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authorLinus Torvalds <torvalds@woody.osdl.org>2006-12-06 08:10:55 -0800
committerLinus Torvalds <torvalds@woody.osdl.org>2006-12-06 08:10:55 -0800
commitdd6a7c19e4630f635467246a81b8e0cc818c05e6 (patch)
tree8fc93cdef4070183cbd3fa06019c84728380b389 /arch/sh/drivers
parentdd8856bda5f1308beb113281b248683992998a9e (diff)
parentea0f8feaa041f3ccec3d6b8ee51325b177daef06 (diff)
downloadlwn-dd6a7c19e4630f635467246a81b8e0cc818c05e6.tar.gz
lwn-dd6a7c19e4630f635467246a81b8e0cc818c05e6.zip
Merge master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6
* master.kernel.org:/pub/scm/linux/kernel/git/lethal/sh-2.6: (43 commits) sh: sh775x/titan fixes for irq header changes. sh: update r7780rp defconfig. sh: compile fixes for header cleanup. sh: Fixup pte_mkhuge() build failure. sh: set KBUILD_IMAGE to something sensible. sh: show held locks in stack trace with lockdep. sh: platform_pata support for R7780RP sh: stacktrace/lockdep/irqflags tracing support. sh: Fixup movli.l/movco.l atomic ops for gcc4. sh: dyntick infrastructure. sh: Clock framework tidying. sh: Turn off IRQs around get_timer_offset() calls. sh: Get the PGD right in oops case with 64-bit PTEs. sh: Fix store queue bitmap end. sh: More flexible + SH7780 earlyprintk SCIF support. sh: Fixup various PAGE_SIZE == 4096 assumptions. sh: Fixup 4K irq stacks. sh: dma-api channel capability extensions. sh: Drop name overload in dma-sh. sh: Make dma-isa depend on ISA_DMA_API. ...
Diffstat (limited to 'arch/sh/drivers')
-rw-r--r--arch/sh/drivers/Kconfig9
-rw-r--r--arch/sh/drivers/Makefile2
-rw-r--r--arch/sh/drivers/dma/Makefile4
-rw-r--r--arch/sh/drivers/dma/dma-api.c274
-rw-r--r--arch/sh/drivers/dma/dma-sh.c9
-rw-r--r--arch/sh/drivers/dma/dma-sysfs.c23
-rw-r--r--arch/sh/drivers/pci/ops-titan.c24
-rw-r--r--arch/sh/drivers/pci/pci-sh7780.c14
-rw-r--r--arch/sh/drivers/push-switch.c138
9 files changed, 379 insertions, 118 deletions
diff --git a/arch/sh/drivers/Kconfig b/arch/sh/drivers/Kconfig
new file mode 100644
index 000000000000..c54c758e6243
--- /dev/null
+++ b/arch/sh/drivers/Kconfig
@@ -0,0 +1,9 @@
+menu "Additional SuperH Device Drivers"
+
+config PUSH_SWITCH
+ tristate "Push switch support"
+ help
+ This enables support for the push switch framework, a simple
+ framework that allows for sysfs driven switch status reporting.
