handler_name(i + pg->irq_base,
 296                                               &pmic_irqchip,
 297                                               handle_simple_irq,
 298                                               "demux");
 299                 irq_set_chip_data(i + pg->irq_base, pg);
 300         }
 301         return 0;
 302
 303 fail_request_irq:
 304         if (gpiochip_remove(&pg->chip))
 305                 pr_err("gpiochip_remove failed\n");
 306 err:
 307         iounmap(pg->gpiointr);
 308 err2:
 309         kfree(pg);
 310         return retval;
 311 }
 312
 313 /* at the same time, register a platform driver
 314  * this supports the sfi 0.81 fw */
 315 static struct platform_driver platform_pmic_gpio_driver = {
 316         .driver = {
 317                 .name           = DRIVER_NAME,
 318                 .owner          = THIS_MODULE,
 319         },
 320         .probe          = platform_pmic_gpio_probe,
 321 };
 322
 323 static int __init platform_pmic_gpio_init(void)
 324 {
 325         return platform_driver_register(&platform_pmic_gpio_driver);
 326 }
 327
 328 subsys_initcall(platform_pmic_gpio_init);
 329
 330 MODULE_AUTHOR("Alek Du <alek.du@intel.com>");
 331 MODULE_DESCRIPTION("Intel Moorestown PMIC GPIO driver");
 332 MODULE_LICENSE("GPL v2");