From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from s1.linux-source.de ([46.38.235.25]) by bombadil.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1XMvi5-0002fM-BF for barebox@lists.infradead.org; Thu, 28 Aug 2014 09:09:38 +0000 Received: from localhost (localhost [127.0.0.1]) by s1.linux-source.de (Postfix) with ESMTP id 9AC081808DC for ; Thu, 28 Aug 2014 10:59:52 +0200 (CEST) Received: from s1.linux-source.de ([127.0.0.1]) by localhost (v22010076022355399.yourvserver.net [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 0TV7qy8RD__r for ; Thu, 28 Aug 2014 10:59:51 +0200 (CEST) MIME-Version: 1.0 Date: Thu, 28 Aug 2014 10:59:51 +0200 From: basti@linux-source.de Message-ID: <98034ceb4fe0a107abef0beb3fd1380c@linux-source.de> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: [PATCH] mtd: add mtdram device (which build mtd over ram area - useful for FRAM oder MRAM) To: barebox@lists.infradead.org This adds support for MTD in RAM devices (like FRAM or MRAM). Signed-off-by: Sebastian Block --- drivers/mtd/devices/Kconfig | 6 ++ drivers/mtd/devices/Makefile | 1 + drivers/mtd/devices/mtdram.c | 132 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 139 insertions(+) create mode 100644 drivers/mtd/devices/mtdram.c diff --git a/drivers/mtd/devices/Kconfig b/drivers/mtd/devices/Kconfig index 94668a2..c512242 100644 --- a/drivers/mtd/devices/Kconfig +++ b/drivers/mtd/devices/Kconfig @@ -64,4 +64,10 @@ config MTD_DOCG3 M-Systems and now Sandisk. The support is very experimental, and doesn't give access to any write operations. +config MTD_MTDRAM + tristate "Provide test driver using RAM" + help + This enables a test MTD device driver which uses RAM to + provide storage. + endmenu diff --git a/drivers/mtd/devices/Makefile b/drivers/mtd/devices/Makefile index bf1f8a9..bc1960e 100644 --- a/drivers/mtd/devices/Makefile +++ b/drivers/mtd/devices/Makefile @@ -5,3 +5,4 @@ obj-$(CONFIG_MTD_DATAFLASH) += mtd_dataflash.o obj-$(CONFIG_MTD_DOCG3) += docg3.o obj-$(CONFIG_MTD_M25P80) += m25p80.o +obj-$(CONFIG_MTD_MTDRAM) += mtdram.o diff --git a/drivers/mtd/devices/mtdram.c b/drivers/mtd/devices/mtdram.c new file mode 100644 index 0000000..bd0bbb4 --- /dev/null +++ b/drivers/mtd/devices/mtdram.c @@ -0,0 +1,132 @@ +/* + * MTD RAM driver - a mtd test device driver + * + * Author: Sebastian Block + * Copyright (c) 2014 + * + * Some parts are based on mtdram.c found in Linux kernel + * by Alexander Larsson + * and Joern Engel . + * + * This code 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 + +struct mtdram_priv_data { + struct mtd_info mtd; + void *base; +}; + +static int ram_erase(struct mtd_info *mtd, struct erase_info *instr) { + memset((char *)mtd->priv + instr->addr, 0xff, instr->len); + instr->state = MTD_ERASE_DONE; + mtd_erase_callback(instr); + return 0; +} + +static int ram_write(struct mtd_info *mtd, loff_t to, size_t len, + size_t *retlen, const u_char *buf) { + memcpy((char*)mtd->priv + to, buf, len); + *retlen = len; + return 0; +} + +static int ram_read(struct mtd_info *mtd, loff_t from, size_t len, + size_t *retlen, u_char *buf) { + memcpy(buf, mtd->priv + from, len); + *retlen = len; + return 0; +} + +static int mtdram_probe(struct device_d *dev) { + void __iomem *base; + int device_id; + struct mtd_info *mtd; + struct resource *res; + loff_t size; + int ret = 0; + + + mtd = kzalloc(sizeof(struct mtd_info), GFP_KERNEL); + if (!mtd) { + ret = -ENOMEM; + goto nomem1; + } + + device_id = DEVICE_ID_SINGLE; + if (dev->device_node) { + const char *alias = of_alias_get(dev->device_node); + dev_info (dev, "is alias for %s\n", alias); + if (alias) + mtd->name = xstrdup(alias); + } + + if (!mtd->name) { + device_id = DEVICE_ID_DYNAMIC; + mtd->name = "mtdram"; + } + + dev_info(dev, "MTDRAM: probe for %s (dev_name=%s)\n", dev->name, mtd->name); + + base = dev_request_mem_region(dev, 0); + if (!base) { + ret = -EBUSY; + goto nobase; + } + + res = dev_get_resource(dev, IORESOURCE_MEM, 0); + size = (unsigned long) resource_size(res); + mtd->priv = base; + + mtd->type = MTD_RAM; + mtd->writesize = 1; + mtd->writebufsize = 64; + mtd->flags = MTD_CAP_RAM; + mtd->size = size; + + mtd->read = ram_read; + mtd->write = ram_write; + mtd->erase = ram_erase; + mtd->erasesize = 1; + + mtd->parent = dev; + + dev_info(dev, "add MTDRAM with size=%llx @%p\n", mtd->size, mtd->priv); + ret = add_mtd_device(mtd, mtd->name, device_id); + dev_info(dev, "MTDRAM: add_mtd_dev ret: %d\n", ret); + return ret; + +nobase: + kfree(mtd); +nomem1: + return ret; +} + +static __maybe_unused struct of_device_id mtdram_dt_ids[] = { + { + .compatible = "mtd-ram", + }, { + /* sentinel */ + } +}; + +static struct driver_d mtdram_driver = { + .name = "mtdram", + .probe = mtdram_probe, + .of_compatible = DRV_OF_COMPAT(mtdram_dt_ids), +}; +device_platform_driver(mtdram_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Sebastian Block"); +MODULE_DESCRIPTION("MTD RAM test driver"); -- 1.7.10.4 _______________________________________________ barebox mailing list barebox@lists.infradead.org http://lists.infradead.org/mailman/listinfo/barebox