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Revert "ath9k: export HW random number generator"

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This reverts commit 6301566e0b. 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: Kalle Valo <kvalo@codeaurora.org>
This commit is contained in:
Kalle Valo 2015-07-31 10:17:35 +03:00
parent 92ff7a698b
commit 360d9bb5ee
5 changed files with 0 additions and 110 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/net/wireless/ath/ath9k/Kconfig
View File

@ -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.

1
drivers/net/wireless/ath/ath9k/Makefile
View File

@ -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

23
drivers/net/wireless/ath/ath9k/ath9k.h
View File

@ -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);

4
drivers/net/wireless/ath/ath9k/main.c
View File

@ -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);

75
drivers/net/wireless/ath/ath9k/rng.c
View File

@ -1,75 +0,0 @@
/*
* 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;
}
}