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1d0ea069 | 1 | // SPDX-License-Identifier: GPL-2.0-only |
55b951e7 EM |
2 | /* |
3 | * max1111.c - +2.7V, Low-Power, Multichannel, Serial 8-bit ADCs | |
4 | * | |
5 | * Based on arch/arm/mach-pxa/corgi_ssp.c | |
6 | * | |
7 | * Copyright (C) 2004-2005 Richard Purdie | |
8 | * | |
9 | * Copyright (C) 2008 Marvell International Ltd. | |
91c8eabe | 10 | * Eric Miao <eric.miao@marvell.com> |
55b951e7 EM |
11 | */ |
12 | ||
13 | #include <linux/module.h> | |
14 | #include <linux/kernel.h> | |
15 | #include <linux/init.h> | |
16 | #include <linux/err.h> | |
17 | #include <linux/hwmon.h> | |
18 | #include <linux/hwmon-sysfs.h> | |
19 | #include <linux/spi/spi.h> | |
5a0e3ad6 | 20 | #include <linux/slab.h> |
55b951e7 | 21 | |
9224c38a GR |
22 | enum chips { max1110, max1111, max1112, max1113 }; |
23 | ||
55b951e7 EM |
24 | #define MAX1111_TX_BUF_SIZE 1 |
25 | #define MAX1111_RX_BUF_SIZE 2 | |
26 | ||
27 | /* MAX1111 Commands */ | |
28 | #define MAX1111_CTRL_PD0 (1u << 0) | |
29 | #define MAX1111_CTRL_PD1 (1u << 1) | |
30 | #define MAX1111_CTRL_SGL (1u << 2) | |
31 | #define MAX1111_CTRL_UNI (1u << 3) | |
9224c38a | 32 | #define MAX1110_CTRL_SEL_SH (4) |
55b951e7 EM |
33 | #define MAX1111_CTRL_SEL_SH (5) /* NOTE: bit 4 is ignored */ |
34 | #define MAX1111_CTRL_STR (1u << 7) | |
35 | ||
36 | struct max1111_data { | |
37 | struct spi_device *spi; | |
38 | struct device *hwmon_dev; | |
39 | struct spi_message msg; | |
40 | struct spi_transfer xfer[2]; | |
d737c09c JD |
41 | uint8_t tx_buf[MAX1111_TX_BUF_SIZE]; |
42 | uint8_t rx_buf[MAX1111_RX_BUF_SIZE]; | |
d3f684f2 PH |
43 | struct mutex drvdata_lock; |
44 | /* protect msg, xfer and buffers from multiple access */ | |
9224c38a GR |
45 | int sel_sh; |
46 | int lsb; | |
55b951e7 EM |
47 | }; |
48 | ||
49 | static int max1111_read(struct device *dev, int channel) | |
50 | { | |
51 | struct max1111_data *data = dev_get_drvdata(dev); | |
52 | uint8_t v1, v2; | |
53 | int err; | |
54 | ||
d3f684f2 PH |
55 | /* writing to drvdata struct is not thread safe, wait on mutex */ |
56 | mutex_lock(&data->drvdata_lock); | |
57 | ||
9224c38a | 58 | data->tx_buf[0] = (channel << data->sel_sh) | |
55b951e7 EM |
59 | MAX1111_CTRL_PD0 | MAX1111_CTRL_PD1 | |
60 | MAX1111_CTRL_SGL | MAX1111_CTRL_UNI | MAX1111_CTRL_STR; | |
61 | ||
62 | err = spi_sync(data->spi, &data->msg); | |
63 | if (err < 0) { | |
64 | dev_err(dev, "spi_sync failed with %d\n", err); | |
d3f684f2 | 65 | mutex_unlock(&data->drvdata_lock); |
55b951e7 EM |
66 | return err; |
67 | } | |
68 | ||
69 | v1 = data->rx_buf[0]; | |
70 | v2 = data->rx_buf[1]; | |
71 | ||
d3f684f2 PH |
72 | mutex_unlock(&data->drvdata_lock); |
73 | ||
55b951e7 EM |
74 | if ((v1 & 0xc0) || (v2 & 0x3f)) |
75 | return -EINVAL; | |
76 | ||
77 | return (v1 << 2) | (v2 >> 6); | |
78 | } | |
79 | ||
f16177c2 EM |
80 | #ifdef CONFIG_SHARPSL_PM |
81 | static struct max1111_data *the_max1111; | |
82 | ||
a9ae9c52 | 83 | int max1111_read_channel(int channel); |
f16177c2 EM |
84 | int max1111_read_channel(int channel) |
85 | { | |
3c2e2266 GR |
86 | if (!the_max1111 || !the_max1111->spi) |
87 | return -ENODEV; | |
88 | ||
f16177c2 EM |
89 | return max1111_read(&the_max1111->spi->dev, channel); |
90 | } | |
91 | EXPORT_SYMBOL(max1111_read_channel); | |
92 | #endif | |
93 | ||
55b951e7 EM |
94 | /* |
95 | * NOTE: SPI devices do not have a default 'name' attribute, which is | |
96 | * likely to be used by hwmon applications to distinguish between | |
