drivers/gpio/pca953x.c

   1 /*
   2  * Copyright 2008 Extreme Engineering Solutions, Inc.
   3  *
   4  * SPDX-License-Identifier:     GPL-2.0
   5  */
   6
   7 /*
   8  * Driver for NXP's 4, 8 and 16 bit I2C gpio expanders (eg pca9537, pca9557,
   9  * pca9539, etc)
  10  */
  11
  12 #include <common.h>
  13 #include <i2c.h>
  14 #include <pca953x.h>
  15
  16 /* Default to an address that hopefully won't corrupt other i2c devices */
  17 #ifndef CONFIG_SYS_I2C_PCA953X_ADDR
  18 #define CONFIG_SYS_I2C_PCA953X_ADDR     (~0)
  19 #endif
  20
  21 enum {
  22         PCA953X_CMD_INFO,
  23         PCA953X_CMD_DEVICE,
  24         PCA953X_CMD_OUTPUT,
  25         PCA953X_CMD_INPUT,
  26         PCA953X_CMD_INVERT,
  27 };
  28
  29 #ifdef CONFIG_SYS_I2C_PCA953X_WIDTH
  30 struct pca953x_chip_ngpio {
  31         uint8_t chip;
  32         uint8_t ngpio;
  33 };
  34
  35 static struct pca953x_chip_ngpio pca953x_chip_ngpios[] =
  36     CONFIG_SYS_I2C_PCA953X_WIDTH;
  37
  38 /*
  39  * Determine the number of GPIO pins supported. If we don't know we assume
  40  * 8 pins.
  41  */
  42 static int pca953x_ngpio(uint8_t chip)
  43 {
  44         int i;
  45
  46         for (i = 0; i < ARRAY_SIZE(pca953x_chip_ngpios); i++)
  47                 if (pca953x_chip_ngpios[i].chip == chip)
  48                         return pca953x_chip_ngpios[i].ngpio;
  49
  50         return 8;
  51 }
  52 #else
  53 static int pca953x_ngpio(uint8_t chip)
  54 {
  55         return 8;
  56 }
  57 #endif
  58
  59 /*
  60  * Modify masked bits in register
  61  */
  62 static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data)
  63 {
  64         uint8_t valb;
  65         uint16_t valw;
  66
  67         if (pca953x_ngpio(chip) <= 8) {
  68                 if (i2c_read(chip, addr, 1, &valb, 1))
  69                         return -1;
  70
  71                 valb &= ~mask;
  72                 valb |= data;
  73
  74                 return i2c_write(chip, addr, 1, &valb, 1);
  75         } else {
  76                 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2))
  77                         return -1;
  78
  79                 valw = le16_to_cpu(valw);
  80                 valw &= ~mask;
  81                 valw |= data;
  82                 valw = cpu_to_le16(valw);
  83
  84                 return i2c_write(chip, addr << 1, 1, (u8*)&valw, 2);
  85         }
  86 }
  87
  88 static int pca953x_reg_read(uint8_t chip, uint addr, uint *data)
  89 {
  90         uint8_t valb;
  91         uint16_t valw;
  92
  93         if (pca953x_ngpio(chip) <= 8) {
  94                 if (i2c_read(chip, addr, 1, &valb, 1))
  95                         return -1;
  96                 *data = (int)valb;
  97         } else {
  98                 if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2))
  99                         return -1;
 100                 *data = (uint)le16_to_cpu(valw);
 101         }
 102         return 0;
 103 }
 104
 105 /*
 106  * Set output value of IO pins in 'mask' to corresponding value in 'data'
 107  * 0 = low, 1 = high
 108  */
 109 int pca953x_set_val(uint8_t chip, uint mask, uint data)
 110 {
 111         return pca953x_reg_write(chip, PCA953X_OUT, mask, data);
 112 }
 113
 114 /*
 115  * Set read polarity of IO pins in 'mask' to corresponding value in 'data'
 116  * 0 = read pin value, 1 = read inverted pin value
 117  */
 118 int pca953x_set_pol(uint8_t chip, uint mask, uint data)
 119 {
 120         return pca953x_reg_write(chip, PCA953X_POL, mask, data);
 121 }
 122
 123 /*
 124  * Set direction of IO pins in 'mask' to corresponding value in 'data'
 125  * 0 = output, 1 = input
 126  */
 127 int pca953x_set_dir(uint8_t chip, uint mask, uint data)
 128 {
 129         return pca953x_reg_write(chip, PCA953X_CONF, mask, data);
 130 }
 131
 132 /*
 133  * Read current logic level of all IO pins
 134  */
 135 int pca953x_get_val(uint8_t chip)
 136 {
 137         uint val;
 138
 139         if (pca953x_reg_read(chip, PCA953X_IN, &val) < 0)
 140                 return -1;
 141
 142         return (int)val;
 143 }
 144
 145 #ifdef CONFIG_CMD_PCA953X
 146 /*
 147  * Display pca953x information
 148  */
 149 static int pca953x_info(uint8_t chip)
 150 {
 151         int i;
 152         uint data;
 153         int nr_gpio = pca953x_ngpio(chip);
 154         int msb = nr_gpio - 1;
 155
 156         printf("pca953x@ 0x%x (%d pins):\n\n", chip, nr_gpio);
 157         printf("gpio pins: ");
 158         for (i = msb; i >= 0; i--)
 159                 printf("%x", i);
 160         printf("\n");
 161         for (i = 11 + nr_gpio; i > 0; i--)
 162                 printf("-");
 163         printf("\n");
 164
 165         if (pca953x_reg_read(chip, PCA953X_CONF, &data) < 0)
 166                 return -1;
 167         printf("conf:      ");
 168         for (i = msb; i >= 0; i--)
 169                 printf("%c", data & (1 << i) ? 'i' : 'o');
