From patchwork Wed Jun 14 10:26:27 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Valentin Caron X-Patchwork-Id: 692964 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 31610C04A6A for ; Wed, 14 Jun 2023 10:30:55 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243592AbjFNKay (ORCPT ); Wed, 14 Jun 2023 06:30:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40442 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S244340AbjFNKaL (ORCPT ); Wed, 14 Jun 2023 06:30:11 -0400 Received: from mx07-00178001.pphosted.com (mx08-00178001.pphosted.com [91.207.212.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2D44A26B5; Wed, 14 Jun 2023 03:28:52 -0700 (PDT) Received: from pps.filterd (m0046660.ppops.net [127.0.0.1]) by mx07-00178001.pphosted.com (8.17.1.19/8.17.1.19) with ESMTP id 35E7mpw6028680; Wed, 14 Jun 2023 12:27:50 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=foss.st.com; h=from : to : cc : subject : date : message-id : in-reply-to : references : mime-version : content-transfer-encoding : content-type; s=selector1; bh=NOFrlQ5Me3hzStdXEAgB1aazavyz618BJAIRDuOKyNE=; b=0bR/IGmgPJgeQONbC/L42DXmHd/fwAWdu7ogJvPdDmy2KURS9vvWvec3zGBR6wch3/Li aTSnpw3CsqH/hScD9xTzTZNDUadM2CBCTb2Cyd52pjDsN1LF0HQzPakXJCCnPL7jqGHO ZMOi7U2uxJ94TwY7ViNRSTF6qzsEH8V7IlTM6MU4whZ9Z+rpU+bepdMXojhsOBQ/IIhB jWC6sB9nSVFoaIdb/pvkbNyh5LnaumPPCGfmZyZpJWwZHay0yVztgQ7C3R2bAXctY/3A CqvEo6p4Lu3b93onJG2BBdWdYRQjOSdAieOEEXx0QJrvwktH3tZ5LxZXbNCpCUW6I7F1 ig== Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com (PPS) with ESMTPS id 3r79g59760-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Wed, 14 Jun 2023 12:27:50 +0200 Received: from euls16034.sgp.st.com (euls16034.sgp.st.com [10.75.44.20]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id 3839B10002A; Wed, 14 Jun 2023 12:27:50 +0200 (CEST) Received: from Webmail-eu.st.com (shfdag1node1.st.com [10.75.129.69]) by euls16034.sgp.st.com (STMicroelectronics) with ESMTP id 2F0192278AE; Wed, 14 Jun 2023 12:27:50 +0200 (CEST) Received: from localhost (10.252.29.239) by SHFDAG1NODE1.st.com (10.75.129.69) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.21; Wed, 14 Jun 2023 12:27:49 +0200 From: Valentin Caron To: Mark Brown , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Alexandre Torgue , Alain Volmat CC: , , , , , Valentin Caron Subject: [PATCH v2 4/4] spi: stm32: introduction of stm32h7 SPI slave support Date: Wed, 14 Jun 2023 12:26:27 +0200 Message-ID: <20230614102628.202936-5-valentin.caron@foss.st.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230614102628.202936-1-valentin.caron@foss.st.com> References: <20230614102628.202936-1-valentin.caron@foss.st.com> MIME-Version: 1.0 X-Originating-IP: [10.252.29.239] X-ClientProxiedBy: SHFCAS1NODE2.st.com (10.75.129.73) To SHFDAG1NODE1.st.com (10.75.129.69) X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.205,Aquarius:18.0.957,Hydra:6.0.573,FMLib:17.11.176.26 definitions=2023-06-14_06,2023-06-14_01,2023-05-22_02 Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org Add support for stm32h7 to use SPI controller in slave role. In such case, the spi instance should have the spi-slave property defined. Signed-off-by: Alain