285 lines
6.4 KiB
C
285 lines
6.4 KiB
C
/*
|
|
* Driver for the ADB controller in the Mac I/O (Hydra) chip.
|
|
*/
|
|
#include <stdarg.h>
|
|
#include <linux/types.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/interrupt.h>
|
|
#include <asm/prom.h>
|
|
#include <linux/adb.h>
|
|
#include <asm/io.h>
|
|
#include <asm/pgtable.h>
|
|
#include <asm/hydra.h>
|
|
#include <asm/irq.h>
|
|
#include <asm/system.h>
|
|
#include <linux/init.h>
|
|
#include <linux/ioport.h>
|
|
|
|
struct preg {
|
|
unsigned char r;
|
|
char pad[15];
|
|
};
|
|
|
|
struct adb_regs {
|
|
struct preg intr;
|
|
struct preg data[9];
|
|
struct preg intr_enb;
|
|
struct preg dcount;
|
|
struct preg error;
|
|
struct preg ctrl;
|
|
struct preg autopoll;
|
|
struct preg active_hi;
|
|
struct preg active_lo;
|
|
struct preg test;
|
|
};
|
|
|
|
/* Bits in intr and intr_enb registers */
|
|
#define DFB 1 /* data from bus */
|
|
#define TAG 2 /* transfer access grant */
|
|
|
|
/* Bits in dcount register */
|
|
#define HMB 0x0f /* how many bytes */
|
|
#define APD 0x10 /* auto-poll data */
|
|
|
|
/* Bits in error register */
|
|
#define NRE 1 /* no response error */
|
|
#define DLE 2 /* data lost error */
|
|
|
|
/* Bits in ctrl register */
|
|
#define TAR 1 /* transfer access request */
|
|
#define DTB 2 /* data to bus */
|
|
#define CRE 4 /* command response expected */
|
|
#define ADB_RST 8 /* ADB reset */
|
|
|
|
/* Bits in autopoll register */
|
|
#define APE 1 /* autopoll enable */
|
|
|
|
static volatile struct adb_regs __iomem *adb;
|
|
static struct adb_request *current_req, *last_req;
|
|
static DEFINE_SPINLOCK(macio_lock);
|
|
|
|
static int macio_probe(void);
|
|
static int macio_init(void);
|
|
static irqreturn_t macio_adb_interrupt(int irq, void *arg);
|
|
static int macio_send_request(struct adb_request *req, int sync);
|
|
static int macio_adb_autopoll(int devs);
|
|
static void macio_adb_poll(void);
|
|
static int macio_adb_reset_bus(void);
|
|
|
|
struct adb_driver macio_adb_driver = {
|
|
"MACIO",
|
|
macio_probe,
|
|
macio_init,
|
|
macio_send_request,
|
|
/*macio_write,*/
|
|
macio_adb_autopoll,
|
|
macio_adb_poll,
|
|
macio_adb_reset_bus
|
|
};
|
|
|
|
int macio_probe(void)
|
|
{
|
|
struct device_node *np;
|
|
|
|
np = of_find_compatible_node(NULL, "adb", "chrp,adb0");
|
|
if (np) {
|
|
of_node_put(np);
|
|
return 0;
|
|
}
|
|
return -ENODEV;
|
|
}
|
|
|
|
int macio_init(void)
|
|
{
|
|
struct device_node *adbs;
|
|
struct resource r;
|
|
unsigned int irq;
|
|
|
|
adbs = of_find_compatible_node(NULL, "adb", "chrp,adb0");
|
|
if (adbs == 0)
|
|
return -ENXIO;
|
|
|
|
if (of_address_to_resource(adbs, 0, &r)) {
|
|
of_node_put(adbs);
|
|
return -ENXIO;
|
|
}
|
|
adb = ioremap(r.start, sizeof(struct adb_regs));
|
|
|
|
out_8(&adb->ctrl.r, 0);
|
|
out_8(&adb->intr.r, 0);
|
|
out_8(&adb->error.r, 0);
|
|
out_8(&adb->active_hi.r, 0xff); /* for now, set all devices active */
|
|
out_8(&adb->active_lo.r, 0xff);
|
|
out_8(&adb->autopoll.r, APE);
|
|
|
|
irq = irq_of_parse_and_map(adbs, 0);
|
|
of_node_put(adbs);
|
|
if (request_irq(irq, macio_adb_interrupt, 0, "ADB", (void *)0)) {
|
|
printk(KERN_ERR "ADB: can't get irq %d\n", irq);
|
|
return -EAGAIN;
|
|
}
|
|
out_8(&adb->intr_enb.r, DFB | TAG);
|
|
|
|
printk("adb: mac-io driver 1.0 for unified ADB\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int macio_adb_autopoll(int devs)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&macio_lock, flags);
|
|
out_8(&adb->active_hi.r, devs >> 8);
|
|
out_8(&adb->active_lo.r, devs);
|
|
out_8(&adb->autopoll.r, devs? APE: 0);
|
|
spin_unlock_irqrestore(&macio_lock, flags);
|
|
return 0;
|
|
}
|
|
|
|
static int macio_adb_reset_bus(void)
|
|
{
|
|
unsigned long flags;
|
|
int timeout = 1000000;
|
|
|
|
/* Hrm... we may want to not lock interrupts for so
|
|
* long ... oh well, who uses that chip anyway ? :)
|
|
* That function will be seldomly used during boot
|
|
* on rare machines, so...
