From patchwork Fri Nov 12 19:50:38 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gabor Juhos X-Patchwork-Id: 320802 Received: from lists.sourceforge.net (lists.sourceforge.net [216.34.181.88]) by demeter1.kernel.org (8.14.4/8.14.3) with ESMTP id oACK8rdP004583 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Fri, 12 Nov 2010 20:09:15 GMT Received: from localhost ([127.0.0.1] helo=sfs-ml-1.v29.ch3.sourceforge.com) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.69) (envelope-from ) id 1PGzvS-0006Ph-SJ; Fri, 12 Nov 2010 20:08:46 +0000 Received: from sog-mx-4.v43.ch3.sourceforge.com ([172.29.43.194] helo=mx.sourceforge.net) by sfs-ml-1.v29.ch3.sourceforge.com with esmtp (Exim 4.69) (envelope-from ) id 1PGzvR-0006Pc-VJ for spi-devel-general@lists.sourceforge.net; Fri, 12 Nov 2010 20:08:45 +0000 X-ACL-Warn: Received: from phoenix3.szarvasnet.hu ([87.101.127.16]) by sog-mx-4.v43.ch3.sourceforge.com with esmtp (Exim 4.69) id 1PGzvN-0006I3-Js for spi-devel-general@lists.sourceforge.net; Fri, 12 Nov 2010 20:08:45 +0000 Received: from mail.szarvas.hu (localhost [127.0.0.1]) by phoenix3.szarvasnet.hu (Postfix) with SMTP id 75EA745C007; Fri, 12 Nov 2010 20:50:50 +0100 (CET) Received: from localhost.localdomain (catvpool-576570d8.szarvasnet.hu [87.101.112.216]) by phoenix3.szarvasnet.hu (Postfix) with ESMTP id B09B91F0002; Fri, 12 Nov 2010 20:50:49 +0100 (CET) From: Gabor Juhos To: Ralf Baechle Subject: [RFC 11/18] spi: add SPI controller driver for the Atheros AR71XX/AR724X/AR913X SoCs Date: Fri, 12 Nov 2010 20:50:38 +0100 Message-Id: <1289591445-28842-12-git-send-email-juhosg@openwrt.org> X-Mailer: git-send-email 1.7.2.1 In-Reply-To: <1289591445-28842-1-git-send-email-juhosg@openwrt.org> References: <1289591445-28842-1-git-send-email-juhosg@openwrt.org> X-VBMS: A1583301132 | phoenix3 | 127.0.0.1 | | | X-Spam-Score: 0.0 (/) X-Spam-Report: Spam Filtering performed by mx.sourceforge.net. 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X-Headers-End: 1PGzvN-0006I3-Js Cc: Gabor Juhos , kaloz@openwrt.org, David Brownell , spi-devel-general@lists.sourceforge.net X-BeenThere: spi-devel-general@lists.sourceforge.net X-Mailman-Version: 2.1.9 Precedence: list List-Id: Linux SPI core/device drivers discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: spi-devel-general-bounces@lists.sourceforge.net X-Greylist: IP, sender and recipient auto-whitelisted, not delayed by milter-greylist-4.2.3 (demeter1.kernel.org [140.211.167.41]); Fri, 12 Nov 2010 20:09:15 +0000 (UTC) diff --git a/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h b/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h new file mode 100644 index 0000000..aa71216 --- /dev/null +++ b/arch/mips/include/asm/mach-ath79/ath79_spi_platform.h @@ -0,0 +1,19 @@ +/* + * Platform data definition for Atheros AR71XX/AR724X/AR913X SPI controller + * + * Copyright (C) 2008-2010 Gabor Juhos + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. + */ + +#ifndef _ATH79_SPI_PLATFORM_H +#define _ATH79_SPI_PLATFORM_H + +struct ath79_spi_platform_data { + unsigned bus_num; + unsigned num_chipselect; +}; + +#endif /* _ATH79_SPI_PLATFORM_H */ diff --git a/drivers/spi/Kconfig b/drivers/spi/Kconfig index 78f9fd0..f2093e1 100644 --- a/drivers/spi/Kconfig +++ b/drivers/spi/Kconfig @@ -53,6 +53,14 @@ if SPI_MASTER comment "SPI Master Controller Drivers" +config SPI_ATH79 + tristate "Atheros AR71XX/AR724X/AR913X SPI controller driver" + depends on ATH79 && GENERIC_GPIO + select SPI_BITBANG + help + This enables support for the SPI