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Release 4.7 drivers/macintosh/via-cuda.c

/*
 * Device driver for the via-cuda on Apple Powermacs.
 *
 * The VIA (versatile interface adapter) interfaces to the CUDA,
 * a 6805 microprocessor core which controls the ADB (Apple Desktop
 * Bus) which connects to the keyboard and mouse.  The CUDA also
 * controls system power and the RTC (real time clock) chip.
 *
 * Copyright (C) 1996 Paul Mackerras.
 */
#include <stdarg.h>
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/adb.h>
#include <linux/cuda.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#ifdef CONFIG_PPC
#include <asm/prom.h>
#include <asm/machdep.h>
#else
#include <asm/macintosh.h>
#include <asm/macints.h>
#include <asm/mac_via.h>
#endif
#include <asm/io.h>
#include <linux/init.h>


static volatile unsigned char __iomem *via;
static DEFINE_SPINLOCK(cuda_lock);

/* VIA registers - spaced 0x200 bytes apart */

#define RS		0x200		
/* skip between registers */

#define B		0		
/* B-side data */

#define A		RS		
/* A-side data */

#define DIRB		(2*RS)		
/* B-side direction (1=output) */

#define DIRA		(3*RS)		
/* A-side direction (1=output) */

#define T1CL		(4*RS)		
/* Timer 1 ctr/latch (low 8 bits) */

#define T1CH		(5*RS)		
/* Timer 1 counter (high 8 bits) */

#define T1LL		(6*RS)		
/* Timer 1 latch (low 8 bits) */

#define T1LH		(7*RS)		
/* Timer 1 latch (high 8 bits) */

#define T2CL		(8*RS)		
/* Timer 2 ctr/latch (low 8 bits) */

#define T2CH		(9*RS)		
/* Timer 2 counter (high 8 bits) */

#define SR		(10*RS)		
/* Shift register */

#define ACR		(11*RS)		
/* Auxiliary control register */

#define PCR		(12*RS)		
/* Peripheral control register */

#define IFR		(13*RS)		
/* Interrupt flag register */

#define IER		(14*RS)		
/* Interrupt enable register */

#define ANH		(15*RS)		
/* A-side data, no handshake */

/* Bits in B data register: all active low */

#define TREQ		0x08		
/* Transfer request (input) */

#define TACK		0x10		
/* Transfer acknowledge (output) */

#define TIP		0x20		
/* Transfer in progress (output) */

/* Bits in ACR */

#define SR_CTRL		0x1c		
/* Shift register control bits */

#define SR_EXT		0x0c		
/* Shift on external clock */

#define SR_OUT		0x10		
/* Shift out if 1 */

/* Bits in IFR and IER */

#define IER_SET		0x80		
/* set bits in IER */

#define IER_CLR		0		
/* clear bits in IER */

#define SR_INT		0x04		
/* Shift register full/empty */


static enum cuda_state {
    
idle,
    
sent_first_byte,
    
sending,
    
reading,
    
read_done,
    
awaiting_reply
} 
cuda_state;


static struct adb_request *current_req;

static struct adb_request *last_req;

static unsigned char cuda_rbuf[16];

static unsigned char *reply_ptr;

static int reading_reply;

static int data_index;

static int cuda_irq;
#ifdef CONFIG_PPC

static struct device_node *vias;
#endif

static int cuda_fully_inited;

#ifdef CONFIG_ADB
static int cuda_probe(void);
static int cuda_send_request(struct adb_request *req, int sync);
static int cuda_adb_autopoll(int devs);
static int cuda_reset_adb_bus(void);
#endif /* CONFIG_ADB */

static int cuda_init_via(void);
static void cuda_start(void);
static irqreturn_t cuda_interrupt(int irq, void *arg);
static void cuda_input(unsigned char *buf, int nb);
void cuda_poll(void);
static int cuda_write(struct adb_request *req);

int cuda_request(struct adb_request *req,
		 void (*done)(struct adb_request *), int nbytes, ...);

