1 /* $NetBSD: i2cspi.c,v 1.1 2021/12/07 17:39:55 brad Exp $ */ 2 3 /* 4 * Copyright (c) 2021 Brad Spencer <brad@anduin.eldar.org> 5 * 6 * Permission to use, copy, modify, and distribute this software for any 7 * purpose with or without fee is hereby granted, provided that the above 8 * copyright notice and this permission notice appear in all copies. 9 * 10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 17 */ 18 19 #ifdef __RCSID 20 __RCSID("$NetBSD: i2cspi.c,v 1.1 2021/12/07 17:39:55 brad Exp $"); 21 #endif 22 23 /* Functions that know how to talk to scmd(4) */ 24 25 #include <inttypes.h> 26 #include <stdbool.h> 27 #include <stdio.h> 28 #include <stdlib.h> 29 #include <unistd.h> 30 #include <err.h> 31 #include <fcntl.h> 32 #include <string.h> 33 #include <limits.h> 34 #include <errno.h> 35 36 #include <dev/ic/scmdreg.h> 37 38 #include "scmdctl.h" 39 #include "responses.h" 40 41 #define EXTERN 42 #include "i2cspi.h" 43 44 int i2cspi_clear(int, bool); 45 int i2cspi_read_register(int, bool, int, uint8_t, uint8_t, uint8_t *); 46 int i2cspi_write_register(int, bool, int, uint8_t, uint8_t); 47 48 49 /* The scmd(4) presents the register space as a linear chunk that can 50 * be seek to read and written to without any real messing around 51 */ 52 static int 53 i2cspi_phy_read_register(int fd, bool debug, uint8_t reg, int rlen, uint8_t *buf) 54 { 55 int err; 56 57 if (rlen <= 0) 58 return EINVAL; 59 60 err = lseek(fd, reg, SEEK_SET); 61 if (err != -1) { 62 err = read(fd, buf, rlen); 63 if (err == -1) 64 err = errno; 65 else 66 err = 0; 67 } else { 68 err = errno; 69 } 70 71 if (debug) 72 fprintf(stderr,"i2cspi_phy_read_register: reg: 0x%02X: rlen: %d: return err: %d\n",reg, rlen, err); 73 74 return err; 75 } 76 77 static int 78 i2cspi_phy_write_register(int fd, bool debug, uint8_t reg, uint8_t buf) 79 { 80 int err; 81 82 err = lseek(fd, reg, SEEK_SET); 83 if (err != -1) { 84 err = write(fd, &buf, 1); 85 if (err == -1) 86 err = errno; 87 else 88 err = 0; 89 } else { 90 err = errno; 91 } 92 93 if (debug) 94 fprintf(stderr,"i2cspi_phy_write_register: reg: 0x%02X: return err: %d\n",reg, err); 95 96 return err; 97 } 98 99 int 100 i2cspi_clear(int fd, bool debug) 101 { 102 return 0; 103 } 104 105 int 106 i2cspi_read_register(int fd, bool debug, int a_module, uint8_t reg, uint8_t reg_end, uint8_t *r) 107 { 108 if (reg > SCMD_LAST_REG || 109 reg_end > SCMD_LAST_REG) 110 return EINVAL; 111 112 if (reg_end < reg) 113 return EINVAL; 114 115 if (debug) 116 fprintf(stderr,"i2cspi_read_register: reg: %d ; reg_rend: %d ; rlen: %d\n",reg, reg_end, reg_end - reg + 1); 117 118 return i2cspi_phy_read_register(fd, debug, reg + (SCMD_REG_SIZE * a_module), reg_end - reg + 1, r); 119 } 120 121 int 122 i2cspi_write_register(int fd, bool debug, int a_module, uint8_t reg, uint8_t reg_v) 123 { 124 int err; 125 126 if (reg > SCMD_LAST_REG) 127 return EINVAL; 128 129 err = i2cspi_phy_write_register(fd, debug, reg + (SCMD_REG_SIZE * a_module), reg_v); 130 131 return err; 132 } 133