1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2013 - 2018 Xilinx, Michal Simek
4  */
5 
6 #include <common.h>
7 #include <errno.h>
8 #include <log.h>
9 #include <malloc.h>
10 #include <linux/list.h>
11 #include <asm/io.h>
12 #include <asm/gpio.h>
13 #include <dm.h>
14 #include <dt-bindings/gpio/gpio.h>
15 
16 #define XILINX_GPIO_MAX_BANK	2
17 
18 /* Gpio simple map */
19 struct gpio_regs {
20 	u32 gpiodata;
21 	u32 gpiodir;
22 };
23 
24 struct xilinx_gpio_plat {
25 	struct gpio_regs *regs;
26 	int bank_max[XILINX_GPIO_MAX_BANK];
27 	int bank_input[XILINX_GPIO_MAX_BANK];
28 	int bank_output[XILINX_GPIO_MAX_BANK];
29 	u32 dout_default[XILINX_GPIO_MAX_BANK];
30 };
31 
32 struct xilinx_gpio_privdata {
33 	u32 output_val[XILINX_GPIO_MAX_BANK];
34 };
35 
xilinx_gpio_get_bank_pin(unsigned offset,u32 * bank_num,u32 * bank_pin_num,struct udevice * dev)36 static int xilinx_gpio_get_bank_pin(unsigned offset, u32 *bank_num,
37 				    u32 *bank_pin_num, struct udevice *dev)
38 {
39 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
40 	u32 bank, max_pins;
41 	/* the first gpio is 0 not 1 */
42 	u32 pin_num = offset;
43 
44 	for (bank = 0; bank < XILINX_GPIO_MAX_BANK; bank++) {
45 		max_pins = plat->bank_max[bank];
46 		if (pin_num < max_pins) {
47 			debug("%s: found at bank 0x%x pin 0x%x\n", __func__,
48 			      bank, pin_num);
49 			*bank_num = bank;
50 			*bank_pin_num = pin_num;
51 			return 0;
52 		}
53 		pin_num -= max_pins;
54 	}
55 
56 	return -EINVAL;
57 }
58 
xilinx_gpio_set_value(struct udevice * dev,unsigned offset,int value)59 static int xilinx_gpio_set_value(struct udevice *dev, unsigned offset,
60 				 int value)
61 {
62 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
63 	struct xilinx_gpio_privdata *priv = dev_get_priv(dev);
64 	int val, ret;
65 	u32 bank, pin;
66 
67 	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
68 	if (ret)
69 		return ret;
70 
71 	val = priv->output_val[bank];
72 
73 	debug("%s: regs: %lx, value: %x, gpio: %x, bank %x, pin %x, out %x\n",
74 	      __func__, (ulong)plat->regs, value, offset, bank, pin, val);
75 
76 	if (value)
77 		val = val | (1 << pin);
78 	else
79 		val = val & ~(1 << pin);
80 
81 	writel(val, &plat->regs->gpiodata + bank * 2);
82 
83 	priv->output_val[bank] = val;
84 
85 	return 0;
86 };
87 
xilinx_gpio_get_value(struct udevice * dev,unsigned offset)88 static int xilinx_gpio_get_value(struct udevice *dev, unsigned offset)
89 {
90 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
91 	struct xilinx_gpio_privdata *priv = dev_get_priv(dev);
92 	int val, ret;
93 	u32 bank, pin;
94 
95 	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
96 	if (ret)
97 		return ret;
98 
99 	debug("%s: regs: %lx, gpio: %x, bank %x, pin %x\n", __func__,
100 	      (ulong)plat->regs, offset, bank, pin);
101 
102 	if (plat->bank_output[bank]) {
103 		debug("%s: Read saved output value\n", __func__);
104 		val = priv->output_val[bank];
105 	} else {
106 		debug("%s: Read input value from reg\n", __func__);
107 		val = readl(&plat->regs->gpiodata + bank * 2);
