1// SPDX-License-Identifier: GPL-2.0-only
  2/*
  3 * drivers/mfd/si476x-prop.c -- Subroutines to access
  4 * properties of si476x chips
  5 *
  6 * Copyright (C) 2012 Innovative Converged Devices(ICD)
  7 * Copyright (C) 2013 Andrey Smirnov
  8 *
  9 * Author: Andrey Smirnov <andrew.smirnov@gmail.com>
 10 */
 11#include <linux/module.h>
 12
 13#include <linux/mfd/si476x-core.h>
 14
 15struct si476x_property_range {
 16	u16 low, high;
 17};
 18
 19static bool si476x_core_element_is_in_array(u16 element,
 20					    const u16 array[],
 21					    size_t size)
 22{
 23	int i;
 24
 25	for (i = 0; i < size; i++)
 26		if (element == array[i])
 27			return true;
 28
 29	return false;
 30}
 31
 32static bool si476x_core_element_is_in_range(u16 element,
 33					    const struct si476x_property_range range[],
 34					    size_t size)
 35{
 36	int i;
 37
 38	for (i = 0; i < size; i++)
 39		if (element <= range[i].high && element >= range[i].low)
 40			return true;
 41
 42	return false;
 43}
 44
 45static bool si476x_core_is_valid_property_a10(struct si476x_core *core,
 46					      u16 property)
 47{
 48	static const u16 valid_properties[] = {
 49		0x0000,
 50		0x0500, 0x0501,
 51		0x0600,
 52		0x0709, 0x070C, 0x070D, 0x70E, 0x710,
 53		0x0718,
 54		0x1207, 0x1208,
 55		0x2007,
 56		0x2300,
 57	};
 58
 59	static const struct si476x_property_range valid_ranges[] = {
 60		{ 0x0200, 0x0203 },
 61		{ 0x0300, 0x0303 },
 62		{ 0x0400, 0x0404 },
 63		{ 0x0700, 0x0707 },
 64		{ 0x1100, 0x1102 },
 65		{ 0x1200, 0x1204 },
 66		{ 0x1300, 0x1306 },
 67		{ 0x2000, 0x2005 },
 68		{ 0x2100, 0x2104 },
 69		{ 0x2106, 0x2106 },
 70		{ 0x2200, 0x220E },
 71		{ 0x3100, 0x3104 },
 72		{ 0x3207, 0x320F },
 73		{ 0x3300, 0x3304 },
 74		{ 0x3500, 0x3517 },
 75		{ 0x3600, 0x3617 },
 76		{ 0x3700, 0x3717 },
 77		{ 0x4000, 0x4003 },
 78	};
 79
 80	return	si476x_core_element_is_in_range(property, valid_ranges,
 81						ARRAY_SIZE(valid_ranges)) ||
 82		si476x_core_element_is_in_array(property, valid_properties,
 83						ARRAY_SIZE(valid_properties));
 84}
 85
 86static bool si476x_core_is_valid_property_a20(struct si476x_core *core,
 87					      u16 property)
 88{
 89	static const u16 valid_properties[] = {
 90		0x071B,
 91		0x1006,
 92		0x2210,
 93		0x3401,
 94	};
 95
 96	static const struct si476x_property_range valid_ranges[] = {
 97		{ 0x2215, 0x2219 },
 98	};
 99
100	return	si476x_core_is_valid_property_a10(core, property) ||
101		si476x_core_element_is_in_range(property, valid_ranges,
102						ARRAY_SIZE(valid_ranges))  ||
103		si476x_core_element_is_in_array(property, valid_properties,
104						ARRAY_SIZE(valid_properties));
105}
106
107static bool si476x_core_is_valid_property_a30(struct si476x_core *core,
108					      u16 property)
109{
110	static const u16 valid_properties[] = {
111		0x071C, 0x071D,
112		0x1007, 0x1008,
113		0x220F, 0x2214,
114		0x2301,
115		0x3105, 0x3106,
116		0x3402,
117	};
118
119	static const struct si476x_property_range valid_ranges[] = {
120		{ 0x0405, 0x0411 },
121		{ 0x2008, 0x200B },
122		{ 0x2220, 0x2223 },
123		{ 0x3100, 0x3106 },
124	};
