From patchwork Thu Jun 11 03:25:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xu Yilun X-Patchwork-Id: 11599165 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 BB4F6159A for ; Thu, 11 Jun 2020 03:29:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A21DF2064C for ; Thu, 11 Jun 2020 03:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726560AbgFKD3D (ORCPT ); Wed, 10 Jun 2020 23:29:03 -0400 Received: from mga18.intel.com ([134.134.136.126]:28223 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726552AbgFKD3B (ORCPT ); Wed, 10 Jun 2020 23:29:01 -0400 IronPort-SDR: Y5uFRdSm/lfwTCjWKjW+/rK5nwiVg1pkoBX26B6ZlOUMfcGrDwWkZtsJ+7DhZDdNcFZAaDH3So 1TGX8VsgXuog== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 10 Jun 2020 20:29:01 -0700 IronPort-SDR: UurW9DTzlZhB2JIUe3MsyFd0c3yEH4XHODltdbr8lz7FrbRxiT4fCNd09v/g4cfNF9KRi1Pl9O EVugpzfL8wNw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.73,498,1583222400"; d="scan'208";a="260587374" Received: from yilunxu-optiplex-7050.sh.intel.com ([10.239.159.141]) by fmsmga008.fm.intel.com with ESMTP; 10 Jun 2020 20:28:59 -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: [PATCH 4/6] spi: altera: use regmap instead of direct mmio register access Date: Thu, 11 Jun 2020 11:25:09 +0800 Message-Id: <1591845911-10197-5-git-send-email-yilun.xu@intel.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1591845911-10197-1-git-send-email-yilun.xu@intel.com> References: <1591845911-10197-1-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 regmap. It allows this driver to be compatible if low layer register access method is changed in some cases. Signed-off-by: Matthew Gerlach Signed-off-by: Wu Hao Signed-off-by: Xu Yilun Signed-off-by: Russ Weight --- drivers/spi/Kconfig | 1 + drivers/spi/spi-altera.c | 103 ++++++++++++++++++++++++++++++++++++--------- include/linux/spi/altera.h | 6 +++ 3 files changed, 90 insertions(+), 20 deletions(-) diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 8f1f8fc..6d79fc7 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -59,6 +59,7 @@ comment "SPI Master Controller Drivers" config SPI_ALTERA tristate "Altera SPI Controller" + select REGMAP_MMIO help This is the driver for the Altera SPI Controller. diff --git a/drivers/spi/spi-altera.c b/drivers/spi/spi-altera.c index aa9d1a2..8d47c57 100644 --- a/drivers/spi/spi-altera.c +++ b/drivers/spi/spi-altera.c @@ -44,7 +44,6 @@ #define ALTERA_SPI_MAX_CS 32 struct altera_spi { - void __iomem *base; int irq; int len; int count; @@ -54,8 +53,45 @@ struct altera_spi { /* data buffers */ const unsigned char *tx; unsigned char *rx; + + struct regmap *regmap; + u32 base; + + struct device *dev; +}; + +static const struct regmap_config spi_altera_config = { + .reg_bits = 32, + .reg_stride = 4, + .val_bits = 32, + .fast_io = true, }; +static int altr_spi_writel(struct altera_spi *hw, unsigned int reg, + unsigned int val) +{ + int ret; + + ret = regmap_write(hw->regmap, hw->base + reg, val); + if (ret) + dev_err(hw->dev, "fail to write reg 0x%x val 0x%x: %d\n", + reg, val, ret); + + return ret; +} + +static int altr_spi_readl(struct altera_spi *hw, unsigned int reg, + unsigned int *val) +{ + int ret; + + ret = regmap_read(hw->regmap, hw->base + reg, val); + if (ret) + dev_err(hw->dev, "fail to read reg 0x%x: %d\n", reg, ret); + + return ret; +} + static inline struct altera_spi *altera_spi_to_hw(struct spi_device *sdev) { return spi_master_get_devdata(sdev->master); @@ -67,12 +103,13 @@ static void altera_spi_set_cs(struct spi_device *spi, bool is_high) if (is_high) { hw->imr &= ~ALTERA_SPI_CONTROL_SSO_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); - writel(0, hw->base + ALTERA_SPI_SLAVE_SEL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); + altr_spi_writel(hw, ALTERA_SPI_SLAVE_SEL, 0); } else { - writel(BIT(spi->chip_select), hw->base + ALTERA_SPI_SLAVE_SEL); + altr_spi_writel(hw, ALTERA_SPI_SLAVE_SEL, + BIT(spi->chip_select)); hw->imr |= ALTERA_SPI_CONTROL_SSO_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); } } @@ -99,14 +136,14 @@ static void