xref: /openbmc/u-boot/drivers/gpio/pca953x.c (revision e8f80a5a)
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 <common.h>
12 #include <i2c.h>
13 #include <pca953x.h>
14 
15 /* Default to an address that hopefully won't corrupt other i2c devices */
16 #ifndef CONFIG_SYS_I2C_PCA953X_ADDR
17 #define CONFIG_SYS_I2C_PCA953X_ADDR	(~0)
18 #endif
19 
20 enum {
21 	PCA953X_CMD_INFO,
22 	PCA953X_CMD_DEVICE,
23 	PCA953X_CMD_OUTPUT,
24 	PCA953X_CMD_INPUT,
25 	PCA953X_CMD_INVERT,
26 };
27 
28 #ifdef CONFIG_SYS_I2C_PCA953X_WIDTH
29 struct pca953x_chip_ngpio {
30 	uint8_t chip;
31 	uint8_t ngpio;
32 };
33 
34 static struct pca953x_chip_ngpio pca953x_chip_ngpios[] =
35     CONFIG_SYS_I2C_PCA953X_WIDTH;
36 
37 /*
38  * Determine the number of GPIO pins supported. If we don't know we assume
39  * 8 pins.
40  */
pca953x_ngpio(uint8_t chip)41 static int pca953x_ngpio(uint8_t chip)
42 {
43 	int i;
44 
45 	for (i = 0; i < ARRAY_SIZE(pca953x_chip_ngpios); i++)
46 		if (pca953x_chip_ngpios[i].chip == chip)
47 			return pca953x_chip_ngpios[i].ngpio;
48 
49 	return 8;
50 }
51 #else
pca953x_ngpio(uint8_t chip)52 static int pca953x_ngpio(uint8_t chip)
53 {
54 	return 8;
55 }
56 #endif
57 
58 /*
59  * Modify masked bits in register
60  */
pca953x_reg_write(uint8_t chip,uint addr,uint mask,uint data)61 static int pca953x_reg_write(uint8_t chip, uint addr, uint mask, uint data)
62 {
63 	uint8_t valb;
64 	uint16_t valw;
65 
66 	if (pca953x_ngpio(chip) <= 8) {
67 		if (i2c_read(chip, addr, 1, &valb, 1))
68 			return -1;
69 
70 		valb &= ~mask;
71 		valb |= data;
72 
73 		return i2c_write(chip, addr, 1, &valb, 1);
74 	} else {
75 		if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2))
76 			return -1;
77 
78 		valw = le16_to_cpu(valw);
79 		valw &= ~mask;
80 		valw |= data;
81 		valw = cpu_to_le16(valw);
82 
83 		return i2c_write(chip, addr << 1, 1, (u8*)&valw, 2);
84 	}
85 }
86 
pca953x_reg_read(uint8_t chip,uint addr,uint * data)87 static int pca953x_reg_read(uint8_t chip, uint addr, uint *data)
88 {
89 	uint8_t valb;
90 	uint16_t valw;
91 
92 	if (pca953x_ngpio(chip) <= 8) {
93 		if (i2c_read(chip, addr, 1, &valb, 1))
94 			return -1;
95 		*data = (int)valb;
96 	} else {
97 		if (i2c_read(chip, addr << 1, 1, (u8*)&valw, 2))
98 			return -1;
99 		*data = (uint)le16_to_cpu(valw);
100 	}
101 	return 0;
102 }
103 
104 /*
105  * Set output value of IO pins in 'mask' to corresponding value in 'data'
106  * 0 = low, 1 = high
107  */
pca953x_set_val(uint8_t chip,uint mask,uint data)108 int pca953x_set_val(uint8_t chip, uint mask, uint data)
109 {
110 	return pca953x_reg_write(chip, PCA953X_OUT, mask, data);
111 }
112 
113 /*
114  * Set read polarity of IO pins in 'mask' to corresponding value in 'data'
115  * 0 = read pin value, 1 = read inverted pin value
116  */
pca953x_set_pol(uint8_t chip,uint mask,uint data)117 int pca953x_set_pol(uint8_t chip, uint mask, uint data)
118 {
119 	return pca953x_reg_write(chip, PCA953X_POL, mask, data);
120 }
121 
122 /*
123  * Set direction of IO pins in 'mask' to corresponding value in 'data'
124  * 0 = output, 1 = input
125  */
pca953x_set_dir(uint8_t chip,uint mask,uint data)126 int pca953x_set_dir(uint8_t chip, uint mask, uint data)
127 {
128 	return pca953x_reg_write(chip, PCA953X_CONF, mask, data);
129 }
130 
131 /*
132  * Read current logic level of all IO pins
133  */
pca953x_get_val(uint8_t chip)134 int pca953x_get_val(uint8_t chip)
135 {
136 	uint val;
137 
138 	if (pca953x_reg_read(chip, PCA953X_IN, &val) < 0)
139 		return -1;
140 
141 	return (int)val;
142 }
143 
144 #if defined(CONFIG_CMD_PCA953X) && !defined(CONFIG_SPL_BUILD)
145 /*
146  * Display pca953x information
147  */
pca953x_info(uint8_t chip)148 static int pca953x_info(uint8_t chip)
149 {
150 	int i;
151 	uint data;
152 	int nr_gpio = pca953x_ngpio(chip);
153 	int msb = nr_gpio - 1;
154 
155 	printf("pca953x@ 0x%x (%d pins):\n\n", chip, nr_gpio);
156 	printf("gpio pins: ");
157 	for (i = msb; i >= 0; i--)
158 		printf("%x", i);