+
+endmenu
diff --git a/arch/sh/drivers/Makefile b/arch/sh/drivers/Makefile
index 338c3729d270..bf18dbfb6787 100644
--- a/arch/sh/drivers/Makefile
+++ b/arch/sh/drivers/Makefile
@@ -5,4 +5,4 @@
obj-$(CONFIG_PCI) += pci/
obj-$(CONFIG_SH_DMA) += dma/
obj-$(CONFIG_SUPERHYWAY) += superhyway/
-
+obj-$(CONFIG_PUSH_SWITCH) += push-switch.o
diff --git a/arch/sh/drivers/dma/Makefile b/arch/sh/drivers/dma/Makefile
index 065d4c90970e..db1295d32268 100644
--- a/arch/sh/drivers/dma/Makefile
+++ b/arch/sh/drivers/dma/Makefile
@@ -2,8 +2,8 @@
# Makefile for the SuperH DMA specific kernel interface routines under Linux.
#
-obj-y += dma-api.o dma-isa.o
+obj-y += dma-api.o
+obj-$(CONFIG_ISA_DMA_API) += dma-isa.o
obj-$(CONFIG_SYSFS) += dma-sysfs.o
obj-$(CONFIG_SH_DMA) += dma-sh.o
obj-$(CONFIG_SH_DREAMCAST) += dma-pvr2.o dma-g2.o
-
diff --git a/arch/sh/drivers/dma/dma-api.c b/arch/sh/drivers/dma/dma-api.c
index 47c3e837599b..e062067edd24 100644
--- a/arch/sh/drivers/dma/dma-api.c
+++ b/arch/sh/drivers/dma/dma-api.c
@@ -11,61 +11,27 @@
*/
#include <linux/init.h>
#include <linux/module.h>
-#include <linux/interrupt.h>
#include <linux/spinlock.h>
#include <linux/proc_fs.h>
#include <linux/list.h>
#include <linux/platform_device.h>
+#include <linux/mm.h>
#include <asm/dma.h>
DEFINE_SPINLOCK(dma_spin_lock);
static LIST_HEAD(registered_dmac_list);
-/*
- * A brief note about the reasons for this API as it stands.
- *
- * For starters, the old ISA DMA API didn't work for us for a number of
- * reasons, for one, the vast majority of channels on the SH DMAC are
- * dual-address mode only, and both the new and the old DMA APIs are after the
- * concept of managing a DMA buffer, which doesn't overly fit this model very
- * well. In addition to which, the new API is largely geared at IOMMUs and
- * GARTs, and doesn't even support the channel notion very well.
- *
- * The other thing that's a marginal issue, is the sheer number of random DMA
- * engines that are present (ie, in boards like the Dreamcast), some of which
- * cascade off of the SH DMAC, and others do not. As such, there was a real
- * need for a scalable subsystem that could deal with both single and
- * dual-address mode usage, in addition to interoperating with cascaded DMACs.
- *
- * There really isn't any reason why this needs to be SH specific, though I'm
- * not aware of too many other processors (with the exception of some MIPS)
- * that have the same concept of a dual address mode, or any real desire to
- * actually make use of the DMAC even if such a subsystem were exposed
- * elsewhere.
- *
- * The idea for this was derived from the ARM port, which acted as an excellent
- * reference when trying to address these issues.
- *
- * It should also be noted that the decision to add Yet Another DMA API(tm) to
- * the kernel wasn't made easily, and was only decided upon after conferring
- * with jejb with regards to the state of the old and new APIs as they applied
- * to these circumstances. Philip Blundell was also a great help in figuring
- * out some single-address mode DMA semantics that were otherwise rather
- * confusing.
- */
-
struct dma_info *get_dma_info(unsigned int chan)
{
struct dma_info *info;
- unsigned int total = 0;
/*
* Look for each DMAC's range to determine who the owner of
* the channel is.
*/
list_for_each_entry(info, &registered_dmac_list, list) {
- total += info->nr_channels;
- if (chan > total)
+ if ((chan < info->first_channel_nr) ||
+ (chan >= info->first_channel_nr + info->nr_channels))
continue;
return info;
@@ -73,6 +39,22 @@ struct dma_info *get_dma_info(unsigned int chan)
return NULL;
}
+EXPORT_SYMBOL(get_dma_info);
+
+struct dma_info *get_dma_info_by_name(const char *dmac_name)
+{
+ struct dma_info *info;
+
+ list_for_each_entry(info, &registered_dmac_list, list) {
+ if (dmac_name && (strcmp(dmac_name, info->name) != 0))
+ continue;
+ else
+ return info;
+ }
+
+ return NULL;
+}
+EXPORT_SYMBOL(get_dma_info_by_name);
static unsigned int get_nr_channels(void)
{
@@ -91,63 +73,161 @@ static unsigned int get_nr_channels(void)
struct dma_channel *get_dma_channel(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
+ struct dma_channel *channel;
+ int i;
- if (!info)
+ if (unlikely(!info))
return ERR_PTR(-EINVAL);
- return info->channels + chan;
+ for (i = 0; i < info->nr_channels; i++) {
+ channel = &info->channels[i];
+ if (channel->chan == chan)
+ return channel;
+ }
+
+ return NULL;
}
+EXPORT_SYMBOL(get_dma_channel);
int get_dma_residue(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
- struct dma_channel *channel = &info->channels[chan];
+ struct dma_channel *channel = get_dma_channel(chan);
if (info->ops->get_residue)
return info->ops->get_residue(channel);
return 0;
}
+EXPORT_SYMBOL(get_dma_residue);
-int request_dma(unsigned int chan, const char *dev_id)
+static int search_cap(const char **haystack, const char *needle)
{
- struct dma_info *info = get_dma_info(chan);
- struct dma_channel *channel = &info->channels[chan];
+ const char **p;
+
+ for (p = haystack; *p; p++)
+ if (strcmp(*p, needle) == 0)
+ return 1;
+
+ return 0;
+}
+
+/**
+ * request_dma_bycap - Allocate a DMA channel based on its capabilities
+ * @dmac: List of DMA controllers to search
+ * @caps: List of capabilites
+ *
+ * Search all channels of all DMA controllers to find a channel which
+ * matches the requested capabilities. The result is the channel
+ * number if a match is found, or %-ENODEV if no match is found.