 170         printf("\n");
 171
 172         if (pca953x_reg_read(chip, PCA953X_POL, &data) < 0)
 173                 return -1;
 174         printf("invert:    ");
 175         for (i = msb; i >= 0; i--)
 176                 printf("%c", data & (1 << i) ? '1' : '0');
 177         printf("\n");
 178
 179         if (pca953x_reg_read(chip, PCA953X_IN, &data) < 0)
 180                 return -1;
 181         printf("input:     ");
 182         for (i = msb; i >= 0; i--)
 183                 printf("%c", data & (1 << i) ? '1' : '0');
 184         printf("\n");
 185
 186         if (pca953x_reg_read(chip, PCA953X_OUT, &data) < 0)
 187                 return -1;
 188         printf("output:    ");
 189         for (i = msb; i >= 0; i--)
 190                 printf("%c", data & (1 << i) ? '1' : '0');
 191         printf("\n");
 192
 193         return 0;
 194 }
 195
 196 cmd_tbl_t cmd_pca953x[] = {
 197         U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""),
 198         U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""),
 199         U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""),
 200         U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""),
 201         U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""),
 202 };
 203
 204 int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 205 {
 206         static uint8_t chip = CONFIG_SYS_I2C_PCA953X_ADDR;
 207         int ret = CMD_RET_USAGE, val;
 208         ulong ul_arg2 = 0;
 209         ulong ul_arg3 = 0;
 210         cmd_tbl_t *c;
 211
 212         c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x));
 213
 214         /* All commands but "device" require 'maxargs' arguments */
 215         if (!c || !((argc == (c->maxargs)) ||
 216                 (((long)c->cmd == PCA953X_CMD_DEVICE) &&
 217                  (argc == (c->maxargs - 1))))) {
 218                 return CMD_RET_USAGE;
 219         }
 220
 221         /* arg2 used as chip number or pin number */
 222         if (argc > 2)
 223                 ul_arg2 = simple_strtoul(argv[2], NULL, 16);
 224
 225         /* arg3 used as pin or invert value */
 226         if (argc > 3)
 227                 ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1;
 228
 229         switch ((long)c->cmd) {
 230         case PCA953X_CMD_INFO:
 231                 ret = pca953x_info(chip);
 232                 if (ret)
 233                         ret = CMD_RET_FAILURE;
 234                 break;
 235
 236         case PCA953X_CMD_DEVICE:
 237                 if (argc == 3)
 238                         chip = (uint8_t)ul_arg2;
 239                 printf("Current device address: 0x%x\n", chip);
 240                 ret = CMD_RET_SUCCESS;
 241                 break;
 242
 243         case PCA953X_CMD_INPUT:
 244                 ret = pca953x_set_dir(chip, (1 << ul_arg2),
 245                                 PCA953X_DIR_IN << ul_arg2);
 246                 val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0;
 247
 248                 if (ret)
 249                         ret = CMD_RET_FAILURE;
 250                 else
 251                         printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2,
 252                                                                         val);
 253                 break;
 254
 255         case PCA953X_CMD_OUTPUT:
 256                 ret = pca953x_set_dir(chip, (1 << ul_arg2),
 257                                 (PCA953X_DIR_OUT << ul_arg2));
 258                 if (!ret)
 259                         ret = pca953x_set_val(chip, (1 << ul_arg2),
 260                                                 (ul_arg3 << ul_arg2));
 261                 if (ret)
 262                         ret = CMD_RET_FAILURE;
 263                 break;
 264
 265         case PCA953X_CMD_INVERT:
 266                 ret = pca953x_set_pol(chip, (1 << ul_arg2),
 267                                         (ul_arg3 << ul_arg2));
 268                 if (ret)
 269                         ret = CMD_RET_FAILURE;
 270                 break;
 271         }
 272
 273         if (ret == CMD_RET_FAILURE)
 274                 eprintf("Error talking to chip at 0x%x\n", chip);
 275
 276         return ret;
 277 }
 278
 279 U_BOOT_CMD(
 280         pca953x,        5,      1,      do_pca953x,
 281         "pca953x gpio access",
 282         "device [dev]\n"
 283         "       - show or set current device address\n"
 284         "pca953x info\n"
 285         "       - display info for current chip\n"
 286         "pca953x output pin 0|1\n"
 287         "       - set pin as output and drive low or high\n"
 288         "pca953x invert pin 0|1\n"
 289         "       - disable/enable polarity inversion for reads\n"
 290         "pca953x input pin\n"
 291         "       - set pin as input and read value"
 292 );
 293
 294 #endif /* CONFIG_CMD_PCA953X */