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armadillo9_iic.c revision 1.9
      1 /*	$NetBSD: armadillo9_iic.c,v 1.9 2019/12/22 23:23:30 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2005 HAMAJIMA Katsuomi. 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 AND CONTRIBUTORS ``AS IS'' AND
     16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     25  * SUCH DAMAGE.
     26  */
     27 
     28 #include <sys/cdefs.h>
     29 __KERNEL_RCSID(0, "$NetBSD: armadillo9_iic.c,v 1.9 2019/12/22 23:23:30 thorpej Exp $");
     30 
     31 #include <sys/param.h>
     32 #include <sys/systm.h>
     33 #include <sys/kernel.h>
     34 #include <sys/device.h>
     35 #include <sys/mutex.h>
     36 #include <dev/i2c/i2cvar.h>
     37 #include <dev/i2c/i2c_bitbang.h>
     38 #include <arm/ep93xx/epsocvar.h>
     39 #include <arm/ep93xx/epgpiovar.h>
     40 #include <evbarm/armadillo/armadillo9var.h>
     41 
     42 #include "seeprom.h"
     43 #if NSEEPROM > 0
     44 #include <net/if.h>
     45 #include <net/if_ether.h>
     46 #include <dev/i2c/at24cxxvar.h>
     47 #endif
     48 
     49 struct armadillo9iic_softc {
     50 	struct i2c_controller	sc_i2c;
     51 	int			sc_port;
     52 	int			sc_sda;
     53 	int			sc_scl;
     54 	struct epgpio_softc	*sc_gpio;
     55 };
     56 
     57 static int armadillo9iic_match(device_t, cfdata_t, void *);
     58 static void armadillo9iic_attach(device_t, device_t, void *);
     59 
     60 static int armadillo9iic_send_start(void *, int);
     61 static int armadillo9iic_send_stop(void *, int);
     62 static int armadillo9iic_initiate_xfer(void *, uint16_t, int);
     63 static int armadillo9iic_read_byte(void *, uint8_t *, int);
     64 static int armadillo9iic_write_byte(void *, uint8_t, int);
     65 
     66 static void armadillo9iic_bb_set_bits(void *, uint32_t);
     67 static void armadillo9iic_bb_set_dir(void *, uint32_t);
     68 static uint32_t armadillo9iic_bb_read_bits(void *);
     69 
     70 CFATTACH_DECL_NEW(armadillo9iic, sizeof(struct armadillo9iic_softc),
     71 	      armadillo9iic_match, armadillo9iic_attach, NULL, NULL);
     72 
     73 static struct i2c_bitbang_ops armadillo9iic_bbops = {
     74 	armadillo9iic_bb_set_bits,
     75 	armadillo9iic_bb_set_dir,
     76 	armadillo9iic_bb_read_bits,
     77 	{ 0, 0, 0, 0 }	/* set in attach() */
     78 };
     79 
     80 int
     81 armadillo9iic_match(device_t parent, cfdata_t cf, void *aux)
     82 {
     83 	return 2;
     84 }
     85 
     86 void
     87 armadillo9iic_attach(device_t parent, device_t self, void *aux)
     88 {
     89 	struct armadillo9iic_softc *sc = device_private(self);
     90 	struct i2cbus_attach_args iba;
     91 #if NSEEPROM > 0
     92 	struct epgpio_attach_args *ga = aux;
     93 #endif
     94 
     95 	sc->sc_port = ga->ga_port;
     96 	sc->sc_sda = ga->ga_bit1;
     97 	sc->sc_scl = ga->ga_bit2;
     98 	sc->sc_gpio = (struct epgpio_softc *)parent;
     99 
    100 	armadillo9iic_bbops.ibo_bits[I2C_BIT_SDA] = (1<<sc->sc_sda);
    101 	armadillo9iic_bbops.ibo_bits[I2C_BIT_SCL] = (1<<sc->sc_scl);
    102 	armadillo9iic_bbops.ibo_bits[I2C_BIT_OUTPUT] = sc->sc_sda;
    103 	armadillo9iic_bbops.ibo_bits[I2C_BIT_INPUT] = 0;
    104 
    105 	iic_tag_init(&sc->sc_i2c);
    106 	sc->sc_i2c.ic_cookie = sc;
