From patchwork Fri May 20 02:53:04 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Rich Felker X-Patchwork-Id: 9128561 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4D81960213 for ; Fri, 20 May 2016 02:54:44 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 40CA31FF29 for ; Fri, 20 May 2016 02:54:44 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 357622026B; Fri, 20 May 2016 02:54:44 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable 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 8EA381FF29 for ; Fri, 20 May 2016 02:54:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755800AbcETCyL (ORCPT ); Thu, 19 May 2016 22:54:11 -0400 Received: from 216-12-86-13.cv.mvl.ntelos.net ([216.12.86.13]:58093 "EHLO brightrain.aerifal.cx" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755671AbcETCxO (ORCPT ); Thu, 19 May 2016 22:53:14 -0400 Received: from dalias by brightrain.aerifal.cx with local (Exim 3.15 #2) id 1b3aYi-00071s-00; Fri, 20 May 2016 02:53:04 +0000 Message-Id: <2e287ca758002621ef8eed3db9df37678e26af5e.1463708766.git.dalias@libc.org> In-Reply-To: References: From: Rich Felker Subject: [PATCH v2 10/12] spi: add driver for J-Core SPI controller To: linux-kernel@vger.kernel.org, linux-sh@vger.kernel.org, linux-spi@vger.kernel.org Cc: Mark Brown Date: Fri, 20 May 2016 02:53:04 +0000 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 Signed-off-by: Rich Felker --- My previous post of the patch series accidentally omitted omitted Cc'ing of subsystem maintainers for the necessary clocksource, irqchip, and spi drivers. Please ack if this looks ok because I want to get it merged as part of the arch/sh pull request for 4.7. drivers/spi/Kconfig | 4 + drivers/spi/Makefile | 1 + drivers/spi/spi-jcore.c | 266 ++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 271 insertions(+) create mode 100644 drivers/spi/spi-jcore.c diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 9d8c84b..5bd2ccf 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -285,6 +285,10 @@ config SPI_IMX This enables using the Freescale i.MX SPI controllers in master mode. +config SPI_JCORE + tristate "J-Core SPI Master" + depends on OF + config SPI_LM70_LLP tristate "Parallel port adapter for LM70 eval board (DEVELOPMENT)" depends on PARPORT diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index fbb255c..6a34124 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -46,6 +46,7 @@ obj-$(CONFIG_SPI_FSL_SPI) += spi-fsl-spi.o obj-$(CONFIG_SPI_GPIO) += spi-gpio.o obj-$(CONFIG_SPI_IMG_SPFI) += spi-img-spfi.o obj-$(CONFIG_SPI_IMX) += spi-imx.o +obj-$(CONFIG_SPI_JCORE) += spi-jcore.o obj-$(CONFIG_SPI_LM70_LLP) += spi-lm70llp.o obj-$(CONFIG_SPI_LP8841_RTC) += spi-lp8841-rtc.o obj-$(CONFIG_SPI_MESON_SPIFC) += spi-meson-spifc.o diff --git a/drivers/spi/spi-jcore.c b/drivers/spi/spi-jcore.c new file mode 100644 index 0000000..552304c --- /dev/null +++ b/drivers/spi/spi-jcore.c @@ -0,0 +1,266 @@ +/* + * J-Core SPI controller driver + * + * Copyright (C) 2012-2016 SEI Inc. + * + * Current version by Rich Felker + * Based loosely on initial version by Oleksandr G Zhadan + * + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define USE_MESSAGE_MODE 1 + +#define DRV_NAME "jcore_spi" + +#define MAX_SPI_SPEED 12500000 /* 12.5 MHz */ + +#define CTRL_REG 0x0 +#define DATA_REG 0x4 + +#define SPI_NOCHIP_CS 0 +#define SPI_FLASH_CS 1 +#define SPI_CONF_CS 2 +#define SPI_SD_CS 2 +#define SPI_CODEC_CS 3 + +#define JCORE_SPI_CTRL_ACS 0x01 +#define JCORE_SPI_CTRL_XMIT 0x02 +#define JCORE_SPI_STAT_BUSY 0x02 +#define JCORE_SPI_CTRL_CCS 0x04 +#define JCORE_SPI_CTRL_LOOP 0x08 +#define JCORE_SPI_CTRL_DCS 0x10 + +#define JCORE_SPI_WAIT_RDY_MAX_LOOP 2000000 /* in usec */ + +struct jcore_spi { + struct spi_master *master; + void __iomem *base; + volatile unsigned int ctrlReg; + unsigned int csReg; + unsigned int speedReg; + unsigned int speed_hz; +}; + +static void jcore_spi_wait_till_ready(struct jcore_spi *hw, int timeout) +{ + while (timeout--) { + hw->ctrlReg = readl(hw->base + CTRL_REG); + if (!(hw->ctrlReg & JCORE_SPI_STAT_BUSY)) + return; + cpu_relax(); + } + pr_err("%s: Timeout..