Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 360d9bb5 authored by Kalle Valo's avatar Kalle Valo
Browse files

Revert "ath9k: export HW random number generator" 

This reverts commit 6301566e. Oleksij Rempel
noticed that the randomness doesn't look to be good enough and Stephan Mueller
commented:

"I would say that the discussed RNG does not seem fit for hooking it up with the
hwrandom framework."

http://lkml.kernel.org/g/3945775.m5HblJPgiO@tauon.atsec.com



So let's the revert the patch until we are sure that we can trust this random
generator.

Signed-off-by: default avatarKalle Valo <kvalo@codeaurora.org>
parent 92ff7a69

drivers/net/wireless/ath/ath9k/Kconfig

+0 −7
Original line number Diff line number Diff line
@@ -176,10 +176,3 @@ config ATH9K_HTC_DEBUGFS 
	depends on ATH9K_HTC && DEBUG_FS

	---help---

	  Say Y, if you need access to ath9k_htc's statistics.
 


config ATH9K_HWRNG

	bool "Random number generator support"

	depends on ATH9K && (HW_RANDOM = y || HW_RANDOM = ATH9K)

	default y

	---help---

	  Provides a hardware random number generator to the kernel.

drivers/net/wireless/ath/ath9k/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -15,7 +15,6 @@ ath9k-$(CONFIG_ATH9K_DFS_DEBUGFS) += dfs_debug.o 
ath9k-$(CONFIG_ATH9K_DFS_CERTIFIED) += dfs.o

ath9k-$(CONFIG_ATH9K_TX99) += tx99.o

ath9k-$(CONFIG_ATH9K_WOW) += wow.o

ath9k-$(CONFIG_ATH9K_HWRNG) += rng.o



ath9k-$(CONFIG_ATH9K_DEBUGFS) += debug.o

drivers/net/wireless/ath/ath9k/ath9k.h

+0 −23
Original line number Diff line number Diff line
@@ -23,7 +23,6 @@ 
#include <linux/leds.h>

#include <linux/completion.h>

#include <linux/time.h>

#include <linux/hw_random.h>



#include "common.h"

#include "debug.h"
@@ -1042,12 +1041,6 @@ struct ath_softc { 
	u32 wow_intr_before_sleep;

	bool force_wow;

#endif



#ifdef CONFIG_ATH9K_HWRNG

	struct hwrng rng;

	bool rng_initialized;

	u32 rng_last;

#endif

};



/********/
@@ -1070,22 +1063,6 @@ static inline int ath9k_tx99_send(struct ath_softc *sc, 
}

#endif /* CONFIG_ATH9K_TX99 */



/***************************/

/* Random Number Generator */

/***************************/

#ifdef CONFIG_ATH9K_HWRNG

void ath9k_rng_register(struct ath_softc *sc);

void ath9k_rng_unregister(struct ath_softc *sc);

#else

static inline void ath9k_rng_register(struct ath_softc *sc)

{

}



static inline void ath9k_rng_unregister(struct ath_softc *sc)

{

}

#endif



static inline void ath_read_cachesize(struct ath_common *common, int *csz)

{

	common->bus_ops->read_cachesize(common, csz);

drivers/net/wireless/ath/ath9k/main.c

+0 −4
Original line number Diff line number Diff line
@@ -739,8 +739,6 @@ static int ath9k_start(struct ieee80211_hw *hw) 


	ath9k_ps_restore(sc);



	ath9k_rng_register(sc);



	return 0;

}
@@ -830,8 +828,6 @@ static void ath9k_stop(struct ieee80211_hw *hw) 


	ath9k_deinit_channel_context(sc);



	ath9k_rng_unregister(sc);



	mutex_lock(&sc->mutex);



	ath_cancel_work(sc);

drivers/net/wireless/ath/ath9k/rng.c

deleted100644 → 0
+0 −75
Original line number Diff line number Diff line 
/*

 * Copyright (c) 2015 Qualcomm Atheros, Inc.

 *

 * Permission to use, copy, modify, and/or distribute this software for any

 * purpose with or without fee is hereby granted, provided that the above

 * copyright notice and this permission notice appear in all copies.

 *

 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES

 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF

 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR

 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN

 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF

 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

 */



#include "ath9k.h"

#include "hw.h"

#include "ar9003_phy.h"



static int ath9k_rng_data_read(struct hwrng *rng, u32 *data)

{

	u32 v1, v2;

	struct ath_softc *sc = (struct ath_softc *)rng->priv;

	struct ath_hw *ah = sc->sc_ah;



	ath9k_ps_wakeup(sc);



	REG_RMW_FIELD(ah, AR_PHY_TEST, AR_PHY_TEST_BBB_OBS_SEL, 5);

	REG_CLR_BIT(ah, AR_PHY_TEST, AR_PHY_TEST_RX_OBS_SEL_BIT5);

	REG_RMW_FIELD(ah, AR_PHY_TEST_CTL_STATUS, AR_PHY_TEST_CTL_RX_OBS_SEL, 0);



	v1 = REG_READ(ah, AR_PHY_TST_ADC);

	v2 = REG_READ(ah, AR_PHY_TST_ADC);



	ath9k_ps_restore(sc);



	/* wait for data ready */

	if (v1 && v2 && sc->rng_last != v1 && v1 != v2) {

		*data = (v1 & 0xffff) | (v2 << 16);

		sc->rng_last = v2;



		return sizeof(u32);

	}



	sc->rng_last = v2;



	return 0;

}



void ath9k_rng_register(struct ath_softc *sc)

{

	struct ath_hw *ah = sc->sc_ah;



	if (WARN_ON(sc->rng_initialized))

		return;



	if (!AR_SREV_9300_20_OR_LATER(ah))

		return;



	sc->rng.name = "ath9k";

	sc->rng.data_read = ath9k_rng_data_read;

	sc->rng.priv = (unsigned long)sc;



	if (!hwrng_register(&sc->rng))

		sc->rng_initialized = true;

}



void ath9k_rng_unregister(struct ath_softc *sc)

{

	if (sc->rng_initialized) {

		hwrng_unregister(&sc->rng);

		sc->rng_initialized = false;

	}

}