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      1 /*	$NetBSD: pca9564.c,v 1.6 2025/09/15 13:23:03 thorpej Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2010 NONAKA Kimihiro <nonaka (at) netbsd.org>
      5  * All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  *
     16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     26  */
     27 
     28 #include <sys/cdefs.h>
     29 __KERNEL_RCSID(0, "$NetBSD: pca9564.c,v 1.6 2025/09/15 13:23:03 thorpej Exp $");
     30 
     31 #include <sys/param.h>
     32 #include <sys/device.h>
     33 #include <sys/mutex.h>
     34 #include <sys/bus.h>
     35 
     36 #include <dev/i2c/i2cvar.h>
     37 
     38 #include <dev/ic/pca9564reg.h>
     39 #include <dev/ic/pca9564var.h>
     40 
     41 #if defined(PCA9564_DEBUG)
     42 int pca9564debug = 0;
     43 #define	DPRINTF(s)	if (pca9564debug) printf s
     44 #else
     45 #define	DPRINTF(s)
     46 #endif
     47 
     48 static int pca9564_acquire_bus(void *, int);
     49 static void pca9564_release_bus(void *, int);
     50 
     51 static int pca9564_send_start(void *, int);
     52 static int pca9564_send_stop(void *, int);
     53 static int pca9564_initiate_xfer(void *, uint16_t, int);
     54 static int pca9564_read_byte(void *, uint8_t *, int);
     55 static int pca9564_write_byte(void *, uint8_t, int);
     56 
     57 static int pca9564_ack(void *, bool, int);
     58 
     59 #define	CSR_READ(sc, r)		(*sc->sc_ios.read_byte)(sc->sc_dev, r)
     60 #define	CSR_WRITE(sc, r, v)	(*sc->sc_ios.write_byte)(sc->sc_dev, r, v)
     61 
     62 void
     63 pca9564_attach(struct pca9564_softc *sc)
     64 {
     65 
     66 	aprint_naive("\n");
     67 	aprint_normal(": PCA9564 I2C Controller\n");
     68 
     69 	iic_tag_init(&sc->sc_i2c);
     70 	sc->sc_i2c.ic_cookie = sc;
     71 	sc->sc_i2c.ic_acquire_bus = pca9564_acquire_bus;
     72 	sc->sc_i2c.ic_release_bus = pca9564_release_bus;
     73 	sc->sc_i2c.ic_send_start = pca9564_send_start;
     74 	sc->sc_i2c.ic_send_stop = pca9564_send_stop;
     75 	sc->sc_i2c.ic_initiate_xfer = pca9564_initiate_xfer;
     76 	sc->sc_i2c.ic_read_byte = pca9564_read_byte;
     77 	sc->sc_i2c.ic_write_byte = pca9564_write_byte;
     78 
     79 	/* set serial clock rate */
     80 	switch (sc->sc_i2c_clock) {
     81 	case 330000:	/* 330kHz */
     82 		sc->sc_i2c_clock = I2CCON_CR_330KHZ;
     83 		break;
     84 	case 288000:	/* 288kHz */
     85 		sc->sc_i2c_clock = I2CCON_CR_288KHZ;
     86 		break;
     87 	case 217000:	/* 217kHz */
     88 		sc->sc_i2c_clock = I2CCON_CR_217KHZ;
     89 		break;
     90 	case 146000:	/* 146kHz */
     91 		sc->sc_i2c_clock = I2CCON_CR_146KHZ;
     92 		break;
     93 	case 88000:	/* 88kHz */
     94 		sc->sc_i2c_clock = I2CCON_CR_88KHZ;
     95 		break;
     96 	case 0:		/* default */
     97 	case 59000:	/* 59kHz */
     98 		sc->sc_i2c_clock = I2CCON_CR_59KHZ;
     99 		break;
    100 	case 44000:	/* 44kHz */
    101 		sc->sc_i2c_clock = I2CCON_CR_44KHZ;
    102 		break;
    103 	case 36000:	/* 36kHz */
    104 		sc->sc_i2c_clock = I2CCON_CR_36KHZ;
    105 		break;
    106 	default:
    107 		aprint_error_dev(sc->sc_dev, "unknown i2c clock %dHz\n",
    108 		    sc->sc_i2c_clock);
    109 		sc->sc_i2c_clock = I2CCON_CR_59KHZ;
    110 		break;
    111 	}
    112 
    113 	iicbus_attach(sc->sc_dev, &sc->sc_i2c);
    114 }
    115 
    116 static int
    117 pca9564_acquire_bus(void *cookie, int flags)
    118 {
    119 	struct pca9564_softc *sc = cookie;
    120 	uint8_t control;
    121 
    122 	/* Enable SIO and set clock */
    123 	control = CSR_READ(sc, PCA9564_I2CCON);
    124 	control |= I2CCON_ENSIO;
    125 	control &= ~(I2CCON_STA|I2CCON_STO|I2CCON_SI|I2CCON_AA);
    126 	control &= ~I2CCON_CR_MASK;
    127 	control |= sc->sc_i2c_clock;
    128 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    129 	delay(500);
    130 
    131 	return 0;
    132 }
    133 
    134 static void
    135 pca9564_release_bus(void *cookie, int flags)
    136 {
    137 	struct pca9564_softc *sc = cookie;
    138 	uint8_t control;
    139 
    140 	/* Disable SIO */
    141 	control = CSR_READ(sc, PCA9564_I2CCON);
    142 	control &= ~I2CCON_ENSIO;
    143 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    144 }
    145 
    146 #define	PCA9564_TIMEOUT		100	/* protocol timeout, in uSecs */
    147 
    148 static int
    149 pca9564_wait(struct pca9564_softc *sc, int flags)
    150 {
    151 	int timeout;
    152 
    153 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    154 	for (timeout = PCA9564_TIMEOUT; timeout > 0; timeout--) {
    155 		if (CSR_READ(sc, PCA9564_I2CCON) & I2CCON_SI)
