[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 <ben@simtec.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/mtd/maps/Kconfig b/drivers/mtd/maps/Kconfig
index 8480057..7d21d43 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 @@
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 7ffe02b..d2e6dcc 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-$(CONFIG_MTD_WRSBC8260) += wr_sbc82xx_flash.o
obj-$(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 0000000..808f943
--- /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 <ben@simtec.co.uk>
+ *
+ * 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 <linux/module.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/ioport.h>
+#include <linux/device.h>
+
+#include <linux/mtd/mtd.h>
+#include <linux/mtd/map.h>
+#include <linux/mtd/partitions.h>
+#include <linux/mtd/plat-ram.h>
+
+#include <asm/io.h>
+
+/* 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 <ben@simtec.co.uk>");
+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 0000000..2332eda
--- /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 <ben@simtec.co.uk>
+ *
+ * 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 */