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, 8 and 16 bit I2C gpio expanders (eg pca9537, pca9557, 21 * pca9539, etc) 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 #ifdef CONFIG_SYS_I2C_PCA953X_WIDTH 42 struct pca953x_chip_ngpio { 43 uint8_t chip; 44 uint8_t ngpio; 45 }; 46 47 static struct pca953x_chip_ngpio pca953x_chip_ngpios[] = 48 CONFIG_SYS_I2C_PCA953X_WIDTH; 49 50 /* 51 * Determine the number of GPIO pins supported. If we don't know we assume 52 * 8 pins. 53 */ 54 static int pca953x_ngpio(uint8_t chip) 55 { 56 int i; 57 58 for (i = 0; i < ARRAY_SIZE(pca953x_chip_ngpios); i++) 59 if (pca953x_chip_ngpios[i].chip == chip) 60 return pca953x_chip_ngpios[i].ngpio; 61 62 return 8; 63 } 64 #else 65 static int pca953x_ngpio(uint8_t chip) 66 { 67 return 8; 68 } 69 #endif 70 71 /* 72 * Modify masked bits in register 73 */ 74 static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data) 75 { 76 uint8_t valb; 77 uint16_t valw; 78 79 if (pca953x_ngpio(chip) <= 8) { 80 if (i2c_read(chip, addr, 1, &valb, 1)) 81 return -1; 82 83 valb &= ~mask; 84 valb |= data; 85 86 return i2c_write(chip, addr, 1, &valb, 1); 87 } else { 88 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2)) 89 return -1; 90 91 valw &= ~mask; 92 valw |= data; 93 94 return i2c_write(chip, addr << 1, 1, (u8*)&valw, 2); 95 } 96 } 97 98 static int pca953x_reg_read(uint8_t chip, uint addr, uint *data) 99 { 100 uint8_t valb; 101 uint16_t valw; 102 103 if (pca953x_ngpio(chip) <= 8) { 104 if (i2c_read(chip, addr, 1, &valb, 1)) 105 return -1; 106 *data = (int)valb; 107 } else { 108 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2)) 109 return -1; 110 *data = (int)valw; 111 } 112 return 0; 113 } 114 115 /* 116 * Set output value of IO pins in 'mask' to corresponding value in 'data' 117 * 0 = low, 1 = high 118 */ 119 int pca953x_set_val(uint8_t chip, uint mask, uint data) 120 { 121 return pca953x_reg_write(chip, PCA953X_OUT, mask, data); 122 } 123 124 /* 125 * Set read polarity of IO pins in 'mask' to corresponding value in 'data' 126 * 0 = read pin value, 1 = read inverted pin value 127 */ 128 int pca953x_set_pol(uint8_t chip, uint mask, uint data) 129 { 130 return pca953x_reg_write(chip, PCA953X_POL, mask, data); 131 } 132 133 /* 134 * Set direction of IO pins in 'mask' to corresponding value in 'data' 135 * 0 = output, 1 = input 136 */ 137 int pca953x_set_dir(uint8_t chip, uint mask, uint data) 138 { 139 return pca953x_reg_write(chip, PCA953X_CONF, mask, data); 140 } 141 142 /* 143 * Read current logic level of all IO pins 144 */ 145 int pca953x_get_val(uint8_t chip) 146 { 147 uint val; 148 149 if (pca953x_reg_read(chip, PCA953X_IN, &val) < 0) 150 return -1; 151 152 return (int)val; 153 } 154 155 #ifdef CONFIG_CMD_PCA953X 156 #ifdef CONFIG_CMD_PCA953X_INFO 157 /* 158 * Display pca953x information 159 */ 160 static int pca953x_info(uint8_t chip) 161 { 162 int i; 163 uint data; 164 int nr_gpio = pca953x_ngpio(chip); 165 int msb = nr_gpio - 1; 166 167 printf("pca953x@ 0x%x (%d pins):\n\n", chip, nr_gpio); 168 printf("gpio pins: "); 169 for (i = msb; i >= 0; i--) 170 printf("%x", i); 171 printf("\n"); 172 for (i = 11 + nr_gpio; i > 0; i--) 173 printf("-"); 174 printf("\n"); 175 176 if (pca953x_reg_read(chip, PCA953X_CONF, &data) < 0) 177 return -1; 178 printf("conf: "); 179 for (i = msb; i >= 0; i--) 180 printf("%c", data & (1 << i) ? 