From 99f2a8aea18c9779c141050c6f95a8f1da63bbe4 Mon Sep 17 00:00:00 2001 From: Ben Dooks Date: Mon, 24 Jan 2005 00:37:04 +0000 Subject: [PATCH] [MTD] Platform RAM Driver Driver for generic RAM blocks which are exported by an platform_device from the device driver system. Signed-off-by: Ben Dooks Signed-off-by: Thomas Gleixner --- drivers/mtd/maps/Kconfig | 12 +- drivers/mtd/maps/Makefile | 3 +- drivers/mtd/maps/plat-ram.c | 286 +++++++++++++++++++++++++++++++++++ include/linux/mtd/plat-ram.h | 35 +++++ 4 files changed, 334 insertions(+), 2 deletions(-) create mode 100644 drivers/mtd/maps/plat-ram.c create mode 100644 include/linux/mtd/plat-ram.h diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig index 8480057eadb4..7d21d432f380 100644 --- a/drivers/mtd/maps/Kconfig +++ b/drivers/mtd/maps/Kconfig @@ -1,5 +1,5 @@ # drivers/mtd/maps/Kconfig -# $Id: Kconfig,v 1.42 2005/01/05 16:59:50 dwmw2 Exp $ +# $Id: Kconfig,v 1.43 2005/01/24 00:35:21 bjd Exp $ menu "Mapping drivers for chip access" depends on MTD!=n @@ -659,5 +659,15 @@ config MTD_SHARP_SL help This enables access to the flash chip on the Sharp SL Series of PDAs. +config MTD_PLATRAM + tristate "Map driver for platfrom device RAM (mtd-ram)" + depends on MTD + select MTD_RAM + help + Map driver for RAM areas described via the platform device + system. + + This selection automatically selects the map_ram driver. + endmenu diff --git a/drivers/mtd/maps/Makefile b/drivers/mtd/maps/Makefile index 7ffe02b85301..d2e6dcc87059 100644 --- a/drivers/mtd/maps/Makefile +++ b/drivers/mtd/maps/Makefile @@ -1,7 +1,7 @@ # # linux/drivers/maps/Makefile # -# $Id: Makefile.common,v 1.23 2005/01/05 17:06:36 dwmw2 Exp $ +# $Id: Makefile.common,v 1.24 2005/01/24 00:35:21 bjd Exp $ ifeq ($(CONFIG_MTD_COMPLEX_MAPPINGS),y) obj-$(CONFIG_MTD) += map_funcs.o @@ -71,3 +71,4 @@ obj-$(CONFIG_MTD_IXP2000) += ixp2000.o obj-$(CONFIG_MTD_WRSBC8260) += wr_sbc82xx_flash.o obj-$(CONFIG_MTD_DMV182) += dmv182.o obj-$(CONFIG_MTD_SHARP_SL) += sharpsl-flash.o +obj-$(CONFIG_MTD_PLATRAM) += plat-ram.o diff --git a/drivers/mtd/maps/plat-ram.c b/drivers/mtd/maps/plat-ram.c new file mode 100644 index 000000000000..808f94346add --- /dev/null +++ b/drivers/mtd/maps/plat-ram.c @@ -0,0 +1,286 @@ +/* drivers/mtd/maps/plat-ram.c + * + * (c) 2004-2005 Simtec Electronics + * http://www.simtec.co.uk/products/SWLINUX/ + * Ben Dooks + * + * Generic platfrom device based RAM map + * + * $Id: plat-ram.c,v 1.1 2005/01/24 00:37:02 bjd Exp $ + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA +*/ + +#define DEBUG + +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include +#include + +#include + +/* private structure for each mtd platform ram device created */ + +struct platram_info { + struct device *dev; + struct mtd_info *mtd; + struct map_info map; + struct mtd_partition *partitions; + struct resource *area; + struct platdata_mtd_ram *pdata; +}; + +/* to_platram_info() + * + * device private data to struct platram_info conversion +*/ + +static inline struct platram_info *to_platram_info(struct device *dev) +{ + return (struct platram_info *)dev_get_drvdata(dev); +} + +/* platram_setrw + * + * call the platform device's set rw/ro control + * + * to = 0 => read-only + * = 1 => read-write +*/ + +static inline void platram_setrw(struct platram_info *info, int to) +{ + if (info->pdata == NULL) + return; + + if (info->pdata->set_rw != NULL) + (info->pdata->set_rw)(info->dev, to); +} + +/* platram_remove + * + * called to remove the device from the driver's control +*/ + +static int platram_remove(struct device *dev) +{ + struct platram_info *info = to_platram_info(dev); + + dev_set_drvdata(dev, NULL); + + dev_dbg(dev, "removing device\n"); + + if (info == NULL) + return 0; + + if (info->mtd) { +#ifdef CONFIG_MTD_PARTITIONS + if (info->partitions) { + del_mtd_partitions(info->mtd); + kfree(info->partitions); + } +#endif + del_mtd_device(info->mtd); + map_destroy(info->mtd); + } + + /* ensure ram is left read-only */ + + platram_setrw(info, PLATRAM_RO); + + /* release resources */ + + if (info->area) { + release_resource(info->area); + kfree(info->area); + } + + if (info->map.virt != NULL) + iounmap(info->map.virt); + + kfree(info); + + return 0; +} + +/* platram_probe + * + * called from device drive system when a device matching our + * driver is found. +*/ + +static int platram_probe(struct