mfd: Add HTCPLD driver
authorCory Maccarrone <darkstar6262@gmail.com>
Tue, 19 Jan 2010 10:22:45 +0000 (11:22 +0100)
committerSamuel Ortiz <sameo@linux.intel.com>
Sun, 7 Mar 2010 21:17:09 +0000 (22:17 +0100)
This change introduces a driver for the HTC PLD chip found
on some smartphones, such as the HTC Wizard and HTC Herald.
It works through the I2C bus and acts as a GPIO extender.
Specifically:

 * it can have several sub-devices, each with its own I2C
   address
 * Each sub-device provides 8 output and 8 input pins
 * The chip attaches to one GPIO to signal when any of the
   input GPIOs change -- at which point all chips must be
   scanned for changes

This driver implements the GPIOs throught the kernel's
GPIO and IRQ framework.  This allows any GPIO-servicing
drivers to operate on htcpld pins, such as the gpio-keys
and gpio-leds drivers.

Signed-off-by: Cory Maccarrone <darkstar6262@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
drivers/mfd/Kconfig
drivers/mfd/Makefile
drivers/mfd/htc-i2cpld.c [new file with mode: 0644]
include/linux/htcpld.h [new file with mode: 0644]

index d63ab2e..9bcd447 100644 (file)
@@ -78,6 +78,15 @@ config HTC_PASIC3
          HTC Magician devices, respectively. Actual functionality is
          handled by the leds-pasic3 and ds1wm drivers.
 
+config HTC_I2CPLD
+       bool "HTC I2C PLD chip support"
+       depends on I2C=y
+       help
+         If you say yes here you get support for the supposed CPLD
+         found on omap850 HTC devices like the HTC Wizard and HTC Herald.
+         This device provides input and output GPIOs through an I2C
+         interface to one or more sub-chips.
+
 config UCB1400_CORE
        tristate "Philips UCB1400 Core driver"
        depends on AC97_BUS
index 2616357..142d312 100644 (file)
@@ -10,6 +10,7 @@ obj-$(CONFIG_MFD_SH_MOBILE_SDHI)              += sh_mobile_sdhi.o
 
 obj-$(CONFIG_HTC_EGPIO)                += htc-egpio.o
 obj-$(CONFIG_HTC_PASIC3)       += htc-pasic3.o
+obj-$(CONFIG_HTC_I2CPLD)       += htc-i2cpld.o
 
 obj-$(CONFIG_MFD_DM355EVM_MSP) += dm355evm_msp.o
 
diff --git a/drivers/mfd/htc-i2cpld.c b/drivers/mfd/htc-i2cpld.c
new file mode 100644 (file)
index 0000000..37b9fda
--- /dev/null
@@ -0,0 +1,710 @@
+/*
+ *  htc-i2cpld.c
+ *  Chip driver for an unknown CPLD chip found on omap850 HTC devices like
+ *  the HTC Wizard and HTC Herald.
+ *  The cpld is located on the i2c bus and acts as an input/output GPIO
+ *  extender.
