/*- * Copyright (c) 1998 Nicolas Souchu, Marc Bouget * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $Id: pcf.c,v 1.1.1.17 1998/08/29 17:04:23 son Exp $ * */ #include #include #include #include #include #include #include #include #include #include #include "iicbus_if.h" #define TIMEOUT 99999 /* XXX */ /* Status bits of S1 register (read only) */ #define nBB 0x01 /* busy when low set/reset by STOP/START*/ #define LAB 0x02 /* lost arbitration bit in multi-master mode */ #define AAS 0x04 /* addressed as slave */ #define LRB 0x08 /* last received byte when not AAS */ #define AD0 0x08 /* general call received when AAS */ #define BER 0x10 /* bus error, misplaced START or STOP */ #define STS 0x20 /* STOP detected in slave receiver mode */ #define PIN 0x80 /* pending interrupt not (r/w) */ /* Control bits of S1 register (write only) */ #define ACK 0x01 #define STO 0x02 #define STA 0x04 #define ENI 0x08 #define ES2 0x10 #define ES1 0x20 #define ES0 0x40 #define BUFSIZE 2048 #define SLAVE_TRANSMITTER 0x1 #define SLAVE_RECEIVER 0x2 struct pcf_softc { int pcf_base; /* isa port */ int pcf_count; int pcf_own_address; /* own address */ int pcf_slave_mode; /* receiver or transmitter */ device_t iicbus; /* the corresponding iicbus */ }; struct pcf_isa_softc { int pcf_unit; /* unit of the isa device */ int pcf_base; /* isa port */ int pcf_irq; /* isa irq or null if polled */ unsigned int pcf_flags; /* boot flags */ }; #define MAXPCF 2 static struct pcf_isa_softc *pcfdata[MAXPCF]; static npcf = 0; static int pcfprobe_isa(struct isa_device *); static int pcfattach_isa(struct isa_device *); struct isa_driver pcfdriver = { pcfprobe_isa, pcfattach_isa, "pcf" }; static int pcf_probe(device_t); static int pcf_attach(device_t); static void pcf_print_child(device_t, device_t); static int pcf_repeated_start(device_t, u_char); static int pcf_start(device_t, u_char); static int pcf_stop(device_t); static int pcf_write(device_t, char *, int, int *); static int pcf_read(device_t, char *, int, int *); static int pcf_rst_card(device_t, u_char); static device_method_t pcf_methods[] = { /* device interface */ DEVMETHOD(device_probe, pcf_probe), DEVMETHOD(device_attach, pcf_attach), /* bus interface */ DEVMETHOD(bus_print_child, pcf_print_child), /* iicbus interface */ DEVMETHOD(iicbus_repeated_start, pcf_repeated_start), DEVMETHOD(iicbus_start, pcf_start), DEVMETHOD(iicbus_stop, pcf_stop), DEVMETHOD(iicbus_write, pcf_write), DEVMETHOD(iicbus_read, pcf_read), DEVMETHOD(iicbus_reset, pcf_rst_card), { 0, 0 } }; static driver_t pcf_driver = { "pcf", pcf_methods, DRIVER_TYPE_MISC, sizeof(struct pcf_softc), }; static devclass_t pcf_devclass; #define DEVTOSOFTC(dev) ((struct pcf_softc *)device_get_softc(dev)) static int pcfprobe_isa(struct isa_device *dvp) { device_t pcfdev; struct pcf_isa_softc *pcf; int error; if (npcf >= MAXPCF) return (0); if ((pcf = (struct pcf_isa_softc *)malloc(sizeof(struct pcf_isa_softc), M_DEVBUF, M_NOWAIT)) == NULL) return (0); pcf->pcf_base = dvp->id_iobase; /* XXX should be ivars */ pcf->pcf_unit = dvp->id_unit; if (!