From patchwork Fri Jun 19 01:43:40 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xu Yilun X-Patchwork-Id: 11613097 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 836FA618 for ; Fri, 19 Jun 2020 01:48:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 757672088E for ; Fri, 19 Jun 2020 01:48:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730753AbgFSBsO (ORCPT ); Thu, 18 Jun 2020 21:48:14 -0400 Received: from mga06.intel.com ([134.134.136.31]:64021 "EHLO mga06.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727853AbgFSBsJ (ORCPT ); Thu, 18 Jun 2020 21:48:09 -0400 IronPort-SDR: DHnxHRxFDv/mZohp4AW1/E0u/tVr4VIQ7GAXLOeWr/qcPAL4kyb5Xc+VpeJN9gKNRSNsXdbRn4 KVrIkiGMux7Q== X-IronPort-AV: E=McAfee;i="6000,8403,9656"; a="204278283" X-IronPort-AV: E=Sophos;i="5.75,253,1589266800"; d="scan'208";a="204278283" X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jun 2020 18:48:08 -0700 IronPort-SDR: lcr/lrYanhgsrbvVRcd0eo0VGSY8sHHwAOkWRQpE+XmouSG5vPyrU+paT9zavhgEKGf2dxoPzS 8NryKGx8OLBA== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.75,253,1589266800"; d="scan'208";a="263746062" Received: from yilunxu-optiplex-7050.sh.intel.com ([10.239.159.141]) by fmsmga008.fm.intel.com with ESMTP; 18 Jun 2020 18:48:00 -0700 From: Xu Yilun To: broonie@kernel.org, linux-spi@vger.kernel.org, linux-kernel@vger.kernel.org Cc: trix@redhat.com, yilun.xu@intel.com, hao.wu@intel.com, matthew.gerlach@linux.intel.com, russell.h.weight@intel.com Subject: [RESEND PATCH v2 2/3] spi: altera: support indirect access to the registers Date: Fri, 19 Jun 2020 09:43:40 +0800 Message-Id: <1592531021-11412-3-git-send-email-yilun.xu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1592531021-11412-1-git-send-email-yilun.xu@intel.com> References: <1592531021-11412-1-git-send-email-yilun.xu@intel.com> Sender: linux-spi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-spi@vger.kernel.org This patch adds support for indirect access to the registers via parent regmap. The use case is, the spi master is a sub device of a Multifunction device, which is connected to host by some indirect bus. To support this device type, a new platform_device_id is introduced, and the driver tries to get parent regmap for register accessing like many MFD sub device drivers do. Signed-off-by: Xu Yilun Signed-off-by: Matthew Gerlach Signed-off-by: Wu Hao Signed-off-by: Russ Weight Reviewed-by : Tom Rix --- drivers/spi/spi-altera.c | 62 ++++++++++++++++++++++++++++++++++++------------ 1 file changed, 47 insertions(+), 15 deletions(-) diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c index b215bdf..4f7717f 100644 --- a/drivers/spi/spi-altera.c +++ b/drivers/spi/spi-altera.c @@ -43,6 +43,11 @@ #define ALTERA_SPI_MAX_CS 32 +enum altera_spi_type { + ALTERA_SPI_TYPE_UNKNOWN, + ALTERA_SPI_TYPE_SUBDEV, +}; + struct altera_spi { int irq; int len; @@ -55,6 +60,7 @@ struct altera_spi { unsigned char *rx; struct regmap *regmap; + u32 regoff; struct device *dev; }; @@ -70,7 +76,7 @@ static int altr_spi_writel(struct altera_spi *hw, unsigned int reg, { int ret; - ret = regmap_write(hw->regmap, reg, val); + ret = regmap_write(hw->regmap, hw->regoff + reg, val); if (ret) dev_err(hw->dev, "fail to write reg 0x%x val 0x%x: %d\n", reg, val, ret); @@ -83,7 +89,7 @@ static int altr_spi_readl(struct altera_spi *hw, unsigned int reg, { int ret; - ret = regmap_read(hw->regmap, reg, val); + ret = regmap_read(hw->regmap, hw->regoff + reg, val); if (ret) dev_err(hw->dev, "fail to read reg 0x%x: %d\n", reg, ret); @@ -225,10 +231,11 @@ static irqreturn_t altera_spi_irq(int irq, void *dev) static int altera_spi_probe(struct platform_device *pdev) { + const struct platform_device_id *platid = platform_get_device_id(pdev); struct altera_spi_platform_data *pdata = dev_get_platdata(&pdev->dev); + enum altera_spi_type type = ALTERA_SPI_TYPE_UNKNOWN; struct altera_spi *hw; struct spi_master *master; - void __iomem *res; int err = -ENODEV; u32 val; u16 i; @@ -264,19 +271,38 @@ static int altera_spi_probe(struct platform_device *pdev) hw = spi_master_get_devdata(master); hw->dev = &pdev->dev; + if (platid) + type = platid->driver_data; + /* find and map our resources */ - res = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(res)) { - err = PTR_ERR(res); - goto exit; - } + if (type == ALTERA_SPI_TYPE_SUBDEV) { + struct resource *regoff; - hw->regmap = devm_regmap_init_mmio(&pdev->dev, res, - &spi_altera_config); - if (IS_ERR(hw->regmap)) { - dev_err(&pdev->dev, "regmap mmio init failed\n"); - err = PTR_ERR(hw->regmap); - goto exit; + hw->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!hw->regmap) { + dev_err(&pdev->dev, "get regmap failed\n"); + goto exit; + } + + regoff = platform_get_resource(pdev, IORESOURCE_REG, 0); + if (regoff) + hw->regoff = regoff->start; + } else { + void __iomem *res; + + res = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(res)) { + err = PTR_ERR(res); + goto exit; + } + + hw->regmap = devm_regmap_init_mmio(&pdev->dev, res, + &spi_altera_config); + if (IS_ERR(hw->regmap)) { + dev_err(&pdev->dev, "regmap mmio init failed\n"); + err = PTR_ERR(hw->regmap); + goto exit; + } } /* program defaults into the registers */ @@ -308,7 +334,7 @@ static int altera_spi_probe(struct platform_device *pdev) } } - dev_info(&pdev->dev, "base %p, irq %d\n", res, hw->irq); + dev_info(&pdev->dev, "regoff %u, irq %d\n", hw->regoff, hw->irq); return 0; exit: @@ -325,6 +351,11 @@ static const struct of_device_id altera_spi_match[] = { MODULE_DEVICE_TABLE(of, altera_spi_match); #endif /* CONFIG_OF */ +static const struct platform_device_id altera_spi_ids[] = { + { "subdev_spi_altera", ALTERA_SPI_TYPE_SUBDEV }, + { } +}; + static struct platform_driver altera_spi_driver = { .probe = altera_spi_probe, .driver = { @@ -332,6 +363,7 @@ static struct platform_driver altera_spi_driver = { .pm = NULL, .of_match_table = of_match_ptr(altera_spi_match), }, + .id_table = altera_spi_ids, }; module_platform_driver(altera_spi_driver);