From patchwork Mon Sep 17 12:08:06 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lubomir Rintel X-Patchwork-Id: 10602621 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 4E5DA157B for ; Mon, 17 Sep 2018 12:08:37 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 37BB2299DB for ; Mon, 17 Sep 2018 12:08:37 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 2B70B299E6; Mon, 17 Sep 2018 12:08:37 +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=-7.9 required=2.0 tests=BAYES_00,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 97C9B299DB for ; Mon, 17 Sep 2018 12:08:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728410AbeIQRfi (ORCPT ); Mon, 17 Sep 2018 13:35:38 -0400 Received: from shell.v3.sk ([90.176.6.54]:47271 "EHLO shell.v3.sk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728241AbeIQRfi (ORCPT ); Mon, 17 Sep 2018 13:35:38 -0400 Received: from localhost (localhost [127.0.0.1]) by zimbra.v3.sk (Postfix) with ESMTP id BD15AAF017; Mon, 17 Sep 2018 14:08:32 +0200 (CEST) Received: from shell.v3.sk ([127.0.0.1]) by localhost (zimbra.v3.sk [127.0.0.1]) (amavisd-new, port 10032) with ESMTP id cgrl8aeX_IwI; Mon, 17 Sep 2018 14:08:23 +0200 (CEST) Received: from localhost (localhost [127.0.0.1]) by zimbra.v3.sk (Postfix) with ESMTP id B33BEAEEAE; Mon, 17 Sep 2018 14:08:22 +0200 (CEST) X-Virus-Scanned: amavisd-new at zimbra.v3.sk Received: from shell.v3.sk ([127.0.0.1]) by localhost (zimbra.v3.sk [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id IjLmZae6jdm8; Mon, 17 Sep 2018 14:08:20 +0200 (CEST) Received: from belphegor.brq.redhat.com (nat-pool-brq-t.redhat.com [213.175.37.10]) by zimbra.v3.sk (Postfix) with ESMTPSA id 4DADAAEEE1; Mon, 17 Sep 2018 14:08:20 +0200 (CEST) From: Lubomir Rintel To: Geert Uytterhoeven Cc: linux-spi@vger.kernel.org, Lubomir Rintel Subject: [PATCH RFC 3/5] WIP spi: pxa2xx: Add slave mode support Date: Mon, 17 Sep 2018 14:08:06 +0200 Message-Id: <20180917120808.20224-4-lkundrak@v3.sk> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20180917120808.20224-1-lkundrak@v3.sk> References: <20180917120808.20224-1-lkundrak@v3.sk> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Tested on an OLPC XO-1.75 machine, where the Embedded Controller happens to be a SPI master. TODO: fix //chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH); Signed-off-by: Lubomir Rintel --- drivers/spi/spi-pxa2xx.c | 83 ++++++++++++++++++++++++++++++---- include/linux/spi/pxa2xx_spi.h | 1 + 2 files changed, 76 insertions(+), 8 deletions(-) diff --git a/drivers/spi/spi-pxa2xx.c b/drivers/spi/spi-pxa2xx.c index 58554c765a87..9552f5335679 100644 --- a/drivers/spi/spi-pxa2xx.c +++ b/drivers/spi/spi-pxa2xx.c @@ -626,6 +626,11 @@ static irqreturn_t interrupt_transfer(struct driver_data *drv_data) return IRQ_HANDLED; } + if (irq_status & SSSR_TUR) { + int_error_stop(drv_data, "interrupt_transfer: fifo underrun"); + return IRQ_HANDLED; + } + if (irq_status & SSSR_TINT) { pxa2xx_spi_write(drv_data, SSSR, SSSR_TINT); if (drv_data->read(drv_data)) { @@ -1071,6 +1076,11 @@ static int pxa2xx_spi_transfer_one(struct spi_controller *master, pxa2xx_spi_write(drv_data, SSTO, chip->timeout); } + if (spi_controller_is_slave(master)) { + while (drv_data->write(drv_data)) + ; + } + /* * Release the data by enabling service requests and interrupts, * without changing any mode bits @@ -1080,6 +1090,27 @@ static int pxa2xx_spi_transfer_one(struct spi_controller *master, return 1; } +static int pxa2xx_spi_slave_abort(struct spi_master *master) +{ + struct driver_data *drv_data = spi_controller_get_devdata(master); + + /* Stop and reset SSP */ + write_SSSR_CS(drv_data, drv_data->clear_sr); + reset_sccr1(drv_data); + if (!pxa25x_ssp_comp(drv_data)) + pxa2xx_spi_write(drv_data, SSTO, 0); + pxa2xx_spi_flush(drv_data); + pxa2xx_spi_write(drv_data, SSCR0, + pxa2xx_spi_read(drv_data, SSCR0) & ~SSCR0_SSE); + + dev_dbg(&drv_data->pdev->dev, "transfer