1// SPDX-License-Identifier: GPL-2.0
2//
3// Register map access API - SPMI support
4//
5// Copyright (c) 2012-2013, The Linux Foundation. All rights reserved.
6//
7// Based on regmap-i2c.c:
8// Copyright 2011 Wolfson Microelectronics plc
9// Author: Mark Brown <broonie@opensource.wolfsonmicro.com>
10
11#include <linux/regmap.h>
12#include <linux/spmi.h>
13#include <linux/module.h>
14#include <linux/init.h>
15
16static int regmap_spmi_base_read(void *context,
17				 const void *reg, size_t reg_size,
18				 void *val, size_t val_size)
19{
20	u8 addr = *(u8 *)reg;
21	int err = 0;
22
23	BUG_ON(reg_size != 1);
24
25	while (val_size-- && !err)
26		err = spmi_register_read(context, addr++, val++);
27
28	return err;
29}
30
31static int regmap_spmi_base_gather_write(void *context,
32					 const void *reg, size_t reg_size,
33					 const void *val, size_t val_size)
34{
35	const u8 *data = val;
36	u8 addr = *(u8 *)reg;
37	int err = 0;
38
39	BUG_ON(reg_size != 1);
40
41	/*
42	 * SPMI defines a more bandwidth-efficient 'Register 0 Write' sequence,
43	 * use it when possible.
44	 */
45	if (addr == 0 && val_size) {
46		err = spmi_register_zero_write(context, *data);
47		if (err)
48			goto err_out;
49
50		data++;
51		addr++;
52		val_size--;
53	}
54
55	while (val_size) {
56		err = spmi_register_write(context, addr, *data);
57		if (err)
58			goto err_out;
59
60		data++;
61		addr++;
62		val_size--;
63	}
64
65err_out:
66	return err;
67}
68
69static int regmap_spmi_base_write(void *context, const void *data,
70				  size_t count)
71{
72	BUG_ON(count < 1);
73	return regmap_spmi_base_gather_write(context, data, 1, data + 1,
74					     count - 1);
75}
76
77static const struct regmap_bus regmap_spmi_base = {
78	.read				= regmap_spmi_base_read,
79	.write				= regmap_spmi_base_write,
80	.gather_write			= regmap_spmi_base_gather_write,
81	.reg_format_endian_default	= REGMAP_ENDIAN_NATIVE,
82	.val_format_endian_default	= REGMAP_ENDIAN_NATIVE,
83};
84
85struct regmap *__regmap_init_spmi_base(struct spmi_device *sdev,
86				       const struct regmap_config *config,
87				       struct lock_class_key *lock_key,
88				       const char *lock_name)
89{
90	return __regmap_init(&sdev->dev, &regmap_spmi_base, sdev, config,
91			     lock_key, lock_name);
92}
93EXPORT_SYMBOL_GPL(__regmap_init_spmi_base);
94
95struct regmap *__devm_regmap_init_spmi_base(struct spmi_device *sdev,
96					    const struct regmap_config *config,
97					    struct lock_class_key *lock_key,
98					    const char *lock_name)
99{
100	return __devm_regmap_init(&sdev->dev, &regmap_spmi_base, sdev, config,
101				  lock_key, lock_name);
102}
103EXPORT_SYMBOL_GPL(__devm_regmap_init_spmi_base);
104
105static int regmap_spmi_ext_read(void *context,
106				const void *reg, size_t reg_size,
107				void *val, size_t val_size)
108{
109	int err = 0;
110	size_t len;
111	u16 addr;
112
113	BUG_ON(reg_size != 2);
114
115	addr = *(u16 *)reg;
116
117	/*
118	 * Split accesses into two to take advantage of the more
119	 * bandwidth-efficient 'Extended Register Read' command when possible
120	 */
121	while (addr <= 0xFF && val_size) {
122		len = min_t(size_t, val_size, 16);
123
124		err = spmi_ext_register_read(context, addr, val, len);
125		if (err)
126			goto err_out;
127
128		addr += len;
129		val += len;
130		val_size -= len;
131	}
132
133	while (val_size) {
134		len = min_t(size_t, val_size, 8);
135
136		err = spmi_ext_register_readl(context, addr, val, len);
137		if (err)
138			goto err_out;
139
140		addr += len;
141		val += len;
142		val_size -= len;
143	}
144
145err_out:
146	return err;
147}
148
149static int regmap_spmi_ext_gather_write(void *context,
150					const void *reg, size_t reg_size,
151					const void *val, size_t val_size)
152{
153	int err = 0;
154	size_t len;
155	u16 addr;
156
157	BUG_ON(reg_size != 2);
158
159	addr = *(u16 *)reg;
160
161	while (addr <= 0xFF && val_size) {
162		len = min_t(size_t, val_size, 16);
163
164		err = spmi_ext_register_write(context, addr, val, len);
165		if (err)
166			goto err_out;
167
168		addr += len;
169		val += len;
170		val_size -= len;
171	}
172
173	while (val_size) {
174		len = min_t(size_t, val_size, 8);
175
176		err = spmi_ext_register_writel(context, addr, val, len);
177		if (err)
178			goto err_out;
179
180		addr += len;
181		val += len;
182		val_size -= len;
183	}
184
185err_out:
186	return err;
187}
188
189static int regmap_spmi_ext_write(void *context, const void *data,
190				 size_t count)
191{
192	BUG_ON(count < 2);
193	return regmap_spmi_ext_gather_write(context, data, 2, data + 2,
194					    count - 2);
195}
196
197static const struct regmap_bus regmap_spmi_ext = {
198	.read				= regmap_spmi_ext_read,
199	.write				= regmap_spmi_ext_write,
200	.gather_write			= regmap_spmi_ext_gather_write,
201	.reg_format_endian_default	= REGMAP_ENDIAN_NATIVE,
202	.val_format_endian_default	= REGMAP_ENDIAN_NATIVE,
203};
204
205struct regmap *__regmap_init_spmi_ext(struct spmi_device *sdev,
206				      const struct regmap_config *config,
207				      struct lock_class_key *lock_key,
208				      const char *lock_name)
209{
210	return __regmap_init(&sdev->dev, &regmap_spmi_ext, sdev, config,
211			     lock_key, lock_name);
212}
213EXPORT_SYMBOL_GPL(__regmap_init_spmi_ext);
214
215struct regmap *__devm_regmap_init_spmi_ext(struct spmi_device *sdev,
216					   const struct regmap_config *config,
217					   struct lock_class_key *lock_key,
218					   const char *lock_name)
219{
220	return __devm_regmap_init(&sdev->dev, &regmap_spmi_ext, sdev, config,
221				  lock_key, lock_name);
222}
223EXPORT_SYMBOL_GPL(__devm_regmap_init_spmi_ext);
224
225MODULE_LICENSE("GPL");
226