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Release 4.11 drivers/gpio/gpio-mc33880.c

Directory: drivers/gpio
/*
 * MC33880 high-side/low-side switch GPIO driver
 * Copyright (c) 2009 Intel Corporation
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * 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.
 */

/* Supports:
 * Freescale MC33880 high-side/low-side switch
 */

#include <linux/init.h>
#include <linux/mutex.h>
#include <linux/spi/spi.h>
#include <linux/spi/mc33880.h>
#include <linux/gpio.h>
#include <linux/slab.h>
#include <linux/module.h>


#define DRIVER_NAME "mc33880"

/*
 * Pin configurations, see MAX7301 datasheet page 6
 */

#define PIN_CONFIG_MASK 0x03

#define PIN_CONFIG_IN_PULLUP 0x03

#define PIN_CONFIG_IN_WO_PULLUP 0x02

#define PIN_CONFIG_OUT 0x01


#define PIN_NUMBER 8


/*
 * Some registers must be read back to modify.
 * To save time we cache them here in memory
 */

struct mc33880 {
	
struct mutex	lock;	/* protect from simultaneous accesses */
	
u8		port_config;
	
struct gpio_chip chip;
	
struct spi_device *spi;
};


static int mc33880_write_config(struct mc33880 *mc) { return spi_write(mc->spi, &mc->port_config, sizeof(mc->port_config)); }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors31100.00%1100.00%
Total31100.00%1100.00%


static int __mc33880_set(struct mc33880 *mc, unsigned offset, int value) { if (value) mc->port_config |= 1 << offset; else mc->port_config &= ~(1 << offset); return mc33880_write_config(mc); }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors47100.00%1100.00%
Total47100.00%1100.00%


static void mc33880_set(struct gpio_chip *chip, unsigned offset, int value) { struct mc33880 *mc = gpiochip_get_data(chip); mutex_lock(&mc->lock); __mc33880_set(mc, offset, value); mutex_unlock(&mc->lock); }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors5198.08%150.00%
Linus Walleij11.92%150.00%
Total52100.00%2100.00%


static int mc33880_probe(struct spi_device *spi) { struct mc33880 *mc; struct mc33880_platform_data *pdata; int ret; pdata = dev_get_platdata(&spi->dev); if (!pdata || !pdata->base) { dev_dbg(&spi->dev, "incorrect or missing platform data\n"); return -EINVAL; } /* * bits_per_word cannot be configured in platform data */ spi->bits_per_word = 8; ret = spi_setup(spi); if (ret < 0) return ret; mc = devm_kzalloc(&spi->dev, sizeof(struct mc33880), GFP_KERNEL); if (!mc) return -ENOMEM; mutex_init(&mc->lock); spi_set_drvdata(spi, mc); mc->spi = spi; mc->chip.label = DRIVER_NAME, mc->chip.set = mc33880_set; mc->chip.base = pdata->base; mc->chip.ngpio = PIN_NUMBER; mc->chip.can_sleep = true; mc->chip.parent = &spi->dev; mc->chip.owner = THIS_MODULE; mc->port_config = 0x00; /* write twice, because during initialisation the first setting * is just for testing SPI communication, and the second is the * "real" configuration */ ret = mc33880_write_config(mc); mc->port_config = 0x00; if (!ret) ret = mc33880_write_config(mc); if (ret) { dev_err(&spi->dev, "Failed writing to " DRIVER_NAME ": %d\n", ret); goto exit_destroy; } ret = gpiochip_add_data(&mc->chip, mc); if (ret) goto exit_destroy; return ret; exit_destroy: mutex_destroy(&mc->lock); return ret; }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors26092.20%112.50%
Jingoo Han176.03%450.00%
Linus Walleij51.77%337.50%
Total282100.00%8100.00%


static int mc33880_remove(struct spi_device *spi) { struct mc33880 *mc; mc = spi_get_drvdata(spi); if (!mc) return -ENODEV; gpiochip_remove(&mc->chip); mutex_destroy(&mc->lock); return 0; }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors4894.12%125.00%
Jingoo Han11.96%125.00%
abdoulaye berthe11.96%125.00%
Varka Bhadram11.96%125.00%
Total51100.00%4100.00%

static struct spi_driver mc33880_driver = { .driver = { .name = DRIVER_NAME, }, .probe = mc33880_probe, .remove = mc33880_remove, };
static int __init mc33880_init(void) { return spi_register_driver(&mc33880_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors16100.00%1100.00%
Total16100.00%1100.00%

/* register after spi postcore initcall and before * subsys initcalls that may rely on these GPIOs */ subsys_initcall(mc33880_init);
static void __exit mc33880_exit(void) { spi_unregister_driver(&mc33880_driver); }

Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors15100.00%1100.00%
Total15100.00%1100.00%

module_exit(mc33880_exit); MODULE_AUTHOR("Mocean Laboratories <info@mocean-labs.com>"); MODULE_LICENSE("GPL v2");

Overall Contributors

PersonTokensPropCommitsCommitProp
Richard Röjfors57994.45%17.14%
Jingoo Han182.94%428.57%
Linus Walleij60.98%321.43%
Paul Gortmaker30.49%17.14%
Tejun Heo30.49%17.14%
Lucas De Marchi10.16%17.14%
abdoulaye berthe10.16%17.14%
Grant C. Likely10.16%17.14%
Varka Bhadram10.16%17.14%
Total613100.00%14100.00%
Directory: drivers/gpio
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