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 = le16_to_cpu(valw); 92 valw &= ~mask; 93 valw |= data; 94 valw = cpu_to_le16(valw); 95 96 return i2c_write(chip, addr << 1, 1, (u8*)&valw, 2); 97 } 98 } 99 100 static int pca953x_reg_read(uint8_t chip, uint addr, uint *data) 101 { 102 uint8_t valb; 103 uint16_t valw; 104 105 if (pca953x_ngpio(chip) <= 8) { 106 if (i2c_read(chip, addr, 1, &valb, 1)) 107 return -1; 108 *data = (int)valb; 109 } else { 110 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2)) 111 return -1; 112 *data = (uint)le16_to_cpu(valw); 113 } 114 return 0; 115 } 116 117 /* 118 * Set output value of IO pins in 'mask' to corresponding value in 'data' 119 * 0 = low, 1 = high 120 */ 121 int pca953x_set_val(uint8_t chip, uint mask, uint data) 122 { 123 return pca953x_reg_write(chip, PCA953X_OUT, mask, data); 124 } 125 126 /* 127 * Set read polarity of IO pins in 'mask' to corresponding value in 'data' 128 * 0 = read pin value, 1 = read inverted pin value 129 */ 130 int pca953x_set_pol(uint8_t chip, uint mask, uint data) 131 { 132 return pca953x_reg_write(chip, PCA953X_POL, mask, data); 133 } 134 135 /* 136 * Set direction of IO pins in 'mask' to corresponding value in 'data' 137 * 0 = output, 1 = input 138 */ 139 int pca953x_set_dir(uint8_t chip, uint mask, uint data) 140 { 141 return pca953x_reg_write(chip, PCA953X_CONF, mask, data); 142 } 143 144 /* 145 * Read current logic level of all IO pins 146 */ 147 int pca953x_get_val(uint8_t chip) 148 { 149 uint val; 150 151 if (pca953x_reg_read(chip, PCA953X_IN, &val) < 0) 152 return -1; 153 154 return (int)val; 155 } 156 157 #ifdef CONFIG_CMD_PCA953X 158 #ifdef CONFIG_CMD_PCA953X_INFO 159 /* 160 * Display pca953x information 161 */ 162 static int pca953x_info(uint8_t chip) 163 { 164 int i; 165 uint data; 166 int nr_gpio = pca953x_ngpio(chip); 167 int msb = nr_gpio - 1; 168 169 printf("pca953x@ 0x%x (%d pins):\n\n", chip, nr_gpio); 170 printf("gpio pins: "); 171 for (i = msb; i >= 0; i--) 172 printf("%x", i); 173 printf("\n"); 174 for (i = 11 + nr_gpio; i > 0; i--) 175 printf("-"); 176 printf("\n"); 177 178 if (pca953x_reg_read(chip, PCA953X_CONF, &data) < 0) 179 return -1; 180 printf("conf: "); 181 for (i = msb; i >= 0; i--) 182 printf("%c", data & (1 << i) ? 'i' : 'o'); 183 printf("\n"); 184 185 if (pca953x_reg_read(chip, PCA953X_POL, &data) < 0) 186 return -1; 187 printf("invert: "); 188 for (i = msb; i >= 0; i--) 189 printf("%c", data & (1 << i) ? '1' : '0'); 190 printf("\n"); 191 192 if (pca953x_reg_read(chip, PCA953X_IN, &data) < 0) 193 return -1; 194 printf("input: "); 195 for (i = msb; i >= 0; i--) 196 printf("%c", data & (1 << i) ? '1' : '0'); 197 printf("\n"); 198 199 if (pca953x_reg_read(chip, PCA953X_OUT, &data) < 0) 200 return -1; 201 printf("output: "); 202 for (i = msb; i >= 0; i--) 203 printf("%c", data & (1 << i) ? '1' : '0'); 204 printf("\n"); 205 206 return 0; 207 } 208 #endif /* CONFIG_CMD_PCA953X_INFO */ 209 210 cmd_tbl_t cmd_pca953x[] = { 211 U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""), 212 U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""), 213 U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""), 214 U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""), 215 #ifdef CONFIG_CMD_PCA953X_INFO 216 U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""), 217 #endif 218 }; 219 220 int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[]) 221 { 222 static uint8_t chip = CONFIG_SYS_I2C_PCA953X_ADDR; 223 int ret = CMD_RET_USAGE, val; 224 ulong ul_arg2 = 0; 225 ulong ul_arg3 = 0; 226 cmd_tbl_t *c; 227 228 c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x)); 229 230 /* All commands but "device" require 'maxargs' arguments */ 231 if (!c || !((argc == (c->maxargs)) || 232 (((int)c->cmd == PCA953X_CMD_DEVICE) && 233 (argc == (c->maxargs - 1))))) { 234 return CMD_RET_USAGE; 235 } 236 237 /* arg2 used as chip number or pin number */ 238 if (argc > 2) 239 ul_arg2 = simple_strtoul(argv[2], NULL, 16); 240 241 /* arg3 used as pin or invert value */ 242 if (argc > 3) 243 ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1; 244 245 switch ((int)c->cmd) { 246 #ifdef CONFIG_CMD_PCA953X_INFO 247 case PCA953X_CMD_INFO: 248 ret = pca953x_info(chip); 249 if (ret) 250 ret = CMD_RET_FAILURE; 251 break; 252 #endif 253 254 case PCA953X_CMD_DEVICE: 255 if (argc == 3) 256 chip = (uint8_t)ul_arg2; 257 printf("Current device address: 0x%x\n", chip); 258 ret = CMD_RET_SUCCESS; 259 break; 260 261 case PCA953X_CMD_INPUT: 262 ret = pca953x_set_dir(chip, (1 << ul_arg2), 263 PCA953X_DIR_IN << ul_arg2); 264 val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0; 265 266 if (ret) 267 ret = CMD_RET_FAILURE; 268 else 269 printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2, 270 val); 271 break; 272 273 case PCA953X_CMD_OUTPUT: 274 ret = pca953x_set_dir(chip, (1 << ul_arg2), 275 (PCA953X_DIR_OUT << ul_arg2)); 276 if (!ret) 277 ret = pca953x_set_val(chip, (1 << ul_arg2), 278 (ul_arg3 << ul_arg2)); 279 if (ret) 280 ret = CMD_RET_FAILURE; 281 break; 282 283 case PCA953X_CMD_INVERT: 284 ret = pca953x_set_pol(chip, (1 << ul_arg2), 285 (ul_arg3 << ul_arg2)); 286 if (ret) 287 ret = CMD_RET_FAILURE; 288 break; 289 } 290 291 if (ret == CMD_RET_FAILURE) 292 eprintf("Error talking to chip at 0x%x\n", chip); 293 294 return ret; 295 } 296 297 U_BOOT_CMD( 298 pca953x, 5, 1, do_pca953x, 299 "pca953x gpio access", 300 "device [dev]\n" 301 " - show or set current device address\n" 302 #ifdef CONFIG_CMD_PCA953X_INFO 303 "pca953x info\n" 304 " - display info for current chip\n" 305 #endif 306 "pca953x output pin 0|1\n" 307 " - set pin as output and drive low or high\n" 308 "pca953x invert pin 0|1\n" 309 " - disable/enable polarity inversion for reads\n" 310 "pca953x input pin\n" 311 " - set pin as input and read value" 312 ); 313 314 #endif /* CONFIG_CMD_PCA953X */ 315