\n", __func__); +} + +static void jcore_spi_program(struct jcore_spi *hw) +{ + jcore_spi_wait_till_ready(hw, JCORE_SPI_WAIT_RDY_MAX_LOOP); + writel(hw->csReg | hw->speedReg, hw->base + CTRL_REG); +} + +static void jcore_spi_chipsel(struct spi_device *spi, bool value) +{ + struct jcore_spi *hw = spi_master_get_devdata(spi->master); + + pr_debug("%s: CS=%d\n", __func__, value); + + hw->csReg = ( JCORE_SPI_CTRL_ACS | JCORE_SPI_CTRL_CCS | JCORE_SPI_CTRL_DCS ) + ^ (!value << 2*spi->chip_select); + + jcore_spi_program(hw); +} + +static void jcore_spi_baudrate(struct jcore_spi *hw, int speed) +{ + if (speed == hw->speed_hz) return; + hw->speed_hz = speed; + hw->speedReg = ((MAX_SPI_SPEED / speed) - 1) << 27; + jcore_spi_program(hw); + pr_debug("%s: speed=%d pre=0x%x\n", __func__, speed, hw->speedReg); +} + +static int jcore_spi_txrx(struct spi_master *master, struct spi_device *spi, struct spi_transfer *t) +{ + struct jcore_spi *hw = spi_master_get_devdata(master); + + void *ctrl_reg = hw->base + CTRL_REG; + void *data_reg = hw->base + DATA_REG; + int timeout; + int xmit; + int status; + + /* data buffers */ + const unsigned char *tx; + unsigned char *rx; + int len; + int count; + + jcore_spi_baudrate(hw, t->speed_hz); + + xmit = hw->csReg | hw->speedReg | JCORE_SPI_CTRL_XMIT; + tx = t->tx_buf; + rx = t->rx_buf; + len = t->len; + + for (count = 0; count < len; count++) { + timeout = JCORE_SPI_WAIT_RDY_MAX_LOOP; + do status = readl(ctrl_reg); + while ((status & JCORE_SPI_STAT_BUSY) && --timeout); + if (!timeout) break; + + writel(tx ? *tx++ : 0, data_reg); + writel(xmit, ctrl_reg); + + timeout = JCORE_SPI_WAIT_RDY_MAX_LOOP; + do status = readl(ctrl_reg); + while ((status & JCORE_SPI_STAT_BUSY) && --timeout); + if (!timeout) break; + + if (rx) *rx++ = readl(data_reg); + } + +#if !USE_MESSAGE_MODE + spi_finalize_current_transfer(master); +#endif + + return countspi; + struct spi_transfer *xfer; + bool keep_cs = false; + int ret = 0; + + jcore_spi_chipsel(spi, false); + + list_for_each_entry(xfer, &msg->transfers, transfer_list) { + ret = jcore_spi_txrx(master, spi, xfer); + if (ret) break; + if (xfer->delay_usecs) + udelay(xfer->delay_usecs); + if (xfer->cs_change) { + if (list_is_last(&xfer->transfer_list, + &msg->transfers)) { + keep_cs = true; + } else { + jcore_spi_chipsel(spi, true); + udelay(10); + jcore_spi_chipsel(spi, false); + } + } + msg->actual_length += xfer->len; + } + + if (!keep_cs) + jcore_spi_chipsel(spi, true); + + msg->status = ret; + + spi_finalize_current_message(master); + + return ret; +} +#endif + +static int jcore_spi_probe(struct platform_device *pdev) +{ + struct device_node *node = pdev->dev.of_node; + struct jcore_spi *hw; + struct spi_master *master; + struct resource *res; + int err = -ENODEV; + + master = spi_alloc_master(&pdev->dev, sizeof(struct jcore_spi)); + if (!master) + return err; + + /* setup the master state. */ + master->num_chipselect = 3; + master->mode_bits = SPI_MODE_3; +#if USE_MESSAGE_MODE + master->transfer_one_message = jcore_spi_transfer_one_message; +#else + master->transfer_one = jcore_spi_txrx; +#endif + master->set_cs = jcore_spi_chipsel; + master->dev.of_node = node; + + hw = spi_master_get_devdata(master); + hw->master = master; + platform_set_drvdata(pdev, hw); + + /* find and map our resources */ + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (!res) + goto exit_busy; + if (!devm_request_mem_region + (&pdev->dev, res->start, resource_size(res), pdev->name)) + goto exit_busy; + hw->base = + devm_ioremap_nocache(&pdev->dev, res->start, resource_size(res)); + if (!hw->base) + goto exit_busy; + + jcore_spi_baudrate(hw, 400000); + + pdev->dev.dma_mask = 0; + /* register our spi controller */ + err = spi_register_master(master); + if (err) + goto exit; + dev_info(&pdev->dev, "base %p, noirq\n", hw->base); + + return 0; + +exit_busy: + err = -EBUSY; +exit: + platform_set_drvdata(pdev, NULL); + spi_master_put(master); + return err; +} + +static int jcore_spi_remove(struct platform_device *dev) +{ + struct jcore_spi *hw = platform_get_drvdata(dev); + struct spi_master *master = hw->master; + + platform_set_drvdata(dev, NULL); + spi_master_put(master); + return 0; +} + +static const struct of_device_id jcore_spi_of_match[] = { + { .compatible = "jcore,spi2" }, + {}, +}; + +static struct platform_driver jcore_spi_driver = { + .probe = jcore_spi_probe, + .remove = jcore_spi_remove, + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + .pm = NULL, + .of_match_table = jcore_spi_of_match, + }, +}; + +module_platform_driver(jcore_spi_driver); + +MODULE_DESCRIPTION("J-Core SPI driver"); +MODULE_AUTHOR("Rich Felker "); +MODULE_ALIAS("platform:" DRV_NAME);