159 	printf("\n");
160 	for (i = 11 + nr_gpio; i > 0; i--)
161 		printf("-");
162 	printf("\n");
163 
164 	if (pca953x_reg_read(chip, PCA953X_CONF, &data) < 0)
165 		return -1;
166 	printf("conf:      ");
167 	for (i = msb; i >= 0; i--)
168 		printf("%c", data & (1 << i) ? 'i' : 'o');
169 	printf("\n");
170 
171 	if (pca953x_reg_read(chip, PCA953X_POL, &data) < 0)
172 		return -1;
173 	printf("invert:    ");
174 	for (i = msb; i >= 0; i--)
175 		printf("%c", data & (1 << i) ? '1' : '0');
176 	printf("\n");
177 
178 	if (pca953x_reg_read(chip, PCA953X_IN, &data) < 0)
179 		return -1;
180 	printf("input:     ");
181 	for (i = msb; i >= 0; i--)
182 		printf("%c", data & (1 << i) ? '1' : '0');
183 	printf("\n");
184 
185 	if (pca953x_reg_read(chip, PCA953X_OUT, &data) < 0)
186 		return -1;
187 	printf("output:    ");
188 	for (i = msb; i >= 0; i--)
189 		printf("%c", data & (1 << i) ? '1' : '0');
190 	printf("\n");
191 
192 	return 0;
193 }
194 
195 static cmd_tbl_t cmd_pca953x[] = {
196 	U_BOOT_CMD_MKENT(device, 3, 0, (void *)PCA953X_CMD_DEVICE, "", ""),
197 	U_BOOT_CMD_MKENT(output, 4, 0, (void *)PCA953X_CMD_OUTPUT, "", ""),
198 	U_BOOT_CMD_MKENT(input, 3, 0, (void *)PCA953X_CMD_INPUT, "", ""),
199 	U_BOOT_CMD_MKENT(invert, 4, 0, (void *)PCA953X_CMD_INVERT, "", ""),
200 	U_BOOT_CMD_MKENT(info, 2, 0, (void *)PCA953X_CMD_INFO, "", ""),
201 };
202 
do_pca953x(cmd_tbl_t * cmdtp,int flag,int argc,char * const argv[])203 static int do_pca953x(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
204 {
205 	static uint8_t chip = CONFIG_SYS_I2C_PCA953X_ADDR;
206 	int ret = CMD_RET_USAGE, val;
207 	ulong ul_arg2 = 0;
208 	ulong ul_arg3 = 0;
209 	cmd_tbl_t *c;
210 
211 	c = find_cmd_tbl(argv[1], cmd_pca953x, ARRAY_SIZE(cmd_pca953x));
212 
213 	/* All commands but "device" require 'maxargs' arguments */
214 	if (!c || !((argc == (c->maxargs)) ||
215 		(((long)c->cmd == PCA953X_CMD_DEVICE) &&
216 		 (argc == (c->maxargs - 1))))) {
217 		return CMD_RET_USAGE;
218 	}
219 
220 	/* arg2 used as chip number or pin number */
221 	if (argc > 2)
222 		ul_arg2 = simple_strtoul(argv[2], NULL, 16);
223 
224 	/* arg3 used as pin or invert value */
225 	if (argc > 3)
226 		ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1;
227 
228 	switch ((long)c->cmd) {
229 	case PCA953X_CMD_INFO:
230 		ret = pca953x_info(chip);
231 		if (ret)
232 			ret = CMD_RET_FAILURE;
233 		break;
234 
235 	case PCA953X_CMD_DEVICE:
236 		if (argc == 3)
237 			chip = (uint8_t)ul_arg2;
238 		printf("Current device address: 0x%x\n", chip);
239 		ret = CMD_RET_SUCCESS;
240 		break;
241 
242 	case PCA953X_CMD_INPUT:
243 		ret = pca953x_set_dir(chip, (1 << ul_arg2),
244 				PCA953X_DIR_IN << ul_arg2);
245 		val = (pca953x_get_val(chip) & (1 << ul_arg2)) != 0;
246 
247 		if (ret)
248 			ret = CMD_RET_FAILURE;
249 		else
250 			printf("chip 0x%02x, pin 0x%lx = %d\n", chip, ul_arg2,
251 									val);
252 		break;
253 
254 	case PCA953X_CMD_OUTPUT:
255 		ret = pca953x_set_dir(chip, (1 << ul_arg2),
256 				(PCA953X_DIR_OUT << ul_arg2));
257 		if (!ret)
258 			ret = pca953x_set_val(chip, (1 << ul_arg2),
259 						(ul_arg3 << ul_arg2));
260 		if (ret)
261 			ret = CMD_RET_FAILURE;
262 		break;
263 
264 	case PCA953X_CMD_INVERT:
265 		ret = pca953x_set_pol(chip, (1 << ul_arg2),
266 					(ul_arg3 << ul_arg2));
267 		if (ret)
268 			ret = CMD_RET_FAILURE;
269 		break;
270 	}
271 
272 	if (ret == CMD_RET_FAILURE)
273 		eprintf("Error talking to chip at 0x%x\n", chip);
274 
275 	return ret;
276 }
277 
278 U_BOOT_CMD(
279 	pca953x,	5,	1,	do_pca953x,
280 	"pca953x gpio access",
281 	"device [dev]\n"
282 	"	- show or set current device address\n"
283 	"pca953x info\n"
284 	"	- display info for current chip\n"
285 	"pca953x output pin 0|1\n"
286 	"	- set pin as output and drive low or high\n"
287 	"pca953x invert pin 0|1\n"
288 	"	- disable/enable polarity inversion for reads\n"
289 	"pca953x input pin\n"
290 	"	- set pin as input and read value"
291 );
292 
293 #endif /* CONFIG_CMD_PCA953X */
294