From patchwork Mon Oct 15 06:38:29 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vignesh Raghavendra X-Patchwork-Id: 10641191 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 42CE2109C for ; Mon, 15 Oct 2018 06:40:40 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 323F229468 for ; Mon, 15 Oct 2018 06:40:40 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 304FB2949D; Mon, 15 Oct 2018 06:40:40 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-8.0 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 77C2A2958C for ; Mon, 15 Oct 2018 06:40:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726762AbeJOOY1 (ORCPT ); Mon, 15 Oct 2018 10:24:27 -0400 Received: from lelv0143.ext.ti.com ([198.47.23.248]:56796 "EHLO lelv0143.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726164AbeJOOY0 (ORCPT ); Mon, 15 Oct 2018 10:24:26 -0400 Received: from dflxv15.itg.ti.com ([128.247.5.124]) by lelv0143.ext.ti.com (8.15.2/8.15.2) with ESMTP id w9F6eUZ7005071; Mon, 15 Oct 2018 01:40:30 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ti.com; s=ti-com-17Q1; t=1539585630; bh=NMfktEsy6ADlWLO88Ej58ZRGV2fdwttsfjENaqW1DFg=; h=From:To:CC:Subject:Date:In-Reply-To:References; b=oP5Li7KmnqA9ugdaOgwaUPb6jNkNx1iEsADrMDgVTY4DmlgM7vx3fPDqOLlvnw+By 1Ll/CNHFHcOKPqVdW/QwDjzhZpjG53i7uUcGKXk0C5BYrDQ+KjofalEaGIC8gP0ch8 pVyiTcYIqHIl0aGb6985ninIUk1qS6J420RCZAaU= Received: from DLEE108.ent.ti.com (dlee108.ent.ti.com [157.170.170.38]) by dflxv15.itg.ti.com (8.14.3/8.13.8) with ESMTP id w9F6eUIC005972; Mon, 15 Oct 2018 01:40:30 -0500 Received: from DLEE108.ent.ti.com (157.170.170.38) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.1466.3; Mon, 15 Oct 2018 01:40:31 -0500 Received: from dlep32.itg.ti.com (157.170.170.100) by DLEE108.ent.ti.com (157.170.170.38) with Microsoft SMTP Server (version=TLS1_0, cipher=TLS_RSA_WITH_AES_256_CBC_SHA) id 15.1.1466.3 via Frontend Transport; Mon, 15 Oct 2018 01:40:31 -0500 Received: from a0132425.india.ti.com (ileax41-snat.itg.ti.com [10.172.224.153]) by dlep32.itg.ti.com (8.14.3/8.13.8) with ESMTP id w9F6eH4Q023129; Mon, 15 Oct 2018 01:40:28 -0500 From: Vignesh R To: Mark Brown CC: , , , Vignesh R , Sekhar Nori Subject: [PATCH 3/3] spi: omap2-mcspi: Add slave mode support Date: Mon, 15 Oct 2018 12:08:29 +0530 Message-ID: <20181015063829.26978-4-vigneshr@ti.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181015063829.26978-1-vigneshr@ti.com> References: <20181015063829.26978-1-vigneshr@ti.com> MIME-Version: 1.0 X-EXCLAIMER-MD-CONFIG: e1e8a2fd-e40a-4ac6-ac9b-f7e9cc9ee180 Sender: linux-omap-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Add support to use McSPI controller as SPI slave. In slave mode, DMA TX completion does not mean entire data has been shifted out as data might still be stuck in FIFO waiting for master to clock the bus. Therefore, add an IRQ handler for slave mode to know when entire data in FIFO has been shifted out. Signed-off-by: Vignesh R --- drivers/spi/spi-omap2-mcspi.c | 138 ++++++++++++++++++++++++++++++---- 1 file changed, 122 insertions(+), 16 deletions(-) diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 88469bb22235..f024c3fc3679 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -127,6 +127,7 @@ struct omap2_mcspi_regs { }; struct omap2_mcspi { + struct completion txdone; struct spi_master *master; /* Virtual base address of the controller */ void __iomem *base; @@ -136,6 +137,7 @@ struct omap2_mcspi { struct device *dev; struct omap2_mcspi_regs ctx; int fifo_depth; + bool