+ *
+ * Note that not all DMA controllers export capabilities, in which
+ * case they can never be allocated using this API, and so
+ * request_dma() must be used specifying the channel number.
+ */
+int request_dma_bycap(const char **dmac, const char **caps, const char *dev_id)
+{
+ unsigned int found = 0;
+ struct dma_info *info;
+ const char **p;
+ int i;
+
+ BUG_ON(!dmac || !caps);
+
+ list_for_each_entry(info, &registered_dmac_list, list)
+ if (strcmp(*dmac, info->name) == 0) {
+ found = 1;
+ break;
+ }
+
+ if (!found)
+ return -ENODEV;
+
+ for (i = 0; i < info->nr_channels; i++) {
+ struct dma_channel *channel = &info->channels[i];
+
+ if (unlikely(!channel->caps))
+ continue;
+
+ for (p = caps; *p; p++) {
+ if (!search_cap(channel->caps, *p))
+ break;
+ if (request_dma(channel->chan, dev_id) == 0)
+ return channel->chan;
+ }
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL(request_dma_bycap);
+
+int dmac_search_free_channel(const char *dev_id)
+{
+ struct dma_channel *channel = { 0 };
+ struct dma_info *info = get_dma_info(0);
+ int i;
+
+ for (i = 0; i < info->nr_channels; i++) {
+ channel = &info->channels[i];
+ if (unlikely(!channel))
+ return -ENODEV;
+
+ if (atomic_read(&channel->busy) == 0)
+ break;
+ }
- down(&channel->sem);
+ if (info->ops->request) {
+ int result = info->ops->request(channel);
+ if (result)
+ return result;
- if (!info->ops || chan >= MAX_DMA_CHANNELS) {
- up(&channel->sem);
- return -EINVAL;
+ atomic_set(&channel->busy, 1);
+ return channel->chan;
}
- atomic_set(&channel->busy, 1);
+ return -ENOSYS;
+}
+
+int request_dma(unsigned int chan, const char *dev_id)
+{
+ struct dma_channel *channel = { 0 };
+ struct dma_info *info = get_dma_info(chan);
+ int result;
+
+ channel = get_dma_channel(chan);
+ if (atomic_xchg(&channel->busy, 1))
+ return -EBUSY;
strlcpy(channel->dev_id, dev_id, sizeof(channel->dev_id));
- up(&channel->sem);
+ if (info->ops->request) {
+ result = info->ops->request(channel);
+ if (result)
+ atomic_set(&channel->busy, 0);
- if (info->ops->request)
- return info->ops->request(channel);
+ return result;
+ }
return 0;
}
+EXPORT_SYMBOL(request_dma);
void free_dma(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
- struct dma_channel *channel = &info->channels[chan];
+ struct dma_channel *channel = get_dma_channel(chan);
if (info->ops->free)
info->ops->free(channel);
atomic_set(&channel->busy, 0);
}
+EXPORT_SYMBOL(free_dma);
void dma_wait_for_completion(unsigned int chan)
{
struct dma_info *info = get_dma_info(chan);
- struct dma_channel *channel = &info->channels[chan];
+ struct dma_channel *channel = get_dma_channel(chan);
if (channel->flags & DMA_TEI_CAPABLE) {
wait_event(channel->wait_queue,
@@ -158,21 +238,52 @@ void dma_wait_for_completion(unsigned int chan)
while (info->ops->get_residue(channel))
cpu_relax();
}
+EXPORT_SYMBOL(dma_wait_for_completion);
+
+int register_chan_caps(const char *dmac, struct dma_chan_caps *caps)