controller present on the + Atheros AR71XX/AR724X/AR913X SoCs. + config SPI_ATMEL tristate "Atmel SPI Controller" depends on (ARCH_AT91 || AVR32) diff --git a/drivers/spi/Makefile b/drivers/spi/Makefile index 8bc1a5a..875bc3d 100644 --- a/drivers/spi/Makefile +++ b/drivers/spi/Makefile @@ -10,6 +10,7 @@ obj-$(CONFIG_SPI_MASTER) += spi.o # SPI master controller drivers (bus) obj-$(CONFIG_SPI_ATMEL) += atmel_spi.o +obj-$(CONFIG_SPI_ATH79) += ath79_spi.o obj-$(CONFIG_SPI_BFIN) += spi_bfin5xx.o obj-$(CONFIG_SPI_BITBANG) += spi_bitbang.o obj-$(CONFIG_SPI_AU1550) += au1550_spi.o diff --git a/drivers/spi/ath79_spi.c b/drivers/spi/ath79_spi.c new file mode 100644 index 0000000..9b9f9cf --- /dev/null +++ b/drivers/spi/ath79_spi.c @@ -0,0 +1,291 @@ +/* + * SPI controller driver for the Atheros AR71XX/AR724X/AR913X SoCs + * + * Copyright (C) 2009-2010 Gabor Juhos + * + * This driver has been based on the spi-gpio.c: + * Copyright (C) 2006,2008 David Brownell + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +#define DRV_DESC "SPI controller driver for Atheros AR71XX/AR724X/AR91X" +#define DRV_NAME "ath79-spi" + +struct ath79_spi { + struct spi_bitbang bitbang; + u32 ioc_base; + u32 reg_ctrl; + + void __iomem *base; + + struct platform_device *pdev; +}; + +static inline u32 ath79_spi_rr(struct ath79_spi *sp, unsigned reg) +{ + return __raw_readl(sp->base + reg); +} + +static inline void ath79_spi_wr(struct ath79_spi *sp, unsigned reg, u32 val) +{ + __raw_writel(val, sp->base + reg); +} + +static inline struct ath79_spi *spidev_to_sp(struct spi_device *spi) +{ + return spi_master_get_devdata(spi->master); +} + +static void ath79_spi_chipselect(struct spi_device *spi, int is_active) +{ + struct ath79_spi *sp = spidev_to_sp(spi); + int cs_high = (spi->mode & SPI_CS_HIGH) ? is_active : !is_active; + + if (is_active) { + /* set initial clock polarity */ + if (spi->mode & SPI_CPOL) + sp->ioc_base |= AR71XX_SPI_IOC_CLK; + else + sp->ioc_base &= ~AR71XX_SPI_IOC_CLK; + + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base); + } + + if (spi->chip_select) { + unsigned long gpio = (unsigned long) spi->controller_data; + + /* SPI is normally active-low */ + gpio_set_value(gpio, cs_high); + } else { + if (cs_high) + sp->ioc_base |= AR71XX_SPI_IOC_CS0; + else + sp->ioc_base &= ~AR71XX_SPI_IOC_CS0; + + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base); + } + +} + +static int ath79_spi_setup_cs(struct spi_device *spi) +{ + struct ath79_spi *sp = spidev_to_sp(spi); + + /* enable GPIO mode */ + ath79_spi_wr(sp, AR71XX_SPI_REG_FS, AR71XX_SPI_FS_GPIO); + + /* save CTRL register */ + sp->reg_ctrl = ath79_spi_rr(sp, AR71XX_SPI_REG_CTRL); + sp->ioc_base = ath79_spi_rr(sp, AR71XX_SPI_REG_IOC); + + /* TODO: setup speed? */ + ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, 0x43); + + if (spi->chip_select) { + unsigned long gpio = (unsigned long) spi->controller_data; + int status = 0; + + status = gpio_request(gpio, dev_name(&spi->dev)); + if (status) + return status; + + status = gpio_direction_output(gpio, spi->mode & SPI_CS_HIGH); + if (status) { + gpio_free(gpio); + return status; + } + } else { + if (spi->mode & SPI_CS_HIGH) + sp->ioc_base |= AR71XX_SPI_IOC_CS0; + else + sp->ioc_base &= ~AR71XX_SPI_IOC_CS0; + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, sp->ioc_base); + } + + return 0; +} + +static void ath79_spi_cleanup_cs(struct spi_device *spi) +{ + struct ath79_spi *sp = spidev_to_sp(spi); + + if (spi->chip_select) { + unsigned long gpio = (unsigned