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gxiic.c revision 1.8
      1 /*	$NetBSD: gxiic.c,v 1.8 2016/02/14 19:54:20 chs Exp $ */
      2 /*
      3  * Copyright (c) 2007 KIYOHARA Takashi
      4  * All rights reserved.
      5  *
      6  * Redistribution and use in source and binary forms, with or without
      7  * modification, are permitted provided that the following conditions
      8  * are met:
      9  * 1. Redistributions of source code must retain the above copyright
     10  *    notice, this list of conditions and the following disclaimer.
     11  * 2. Redistributions in binary form must reproduce the above copyright
     12  *    notice, this list of conditions and the following disclaimer in the
     13  *    documentation and/or other materials provided with the distribution.
     14  *
     15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
     17  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
     18  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
     19  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
     20  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
     21  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
     23  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
     24  * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     25  * POSSIBILITY OF SUCH DAMAGE.
     26  */
     27 #include <sys/cdefs.h>
     28 __KERNEL_RCSID(0, "$NetBSD: gxiic.c,v 1.8 2016/02/14 19:54:20 chs Exp $");
     29 
     30 #include <sys/param.h>
     31 #include <sys/device.h>
     32 #include <sys/errno.h>
     33 #include <sys/mutex.h>
     34 
     35 #include <arm/xscale/pxa2x0var.h>
     36 #include <arm/xscale/pxa2x0_i2c.h>
     37 
     38 #include <evbarm/gumstix/gumstixvar.h>
     39 
     40 #include <dev/i2c/i2cvar.h>
     41 
     42 
     43 struct gxiic_softc {
     44 	struct pxa2x0_i2c_softc sc_pxa_i2c;
     45 
     46 	struct i2c_controller sc_i2c;
     47 	kmutex_t sc_lock;
     48 };
     49 
     50 
     51 static int gxiicmatch(device_t, cfdata_t, void *);
     52 static void gxiicattach(device_t, device_t, void *);
     53 
     54 /* fuctions for i2c_controller */
     55 static int gxiic_acquire_bus(void *, int);
     56 static void gxiic_release_bus(void *, int);
     57 static int gxiic_exec(void *cookie, i2c_op_t, i2c_addr_t, const void *, size_t,
     58     void *, size_t, int);
     59 
     60 
     61 CFATTACH_DECL_NEW(gxiic, sizeof(struct gxiic_softc),
     62     gxiicmatch, gxiicattach, NULL, NULL);
     63 
     64 
     65 /* ARGSUSED */
     66 static int
     67 gxiicmatch(device_t parent, cfdata_t match, void *aux)
     68 {
     69 	struct pxaip_attach_args *pxa = aux;
     70 
     71 	if (strcmp(pxa->pxa_name, match->cf_name) != 0)
     72 		 return 0;
     73 
     74 	pxa->pxa_size = PXA2X0_I2C_SIZE;
     75 	return 1;
     76 }
     77 
     78 /* ARGSUSED */
     79 static void
     80 gxiicattach(device_t parent, device_t self, void *aux)
     81 {
     82 	struct pxaip_attach_args *pxa = aux;
     83 	struct gxiic_softc *sc = device_private(self);
     84 	struct i2cbus_attach_args iba;
     85 
     86 	aprint_normal("\n");
     87 	aprint_naive("\n");
     88 
     89 	sc->sc_pxa_i2c.sc_dev = self;
     90 	sc->sc_pxa_i2c.sc_iot = pxa->pxa_iot;
     91 	sc->sc_pxa_i2c.sc_addr = pxa->pxa_addr;
     92 	sc->sc_pxa_i2c.sc_size = pxa->pxa_size;
     93 	sc->sc_pxa_i2c.sc_flags = 0;
