linux/drivers/pcmcia/pxa2xx_sharpsl.c
David Brownell 49a4ec188f fix hotplug for legacy platform drivers
We've had various reports of some legacy "probe the hardware" style
platform drivers having nasty problems with hotplug support.

The core issue is that those legacy drivers don't fully conform to the
driver model.  They assume a role that should be the responsibility of
infrastructure code: creating device nodes.

The "modprobe" step in hotplugging relies on drivers to have split those
roles into different modules.  The lack of this split causes the problems.
When a driver creates nodes for devices that don't exist (sending a hotplug
event), then exits (aborting one modprobe) before the "modprobe $MODALIAS"
step completes (by failing, since it's in the middle of a modprobe), the
result can be an endless loop of modprobe invocations ...  badness.

This fix uses the newish per-device flag controlling issuance of "add"
events.  (A previous version of this patch used a per-device "driver can
hotplug" flag, which only scrubbed $MODALIAS from the environment rather
than suppressing the entire hotplug event.) It also shrinks that flag to
one bit, saving a word in "struct device".

So the net of this patch is removing some nasty failures with legacy
drivers, while retaining hotplug capability for the majority of platform
drivers.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Cc: Greg KH <gregkh@suse.de>
Cc: Andres Salomon <dilinger@debian.org>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08 11:15:10 -07:00

