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 #define NUM_CHIP_GPIOS (sizeof(pca953x_chip_ngpios) / \ 51 sizeof(struct pca953x_chip_ngpio)) 52 53 /* 54 * Determine the number of GPIO pins supported. If we don't know we assume 55 * 8 pins. 56 */ 57 static int pca953x_ngpio(uint8_t chip) 58 { 59 int i; 60 61 for (i = 0; i < NUM_CHIP_GPIOS; i++) 62 if (pca953x_chip_ngpios[i].chip == chip) 63 return pca953x_chip_ngpios[i].ngpio; 64 65 return 8; 66 } 67 #else 68 static int pca953x_ngpio(uint8_t chip) 69 { 70 return 8; 71 } 72 #endif 73 74 /* 75 * Modify masked bits in register 76 */ 77 static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data) 78 { 79 uint8_t valb; 80 uint16_t valw; 81 82 if (pca953x_ngpio(chip) <= 8) { 83 if (i2c_read(chip, addr, 1, &valb, 1)) 84 return -1; 85 86 valb &= ~mask; 87 valb |= data; 88 89 return i2c_write(chip, addr, 1, &valb, 1); 90 } else { 91 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2)) 92 return -1; 93 94 valw &= ~mask; 95 valw |= data; 96 97 return i2c_write(chip, addr << 1, 1, (u8*)&valw, 2); 98 } 99 } 100 101 static int pca953x_reg_read(uint8_t chip, uint addr, uint *data) 102 { 103 uint8_t valb; 104 uint16_t valw; 105 106 if (pca953x_ngpio(chip) <= 8) { 107 if (i2c_read(chip, addr, 1, &valb, 1)) 108 return -1; 109 *data = (int)valb; 110 } else { 111 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2)) 112 return -1; 113 *data = (int)valw; 114 } 115 return 0; 116 } 117 118 /* 119 * Set output value of IO pins in 'mask' to corresponding value in 'data' 120 * 0 = low, 1 = high 121 */ 122 int pca953x_set_val(uint8_t chip, uint mask, uint data) 123 { 124 return pca953x_reg_write(chip, PCA953X_OUT, mask, data); 125 } 126 127 /* 128 * Set read polarity of IO pins in 'mask' to corresponding value in 'data' 129 * 0 = read pin value, 1 = read inverted pin value 130 */ 131 int pca953x_set_pol(uint8_t chip, uint mask, uint data) 132 { 133 return pca953x_reg_write(chip, PCA953X_POL, mask, data); 134 } 135 136 /* 137 * Set direction of IO pins in 'mask' to corresponding value in 'data' 138 * 0 = output, 1 = input 139 */ 140 int pca953x_set_dir(uint8_t chip, uint mask, uint data) 141 { 142 return pca953x_reg_write(chip, PCA953X_CONF, mask, data); 143 } 144 145 /* 146 * Read current logic level of all IO pins 147 */ 148 int pca953x_get_val(uint8_t chip) 149 { 150 uint val; 151 152 if (pca953x_reg_read(chip, PCA953X_IN, &val) < 0) 153 return -1; 154 155 return (int)val; 156 } 157 158 #ifdef CONFIG_CMD_PCA953X 159 #ifdef CONFIG_CMD_PCA953X_INFO 160 /* 161 * Display pca953x information 162 */ 163 static int pca953x_info(uint8_t chip) 164 { 165 int i; 166 uint data; 167 int nr_gpio = pca953x_ngpio(chip); 168 int msb = nr_gpio - 1; 169 170 printf("pca953x@ 0x%x (%d pins):\n\n", chip, nr_gpio); 171 printf("gpio pins: "); 172 for (i = msb; i >= 0; i--) 173 printf("%x", i); 174 printf("\n"); 175 for (i = 11 + nr_gpio; i > 0; i--) 176 printf("-"); 177 printf("\n"); 178 179 if (pca953x_reg_read(chip, PCA953X_CONF, &data) < 0) 180 return -1; 181 printf("conf: "); 182 for (i = msb; i >= 0; i--) 183 printf("%c", data & (1 << i) ? 