aborted\n"); + + drv_data->master->cur_msg->status = -EINTR; + spi_finalize_current_transfer(drv_data->master); + + return 0; +} + static void pxa2xx_spi_handle_err(struct spi_controller *master, struct spi_message *msg) { @@ -1207,9 +1238,14 @@ static int setup(struct spi_device *spi) rx_thres = config->rx_threshold; break; default: - tx_thres = TX_THRESH_DFLT; tx_hi_thres = 0; - rx_thres = RX_THRESH_DFLT; + if (spi_controller_is_slave(drv_data->master)) { + tx_thres = 1; + rx_thres = 2; + } else { + tx_thres = TX_THRESH_DFLT; + rx_thres = RX_THRESH_DFLT; + } break; } @@ -1253,6 +1289,12 @@ static int setup(struct spi_device *spi) if (chip_info->enable_loopback) chip->cr1 = SSCR1_LBM; } + if (spi_controller_is_slave(drv_data->master)) { + chip->cr1 |= SSCR1_SCFR; + chip->cr1 |= SSCR1_SCLKDIR; + chip->cr1 |= SSCR1_SFRMDIR; + chip->cr1 |= SSCR1_SPH; + } chip->lpss_rx_threshold = SSIRF_RxThresh(rx_thres); chip->lpss_tx_threshold = SSITF_TxLoThresh(tx_thres) @@ -1289,7 +1331,7 @@ static int setup(struct spi_device *spi) break; } - chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH); + //chip->cr1 &= ~(SSCR1_SPO | SSCR1_SPH); chip->cr1 |= (((spi->mode & SPI_CPHA) != 0) ? SSCR1_SPH : 0) | (((spi->mode & SPI_CPOL) != 0) ? SSCR1_SPO : 0); @@ -1492,6 +1534,13 @@ pxa2xx_spi_init_pdata(struct platform_device *pdev) } #endif +#if CONFIG_OF + if (of_id) { + pdata->is_slave = of_property_read_bool(pdev->dev.of_node, + "spi-slave"); + } +#endif + ssp->clk = devm_clk_get(&pdev->dev, NULL); ssp->irq = platform_get_irq(pdev, 0); ssp->type = type; @@ -1557,7 +1606,11 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) return -ENODEV; } - master = spi_alloc_master(dev, sizeof(struct driver_data)); + if (platform_info->is_slave) + master = spi_alloc_slave(dev, sizeof(struct driver_data)); + else + master = spi_alloc_master(dev, sizeof(struct driver_data)); + if (!master) { dev_err(&pdev->dev, "cannot alloc spi_master\n"); pxa_ssp_free(ssp); @@ -1579,6 +1632,7 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) master->setup = setup; master->set_cs = pxa2xx_spi_set_cs; master->transfer_one = pxa2xx_spi_transfer_one; + master->slave_abort = pxa2xx_spi_slave_abort; master->handle_err = pxa2xx_spi_handle_err; master->unprepare_transfer_hardware = pxa2xx_spi_unprepare_transfer; master->fw_translate_cs = pxa2xx_spi_fw_translate_cs; @@ -1608,7 +1662,8 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) drv_data->int_cr1 = SSCR1_TIE | SSCR1_RIE | SSCR1_TINTE; drv_data->dma_cr1 = DEFAULT_DMA_CR1; drv_data->clear_sr = SSSR_ROR | SSSR_TINT; - drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS | SSSR_ROR; + drv_data->mask_sr = SSSR_TINT | SSSR_RFS | SSSR_TFS + | SSSR_ROR | SSSR_TUR; } status = request_irq(ssp->irq, ssp_int, IRQF_SHARED, dev_name(dev), @@ -1656,10 +1711,22 @@ static int pxa2xx_spi_probe(struct platform_device *pdev) pxa2xx_spi_write(drv_data, SSCR0, tmp); break; default: - tmp = SSCR1_RxTresh(RX_THRESH_DFLT) | - SSCR1_TxTresh(TX_THRESH_DFLT); + + if (spi_controller_is_slave(master)) { + tmp = SSCR1_SCFR | + SSCR1_SCLKDIR | + SSCR1_SFRMDIR | + SSCR1_RxTresh(2) | + SSCR1_TxTresh(1) | + SSCR1_SPH; + } else { + tmp = SSCR1_RxTresh(RX_THRESH_DFLT) | + SSCR1_TxTresh(TX_THRESH_DFLT); + } pxa2xx_spi_write(drv_data, SSCR1, tmp); - tmp = SSCR0_SCR(2) | SSCR0_Motorola | SSCR0_DataSize(8); + tmp = SSCR0_Motorola | SSCR0_DataSize(8); + if (!spi_controller_is_slave(master)) + tmp |= SSCR0_SCR(2); pxa2xx_spi_write(drv_data, SSCR0, tmp); break; } diff --git a/include/linux/spi/pxa2xx_spi.h b/include/linux/spi/pxa2xx_spi.h index 9ec4c147abbc..b0674e330ef6 100644 --- a/include/linux/spi/pxa2xx_spi.h +++ b/include/linux/spi/pxa2xx_spi.h @@ -25,6 +25,7 @@ struct dma_chan; struct pxa2xx_spi_master { u16 num_chipselect; u8 enable_dma; + bool is_slave; /* DMA engine specific config */ bool (*dma_filter)(struct dma_chan *chan, void *param);