287 lines
7.5 KiB
C

/*
* Sharp SL-C7xx Series PCMCIA routines
*
* Copyright (c) 2004-2005 Richard Purdie
*
* Based on Sharp's 2.4 kernel patches and pxa2xx_mainstone.c
*
* 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.
*
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <asm/mach-types.h>
#include <asm/hardware.h>
#include <asm/irq.h>
#include <asm/hardware/scoop.h>
#include "soc_common.h"
#define NO_KEEP_VS 0x0001
#define SCOOP_DEV platform_scoop_config->devs
static void sharpsl_pcmcia_init_reset(struct soc_pcmcia_socket *skt)
{
struct scoop_pcmcia_dev *scoopdev = &SCOOP_DEV[skt->nr];
reset_scoop(scoopdev->dev);
/* Shared power controls need to be handled carefully */
if (platform_scoop_config->power_ctrl)
platform_scoop_config->power_ctrl(scoopdev->dev, 0x0000, skt->nr);
else
write_scoop_reg(scoopdev->dev, SCOOP_CPR, 0x0000);
scoopdev->keep_vs = NO_KEEP_VS;
scoopdev->keep_rd = 0;
}
static int sharpsl_pcmcia_hw_init(struct soc_pcmcia_socket *skt)
{
int ret;
if (platform_scoop_config->pcmcia_init)
platform_scoop_config->pcmcia_init();
/* Register interrupts */
if (SCOOP_DEV[skt->nr].cd_irq >= 0) {
struct pcmcia_irqs cd_irq;
cd_irq.sock = skt->nr;
cd_irq.irq = SCOOP_DEV[skt->nr].cd_irq;
cd_irq.str = SCOOP_DEV[skt->nr].cd_irq_str;
ret = soc_pcmcia_request_irqs(skt, &cd_irq, 1);
if (ret) {
printk(KERN_ERR "Request for Compact Flash IRQ failed\n");
return ret;
}
}
skt->irq = SCOOP_DEV[skt->nr].irq;
return 0;
}
static void sharpsl_pcmcia_hw_shutdown(struct soc_pcmcia_socket *skt)
{
if (SCOOP_DEV[skt->nr].cd_irq >= 0) {
struct pcmcia_irqs cd_irq;
cd_irq.sock = skt->nr;
cd_irq.irq = SCOOP_DEV[skt->nr].cd_irq;
cd_irq.str = SCOOP_DEV[skt->nr].cd_irq_str;
soc_pcmcia_free_irqs(skt, &cd_irq, 1);
}
}
static void sharpsl_pcmcia_socket_state(struct soc_pcmcia_socket *skt,
struct pcmcia_state *state)
{
unsigned short cpr, csr;
struct device *scoop = SCOOP_DEV[skt->nr].dev;
cpr = read_scoop_reg(SCOOP_DEV[skt->nr].dev, SCOOP_CPR);
write_scoop_reg(scoop, SCOOP_IRM, 0x00FF);
write_scoop_reg(scoop, SCOOP_ISR, 0x0000);
write_scoop_reg(scoop, SCOOP_IRM, 0x0000);
csr = read_scoop_reg(scoop, SCOOP_CSR);
if (csr & 0x0004) {
/* card eject */
write_scoop_reg(scoop, SCOOP_CDR, 0x0000);
SCOOP_DEV[skt->nr].keep_vs = NO_KEEP_VS;
}
else if (!(SCOOP_DEV[skt->nr].keep_vs & NO_KEEP_VS)) {
/* keep vs1,vs2 */
write_scoop_reg(scoop, SCOOP_CDR, 0x0000);
csr |= SCOOP_DEV[skt->nr].keep_vs;
}
else if (cpr & 0x0003) {
/* power on */
write_scoop_reg(scoop, SCOOP_CDR, 0x0000);
SCOOP_DEV[skt->nr].keep_vs = (csr & 0x00C0);
}
else {
/* card detect */
if ((machine_is_spitz() || machine_is_borzoi()) && skt->nr == 1) {
write_scoop_reg(scoop, SCOOP_CDR, 0x0000);
} else {
write_scoop_reg(scoop, SCOOP_CDR, 0x0002);
}
}
state->detect = (csr & 0x0004) ? 0 : 1;
state->ready = (csr & 0x0002) ? 1 : 0;
state->bvd1 = (csr & 0x0010) ? 1 : 0;
state->bvd2 = (csr & 0x0020) ? 1 : 0;
state->wrprot = (csr & 0x0008) ? 1 : 0;
state->vs_3v = (csr & 0x0040) ? 0 : 1;
state->vs_Xv = (csr & 0x0080) ? 0 : 1;
if ((cpr & 0x0080) && ((cpr & 0x8040) != 0x8040)) {
printk(KERN_ERR "sharpsl_pcmcia_socket_state(): CPR=%04X, Low voltage!\n", cpr);
}
}
static int sharpsl_pcmcia_configure_socket(struct soc_pcmcia_socket *skt,
const socket_state_t *state)
{
unsigned long flags;
struct device *scoop = SCOOP_DEV[skt->nr].dev;
unsigned short cpr, ncpr, ccr, nccr, mcr, nmcr, imr, nimr;
switch (state->Vcc) {
case 0: break;
case 33: break;
case 50: break;
default:
