1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2020 TOSHIBA CORPORATION
4  * Copyright (c) 2020 Toshiba Electronic Devices & Storage Corporation
5  * Copyright (c) 2020 Nobuhiro Iwamatsu <nobuhiro1.iwamatsu@toshiba.co.jp>
6  */
7 
8 #include <linux/init.h>
9 #include <linux/of.h>
10 #include <linux/io.h>
11 #include <linux/platform_device.h>
12 #include <linux/pinctrl/pinctrl.h>
13 #include <linux/pinctrl/pinmux.h>
14 #include <linux/pinctrl/pinconf.h>
15 #include <linux/pinctrl/pinconf-generic.h>
16 #include "pinctrl-common.h"
17 #include "../core.h"
18 #include "../pinconf.h"
19 #include "../pinctrl-utils.h"
20 
21 #define DSEL_MASK GENMASK(3, 0)
22 
23 /* private data */
24 struct visconti_pinctrl {
25 	void __iomem *base;
26 	struct device *dev;
27 	struct pinctrl_dev *pctl;
28 	struct pinctrl_desc pctl_desc;
29 
30 	const struct visconti_pinctrl_devdata  *devdata;
31 
32 	spinlock_t lock; /* protect pinctrl register */
33 };
34 
35 /* pinconf */
36 static int visconti_pin_config_set(struct pinctrl_dev *pctldev,
37 				  unsigned int _pin,
38 				  unsigned long *configs,
39 				  unsigned int num_configs)
40 {
41 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
42 	const struct visconti_desc_pin *pin = &priv->devdata->pins[_pin];
43 	enum pin_config_param param;
44 	unsigned int arg;
45 	int i, ret = 0;
46 	unsigned int val, set_val, pude_val;
47 	unsigned long flags;
48 
49 	dev_dbg(priv->dev, "%s: pin = %d (%s)\n", __func__, _pin, pin->pin.name);
50 
51 	spin_lock_irqsave(&priv->lock, flags);
52 
53 	for (i = 0; i < num_configs; i++) {
54 		set_val = 0;
55 		pude_val = 0;
56 
57 		param = pinconf_to_config_param(configs[i]);
58 		switch (param) {
59 		case PIN_CONFIG_BIAS_PULL_UP:
60 			set_val = 1;
61 			fallthrough;
62 		case PIN_CONFIG_BIAS_PULL_DOWN:
63 			/* update pudsel setting */
64 			val = readl(priv->base + pin->pudsel_offset);
65 			val &= ~BIT(pin->pud_shift);
66 			val |= set_val << pin->pud_shift;
67 			writel(val, priv->base + pin->pudsel_offset);
68 			pude_val = 1;
69 			fallthrough;
70 		case PIN_CONFIG_BIAS_DISABLE:
71 			/* update pude setting */
72 			val = readl(priv->base + pin->pude_offset);
73 			val &= ~BIT(pin->pud_shift);
74 			val |= pude_val << pin->pud_shift;
75 			writel(val, priv->base + pin->pude_offset);
76 			dev_dbg(priv->dev, "BIAS(%d): off = 0x%x val = 0x%x\n",
77 				param, pin->pude_offset, val);
78 			break;
79 
80 		case PIN_CONFIG_DRIVE_STRENGTH:
81 			arg = pinconf_to_config_argument(configs[i]);
82 			dev_dbg(priv->dev, "DRV_STR arg = %d\n", arg);
83 			switch (arg) {
84 			case 2:
85 			case 4:
86 			case 8:
87 			case 16:
88 			case 24:
89 			case 32:
90 				/*
91 				 * I/O drive capacity setting:
92 				 * 2mA: 0
93 				 * 4mA: 1
94 				 * 8mA: 3
95 				 * 16mA: 7
96 				 * 24mA: 11
97 				 * 32mA: 15
98 				 */
99 				set_val = DIV_ROUND_CLOSEST(arg, 2) - 1;
100 				break;
101 			default:
102 				ret = -EINVAL;
103 				goto err;
104 			}
105 			/* update drive setting */
106 			val = readl(priv->base + pin->dsel_offset);
107 			val &= ~(DSEL_MASK << pin->dsel_shift);
108 			val |= set_val << pin->dsel_shift;
109 			writel(val, priv->base + pin->dsel_offset);
110 			break;
111 
112 		default:
113 			ret = -EOPNOTSUPP;
114 			goto err;
115 		}
116 	}
117 err:
118 	spin_unlock_irqrestore(&priv->lock, flags);
119 	return ret;
120 }
121 
122 static int visconti_pin_config_group_set(struct pinctrl_dev *pctldev,
123 					unsigned int selector,
124 					unsigned long *configs,
125 					unsigned int num_configs)
126 {
127 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
128 	const unsigned int *pins;
129 	unsigned int num_pins;
130 	int i, ret;
131 
132 	pins = priv->devdata->groups[selector].pins;
133 	num_pins = priv->devdata->groups[selector].nr_pins;
134 
135 	dev_dbg(priv->dev, "%s: select = %d, n_pin = %d, n_config = %d\n",
136 		__func__, selector, num_pins, num_configs);
137 
138 	for (i = 0; i < num_pins; i++) {
139 		ret = visconti_pin_config_set(pctldev, pins[i],
140 					     configs, num_configs);
141 		if (ret)
142 			return ret;
143 	}
144 
145 	return 0;
146 }
147 static const struct pinconf_ops visconti_pinconf_ops = {
148 	.is_generic			= true,
149 	.pin_config_set			= visconti_pin_config_set,
150 	.pin_config_group_set		= visconti_pin_config_group_set,
151 	.pin_config_config_dbg_show	= pinconf_generic_dump_config,
152 };
153 
154 /* pinctrl */
155 static int visconti_get_groups_count(struct pinctrl_dev *pctldev)
156 {
157 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
158 
159 	return priv->devdata->nr_groups;
160 }