+ *
+ *  Copyright (C) 2009 Cory Maccarrone <darkstar6262@gmail.com>
+ *
+ *  Based on work done in the linwizard project
+ *  Copyright (C) 2008-2009 Angelo Arrifano <miknix@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/i2c.h>
+#include <linux/irq.h>
+#include <linux/spinlock.h>
+#include <linux/htcpld.h>
+#include <linux/gpio.h>
+
+struct htcpld_chip {
+       spinlock_t              lock;
+
+       /* chip info */
+       u8                      reset;
+       u8                      addr;
+       struct device           *dev;
+       struct i2c_client       *client;
+
+       /* Output details */
+       u8                      cache_out;
+       struct gpio_chip        chip_out;
+
+       /* Input details */
+       u8                      cache_in;
+       struct gpio_chip        chip_in;
+
+       u16                     irqs_enabled;
+       uint                    irq_start;
+       int                     nirqs;
+
+       /*
+        * Work structure to allow for setting values outside of any
+        * possible interrupt context
+        */
+       struct work_struct set_val_work;
+};
+
+struct htcpld_data {
+       /* irq info */
+       u16                irqs_enabled;
+       uint               irq_start;
+       int                nirqs;
+       uint               chained_irq;
+       unsigned int       int_reset_gpio_hi;
+       unsigned int       int_reset_gpio_lo;
+
+       /* htcpld info */
+       struct htcpld_chip *chip;
+       unsigned int       nchips;
+};
+
+/* There does not appear to be a way to proactively mask interrupts
+ * on the htcpld chip itself.  So, we simply ignore interrupts that
+ * aren't desired. */
+static void htcpld_mask(unsigned int irq)
+{
+       struct htcpld_chip *chip = get_irq_chip_data(irq);
+       chip->irqs_enabled &= ~(1 << (irq - chip->irq_start));
+       pr_debug("HTCPLD mask %d %04x\n", irq, chip->irqs_enabled);
+}
+static void htcpld_unmask(unsigned int irq)
+{
+       struct htcpld_chip *chip = get_irq_chip_data(irq);
+       chip->irqs_enabled |= 1 << (irq - chip->irq_start);
+       pr_debug("HTCPLD unmask %d %04x\n", irq, chip->irqs_enabled);
+}
+
+static int htcpld_set_type(unsigned int irq, unsigned int flags)
+{
+       struct irq_desc *d = irq_to_desc(irq);
+
+       if (!d) {
+               pr_err("HTCPLD invalid IRQ: %d\n", irq);
+               return -EINVAL;
+       }
+
+       if (flags & ~IRQ_TYPE_SENSE_MASK)
+               return -EINVAL;
+
+       /* We only allow edge triggering */
+       if (flags & (IRQ_TYPE_LEVEL_LOW|IRQ_TYPE_LEVEL_HIGH))
+               return -EINVAL;
+
+       d->status &= ~IRQ_TYPE_SENSE_MASK;
+       d->status |= flags;
+
+       return 0;
+}
+
+static struct irq_chip htcpld_muxed_chip = {
+       .name     = "htcpld",
+       .mask     = htcpld_mask,
+       .unmask   = htcpld_unmask,
+       .set_type = htcpld_set_type,
+};
+
+/* To properly dispatch IRQ events, we need to read from the
+ * chip.  This is an I2C action that could possibly sleep
+ * (which is bad in interrupt context) -- so we use a threaded
+ * interrupt handler to get around that.
+ */
+static irqreturn_t htcpld_handler(int irq, void *dev)
+{
+       struct htcpld_data *htcpld = dev;
+       unsigned int i;
+       unsigned long flags;
+       int irqpin;
+       struct irq_desc *desc;
+
+       if (!htcpld) {
+               pr_debug("htcpld is null in ISR\n");
+               return IRQ_HANDLED;
+       }
+
+       /*
+        * For each chip, do a read of the chip and trigger any interrupts
+        * desired.  The interrupts will be triggered from LSB to MSB (i.e.
+        * bit 0 first, then bit 1, etc.)
+        *
+        * For chips that have no interrupt range specified, just skip 'em.
+        */
+       for (i = 0; i < htcpld->nchips; i++) {
+               struct htcpld_chip *chip = &htcpld->chip[i];
+               struct i2c_client *client;
+               int val;
+               unsigned long uval, old_val;
+
+               if (!chip) {
+                       pr_debug("chip %d is null in ISR\n", i);
+                       continue;
+               }
+
+               if (chip->nirqs == 0)
+                       continue;
+
+               client = chip->client;
+               if (!client) {
+                       pr_debug("client %d is null in ISR\n", i);
+                       continue;
+               }
+
+               /* Scan the chip */
+               val = i2c_smbus_read_byte_data(client, chip->cache_out);
+               if (val < 0) {
+                       /* Throw a warning and skip this chip */
+                       dev_warn(chip->dev, "Unable to read from chip: %d\n",
+                                val);
+                       continue;
+               }
+
+               uval = (unsigned long)val;
+
+               spin_lock_irqsave(&chip->lock, flags);
+
+               /* Save away the old value so we can compare it */
+               old_val = chip->cache_in;
+
+               /* Write the new value */
+               chip->cache_in = uval;
+
+               spin_unlock_irqrestore(&chip->lock, flags);
+
+               /*
+                * For each bit in the data (starting at bit 0), trigger
+                * associated interrupts.