    156 			break;
    157 		delay(1);
    158 	}
    159 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    160 	if (timeout == 0) {
    161 		aprint_error_dev(sc->sc_dev, "timeout\n");
    162 		return ETIMEDOUT;
    163 	}
    164 	return 0;
    165 }
    166 
    167 static int
    168 pca9564_send_start(void *cookie, int flags)
    169 {
    170 	struct pca9564_softc *sc = cookie;
    171 	uint8_t control;
    172 
    173 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    174 	control = CSR_READ(sc, PCA9564_I2CCON);
    175 	control |= I2CCON_STA;
    176 	control &= ~(I2CCON_STO|I2CCON_SI);
    177 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    178 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    179 
    180 	return pca9564_wait(sc, flags);
    181 }
    182 
    183 static int
    184 pca9564_send_stop(void *cookie, int flags)
    185 {
    186 	struct pca9564_softc *sc = cookie;
    187 	uint8_t control;
    188 
    189 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    190 	control = CSR_READ(sc, PCA9564_I2CCON);
    191 	control |= I2CCON_STO;
    192 	control &= ~(I2CCON_STA|I2CCON_SI);
    193 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    194 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    195 
    196 	return 0;
    197 }
    198 
    199 static int
    200 pca9564_initiate_xfer(void *cookie, uint16_t addr, int flags)
    201 {
    202 	struct pca9564_softc *sc = cookie;
    203 	int error, rd_req = (flags & I2C_F_READ) != 0;
    204 	uint8_t data, control;
    205 
    206 	error = pca9564_send_start(sc, flags);
    207 	if (error) {
    208 		aprint_error_dev(sc->sc_dev, "failed to send start %s xfer\n",
    209 		    rd_req ? "read" : "write");
    210 		return error;
    211 	}
    212 
    213 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    214 	control = CSR_READ(sc, PCA9564_I2CCON);
    215 
    216 	data = (addr << 1) | (rd_req ? 1 : 0);
    217 	CSR_WRITE(sc, PCA9564_I2CDAT, data);
    218 
    219 	control &= ~(I2CCON_STO|I2CCON_STA|I2CCON_SI);
    220 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    221 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    222 
    223 	error = pca9564_wait(sc, flags);
    224 	if (error)
    225 		aprint_error_dev(sc->sc_dev, "failed to initiate %s xfer\n",
    226 		    rd_req ? "read" : "write");
    227 	return error;
    228 }
    229 
    230 static int
    231 pca9564_read_byte(void *cookie, uint8_t *bytep, int flags)
    232 {
    233 	struct pca9564_softc *sc = cookie;
    234 	int send_stop = (flags & I2C_F_STOP) != 0;
    235 	int error;
    236 
    237 	error = pca9564_ack(sc, !send_stop, flags);
    238 	if (error) {
    239 		aprint_error_dev(sc->sc_dev, "failed to ack\n");
    240 		return error;
    241 	}
    242 
    243 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    244 	*bytep = CSR_READ(sc, PCA9564_I2CDAT);
    245 	DPRINTF(("%s: status=%#x, byte=%#x\n", __func__,
    246 	    CSR_READ(sc, PCA9564_I2CSTA), *bytep));
    247 
    248 	if (send_stop)
    249 		pca9564_send_stop(sc, flags);
    250 
    251 	return 0;
    252 }
    253 
    254 static int
    255 pca9564_write_byte(void *cookie, uint8_t byte, int flags)
    256 {
    257 	struct pca9564_softc *sc = cookie;
    258 	int send_stop = (flags & I2C_F_STOP) != 0;
    259 	int error;
    260 	uint8_t control;
    261 
    262 	DPRINTF(("%s: status=%#x, byte=%#x\n", __func__,
    263 	    CSR_READ(sc, PCA9564_I2CSTA), byte));
    264 	control = CSR_READ(sc, PCA9564_I2CCON);
    265 
    266 	CSR_WRITE(sc, PCA9564_I2CDAT, byte);
    267 
    268 	control &= ~(I2CCON_STO|I2CCON_STA|I2CCON_SI);
    269 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    270 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    271 
    272 	error = pca9564_wait(sc, flags);
    273 	if (error)
    274 		aprint_error_dev(sc->sc_dev, "write byte failed\n");
    275 
    276 	if (send_stop)
    277 		pca9564_send_stop(sc, flags);
    278 
    279 	return error;
    280 }
    281 
    282 static int
    283 pca9564_ack(void *cookie, bool ack, int flags)
    284 {
    285 	struct pca9564_softc *sc = cookie;
    286 	uint8_t control;
    287 
    288 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    289 	control = CSR_READ(sc, PCA9564_I2CCON);
    290 	control &= ~(I2CCON_STO|I2CCON_STA|I2CCON_SI|I2CCON_AA);
    291 	if (ack)
    292 		control |= I2CCON_AA;
    293 	CSR_WRITE(sc, PCA9564_I2CCON, control);
    294 	DPRINTF(("%s: status=%#x\n", __func__, CSR_READ(sc, PCA9564_I2CSTA)));
    295 
    296 	return pca9564_wait(sc, flags);
    297 }
    298