161 
162 static const char *visconti_get_group_name(struct pinctrl_dev *pctldev,
163 					      unsigned int selector)
164 {
165 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
166 
167 	return priv->devdata->groups[selector].name;
168 }
169 
170 static int visconti_get_group_pins(struct pinctrl_dev *pctldev,
171 				      unsigned int selector,
172 				      const unsigned int **pins,
173 				      unsigned int *num_pins)
174 {
175 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
176 
177 	*pins = priv->devdata->groups[selector].pins;
178 	*num_pins = priv->devdata->groups[selector].nr_pins;
179 
180 	return 0;
181 }
182 
183 static const struct pinctrl_ops visconti_pinctrl_ops = {
184 	.get_groups_count	= visconti_get_groups_count,
185 	.get_group_name		= visconti_get_group_name,
186 	.get_group_pins		= visconti_get_group_pins,
187 	.dt_node_to_map		= pinconf_generic_dt_node_to_map_group,
188 	.dt_free_map		= pinctrl_utils_free_map,
189 };
190 
191 /* pinmux */
192 static int visconti_get_functions_count(struct pinctrl_dev *pctldev)
193 {
194 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
195 
196 	return priv->devdata->nr_functions;
197 }
198 
199 static const char *visconti_get_function_name(struct pinctrl_dev *pctldev,
200 					     unsigned int selector)
201 {
202 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
203 
204 	return priv->devdata->functions[selector].name;
205 }
206 
207 static int visconti_get_function_groups(struct pinctrl_dev *pctldev,
208 				       unsigned int selector,
209 				       const char * const **groups,
210 				       unsigned * const num_groups)
211 {
212 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
213 
214 	*groups = priv->devdata->functions[selector].groups;
215 	*num_groups = priv->devdata->functions[selector].nr_groups;
216 
217 	return 0;
218 }
219 
220 static int visconti_set_mux(struct pinctrl_dev *pctldev,
221 			   unsigned int function, unsigned int group)
222 {
223 	struct visconti_pinctrl *priv = pinctrl_dev_get_drvdata(pctldev);
224 	const struct visconti_pin_function *func = &priv->devdata->functions[function];
225 	const struct visconti_pin_group *grp = &priv->devdata->groups[group];
226 	const struct visconti_mux *mux = &grp->mux;
227 	unsigned int val;
228 	unsigned long flags;
229 
230 	dev_dbg(priv->dev, "%s: function = %d(%s) group = %d(%s)\n", __func__,
231 		function, func->name, group, grp->name);
232 
233 	spin_lock_irqsave(&priv->lock, flags);
234 
235 	/* update mux */
236 	val = readl(priv->base + mux->offset);
237 	val &= ~mux->mask;
238 	val |= mux->val;
239 	writel(val, priv->base + mux->offset);
240 
241 	spin_unlock_irqrestore(&priv->lock, flags);
242 
243 	dev_dbg(priv->dev, "[%x]: 0x%x\n", mux->offset, val);
244 
245 	return 0;
246 }
247 
248 static const struct pinmux_ops visconti_pinmux_ops = {
249 	.get_functions_count	= visconti_get_functions_count,
250 	.get_function_name	= visconti_get_function_name,
251 	.get_function_groups	= visconti_get_function_groups,
252 	.set_mux		= visconti_set_mux,
253 	.strict			= true,
254 };
255 
256 int visconti_pinctrl_probe(struct platform_device *pdev,
257 			  const struct visconti_pinctrl_devdata *devdata)
258 {
259 	struct device *dev = &pdev->dev;
260 	struct visconti_pinctrl *priv;
261 	struct pinctrl_pin_desc *pins;
262 	int i, ret;
263 
264 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
265 	if (!priv)
266 		return -ENOMEM;
267 
268 	priv->dev = dev;
269 	priv->devdata = devdata;
270 	spin_lock_init(&priv->lock);
271 
272 	priv->base = devm_platform_ioremap_resource(pdev, 0);
273 	if (IS_ERR(priv->base)) {
274 		dev_err(dev, "unable to map I/O space\n");
275 		return PTR_ERR(priv->base);
276 	}
277 
278 	pins = devm_kcalloc(dev, devdata->nr_pins,
279 			    sizeof(*pins), GFP_KERNEL);
280 	if (!pins)
281 		return -ENOMEM;
282 
283 	for (i = 0; i < devdata->nr_pins; i++)
284 		pins[i] = devdata->pins[i].pin;
285 
286 	priv->pctl_desc.name = dev_name(dev);
287 	priv->pctl_desc.owner = THIS_MODULE;
288 	priv->pctl_desc.pins = pins;
289 	priv->pctl_desc.npins = devdata->nr_pins;
290 	priv->pctl_desc.confops = &visconti_pinconf_ops;
291 	priv->pctl_desc.pctlops = &visconti_pinctrl_ops;
292 	priv->pctl_desc.pmxops = &visconti_pinmux_ops;
293 
294 	ret = devm_pinctrl_register_and_init(dev, &priv->pctl_desc,
295 					     priv, &priv->pctl);
296 	if (ret) {
297 		dev_err(dev, "couldn't register pinctrl: %d\n", ret);
298 		return ret;
299 	}
300 
301 	if (devdata->unlock)
302 		devdata->unlock(priv->base);
303 
304 	return pinctrl_enable(priv->pctl);
305 }
306