#ifdef CONFIG_ADB

struct adb_driver via_cuda_driver = {
	.name         = "CUDA",
	.probe        = cuda_probe,
	.send_request = cuda_send_request,
	.autopoll     = cuda_adb_autopoll,
	.poll         = cuda_poll,
	.reset_bus    = cuda_reset_adb_bus,
};
#endif /* CONFIG_ADB */

#ifdef CONFIG_MAC

int __init find_via_cuda(void) { struct adb_request req; int err; if (macintosh_config->adb_type != MAC_ADB_CUDA) return 0; via = via1; cuda_state = idle; err = cuda_init_via(); if (err) { printk(KERN_ERR "cuda_init_via() failed\n"); via = NULL; return 0; } /* enable autopoll */ cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1); while (!req.complete) cuda_poll(); return 1; }

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finn thainfinn thain7787.50%120.00%
pre-gitpre-git1011.36%360.00%
paul mackerraspaul mackerras11.14%120.00%
Total88100.00%5100.00%

#else
int __init find_via_cuda(void) { struct adb_request req; phys_addr_t taddr; const u32 *reg; int err; if (vias != 0) return 1; vias = of_find_node_by_name(NULL, "via-cuda"); if (vias == 0) return 0; reg = of_get_property(vias, "reg", NULL); if (reg == NULL) { printk(KERN_ERR "via-cuda: No \"reg\" property !\n"); goto fail; } taddr = of_translate_address(vias, reg); if (taddr == 0) { printk(KERN_ERR "via-cuda: Can't translate address !\n"); goto fail; } via = ioremap(taddr, 0x2000); if (via == NULL) { printk(KERN_ERR "via-cuda: Can't map address !\n"); goto fail; } cuda_state = idle; sys_ctrler = SYS_CTRLER_CUDA; err = cuda_init_via(); if (err) { printk(KERN_ERR "cuda_init_via() failed\n"); via = NULL; return 0; } /* Clear and enable interrupts, but only on PPC. On 68K it's done */ /* for us by the main VIA driver in arch/m68k/mac/via.c */ out_8(&via[IFR], 0x7f); /* clear interrupts by writing 1s */ out_8(&via[IER], IER_SET|SR_INT); /* enable interrupt from SR */ /* enable autopoll */ cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, 1); while (!req.complete) cuda_poll(); return 1; fail: of_node_put(vias); vias = NULL; return 0; }

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benjamin herrenschmidtbenjamin herrenschmidt8034.19%18.33%
finn thainfinn thain114.70%18.33%
paul mackerraspaul mackerras104.27%18.33%
linus torvaldslinus torvalds10.43%18.33%
stephen rothwellstephen rothwell10.43%18.33%
jeremy kerrjeremy kerr10.43%18.33%
Total234100.00%12100.00%

#endif /* !defined CONFIG_MAC */
static int __init via_cuda_start(void) { if (via == NULL) return -ENODEV; #ifdef CONFIG_MAC cuda_irq = IRQ_MAC_ADB; #else cuda_irq = irq_of_parse_and_map(vias, 0); if (cuda_irq == NO_IRQ) { printk(KERN_ERR "via-cuda: can't map interrupts for %s\n", vias->full_name); return -ENODEV; } #endif if (request_irq(cuda_irq, cuda_interrupt, 0, "ADB", cuda_interrupt)) { printk(KERN_ERR "via-cuda: can't request irq %d\n", cuda_irq); return -EAGAIN; } printk("Macintosh CUDA driver v0.5 for Unified ADB.\n"); cuda_fully_inited = 1; return 0; }

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pre-gitpre-git5553.92%666.67%
benjamin herrenschmidtbenjamin herrenschmidt4039.22%111.11%
finn thainfinn thain54.90%111.11%
paul mackerraspaul mackerras21.96%111.11%
Total102100.00%9100.00%

device_initcall(via_cuda_start); #ifdef CONFIG_ADB
static int cuda_probe(void) { #ifdef CONFIG_PPC if (sys_ctrler != SYS_CTRLER_CUDA) return -ENODEV; #else if (macintosh_config->adb_type != MAC_ADB_CUDA) return -ENODEV; #endif if (via == NULL) return -ENODEV; return 0; }

