Revision dc280d93623927570da279e99393879dbbab39e7 authored by Thomas Gleixner on 21 December 2016, 19:19:49 UTC, committed by Thomas Gleixner on 25 December 2016, 09:47:42 UTC
Developers manage to overwrite states blindly without thought. That's fatal
and hard to debug. Add sanity checks to make it fail.

This requries to restructure the code so that the dynamic state allocation
happens in the same lock protected section as the actual store. Otherwise
the previous assignment of 'Reserved' to the name field would trigger the
overwrite check.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192111.675234535@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

1 parent 59fefd0
Raw File
pxa2xx_vpac270.c
/*
 * linux/drivers/pcmcia/pxa2xx_vpac270.c
 *
 * Driver for Voipac PXA270 PCMCIA and CF sockets
 *
 * Copyright (C) 2010-2011 Marek Vasut <marek.vasut@gmail.com>
 *
 * 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.
 *
 */

#include <linux/gpio.h>
#include <linux/module.h>
#include <linux/platform_device.h>

#include <asm/mach-types.h>

#include <mach/vpac270.h>

#include "soc_common.h"

static struct gpio vpac270_pcmcia_gpios[] = {
	{ GPIO107_VPAC270_PCMCIA_PPEN,	GPIOF_INIT_LOW,	"PCMCIA PPEN" },
	{ GPIO11_VPAC270_PCMCIA_RESET,	GPIOF_INIT_LOW,	"PCMCIA Reset" },
};

static struct gpio vpac270_cf_gpios[] = {
	{ GPIO16_VPAC270_CF_RESET,	GPIOF_INIT_LOW,	"CF Reset" },
};

static int vpac270_pcmcia_hw_init(struct soc_pcmcia_socket *skt)
{
	int ret;

	if (skt->nr == 0) {
		ret = gpio_request_array(vpac270_pcmcia_gpios,
				ARRAY_SIZE(vpac270_pcmcia_gpios));

		skt->stat[SOC_STAT_CD].gpio = GPIO84_VPAC270_PCMCIA_CD;
		skt->stat[SOC_STAT_CD].name = "PCMCIA CD";
		skt->stat[SOC_STAT_RDY].gpio = GPIO35_VPAC270_PCMCIA_RDY;
		skt->stat[SOC_STAT_RDY].name = "PCMCIA Ready";
	} else {
		ret = gpio_request_array(vpac270_cf_gpios,
				ARRAY_SIZE(vpac270_cf_gpios));

		skt->stat[SOC_STAT_CD].gpio = GPIO17_VPAC270_CF_CD;
		skt->stat[SOC_STAT_CD].name = "CF CD";
		skt->stat[SOC_STAT_RDY].gpio = GPIO12_VPAC270_CF_RDY;
		skt->stat[SOC_STAT_RDY].name = "CF Ready";
	}

	return ret;
}

static void vpac270_pcmcia_hw_shutdown(struct soc_pcmcia_socket *skt)
{
	if (skt->nr == 0)
		gpio_free_array(vpac270_pcmcia_gpios,
					ARRAY_SIZE(vpac270_pcmcia_gpios));
	else
		gpio_free_array(vpac270_cf_gpios,
					ARRAY_SIZE(vpac270_cf_gpios));
}

static void vpac270_pcmcia_socket_state(struct soc_pcmcia_socket *skt,
					struct pcmcia_state *state)
{
	state->vs_3v  = 1;
	state->vs_Xv  = 0;
}

static int
vpac270_pcmcia_configure_socket(struct soc_pcmcia_socket *skt,
				const socket_state_t *state)
{
	if (skt->nr == 0) {
		gpio_set_value(GPIO11_VPAC270_PCMCIA_RESET,
			(state->flags & SS_RESET));
		gpio_set_value(GPIO107_VPAC270_PCMCIA_PPEN,
			!(state->Vcc == 33 || state->Vcc == 50));
	} else {
		gpio_set_value(GPIO16_VPAC270_CF_RESET,
			(state->flags & SS_RESET));
	}

	return 0;
}

static struct pcmcia_low_level vpac270_pcmcia_ops = {
	.owner			= THIS_MODULE,

	.first			= 0,
	.nr			= 2,

	.hw_init		= vpac270_pcmcia_hw_init,
	.hw_shutdown		= vpac270_pcmcia_hw_shutdown,

	.socket_state		= vpac270_pcmcia_socket_state,
	.configure_socket	= vpac270_pcmcia_configure_socket,
};

static struct platform_device *vpac270_pcmcia_device;

static int __init vpac270_pcmcia_init(void)
{
	int ret;

	if (!machine_is_vpac270())
		return -ENODEV;

	vpac270_pcmcia_device = platform_device_alloc("pxa2xx-pcmcia", -1);
	if (!vpac270_pcmcia_device)
		return -ENOMEM;

	ret = platform_device_add_data(vpac270_pcmcia_device,
		&vpac270_pcmcia_ops, sizeof(vpac270_pcmcia_ops));

	if (!ret)
		ret = platform_device_add(vpac270_pcmcia_device);

	if (ret)
		platform_device_put(vpac270_pcmcia_device);

	return ret;
}

static void __exit vpac270_pcmcia_exit(void)
{
	platform_device_unregister(vpac270_pcmcia_device);
}

module_init(vpac270_pcmcia_init);
module_exit(vpac270_pcmcia_exit);

MODULE_AUTHOR("Marek Vasut <marek.vasut@gmail.com>");
MODULE_DESCRIPTION("PCMCIA support for Voipac PXA270");
MODULE_ALIAS("platform:pxa2xx-pcmcia");
MODULE_LICENSE("GPL");
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