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-rw-r--r--drivers/mfd/Kconfig7
-rw-r--r--drivers/mfd/Makefile3
-rw-r--r--drivers/mfd/pcf50633-adc.c277
3 files changed, 286 insertions, 1 deletions
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index 3ac32e45b03b..2fa3504e165a 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -226,6 +226,13 @@ config MFD_PCF50633
226 facilities, and registers devices for the various functions 226 facilities, and registers devices for the various functions
227 so that function-specific drivers can bind to them. 227 so that function-specific drivers can bind to them.
228 228
229config PCF50633_ADC
230 tristate "Support for NXP PCF50633 ADC"
231 depends on MFD_PCF50633
232 help
233 Say yes here if you want to include support for ADC in the
234 NXP PCF50633 chip.
235
229endmenu 236endmenu
230 237
231menu "Multimedia Capabilities Port drivers" 238menu "Multimedia Capabilities Port drivers"
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 23d4d10981b3..138f9c4d3d7b 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -38,4 +38,5 @@ obj-$(CONFIG_UCB1400_CORE) += ucb1400_core.o
38 38
39obj-$(CONFIG_PMIC_DA903X) += da903x.o 39obj-$(CONFIG_PMIC_DA903X) += da903x.o
40 40
41obj-$(CONFIG_MFD_PCF50633) += pcf50633-core.o \ No newline at end of file 41obj-$(CONFIG_MFD_PCF50633) += pcf50633-core.o
42obj-$(CONFIG_PCF50633_ADC) += pcf50633-adc.o \ No newline at end of file
diff --git a/drivers/mfd/pcf50633-adc.c b/drivers/mfd/pcf50633-adc.c
new file mode 100644
index 000000000000..c2d05becfa97
--- /dev/null
+++ b/drivers/mfd/pcf50633-adc.c
@@ -0,0 +1,277 @@
1/* NXP PCF50633 ADC Driver
2 *
3 * (C) 2006-2008 by Openmoko, Inc.
4 * Author: Balaji Rao <balajirrao@openmoko.org>
5 * All rights reserved.
6 *
7 * Broken down from monstrous PCF50633 driver mainly by
8 * Harald Welte, Andy Green and Werner Almesberger
9 *
10 * This program is free software; you can redistribute it and/or modify it
11 * under the terms of the GNU General Public License as published by the
12 * Free Software Foundation; either version 2 of the License, or (at your
13 * option) any later version.
14 *
15 * NOTE: This driver does not yet support subtractive ADC mode, which means
16 * you can do only one measurement per read request.
17 */
18
19#include <linux/kernel.h>
20#include <linux/module.h>
21#include <linux/init.h>
22#include <linux/device.h>
23#include <linux/platform_device.h>
24#include <linux/completion.h>
25
26#include <linux/mfd/pcf50633/core.h>
27#include <linux/mfd/pcf50633/adc.h>
28
29struct pcf50633_adc_request {
30 int mux;
31 int avg;
32 int result;
33 void (*callback)(struct pcf50633 *, void *, int);
34 void *callback_param;
35
36 /* Used in case of sync requests */
37 struct completion completion;
38
39};
40
41#define PCF50633_MAX_ADC_FIFO_DEPTH 8
42
43struct pcf50633_adc {
44 struct pcf50633 *pcf;
45
46 /* Private stuff */
47 struct pcf50633_adc_request *queue[PCF50633_MAX_ADC_FIFO_DEPTH];
48 int queue_head;
49 int queue_tail;
50 struct mutex queue_mutex;
51};
52
53static inline struct pcf50633_adc *__to_adc(struct pcf50633 *pcf)
54{
55 return platform_get_drvdata(pcf->adc_pdev);
56}
57
58static void adc_setup(struct pcf50633 *pcf, int channel, int avg)
59{