(dvp->id_flags & IIC_POLLED)) pcf->pcf_irq = (dvp->id_irq); pcfdata[npcf++] = pcf; /* XXX add the pcf device to the root_bus until isa bus exists */ pcfdev = device_add_child(root_bus, "pcf", pcf->pcf_unit, NULL); if (!pcfdev) goto error; end_probe: return (1); error: free(pcf, M_DEVBUF); return (0); } static int pcfattach_isa(struct isa_device *isdp) { return (1); /* ok */ } static int pcf_probe(device_t pcfdev) { struct pcf_softc *pcf = (struct pcf_softc *)device_get_softc(pcfdev); /* XXX try do detect chipset */ device_set_desc(pcfdev, "PCF8584 I2C bus controller"); pcf->iicbus = iicbus_alloc_bus(pcfdev); if (!pcf->iicbus) return (EINVAL); return (0); } static int pcf_attach(device_t pcfdev) { struct pcf_softc *pcf = (struct pcf_softc *)device_get_softc(pcfdev); int unit = device_get_unit(pcfdev); /* retrieve base address from isa initialization * * XXX should use ivars with isabus */ pcf->pcf_base = pcfdata[unit]->pcf_base; /* probe and attach the iicbus */ device_probe_and_attach(pcf->iicbus); return (0); } static void pcf_print_child(device_t bus, device_t dev) { printf(" on %s%d addr 0x%x", device_get_name(bus), device_get_unit(bus), iicbus_get_own_address(dev)); return; } /* * PCF8584 datasheet : when operate at 8 MHz or more, a minimun time of * 6 clocks cycles must be left between two consecutives access */ #define pcf_nops() DELAY(10) #define dummy_read(pcf) PCF_GET_S0(pcf) #define dummy_write(pcf) PCF_SET_S0(pcf, 0) /* * Specific register access to PCF8584 */ static void PCF_SET_S0(struct pcf_softc *pcf, int data) { outb(pcf->pcf_base, data); pcf_nops(); } static void PCF_SET_S1(struct pcf_softc *pcf, int data) { outb(pcf->pcf_base+1, data); pcf_nops(); } static char PCF_GET_S0(struct pcf_softc *pcf) { char data; data = inb(pcf->pcf_base); pcf_nops(); return (data); } static char PCF_GET_S1(struct pcf_softc *pcf) { char data; data = inb(pcf->pcf_base+1); pcf_nops(); return (data); } /* * Polling mode for master operations wait for a new * byte incomming or outgoing */ static int pcf_wait_byte(struct pcf_softc *pcf) { int counter = TIMEOUT; while (counter--) { if ((PCF_GET_S1(pcf) & PIN) == 0) return (0); } return (IIC_ETIMEOUT); } static int pcf_stop(device_t pcfdev) { struct pcf_softc *pcf = DEVTOSOFTC(pcfdev); /* set stop condition and enable IT */ PCF_SET_S1(pcf, PIN|ES0|ENI|STO|ACK); return (0); } static int pcf_repeated_start(device_t pcfdev, u_char slave) { struct pcf_softc *pcf = DEVTOSOFTC(pcfdev); int error = 0; /* repeated start */ PCF_SET_S1(pcf, ES0|STA|STO|ACK); /* set slave address to PCF. Last bit (LSB) must be set correctly * according to transfer direction */ PCF_SET_S0(pcf, slave); /* wait for address sent, polling */ if ((error = pcf_wait_byte(pcf))) goto error; /* check ACK */ if (PCF_GET_S1(pcf) & LRB) { error = IIC_ENOACK; goto error; } return (0); error: pcf_stop(pcfdev); return (error); } static int pcf_start(device_t pcfdev, u_char slave) { struct pcf_softc *pcf = DEVTOSOFTC(pcfdev); int error = 0; if (PCF_GET_S1(pcf) & nBB == 0) return (IIC_EBUSBSY); /* set slave address to PCF. Last bit (LSB) must be set correctly * according to transfer direction */ PCF_SET_S0(pcf, slave); /* START only */ PCF_SET_S1(pcf, PIN|ES0|STA|ACK); /* wait for address sent, polling */ if ((error = pcf_wait_byte(pcf))) goto error; /* check ACK */ if (PCF_GET_S1(pcf) & LRB) { error = IIC_ENOACK; goto error; } return (0); error: pcf_stop(pcfdev); return (error); } void pcfintr(unit) { struct pcf_softc *pcf = (struct pcf_softc *)devclass_get_softc(pcf_devclass, unit); char data, status, addr; char error = 0; status = PCF_GET_S1(pcf); if (status & PIN) { printf("pcf%d: spurious interrupt, status=0x%x\n", unit, status & 0xff); goto error; } if (status & LAB) printf("pcf%d: bus arbitration lost!