From patchwork Sat Feb 27 17:29:46 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Mosberger-Tang X-Patchwork-Id: 388382 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, UNPARSEABLE_RELAY, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 22556C433E0 for ; Sat, 27 Feb 2021 17:36:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DA58964E33 for ; Sat, 27 Feb 2021 17:36:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230295AbhB0Reh (ORCPT ); Sat, 27 Feb 2021 12:34:37 -0500 Received: from o1.ptr2625.egauge.net ([167.89.112.53]:23958 "EHLO o1.ptr2625.egauge.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230234AbhB0Raq (ORCPT ); Sat, 27 Feb 2021 12:30:46 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=egauge.net; h=from:subject:in-reply-to:references:mime-version:to:cc: content-transfer-encoding:content-type; s=sgd; bh=A0nyiQH89foVd5buQULuUX9sSu6emJdGHJKg04xVrkE=; b=cqtFi9Butba+3WHwkSSUYHiYmVtD56+FH2qNwL+f5WJo+RH4cjYYhvxTsznkAb8b/HUk xj/2d7ohugMaHjxdkygj2IXSiavQ9vXXPahPny8T3d58VoWX7OrXouB6rXHbPeBAxtCwtL PQF3FQ67NZLjGVSdrjZh1hvaJCvmQPPHQ= Received: by filterdrecv-p3iad2-fdf5ff85d-l7rdf with SMTP id filterdrecv-p3iad2-fdf5ff85d-l7rdf-19-603A8189-3C 2021-02-27 17:29:45.765782176 +0000 UTC m=+1536136.654393572 Received: from pearl.egauge.net (unknown) by geopod-ismtpd-canary-0 (SG) with ESMTP id o3a_khVITRaV7NCD_YVfgQ Sat, 27 Feb 2021 17:29:45.547 +0000 (UTC) Received: by pearl.egauge.net (Postfix, from userid 1000) id 038BE7002F9; Sat, 27 Feb 2021 10:29:45 -0700 (MST) From: David Mosberger-Tang Subject: [PATCH v2 3/4] wilc1000: Check for errors at end of DMA write Date: Sat, 27 Feb 2021 17:29:46 +0000 (UTC) Message-Id: <20210227172818.1711071-3-davidm@egauge.net> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210224055135.1509200-1-davidm@egauge.net> References: <20210224055135.1509200-1-davidm@egauge.net> MIME-Version: 1.0 X-SG-EID: +kMxBqj35EdRUKoy8diX1j4AXmPtd302oan+iXZuF8m2Nw4HRW2irNspffT/khET6RJF6+Prbl0h/EtF1rRLvEXgQBWs9xCipqoFbZKGURIzqdaK16w70HkQ4OHG6IpCzbO03ln1UrcfE6pmuEHQBAd6+TwGP36ZKeSAyb+N/BWtx0861JfbCexEnDc5tIp5Spk4tUhgtOHRVY5yAhXbQJRmOpy6tRZyEuKFRtDgH0Dvm+IbhGA+2Jf6ON5p0URp8VDdDXp/gu0aLOqog8ayBA== To: linux-wireless@vger.kernel.org Cc: Ajay Singh , Claudiu Beznea , davidm@egauge.net X-Entity-ID: Xg4JGAcGrJFIz2kDG9eoaQ== Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org After a DMA write to the WILC chip, check for and report any errors. This is based on code from the wilc driver in the linux-at91 repository. Signed-off-by: David Mosberger-Tang --- drivers/net/wireless/microchip/wilc1000/spi.c | 62 ++++++++++++++++++- 1 file changed, 61 insertions(+), 1 deletion(-) diff --git a/drivers/net/wireless/microchip/wilc1000/spi.c b/drivers/net/wireless/microchip/wilc1000/spi.c index fca34d1999ec..0be93eabad69 100644 --- a/drivers/net/wireless/microchip/wilc1000/spi.c +++ b/drivers/net/wireless/microchip/wilc1000/spi.c @@ -47,6 +47,17 @@ static const struct wilc_hif_func wilc_hif_spi; #define SPI_ENABLE_VMM_RETRY_LIMIT 2 +/* SPI response fields (section 11.1.2 in ATWILC1000 User Guide): */ +#define RSP_START_FIELD GENMASK(7, 4) +#define RSP_TYPE_FIELD GENMASK(3, 0) + +/* SPI response values for the response fields: */ +#define RSP_START_TAG 0xc +#define RSP_TYPE_FIRST_PACKET 0x1 +#define RSP_TYPE_INNER_PACKET 0x2 +#define RSP_TYPE_LAST_PACKET 0x3 +#define RSP_STATE_NO_ERROR 0x00 + #define PROTOCOL_REG_PKT_SZ_MASK GENMASK(6, 4) #define PROTOCOL_REG_CRC16_MASK GENMASK(3, 3) #define PROTOCOL_REG_CRC7_MASK GENMASK(2, 2) @@ -750,6 +761,52 @@ static int wilc_spi_write_reg(struct wilc *wilc, u32 addr, u32 data) return 0; } +static int spi_data_rsp(struct wilc *wilc, u8 cmd) +{ + struct spi_device *spi = to_spi_device(wilc->dev); + int result, i; + u8 rsp[4]; + + /* + * The response to data packets is two bytes long. For + * efficiency's sake, wilc_spi_write() wisely ignores the + * responses for all packets but the final one. The downside + * of that optimization is that when the final data packet is + * short, we may receive (part of) the response to the + * second-to-last packet before the one for the final packet. + * To handle this, we always read 4 bytes and then search for + * the last byte that contains the "Response Start" code (0xc + * in the top 4 bits). We then know that this byte is the + * first response byte of the final data packet. + */ + result = wilc_spi_rx(wilc, rsp, sizeof(rsp)); + if (result) { + dev_err(&spi->dev, "Failed bus error...\n"); + return result; + } + + for (i = sizeof(rsp) - 2; i >= 0; --i) + if (FIELD_GET(RSP_START_FIELD, rsp[i]) == RSP_START_TAG) + break; + + if (i < 0) { + dev_err(&spi->dev, + "Data packet response missing (%02x %02x %02x %02x)\n", + rsp[0], rsp[1], rsp[2], rsp[3]); + return -1; + } + + /* rsp[i] is the last response start byte */ + + if (FIELD_GET(RSP_TYPE_FIELD, rsp[i]) != RSP_TYPE_LAST_PACKET + || rsp[i + 1] != RSP_STATE_NO_ERROR) { + dev_err(&spi->dev, "Data response error (%02x %02x)\n", + rsp[i], rsp[i + 1]); + return -1; + } + return 0; +} + static int wilc_spi_write(struct wilc *wilc, u32 addr, u8 *buf, u32 size) { struct spi_device *spi = to_spi_device(wilc->dev); @@ -777,7 +834,10 @@ static int wilc_spi_write(struct wilc *wilc, u32 addr, u8 *buf, u32 size) return result; } - return 0; + /* + * Data response + */ + return spi_data_rsp(wilc, CMD_DMA_EXT_WRITE); } /********************************************