slave_aborted; unsigned int pin_dir:1; }; @@ -275,19 +277,23 @@ static void omap2_mcspi_set_cs(struct spi_device *spi, bool enable) } } -static void omap2_mcspi_set_master_mode(struct spi_master *master) +static void omap2_mcspi_set_mode(struct spi_master *master) { struct omap2_mcspi *mcspi = spi_master_get_devdata(master); struct omap2_mcspi_regs *ctx = &mcspi->ctx; u32 l; /* - * Setup when switching from (reset default) slave mode - * to single-channel master mode + * Choose master or slave mode */ l = mcspi_read_reg(master, OMAP2_MCSPI_MODULCTRL); - l &= ~(OMAP2_MCSPI_MODULCTRL_STEST | OMAP2_MCSPI_MODULCTRL_MS); - l |= OMAP2_MCSPI_MODULCTRL_SINGLE; + l &= ~(OMAP2_MCSPI_MODULCTRL_STEST); + if (spi_controller_is_slave(master)) { + l |= (OMAP2_MCSPI_MODULCTRL_MS); + } else { + l &= ~(OMAP2_MCSPI_MODULCTRL_MS); + l |= OMAP2_MCSPI_MODULCTRL_SINGLE; + } mcspi_write_reg(master, OMAP2_MCSPI_MODULCTRL, l); ctx->modulctrl = l; @@ -356,6 +362,20 @@ static int mcspi_wait_for_reg_bit(void __iomem *reg, unsigned long bit) return readl_poll_timeout(reg, val, val & bit, 1, MSEC_PER_SEC); } +static int mcspi_wait_for_completion(struct omap2_mcspi *mcspi, + struct completion *x) +{ + if (spi_controller_is_slave(mcspi->master)) { + if (wait_for_completion_interruptible(x) || + mcspi->slave_aborted) + return -EINTR; + } else { + wait_for_completion(x); + } + + return 0; +} + static void omap2_mcspi_rx_callback(void *data) { struct spi_device *spi = data; @@ -505,7 +525,12 @@ omap2_mcspi_rx_dma(struct spi_device *spi, struct spi_transfer *xfer, dma_async_issue_pending(mcspi_dma->dma_rx); omap2_mcspi_set_dma_req(spi, 1, 1); - wait_for_completion(&mcspi_dma->dma_rx_completion); + ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_rx_completion); + if (ret || mcspi->slave_aborted) { + dmaengine_terminate_sync(mcspi_dma->dma_rx); + omap2_mcspi_set_dma_req(spi, 1, 0); + return 0; + } for (x = 0; x < nb_sizes; x++) kfree(sg_out[x]); @@ -604,14 +629,37 @@ omap2_mcspi_txrx_dma(struct spi_device *spi, struct spi_transfer *xfer) rx = xfer->rx_buf; tx = xfer->tx_buf; - if (tx != NULL) + mcspi->slave_aborted = false; + reinit_completion(&mcspi_dma->dma_tx_completion); + reinit_completion(&mcspi_dma->dma_rx_completion); + reinit_completion(&mcspi->txdone); + if (tx) { + /* Enable EOW IRQ to know end of tx in slave mode */ + if (spi_controller_is_slave(spi->master)) + mcspi_write_reg(spi->master, + OMAP2_MCSPI_IRQENABLE, + OMAP2_MCSPI_IRQSTATUS_EOW); omap2_mcspi_tx_dma(spi, xfer, cfg); + } if (rx != NULL) count = omap2_mcspi_rx_dma(spi, xfer, cfg, es); if (tx != NULL) { - wait_for_completion(&mcspi_dma->dma_tx_completion); + int ret; + + ret = mcspi_wait_for_completion(mcspi, &mcspi_dma->dma_tx_completion); + if (ret || mcspi->slave_aborted) { + dmaengine_terminate_sync(mcspi_dma->dma_tx); + omap2_mcspi_set_dma_req(spi, 0, 0); + return 0; + } + + if (spi_controller_is_slave(mcspi->master)) { + ret = mcspi_wait_for_completion(mcspi, &mcspi->txdone); + if (ret || mcspi->slave_aborted) + return 0; + } if (mcspi->fifo_depth > 0) { irqstat_reg = mcspi->base + OMAP2_MCSPI_IRQSTATUS; @@ -1068,6 +1116,36 @@ static void omap2_mcspi_cleanup(struct spi_device *spi) gpio_free(spi->cs_gpio); } +static irqreturn_t omap2_mcspi_irq_handler(int irq, void *data) +{ + struct omap2_mcspi *mcspi = data; + u32 irqstat; + + irqstat = mcspi_read_reg(mcspi->master, OMAP2_MCSPI_IRQSTATUS); + if (!irqstat) + return IRQ_NONE; + + /* Disable IRQ and wakeup slave xfer task */ + mcspi_write_reg(mcspi->master, OMAP2_MCSPI_IRQENABLE, 0); + if (irqstat & OMAP2_MCSPI_IRQSTATUS_EOW) + complete(&mcspi->txdone); + + return IRQ_HANDLED; +} + +static int omap2_mcspi_slave_abort(struct spi_master *master) +{ + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + struct omap2_mcspi_dma *mcspi_dma = mcspi->dma_channels; + + mcspi->slave_aborted = true; + complete(&mcspi_dma->dma_rx_completion); + complete(&mcspi_dma->dma_tx_completion); + complete(&mcspi->txdone); + + return 0; +} + static int omap2_mcspi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *t) @@ -1234,10 +1312,20 @@ static bool omap2_mcspi_can_dma(struct spi_master *master, struct spi_device *spi, struct spi_transfer *xfer) { + struct omap2_mcspi *mcspi = spi_master_get_devdata(spi->master); + struct omap2_mcspi_dma *mcspi_dma = + &mcspi->dma_channels[spi->chip_select]; + + if (!mcspi_dma->dma_rx || !mcspi_dma->dma_tx) + return false; + + if (spi_controller_is_slave(master)) + return true; + return (xfer->len >= DMA_MIN_BYTES); } -static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi) +static int omap2_mcspi_controller_setup(struct omap2_mcspi *mcspi) { struct spi_master *master = mcspi->master; struct omap2_mcspi_regs *ctx = &mcspi->ctx; @@ -1254,7 +1342,7 @@ static int omap2_mcspi_master_setup(struct omap2_mcspi *mcspi) OMAP2_MCSPI_WAKEUPENABLE_WKEN); ctx->wakeupenable = OMAP2_MCSPI_WAKEUPENABLE_WKEN; - omap2_mcspi_set_master_mode(master); + omap2_mcspi_set_mode(master); pm_runtime_mark_last_busy(mcspi->dev); pm_runtime_put_autosuspend(mcspi->dev); return 0; @@ -1329,11 +1417,12 @@ static int omap2_mcspi_probe(struct platform_device *pdev) struct device_node *node = pdev->dev.of_node; const struct of_device_id *match; - master = spi_alloc_master(&pdev->dev, sizeof *mcspi); - if (master == NULL) { - dev_dbg(&pdev->dev, "master allocation failed\n"); + if (of_property_read_bool(node, "spi-slave")) + master = spi_alloc_slave(&pdev->dev, sizeof(*mcspi)); + else + master = spi_alloc_master(&pdev->dev, sizeof(*mcspi)); + if (!master) return -ENOMEM; - } /* the spi->mode bits understood by this driver: */ master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_CS_HIGH; @@ -1345,6 +1434,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev) master->transfer_one = omap2_mcspi_transfer_one; master->set_cs = omap2_mcspi_set_cs; master->cleanup = omap2_mcspi_cleanup; + master->slave_abort = omap2_mcspi_slave_abort; master->dev.of_node = node; master->max_speed_hz = OMAP2_MCSPI_MAX_FREQ; master->min_speed_hz = OMAP2_MCSPI_MAX_FREQ >> 15; @@ -1396,15 +1486,31 @@ static int omap2_mcspi_probe(struct platform_device *pdev) sprintf(mcspi->dma_channels[i].dma_tx_ch_name, "tx%d", i); } + status = platform_get_irq(pdev, 0); + if (status == -EPROBE_DEFER) + goto free_master; + if (status < 0) { + dev_err(&pdev->dev, "no irq resource found\n"); + goto free_master; + } + init_completion(&mcspi->txdone); + status = devm_request_irq(&pdev->dev, status, + omap2_mcspi_irq_handler, 0, pdev->name, + mcspi); + if (status) { + dev_err(&pdev->dev, "Cannot request IRQ"); + goto free_master; + } + pm_runtime_use_autosuspend(&pdev->dev); pm_runtime_set_autosuspend_delay(&pdev->dev, SPI_AUTOSUSPEND_TIMEOUT); pm_runtime_enable(&pdev->dev); - status = omap2_mcspi_master_setup(mcspi); + status = omap2_mcspi_controller_setup(mcspi); if (status < 0) goto disable_pm; - status = devm_spi_register_master(&pdev->dev, master); + status = devm_spi_register_controller(&pdev->dev, master); if (status < 0) goto disable_pm;