Volmat Signed-off-by: Valentin Caron --- drivers/spi/Kconfig | 1 + drivers/spi/spi-stm32.c | 112 ++++++++++++++++++++++++++++------------ 2 files changed, 79 insertions(+), 34 deletions(-) diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 3de2ebe8294a..14810d24733b 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -936,6 +936,7 @@ config SPI_SPRD_ADI config SPI_STM32 tristate "STMicroelectronics STM32 SPI controller" depends on ARCH_STM32 || COMPILE_TEST + select SPI_SLAVE help SPI driver for STMicroelectronics STM32 SoCs. diff --git a/drivers/spi/spi-stm32.c b/drivers/spi/spi-stm32.c index 82fbd20e8a96..2db6f93654d7 100644 --- a/drivers/spi/spi-stm32.c +++ b/drivers/spi/spi-stm32.c @@ -117,6 +117,7 @@ #define STM32H7_SPI_CFG2_CPHA BIT(24) #define STM32H7_SPI_CFG2_CPOL BIT(25) #define STM32H7_SPI_CFG2_SSM BIT(26) +#define STM32H7_SPI_CFG2_SSIOP BIT(28) #define STM32H7_SPI_CFG2_AFCNTR BIT(31) /* STM32H7_SPI_IER bit fields */ @@ -170,6 +171,10 @@ */ #define SPI_DMA_MIN_BYTES 16 +/* STM32 SPI driver helpers */ +#define STM32_SPI_MASTER_MODE(stm32_spi) (!(stm32_spi)->slave_mode) +#define STM32_SPI_SLAVE_MODE(stm32_spi) ((stm32_spi)->slave_mode) + /** * struct stm32_spi_reg - stm32 SPI register & bitfield desc * @reg: register offset @@ -190,6 +195,7 @@ struct stm32_spi_reg { * @cpol: clock polarity register and polarity bit * @cpha: clock phase register and phase bit * @lsb_first: LSB transmitted first register and bit + * @cs_high: chips select active value * @br: baud rate register and bitfields * @rx: SPI RX data register * @tx: SPI TX data register @@ -201,6 +207,7 @@ struct stm32_spi_regspec { const struct stm32_spi_reg cpol; const struct stm32_spi_reg cpha; const struct stm32_spi_reg lsb_first; + const struct stm32_spi_reg cs_high; const struct stm32_spi_reg br; const struct stm32_spi_reg rx; const struct stm32_spi_reg tx; @@ -280,6 +287,7 @@ struct stm32_spi_cfg { * @dma_tx: dma channel for TX transfer * @dma_rx: dma channel for RX transfer * @phys_addr: SPI registers physical base address + * @slave_mode: the controller is configured as SPI slave */ struct stm32_spi { struct device *dev; @@ -307,6 +315,8 @@ struct stm32_spi { struct dma_chan *dma_tx; struct dma_chan *dma_rx; dma_addr_t phys_addr; + + bool slave_mode; }; static const struct stm32_spi_regspec stm32f4_spi_regspec = { @@ -318,6 +328,7 @@ static const struct stm32_spi_regspec stm32f4_spi_regspec = { .cpol = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_CPOL }, .cpha = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_CPHA }, .lsb_first = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_LSBFRST }, + .cs_high = {}, .br = { STM32F4_SPI_CR1, STM32F4_SPI_CR1_BR, STM32F4_SPI_CR1_BR_SHIFT }, .rx = { STM32F4_SPI_DR }, @@ -336,6 +347,7 @@ static const struct stm32_spi_regspec stm32h7_spi_regspec = { .cpol = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPOL }, .cpha = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_CPHA }, .lsb_first = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_LSBFRST }, + .cs_high = { STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_SSIOP }, .br = { STM32H7_SPI_CFG1, STM32H7_SPI_CFG1_MBR, STM32H7_SPI_CFG1_MBR_SHIFT }, @@ -971,6 +983,11 @@ static int stm32_spi_prepare_msg(struct spi_controller *ctrl, else clrb |= spi->cfg->regs->lsb_first.mask; + if (STM32_SPI_SLAVE_MODE(spi) && spi_dev->mode & SPI_CS_HIGH) + setb |= spi->cfg->regs->cs_high.mask; + else + clrb |= spi->cfg->regs->cs_high.mask; + dev_dbg(spi->dev, "cpol=%d cpha=%d lsb_first=%d cs_high=%d\n", !!