108 	}
109 
110 	val = !!(val & (1 << pin));
111 
112 	return val;
113 };
114 
xilinx_gpio_get_function(struct udevice * dev,unsigned offset)115 static int xilinx_gpio_get_function(struct udevice *dev, unsigned offset)
116 {
117 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
118 	int val, ret;
119 	u32 bank, pin;
120 
121 	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
122 	if (ret)
123 		return ret;
124 
125 	/* Check if all pins are inputs */
126 	if (plat->bank_input[bank])
127 		return GPIOF_INPUT;
128 
129 	/* Check if all pins are outputs */
130 	if (plat->bank_output[bank])
131 		return GPIOF_OUTPUT;
132 
133 	/* FIXME test on dual */
134 	val = readl(&plat->regs->gpiodir + bank * 2);
135 	val = !(val & (1 << pin));
136 
137 	/* input is 1 in reg but GPIOF_INPUT is 0 */
138 	/* output is 0 in reg but GPIOF_OUTPUT is 1 */
139 
140 	return val;
141 }
142 
xilinx_gpio_direction_output(struct udevice * dev,unsigned offset,int value)143 static int xilinx_gpio_direction_output(struct udevice *dev, unsigned offset,
144 					int value)
145 {
146 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
147 	int val, ret;
148 	u32 bank, pin;
149 
150 	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
151 	if (ret)
152 		return ret;
153 
154 	/* can't change it if all is input by default */
155 	if (plat->bank_input[bank])
156 		return -EINVAL;
157 
158 	xilinx_gpio_set_value(dev, offset, value);
159 
160 	if (!plat->bank_output[bank]) {
161 		val = readl(&plat->regs->gpiodir + bank * 2);
162 		val = val & ~(1 << pin);
163 		writel(val, &plat->regs->gpiodir + bank * 2);
164 	}
165 
166 	return 0;
167 }
168 
xilinx_gpio_direction_input(struct udevice * dev,unsigned offset)169 static int xilinx_gpio_direction_input(struct udevice *dev, unsigned offset)
170 {
171 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
172 	int val, ret;
173 	u32 bank, pin;
174 
175 	ret = xilinx_gpio_get_bank_pin(offset, &bank, &pin, dev);
176 	if (ret)
177 		return ret;
178 
179 	/* Already input */
180 	if (plat->bank_input[bank])
181 		return 0;
182 
183 	/* can't change it if all is output by default */
184 	if (plat->bank_output[bank])
185 		return -EINVAL;
186 
187 	val = readl(&plat->regs->gpiodir + bank * 2);
188 	val = val | (1 << pin);
189 	writel(val, &plat->regs->gpiodir + bank * 2);
190 
191 	return 0;
192 }
193 
xilinx_gpio_xlate(struct udevice * dev,struct gpio_desc * desc,struct ofnode_phandle_args * args)194 static int xilinx_gpio_xlate(struct udevice *dev, struct gpio_desc *desc,
195 			     struct ofnode_phandle_args *args)
196 {
197 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
198 
199 	desc->offset = args->args[0];
200 
201 	debug("%s: argc: %x, [0]: %x, [1]: %x, [2]: %x\n", __func__,
202 	      args->args_count, args->args[0], args->args[1], args->args[2]);
203 
204 	/*
205 	 * The second cell is channel offset:
206 	 *  0 is first channel, 8 is second channel
207 	 *
208 	 * U-Boot driver just combine channels together that's why simply
209 	 * add amount of pins in second channel if present.
