From patchwork Sat May 9 06:58:23 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dillon Min X-Patchwork-Id: 214661 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=-9.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable 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 16C72C54E49 for ; Sat, 9 May 2020 06:58:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E6C81217BA for ; Sat, 9 May 2020 06:58:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FTLFO1Bh" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729021AbgEIG6l (ORCPT ); Sat, 9 May 2020 02:58:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60888 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728471AbgEIG6j (ORCPT ); Sat, 9 May 2020 02:58:39 -0400 Received: from mail-pf1-x441.google.com (mail-pf1-x441.google.com [IPv6:2607:f8b0:4864:20::441]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1BA7DC061A0C; Fri, 8 May 2020 23:58:40 -0700 (PDT) Received: by mail-pf1-x441.google.com with SMTP id w65so2144589pfc.12; Fri, 08 May 2020 23:58:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=YXySs4zUZLsOuTSP8VAFnCNIxqD4YlvKNUR69g+WATI=; b=FTLFO1BhyZGIyN9NAcgxU6PdaFrch0mUM/kADDevRFco0mRjcUMeGp3fRcXLjnFs2M HkUDyWaeV+UqEiUYc4sC0h8l8Pj4LAacD7KR10AEg1F3VjMk+Zk5rXEaAO2ovkxFjho8 2J1bTAkJ/dJUp8FMG+dQ881N/ZSE6pnTqcOkF63Zck8AnebDsyYkD33Gb827KEEuio84 mulmTnyab9MXXOnwgUdWE5csUWJaOOdG4T25B5KEwAEzOBY+pdHkP7NAluiLPyPl0MbN cTdbkgGvdxJQhEIZAMGT+qcsPo68FYvLEDBM5EHdUT6wBfrIUFmuCzOMZvvqzdhx+eRV uuJQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=YXySs4zUZLsOuTSP8VAFnCNIxqD4YlvKNUR69g+WATI=; b=J/0txmshSymvYdLbnWTqJkPtNRNVFsECa2NCEFB0UgX2JMiJOhTL/6h4fJ4iiSalX3 yaCrxctlX5hNAfW3BEYKcXJEZ939xUAw6EAgJkFtDyw9crS+rsYbj2OZbnI12rn1/Qug Q92HXEfiVLXfsxOH6tY08AglCu9ehpCq12q4qPX+GaFWf5SbuP5BbP/BcppN1baE6llq sU39iABf5D0sTaAhevLf7FvpkjBS6zWQiUKzRxniKGnz5MoLtG9tv2IdibfkEDMHzStx hor4mhRashVg4UIkbWpxX89YyvJQGLxrhkeVQ5xGNVPHv2o/Mc3LopoMRJxv9V6vUM6g LZLQ== X-Gm-Message-State: AGi0PuaYardxdoz3zbWu+3zObMhKCvMN7xudTpBOrZqvFnamPU/ePXcc /lUzDxfdqbsxwiM4xVj1B7Y= X-Google-Smtp-Source: APiQypKJa/F9hGL23m/DdbkZTyV3jDAPDegtFd78ZZNfFPkERLH3hgikEbPDgMsm2gn6tNiCTtuDAQ== X-Received: by 2002:a63:41c2:: with SMTP id o185mr5363006pga.139.1589007519639; Fri, 08 May 2020 23:58:39 -0700 (PDT) Received: from fmin-OptiPlex-7060.nreal.work ([103.206.190.146]) by smtp.gmail.com with ESMTPSA id w192sm3811572pff.126.2020.05.08.23.58.36 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 08 May 2020 23:58:39 -0700 (PDT) From: dillon.minfei@gmail.com To: robh+dt@kernel.org, mcoquelin.stm32@gmail.com, alexandre.torgue@st.com, broonie@kernel.org, p.zabel@pengutronix.de Cc: devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, dillonhua@gmail.com, dillon min Subject: [PATCH 3/3] spi: stm32: Add SPI_SIMPLEX_RX, SPI_3WIRE_RX support for stm32f4 Date: Sat, 9 May 2020 14:58:23 +0800 Message-Id: <1589007503-9523-4-git-send-email-dillon.minfei@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1589007503-9523-1-git-send-email-dillon.minfei@gmail.com> References: <1589007503-9523-1-git-send-email-dillon.minfei@gmail.com> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org From: dillon min in l3gd20 driver startup, there is a setup failed error return from stm32 spi driver " [ 2.687630] st-gyro-spi spi0.0: supply vdd not found, using dummy regulator [ 2.696869] st-gyro-spi spi0.0: supply vddio not found, using dummy regulator [ 2.706707] spi_stm32 40015000.spi: SPI transfer setup failed [ 2.713741] st-gyro-spi spi0.0: SPI transfer failed: -22 [ 2.721096] spi_master spi0: failed to transfer one message from queue [ 2.729268] iio iio:device0: failed to read Who-Am-I register. [ 2.737504] st-gyro-spi: probe of spi0.0 failed with error -22 " after debug into spi-stm32 driver, st-gyro-spi split two steps to read