long) spi->controller_data; + gpio_free(gpio); + } + + /* restore CTRL register */ + ath79_spi_wr(sp, AR71XX_SPI_REG_CTRL, sp->reg_ctrl); + /* disable GPIO mode */ + ath79_spi_wr(sp, AR71XX_SPI_REG_FS, 0); +} + +static int ath79_spi_setup(struct spi_device *spi) +{ + int status = 0; + + if (spi->bits_per_word > 32) + return -EINVAL; + + if (!spi->controller_state) { + status = ath79_spi_setup_cs(spi); + if (status) + return status; + } + + status = spi_bitbang_setup(spi); + if (status && !spi->controller_state) + ath79_spi_cleanup_cs(spi); + + return status; +} + +static void ath79_spi_cleanup(struct spi_device *spi) +{ + ath79_spi_cleanup_cs(spi); + spi_bitbang_cleanup(spi); +} + +static u32 ath79_spi_txrx_mode0(struct spi_device *spi, unsigned nsecs, + u32 word, u8 bits) +{ + struct ath79_spi *sp = spidev_to_sp(spi); + u32 ioc = sp->ioc_base; + + /* clock starts at inactive polarity */ + for (word <<= (32 - bits); likely(bits); bits--) { + u32 out; + + if (word & (1 << 31)) + out = ioc | AR71XX_SPI_IOC_DO; + else + out = ioc & ~AR71XX_SPI_IOC_DO; + + /* setup MSB (to slave) on trailing edge */ + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out); + ath79_spi_wr(sp, AR71XX_SPI_REG_IOC, out | AR71XX_SPI_IOC_CLK); + + word <<= 1; + } + + return ath79_spi_rr(sp, AR71XX_SPI_REG_RDS); +} + +static int ath79_spi_probe(struct platform_device *pdev) +{ + struct spi_master *master; + struct ath79_spi *sp; + struct ath79_spi_platform_data *pdata; + struct resource *r; + int ret; + + master = spi_alloc_master(&pdev->dev, sizeof(*sp)); + if (master == NULL) { + dev_err(&pdev->dev, "failed to allocate spi master\n"); + return -ENOMEM; + } + + sp = spi_master_get_devdata(master); + platform_set_drvdata(pdev, sp); + + pdata = pdev->dev.platform_data; + + master->setup = ath79_spi_setup; + master->cleanup = ath79_spi_cleanup; + if (pdata) { + master->bus_num = pdata->bus_num; + master->num_chipselect = pdata->num_chipselect; + } else { + master->bus_num = 0; + master->num_chipselect = 1; + } + + sp->bitbang.master = spi_master_get(master); + sp->bitbang.chipselect = ath79_spi_chipselect; + sp->bitbang.txrx_word[SPI_MODE_0] = ath79_spi_txrx_mode0; + sp->bitbang.setup_transfer = spi_bitbang_setup_transfer; + sp->bitbang.flags = SPI_CS_HIGH; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + if (r == NULL) { + ret = -ENOENT; + goto err_put_master; + } + + sp->base = ioremap(r->start, r->end - r->start + 1); + if (!sp->base) { + ret = -ENXIO; + goto err_put_master; + } + + ret = spi_bitbang_start(&sp->bitbang); + if (ret) + goto err_unmap; + + return 0; + +err_unmap: + iounmap(sp->base); +err_put_master: + platform_set_drvdata(pdev, NULL); + spi_master_put(sp->bitbang.master); + + return ret; +} + +static int ath79_spi_remove(struct platform_device *pdev) +{ + struct ath79_spi *sp = platform_get_drvdata(pdev); + + spi_bitbang_stop(&sp->bitbang); + iounmap(sp->base); + platform_set_drvdata(pdev, NULL); + spi_master_put(sp->bitbang.master); + + return 0; +} + +static struct platform_driver ath79_spi_drv = { + .probe = ath79_spi_probe, + .remove = ath79_spi_remove, + .driver = { + .name = DRV_NAME, + .owner = THIS_MODULE, + }, +}; + +static int __init ath79_spi_init(void) +{ + return platform_driver_register(&ath79_spi_drv); +} +module_init(ath79_spi_init); + +static void __exit ath79_spi_exit(void) +{ + platform_driver_unregister(&ath79_spi_drv); +} +module_exit(ath79_spi_exit); + +MODULE_DESCRIPTION(DRV_DESC); +MODULE_AUTHOR("Gabor Juhos "); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:" DRV_NAME);