210 	 */
211 	if (args->args[1]) {
212 		if (!plat->bank_max[1]) {
213 			printf("%s: %s has no second channel\n",
214 			       __func__, dev->name);
215 			return -EINVAL;
216 		}
217 
218 		desc->offset += plat->bank_max[0];
219 	}
220 
221 	/* The third cell is optional */
222 	if (args->args_count > 2)
223 		desc->flags = (args->args[2] &
224 			       GPIO_ACTIVE_LOW ? GPIOD_ACTIVE_LOW : 0);
225 
226 	debug("%s: offset %x, flags %lx\n",
227 	      __func__, desc->offset, desc->flags);
228 	return 0;
229 }
230 
231 static const struct dm_gpio_ops xilinx_gpio_ops = {
232 	.direction_input = xilinx_gpio_direction_input,
233 	.direction_output = xilinx_gpio_direction_output,
234 	.get_value = xilinx_gpio_get_value,
235 	.set_value = xilinx_gpio_set_value,
236 	.get_function = xilinx_gpio_get_function,
237 	.xlate = xilinx_gpio_xlate,
238 };
239 
xilinx_gpio_probe(struct udevice * dev)240 static int xilinx_gpio_probe(struct udevice *dev)
241 {
242 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
243 	struct xilinx_gpio_privdata *priv = dev_get_priv(dev);
244 	struct gpio_dev_priv *uc_priv = dev_get_uclass_priv(dev);
245 	const void *label_ptr;
246 
247 	label_ptr = dev_read_prop(dev, "label", NULL);
248 	if (label_ptr) {
249 		uc_priv->bank_name = strdup(label_ptr);
250 		if (!uc_priv->bank_name)
251 			return -ENOMEM;
252 	} else {
253 		uc_priv->bank_name = dev->name;
254 	}
255 
256 	uc_priv->gpio_count = plat->bank_max[0] + plat->bank_max[1];
257 
258 	priv->output_val[0] = plat->dout_default[0];
259 
260 	if (plat->bank_max[1])
261 		priv->output_val[1] = plat->dout_default[1];
262 
263 	return 0;
264 }
265 
xilinx_gpio_of_to_plat(struct udevice * dev)266 static int xilinx_gpio_of_to_plat(struct udevice *dev)
267 {
268 	struct xilinx_gpio_plat *plat = dev_get_plat(dev);
269 	int is_dual;
270 
271 	plat->regs = (struct gpio_regs *)dev_read_addr(dev);
272 
273 	plat->bank_max[0] = dev_read_u32_default(dev, "xlnx,gpio-width", 0);
274 	plat->bank_input[0] = dev_read_u32_default(dev, "xlnx,all-inputs", 0);
275 	plat->bank_output[0] = dev_read_u32_default(dev, "xlnx,all-outputs", 0);
276 	plat->dout_default[0] = dev_read_u32_default(dev, "xlnx,dout-default",
277 						     0);
278 
279 	is_dual = dev_read_u32_default(dev, "xlnx,is-dual", 0);
280 	if (is_dual) {
281 		plat->bank_max[1] = dev_read_u32_default(dev,
282 							 "xlnx,gpio2-width", 0);
283 		plat->bank_input[1] = dev_read_u32_default(dev,
284 						"xlnx,all-inputs-2", 0);
285 		plat->bank_output[1] = dev_read_u32_default(dev,
286 						"xlnx,all-outputs-2", 0);
287 		plat->dout_default[1] = dev_read_u32_default(dev,
288 						"xlnx,dout-default-2", 0);
289 	}
290 
291 	return 0;
292 }
293 
294 static const struct udevice_id xilinx_gpio_ids[] = {
295 	{ .compatible = "xlnx,xps-gpio-1.00.a",},
296 	{ }
297 };
298 
299 U_BOOT_DRIVER(xilinx_gpio) = {
300 	.name = "xlnx_gpio",
301 	.id = UCLASS_GPIO,
302 	.ops = &xilinx_gpio_ops,
303 	.of_match = xilinx_gpio_ids,
304 	.of_to_plat = xilinx_gpio_of_to_plat,
305 	.probe = xilinx_gpio_probe,
306 	.plat_auto	= sizeof(struct xilinx_gpio_plat),
307 	.priv_auto	= sizeof(struct xilinx_gpio_privdata),
308 };
309