97 | * different devices, explicitly add a name attribute here. | |
98 | */ | |
17c45c4d | 99 | static ssize_t name_show(struct device *dev, |
55b951e7 EM |
100 | struct device_attribute *attr, char *buf) |
101 | { | |
9224c38a | 102 | return sprintf(buf, "%s\n", to_spi_device(dev)->modalias); |
55b951e7 EM |
103 | } |
104 | ||
105 | static ssize_t show_adc(struct device *dev, | |
106 | struct device_attribute *attr, char *buf) | |
107 | { | |
9224c38a | 108 | struct max1111_data *data = dev_get_drvdata(dev); |
55b951e7 EM |
109 | int channel = to_sensor_dev_attr(attr)->index; |
110 | int ret; | |
111 | ||
112 | ret = max1111_read(dev, channel); | |
113 | if (ret < 0) | |
114 | return ret; | |
115 | ||
51683ee8 | 116 | /* |
9224c38a GR |
117 | * Assume the reference voltage to be 2.048V or 4.096V, with an 8-bit |
118 | * sample. The LSB weight is 8mV or 16mV depending on the chip type. | |
012f3b91 | 119 | */ |
9224c38a | 120 | return sprintf(buf, "%d\n", ret * data->lsb); |
55b951e7 EM |
121 | } |
122 | ||
123 | #define MAX1111_ADC_ATTR(_id) \ | |
012f3b91 | 124 | SENSOR_DEVICE_ATTR(in##_id##_input, S_IRUGO, show_adc, NULL, _id) |
55b951e7 | 125 | |
17c45c4d | 126 | static DEVICE_ATTR_RO(name); |
55b951e7 EM |
127 | static MAX1111_ADC_ATTR(0); |
128 | static MAX1111_ADC_ATTR(1); | |
129 | static MAX1111_ADC_ATTR(2); | |
130 | static MAX1111_ADC_ATTR(3); | |
9224c38a GR |
131 | static MAX1111_ADC_ATTR(4); |
132 | static MAX1111_ADC_ATTR(5); | |
133 | static MAX1111_ADC_ATTR(6); | |
134 | static MAX1111_ADC_ATTR(7); | |
55b951e7 EM |
135 | |
136 | static struct attribute *max1111_attributes[] = { | |
137 | &dev_attr_name.attr, | |
012f3b91 EM |
138 | &sensor_dev_attr_in0_input.dev_attr.attr, |
139 | &sensor_dev_attr_in1_input.dev_attr.attr, | |
140 | &sensor_dev_attr_in2_input.dev_attr.attr, | |
141 | &sensor_dev_attr_in3_input.dev_attr.attr, | |
55b951e7 EM |
142 | NULL, |
143 | }; | |
144 | ||
145 | static const struct attribute_group max1111_attr_group = { | |
146 | .attrs = max1111_attributes, | |
147 | }; | |
148 | ||
9224c38a GR |
149 | static struct attribute *max1110_attributes[] = { |
150 | &sensor_dev_attr_in4_input.dev_attr.attr, | |
151 | &sensor_dev_attr_in5_input.dev_attr.attr, | |
152 | &sensor_dev_attr_in6_input.dev_attr.attr, | |
153 | &sensor_dev_attr_in7_input.dev_attr.attr, | |
154 | NULL, | |
155 | }; | |
156 | ||
157 | static const struct attribute_group max1110_attr_group = { | |
158 | .attrs = max1110_attributes, | |
159 | }; | |
160 | ||
6c931ae1 | 161 | static int setup_transfer(struct max1111_data *data) |
55b951e7 EM |
162 | { |
163 | struct spi_message *m; | |
164 | struct spi_transfer *x; | |
165 | ||
55b951e7 EM |
166 | m = &data->msg; |
167 | x = &data->xfer[0]; | |
168 | ||
169 | spi_message_init(m); | |
170 | ||
171 | x->tx_buf = &data->tx_buf[0]; | |
d737c09c | 172 | x->len = MAX1111_TX_BUF_SIZE; |
55b951e7 EM |
173 | spi_message_add_tail(x, m); |
174 | ||
175 | x++; | |
176 | x->rx_buf = &data->rx_buf[0]; | |
d737c09c | 177 | x->len = MAX1111_RX_BUF_SIZE; |
55b951e7 EM |
178 | spi_message_add_tail(x, m); |
179 | ||
180 | return 0; | |
181 | } | |
182 | ||
6c931ae1 | 183 | static int max1111_probe(struct spi_device *spi) |
55b951e7 | 184 | { |
9224c38a | 185 | enum chips chip = spi_get_device_id(spi)->driver_data; |
55b951e7 EM |
186 | struct max1111_data *data; |
187 | int err; | |
188 | ||
189 | spi->bits_per_word = 8; | |
190 | spi->mode = SPI_MODE_0; | |
191 | err = spi_setup(spi); | |
192 | if (err < 0) | |
193 | return err; | |
194 | ||