'i' : 'o'); 184 printf("\n"); 185 186 if (pca953x_reg_read(chip, PCA953X_POL, &data) < 0) 187 return -1; 188 printf("invert: "); 189 for (i = msb; i >= 0; i--) 190 printf("%c", data & (1 << i) ? '1' : '0'); 191 printf("\n"); 192 193 if (pca953x_reg_read(chip, PCA953X_IN, &data) < 0) 194 return -1; 195 printf("input: "); 196 for (i = msb; i >= 0; i--) 197 printf("%c", data & (1 << i) ? '1' : '0'); 198 printf("\n"); 199 200 if (pca953x_reg_read(chip, PCA953X_OUT, &data) < 0) 201 return -1; 202 printf("output: "); 203 for (i = msb; i >= 0; i--) 204 printf("%c", data & (1 << i) ? '1' : '0'); 205 printf("\n"); 206 207 return 0; 208 } 209 #endif /* CONFIG_CMD_PCA953X_INFO */ 210 211 cmd_tbl_t cmd_pca953x[] = { 212 U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""), 213 U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""), 214 U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""), 215 U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""), 216 #ifdef CONFIG_CMD_PCA953X_INFO 217 U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""), 218 #endif 219 }; 220 221 int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) 222 { 223 static uint8_t chip = CONFIG_SYS_I2C_PCA953X_ADDR; 224 int ret = CMD_RET_USAGE, val; 225 ulong ul_arg2 = 0; 226 ulong ul_arg3 = 0; 227 cmd_tbl_t *c; 228 229 c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x)); 230 231 /* All commands but "device" require 'maxargs' arguments */ 232 if (!c || !((argc == (c->maxargs)) || 233 (((int)c->cmd == PCA953X_CMD_DEVICE) && 234 (argc == (c->maxargs - 1))))) { 235 return CMD_RET_USAGE; 236 } 237 238 /* arg2 used as chip number or pin number */ 239 if (argc > 2) 240 ul_arg2 = simple_strtoul(argv[2], NULL, 16); 241 242 /* arg3 used as pin or invert value */ 243 if (argc > 3) 244 ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1; 245 246 switch ((int)c->cmd) { 247 #ifdef CONFIG_CMD_PCA953X_INFO 248 case PCA953X_CMD_INFO: 249 ret = pca953x_info(chip); 250 if (ret) 251 ret = CMD_RET_FAILURE; 252 break; 253 #endif 254 255 case PCA953X_CMD_DEVICE: 256 if (argc == 3) 257 chip = (uint8_t)ul_arg2; 258 printf("Current device address: 0x%x\n", chip); 259 ret = CMD_RET_SUCCESS; 260 break; 261 262 case PCA953X_CMD_INPUT: 263 ret = pca953x_set_dir(chip, (1 << ul_arg2), 264 PCA953X_DIR_IN << ul_arg2); 265 val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0; 266 267 if (ret) 268 ret = CMD_RET_FAILURE; 269 else 270 printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2, 271 val); 272 break; 273 274 case PCA953X_CMD_OUTPUT: 275 ret = pca953x_set_dir(chip, (1 << ul_arg2), 276 (PCA953X_DIR_OUT << ul_arg2)); 277 if (!ret) 278 ret = pca953x_set_val(chip, (1 << ul_arg2), 279 (ul_arg3 << ul_arg2)); 280 if (ret) 281 ret = CMD_RET_FAILURE; 282 break; 283 284 case PCA953X_CMD_INVERT: 285 ret = pca953x_set_pol(chip, (1 << ul_arg2), 286 (ul_arg3 << ul_arg2)); 287 if (ret) 288 ret = CMD_RET_FAILURE; 289 break; 290 } 291 292 if (ret == CMD_RET_FAILURE) 293 eprintf("Error talking to chip at 0x%x\n", chip); 294 295 return ret; 296 } 297 298 U_BOOT_CMD( 299 pca953x, 5, 1, do_pca953x, 300 "pca953x gpio access", 301 "device [dev]\n" 302 " - show or set current device address\n" 303 #ifdef CONFIG_CMD_PCA953X_INFO 304 "pca953x info\n" 305 " - display info for current chip\n" 306 #endif 307 "pca953x output pin 0|1\n" 308 " - set pin as output and drive low or high\n" 309 "pca953x invert pin 0|1\n" 310 " - disable/enable polarity inversion for reads\n" 311 "pca953x input pin\n" 312 " - set pin as input and read value" 313 ); 314 315 #endif /* CONFIG_CMD_PCA953X */ 316