1 /* 2 * Copyright 2008 Extreme Engineering Solutions, Inc. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * Version 2 as published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program; if not, write to the Free Software 15 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 16 * MA 02111-1307 USA 17 */ 18 19 /* 20 * Driver for NXP's 4 and 8 bit I2C gpio expanders (eg pca9537, pca9557, etc) 21 * TODO: support additional devices with more than 8-bits GPIO 22 */ 23 24 #include <common.h> 25 #include <i2c.h> 26 #include <pca953x.h> 27 28 /* Default to an address that hopefully won't corrupt other i2c devices */ 29 #ifndef CONFIG_SYS_I2C_PCA953X_ADDR 30 #define CONFIG_SYS_I2C_PCA953X_ADDR (~0) 31 #endif 32 33 enum { 34 PCA953X_CMD_INFO, 35 PCA953X_CMD_DEVICE, 36 PCA953X_CMD_OUTPUT, 37 PCA953X_CMD_INPUT, 38 PCA953X_CMD_INVERT, 39 }; 40 41 /* 42 * Modify masked bits in register 43 */ 44 static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data) 45 { 46 uint8_t val; 47 48 if (i2c_read(chip, addr, 1, &val, 1)) 49 return -1; 50 51 val &= ~mask; 52 val |= data; 53 54 return i2c_write(chip, addr, 1, &val, 1); 55 } 56 57 /* 58 * Set output value of IO pins in 'mask' to corresponding value in 'data' 59 * 0 = low, 1 = high 60 */ 61 int pca953x_set_val(uint8_t chip, uint mask, uint data) 62 { 63 return pca953x_reg_write(chip, PCA953X_OUT, mask, data); 64 } 65 66 /* 67 * Set read polarity of IO pins in 'mask' to corresponding value in 'data' 68 * 0 = read pin value, 1 = read inverted pin value 69 */ 70 int pca953x_set_pol(uint8_t chip, uint mask, uint data) 71 { 72 return pca953x_reg_write(chip, PCA953X_POL, mask, data); 73 } 74 75 /* 76 * Set direction of IO pins in 'mask' to corresponding value in 'data' 77 * 0 = output, 1 = input 78 */ 79 int pca953x_set_dir(uint8_t chip, uint mask, uint data) 80 { 81 return pca953x_reg_write(chip, PCA953X_CONF, mask, data); 82 } 83 84 /* 85 * Read current logic level of all IO pins 86 */ 87 int pca953x_get_val(uint8_t chip) 88 { 89 uint8_t val; 90 91 if (i2c_read(chip, 0, 1, &val, 1)) 92 return -1; 93 94 return (int)val; 95 } 96 97 #ifdef CONFIG_CMD_PCA953X 98 #ifdef CONFIG_CMD_PCA953X_INFO 99 /* 100 * Display pca953x information 101 */ 102 static int pca953x_info(uint8_t chip) 103 { 104 int i; 105 uint8_t data; 106 107 printf("pca953x@ 0x%x:\n\n", chip); 108 printf("gpio pins: 76543210\n"); 109 printf("-------------------\n"); 110 111 if (i2c_read(chip, PCA953X_CONF, 1, &data, 1)) 112 return -1; 113 printf("conf: "); 114 for (i = 7; i >= 0; i--) 115 printf("%c", data & (1 << i) ? 'i' : 'o'); 116 printf("\n"); 117 118 if (i2c_read(chip, PCA953X_POL, 1, &data, 1)) 119 return -1; 120 printf("invert: "); 121 for (i = 7; i >= 0; i--) 122 printf("%c", data & (1 << i) ? '1' : '0'); 123 printf("\n"); 124 125 if (i2c_read(chip, PCA953X_IN, 1, &data, 1)) 126 return -1; 127 printf("input: "); 128 for (i = 7; i >= 0; i--) 129 printf("%c", data & (1 << i) ? '1' : '0'); 130 printf("\n"); 131 132 if (i2c_read(chip, PCA953X_OUT, 1, &data, 1)) 133 return -1; 134 printf("output: "); 135 for (i = 7; i >= 0; i--) 136 printf("%c", data & (1 << i) ? '1' : '0'); 137 printf("\n"); 138 139 return 0; 140 } 141 #endif /* CONFIG_CMD_PCA953X_INFO */ 142 143 cmd_tbl_t cmd_pca953x[] = { 144 U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""), 145 U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""), 146 U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""), 147 U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""), 148 #ifdef CONFIG_CMD_PCA953X_INFO 149 U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""), 150 #endif 151 }; 152 153 int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]) 154 { 155 static uint8_t chip = CONFIG_SYS_I2C_PCA953X_ADDR; 156 int val; 157 ulong ul_arg2 = 0; 158 ulong ul_arg3 = 0; 159 cmd_tbl_t *c; 160 161 c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x)); 162 163 /* All commands but "device" require 'maxargs' arguments */ 164 if (!c || !((argc == (c->maxargs)) || 165 (((int)c->cmd == PCA953X_CMD_DEVICE) && 166 (argc == (c->maxargs - 1))))) { 167 cmd_usage(cmdtp); 168 return 1; 169 } 170 171 /* arg2 used as chip number or pin number */ 172 if (argc > 2) 173 ul_arg2 = simple_strtoul(argv[2], NULL, 16); 174 175 /* arg3 used as pin or invert value */ 176 if (argc > 3) 177 ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1; 178 179 switch ((int)c->cmd) { 180 #ifdef CONFIG_CMD_PCA953X_INFO 181 case PCA953X_CMD_INFO: 182 return pca953x_info(chip); 183 #endif 184 case PCA953X_CMD_DEVICE: 185 if (argc == 3) 186 chip = (uint8_t)ul_arg2; 187 printf("Current device address: 0x%x\n", chip); 188 return 0; 189 case PCA953X_CMD_INPUT: 190 pca953x_set_dir(chip, (1 << ul_arg2), 191 PCA953X_DIR_IN << ul_arg2); 192 val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0; 193 194 printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2, val); 195 return val; 196 case PCA953X_CMD_OUTPUT: 197 pca953x_set_dir(chip, (1 << ul_arg2), 198 (PCA953X_DIR_OUT << ul_arg2)); 199 return pca953x_set_val(chip, (1 << ul_arg2), 200 (ul_arg3 << ul_arg2)); 201 case PCA953X_CMD_INVERT: 202 return pca953x_set_pol(chip, (1 << ul_arg2), 203 (ul_arg3 << ul_arg2)); 204 default: 205 /* We should never get here */ 206 return 1; 207 } 208 } 209 210 U_BOOT_CMD( 211 pca953x, 5, 1, do_pca953x, 212 "pca953x gpio access", 213 "device [dev]\n" 214 " - show or set current device address\n" 215 #ifdef CONFIG_CMD_PCA953X_INFO 216 "pca953x info\n" 217 " - display info for current chip\n" 218 #endif 219 "pca953x output pin 0|1\n" 220 " - set pin as output and drive low or high\n" 221 "pca953x invert pin 0|1\n" 222 " - disable/enable polarity inversion for reads\n" 223 "pca953x intput pin\n" 224 " - set pin as input and read value" 225 ); 226 227 #endif /* CONFIG_CMD_PCA953X */ 228