linux/drivers/pcmcia/omap_cf.c

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/*
* omap_cf.c -- OMAP 16xx CompactFlash controller driver
*
* Copyright (c) 2005 David Brownell
*
* 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.
*/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/interrupt.h>
#include <pcmcia/ss.h>
#include <asm/hardware.h>
#include <asm/io.h>
#include <asm/sizes.h>
#include <asm/arch/mux.h>
#include <asm/arch/tc.h>
/* NOTE: don't expect this to support many I/O cards. The 16xx chips have
* hard-wired timings to support Compact Flash memory cards; they won't work
* with various other devices (like WLAN adapters) without some external
* logic to help out.
*
* NOTE: CF controller docs disagree with address space docs as to where
* CF_BASE really lives; this is a doc erratum.
*/
#define CF_BASE 0xfffe2800
/* status; read after IRQ */
#define CF_STATUS_REG __REG16(CF_BASE + 0x00)
# define CF_STATUS_BAD_READ (1 << 2)
# define CF_STATUS_BAD_WRITE (1 << 1)
# define CF_STATUS_CARD_DETECT (1 << 0)
/* which chipselect (CS0..CS3) is used for CF (active low) */
#define CF_CFG_REG __REG16(CF_BASE + 0x02)
/* card reset */
#define CF_CONTROL_REG __REG16(CF_BASE + 0x04)
# define CF_CONTROL_RESET (1 << 0)
#define omap_cf_present() (!(CF_STATUS_REG & CF_STATUS_CARD_DETECT))
/*--------------------------------------------------------------------------*/
static const char driver_name[] = "omap_cf";
struct omap_cf_socket {
struct pcmcia_socket socket;
struct timer_list timer;
unsigned present:1;
unsigned active:1;
struct platform_device *pdev;
unsigned long phys_cf;
u_int irq;
struct resource iomem;
};
#define POLL_INTERVAL (2 * HZ)
#define SZ_2K (2 * SZ_1K)
/*--------------------------------------------------------------------------*/
static int omap_cf_ss_init(struct pcmcia_socket *s)
{
return 0;
}
/* the timer is primarily to kick this socket's pccardd */
static void omap_cf_timer(unsigned long _cf)
{
struct omap_cf_socket *cf = (void *) _cf;
unsigned present = omap_cf_present();
if (present != cf->present) {
cf->present = present;
pr_debug("%s: card %s\n", driver_name,
present ? "present" : "gone");
pcmcia_parse_events(&cf->socket, SS_DETECT);
}
if (cf->active)
mod_timer(&cf->timer, jiffies + POLL_INTERVAL);
}
/* This irq handler prevents "irqNNN: nobody cared" messages as drivers
* claim the card's IRQ. It may also detect some card insertions, but
* not removals; it can't always eliminate timer irqs.
*/
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:55:46 +02:00
static irqreturn_t omap_cf_irq(int irq, void *_cf)
{
omap_cf_timer((unsigned long)_cf);
return IRQ_HANDLED;
}
static int omap_cf_get_status(struct pcmcia_socket *s, u_int *sp)
{
if (!sp)
return -EINVAL;
/* NOTE CF is always 3VCARD */
if (omap_cf_present()) {
struct omap_cf_socket *cf;
*sp = SS_READY | SS_DETECT | SS_POWERON | SS_3VCARD;
cf = container_of(s, struct omap_cf_socket, socket);
s->irq.AssignedIRQ = 0;
s->pci_irq = cf->irq;
} else
*sp = 0;
return 0;
}
static int
omap_cf_set_socket(struct pcmcia_socket *sock, struct socket_state_t *s)
{
u16 control;
/* REVISIT some non-OSK boards may support power switching */
switch (s->Vcc) {
case 0:
case 33:
break;
default:
return -EINVAL;
}
control = CF_CONTROL_REG;
if (s->flags & SS_RESET)
CF_CONTROL_REG = CF_CONTROL_RESET;
else
CF_CONTROL_REG = 0;
pr_debug("%s: Vcc %d, io_irq %d, flags %04x csc %04x\n",
driver_name, s->Vcc, s->io_irq, s->flags, s->csc_mask);
return 0;
}
static int omap_cf_ss_suspend(struct pcmcia_socket *s)
{
pr_debug("%s: %s\n", driver_name, __FUNCTION__);
return omap_cf_set_socket(s, &dead_socket);
}
/* regions are 2K each: mem, attrib, io (and reserved-for-ide) */
static int
omap_cf_set_io_map(struct pcmcia_socket *s, struct pccard_io_map *io)
{
struct omap_cf_socket *cf;
cf = container_of(s, struct omap_cf_socket, socket);
io->flags &= MAP_ACTIVE|MAP_ATTRIB|MAP_16BIT;
io->start = cf->phys_cf + SZ_4K;
io->stop = io->start + SZ_2K - 1;
return 0;
}
static int
omap_cf_set_mem_map(struct pcmcia_socket *s, struct pccard_mem_map *map)
{
struct omap_cf_socket *cf;
if (map->card_start)
return -EINVAL;
cf = container_of(s, struct omap_cf_socket, socket);
map->static_start = cf->phys_cf;
map->flags &= MAP_ACTIVE|MAP_ATTRIB|MAP_16BIT;
if (map->flags & MAP_ATTRIB)
map->static_start += SZ_2K;
return 0;
}
static struct pccard_operations omap_cf_ops = {
.init = omap_cf_ss_init,
.suspend = omap_cf_ss_suspend,
.get_status = omap_cf_get_status,
.set_socket = omap_cf_set_socket,
.set_io_map = omap_cf_set_io_map,
.set_mem_map = omap_cf_set_mem_map,
};
/*--------------------------------------------------------------------------*/
/*
* NOTE: right now the only board-specific platform_data is
* "what chipselect is used". Boards could want more.