+                */
+               for (irqpin = 0; irqpin < chip->nirqs; irqpin++) {
+                       unsigned oldb, newb;
+                       int flags;
+
+                       irq = chip->irq_start + irqpin;
+                       desc = irq_to_desc(irq);
+                       flags = desc->status;
+
+                       /* Run the IRQ handler, but only if the bit value
+                        * changed, and the proper flags are set */
+                       oldb = (old_val >> irqpin) & 1;
+                       newb = (uval >> irqpin) & 1;
+
+                       if ((!oldb && newb && (flags & IRQ_TYPE_EDGE_RISING)) ||
+                           (oldb && !newb &&
+                            (flags & IRQ_TYPE_EDGE_FALLING))) {
+                               pr_debug("fire IRQ %d\n", irqpin);
+                               desc->handle_irq(irq, desc);
+                       }
+               }
+       }
+
+       /*
+        * In order to continue receiving interrupts, the int_reset_gpio must
+        * be asserted.
+        */
+       if (htcpld->int_reset_gpio_hi)
+               gpio_set_value(htcpld->int_reset_gpio_hi, 1);
+       if (htcpld->int_reset_gpio_lo)
+               gpio_set_value(htcpld->int_reset_gpio_lo, 0);
+
+       return IRQ_HANDLED;
+}
+
+/*
+ * The GPIO set routines can be called from interrupt context, especially if,
+ * for example they're attached to the led-gpio framework and a trigger is
+ * enabled.  As such, we declared work above in the htcpld_chip structure,
+ * and that work is scheduled in the set routine.  The kernel can then run
+ * the I2C functions, which will sleep, in process context.
+ */
+void htcpld_chip_set(struct gpio_chip *chip, unsigned offset, int val)
+{
+       struct i2c_client *client;
+       struct htcpld_chip *chip_data;
+       unsigned long flags;
+
+       chip_data = container_of(chip, struct htcpld_chip, chip_out);
+       if (!chip_data)
+               return;
+
+       client = chip_data->client;
+       if (client == NULL)
+               return;
+
+       spin_lock_irqsave(&chip_data->lock, flags);
+       if (val)
+               chip_data->cache_out |= (1 << offset);
+       else
+               chip_data->cache_out &= ~(1 << offset);
+       spin_unlock_irqrestore(&chip_data->lock, flags);
+
+       schedule_work(&(chip_data->set_val_work));
+}
+
+void htcpld_chip_set_ni(struct work_struct *work)
+{
+       struct htcpld_chip *chip_data;
+       struct i2c_client *client;
+
+       chip_data = container_of(work, struct htcpld_chip, set_val_work);
+       client = chip_data->client;
+       i2c_smbus_read_byte_data(client, chip_data->cache_out);
+}
+
+int htcpld_chip_get(struct gpio_chip *chip, unsigned offset)
+{
+       struct htcpld_chip *chip_data;
+       int val = 0;
+       int is_input = 0;
+
+       /* Try out first */
+       chip_data = container_of(chip, struct htcpld_chip, chip_out);
+       if (!chip_data) {
+               /* Try in */
+               is_input = 1;
+               chip_data = container_of(chip, struct htcpld_chip, chip_in);
+               if (!chip_data)
+                       return -EINVAL;
+       }
+
+       /* Determine if this is an input or output GPIO */
+       if (!is_input)
+               /* Use the output cache */
+               val = (chip_data->cache_out >> offset) & 1;
+       else
+               /* Use the input cache */
+               val = (chip_data->cache_in >> offset) & 1;
+
+       if (val)
+               return 1;
+       else
+               return 0;
+}
+
+static int htcpld_direction_output(struct gpio_chip *chip,
+                                       unsigned offset, int value)
+{
+       htcpld_chip_set(chip, offset, value);
+       return 0;
+}
+
+static int htcpld_direction_input(struct gpio_chip *chip,
+                                       unsigned offset)
+{
+       /*
+        * No-op: this function can only be called on the input chip.
