Return-path: Received: from smtp.codeaurora.org ([198.145.29.96]:55452 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753418AbeBZOwj (ORCPT ); Mon, 26 Feb 2018 09:52:39 -0500 From: Kalle Valo To: Bas Vermeulen Cc: linux-wireless@vger.kernel.org, ath9k-devel@qca.qualcomm.com Subject: Re: [PATCH] ath9k: introduce endian_check module parameter References: <20180226090917.7iabysywbv6h4rqr@alienware17> <87y3jgt6sp.fsf@kamboji.qca.qualcomm.com> <7d6af051-2724-5dfc-cf69-376c0b501626@blackstar.nl> Date: Mon, 26 Feb 2018 16:52:33 +0200 In-Reply-To: <7d6af051-2724-5dfc-cf69-376c0b501626@blackstar.nl> (Bas Vermeulen's message of "Mon, 26 Feb 2018 11:07:27 +0100") Message-ID: <87a7vvu7ke.fsf@kamboji.qca.qualcomm.com> (sfid-20180226_155244_109249_28399A07) MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Bas Vermeulen writes: > On 26-02-18 10:54, Kalle Valo wrote: >> Bas Vermeulen writes: >> >>> A random (little endian eeprom'd) ar9278 card didn't work on my >>> PowerMac G5 without allowing the driver to byte-swap the eeprom. >>> >>> Introduce a module parameter endian_check to allow this to happen, >>> and the PCIe card to function correctly on BE powerpc. >>> >>> Signed-off-by: Bas Vermeulen >>> --- >>> drivers/net/wireless/ath/ath9k/init.c | 6 +++++- >>> 1 file changed, 5 insertions(+), 1 deletion(-) >>> >>> diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c >>> index fa58a32227f5..421039dc060a 100644 >>> --- a/drivers/net/wireless/ath/ath9k/init.c >>> +++ b/drivers/net/wireless/ath/ath9k/init.c >>> @@ -67,6 +67,9 @@ static int ath9k_ps_enable; >>> module_param_named(ps_enable, ath9k_ps_enable, int, 0444); >>> MODULE_PARM_DESC(ps_enable, "Enable WLAN PowerSave"); >>> +static int ath9k_endian_check; >>> +module_param_named(endian_check, ath9k_endian_check, int, 0444); >>> +MODULE_PARM_DESC(endian_check, "Check EEPROM for endianness compatibility"); >>> #ifdef CONFIG_ATH9K_CHANNEL_CONTEXT >>> int ath9k_use_chanctx; >>> @@ -587,7 +590,8 @@ static int ath9k_of_init(struct ath_softc *sc) >>> ether_addr_copy(common->macaddr, mac); >>> ah->ah_flags &= ~AH_USE_EEPROM; >>> - ah->ah_flags |= AH_NO_EEP_SWAP; >>> + if (!ath9k_endian_check) >>> + ah->ah_flags |= AH_NO_EEP_SWAP; >> A bit annoying to have a module parameter, isn't there any automatic way >> to detect/try this? But on the other hand I guess this isn't a common >> problem as nobody has reported this before? > > There is an automatic way to detect this, but that is disabled by the > AH_NO_EEP_SWAP flag. Ah, I didn't check the code at all. > The platform initialisation does not set this flag if the endian_check > member of pdata is set to true, but there is no way to not set this > when using a device tree. I used a module parameter instead of a > device tree variable because I don't know of a way to modify the > device tree my PowerMac boots with. Ok, makes sense. A module parameter is not an ideal solution I guess it's ok in this case. -- Kalle Valo