*/
static int __init omap_cf_probe(struct platform_device *pdev)
{
unsigned seg;
struct omap_cf_socket *cf;
int irq;
int status;
seg = (int) pdev->dev.platform_data;
if (seg == 0 || seg > 3)
return -ENODEV;
/* either CFLASH.IREQ (INT_1610_CF) or some GPIO */
irq = platform_get_irq(pdev, 0);
if (irq < 0)
return -EINVAL;
cf = kzalloc(sizeof *cf, GFP_KERNEL);
if (!cf)
return -ENOMEM;
init_timer(&cf->timer);
cf->timer.function = omap_cf_timer;
cf->timer.data = (unsigned long) cf;
cf->pdev = pdev;
platform_set_drvdata(pdev, cf);
/* this primarily just shuts up irq handling noise */
status = request_irq(irq, omap_cf_irq, IRQF_SHARED,
driver_name, cf);
if (status < 0)
goto fail0;
cf->irq = irq;
cf->socket.pci_irq = irq;
switch (seg) {
/* NOTE: CS0 could be configured too ... */
case 1:
cf->phys_cf = OMAP_CS1_PHYS;
break;
case 2:
cf->phys_cf = OMAP_CS2_PHYS;
break;
case 3:
cf->phys_cf = omap_cs3_phys();
break;
default:
goto fail1;
}
cf->iomem.start = cf->phys_cf;
cf->iomem.end = cf->iomem.end + SZ_8K - 1;
cf->iomem.flags = IORESOURCE_MEM;
/* pcmcia layer only remaps "real" memory */
cf->socket.io_offset = (unsigned long)
ioremap(cf->phys_cf + SZ_4K, SZ_2K);
if (!cf->socket.io_offset)
goto fail1;
if (!request_mem_region(cf->phys_cf, SZ_8K, driver_name))
goto fail1;
/* NOTE: CF conflicts with MMC1 */
omap_cfg_reg(W11_1610_CF_CD1);
omap_cfg_reg(P11_1610_CF_CD2);
omap_cfg_reg(R11_1610_CF_IOIS16);
omap_cfg_reg(V10_1610_CF_IREQ);
omap_cfg_reg(W10_1610_CF_RESET);
CF_CFG_REG = ~(1 << seg);
pr_info("%s: cs%d on irq %d\n", driver_name, seg, irq);
/* NOTE: better EMIFS setup might support more cards; but the
* TRM only shows how to affect regular flash signals, not their
* CF/PCMCIA variants...
*/
pr_debug("%s: cs%d, previous ccs %08x acs %08x\n", driver_name,
seg, EMIFS_CCS(seg), EMIFS_ACS(seg));
EMIFS_CCS(seg) = 0x0004a1b3; /* synch mode 4 etc */
EMIFS_ACS(seg) = 0x00000000; /* OE hold/setup */
/* CF uses armxor_ck, which is "always" available */
pr_debug("%s: sts %04x cfg %04x control %04x %s\n", driver_name,
CF_STATUS_REG, CF_CFG_REG, CF_CONTROL_REG,
omap_cf_present() ? "present" : "(not present)");
cf->socket.owner = THIS_MODULE;
cf->socket.dev.parent = &pdev->dev;
cf->socket.ops = &omap_cf_ops;
cf->socket.resource_ops = &pccard_static_ops;
cf->socket.features = SS_CAP_PCCARD | SS_CAP_STATIC_MAP
| SS_CAP_MEM_ALIGN;
cf->socket.map_size = SZ_2K;
cf->socket.io[0].res = &cf->iomem;
status = pcmcia_register_socket(&cf->socket);
if (status < 0)
goto fail2;
cf->active = 1;
mod_timer(&cf->timer, jiffies + POLL_INTERVAL);
return 0;
fail2:
release_mem_region(cf->phys_cf, SZ_8K);
fail1:
if (cf->socket.io_offset)
iounmap((void __iomem *) cf->socket.io_offset);
free_irq(irq, cf);
fail0:
kfree(cf);
return status;
}
static int __exit omap_cf_remove(struct platform_device *pdev)
{
struct omap_cf_socket *cf = platform_get_drvdata(pdev);
cf->active = 0;
pcmcia_unregister_socket(&cf->socket);
del_timer_sync(&cf->timer);
iounmap((void __iomem *) cf->socket.io_offset);
release_mem_region(cf->phys_cf, SZ_8K);
free_irq(cf->irq, cf);
kfree(cf);
return 0;
}
static int omap_cf_suspend(struct platform_device *pdev, pm_message_t mesg)
{
return pcmcia_socket_dev_suspend(&pdev->dev, mesg);
}
static int omap_cf_resume(struct platform_device *pdev)
{
return pcmcia_socket_dev_resume(&pdev->dev);
}
static struct platform_driver omap_cf_driver = {
.driver = {
.name = (char *) driver_name,
},
.remove = __exit_p(omap_cf_remove),
.suspend = omap_cf_suspend,
.resume = omap_cf_resume,
};
static int __init omap_cf_init(void)
{
if (cpu_is_omap16xx())
return platform_driver_probe(&omap_cf_driver, omap_cf_probe);
return -ENODEV;
}
static void __exit omap_cf_exit(void)
{
if (cpu_is_omap16xx())
platform_driver_unregister(&omap_cf_driver);
}
module_init(omap_cf_init);
module_exit(omap_cf_exit);
MODULE_DESCRIPTION("OMAP CF Driver");
MODULE_LICENSE("GPL");