+        * We do however make sure the offset is within range.
+        */
+       return (offset < chip->ngpio) ? 0 : -EINVAL;
+}
+
+int htcpld_chip_to_irq(struct gpio_chip *chip, unsigned offset)
+{
+       struct htcpld_chip *chip_data;
+
+       chip_data = container_of(chip, struct htcpld_chip, chip_in);
+
+       if (offset < chip_data->nirqs)
+               return chip_data->irq_start + offset;
+       else
+               return -EINVAL;
+}
+
+void htcpld_chip_reset(struct i2c_client *client)
+{
+       struct htcpld_chip *chip_data = i2c_get_clientdata(client);
+       if (!chip_data)
+               return;
+
+       i2c_smbus_read_byte_data(
+               client, (chip_data->cache_out = chip_data->reset));
+}
+
+static int __devinit htcpld_setup_chip_irq(
+               struct platform_device *pdev,
+               int chip_index)
+{
+       struct htcpld_data *htcpld;
+       struct device *dev = &pdev->dev;
+       struct htcpld_core_platform_data *pdata;
+       struct htcpld_chip *chip;
+       struct htcpld_chip_platform_data *plat_chip_data;
+       unsigned int irq, irq_end;
+       int ret = 0;
+
+       /* Get the platform and driver data */
+       pdata = dev->platform_data;
+       htcpld = platform_get_drvdata(pdev);
+       chip = &htcpld->chip[chip_index];
+       plat_chip_data = &pdata->chip[chip_index];
+
+       /* Setup irq handlers */
+       irq_end = chip->irq_start + chip->nirqs;
+       for (irq = chip->irq_start; irq < irq_end; irq++) {
+               set_irq_chip(irq, &htcpld_muxed_chip);
+               set_irq_chip_data(irq, chip);
+               set_irq_handler(irq, handle_simple_irq);
+#ifdef CONFIG_ARM
+               set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+#else
+               set_irq_probe(irq);
+#endif
+       }
+
+       return ret;
+}
+
+static int __devinit htcpld_register_chip_i2c(
+               struct platform_device *pdev,
+               int chip_index)
+{
+       struct htcpld_data *htcpld;
+       struct device *dev = &pdev->dev;
+       struct htcpld_core_platform_data *pdata;
+       struct htcpld_chip *chip;
+       struct htcpld_chip_platform_data *plat_chip_data;
+       struct i2c_adapter *adapter;
+       struct i2c_client *client;
+       struct i2c_board_info info;
+
+       /* Get the platform and driver data */
+       pdata = dev->platform_data;
+       htcpld = platform_get_drvdata(pdev);
+       chip = &htcpld->chip[chip_index];
+       plat_chip_data = &pdata->chip[chip_index];
+
+       adapter = i2c_get_adapter(pdata->i2c_adapter_id);
+       if (adapter == NULL) {
+               /* Eek, no such I2C adapter!  Bail out. */
+               dev_warn(dev, "Chip at i2c address 0x%x: Invalid i2c adapter %d\n",
+                        plat_chip_data->addr, pdata->i2c_adapter_id);
+               return -ENODEV;
+       }
+
+       if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_READ_BYTE_DATA)) {
+               dev_warn(dev, "i2c adapter %d non-functional\n",
+                        pdata->i2c_adapter_id);
+               return -EINVAL;
+       }
+
+       memset(&info, 0, sizeof(struct i2c_board_info));
+       info.addr = plat_chip_data->addr;
+       strlcpy(info.type, "htcpld-chip", I2C_NAME_SIZE);
+       info.platform_data = chip;
+
+       /* Add the I2C device.  This calls the probe() function. */
+       client = i2c_new_device(adapter, &info);
+       if (!client) {
+               /* I2C device registration failed, contineu with the next */
+               dev_warn(dev, "Unable to add I2C device for 0x%x\n",
+                        plat_chip_data->addr);
+               return -ENODEV;
+       }
+
+       i2c_set_clientdata(client, chip);