device *dev) +{ + struct platform_device *pd = to_platform_device(dev); + struct platdata_mtd_ram *pdata; + struct platram_info *info; + struct resource *res; + int err = 0; + + dev_dbg(dev, "probe entered\n"); + + if (dev->platform_data == NULL) { + dev_err(dev, "no platform data supplied\n"); + err = -ENOENT; + goto exit_error; + } + + pdata = dev->platform_data; + + info = kmalloc(sizeof(*info), GFP_KERNEL); + if (info == NULL) { + dev_err(dev, "no memory for flash info\n"); + err = -ENOMEM; + goto exit_error; + } + + memzero(info, sizeof(*info)); + dev_set_drvdata(dev, info); + + info->dev = dev; + info->pdata = pdata; + + /* get the resource for the memory mapping */ + + res = platform_get_resource(pd, IORESOURCE_MEM, 0); + + if (res == NULL) { + dev_err(dev, "no memory resource specified\n"); + err = -ENOENT; + goto exit_free; + } + + dev_dbg(dev, "got platform resource %p (0x%lx)\n", res, res->start); + + /* setup map parameters */ + + info->map.phys = res->start; + info->map.size = (res->end - res->start) + 1; + info->map.name = pdata->mapname != NULL ? pdata->mapname : pd->name; + info->map.bankwidth = pdata->bankwidth; + + /* register our usage of the memory area */ + + info->area = request_mem_region(res->start, info->map.size, pd->name); + if (info->area == NULL) { + dev_err(dev, "failed to request memory region\n"); + err = -EIO; + goto exit_free; + } + + /* remap the memory area */ + + info->map.virt = ioremap(res->start, info->map.size); + dev_dbg(dev, "virt %p, %d bytes\n", info->map.virt, info->map.size); + + if (info->map.virt == NULL) { + dev_err(dev, "failed to ioremap() region\n"); + err = -EIO; + goto exit_free; + } + + { + unsigned int *p = (unsigned int *)info->map.virt; + printk("%08x %08x %08x %08x\n", + readl(p), readl(p+1), readl(p+2), readl(p+3)); + } + + simple_map_init(&info->map); + + dev_dbg(dev, "initialised map, probing for mtd\n"); + + /* probe for the right mtd map driver */ + + info->mtd = do_map_probe("map_ram" , &info->map); + if (info->mtd == NULL) { + dev_err(dev, "failed to probe for map_ram\n"); + err = -ENOMEM; + goto exit_free; + } + + info->mtd->owner = THIS_MODULE; + + platram_setrw(info, PLATRAM_RW); + + /* check to see if there are any available partitions, or wether + * to add this device whole */ + +#ifdef CONFIG_MTD_PARTITIONS + if (pdata->nr_partitions > 0) { + const char **probes = { NULL }; + + if (pdata->probes) + probes = (const char **)pdata->probes; + + err = parse_mtd_partitions(info->mtd, probes, + &info->partitions, 0); + if (err > 0) { + err = add_mtd_partitions(info->mtd, info->partitions, + err); + } + } +#endif /* CONFIG_MTD_PARTITIONS */ + + if (add_mtd_device(info->mtd)) { + dev_err(dev, "add_mtd_device() failed\n"); + err = -ENOMEM; + } + + dev_info(dev, "registered mtd device\n"); + return err; + + exit_free: + platram_remove(dev); + exit_error: + return err; +} + +/* device driver info */ + +static struct device_driver platram_driver = { + .name = "mtd-ram", + .bus = &platform_bus_type, + .probe = platram_probe, + .remove = platram_remove, +}; + +/* module init/exit */ + +static int __init platram_init(void) +{ + printk("Generic platform RAM MTD, (c) 2004 Simtec Electronics\n"); + return driver_register(&platram_driver); +} + +static void __exit platram_exit(void) +{ + driver_unregister(&platram_driver); +} + +module_init(platram_init); +module_exit(platram_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Ben Dooks "); +MODULE_DESCRIPTION("MTD platform RAM map driver"); diff --git a/include/linux/mtd/plat-ram.h b/include/linux/mtd/plat-ram.h new file mode 100644 index 000000000000..2332eda07e0e --- /dev/null +++ b/include/linux/mtd/plat-ram.h @@ -0,0 +1,35 @@ +/* linux/include/mtd/plat-ram.h + * + * (c) 2004 Simtec Electronics + * http://www.simtec.co.uk/products/SWLINUX/ + * Ben Dooks + * + * Generic platform device based RAM map + * + * $Id: plat-ram.h,v 1.2 2005/01/24 00:37:40 bjd Exp $ + * + * 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 __LINUX_MTD_PLATRAM_H +#define __LINUX_MTD_PLATRAM_H __FILE__ + +#define PLATRAM_RO (0) +#define PLATRAM_RW (1) + +struct platdata_mtd_ram { + char *mapname; + char **probes; + struct mtd_partition *partitions; + int nr_partitions; + int bankwidth; + + /* control callbacks */ + + void (*set_rw)(struct device *dev, int to); +}; + +#endif /* __LINUX_MTD_PLATRAM_H */ -- 2.20.1