diff options
Diffstat (limited to 'drivers/macintosh/macio-adb.c')
| -rw-r--r-- | drivers/macintosh/macio-adb.c | 211 |
1 files changed, 211 insertions, 0 deletions
diff --git a/drivers/macintosh/macio-adb.c b/drivers/macintosh/macio-adb.c new file mode 100644 index 000000000..65048b0da --- /dev/null +++ b/drivers/macintosh/macio-adb.c @@ -0,0 +1,211 @@ +/* + * 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/sched.h> +#include <asm/prom.h> +#include <asm/adb.h> +#include <asm/io.h> +#include <asm/hydra.h> +#include <asm/irq.h> +#include <asm/system.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 *adb; +static struct adb_request *current_req, *last_req; +static unsigned char adb_rbuf[16]; + +static void macio_adb_interrupt(int irq, void *arg, struct pt_regs *regs); +static int macio_adb_send_request(struct adb_request *req, int sync); +static int macio_adb_autopoll(int on); +static void macio_adb_poll(void); +static void completed(void); + +void macio_adb_init(void) +{ + struct device_node *adbs; + + adbs = find_compatible_devices("adb", "chrp,adb0"); + if (adbs == 0) + return; + +#if 1 + { int i; + + printk("macio_adb_init: node = %p, addrs =", adbs->node); + for (i = 0; i < adbs->n_addrs; ++i) + printk(" %x(%x)", adbs->addrs[i].address, adbs->addrs[i].size); + printk(", intrs ="); + for (i = 0; i < adbs->n_intrs; ++i) + printk(" %x", adbs->intrs[i]); + printk("\n"); } +#endif + + adb = (volatile struct adb_regs *) adbs->addrs->address; + + if (request_irq(openpic_to_irq(adbs->intrs[0]), macio_adb_interrupt, + 0, "ADB", (void *)0)) { + printk(KERN_ERR "ADB: can't get irq %d\n", + openpic_to_irq(adbs->intrs[0])); + return; + } + + 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); + out_8(&adb->intr_enb.r, DFB | TAG); + + adb_hardware = ADB_MACIO; + adb_send_request = macio_adb_send_request; + adb_autopoll = macio_adb_autopoll; +} + +static int macio_adb_autopoll(int on) +{ + out_8(&adb->autopoll.r, on? APE: 0); + return 0; +} + + +/* Send an ADB command */ +static int macio_adb_send_request(struct adb_request *req, int sync) +{ + unsigned long mflags; + + req->next = 0; + req->sent = 0; + req->complete = 0; + req->reply_len = 0; + + save_flags(mflags); + cli(); + 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); + } + restore_flags(mflags); + + if (sync) { + while (!req->complete) + macio_adb_poll(); + } + + return 0; +} + +static void macio_adb_interrupt(int irq, void *arg, struct pt_regs *regs) +{ + int i, n, err; + struct adb_request *req; + + if (in_8(&adb->intr.r) & TAG) { + 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); + completed(); + } + } + out_8(&adb->intr.r, 0); + } + + if (in_8(&adb->intr.r) & DFB) { + 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); + } + completed(); + } else if (err == 0) { + /* autopoll data */ + n = in_8(&adb->dcount.r) & HMB; + for (i = 0; i < n; ++i) + adb_rbuf[i] = in_8(&adb->data[i].r); + adb_input(adb_rbuf, n, regs, + in_8(&adb->dcount.r) & APD); + } + out_8(&adb->error.r, 0); + out_8(&adb->intr.r, 0); + } +} + +static void completed(void) +{ + struct adb_request *req = current_req; + + req->complete = 1; + current_req = req->next; + if (current_req) + out_8(&adb->ctrl.r, in_8(&adb->ctrl.r) | TAR); + if (req->done) + (*req->done)(req); +} + +static void macio_adb_poll(void) +{ + unsigned long flags; + + save_flags(flags); + cli(); + if (in_8(&adb->intr.r) != 0) + macio_adb_interrupt(0, 0, 0); + restore_flags(flags); +} |