printk(KERN_ERR "sharpsl_pcmcia_configure_socket(): bad Vcc %u\n", state->Vcc);
return -1;
}
if ((state->Vpp!=state->Vcc) && (state->Vpp!=0)) {
printk(KERN_ERR "CF slot cannot support Vpp %u\n", state->Vpp);
return -1;
}
local_irq_save(flags);
nmcr = (mcr = read_scoop_reg(scoop, SCOOP_MCR)) & ~0x0010;
ncpr = (cpr = read_scoop_reg(scoop, SCOOP_CPR)) & ~0x0083;
nccr = (ccr = read_scoop_reg(scoop, SCOOP_CCR)) & ~0x0080;
nimr = (imr = read_scoop_reg(scoop, SCOOP_IMR)) & ~0x003E;
if ((machine_is_spitz() || machine_is_borzoi() || machine_is_akita()) && skt->nr == 0) {
ncpr |= (state->Vcc == 33) ? 0x0002 :
(state->Vcc == 50) ? 0x0002 : 0;
} else {
ncpr |= (state->Vcc == 33) ? 0x0001 :
(state->Vcc == 50) ? 0x0002 : 0;
}
nmcr |= (state->flags&SS_IOCARD) ? 0x0010 : 0;
ncpr |= (state->flags&SS_OUTPUT_ENA) ? 0x0080 : 0;
nccr |= (state->flags&SS_RESET)? 0x0080: 0;
nimr |= ((skt->status&SS_DETECT) ? 0x0004 : 0)|
((skt->status&SS_READY) ? 0x0002 : 0)|
((skt->status&SS_BATDEAD)? 0x0010 : 0)|
((skt->status&SS_BATWARN)? 0x0020 : 0)|
((skt->status&SS_STSCHG) ? 0x0010 : 0)|
((skt->status&SS_WRPROT) ? 0x0008 : 0);
if (!(ncpr & 0x0003)) {
SCOOP_DEV[skt->nr].keep_rd = 0;
} else if (!SCOOP_DEV[skt->nr].keep_rd) {
if (nccr & 0x0080)
SCOOP_DEV[skt->nr].keep_rd = 1;
else
nccr |= 0x0080;
}
if (mcr != nmcr)
write_scoop_reg(scoop, SCOOP_MCR, nmcr);
if (cpr != ncpr) {
if (platform_scoop_config->power_ctrl)
platform_scoop_config->power_ctrl(scoop, ncpr , skt->nr);
else
write_scoop_reg(scoop, SCOOP_CPR, ncpr);
}
if (ccr != nccr)
write_scoop_reg(scoop, SCOOP_CCR, nccr);
if (imr != nimr)
write_scoop_reg(scoop, SCOOP_IMR, nimr);
local_irq_restore(flags);
return 0;
}
static void sharpsl_pcmcia_socket_init(struct soc_pcmcia_socket *skt)
{
sharpsl_pcmcia_init_reset(skt);
/* Enable interrupt */
write_scoop_reg(SCOOP_DEV[skt->nr].dev, SCOOP_IMR, 0x00C0);
write_scoop_reg(SCOOP_DEV[skt->nr].dev, SCOOP_MCR, 0x0101);
SCOOP_DEV[skt->nr].keep_vs = NO_KEEP_VS;
}
static void sharpsl_pcmcia_socket_suspend(struct soc_pcmcia_socket *skt)
{
sharpsl_pcmcia_init_reset(skt);
}
static struct pcmcia_low_level sharpsl_pcmcia_ops = {
.owner = THIS_MODULE,
.hw_init = sharpsl_pcmcia_hw_init,
.hw_shutdown = sharpsl_pcmcia_hw_shutdown,
.socket_state = sharpsl_pcmcia_socket_state,
.configure_socket = sharpsl_pcmcia_configure_socket,
.socket_init = sharpsl_pcmcia_socket_init,
.socket_suspend = sharpsl_pcmcia_socket_suspend,
.first = 0,
.nr = 0,
};
#ifdef CONFIG_SA1100_COLLIE
#include "sa11xx_base.h"
int __init pcmcia_collie_init(struct device *dev)
{
int ret = -ENODEV;
if (machine_is_collie())
ret = sa11xx_drv_pcmcia_probe(dev, &sharpsl_pcmcia_ops, 0, 1);
return ret;
}
#else
static struct platform_device *sharpsl_pcmcia_device;
static int __init sharpsl_pcmcia_init(void)
{
int ret;
sharpsl_pcmcia_ops.nr = platform_scoop_config->num_devs;
sharpsl_pcmcia_device = platform_device_alloc("pxa2xx-pcmcia", -1);
if (!sharpsl_pcmcia_device)
return -ENOMEM;
sharpsl_pcmcia_device->dev.uevent_suppress = 0;
sharpsl_pcmcia_device->dev.platform_data = &sharpsl_pcmcia_ops;
sharpsl_pcmcia_device->dev.parent = platform_scoop_config->devs[0].dev;
ret = platform_device_add(sharpsl_pcmcia_device);
if (ret)
platform_device_put(sharpsl_pcmcia_device);
return ret;
}
static void __exit sharpsl_pcmcia_exit(void)
{
platform_device_unregister(sharpsl_pcmcia_device);
}
fs_initcall(sharpsl_pcmcia_init);
module_exit(sharpsl_pcmcia_exit);
#endif
MODULE_DESCRIPTION("Sharp SL Series PCMCIA Support");
MODULE_LICENSE("GPL");