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pre-gitpre-git4488.00%133.33%
geert uytterhoevengeert uytterhoeven36.00%133.33%
paul mackerraspaul mackerras36.00%133.33%
Total50100.00%3100.00%

#endif /* CONFIG_ADB */ #define WAIT_FOR(cond, what) \ do { \ int x; \ for (x = 1000; !(cond); --x) { \ if (x == 0) { \ printk("Timeout waiting for " what "\n"); \ return -ENXIO; \ } \ udelay(100); \ } \ } while (0)
static int __init cuda_init_via(void) { out_8(&via[DIRB], (in_8(&via[DIRB]) | TACK | TIP) & ~TREQ); /* TACK & TIP out */ out_8(&via[B], in_8(&via[B]) | TACK | TIP); /* negate them */ out_8(&via[ACR] ,(in_8(&via[ACR]) & ~SR_CTRL) | SR_EXT); /* SR data in */ (void)in_8(&via[SR]); /* clear any left-over data */ #ifdef CONFIG_PPC out_8(&via[IER], 0x7f); /* disable interrupts from VIA */ (void)in_8(&via[IER]); #else out_8(&via[IER], SR_INT); /* disable SR interrupt from VIA */ #endif /* delay 4ms and then clear any pending interrupt */ mdelay(4); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); /* sync with the CUDA - assert TACK without TIP */ out_8(&via[B], in_8(&via[B]) & ~TACK); /* wait for the CUDA to assert TREQ in response */ WAIT_FOR((in_8(&via[B]) & TREQ) == 0, "CUDA response to sync"); /* wait for the interrupt and then clear it */ WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (2)"); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); /* finish the sync by negating TACK */ out_8(&via[B], in_8(&via[B]) | TACK); /* wait for the CUDA to negate TREQ and the corresponding interrupt */ WAIT_FOR(in_8(&via[B]) & TREQ, "CUDA response to sync (3)"); WAIT_FOR(in_8(&via[IFR]) & SR_INT, "CUDA response to sync (4)"); (void)in_8(&via[SR]); out_8(&via[IFR], SR_INT); out_8(&via[B], in_8(&via[B]) | TIP); /* should be unnecessary */ return 0; }

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pre-gitpre-git16947.61%342.86%
paul mackerraspaul mackerras16546.48%228.57%
finn thainfinn thain205.63%114.29%
geert uytterhoevengeert uytterhoeven10.28%114.29%
Total355100.00%7100.00%

#ifdef CONFIG_ADB /* Send an ADB command */
static int cuda_send_request(struct adb_request *req, int sync) { int i; if ((via == NULL) || !cuda_fully_inited) { req->complete = 1; return -ENXIO; } req->reply_expected = 1; i = cuda_write(req); if (i) return i; if (sync) { while (!req->complete) cuda_poll(); } return 0; }

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/* Enable/disable autopolling */
static int cuda_adb_autopoll(int devs) { struct adb_request req; if ((via == NULL) || !cuda_fully_inited) return -ENXIO; cuda_request(&req, NULL, 3, CUDA_PACKET, CUDA_AUTOPOLL, (devs? 1: 0)); while (!req.complete) cuda_poll(); return 0; }

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/* Reset adb bus - how do we do this?? */
static int cuda_reset_adb_bus(void) { struct adb_request req; if ((via == NULL) || !cuda_fully_inited) return -ENXIO; cuda_request(&req, NULL, 2, ADB_PACKET, 0); /* maybe? */ while (!req.complete) cuda_poll(); return 0; }

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#endif /* CONFIG_ADB */ /* Construct and send a cuda request */
int cuda_request(struct adb_request *req, void (*done)(struct adb_request *), int nbytes, ...) { va_list list; int i; if (via == NULL) { req->complete = 1; return -ENXIO; } req->nbytes = nbytes; req->done = done; va_start(list, nbytes); for (i = 0; i < nbytes; ++i) req->data[i] = va_arg(list, int); va_end(list); req->reply_expected = 1; return cuda_write(req); }