    107 	sc->sc_i2c.ic_send_start = armadillo9iic_send_start;
    108 	sc->sc_i2c.ic_send_stop = armadillo9iic_send_stop;
    109 	sc->sc_i2c.ic_initiate_xfer = armadillo9iic_initiate_xfer;
    110 	sc->sc_i2c.ic_read_byte = armadillo9iic_read_byte;
    111 	sc->sc_i2c.ic_write_byte = armadillo9iic_write_byte;
    112 
    113 	memset(&iba, 0, sizeof(iba));
    114 	iba.iba_tag = &sc->sc_i2c;
    115 
    116 	epgpio_in(sc->sc_gpio, sc->sc_port, sc->sc_sda);
    117 	epgpio_out(sc->sc_gpio, sc->sc_port, sc->sc_scl);
    118 	epgpio_set(sc->sc_gpio, sc->sc_port, sc->sc_scl);
    119 
    120 	printf("\n");
    121 
    122 	config_found_ia(self, "i2cbus", &iba, iicbus_print);
    123 
    124 #if NSEEPROM > 0
    125 	/* read mac address */
    126 	/* XXX This should probably be done elsewhere, earlier in bootstrap. */
    127 	if (seeprom_bootstrap_read(&sc->sc_i2c, 0x50, 0x00, 128,
    128 				   armadillo9_ethaddr, ETHER_ADDR_LEN) != 0) {
    129 		printf("%s: WARNING: unable to read MAC address from SEEPROM\n",
    130 		    device_xname(self));
    131 	}
    132 #endif
    133 }
    134 
    135 int
    136 armadillo9iic_send_start(void *cookie, int flags)
    137 {
    138 	return i2c_bitbang_send_start(cookie, flags, &armadillo9iic_bbops);
    139 }
    140 
    141 int
    142 armadillo9iic_send_stop(void *cookie, int flags)
    143 {
    144 	return i2c_bitbang_send_stop(cookie, flags, &armadillo9iic_bbops);
    145 }
    146 
    147 int
    148 armadillo9iic_initiate_xfer(void *cookie, i2c_addr_t addr, int flags)
    149 {
    150 	return i2c_bitbang_initiate_xfer(cookie, addr, flags,
    151 					 &armadillo9iic_bbops);
    152 }
    153 
    154 int
    155 armadillo9iic_read_byte(void *cookie, uint8_t *bytep, int flags)
    156 {
    157 	return i2c_bitbang_read_byte(cookie, bytep, flags,
    158 				     &armadillo9iic_bbops);
    159 }
    160 
    161 int
    162 armadillo9iic_write_byte(void *cookie, uint8_t byte, int flags)
    163 {
    164 	return i2c_bitbang_write_byte(cookie, byte, flags,
    165 				      &armadillo9iic_bbops);
    166 }
    167 
    168 void
    169 armadillo9iic_bb_set_bits(void *cookie, uint32_t bits)
    170 {
    171 	struct armadillo9iic_softc *sc = cookie;
    172 
    173 	if (bits & (1 << sc->sc_sda))
    174 		epgpio_set(sc->sc_gpio, sc->sc_port, sc->sc_sda);
    175 	else
    176 		epgpio_clear(sc->sc_gpio, sc->sc_port, sc->sc_sda);
    177 
    178 	if (bits & (1 << sc->sc_scl))
    179 		epgpio_set(sc->sc_gpio, sc->sc_port, sc->sc_scl);
    180 	else
    181 		epgpio_clear(sc->sc_gpio, sc->sc_port, sc->sc_scl);
    182 }
    183 
    184 void
    185 armadillo9iic_bb_set_dir(void *cookie, uint32_t bits)
    186 {
    187 	struct armadillo9iic_softc *sc = cookie;
    188 
    189 	if(bits)
    190 		epgpio_out(sc->sc_gpio, sc->sc_port, sc->sc_sda);
    191 	else
    192 		epgpio_in(sc->sc_gpio, sc->sc_port, sc->sc_sda);
    193 }
    194 
    195 uint32_t
    196 armadillo9iic_bb_read_bits(void *cookie)
    197 {
    198 	struct armadillo9iic_softc *sc = cookie;
    199 	uint32_t bits = 0;
    200 
    201 	bits |= epgpio_read(sc->sc_gpio, sc->sc_port, sc->sc_sda) << sc->sc_sda;
    202 	bits |= epgpio_read(sc->sc_gpio, sc->sc_port, sc->sc_scl) << sc->sc_scl;
    203 
    204 	return bits;
    205 }
    206