1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2008 Extreme Engineering Solutions, Inc.
4  */
5 
6 /*
7  * Driver for NXP's 4, 8 and 16 bit I2C gpio expanders (eg pca9537, pca9557,
8  * pca9539, etc)
9  */
10 
11 #include <config.h>
12 #include <command.h>
13 #include <i2c.h>
14 #include <pca953x.h>
15 #include <vsprintf.h>
16 #include <asm/byteorder.h>
17 
18 /* Default to an address that hopefully won't corrupt other i2c devices */
19 #ifndef CFG_SYS_I2C_PCA953X_ADDR
20 #define CFG_SYS_I2C_PCA953X_ADDR	(~0)
21 #endif
22 
23 enum {
24 	PCA953X_CMD_INFO,
25 	PCA953X_CMD_DEVICE,
26 	PCA953X_CMD_OUTPUT,
27 	PCA953X_CMD_INPUT,
28 	PCA953X_CMD_INVERT,
29 };
30 
31 #ifdef CFG_SYS_I2C_PCA953X_WIDTH
32 struct pca953x_chip_ngpio {
33 	uint8_t chip;
34 	uint8_t ngpio;
35 };
36 
37 static struct pca953x_chip_ngpio pca953x_chip_ngpios[] =
38     CFG_SYS_I2C_PCA953X_WIDTH;
39 
40 /*
41  * Determine the number of GPIO pins supported. If we don't know we assume
42  * 8 pins.
43  */
pca953x_ngpio(uint8_t chip)44 static int pca953x_ngpio(uint8_t chip)
45 {
46 	int i;
47 
48 	for (i = 0; i < ARRAY_SIZE(pca953x_chip_ngpios); i++)
49 		if (pca953x_chip_ngpios[i].chip == chip)
50 			return pca953x_chip_ngpios[i].ngpio;
51 
52 	return 8;
53 }
54 #else
pca953x_ngpio(uint8_t chip)55 static int pca953x_ngpio(uint8_t chip)
56 {
57 	return 8;
58 }
59 #endif
60 
61 /*
62  * Modify masked bits in register
63  */
pca953x_reg_write(uint8_t chip,uint addr,uint mask,uint data)64 static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data)
65 {
66 	uint8_t valb;
67 	uint16_t valw;
68 
69 	if (pca953x_ngpio(chip) <= 8) {
70 		if (i2c_read(chip, addr, 1, &valb, 1))
71 			return -1;
72 
73 		valb &= ~mask;
74 		valb |= data;
75 
76 		return i2c_write(chip, addr, 1, &valb, 1);
77 	} else {
78 		if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2))
79 			return -1;
80 
81 		valw = le16_to_cpu(valw);
82 		valw &= ~mask;
83 		valw |= data;
84 		valw = cpu_to_le16(valw);
85 
86 		return i2c_write(chip, addr << 1, 1, (u8*)&valw, 2);
87 	}
88 }
89 
pca953x_reg_read(uint8_t chip,uint addr,uint * data)90 static int pca953x_reg_read(uint8_t chip, uint addr, uint *data)
91 {
92 	uint8_t valb;
93 	uint16_t valw;
94 
95 	if (pca953x_ngpio(chip) <= 8) {
96 		if (i2c_read(chip, addr, 1, &valb, 1))
97 			return -1;
98 		*data = (int)valb;
99 	} else {
100 		if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2))
101 			return -1;
102 		*data = (uint)le16_to_cpu(valw);
103 	}
104 	return 0;
105 }
106 
107 /*
108  * Set output value of IO pins in 'mask' to corresponding value in 'data'
109  * 0 = low, 1 = high
110  */
pca953x_set_val(uint8_t chip,uint mask,uint data)111 int pca953x_set_val(uint8_t chip, uint mask, uint data)
112 {
113 	return pca953x_reg_write(chip, PCA953X_OUT, mask, data);
114 }
115 
116 /*
117  * Set read polarity of IO pins in 'mask' to corresponding value in 'data'
118  * 0 = read pin value, 1 = read inverted pin value
119  */
pca953x_set_pol(uint8_t chip,uint mask,uint data)120 int pca953x_set_pol(uint8_t chip, uint mask, uint data)
121 {
122 	return pca953x_reg_write(chip, PCA953X_POL, mask, data);
123 }
124 
125 /*
126  * Set direction of IO pins in 'mask' to corresponding value in 'data'
127  * 0 = output, 1 = input
128  */
pca953x_set_dir(uint8_t chip,uint mask,uint data)129 int pca953x_set_dir(uint8_t chip, uint mask, uint data)
130 {
131 	return pca953x_reg_write(chip, PCA953X_CONF, mask, data);
132 }
133 
134 /*
135  * Read current logic level of all IO pins
136  */
pca953x_get_val(uint8_t chip)137 int pca953x_get_val(uint8_t chip)
138 {
139 	uint val;
140 
141 	if (pca953x_reg_read(chip, PCA953X_IN, &val) < 0)
142 		return -1;
143 
144 	return (int)val;
145 }
146 
147 #if defined(CONFIG_CMD_PCA953X) && !defined(CONFIG_XPL_BUILD)
148 /*
149  * Display pca953x information
150  */
pca953x_info(uint8_t chip)151 static int pca953x_info(uint8_t chip)
152 {
153 	int i;
154 	uint data;
155 	int nr_gpio = pca953x_ngpio(chip);
156 	int msb = nr_gpio - 1;
157 
158 	printf("pca953x@ 0x%x (%d pins):\n\n", chip, nr_gpio);
