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	gpio: Add GPIO Aggregator
GPIO controllers are exported to userspace using /dev/gpiochip*
character devices.  Access control to these devices is provided by
standard UNIX file system permissions, on an all-or-nothing basis:
either a GPIO controller is accessible for a user, or it is not.
Currently no mechanism exists to control access to individual GPIOs.
Hence add a GPIO driver to aggregate existing GPIOs, and expose them as
a new gpiochip.
This supports the following use cases:
  - Aggregating GPIOs using Sysfs
    This is useful for implementing access control, and assigning a set
    of GPIOs to a specific user or virtual machine.
  - Generic GPIO Driver
    This is useful for industrial control, where it can provide
    userspace access to a simple GPIO-operated device described in DT,
    cfr. e.g. spidev for SPI-operated devices.
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Tested-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Reviewed-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Link: https://lore.kernel.org/r/20200511145257.22970-5-geert+renesas@glider.be
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
			
			
This commit is contained in:
		
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						commit
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					 3 changed files with 581 additions and 0 deletions
				
			
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			@ -1541,6 +1541,18 @@ config GPIO_VIPERBOARD
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endmenu
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config GPIO_AGGREGATOR
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	tristate "GPIO Aggregator"
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	help
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	  Say yes here to enable the GPIO Aggregator, which provides a way to
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	  aggregate existing GPIO lines into a new virtual GPIO chip.
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	  This can serve the following purposes:
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	    - Assign permissions for a collection of GPIO lines to a user,
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	    - Export a collection of GPIO lines to a virtual machine,
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	    - Provide a generic driver for a GPIO-operated device in an
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	      industrial control context, to be operated from userspace using
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	      the GPIO chardev interface.
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config GPIO_MOCKUP
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	tristate "GPIO Testing Driver"
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	select IRQ_SIM
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			@ -25,6 +25,7 @@ obj-$(CONFIG_GPIO_74XX_MMIO)		+= gpio-74xx-mmio.o
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obj-$(CONFIG_GPIO_ADNP)			+= gpio-adnp.o
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obj-$(CONFIG_GPIO_ADP5520)		+= gpio-adp5520.o
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obj-$(CONFIG_GPIO_ADP5588)		+= gpio-adp5588.o
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obj-$(CONFIG_GPIO_AGGREGATOR)		+= gpio-aggregator.o
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obj-$(CONFIG_GPIO_ALTERA_A10SR)		+= gpio-altera-a10sr.o
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obj-$(CONFIG_GPIO_ALTERA)  		+= gpio-altera.o
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obj-$(CONFIG_GPIO_AMD8111)		+= gpio-amd8111.o
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						 | 
				
			
			
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		|||
							
								
								
									
										568
									
								
								drivers/gpio/gpio-aggregator.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										568
									
								
								drivers/gpio/gpio-aggregator.c
									
									
									
									
									