|
|
*/
|
|
spin_lock_irqsave(&macio_lock, flags);
|
|
out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | ADB_RST);
|
|
while ((in_8(&adb->ctrl.r) & ADB_RST) != 0) {
|
|
if (--timeout == 0) {
|
|
out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) & ~ADB_RST);
|
|
return -1;
|
|
}
|
|
}
|
|
spin_unlock_irqrestore(&macio_lock, flags);
|
|
return 0;
|
|
}
|
|
|
|
/* Send an ADB command */
|
|
static int macio_send_request(struct adb_request *req, int sync)
|
|
{
|
|
unsigned long flags;
|
|
int i;
|
|
|
|
if (req->data[0] != ADB_PACKET)
|
|
return -EINVAL;
|
|
|
|
for (i = 0; i < req->nbytes - 1; ++i)
|
|
req->data[i] = req->data[i+1];
|
|
--req->nbytes;
|
|
|
|
req->next = NULL;
|
|
req->sent = 0;
|
|
req->complete = 0;
|
|
req->reply_len = 0;
|
|
|
|
spin_lock_irqsave(&macio_lock, flags);
|
|
if (current_req != 0) {
|
|
last_req->next = req;
|
|
last_req = req;
|
|
} else {
|
|
current_req = last_req = req;
|
|
out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
|
|
}
|
|
spin_unlock_irqrestore(&macio_lock, flags);
|
|
|
|
if (sync) {
|
|
while (!req->complete)
|
|
macio_adb_poll();
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static irqreturn_t macio_adb_interrupt(int irq, void *arg)
|
|
{
|
|
int i, n, err;
|
|
struct adb_request *req = NULL;
|
|
unsigned char ibuf[16];
|
|
int ibuf_len = 0;
|
|
int complete = 0;
|
|
int autopoll = 0;
|
|
int handled = 0;
|
|
|
|
spin_lock(&macio_lock);
|
|
if (in_8(&adb->intr.r) & TAG) {
|
|
handled = 1;
|
|
if ((req = current_req) != 0) {
|
|
/* put the current request in */
|
|
for (i = 0; i < req->nbytes; ++i)
|
|
out_8(&adb->data[i].r, req->data[i]);
|
|
out_8(&adb->dcount.r, req->nbytes & HMB);
|
|
req->sent = 1;
|
|
if (req->reply_expected) {
|
|
out_8(&adb->ctrl.r, DTB + CRE);
|
|
} else {
|
|
out_8(&adb->ctrl.r, DTB);
|
|
current_req = req->next;
|
|
complete = 1;
|
|
if (current_req)
|
|
out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
|
|
}
|
|
}
|
|
out_8(&adb->intr.r, 0);
|
|
}
|
|
|
|
if (in_8(&adb->intr.r) & DFB) {
|
|
handled = 1;
|
|
err = in_8(&adb->error.r);
|
|
if (current_req && current_req->sent) {
|
|
/* this is the response to a command */
|
|
req = current_req;
|
|
if (err == 0) {
|
|
req->reply_len = in_8(&adb->dcount.r) & HMB;
|
|
for (i = 0; i < req->reply_len; ++i)
|
|
req->reply[i] = in_8(&adb->data[i].r);
|
|
}
|
|
current_req = req->next;
|
|
complete = 1;
|
|
if (current_req)
|
|
out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR);
|
|
} else if (err == 0) {
|
|
/* autopoll data */
|
|
n = in_8(&adb->dcount.r) & HMB;
|
|
for (i = 0; i < n; ++i)
|
|
ibuf[i] = in_8(&adb->data[i].r);
|
|
ibuf_len = n;
|
|
autopoll = (in_8(&adb->dcount.r) & APD) != 0;
|
|
}
|
|
out_8(&adb->error.r, 0);
|
|
out_8(&adb->intr.r, 0);
|
|
}
|
|
spin_unlock(&macio_lock);
|
|
if (complete && req) {
|
|
void (*done)(struct adb_request *) = req->done;
|
|
mb();
|
|
req->complete = 1;
|
|
/* Here, we assume that if the request has a done member, the
|
|
* struct request will survive to setting req->complete to 1
|
|
*/
|
|
if (done)
|
|
(*done)(req);
|
|
}
|
|
if (ibuf_len)
|
|
adb_input(ibuf, ibuf_len, autopoll);
|
|
|
|
return IRQ_RETVAL(handled);
|
|
}
|
|
|
|
static void macio_adb_poll(void)
|
|
{
|
|
unsigned long flags;
|
|
|
|
local_irq_save(flags);
|
|
if (in_8(&adb->intr.r) != 0)
|
|
macio_adb_interrupt(0, NULL);
|
|
local_irq_restore(flags);
|
|
}
|