     94 	if (pxa2x0_i2c_attach_sub(&sc->sc_pxa_i2c)) {
     95 		aprint_error_dev(self, "unable to attach PXA I2C\n");
     96 		return;
     97 	}
     98 
     99 	mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE);
    100 
    101 	/* Initialize i2c_controller  */
    102 	sc->sc_i2c.ic_cookie = sc;
    103 	sc->sc_i2c.ic_acquire_bus = gxiic_acquire_bus;
    104 	sc->sc_i2c.ic_release_bus = gxiic_release_bus;
    105 	sc->sc_i2c.ic_send_start = NULL;
    106 	sc->sc_i2c.ic_send_stop = NULL;
    107 	sc->sc_i2c.ic_initiate_xfer = NULL;
    108 	sc->sc_i2c.ic_read_byte = NULL;
    109 	sc->sc_i2c.ic_write_byte = NULL;
    110 	sc->sc_i2c.ic_exec = gxiic_exec;
    111 
    112 	memset(&iba, 0, sizeof(iba));
    113 	iba.iba_tag = &sc->sc_i2c;
    114 	pxa2x0_i2c_open(&sc->sc_pxa_i2c);
    115 	config_found_ia(sc->sc_pxa_i2c.sc_dev, "i2cbus", &iba, iicbus_print);
    116 	pxa2x0_i2c_close(&sc->sc_pxa_i2c);
    117 }
    118 
    119 static int
    120 gxiic_acquire_bus(void *cookie, int flags)
    121 {
    122 	struct gxiic_softc *sc = cookie;
    123 
    124 	mutex_enter(&sc->sc_lock);
    125 	pxa2x0_i2c_open(&sc->sc_pxa_i2c);
    126 
    127 	return 0;
    128 }
    129 
    130 static void
    131 gxiic_release_bus(void *cookie, int flags)
    132 {
    133 	struct gxiic_softc *sc = cookie;
    134 
    135 	pxa2x0_i2c_close(&sc->sc_pxa_i2c);
    136 	mutex_exit(&sc->sc_lock);
    137 	return;
    138 }
    139 
    140 static int
    141 gxiic_exec(void *cookie, i2c_op_t op, i2c_addr_t addr, const void *vcmd,
    142 	   size_t cmdlen, void *vbuf, size_t buflen, int flags)
    143 {
    144 	struct gxiic_softc *sc = cookie;
    145 	int rv = -1;
    146 
    147 	if (I2C_OP_READ_P(op) && (cmdlen == 0) && (buflen == 1))
    148 		rv = pxa2x0_i2c_read(&sc->sc_pxa_i2c, addr, (u_char *)vbuf);
    149 
    150 	if ((I2C_OP_READ_P(op)) && (cmdlen == 1) && (buflen == 1)) {
    151 		rv = pxa2x0_i2c_write(&sc->sc_pxa_i2c, addr, *(u_char *)vbuf);
    152 		if (rv == 0)
    153 			rv = pxa2x0_i2c_read(&sc->sc_pxa_i2c,
    154 			    addr, (u_char *)vbuf);
    155 	}
    156 
    157 	if ((I2C_OP_READ_P(op)) && (cmdlen == 1) && (buflen == 2)) {
    158 		rv = pxa2x0_i2c_write(&sc->sc_pxa_i2c, addr, *(u_char *)vbuf);
    159 		if (rv == 0)
    160 			rv = pxa2x0_i2c_read(&sc->sc_pxa_i2c,
    161 			    addr, (u_char *)vbuf);
    162 		if (rv == 0)
    163 			rv = pxa2x0_i2c_read(&sc->sc_pxa_i2c,
    164 			    addr, (u_char *)(vbuf) + 1);
    165 	}
    166 
    167 	if ((I2C_OP_WRITE_P(op)) && (cmdlen == 0) && (buflen == 1))
    168 		rv = pxa2x0_i2c_write(&sc->sc_pxa_i2c, addr, *(u_char *)vbuf);
    169 
    170 	if ((I2C_OP_WRITE_P(op)) && (cmdlen == 1) && (buflen == 1)) {
    171 		rv = pxa2x0_i2c_write(&sc->sc_pxa_i2c,
    172 		    addr, *(const u_char *)vcmd);
    173 		if (rv == 0)
    174 			rv = pxa2x0_i2c_write(&sc->sc_pxa_i2c,
    175 			    addr, *(u_char *)vbuf);
    176 	}
    177 
    178 	if ((I2C_OP_WRITE_P(op)) && (cmdlen == 1) && (buflen == 2)) {
    179 		rv = pxa2x0_i2c_write(&sc->sc_pxa_i2c,
    180 		    addr, *(const u_char *)vcmd);
    181 		if (rv == 0)
    182 			rv = pxa2x0_i2c_write_2(&sc->sc_pxa_i2c,
    183 			    addr, *(u_short *)vbuf);
    184 	}
    185 
    186 	/* Handle quick_read/quick_write ops - XXX Untested XXX */
    187 	if ((cmdlen == 0) && (buflen == 0))
    188 		rv = pxa2x0_i2c_quick(&sc->sc_pxa_i2c, addr,
    189 			I2C_OP_READ_P(op)?1:0);
    190 
    191 	return rv;
    192 }
    193