+       snprintf(client->name, I2C_NAME_SIZE, "Chip_0x%d", client->addr);
+       chip->client = client;
+
+       /* Reset the chip */
+       htcpld_chip_reset(client);
+       chip->cache_in = i2c_smbus_read_byte_data(client, chip->cache_out);
+
+       return 0;
+}
+
+static void __devinit htcpld_unregister_chip_i2c(
+               struct platform_device *pdev,
+               int chip_index)
+{
+       struct htcpld_data *htcpld;
+       struct htcpld_chip *chip;
+
+       /* Get the platform and driver data */
+       htcpld = platform_get_drvdata(pdev);
+       chip = &htcpld->chip[chip_index];
+
+       if (chip->client)
+               i2c_unregister_device(chip->client);
+}
+
+static int __devinit htcpld_register_chip_gpio(
+               struct platform_device *pdev,
+               int chip_index)
+{
+       struct htcpld_data *htcpld;
+       struct device *dev = &pdev->dev;
+       struct htcpld_core_platform_data *pdata;
+       struct htcpld_chip *chip;
+       struct htcpld_chip_platform_data *plat_chip_data;
+       struct gpio_chip *gpio_chip;
+       int ret = 0;
+
+       /* Get the platform and driver data */
+       pdata = dev->platform_data;
+       htcpld = platform_get_drvdata(pdev);
+       chip = &htcpld->chip[chip_index];
+       plat_chip_data = &pdata->chip[chip_index];
+
+       /* Setup the GPIO chips */
+       gpio_chip = &(chip->chip_out);
+       gpio_chip->label           = "htcpld-out";
+       gpio_chip->dev             = dev;
+       gpio_chip->owner           = THIS_MODULE;
+       gpio_chip->get             = htcpld_chip_get;
+       gpio_chip->set             = htcpld_chip_set;
+       gpio_chip->direction_input = NULL;
+       gpio_chip->direction_output = htcpld_direction_output;
+       gpio_chip->base            = plat_chip_data->gpio_out_base;
+       gpio_chip->ngpio           = plat_chip_data->num_gpios;
+
+       gpio_chip = &(chip->chip_in);
+       gpio_chip->label           = "htcpld-in";
+       gpio_chip->dev             = dev;
+       gpio_chip->owner           = THIS_MODULE;
+       gpio_chip->get             = htcpld_chip_get;
+       gpio_chip->set             = NULL;
+       gpio_chip->direction_input = htcpld_direction_input;
+       gpio_chip->direction_output = NULL;
+       gpio_chip->to_irq          = htcpld_chip_to_irq;
+       gpio_chip->base            = plat_chip_data->gpio_in_base;
+       gpio_chip->ngpio           = plat_chip_data->num_gpios;
+
+       /* Add the GPIO chips */
+       ret = gpiochip_add(&(chip->chip_out));
+       if (ret) {
+               dev_warn(dev, "Unable to register output GPIOs for 0x%x: %d\n",
+                        plat_chip_data->addr, ret);
+               return ret;
+       }
+
+       ret = gpiochip_add(&(chip->chip_in));
+       if (ret) {
+               int error;
+
+               dev_warn(dev, "Unable to register input GPIOs for 0x%x: %d\n",
+                        plat_chip_data->addr, ret);
+
+               error = gpiochip_remove(&(chip->chip_out));
+               if (error)
+                       dev_warn(dev, "Error while trying to unregister gpio chip: %d\n", error);
+
+               return ret;
+       }
+
+       return 0;
+}
+
+static int __devinit htcpld_setup_chips(struct platform_device *pdev)
+{
+       struct htcpld_data *htcpld;
+       struct device *dev = &pdev->dev;
+       struct htcpld_core_platform_data *pdata;
+       int i;
+
+       /* Get the platform and driver data */
+       pdata = dev->platform_data;
+       htcpld = platform_get_drvdata(pdev);
+
+       /* Setup each chip's output GPIOs */
+       htcpld->nchips = pdata->num_chip;
+       htcpld->chip = kzalloc(sizeof(struct htcpld_chip) * htcpld->nchips,