										Normal file
									
								
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			@ -0,0 +1,568 @@
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// SPDX-License-Identifier: GPL-2.0-only
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//
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// GPIO Aggregator
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//
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// Copyright (C) 2019-2020 Glider bv
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#define DRV_NAME       "gpio-aggregator"
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#define pr_fmt(fmt)	DRV_NAME ": " fmt
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#include <linux/bitmap.h>
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#include <linux/bitops.h>
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#include <linux/ctype.h>
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#include <linux/gpio/consumer.h>
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#include <linux/gpio/driver.h>
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#include <linux/gpio/machine.h>
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#include <linux/idr.h>
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#include <linux/kernel.h>
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#include <linux/module.h>
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#include <linux/mutex.h>
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#include <linux/overflow.h>
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#include <linux/platform_device.h>
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#include <linux/spinlock.h>
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#include <linux/string.h>
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/*
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 * GPIO Aggregator sysfs interface
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 */
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struct gpio_aggregator {
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	struct gpiod_lookup_table *lookups;
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	struct platform_device *pdev;
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	char args[];
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};
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static DEFINE_MUTEX(gpio_aggregator_lock);	/* protects idr */
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static DEFINE_IDR(gpio_aggregator_idr);
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static char *get_arg(char **args)
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{
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	char *start = *args, *end;
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	start = skip_spaces(start);
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	if (!*start)
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		return NULL;
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	if (*start == '"') {
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		/* Quoted arg */
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		end = strchr(++start, '"');
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		if (!end)
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			return ERR_PTR(-EINVAL);
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	} else {
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		/* Unquoted arg */
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		for (end = start; *end && !isspace(*end); end++) ;
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	}
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	if (*end)
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		*end++ = '\0';
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	*args = end;
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	return start;
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}
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static bool isrange(const char *s)
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{
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	size_t n;
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	if (IS_ERR_OR_NULL(s))
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		return false;
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	while (1) {
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		n = strspn(s, "0123456789");
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		if (!n)
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			return false;
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		s += n;
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		switch (*s++) {
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		case '\0':
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			return true;
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		case '-':
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		case ',':
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			break;
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		default:
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			return false;
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		}
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	}
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}
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static int aggr_add_gpio(struct gpio_aggregator *aggr, const char *key,
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			 int hwnum, unsigned int *n)
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{
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	struct gpiod_lookup_table *lookups;
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	lookups = krealloc(aggr->lookups, struct_size(lookups, table, *n + 2),
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			   GFP_KERNEL);
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	if (!lookups)
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		return -ENOMEM;
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	lookups->table[*n] =
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		(struct gpiod_lookup)GPIO_LOOKUP_IDX(key, hwnum, NULL, *n, 0);
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	(*n)++;
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	memset(&lookups->table[*n], 0, sizeof(lookups->table[*n]));
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	aggr->lookups = lookups;
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	return 0;
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}
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static int aggr_parse(struct gpio_aggregator *aggr)
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{
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	unsigned int first_index, last_index, i, n = 0;
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	char *name, *offsets, *first, *last, *next;
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	char *args = aggr->args;
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	int error;
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	for (name = get_arg(&args), offsets = get_arg(&args); name;
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	     offsets = get_arg(&args)) {
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		if (IS_ERR(name)) {
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			pr_err("Cannot get GPIO specifier: %pe\n", name);
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			return PTR_ERR(name);
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		}
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		if (!isrange(offsets)) {
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			/* Named GPIO line */
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			error = aggr_add_gpio(aggr, name, U16_MAX, &n);
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			if (error)
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				return error;
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			name = offsets;
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			continue;
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		}
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		/* GPIO chip + offset(s) */
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		for (first = offsets; *first; first = next) {
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			next = strchrnul(first, ',');
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			if (*next)
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				*next++ = '\0';
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			last = strchr(first, '-');
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			if (last)
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				*last++ = '\0';
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			if (kstrtouint(first, 10, &first_index)) {
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				pr_err("Cannot parse GPIO index %s\n", first);
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				return -EINVAL;
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			}
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			if (!last) {
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				last_index = first_index;
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			} else if (kstrtouint(last, 10, &last_index)) {
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				pr_err("Cannot parse GPIO index %s\n", last);
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				return -EINVAL;
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			}
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			for (i = first_index; i <= last_index; i++) {
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				error = aggr_add_gpio(aggr, name, i, &n);
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				if (error)
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					return error;
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			}
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		}
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		name = get_arg(&args);
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	}
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	if (!n) {
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		pr_err("No GPIOs specified\n");
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		return -EINVAL;
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	}
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	return 0;
