linux-imx

/*

 *  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/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>

#include <linux/slab.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;

​

    unsigned int        flow_type;

    /*

     * 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(struct irq_data *data)

{

    struct htcpld_chip *chip = irq_data_get_irq_chip_data(data);

    chip->irqs_enabled &= ~(1 << (data->irq - chip->irq_start));

    pr_debug("HTCPLD mask %d %04x\n", data->irq, chip->irqs_enabled);

}

static void htcpld_unmask(struct irq_data *data)

{