+                              GFP_KERNEL);
+       if (!htcpld->chip) {
+               dev_warn(dev, "Unable to allocate memory for chips\n");
+               return -ENOMEM;
+       }
+
+       /* Add the chips as best we can */
+       for (i = 0; i < htcpld->nchips; i++) {
+               int ret;
+
+               /* Setup the HTCPLD chips */
+               htcpld->chip[i].reset = pdata->chip[i].reset;
+               htcpld->chip[i].cache_out = pdata->chip[i].reset;
+               htcpld->chip[i].cache_in = 0;
+               htcpld->chip[i].dev = dev;
+               htcpld->chip[i].irq_start = pdata->chip[i].irq_base;
+               htcpld->chip[i].nirqs = pdata->chip[i].num_irqs;
+
+               INIT_WORK(&(htcpld->chip[i].set_val_work), &htcpld_chip_set_ni);
+               spin_lock_init(&(htcpld->chip[i].lock));
+
+               /* Setup the interrupts for the chip */
+               if (htcpld->chained_irq) {
+                       ret = htcpld_setup_chip_irq(pdev, i);
+                       if (ret)
+                               continue;
+               }
+
+               /* Register the chip with I2C */
+               ret = htcpld_register_chip_i2c(pdev, i);
+               if (ret)
+                       continue;
+
+
+               /* Register the chips with the GPIO subsystem */
+               ret = htcpld_register_chip_gpio(pdev, i);
+               if (ret) {
+                       /* Unregister the chip from i2c and continue */
+                       htcpld_unregister_chip_i2c(pdev, i);
+                       continue;
+               }
+
+               dev_info(dev, "Registered chip at 0x%x\n", pdata->chip[i].addr);
+       }
+
+       return 0;
+}
+
+static int __devinit htcpld_core_probe(struct platform_device *pdev)
+{
+       struct htcpld_data *htcpld;
+       struct device *dev = &pdev->dev;
+       struct htcpld_core_platform_data *pdata;
+       struct resource *res;
+       int ret = 0;
+
+       if (!dev)
+               return -ENODEV;
+
+       pdata = dev->platform_data;
+       if (!pdata) {
+               dev_warn(dev, "Platform data not found for htcpld core!\n");
+               return -ENXIO;
+       }
+
+       htcpld = kzalloc(sizeof(struct htcpld_data), GFP_KERNEL);
+       if (!htcpld)
+               return -ENOMEM;
+
+       /* Find chained irq */
+       ret = -EINVAL;
+       res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
+       if (res) {
+               int flags;
+               htcpld->chained_irq = res->start;
+
+               /* Setup the chained interrupt handler */
+               flags = IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING;
+               ret = request_threaded_irq(htcpld->chained_irq,
+                                          NULL, htcpld_handler,
+                                          flags, pdev->name, htcpld);
+               if (ret) {
+                       dev_warn(dev, "Unable to setup chained irq handler: %d\n", ret);
+                       goto fail;
+               } else
+                       device_init_wakeup(dev, 0);
+       }
+
+       /* Set the driver data */
+       platform_set_drvdata(pdev, htcpld);
+
+       /* Setup the htcpld chips */
+       ret = htcpld_setup_chips(pdev);
+       if (ret)
+               goto fail;
+
+       /* Request the GPIO(s) for the int reset and set them up */
+       if (pdata->int_reset_gpio_hi) {
+               ret = gpio_request(pdata->int_reset_gpio_hi, "htcpld-core");
+               if (ret) {
+                       /*
+                        * If it failed, that sucks, but we can probably
+                        * continue on without it.