661f020f | 195 | data = devm_kzalloc(&spi->dev, sizeof(struct max1111_data), GFP_KERNEL); |
611cd8ae | 196 | if (data == NULL) |
55b951e7 | 197 | return -ENOMEM; |
55b951e7 | 198 | |
9224c38a GR |
199 | switch (chip) { |
200 | case max1110: | |
201 | data->lsb = 8; | |
202 | data->sel_sh = MAX1110_CTRL_SEL_SH; | |
203 | break; | |
204 | case max1111: | |
205 | data->lsb = 8; | |
206 | data->sel_sh = MAX1111_CTRL_SEL_SH; | |
207 | break; | |
208 | case max1112: | |
209 | data->lsb = 16; | |
210 | data->sel_sh = MAX1110_CTRL_SEL_SH; | |
211 | break; | |
212 | case max1113: | |
213 | data->lsb = 16; | |
214 | data->sel_sh = MAX1111_CTRL_SEL_SH; | |
215 | break; | |
216 | } | |
55b951e7 EM |
217 | err = setup_transfer(data); |
218 | if (err) | |
661f020f | 219 | return err; |
55b951e7 | 220 | |
d3f684f2 PH |
221 | mutex_init(&data->drvdata_lock); |
222 | ||
55b951e7 EM |
223 | data->spi = spi; |
224 | spi_set_drvdata(spi, data); | |
225 | ||
226 | err = sysfs_create_group(&spi->dev.kobj, &max1111_attr_group); | |
227 | if (err) { | |
228 | dev_err(&spi->dev, "failed to create attribute group\n"); | |
661f020f | 229 | return err; |
55b951e7 | 230 | } |
9224c38a GR |
231 | if (chip == max1110 || chip == max1112) { |
232 | err = sysfs_create_group(&spi->dev.kobj, &max1110_attr_group); | |
233 | if (err) { | |
234 | dev_err(&spi->dev, | |
235 | "failed to create extended attribute group\n"); | |
236 | goto err_remove; | |
237 | } | |
238 | } | |
55b951e7 EM |
239 | |
240 | data->hwmon_dev = hwmon_device_register(&spi->dev); | |
241 | if (IS_ERR(data->hwmon_dev)) { | |
242 | dev_err(&spi->dev, "failed to create hwmon device\n"); | |
243 | err = PTR_ERR(data->hwmon_dev); | |
244 | goto err_remove; | |
245 | } | |
246 | ||
f16177c2 EM |
247 | #ifdef CONFIG_SHARPSL_PM |
248 | the_max1111 = data; | |
249 | #endif | |
55b951e7 EM |
250 | return 0; |
251 | ||
252 | err_remove: | |
9224c38a | 253 | sysfs_remove_group(&spi->dev.kobj, &max1110_attr_group); |
55b951e7 | 254 | sysfs_remove_group(&spi->dev.kobj, &max1111_attr_group); |
55b951e7 EM |
255 | return err; |
256 | } | |
257 | ||
a0386bba | 258 | static void max1111_remove(struct spi_device *spi) |
55b951e7 EM |
259 | { |
260 | struct max1111_data *data = spi_get_drvdata(spi); | |
261 | ||
3c2e2266 GR |
262 | #ifdef CONFIG_SHARPSL_PM |
263 | the_max1111 = NULL; | |
264 | #endif | |
55b951e7 | 265 | hwmon_device_unregister(data->hwmon_dev); |
9224c38a | 266 | sysfs_remove_group(&spi->dev.kobj, &max1110_attr_group); |
55b951e7 | 267 | sysfs_remove_group(&spi->dev.kobj, &max1111_attr_group); |
d3f684f2 | 268 | mutex_destroy(&data->drvdata_lock); |
55b951e7 EM |
269 | } |
270 | ||
9224c38a GR |
271 | static const struct spi_device_id max1111_ids[] = { |
272 | { "max1110", max1110 }, | |
273 | { "max1111", max1111 }, | |
274 | { "max1112", max1112 }, | |
275 | { "max1113", max1113 }, | |
276 | { }, | |
277 | }; | |
278 | MODULE_DEVICE_TABLE(spi, max1111_ids); | |
279 | ||
55b951e7 EM |
280 | static struct spi_driver max1111_driver = { |
281 | .driver = { | |
282 | .name = "max1111", | |
55b951e7 | 283 | }, |
9224c38a | 284 | .id_table = max1111_ids, |
55b951e7 | 285 | .probe = max1111_probe, |
9e5e9b7a | 286 | .remove = max1111_remove, |
55b951e7 EM |
287 | }; |
288 | ||
91efffe2 | 289 | module_spi_driver(max1111_driver); |
55b951e7 EM |
290 | |
291 | MODULE_AUTHOR("Eric Miao <eric.miao@marvell.com>"); | |
9224c38a | 292 | MODULE_DESCRIPTION("MAX1110/MAX1111/MAX1112/MAX1113 ADC Driver"); |
55b951e7 | 293 | MODULE_LICENSE("GPL"); |