\n", unit); if (status & BER) { error = IIC_EBUSERR; iicbus_intr(pcf->iicbus, INTR_ERROR, &error); goto error; } do { status = PCF_GET_S1(pcf); switch(pcf->pcf_slave_mode) { case SLAVE_TRANSMITTER: if (status & LRB) { /* ack interrupt line */ dummy_write(pcf); /* no ack, don't send anymore */ pcf->pcf_slave_mode = SLAVE_RECEIVER; iicbus_intr(pcf->iicbus, INTR_NOACK, NULL); break; } /* get data from upper code */ iicbus_intr(pcf->iicbus, INTR_TRANSMIT, &data); PCF_SET_S0(pcf, data); break; case SLAVE_RECEIVER: if (status & AAS) { addr = PCF_GET_S0(pcf); if (status & AD0) iicbus_intr(pcf->iicbus, INTR_GENERAL, &addr); else iicbus_intr(pcf->iicbus, INTR_START, &addr); if (addr & LSB) { pcf->pcf_slave_mode = SLAVE_TRANSMITTER; /* get the first char from upper code */ iicbus_intr(pcf->iicbus, INTR_TRANSMIT, &data); /* send first data byte */ PCF_SET_S0(pcf, data); } break; } /* stop condition received? */ if (status & STS) { /* ack interrupt line */ dummy_read(pcf); /* emulate intr stop condition */ iicbus_intr(pcf->iicbus, INTR_STOP, NULL); } else { /* get data, ack interrupt line */ data = PCF_GET_S0(pcf); /* deliver the character */ iicbus_intr(pcf->iicbus, INTR_RECEIVE, &data); } break; default: panic("%s: unknown slave mode (%d)!", __FUNCTION__, pcf->pcf_slave_mode); } } while ((PCF_GET_S1(pcf) & PIN) == 0); return; error: /* unknown event on bus...reset PCF */ PCF_SET_S1(pcf, PIN|ES0|ENI|ACK); pcf->pcf_slave_mode = SLAVE_RECEIVER; return; } static int pcf_rst_card(device_t pcfdev, u_char speed) { struct pcf_softc *pcf = DEVTOSOFTC(pcfdev); u_char ownaddr; /* retrieve own address from bus level */ if ((ownaddr = iicbus_get_own_address(pcf->iicbus)) == 0) ownaddr = 0xaa; PCF_SET_S1(pcf, PIN); /* initialize S1 */ /* own address S'O<>0 */ PCF_SET_S0(pcf, ownaddr >> 1); /* select clock register */ PCF_SET_S1(pcf, PIN|ES1); /* select bus speed : 18=90kb, 19=45kb, 1A=11kb, 1B=1.5kb */ switch (speed) { case IIC_SLOW: PCF_SET_S0(pcf, 0x1b); break; case IIC_FAST: PCF_SET_S0(pcf, 0x19); break; case IIC_UNKNOWN: case IIC_FASTEST: default: PCF_SET_S0(pcf, 0x18); break; } /* set bus on, ack=yes, INT=yes */ PCF_SET_S1(pcf, PIN|ES0|ENI|ACK); pcf->pcf_slave_mode = SLAVE_RECEIVER; return (0); } static int pcf_write(device_t pcfdev, char *buf, int len, int *sent) { struct pcf_softc *pcf = DEVTOSOFTC(pcfdev); int bytes, error = 0; #ifdef PCFDEBUG printf("pcf%d: >> writing %d bytes\n", device_get_unit(pcfdev), len); #endif bytes = 0; while (len) { PCF_SET_S0(pcf, *buf++); if ((error = pcf_wait_byte(pcf))) goto error; if (PCF_GET_S1(pcf) & LRB) { error = IIC_ENOACK; goto error; } len --; bytes ++; } error: *sent = bytes; #ifdef PCFDEBUG printf("pcf%d: >> %d bytes written (%d)\n", device_get_unit(pcfdev), bytes, error); #endif return (error); } static int pcf_read(device_t pcfdev, char *buf, int len, int *read) { struct pcf_softc *pcf = DEVTOSOFTC(pcfdev); int bytes, error = 0; #ifdef PCFDEBUG printf("pcf%d: << reading %d bytes\n", device_get_unit(pcfdev), len); #endif /* trig the bus to get the first data byte in S0 */ if (len) { if (len == 1) /* just one byte to read */ PCF_SET_S1(pcf, ES0); /* no ack */ dummy_read(pcf); } bytes = 0; while (len) { if ((error = pcf_wait_byte(pcf))) { pcf_stop(pcfdev); goto error; } if (len == 1) { /* ok, last data byte already in S0 */ pcf_stop(pcfdev); *buf = PCF_GET_S0(pcf); } else { if (len == 2) /* next trigged byte with no ack */ PCF_SET_S1(pcf, ES0); /* read last data byte, trig for next data byte */ *buf++ = PCF_GET_S0(pcf); } len --; bytes ++; }; error: *read = bytes; #ifdef PCFDEBUG printf("pcf%d: << %d bytes read (%d)\n", device_get_unit(pcfdev), bytes, error); #endif return (error); } DRIVER_MODULE(pcf, root, pcf_driver, pcf_devclass, 0, 0);