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}
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static ssize_t new_device_store(struct device_driver *driver, const char *buf,
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				size_t count)
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{
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	struct gpio_aggregator *aggr;
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	struct platform_device *pdev;
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	int res, id;
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	/* kernfs guarantees string termination, so count + 1 is safe */
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	aggr = kzalloc(sizeof(*aggr) + count + 1, GFP_KERNEL);
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	if (!aggr)
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		return -ENOMEM;
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	memcpy(aggr->args, buf, count + 1);
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	aggr->lookups = kzalloc(struct_size(aggr->lookups, table, 1),
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				GFP_KERNEL);
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	if (!aggr->lookups) {
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		res = -ENOMEM;
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		goto free_ga;
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	}
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	mutex_lock(&gpio_aggregator_lock);
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	id = idr_alloc(&gpio_aggregator_idr, aggr, 0, 0, GFP_KERNEL);
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	mutex_unlock(&gpio_aggregator_lock);
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	if (id < 0) {
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		res = id;
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		goto free_table;
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	}
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	aggr->lookups->dev_id = kasprintf(GFP_KERNEL, "%s.%d", DRV_NAME, id);
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	if (!aggr->lookups->dev_id) {
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		res = -ENOMEM;
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		goto remove_idr;
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	}
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	res = aggr_parse(aggr);
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	if (res)
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		goto free_dev_id;
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	gpiod_add_lookup_table(aggr->lookups);
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	pdev = platform_device_register_simple(DRV_NAME, id, NULL, 0);
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	if (IS_ERR(pdev)) {
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		res = PTR_ERR(pdev);
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		goto remove_table;
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	}
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	aggr->pdev = pdev;
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	return count;
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remove_table:
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	gpiod_remove_lookup_table(aggr->lookups);
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free_dev_id:
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	kfree(aggr->lookups->dev_id);
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remove_idr:
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	mutex_lock(&gpio_aggregator_lock);
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	idr_remove(&gpio_aggregator_idr, id);
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	mutex_unlock(&gpio_aggregator_lock);
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free_table:
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	kfree(aggr->lookups);
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free_ga:
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	kfree(aggr);
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	return res;
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}
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static DRIVER_ATTR_WO(new_device);
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static void gpio_aggregator_free(struct gpio_aggregator *aggr)
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{
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	platform_device_unregister(aggr->pdev);
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	gpiod_remove_lookup_table(aggr->lookups);
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	kfree(aggr->lookups->dev_id);
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	kfree(aggr->lookups);
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	kfree(aggr);
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}
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static ssize_t delete_device_store(struct device_driver *driver,
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				   const char *buf, size_t count)
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{
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	struct gpio_aggregator *aggr;
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	unsigned int id;
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	int error;
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	if (!str_has_prefix(buf, DRV_NAME "."))
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		return -EINVAL;
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	error = kstrtouint(buf + strlen(DRV_NAME "."), 10, &id);
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	if (error)
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		return error;
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	mutex_lock(&gpio_aggregator_lock);
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	aggr = idr_remove(&gpio_aggregator_idr, id);
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	mutex_unlock(&gpio_aggregator_lock);
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	if (!aggr)
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		return -ENOENT;
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	gpio_aggregator_free(aggr);
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	return count;
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}
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static DRIVER_ATTR_WO(delete_device);
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static struct attribute *gpio_aggregator_attrs[] = {
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	&driver_attr_new_device.attr,
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	&driver_attr_delete_device.attr,
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	NULL,
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};
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ATTRIBUTE_GROUPS(gpio_aggregator);
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static int __exit gpio_aggregator_idr_remove(int id, void *p, void *data)
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{
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	gpio_aggregator_free(p);
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	return 0;
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}
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static void __exit gpio_aggregator_remove_all(void)
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{
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	mutex_lock(&gpio_aggregator_lock);
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	idr_for_each(&gpio_aggregator_idr, gpio_aggregator_idr_remove, NULL);
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	idr_destroy(&gpio_aggregator_idr);
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	mutex_unlock(&gpio_aggregator_lock);
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}
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/*
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 *  GPIO Forwarder
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 */
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struct gpiochip_fwd {
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	struct gpio_chip chip;
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	struct gpio_desc **descs;
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	union {
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		struct mutex mlock;	/* protects tmp[] if can_sleep */
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		spinlock_t slock;	/* protects tmp[] if !can_sleep */
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	};
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	unsigned long tmp[];		/* values and descs for multiple ops */
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};
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static int gpio_fwd_get_direction(struct gpio_chip *chip, unsigned int offset)
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{
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	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
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	return gpiod_get_direction(fwd->descs[offset]);
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}
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static int gpio_fwd_direction_input(struct gpio_chip *chip, unsigned int offset)
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{
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	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
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	return gpiod_direction_input(fwd->descs[offset]);
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}
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static int gpio_fwd_direction_output(struct gpio_chip *chip,
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				     unsigned int offset, int value)
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{
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	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
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	return gpiod_direction_output(fwd->descs[offset], value);
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}
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static int gpio_fwd_get(struct gpio_chip *chip, unsigned int offset)
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{
 | 
			