(spi_dev->mode & SPI_CPOL), !!(spi_dev->mode & SPI_CPHA), @@ -1161,7 +1178,8 @@ static int stm32h7_spi_transfer_one_irq(struct stm32_spi *spi) if (spi->tx_buf) stm32h7_spi_write_txfifo(spi); - stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART); + if (STM32_SPI_MASTER_MODE(spi)) + stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART); writel_relaxed(ier, spi->base + STM32H7_SPI_IER); @@ -1208,7 +1226,8 @@ static void stm32h7_spi_transfer_one_dma_start(struct stm32_spi *spi) stm32_spi_enable(spi); - stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART); + if (STM32_SPI_MASTER_MODE(spi)) + stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_CSTART); } /** @@ -1536,16 +1555,18 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi, spi->cfg->set_bpw(spi); /* Update spi->cur_speed with real clock speed */ - mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz, - spi->cfg->baud_rate_div_min, - spi->cfg->baud_rate_div_max); - if (mbr < 0) { - ret = mbr; - goto out; - } + if (STM32_SPI_MASTER_MODE(spi)) { + mbr = stm32_spi_prepare_mbr(spi, transfer->speed_hz, + spi->cfg->baud_rate_div_min, + spi->cfg->baud_rate_div_max); + if (mbr < 0) { + ret = mbr; + goto out; + } - transfer->speed_hz = spi->cur_speed; - stm32_spi_set_mbr(spi, mbr); + transfer->speed_hz = spi->cur_speed; + stm32_spi_set_mbr(spi, mbr); + } comm_type = stm32_spi_communication_type(spi_dev, transfer); ret = spi->cfg->set_mode(spi, comm_type); @@ -1554,7 +1575,7 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi, spi->cur_comm = comm_type; - if (spi->cfg->set_data_idleness) + if (STM32_SPI_MASTER_MODE(spi) && spi->cfg->set_data_idleness) spi->cfg->set_data_idleness(spi, transfer->len); if (spi->cur_bpw <= 8) @@ -1575,7 +1596,8 @@ static int stm32_spi_transfer_one_setup(struct stm32_spi *spi, dev_dbg(spi->dev, "data frame of %d-bit, data packet of %d data frames\n", spi->cur_bpw, spi->cur_fthlv); - dev_dbg(spi->dev, "speed set to %dHz\n", spi->cur_speed); + if (STM32_SPI_MASTER_MODE(spi)) + dev_dbg(spi->dev, "speed set to %dHz\n", spi->cur_speed); dev_dbg(spi->dev, "transfer of %d bytes (%d data frames)\n", spi->cur_xferlen, nb_words); dev_dbg(spi->dev, "dma %s\n", @@ -1670,12 +1692,13 @@ static int stm32f4_spi_config(struct stm32_spi *spi) } /** - * stm32h7_spi_config - Configure SPI controller as SPI master + * stm32h7_spi_config - Configure SPI controller * @spi: pointer to the spi controller data structure */ static int stm32h7_spi_config(struct stm32_spi *spi) { unsigned long flags; + u32 cr1 = 0, cfg2 = 0; spin_lock_irqsave(&spi->lock, flags); @@ -1683,24 +1706,28 @@ static int stm32h7_spi_config(struct stm32_spi *spi) stm32_spi_clr_bits(spi, STM32H7_SPI_I2SCFGR, STM32H7_SPI_I2SCFGR_I2SMOD); - /* - * - SS input value high - * - transmitter half duplex direction - * - automatic communication suspend when RX-Fifo is full - */ - stm32_spi_set_bits(spi, STM32H7_SPI_CR1, STM32H7_SPI_CR1_SSI | - STM32H7_SPI_CR1_HDDIR | - STM32H7_SPI_CR1_MASRX); + if (STM32_SPI_SLAVE_MODE(spi)) { + /* Use native slave select */ + cfg2 &= ~STM32H7_SPI_CFG2_SSM; + } else { + /* + * - Transmitter half duplex direction + * - Automatic communication suspend when RX-Fifo is full + * - SS input value high + */ + cr1 |= STM32H7_SPI_CR1_HDDIR | STM32H7_SPI_CR1_MASRX | STM32H7_SPI_CR1_SSI; - /* - * - Set the master mode (default Motorola mode) - * - Consider 1 master/n slaves configuration and - * SS input value is determined by the SSI bit - * - keep control of all associated GPIOs - */ - stm32_spi_set_bits(spi, STM32H7_SPI_CFG2, STM32H7_SPI_CFG2_MASTER | - STM32H7_SPI_CFG2_SSM | - STM32H7_SPI_CFG2_AFCNTR); + /* + * - Set the master mode (default Motorola mode) + * - Consider 1 master/n slaves configuration and + * SS input value is determined by the SSI bit + * - keep control of all associated GPIOs + */ + cfg2 |= STM32H7_SPI_CFG2_MASTER | STM32H7_SPI_CFG2_SSM | STM32H7_SPI_CFG2_AFCNTR; + } + + stm32_spi_set_bits(spi, STM32H7_SPI_CR1, cr1); + stm32_spi_set_bits(spi, STM32H7_SPI_CFG2, cfg2); spin_unlock_irqrestore(&spi->lock, flags); @@ -1756,17 +1783,30 @@ static const struct of_device_id stm32_spi_of_match[] = { }; MODULE_DEVICE_TABLE(of, stm32_spi_of_match); +static int stm32h7_spi_slave_abort(struct spi_controller *ctrl) +{ + spi_finalize_current_transfer(ctrl); + return 0; +} + static int stm32_spi_probe(struct platform_device *pdev) { struct spi_controller *ctrl; struct stm32_spi *spi; struct resource *res; struct reset_control *rst; + struct device_node *np = pdev->dev.of_node; + bool slave_mode; int ret; - ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(struct stm32_spi)); + slave_mode = of_property_read_bool(np, "spi-slave"); + + if (slave_mode) + ctrl = devm_spi_alloc_slave(&pdev->dev, sizeof(struct stm32_spi)); + else + ctrl = devm_spi_alloc_master(&pdev->dev, sizeof(struct stm32_spi)); if (!ctrl) { - dev_err(&pdev->dev, "spi master allocation failed\n"); + dev_err(&pdev->dev, "spi controller allocation failed\n"); return -ENOMEM; } platform_set_drvdata(pdev, ctrl); @@ -1774,6 +1814,7 @@ static int stm32_spi_probe(struct platform_device *pdev) spi = spi_controller_get_devdata(ctrl); spi->dev = &pdev->dev; spi->ctrl = ctrl; + spi->slave_mode = slave_mode; spin_lock_init(&spi->lock); spi->cfg = (const struct stm32_spi_cfg *) @@ -1856,6 +1897,8 @@ static int stm32_spi_probe(struct platform_device *pdev) ctrl->transfer_one = stm32_spi_transfer_one; ctrl->unprepare_message = stm32_spi_unprepare_msg; ctrl->flags = spi->cfg->flags; + if (STM32_SPI_SLAVE_MODE(spi)) + ctrl->slave_abort = stm32h7_spi_slave_abort; spi->dma_tx = dma_request_chan(spi->dev, "tx"); if (IS_ERR(spi->dma_tx)) { @@ -1901,7 +1944,8 @@ static int stm32_spi_probe(struct platform_device *pdev) pm_runtime_mark_last_busy(&pdev->dev); pm_runtime_put_autosuspend(&pdev->dev); - dev_info(&pdev->dev, "driver initialized\n"); + dev_info(&pdev->dev, "driver initialized (%s mode)\n", + STM32_SPI_MASTER_MODE(spi) ? "master" : "slave"); return 0;