From patchwork Tue Jun 16 10:40:50 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Doug Anderson X-Patchwork-Id: 11607137 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 55BE21392 for ; Tue, 16 Jun 2020 10:41:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 3989720776 for ; Tue, 16 Jun 2020 10:41:40 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="fi9cinkk" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728496AbgFPKla (ORCPT ); Tue, 16 Jun 2020 06:41:30 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55320 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728469AbgFPKlW (ORCPT ); Tue, 16 Jun 2020 06:41:22 -0400 Received: from mail-pg1-x543.google.com (mail-pg1-x543.google.com [IPv6:2607:f8b0:4864:20::543]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BB009C08C5C3 for ; Tue, 16 Jun 2020 03:41:22 -0700 (PDT) Received: by mail-pg1-x543.google.com with SMTP id u128so2146208pgu.13 for ; Tue, 16 Jun 2020 03:41:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=wPzcsZu19gLGHlfTpg/OVz60qYIP10yYC7Od6iya2fQ=; b=fi9cinkktR+lFKaArv2L5i3SkW2V2zi8UtNp33Wy74Aua59Fm+PF5Yqfb+WQ4Hcr1w JJrhwpirE5At/gcnA3IzafQ3pmIaLZayOLOVeKcOCU3MAbgJ8G/358NcBH6HG/WT8QiE xv7a6CcWTp0oBUx8bNfOw1IMeIFKYI7M8IJ10= 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:mime-version:content-transfer-encoding; bh=wPzcsZu19gLGHlfTpg/OVz60qYIP10yYC7Od6iya2fQ=; b=eqrdr87qsJk7wBiHOJ2IXyY028MYLKmVGgW9x9CC2PXO35B7RXTwfTJnZOVL3LRKGe LSKa4AIiHXVuvwPyWeLWfCogikghhe1QmnoXixdYEz917ZzsKwW5XpP7338QIYZSHNIB nRoavqc2EMmSF1CuPkS/3ajBUsNzYqYQvorcAtf3YtEHtsz7BES8nh/FTtEOI4NCLNlv xvUlqbhPdBKTeMRxZmVB3266ZiFls7Upp+yjvY1c0TgfkBLKSrWfx5QxySKkAXCnXyjW gkb1R2WPvq3vQN43U0RpYTe1EYIxuva/pAJrWW7KWMtOQomauRre9ff6oJOoL9X2CGVJ whMA== X-Gm-Message-State: AOAM532rhYWY9RVtPTkV2/tVLR0ZMebjM1XMI39aaX7gmpua4cHsNere Ff8z6HIjybX1UC8p+GnXx7tM/w== X-Google-Smtp-Source: ABdhPJwNARi0Kqm3Jnvas3QIe0jp32CNeyZFGnkYa+K2v8cg9KXzvug6VY8RJKi2tgtrvOeQU4mf7A== X-Received: by 2002:a63:e04a:: with SMTP id n10mr1552555pgj.157.1592304082218; Tue, 16 Jun 2020 03:41:22 -0700 (PDT) Received: from tictac2.mtv.corp.google.com ([2620:15c:202:1:24fa:e766:52c9:e3b2]) by smtp.gmail.com with ESMTPSA id 140sm16947400pfz.154.2020.06.16.03.41.21 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Jun 2020 03:41:21 -0700 (PDT) From: Douglas Anderson To: Mark Brown Cc: Alok Chauhan , skakit@codeaurora.org, swboyd@chromium.org, Douglas Anderson , Andy Gross , Bjorn Andersson , linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-spi@vger.kernel.org Subject: [PATCH v3 5/5] spi: spi-geni-qcom: Don't keep a local state variable Date: Tue, 16 Jun 2020 03:40:50 -0700 Message-Id: <20200616034044.v3.5.Ib1e6855405fc9c99916ab7c7dee84d73a8bf3d68@changeid> X-Mailer: git-send-email 2.27.0.290.gba653c62da-goog In-Reply-To: <20200616104050.84764-1-dianders@chromium.org> References: <20200616104050.84764-1-dianders@chromium.org> MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org The variable "cur_mcmd" kept track of our current state (idle, xfer, cs, cancel). We don't really need it, so get rid of it. Instead: * Use separate condition variables for "chip select done", "cancel done", and "abort done". This is important so that if a "done" comes through (perhaps some previous interrupt finally came through) it can't confuse the cancel/abort function. * Use the "done" interrupt only for when a chip select or transfer is done and we can tell the difference by looking at whether "cur_xfer" is NULL. This is mostly a no-op change. However, it is possible it could fix an issue where a super delayed interrupt for a cancel command could have confused our waiting for an abort command. Signed-off-by: Douglas Anderson --- Changes in v3: - ("spi: spi-geni-qcom: Don't keep a local state variable") new in v3. Changes in v2: None drivers/spi/spi-geni-qcom.c | 55 ++++++++++++++++++------------------- 1 file changed, 27 insertions(+), 28 deletions(-) diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c index 63a62548b078..6feea88d63ac 100644 --- a/drivers/spi/spi-geni-qcom.c +++ b/drivers/spi/spi-geni-qcom.c @@ -63,13 +63,6 @@ #define TIMESTAMP_AFTER BIT(3) #define POST_CMD_DELAY BIT(4) -enum spi_m_cmd_opcode { - CMD_NONE, - CMD_XFER, - CMD_CS, - CMD_CANCEL, -}; - struct spi_geni_master { struct geni_se se; struct device *dev; @@ -81,10 +74,11 @@ struct spi_geni_master { unsigned int tx_rem_bytes; unsigned int rx_rem_bytes; const struct spi_transfer *cur_xfer; - struct completion xfer_done; + struct completion cs_done; + struct completion cancel_done; + struct completion abort_done; unsigned int oversampling; spinlock_t lock; - enum spi_m_cmd_opcode cur_mcmd; int irq; }; @@ -126,20 +120,23 @@ static void handle_fifo_timeout(struct spi_master *spi, struct geni_se *se = &mas->se; spin_lock_irq(&mas->lock); - reinit_completion(&mas->xfer_done); - mas->cur_mcmd = CMD_CANCEL; - geni_se_cancel_m_cmd(se); + reinit_completion(&mas->cancel_done); writel(0, se->base + SE_GENI_TX_WATERMARK_REG); + mas->cur_xfer = NULL; + mas->tx_rem_bytes = mas->rx_rem_bytes = 0; + geni_se_cancel_m_cmd(se); spin_unlock_irq(&mas->lock); - time_left = wait_for_completion_timeout(&mas->xfer_done, HZ); + + time_left = wait_for_completion_timeout(&mas->cancel_done, HZ); if (time_left) return; spin_lock_irq(&mas->lock); - reinit_completion(&mas->xfer_done); + reinit_completion(&mas->abort_done); geni_se_abort_m_cmd(se); spin_unlock_irq(&mas->lock); - time_left = wait_for_completion_timeout(&mas->xfer_done, HZ); + + time_left = wait_for_completion_timeout(&mas->abort_done, HZ); if (!time_left) dev_err(mas->dev, "Failed to cancel/abort m_cmd\n"); } @@ -156,15 +153,14 @@ static void spi_geni_set_cs(struct spi_device *slv, bool set_flag) set_flag = !set_flag; spin_lock_irq(&mas->lock); - reinit_completion(&mas->xfer_done); - mas->cur_mcmd = CMD_CS; + reinit_completion(&mas->cs_done); if (set_flag) geni_se_setup_m_cmd(se, SPI_CS_ASSERT, 0); else geni_se_setup_m_cmd(se, SPI_CS_DEASSERT, 0); spin_unlock_irq(&mas->lock); - time_left = wait_for_completion_timeout(&mas->xfer_done, HZ); + time_left = wait_for_completion_timeout(&mas->cs_done, HZ); if (!time_left) handle_fifo_timeout(spi, NULL); @@ -383,7 +379,6 @@ static void setup_fifo_xfer(struct spi_transfer *xfer, mas->rx_rem_bytes = xfer->len; } writel(spi_tx_cfg, se->base + SE_SPI_TRANS_CFG); - mas->cur_mcmd = CMD_XFER; /* * Lock around right before we start the transfer since our @@ -520,11 +515,13 @@ static irqreturn_t geni_spi_isr(int irq, void *data) geni_spi_handle_tx(mas); if (m_irq & M_CMD_DONE_EN) { - if (mas->cur_mcmd == CMD_XFER) + if (mas->cur_xfer) { spi_finalize_current_transfer(spi); - else if (mas->cur_mcmd == CMD_CS) - complete(&mas->xfer_done); - mas->cur_mcmd = CMD_NONE; + mas->cur_xfer = NULL; + } else { + complete(&mas->cs_done); + } + /* * If this happens, then a CMD_DONE came before all the Tx * buffer bytes were sent out. This is unusual, log this @@ -546,10 +543,10 @@ static irqreturn_t geni_spi_isr(int irq, void *data) mas->rx_rem_bytes, mas->cur_bits_per_word); } - if ((m_irq & M_CMD_CANCEL_EN) || (m_irq & M_CMD_ABORT_EN)) { - mas->cur_mcmd = CMD_NONE; - complete(&mas->xfer_done); - } + if (m_irq & M_CMD_CANCEL_EN) + complete(&mas->cancel_done); + if (m_irq & M_CMD_ABORT_EN) + complete(&mas->abort_done); /* * It's safe or a good idea to Ack all of our our interrupts at the @@ -617,7 +614,9 @@ static int spi_geni_probe(struct platform_device *pdev) spi->handle_err = handle_fifo_timeout; spi->set_cs = spi_geni_set_cs; - init_completion(&mas->xfer_done); + init_completion(&mas->cs_done); + init_completion(&mas->cancel_done); + init_completion(&mas->abort_done); spin_lock_init(&mas->lock); pm_runtime_enable(dev);