+{
+ struct dma_info *info;
+ unsigned int found = 0;
+ int i;
+
+ list_for_each_entry(info, &registered_dmac_list, list)
+ if (strcmp(dmac, info->name) == 0) {
+ found = 1;
+ break;
+ }
+
+ if (unlikely(!found))
+ return -ENODEV;
+
+ for (i = 0; i < info->nr_channels; i++, caps++) {
+ struct dma_channel *channel;
+
+ if ((info->first_channel_nr + i) != caps->ch_num)
+ return -EINVAL;
+
+ channel = &info->channels[i];
+ channel->caps = caps->caplist;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(register_chan_caps);
void dma_configure_channel(unsigned int chan, unsigned long flags)
{
struct dma_info *info = get_dma_info(chan);
- struct dma_channel *channel = &info->channels[chan];
+ struct dma_channel *channel = get_dma_channel(chan);
if (info->ops->configure)
info->ops->configure(channel, flags);
}
+EXPORT_SYMBOL(dma_configure_channel);
int dma_xfer(unsigned int chan, unsigned long from,
unsigned long to, size_t size, unsigned int mode)
{
struct dma_info *info = get_dma_info(chan);
- struct dma_channel *channel = &info->channels[chan];
+ struct dma_channel *channel = get_dma_channel(chan);
channel->sar = from;
channel->dar = to;
@@ -181,8 +292,20 @@ int dma_xfer(unsigned int chan, unsigned long from,
return info->ops->xfer(channel);
}
+EXPORT_SYMBOL(dma_xfer);
+
+int dma_extend(unsigned int chan, unsigned long op, void *param)
+{
+ struct dma_info *info = get_dma_info(chan);
+ struct dma_channel *channel = get_dma_channel(chan);
+
+ if (info->ops->extend)
+ return info->ops->extend(channel, op, param);
+
+ return -ENOSYS;
+}
+EXPORT_SYMBOL(dma_extend);
-#ifdef CONFIG_PROC_FS
static int dma_read_proc(char *buf, char **start, off_t off,
int len, int *eof, void *data)
{
@@ -214,8 +337,6 @@ static int dma_read_proc(char *buf, char **start, off_t off,
return p - buf;
}
-#endif
-
int register_dmac(struct dma_info *info)
{
@@ -224,8 +345,7 @@ int register_dmac(struct dma_info *info)
INIT_LIST_HEAD(&info->list);
printk(KERN_INFO "DMA: Registering %s handler (%d channel%s).\n",
- info->name, info->nr_channels,
- info->nr_channels > 1 ? "s" : "");
+ info->name, info->nr_channels, info->nr_channels > 1 ? "s" : "");
BUG_ON((info->flags & DMAC_CHANNELS_CONFIGURED) && !info->channels);
@@ -242,28 +362,26 @@ int register_dmac(struct dma_info *info)
size = sizeof(struct dma_channel) * info->nr_channels;
- info->channels = kmalloc(size, GFP_KERNEL);
+ info->channels = kzalloc(size, GFP_KERNEL);
if (!info->channels)
return -ENOMEM;
-
- memset(info->channels, 0, size);
}
total_channels = get_nr_channels();
for (i = 0; i < info->nr_channels; i++) {
- struct dma_channel *chan = info->channels + i;
+ struct dma_channel *chan = &info->channels[i];
+
+ atomic_set(&chan->busy, 0);
- chan->chan = i;
- chan->vchan = i + total_channels;
+ chan->chan = info->first_channel_nr + i;
+ chan->vchan = info->first_channel_nr + i + total_channels;
memcpy(chan->dev_id, "Unused", 7);