+                        */
+                       dev_warn(dev, "Unable to request int_reset_gpio_hi -- interrupts may not work\n");
+                       htcpld->int_reset_gpio_hi = 0;
+               } else {
+                       htcpld->int_reset_gpio_hi = pdata->int_reset_gpio_hi;
+                       gpio_set_value(htcpld->int_reset_gpio_hi, 1);
+               }
+       }
+
+       if (pdata->int_reset_gpio_lo) {
+               ret = gpio_request(pdata->int_reset_gpio_lo, "htcpld-core");
+               if (ret) {
+                       /*
+                        * If it failed, that sucks, but we can probably
+                        * continue on without it.
+                        */
+                       dev_warn(dev, "Unable to request int_reset_gpio_lo -- interrupts may not work\n");
+                       htcpld->int_reset_gpio_lo = 0;
+               } else {
+                       htcpld->int_reset_gpio_lo = pdata->int_reset_gpio_lo;
+                       gpio_set_value(htcpld->int_reset_gpio_lo, 0);
+               }
+       }
+
+       dev_info(dev, "Initialized successfully\n");
+       return 0;
+
+fail:
+       kfree(htcpld);
+       return ret;
+}
+
+/* The I2C Driver -- used internally */
+static const struct i2c_device_id htcpld_chip_id[] = {
+       { "htcpld-chip", 0 },
+       { }
+};
+MODULE_DEVICE_TABLE(i2c, htcpld_chip_id);
+
+
+static struct i2c_driver htcpld_chip_driver = {
+       .driver = {
+               .name   = "htcpld-chip",
+       },
+       .id_table = htcpld_chip_id,
+};
+
+/* The Core Driver */
+static struct platform_driver htcpld_core_driver = {
+       .driver = {
+               .name = "i2c-htcpld",
+       },
+};
+
+static int __init htcpld_core_init(void)
+{
+       int ret;
+
+       /* Register the I2C Chip driver */
+       ret = i2c_add_driver(&htcpld_chip_driver);
+       if (ret)
+               return ret;
+
+       /* Probe for our chips */
+       return platform_driver_probe(&htcpld_core_driver, htcpld_core_probe);
+}
+
+static void __exit htcpld_core_exit(void)
+{
+       i2c_del_driver(&htcpld_chip_driver);
+       platform_driver_unregister(&htcpld_core_driver);
+}
+
+module_init(htcpld_core_init);
+module_exit(htcpld_core_exit);
+
+MODULE_AUTHOR("Cory Maccarrone <darkstar6262@gmail.com>");
+MODULE_DESCRIPTION("I2C HTC PLD Driver");
+MODULE_LICENSE("GPL");
+
diff --git a/include/linux/htcpld.h b/include/linux/htcpld.h
new file mode 100644 (file)
index 0000000..ab3f6cb
--- /dev/null
@@ -0,0 +1,24 @@
+#ifndef __LINUX_HTCPLD_H
+#define __LINUX_HTCPLD_H
+
+struct htcpld_chip_platform_data {
+       unsigned int addr;
+       unsigned int reset;
+       unsigned int num_gpios;
+       unsigned int gpio_out_base;
+       unsigned int gpio_in_base;
+       unsigned int irq_base;
+       unsigned int num_irqs;
+};
+
+struct htcpld_core_platform_data {
+       unsigned int                      int_reset_gpio_hi;
+       unsigned int                      int_reset_gpio_lo;
+       unsigned int                      i2c_adapter_id;
+
+       struct htcpld_chip_platform_data  *chip;
+       unsigned int                      num_chip;
+};
+
+#endif /* __LINUX_HTCPLD_H */
+