Fixed MTP to work with TWRP

drivers/macintosh/via-cuda.c

@@ -0,0 +1,641 @@
+/*
+ * 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;
+}
+#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;
+}
+#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;
+}
+
+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;
+}
+#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;
+}
+
+#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;
+}
+
+
+/* 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;
+}
+
+/* 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;
+}
+#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);
+}
+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;
+}
+
+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;
+}
+
+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);
+}
+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;
+}
+
+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");
+    }
+}