159 	printf("gpio pins: ");
160 	for (i = msb; i >= 0; i--)
161 		printf("%x", i);
162 	printf("\n");
163 	for (i = 11 + nr_gpio; i > 0; i--)
164 		printf("-");
165 	printf("\n");
166 
167 	if (pca953x_reg_read(chip, PCA953X_CONF, &data) < 0)
168 		return -1;
169 	printf("conf:      ");
170 	for (i = msb; i >= 0; i--)
171 		printf("%c", data & (1 << i) ? 'i' : 'o');
172 	printf("\n");
173 
174 	if (pca953x_reg_read(chip, PCA953X_POL, &data) < 0)
175 		return -1;
176 	printf("invert:    ");
177 	for (i = msb; i >= 0; i--)
178 		printf("%c", data & (1 << i) ? '1' : '0');
179 	printf("\n");
180 
181 	if (pca953x_reg_read(chip, PCA953X_IN, &data) < 0)
182 		return -1;
183 	printf("input:     ");
184 	for (i = msb; i >= 0; i--)
185 		printf("%c", data & (1 << i) ? '1' : '0');
186 	printf("\n");
187 
188 	if (pca953x_reg_read(chip, PCA953X_OUT, &data) < 0)
189 		return -1;
190 	printf("output:    ");
191 	for (i = msb; i >= 0; i--)
192 		printf("%c", data & (1 << i) ? '1' : '0');
193 	printf("\n");
194 
195 	return 0;
196 }
197 
198 static struct cmd_tbl cmd_pca953x[] = {
199 	U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""),
200 	U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""),
201 	U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""),
202 	U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""),
203 	U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""),
204 };
205 
do_pca953x(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])206 static int do_pca953x(struct cmd_tbl *cmdtp, int flag, int argc,
207 		      char *const argv[])
208 {
209 	static uint8_t chip = CFG_SYS_I2C_PCA953X_ADDR;
210 	int ret = CMD_RET_USAGE, val;
211 	ulong ul_arg2 = 0;
212 	ulong ul_arg3 = 0;
213 	struct cmd_tbl *c;
214 
215 	c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x));
216 
217 	/* All commands but "device" require 'maxargs' arguments */
218 	if (!c || !((argc == (c->maxargs)) ||
219 		(((long)c->cmd == PCA953X_CMD_DEVICE) &&
220 		 (argc == (c->maxargs - 1))))) {
221 		return CMD_RET_USAGE;
222 	}
223 
224 	/* arg2 used as chip number or pin number */
225 	if (argc > 2)
226 		ul_arg2 = hextoul(argv[2], NULL);
227 
228 	/* arg3 used as pin or invert value */
229 	if (argc > 3)
230 		ul_arg3 = hextoul(argv[3], NULL) & 0x1;
231 
232 	switch ((long)c->cmd) {
233 	case PCA953X_CMD_INFO:
234 		ret = pca953x_info(chip);
235 		if (ret)
236 			ret = CMD_RET_FAILURE;
237 		break;
238 
239 	case PCA953X_CMD_DEVICE:
240 		if (argc == 3)
241 			chip = (uint8_t)ul_arg2;
242 		printf("Current device address: 0x%x\n", chip);
243 		ret = CMD_RET_SUCCESS;
244 		break;
245 
246 	case PCA953X_CMD_INPUT:
247 		ret = pca953x_set_dir(chip, (1 << ul_arg2),
248 				PCA953X_DIR_IN << ul_arg2);
249 		val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0;
250 
251 		if (ret)
252 			ret = CMD_RET_FAILURE;
253 		else
254 			printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2,
255 									val);
256 		break;
257 
258 	case PCA953X_CMD_OUTPUT:
259 		ret = pca953x_set_dir(chip, (1 << ul_arg2),
260 				(PCA953X_DIR_OUT << ul_arg2));
261 		if (!ret)
262 			ret = pca953x_set_val(chip, (1 << ul_arg2),
263 						(ul_arg3 << ul_arg2));
264 		if (ret)
265 			ret = CMD_RET_FAILURE;
266 		break;
267 
268 	case PCA953X_CMD_INVERT:
269 		ret = pca953x_set_pol(chip, (1 << ul_arg2),
270 					(ul_arg3 << ul_arg2));
271 		if (ret)
272 			ret = CMD_RET_FAILURE;
273 		break;
274 	}
275 
276 	if (ret == CMD_RET_FAILURE)
277 		eprintf("Error talking to chip at 0x%x\n", chip);
278 
279 	return ret;
280 }
281 
282 U_BOOT_CMD(
283 	pca953x,	5,	1,	do_pca953x,
284 	"pca953x gpio access",
285 	"device [dev]\n"
286 	"	- show or set current device address\n"
287 	"pca953x info\n"
288 	"	- display info for current chip\n"
289 	"pca953x output pin 0|1\n"
290 	"	- set pin as output and drive low or high\n"
291 	"pca953x invert pin 0|1\n"
292 	"	- disable/enable polarity inversion for reads\n"
293 	"pca953x input pin\n"
294 	"	- set pin as input and read value"
295 );
296 
297 #endif /* CONFIG_CMD_PCA953X */
298