if (info->flags & DMAC_CHANNELS_TEI_CAPABLE)
chan->flags |= DMA_TEI_CAPABLE;
- init_MUTEX(&chan->sem);
init_waitqueue_head(&chan->wait_queue);
-
dma_create_sysfs_files(chan, info);
}
@@ -271,6 +389,7 @@ int register_dmac(struct dma_info *info)
return 0;
}
+EXPORT_SYMBOL(register_dmac);
void unregister_dmac(struct dma_info *info)
{
@@ -285,31 +404,16 @@ void unregister_dmac(struct dma_info *info)
list_del(&info->list);
platform_device_unregister(info->pdev);
}
+EXPORT_SYMBOL(unregister_dmac);
static int __init dma_api_init(void)
{
- printk("DMA: Registering DMA API.\n");
-
-#ifdef CONFIG_PROC_FS
+ printk(KERN_NOTICE "DMA: Registering DMA API.\n");
create_proc_read_entry("dma", 0, 0, dma_read_proc, 0);
-#endif
-
return 0;
}
-
subsys_initcall(dma_api_init);
MODULE_AUTHOR("Paul Mundt <lethal@linux-sh.org>");
MODULE_DESCRIPTION("DMA API for SuperH");
MODULE_LICENSE("GPL");
-
-EXPORT_SYMBOL(request_dma);
-EXPORT_SYMBOL(free_dma);
-EXPORT_SYMBOL(register_dmac);
-EXPORT_SYMBOL(get_dma_residue);
-EXPORT_SYMBOL(get_dma_info);
-EXPORT_SYMBOL(get_dma_channel);
-EXPORT_SYMBOL(dma_xfer);
-EXPORT_SYMBOL(dma_wait_for_completion);
-EXPORT_SYMBOL(dma_configure_channel);
-
diff --git a/arch/sh/drivers/dma/dma-sh.c b/arch/sh/drivers/dma/dma-sh.c
index 660786013350..f63721ed86c2 100644
--- a/arch/sh/drivers/dma/dma-sh.c
+++ b/arch/sh/drivers/dma/dma-sh.c
@@ -94,20 +94,13 @@ static int sh_dmac_request_dma(struct dma_channel *chan)
if (unlikely(!chan->flags & DMA_TEI_CAPABLE))
return 0;
- chan->name = kzalloc(32, GFP_KERNEL);
- if (unlikely(chan->name == NULL))
- return -ENOMEM;
- snprintf(chan->name, 32, "DMAC Transfer End (Channel %d)",
- chan->chan);
-
return request_irq(get_dmte_irq(chan->chan), dma_tei,
- IRQF_DISABLED, chan->name, chan);
+ IRQF_DISABLED, chan->dev_id, chan);
}
static void sh_dmac_free_dma(struct dma_channel *chan)
{
free_irq(get_dmte_irq(chan->chan), chan);
- kfree(chan->name);
}
static void
diff --git a/arch/sh/drivers/dma/dma-sysfs.c b/arch/sh/drivers/dma/dma-sysfs.c
index 29b8ef9873d1..eebcd4768bbf 100644
--- a/arch/sh/drivers/dma/dma-sysfs.c
+++ b/arch/sh/drivers/dma/dma-sysfs.c
@@ -3,7 +3,7 @@
*
* sysfs interface for SH DMA API
*
- * Copyright (C) 2004, 2005 Paul Mundt
+ * Copyright (C) 2004 - 2006 Paul Mundt
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
@@ -21,7 +21,6 @@
static struct sysdev_class dma_sysclass = {
set_kset_name("dma"),
};
-
EXPORT_SYMBOL(dma_sysclass);
static ssize_t dma_show_devices(struct sys_device *dev, char *buf)
@@ -31,7 +30,10 @@ static ssize_t dma_show_devices(struct sys_device *dev, char *buf)
for (i = 0; i < MAX_DMA_CHANNELS; i++) {
struct dma_info *info = get_dma_info(i);
- struct dma_channel *channel = &info->channels[i];
+ struct dma_channel *channel = get_dma_channel(i);
+
+ if (unlikely(!info) || !channel)
+ continue;
len += sprintf(buf + len, "%2d: %14s %s\n",
channel->chan, info->name,
@@ -125,11 +127,16 @@ int dma_create_sysfs_files(struct dma_channel *chan, struct dma_info *info)