		||||
	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 | 
			
		||||
 | 
			
		||||
	return gpiod_get_value(fwd->descs[offset]);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int gpio_fwd_get_multiple(struct gpio_chip *chip, unsigned long *mask,
 | 
			
		||||
				 unsigned long *bits)
 | 
			
		||||
{
 | 
			
		||||
	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 | 
			
		||||
	unsigned long *values, flags = 0;
 | 
			
		||||
	struct gpio_desc **descs;
 | 
			
		||||
	unsigned int i, j = 0;
 | 
			
		||||
	int error;
 | 
			
		||||
 | 
			
		||||
	if (chip->can_sleep)
 | 
			
		||||
		mutex_lock(&fwd->mlock);
 | 
			
		||||
	else
 | 
			
		||||
		spin_lock_irqsave(&fwd->slock, flags);
 | 
			
		||||
 | 
			
		||||
	/* Both values bitmap and desc pointers are stored in tmp[] */
 | 
			
		||||
	values = &fwd->tmp[0];
 | 
			
		||||
	descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
 | 
			
		||||
 | 
			
		||||
	bitmap_clear(values, 0, fwd->chip.ngpio);
 | 
			
		||||
	for_each_set_bit(i, mask, fwd->chip.ngpio)
 | 
			
		||||
		descs[j++] = fwd->descs[i];
 | 
			
		||||
 | 
			
		||||
	error = gpiod_get_array_value(j, descs, NULL, values);
 | 
			
		||||
	if (!error) {
 | 
			
		||||
		j = 0;
 | 
			
		||||
		for_each_set_bit(i, mask, fwd->chip.ngpio)
 | 
			
		||||
			__assign_bit(i, bits, test_bit(j++, values));
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (chip->can_sleep)
 | 
			
		||||
		mutex_unlock(&fwd->mlock);
 | 
			
		||||
	else
 | 
			
		||||
		spin_unlock_irqrestore(&fwd->slock, flags);
 | 
			
		||||
 | 
			
		||||
	return error;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static void gpio_fwd_set(struct gpio_chip *chip, unsigned int offset, int value)
 | 
			
		||||
{
 | 
			
		||||
	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 | 
			
		||||
 | 
			
		||||
	gpiod_set_value(fwd->descs[offset], value);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static void gpio_fwd_set_multiple(struct gpio_chip *chip, unsigned long *mask,
 | 
			
		||||
				  unsigned long *bits)
 | 
			
		||||
{
 | 
			
		||||
	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 | 
			
		||||
	unsigned long *values, flags = 0;
 | 
			
		||||
	struct gpio_desc **descs;
 | 
			
		||||
	unsigned int i, j = 0;
 | 
			
		||||
 | 
			
		||||
	if (chip->can_sleep)
 | 
			
		||||
		mutex_lock(&fwd->mlock);
 | 
			
		||||
	else
 | 
			
		||||
		spin_lock_irqsave(&fwd->slock, flags);
 | 
			
		||||
 | 
			
		||||
	/* Both values bitmap and desc pointers are stored in tmp[] */
 | 
			
		||||
	values = &fwd->tmp[0];
 | 
			
		||||
	descs = (void *)&fwd->tmp[BITS_TO_LONGS(fwd->chip.ngpio)];
 | 
			
		||||
 | 
			
		||||
	for_each_set_bit(i, mask, fwd->chip.ngpio) {
 | 
			
		||||
		__assign_bit(j, values, test_bit(i, bits));
 | 
			
		||||
		descs[j++] = fwd->descs[i];
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	gpiod_set_array_value(j, descs, NULL, values);
 | 
			
		||||
 | 
			
		||||
	if (chip->can_sleep)
 | 
			
		||||
		mutex_unlock(&fwd->mlock);
 | 
			
		||||
	else
 | 
			
		||||
		spin_unlock_irqrestore(&fwd->slock, flags);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int gpio_fwd_set_config(struct gpio_chip *chip, unsigned int offset,
 | 
			