125
126	return	si476x_core_is_valid_property_a20(core, property) ||
127		si476x_core_element_is_in_range(property, valid_ranges,
128						ARRAY_SIZE(valid_ranges)) ||
129		si476x_core_element_is_in_array(property, valid_properties,
130						ARRAY_SIZE(valid_properties));
131}
132
133typedef bool (*valid_property_pred_t) (struct si476x_core *, u16);
134
135static bool si476x_core_is_valid_property(struct si476x_core *core,
136					  u16 property)
137{
138	static const valid_property_pred_t is_valid_property[] = {
139		[SI476X_REVISION_A10] = si476x_core_is_valid_property_a10,
140		[SI476X_REVISION_A20] = si476x_core_is_valid_property_a20,
141		[SI476X_REVISION_A30] = si476x_core_is_valid_property_a30,
142	};
143
144	BUG_ON(core->revision > SI476X_REVISION_A30 ||
145	       core->revision == -1);
146	return is_valid_property[core->revision](core, property);
147}
148
149
150static bool si476x_core_is_readonly_property(struct si476x_core *core,
151					     u16 property)
152{
153	BUG_ON(core->revision > SI476X_REVISION_A30 ||
154	       core->revision == -1);
155
156	switch (core->revision) {
157	case SI476X_REVISION_A10:
158		return (property == 0x3200);
159	case SI476X_REVISION_A20:
160		return (property == 0x1006 ||
161			property == 0x2210 ||
162			property == 0x3200);
163	case SI476X_REVISION_A30:
164		return false;
165	}
166
167	return false;
168}
169
170static bool si476x_core_regmap_readable_register(struct device *dev,
171						 unsigned int reg)
172{
173	struct i2c_client *client = to_i2c_client(dev);
174	struct si476x_core *core = i2c_get_clientdata(client);
175
176	return si476x_core_is_valid_property(core, (u16) reg);
177
178}
179
180static bool si476x_core_regmap_writable_register(struct device *dev,
181						 unsigned int reg)
182{
183	struct i2c_client *client = to_i2c_client(dev);
184	struct si476x_core *core = i2c_get_clientdata(client);
185
186	return si476x_core_is_valid_property(core, (u16) reg) &&
187		!si476x_core_is_readonly_property(core, (u16) reg);
188}
189
190
191static int si476x_core_regmap_write(void *context, unsigned int reg,
192				    unsigned int val)
193{
194	return si476x_core_cmd_set_property(context, reg, val);
195}
196
197static int si476x_core_regmap_read(void *context, unsigned int reg,
198				   unsigned *val)
199{
200	struct si476x_core *core = context;
201	int err;
202
203	err = si476x_core_cmd_get_property(core, reg);
204	if (err < 0)
205		return err;
206
207	*val = err;
208
209	return 0;
210}
211
212
213static const struct regmap_config si476x_regmap_config = {
214	.reg_bits = 16,
215	.val_bits = 16,
216
217	.max_register = 0x4003,
218
219	.writeable_reg = si476x_core_regmap_writable_register,
220	.readable_reg = si476x_core_regmap_readable_register,
221
222	.reg_read = si476x_core_regmap_read,
223	.reg_write = si476x_core_regmap_write,
224
225	.cache_type = REGCACHE_RBTREE,
226};
227
228struct regmap *devm_regmap_init_si476x(struct si476x_core *core)
229{
230	return devm_regmap_init(&core->client->dev, NULL,
231				core, &si476x_regmap_config);
232}
233EXPORT_SYMBOL_GPL(devm_regmap_init_si476x);