if (ret)
return ret;
- sysdev_create_file(dev, &attr_dev_id);
- sysdev_create_file(dev, &attr_count);
- sysdev_create_file(dev, &attr_mode);
- sysdev_create_file(dev, &attr_flags);
- sysdev_create_file(dev, &attr_config);
+ ret |= sysdev_create_file(dev, &attr_dev_id);
+ ret |= sysdev_create_file(dev, &attr_count);
+ ret |= sysdev_create_file(dev, &attr_mode);
+ ret |= sysdev_create_file(dev, &attr_flags);
+ ret |= sysdev_create_file(dev, &attr_config);
+
+ if (unlikely(ret)) {
+ dev_err(&info->pdev->dev, "Failed creating attrs\n");
+ return ret;
+ }
snprintf(name, sizeof(name), "dma%d", chan->chan);
return sysfs_create_link(&info->pdev->dev.kobj, &dev->kobj, name);
diff --git a/arch/sh/drivers/pci/ops-titan.c b/arch/sh/drivers/pci/ops-titan.c
index cd56d53375e7..ac8ee2312cd8 100644
--- a/arch/sh/drivers/pci/ops-titan.c
+++ b/arch/sh/drivers/pci/ops-titan.c
@@ -15,25 +15,21 @@
#include <linux/types.h>
#include <linux/init.h>
#include <linux/pci.h>
-#include <asm/io.h>
+#include <linux/io.h>
#include <asm/titan.h>
#include "pci-sh4.h"
+static char titan_irq_tab[] __initdata = {
+ TITAN_IRQ_WAN,
+ TITAN_IRQ_LAN,
+ TITAN_IRQ_MPCIA,
+ TITAN_IRQ_MPCIB,
+ TITAN_IRQ_USB,
+};
+
int __init pcibios_map_platform_irq(struct pci_dev *pdev, u8 slot, u8 pin)
{
- int irq = -1;
-
- switch (slot) {
- case 0: irq = TITAN_IRQ_WAN; break; /* eth0 (WAN) */
- case 1: irq = TITAN_IRQ_LAN; break; /* eth1 (LAN) */
- case 2: irq = TITAN_IRQ_MPCIA; break; /* mPCI A */
- case 3: irq = TITAN_IRQ_MPCIB; break; /* mPCI B */
- case 4: irq = TITAN_IRQ_USB; break; /* USB */
- default:
- printk(KERN_INFO "PCI: Bad IRQ mapping "
- "request for slot %d\n", slot);
- return -1;
- }
+ int irq = titan_irq_tab[slot];
printk("PCI: Mapping TITAN IRQ for slot %d, pin %c to irq %d\n",
slot, pin - 1 + 'A', irq);
diff --git a/arch/sh/drivers/pci/pci-sh7780.c b/arch/sh/drivers/pci/pci-sh7780.c
index d6e635296534..602b644c35ad 100644
--- a/arch/sh/drivers/pci/pci-sh7780.c
+++ b/arch/sh/drivers/pci/pci-sh7780.c
@@ -22,6 +22,20 @@
#include <linux/delay.h>
#include "pci-sh4.h"
+#define INTC_BASE 0xffd00000
+#define INTC_ICR0 (INTC_BASE+0x0)
+#define INTC_ICR1 (INTC_BASE+0x1c)
+#define INTC_INTPRI (INTC_BASE+0x10)
+#define INTC_INTREQ (INTC_BASE+0x24)
+#define INTC_INTMSK0 (INTC_BASE+0x44)
+#define INTC_INTMSK1 (INTC_BASE+0x48)
+#define INTC_INTMSK2 (INTC_BASE+0x40080)
+#define INTC_INTMSKCLR0 (INTC_BASE+0x64)
+#define INTC_INTMSKCLR1 (INTC_BASE+0x68)
+#define INTC_INTMSKCLR2 (INTC_BASE+0x40084)
+#define INTC_INT2MSKR (INTC_BASE+0x40038)
+#define INTC_INT2MSKCR (INTC_BASE+0x4003c)
+
/*
* Initialization. Try all known PCI access methods. Note that we support
* using both PCI BIOS and direct access: in such cases, we use I/O ports
diff --git a/arch/sh/drivers/push-switch.c b/arch/sh/drivers/push-switch.c
new file mode 100644
index 000000000000..f2b9157c314f
--- /dev/null
+++ b/arch/sh/drivers/push-switch.c