l3gd20 id first: send command to l3gd20 with read id command in tx_buf, rx_buf is null. second: read id with tx_buf is null, rx_buf not null. so, for second step, stm32 driver recongise this process is SPI_SIMPLE_RX from stm32_spi_communication_type, but there is no related process for this type in stm32f4_spi_set_mode, then we get error from stm32_spi_transfer_one_setup. we can use two method to fix this bug. 1, use stm32 spi's "In unidirectional receive-only mode (BIDIMODE=0 and RXONLY=1)". but as our code running in sdram, the read latency is too large to get so many receive overrun error in interrupts handler. 2, use stm32 spi's "In full-duplex (BIDIMODE=0 and RXONLY=0)", as tx_buf is null, we must add dummy data sent out before read data. so, add stm32f4_spi_tx_dummy to handle this situation. Signed-off-by: dillon min --- drivers/spi/spi-stm32.c | 29 +++++++++++++++++++++++++---- 1 file changed, 25 insertions(+), 4 deletions(-) diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 44ac6eb3..bcf1ba7 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -388,6 +388,13 @@ static int stm32h7_spi_get_fifo_size(struct stm32_spi *spi) return count; } +static void stm32f4_spi_tx_dummy(struct stm32_spi *spi) +{ + if (spi->cur_bpw == 16) + writew_relaxed(0x5555, spi->base + STM32F4_SPI_DR); + else + writeb_relaxed(0x55, spi->base + STM32F4_SPI_DR); +} /** * stm32f4_spi_get_bpw_mask - Return bits per word mask * @spi: pointer to the spi controller data structure @@ -811,7 +818,9 @@ static irqreturn_t stm32f4_spi_irq_event(int irq, void *dev_id) mask |= STM32F4_SPI_SR_TXE; } - if (!spi->cur_usedma && spi->cur_comm == SPI_FULL_DUPLEX) { + if (!spi->cur_usedma && (spi->cur_comm == SPI_FULL_DUPLEX || + spi->cur_comm == SPI_SIMPLEX_RX || + spi->cur_comm == SPI_3WIRE_RX)) { /* TXE flag is set and is handled when RXNE flag occurs */ sr &= ~STM32F4_SPI_SR_TXE; mask |= STM32F4_SPI_SR_RXNE | STM32F4_SPI_SR_OVR; @@ -850,8 +859,10 @@ static irqreturn_t stm32f4_spi_irq_event(int irq, void *dev_id) stm32f4_spi_read_rx(spi); if (spi->rx_len == 0) end = true; - else /* Load data for discontinuous mode */ + else if (spi->tx_buf)/* Load data for discontinuous mode */ stm32f4_spi_write_tx(spi); + else if (spi->cur_comm == SPI_SIMPLEX_RX) + stm32f4_spi_tx_dummy(spi); } end_irq: @@ -1151,7 +1162,9 @@ static int stm32f4_spi_transfer_one_irq(struct stm32_spi *spi) /* Enable the interrupts relative to the current communication mode */ if (spi->cur_comm == SPI_SIMPLEX_TX || spi->cur_comm == SPI_3WIRE_TX) { cr2 |= STM32F4_SPI_CR2_TXEIE; - } else if (spi->cur_comm == SPI_FULL_DUPLEX) { + } else if (spi->cur_comm == SPI_FULL_DUPLEX || + spi->cur_comm == SPI_SIMPLEX_RX || + spi->cur_comm == SPI_3WIRE_RX) { /* In transmit-only mode, the OVR flag is set in the SR register * since the received data are never read. Therefore set OVR * interrupt only when rx buffer is available. @@ -1170,6 +1183,8 @@ static int stm32f4_spi_transfer_one_irq(struct stm32_spi *spi) /* starting data transfer when buffer is loaded */ if (spi->tx_buf) stm32f4_spi_write_tx(spi); + else if (spi->cur_comm == SPI_SIMPLEX_RX) + stm32f4_spi_tx_dummy(spi); spin_unlock_irqrestore(&spi->lock, flags); @@ -1462,10 +1477,16 @@ static int stm32f4_spi_set_mode(struct stm32_spi *spi, unsigned int comm_type) stm32_spi_set_bits(spi, STM32F4_SPI_CR1, STM32F4_SPI_CR1_BIDIMODE | STM32F4_SPI_CR1_BIDIOE); - } else if (comm_type == SPI_FULL_DUPLEX) { + } else if (comm_type == SPI_FULL_DUPLEX || + comm_type == SPI_SIMPLEX_RX) { stm32_spi_clr_bits(spi, STM32F4_SPI_CR1, STM32F4_SPI_CR1_BIDIMODE | STM32F4_SPI_CR1_BIDIOE); + } else if (comm_type == SPI_3WIRE_RX) { + stm32_spi_set_bits(spi, STM32F4_SPI_CR1, + STM32F4_SPI_CR1_BIDIMODE); + stm32_spi_clr_bits(spi, STM32F4_SPI_CR1, + STM32F4_SPI_CR1_BIDIOE); } else { return -EINVAL; }