altera_spi_tx_word(struct altera_spi *hw) } } - writel(txd, hw->base + ALTERA_SPI_TXDATA); + altr_spi_writel(hw, ALTERA_SPI_TXDATA, txd); } static void altera_spi_rx_word(struct altera_spi *hw) { unsigned int rxd; - rxd = readl(hw->base + ALTERA_SPI_RXDATA); + altr_spi_readl(hw, ALTERA_SPI_RXDATA, &rxd); if (hw->rx) { switch (hw->bytes_per_word) { case 1: @@ -133,6 +170,7 @@ static int altera_spi_txrx(struct spi_master *master, struct spi_device *spi, struct spi_transfer *t) { struct altera_spi *hw = spi_master_get_devdata(master); + u32 val; hw->tx = t->tx_buf; hw->rx = t->rx_buf; @@ -143,7 +181,7 @@ static int altera_spi_txrx(struct spi_master *master, if (hw->irq >= 0) { /* enable receive interrupt */ hw->imr |= ALTERA_SPI_CONTROL_IRRDY_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); /* send the first byte */ altera_spi_tx_word(hw); @@ -151,9 +189,13 @@ static int altera_spi_txrx(struct spi_master *master, while (hw->count < hw->len) { altera_spi_tx_word(hw); - while (!(readl(hw->base + ALTERA_SPI_STATUS) & - ALTERA_SPI_STATUS_RRDY_MSK)) + for (;;) { + altr_spi_readl(hw, ALTERA_SPI_STATUS, &val); + if (val & ALTERA_SPI_STATUS_RRDY_MSK) + break; + cpu_relax(); + } altera_spi_rx_word(hw); } @@ -175,7 +217,7 @@ static irqreturn_t altera_spi_irq(int irq, void *dev) } else { /* disable receive interrupt */ hw->imr &= ~ALTERA_SPI_CONTROL_IRRDY_MSK; - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); spi_finalize_current_transfer(master); } @@ -188,7 +230,9 @@ static int altera_spi_probe(struct platform_device *pdev) struct altera_spi_platform_data *pdata = dev_get_platdata(&pdev->dev); struct altera_spi *hw; struct spi_master *master; + void __iomem *res; int err = -ENODEV; + u32 val; u16 i; master = spi_alloc_master(&pdev->dev, sizeof(struct altera_spi)); @@ -220,19 +264,38 @@ static int altera_spi_probe(struct platform_device *pdev) master->set_cs = altera_spi_set_cs; hw = spi_master_get_devdata(master); + hw->dev = &pdev->dev; /* find and map our resources */ - hw->base = devm_platform_ioremap_resource(pdev, 0); - if (IS_ERR(hw->base)) { - err = PTR_ERR(hw->base); - goto exit; + if (pdata && pdata->use_parent_regmap) { + hw->regmap = dev_get_regmap(pdev->dev.parent, NULL); + if (!hw->regmap) { + dev_err(&pdev->dev, "get regmap failed\n"); + goto exit; + } + hw->base = pdata->regoff; + } else { + 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 */ hw->imr = 0; /* disable spi interrupts */ - writel(hw->imr, hw->base + ALTERA_SPI_CONTROL); - writel(0, hw->base + ALTERA_SPI_STATUS); /* clear status reg */ - if (readl(hw->base + ALTERA_SPI_STATUS) & ALTERA_SPI_STATUS_RRDY_MSK) - readl(hw->base + ALTERA_SPI_RXDATA); /* flush rxdata */ + altr_spi_writel(hw, ALTERA_SPI_CONTROL, hw->imr); + altr_spi_writel(hw, ALTERA_SPI_STATUS, 0); /* clear status reg */ + altr_spi_readl(hw, ALTERA_SPI_STATUS, &val); + if (val & ALTERA_SPI_STATUS_RRDY_MSK) + altr_spi_readl(hw, ALTERA_SPI_RXDATA, &val); /* flush rxdata */ /* irq is optional */ hw->irq = platform_get_irq(pdev, 0); if (hw->irq >= 0) { @@ -255,7 +318,7 @@ static int altera_spi_probe(struct platform_device *pdev) } } - dev_info(&pdev->dev, "base %p, irq %d\n", hw->base, hw->irq); + dev_info(&pdev->dev, "base %u, irq %d\n", hw->base, hw->irq); return 0; exit: diff --git a/include/linux/spi/altera.h b/include/linux/spi/altera.h index 2d42641..164ab7b 100644 --- a/include/linux/spi/altera.h +++ b/include/linux/spi/altera.h @@ -17,6 +17,10 @@ * @num_devices: Number of devices that shall be added when the driver * is probed. * @devices: The devices to add. + * @use_parent_regmap: If true, device uses parent regmap to access its + * registers. Otherwise try map platform mmio resources. + * @regoff: Offset of the device register base in parent regmap. + * This field is ignored when use_parent_regmap == false. */ struct altera_spi_platform_data { u16 mode_bits; @@ -24,6 +28,8 @@ struct altera_spi_platform_data { u32 bits_per_word_mask; u16 num_devices; struct spi_board_info *devices; + bool use_parent_regmap; + u32 regoff; }; #endif /* __LINUX_SPI_ALTERA_H */