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EXPORT_SYMBOL(cuda_request);
static int cuda_write(struct adb_request *req) { unsigned long flags; if (req->nbytes < 2 || req->data[0] > CUDA_PACKET) { req->complete = 1; return -EINVAL; } req->next = NULL; req->sent = 0; req->complete = 0; req->reply_len = 0; spin_lock_irqsave(&cuda_lock, flags); if (current_req != 0) { last_req->next = req; last_req = req; } else { current_req = req; last_req = req; if (cuda_state == idle) cuda_start(); } spin_unlock_irqrestore(&cuda_lock, flags); return 0; }

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pre-gitpre-git11692.80%571.43%
paul mackerraspaul mackerras86.40%114.29%
al viroal viro10.80%114.29%
Total125100.00%7100.00%


static void cuda_start(void) { struct adb_request *req; /* assert cuda_state == idle */ /* get the packet to send */ req = current_req; if (req == 0) return; if ((in_8(&via[B]) & TREQ) == 0) return; /* a byte is coming in from the CUDA */ /* set the shift register to shift out and send a byte */ out_8(&via[ACR], in_8(&via[ACR]) | SR_OUT); out_8(&via[SR], req->data[0]); out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = sent_first_byte; }

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Total107100.00%4100.00%


void cuda_poll(void) { /* cuda_interrupt only takes a normal lock, we disable * interrupts here to avoid re-entering and thus deadlocking. */ if (cuda_irq) disable_irq(cuda_irq); cuda_interrupt(0, NULL); if (cuda_irq) enable_irq(cuda_irq); }

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pre-gitpre-git1339.39%228.57%
finn thainfinn thain1339.39%228.57%
paul mackerraspaul mackerras618.18%228.57%
al viroal viro13.03%114.29%
Total33100.00%7100.00%