		||||
			       unsigned long config)
 | 
			
		||||
{
 | 
			
		||||
	struct gpiochip_fwd *fwd = gpiochip_get_data(chip);
 | 
			
		||||
 | 
			
		||||
	return gpiod_set_config(fwd->descs[offset], config);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
 * gpiochip_fwd_create() - Create a new GPIO forwarder
 | 
			
		||||
 * @dev: Parent device pointer
 | 
			
		||||
 * @ngpios: Number of GPIOs in the forwarder.
 | 
			
		||||
 * @descs: Array containing the GPIO descriptors to forward to.
 | 
			
		||||
 *         This array must contain @ngpios entries, and must not be deallocated
 | 
			
		||||
 *         before the forwarder has been destroyed again.
 | 
			
		||||
 *
 | 
			
		||||
 * This function creates a new gpiochip, which forwards all GPIO operations to
 | 
			
		||||
 * the passed GPIO descriptors.
 | 
			
		||||
 *
 | 
			
		||||
 * Return: An opaque object pointer, or an ERR_PTR()-encoded negative error
 | 
			
		||||
 *         code on failure.
 | 
			
		||||
 */
 | 
			
		||||
static struct gpiochip_fwd *gpiochip_fwd_create(struct device *dev,
 | 
			
		||||
						unsigned int ngpios,
 | 
			
		||||
						struct gpio_desc *descs[])
 | 
			
		||||
{
 | 
			
		||||
	const char *label = dev_name(dev);
 | 
			
		||||
	struct gpiochip_fwd *fwd;
 | 
			
		||||
	struct gpio_chip *chip;
 | 
			
		||||
	unsigned int i;
 | 
			
		||||
	int error;
 | 
			
		||||
 | 
			
		||||
	fwd = devm_kzalloc(dev, struct_size(fwd, tmp,
 | 
			
		||||
			   BITS_TO_LONGS(ngpios) + ngpios), GFP_KERNEL);
 | 
			
		||||
	if (!fwd)
 | 
			
		||||
		return ERR_PTR(-ENOMEM);
 | 
			
		||||
 | 
			
		||||
	chip = &fwd->chip;
 | 
			
		||||
 | 
			
		||||
	/*
 | 
			
		||||
	 * If any of the GPIO lines are sleeping, then the entire forwarder
 | 
			
		||||
	 * will be sleeping.
 | 
			
		||||
	 * If any of the chips support .set_config(), then the forwarder will
 | 
			
		||||
	 * support setting configs.
 | 
			
		||||
	 */
 | 
			
		||||
	for (i = 0; i < ngpios; i++) {
 | 
			
		||||
		struct gpio_chip *parent = gpiod_to_chip(descs[i]);
 | 
			
		||||
 | 
			
		||||
		dev_dbg(dev, "%u => gpio-%d\n", i, desc_to_gpio(descs[i]));
 | 
			
		||||
 | 
			
		||||
		if (gpiod_cansleep(descs[i]))
 | 
			
		||||
			chip->can_sleep = true;
 | 
			
		||||
		if (parent && parent->set_config)
 | 
			
		||||
			chip->set_config = gpio_fwd_set_config;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	chip->label = label;
 | 
			