'i' : 'o'); 181 printf("\n"); 182 183 if (pca953x_reg_read(chip, PCA953X_POL, &data) < 0) 184 return -1; 185 printf("invert: "); 186 for (i = msb; i >= 0; i--) 187 printf("%c", data & (1 << i) ? '1' : '0'); 188 printf("\n"); 189 190 if (pca953x_reg_read(chip, PCA953X_IN, &data) < 0) 191 return -1; 192 printf("input: "); 193 for (i = msb; i >= 0; i--) 194 printf("%c", data & (1 << i) ? '1' : '0'); 195 printf("\n"); 196 197 if (pca953x_reg_read(chip, PCA953X_OUT, &data) < 0) 198 return -1; 199 printf("output: "); 200 for (i = msb; i >= 0; i--) 201 printf("%c", data & (1 << i) ? '1' : '0'); 202 printf("\n"); 203 204 return 0; 205 } 206 #endif /* CONFIG_CMD_PCA953X_INFO */ 207 208 cmd_tbl_t cmd_pca953x[] = { 209 U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""), 210 U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""), 211 U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""), 212 U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""), 213 #ifdef CONFIG_CMD_PCA953X_INFO 214 U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""), 215 #endif 216 }; 217 218 int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) 219 { 220 static uint8_t chip = CONFIG_SYS_I2C_PCA953X_ADDR; 221 int ret = CMD_RET_USAGE, val; 222 ulong ul_arg2 = 0; 223 ulong ul_arg3 = 0; 224 cmd_tbl_t *c; 225 226 c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x)); 227 228 /* All commands but "device" require 'maxargs' arguments */ 229 if (!c || !((argc == (c->maxargs)) || 230 (((int)c->cmd == PCA953X_CMD_DEVICE) && 231 (argc == (c->maxargs - 1))))) { 232 return CMD_RET_USAGE; 233 } 234 235 /* arg2 used as chip number or pin number */ 236 if (argc > 2) 237 ul_arg2 = simple_strtoul(argv[2], NULL, 16); 238 239 /* arg3 used as pin or invert value */ 240 if (argc > 3) 241 ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1; 242 243 switch ((int)c->cmd) { 244 #ifdef CONFIG_CMD_PCA953X_INFO 245 case PCA953X_CMD_INFO: 246 ret = pca953x_info(chip); 247 if (ret) 248 ret = CMD_RET_FAILURE; 249 break; 250 #endif 251 252 case PCA953X_CMD_DEVICE: 253 if (argc == 3) 254 chip = (uint8_t)ul_arg2; 255 printf("Current device address: 0x%x\n", chip); 256 ret = CMD_RET_SUCCESS; 257 break; 258 259 case PCA953X_CMD_INPUT: 260 ret = pca953x_set_dir(chip, (1 << ul_arg2), 261 PCA953X_DIR_IN << ul_arg2); 262 val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0; 263 264 if (ret) 265 ret = CMD_RET_FAILURE; 266 else 267 printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2, 268 val); 269 break; 270 271 case PCA953X_CMD_OUTPUT: 272 ret = pca953x_set_dir(chip, (1 << ul_arg2), 273 (PCA953X_DIR_OUT << ul_arg2)); 274 if (!ret) 275 ret = pca953x_set_val(chip, (1 << ul_arg2), 276 (ul_arg3 << ul_arg2)); 277 if (ret) 278 ret = CMD_RET_FAILURE; 279 break; 280 281 case PCA953X_CMD_INVERT: 282 ret = pca953x_set_pol(chip, (1 << ul_arg2), 283 (ul_arg3 << ul_arg2)); 284 if (ret) 285 ret = CMD_RET_FAILURE; 286 break; 287 } 288 289 if (ret == CMD_RET_FAILURE) 290 eprintf("Error talking to chip at 0x%x\n", chip); 291 292 return ret; 293 } 294 295 U_BOOT_CMD( 296 pca953x, 5, 1, do_pca953x, 297 "pca953x gpio access", 298 "device [dev]\n" 299 " - show or set current device address\n" 300 #ifdef CONFIG_CMD_PCA953X_INFO 301 "pca953x info\n" 302 " - display info for current chip\n" 303 #endif 304 "pca953x output pin 0|1\n" 305 " - set pin as output and drive low or high\n" 306 "pca953x invert pin 0|1\n" 307 " - disable/enable polarity inversion for reads\n" 308 "pca953x input pin\n" 309 " - set pin as input and read value" 310 ); 311 312 #endif /* CONFIG_CMD_PCA953X */ 313