@@ -0,0 +1,138 @@
+/*
+ * Generic push-switch framework
+ *
+ * Copyright (C) 2006 Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <asm/push-switch.h>
+
+#define DRV_NAME "push-switch"
+#define DRV_VERSION "0.1.0"
+
+static ssize_t switch_show(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct push_switch_platform_info *psw_info = dev->platform_data;
+ return sprintf(buf, "%s\n", psw_info->name);
+}
+static DEVICE_ATTR(switch, S_IRUGO, switch_show, NULL);
+
+static void switch_timer(unsigned long data)
+{
+ struct push_switch *psw = (struct push_switch *)data;
+
+ schedule_work(&psw->work);
+}
+
+static void switch_work_handler(void *data)
+{
+ struct platform_device *pdev = data;
+ struct push_switch *psw = platform_get_drvdata(pdev);
+
+ psw->state = 0;
+
+ kobject_uevent(&pdev->dev.kobj, KOBJ_CHANGE);
+}
+
+static int switch_drv_probe(struct platform_device *pdev)
+{
+ struct push_switch_platform_info *psw_info;
+ struct push_switch *psw;
+ int ret, irq;
+
+ psw = kzalloc(sizeof(struct push_switch), GFP_KERNEL);
+ if (unlikely(!psw))
+ return -ENOMEM;
+
+ irq = platform_get_irq(pdev, 0);
+ if (unlikely(irq < 0)) {
+ ret = -ENODEV;
+ goto err;
+ }
+
+ psw_info = pdev->dev.platform_data;
+ BUG_ON(!psw_info);
+
+ ret = request_irq(irq, psw_info->irq_handler,
+ IRQF_DISABLED | psw_info->irq_flags,
+ psw_info->name ? psw_info->name : DRV_NAME, pdev);
+ if (unlikely(ret < 0))
+ goto err;
+
+ if (psw_info->name) {
+ ret = device_create_file(&pdev->dev, &dev_attr_switch);
+ if (unlikely(ret)) {
+ dev_err(&pdev->dev, "Failed creating device attrs\n");
+ ret = -EINVAL;
+ goto err_irq;
+ }
+ }
+
+ INIT_WORK(&psw->work, switch_work_handler, pdev);
+ init_timer(&psw->debounce);
+
+ psw->debounce.function = switch_timer;
+ psw->debounce.data = (unsigned long)psw;
+
+ platform_set_drvdata(pdev, psw);
+
+ return 0;
+
+err_irq:
+ free_irq(irq, pdev);
+err:
+ kfree(psw);
+ return ret;
+}
+
+static int switch_drv_remove(struct platform_device *pdev)
+{
+ struct push_switch *psw = platform_get_drvdata(pdev);
+ struct push_switch_platform_info *psw_info = pdev->dev.platform_data;
+ int irq = platform_get_irq(pdev, 0);
+
+ if (psw_info->name)
+ device_remove_file(&pdev->dev, &dev_attr_switch);
+
+ platform_set_drvdata(pdev, NULL);
+ flush_scheduled_work();
+ del_timer_sync(&psw->debounce);
+ free_irq(irq, pdev);
+
+ kfree(psw);
+
+ return 0;
+}
+
+static struct platform_driver switch_driver = {
+ .probe = switch_drv_probe,
+ .remove = switch_drv_remove,
+ .driver = {
+ .name = DRV_NAME,
+ },
+};
+
+static int __init switch_init(void)
+{
+ printk(KERN_NOTICE DRV_NAME ": version %s loaded\n", DRV_VERSION);
+ return platform_driver_register(&switch_driver);
+}
+
+static void __exit switch_exit(void)
+{
+ platform_driver_unregister(&switch_driver);
+}
+module_init(switch_init);
+module_exit(switch_exit);
+
+MODULE_VERSION(DRV_VERSION);
+MODULE_AUTHOR("Paul Mundt");
+MODULE_LICENSE("GPLv2");