From mboxrd@z Thu Jan 1 00:00:00 1970 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=-13.8 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 6860DC433E6 for ; Wed, 13 Jan 2021 20:16:34 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id DF67D222BB for ; Wed, 13 Jan 2021 20:16:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org DF67D222BB Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=openbmc-bounces+openbmc=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 4DGJcc0fvtzDrpp for ; Thu, 14 Jan 2021 07:16:32 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; spf=none (no SPF record) smtp.mailfrom=nuvoton.com (client-ip=212.199.177.27; helo=herzl.nuvoton.co.il; envelope-from=tomer.maimon@nuvoton.com; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=fail (p=none dis=none) header.from=gmail.com Received: from herzl.nuvoton.co.il (212.199.177.27.static.012.net.il [212.199.177.27]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4DGJGW05ggzDrSr for ; Thu, 14 Jan 2021 07:00:50 +1100 (AEDT) Received: from taln60.nuvoton.co.il (ntil-fw [212.199.177.25]) by herzl.nuvoton.co.il (8.13.8/8.13.8) with ESMTP id 10DK0RQB007590; Wed, 13 Jan 2021 22:00:27 +0200 Received: by taln60.nuvoton.co.il (Postfix, from userid 10070) id 3807663A17; Wed, 13 Jan 2021 22:00:28 +0200 (IST) From: Tomer Maimon To: openbmc@lists.ozlabs.org Subject: [PATCH linux dev-5.8 v3 10/12] spi: npcm-pspi: Add full duplex support Date: Wed, 13 Jan 2021 22:00:08 +0200 Message-Id: <20210113200010.71845-11-tmaimon77@gmail.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20210113200010.71845-1-tmaimon77@gmail.com> References: <20210113200010.71845-1-tmaimon77@gmail.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: openbmc@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Development list for OpenBMC List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Jeffery , Tomer Maimon , benjaminfair@google.com Errors-To: openbmc-bounces+openbmc=archiver.kernel.org@lists.ozlabs.org Sender: "openbmc" Modify the IRQ handler in the NPCM PSPI driver to support SPI full duplex communication. Signed-off-by: Tomer Maimon --- drivers/spi/spi-npcm-pspi.c | 75 +++++++++++++++---------------------- 1 file changed, 30 insertions(+), 45 deletions(-) diff --git a/drivers/spi/spi-npcm-pspi.c b/drivers/spi/spi-npcm-pspi.c index 87cd0233c60b..92fae0b23eb1 100644 --- a/drivers/spi/spi-npcm-pspi.c +++ b/drivers/spi/spi-npcm-pspi.c @@ -197,22 +197,22 @@ static void npcm_pspi_setup_transfer(struct spi_device *spi, static void npcm_pspi_send(struct npcm_pspi *priv) { int wsize; - u16 val; + u16 val = 0; wsize = min(bytes_per_word(priv->bits_per_word), priv->tx_bytes); priv->tx_bytes -= wsize; - if (!priv->tx_buf) - return; - switch (wsize) { case 1: - val = *priv->tx_buf++; + if (priv->tx_buf) + val = *priv->tx_buf++; iowrite8(val, NPCM_PSPI_DATA + priv->base); break; case 2: - val = *priv->tx_buf++; - val = *priv->tx_buf++ | (val << 8); + if (priv->tx_buf) { + val = *priv->tx_buf++; + val = *priv->tx_buf++ | (val << 8); + } iowrite16(val, NPCM_PSPI_DATA + priv->base); break; default: @@ -224,22 +224,24 @@ static void npcm_pspi_send(struct npcm_pspi *priv) static void npcm_pspi_recv(struct npcm_pspi *priv) { int rsize; - u16 val; + u16 val_16; + u8 val_8; rsize = min(bytes_per_word(priv->bits_per_word), priv->rx_bytes); priv->rx_bytes -= rsize; - if (!priv->rx_buf) - return; - switch (rsize) { case 1: - *priv->rx_buf++ = ioread8(priv->base + NPCM_PSPI_DATA); + val_8 = ioread8(priv->base + NPCM_PSPI_DATA); + if (priv->rx_buf) + *priv->rx_buf++ = val_8; break; case 2: - val = ioread16(priv->base + NPCM_PSPI_DATA); - *priv->rx_buf++ = (val >> 8); - *priv->rx_buf++ = val & 0xff; + val_16 = ioread16(priv->base + NPCM_PSPI_DATA); + if (priv->rx_buf) { + *priv->rx_buf++ = (val_16 >> 8); + *priv->rx_buf++ = val_16 & 0xff; + } break; default: WARN_ON_ONCE(1); @@ -298,43 +300,26 @@ static irqreturn_t npcm_pspi_handler(int irq, void *dev_id) struct npcm_pspi *priv = dev_id; u8 stat; - stat = ioread8(priv->base + NPCM_PSPI_STAT); - if (!priv->tx_buf && !priv->rx_buf) return IRQ_NONE; - if (priv->tx_buf) { - if (stat & NPCM_PSPI_STAT_RBF) { - ioread8(NPCM_PSPI_DATA + priv->base); - if (priv->tx_bytes == 0) { - npcm_pspi_disable(priv); - complete(&priv->xfer_done); - return IRQ_HANDLED; - } - } - - if ((stat & NPCM_PSPI_STAT_BSY) == 0) - if (priv->tx_bytes) - npcm_pspi_send(priv); + if (priv->tx_bytes == 0 && priv->rx_bytes == 0) { + npcm_pspi_disable(priv); + complete(&priv->xfer_done); + return IRQ_HANDLED; } - if (priv->rx_buf) { - if (stat & NPCM_PSPI_STAT_RBF) { - if (!priv->rx_bytes) - return IRQ_NONE; - - npcm_pspi_recv(priv); + stat = ioread8(priv->base + NPCM_PSPI_STAT); - if (!priv->rx_bytes) { - npcm_pspi_disable(priv); - complete(&priv->xfer_done); - return IRQ_HANDLED; - } - } + /* + * first we do the read since if we do the write we previous read might + * be lost (indeed low chances) + */ + if ((stat & NPCM_PSPI_STAT_RBF) && priv->rx_bytes) + npcm_pspi_recv(priv); - if (((stat & NPCM_PSPI_STAT_BSY) == 0) && !priv->tx_buf) - iowrite8(0x0, NPCM_PSPI_DATA + priv->base); - } + if (((stat & NPCM_PSPI_STAT_BSY) == 0) && priv->tx_bytes) + npcm_pspi_send(priv); return IRQ_HANDLED; } -- 2.22.0