EXPORT_SYMBOL(cuda_poll);
static irqreturn_t cuda_interrupt(int irq, void *arg) { int status; struct adb_request *req = NULL; unsigned char ibuf[16]; int ibuf_len = 0; int complete = 0; spin_lock(&cuda_lock); /* On powermacs, this handler is registered for the VIA IRQ. But they use * just the shift register IRQ -- other VIA interrupt sources are disabled. * On m68k macs, the VIA IRQ sources are dispatched individually. Unless * we are polling, the shift register IRQ flag has already been cleared. */ #ifdef CONFIG_MAC if (!arg) #endif { if ((in_8(&via[IFR]) & SR_INT) == 0) { spin_unlock(&cuda_lock); return IRQ_NONE; } else { out_8(&via[IFR], SR_INT); } } status = (~in_8(&via[B]) & (TIP|TREQ)) | (in_8(&via[ACR]) & SR_OUT); /* printk("cuda_interrupt: state=%d status=%x\n", cuda_state, status); */ switch (cuda_state) { case idle: /* CUDA has sent us the first byte of data - unsolicited */ if (status != TREQ) printk("cuda: state=idle, status=%x\n", status); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = reading; reply_ptr = cuda_rbuf; reading_reply = 0; break; case awaiting_reply: /* CUDA has sent us the first byte of data of a reply */ if (status != TREQ) printk("cuda: state=awaiting_reply, status=%x\n", status); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = reading; reply_ptr = current_req->reply; reading_reply = 1; break; case sent_first_byte: if (status == TREQ + TIP + SR_OUT) { /* collision */ out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) | TIP | TACK); cuda_state = idle; } else { /* assert status == TIP + SR_OUT */ if (status != TIP + SR_OUT) printk("cuda: state=sent_first_byte status=%x\n", status); out_8(&via[SR], current_req->data[1]); out_8(&via[B], in_8(&via[B]) ^ TACK); data_index = 2; cuda_state = sending; } break; case sending: req = current_req; if (data_index >= req->nbytes) { out_8(&via[ACR], in_8(&via[ACR]) & ~SR_OUT); (void)in_8(&via[SR]); out_8(&via[B], in_8(&via[B]) | TACK | TIP); req->sent = 1; if (req->reply_expected) { cuda_state = awaiting_reply; } else { current_req = req->next; complete = 1; /* not sure about this */ cuda_state = idle; cuda_start(); } } else { out_8(&via[SR], req->data[data_index++]); out_8(&via[B], in_8(&via[B]) ^ TACK); } break; case reading: *reply_ptr++ = in_8(&via[SR]); if (status == TIP) { /* that's all folks */ out_8(&via[B], in_8(&via[B]) | TACK | TIP); cuda_state = read_done; } else { /* assert status == TIP | TREQ */ if (status != TIP + TREQ) printk("cuda: state=reading status=%x\n", status); out_8(&via[B], in_8(&via[B]) ^ TACK); } break; case read_done: (void)in_8(&via[SR]); if (reading_reply) { req = current_req; req->reply_len = reply_ptr - req->reply; if (req->data[0] == ADB_PACKET) { /* Have to adjust the reply from ADB commands */ if (req->reply_len <= 2 || (req->reply[1] & 2) != 0) { /* the 0x2 bit indicates no response */ req->reply_len = 0; } else { /* leave just the command and result bytes in the reply */ req->reply_len -= 2; memmove(req->reply, req->reply + 2, req->reply_len); } } current_req = req->next; complete = 1; } else { /* This is tricky. We must break the spinlock to call * cuda_input. However, doing so means we might get * re-entered from another CPU getting an interrupt * or calling cuda_poll(). I ended up using the stack * (it's only for 16 bytes) and moving the actual * call to cuda_input to outside of the lock. */ ibuf_len = reply_ptr - cuda_rbuf; memcpy(ibuf, cuda_rbuf, ibuf_len); } if (status == TREQ) { out_8(&via[B], in_8(&via[B]) & ~TIP); cuda_state = reading; reply_ptr = cuda_rbuf; reading_reply = 0; } else { cuda_state = idle; cuda_start(); } break; default: printk("cuda_interrupt: unknown cuda_state %d?\n", cuda_state); } spin_unlock(&cuda_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) cuda_input(ibuf, ibuf_len); return IRQ_HANDLED; }

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pre-gitpre-git54359.60%444.44%
paul mackerraspaul mackerras33837.10%333.33%
finn thainfinn thain303.29%222.22%
Total911100.00%9100.00%


static void cuda_input(unsigned char *buf, int nb) { int i; switch (buf[0]) { case ADB_PACKET: #ifdef CONFIG_XMON if (nb == 5 && buf[2] == 0x2c) { extern int xmon_wants_key, xmon_adb_keycode; if (xmon_wants_key) { xmon_adb_keycode = buf[3]; return; } } #endif /* CONFIG_XMON */ #ifdef CONFIG_ADB adb_input(buf+2, nb-2, buf[1] & 0x40); #endif /* CONFIG_ADB */ break; default: printk("data from cuda (%d bytes):", nb); for (i = 0; i < nb; ++i) printk(" %.2x", buf[i]); printk("\n"); } }

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Overall Contributors

PersonTokensPropCommitsCommitProp
pre-gitpre-git201868.80%1034.48%
paul mackerraspaul mackerras58519.95%517.24%
finn thainfinn thain1836.24%26.90%
benjamin herrenschmidtbenjamin herrenschmidt1204.09%26.90%
anton blanchardanton blanchard100.34%13.45%
geert uytterhoevengeert uytterhoeven70.24%310.34%
thomas gleixnerthomas gleixner40.14%13.45%
al viroal viro30.10%26.90%
jeremy kerrjeremy kerr10.03%13.45%
stephen rothwellstephen rothwell10.03%13.45%
linus torvaldslinus torvalds10.03%13.45%
Total2933100.00%29100.00%
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