From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Osipenko Subject: Re: [PATCH v1] sdhci: tegra: Add workaround for Broadcom WiFi Date: Wed, 11 Dec 2019 18:46:34 +0300 Message-ID: <28045442-6a1c-1e0b-0dfe-c36fa9de149a@gmail.com> References: <20191210014011.21987-1-digetx@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org To: Ulf Hansson Cc: Thierry Reding , Jonathan Hunter , Adrian Hunter , "linux-mmc@vger.kernel.org" , linux-tegra , Linux Kernel Mailing List List-Id: linux-tegra@vger.kernel.org Hello Ulf, 11.12.2019 11:11, Ulf Hansson пишет: > On Tue, 10 Dec 2019 at 02:40, Dmitry Osipenko wrote: >> >> All Tegra20 boards that have embedded Broadcom WiFi SDIO chip are affected >> by a problem where WiFi chip reports CCCR v1.10, while it should v1.20. >> In a result high-speed mode isn't enabled for the WiFi card and this >> results in a malfunctioning SDIO communication. > > Does that also mean SDIO_SPEED_SHS bit is set when reading SDIO_CCCR_SPEED? Yes, the SDIO_SPEED_SHS bit is set. >> brcmfmac: brcmf_sdio_readframes: read 304 bytes from channel 1 failed: -84 >> brcmfmac: brcmf_sdio_rxfail: abort command, terminate frame, send NAK >> >> Downstream kernels are overriding card's CCCR info in SDHCI driver to fix >> the problem, let's do the same in upstream. >> >> The change is inspired by omap_hsmmc_init_card() of OMAP's HSMMC driver, >> which overrides card's info for the TI wl1251 WiFi. > > This is a temporary solution and should be replaced by doing the DT > parsing during > > So, yes, let's see if we can use a card quirk instead. That's the first option. > > A second option is simply to parse the DT subnode for a new DT > property during mmc_sdio_init_card(). Along the lines of what we do > for the broken-hpi DT binding for eMMC. Let's try the first option. My understanding is that the problem affects only the specific model of the WiFi chip and it's not a board-specific problem. I'll add Broadcom driver people to CC for the next version of the patch, maybe they'll have something to say. [snip]