		||||
	chip->parent = dev;
 | 
			
		||||
	chip->owner = THIS_MODULE;
 | 
			
		||||
	chip->get_direction = gpio_fwd_get_direction;
 | 
			
		||||
	chip->direction_input = gpio_fwd_direction_input;
 | 
			
		||||
	chip->direction_output = gpio_fwd_direction_output;
 | 
			
		||||
	chip->get = gpio_fwd_get;
 | 
			
		||||
	chip->get_multiple = gpio_fwd_get_multiple;
 | 
			
		||||
	chip->set = gpio_fwd_set;
 | 
			
		||||
	chip->set_multiple = gpio_fwd_set_multiple;
 | 
			
		||||
	chip->base = -1;
 | 
			
		||||
	chip->ngpio = ngpios;
 | 
			
		||||
	fwd->descs = descs;
 | 
			
		||||
 | 
			
		||||
	if (chip->can_sleep)
 | 
			
		||||
		mutex_init(&fwd->mlock);
 | 
			
		||||
	else
 | 
			
		||||
		spin_lock_init(&fwd->slock);
 | 
			
		||||
 | 
			
		||||
	error = devm_gpiochip_add_data(dev, chip, fwd);
 | 
			
		||||
	if (error)
 | 
			
		||||
		return ERR_PTR(error);
 | 
			
		||||
 | 
			
		||||
	return fwd;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
/*
 | 
			
		||||
 *  GPIO Aggregator platform device
 | 
			
		||||
 */
 | 
			
		||||
 | 
			
		||||
static int gpio_aggregator_probe(struct platform_device *pdev)
 | 
			
		||||
{
 | 
			
		||||
	struct device *dev = &pdev->dev;
 | 
			
		||||
	struct gpio_desc **descs;
 | 
			
		||||
	struct gpiochip_fwd *fwd;
 | 
			
		||||
	int i, n;
 | 
			
		||||
 | 
			
		||||
	n = gpiod_count(dev, NULL);
 | 
			
		||||
	if (n < 0)
 | 
			
		||||
		return n;
 | 
			
		||||
 | 
			
		||||
	descs = devm_kmalloc_array(dev, n, sizeof(*descs), GFP_KERNEL);
 | 
			
		||||
	if (!descs)
 | 
			
		||||
		return -ENOMEM;
 | 
			
		||||
 | 
			
		||||
	for (i = 0; i < n; i++) {
 | 
			
		||||
		descs[i] = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
 | 
			
		||||
		if (IS_ERR(descs[i]))
 | 
			
		||||
			return PTR_ERR(descs[i]);
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	fwd = gpiochip_fwd_create(dev, n, descs);
 | 
			
		||||
	if (IS_ERR(fwd))
 | 
			
		||||
		return PTR_ERR(fwd);
 | 
			
		||||
 | 
			
		||||
	platform_set_drvdata(pdev, fwd);
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
#ifdef CONFIG_OF
 | 
			
		||||
static const struct of_device_id gpio_aggregator_dt_ids[] = {
 | 
			
		||||
	/*
 | 
			
		||||
	 * Add GPIO-operated devices controlled from userspace below,
 | 
			
		||||
	 * or use "driver_override" in sysfs
 | 
			
		||||
	 */
 | 
			
		||||
	{},
 | 
			
		||||
};
 | 
			
		||||
MODULE_DEVICE_TABLE(of, gpio_aggregator_dt_ids);
 | 
			
		||||
#endif
 | 
			
		||||
 | 
			
		||||
static struct platform_driver gpio_aggregator_driver = {
 | 
			
		||||
	.probe = gpio_aggregator_probe,
 | 
			
		||||
	.driver = {
 | 
			
		||||
		.name = DRV_NAME,
 | 
			
		||||
		.groups = gpio_aggregator_groups,
 | 
			
		||||
		.of_match_table = of_match_ptr(gpio_aggregator_dt_ids),
 | 
			
		||||
	},
 | 
			
		||||
};
 | 
			
		||||
 | 
			
		||||
static int __init gpio_aggregator_init(void)
 | 
			
		||||
{
 | 
			
		||||
	return platform_driver_register(&gpio_aggregator_driver);
 | 
			
		||||
}
 | 
			
		||||
module_init(gpio_aggregator_init);
 | 
			
		||||
 | 
			
		||||
static void __exit gpio_aggregator_exit(void)
 | 
			
		||||
{
 | 
			
		||||
	gpio_aggregator_remove_all();
 | 
			
		||||
	platform_driver_unregister(&gpio_aggregator_driver);
 | 
			
		||||
}
 | 
			
		||||
module_exit(gpio_aggregator_exit);
 | 
			
		||||
 | 
			
		||||
MODULE_AUTHOR("Geert Uytterhoeven <geert+renesas@glider.be>");
 | 
			
		||||
MODULE_DESCRIPTION("GPIO Aggregator");
 | 
			
		||||
MODULE_LICENSE("GPL v2");
 | 
			
		||||
		Loading…
	
		Reference in a new issue