60 channel &= PCF50633_ADCC1_ADCMUX_MASK;
61
62 /* kill ratiometric, but enable ACCSW biasing */
63 pcf50633_reg_write(pcf, PCF50633_REG_ADCC2, 0x00);
64 pcf50633_reg_write(pcf, PCF50633_REG_ADCC3, 0x01);
65
66 /* start ADC conversion on selected channel */
67 pcf50633_reg_write(pcf, PCF50633_REG_ADCC1, channel | avg |
68 PCF50633_ADCC1_ADCSTART | PCF50633_ADCC1_RES_10BIT);
69}
70
71static void trigger_next_adc_job_if_any(struct pcf50633 *pcf)
72{
73 struct pcf50633_adc *adc = __to_adc(pcf);
74 int head;
75
76 mutex_lock(&adc->queue_mutex);
77
78 head = adc->queue_head;
79
80 if (!adc->queue[head]) {
81 mutex_unlock(&adc->queue_mutex);
82 return;
83 }
84 mutex_unlock(&adc->queue_mutex);
85
86 adc_setup(pcf, adc->queue[head]->mux, adc->queue[head]->avg);
87}
88
89static int
90adc_enqueue_request(struct pcf50633 *pcf, struct pcf50633_adc_request *req)
91{
92 struct pcf50633_adc *adc = __to_adc(pcf);
93 int head, tail;
94
95 mutex_lock(&adc->queue_mutex);
96
97 head = adc->queue_head;
98 tail = adc->queue_tail;
99
100 if (adc->queue[tail]) {
101 mutex_unlock(&adc->queue_mutex);
102 return -EBUSY;
103 }
104
105 adc->queue[tail] = req;
106 adc->queue_tail = (tail + 1) & (PCF50633_MAX_ADC_FIFO_DEPTH - 1);
107
108 mutex_unlock(&adc->queue_mutex);
109
110 trigger_next_adc_job_if_any(pcf);
111
112 return 0;
113}
114
115static void
116pcf50633_adc_sync_read_callback(struct pcf50633 *pcf, void *param, int result)
117{
118 struct pcf50633_adc_request *req = param;
119
120 req->result = result;
121 complete(&req->completion);
122}
123
124int pcf50633_adc_sync_read(struct pcf50633 *pcf, int mux, int avg)
125{
126 struct pcf50633_adc_request *req;
127
128 /* req is freed when the result is ready, in interrupt handler */
129 req = kzalloc(sizeof(*req), GFP_KERNEL);
130 if (!req)
131 return -ENOMEM;
132
133 req->mux = mux;
134 req->avg = avg;
135 req->callback = pcf50633_adc_sync_read_callback;
136 req->callback_param = req;
137
138 init_completion(&req->completion);
139 adc_enqueue_request(pcf, req);
140 wait_for_completion(&req->completion);
141
142 return req->result;
143}
144EXPORT_SYMBOL_GPL(pcf50633_adc_sync_read);
145
146int pcf50633_adc_async_read(struct pcf50633 *pcf, int mux, int avg,
147 void (*callback)(struct pcf50633 *, void *, int),
148 void *callback_param)
149{
150 struct pcf50633_adc_request *req;
151
152 /* req is freed when the result is ready, in interrupt handler */
153 req = kmalloc(sizeof(*req), GFP_KERNEL);
154 if (!req)
155 return -ENOMEM;
156
157 req->mux = mux;
158 req->avg = avg;
159 req->callback = callback;
160 req->callback_param = callback_param;
161
162 adc_enqueue_request(pcf, req);
163
164 return 0;
165}
166EXPORT_SYMBOL_GPL(pcf50633_adc_async_read);
167
168static int adc_result(struct pcf50633 *pcf)
169{
170 u8 adcs1, adcs3;
171 u16 result;
172
173 adcs1 = pcf50633_reg_read(pcf, PCF50633_REG_ADCS1);
174 adcs3 = pcf50633_reg_read(pcf, PCF50633_REG_ADCS3);
175 result = (adcs1 << 2) | (adcs3 & PCF50633_ADCS3_ADCDAT1L_MASK);
176
177 dev_dbg(pcf->dev, "adc result = %d\n", result);
178
179 return result;
180}
181
182static void pcf50633_adc_irq(int irq, void *data)
183{
184 struct pcf50633_adc *adc = data;
185 struct pcf50633 *pcf = adc->pcf;
186 struct pcf50633_adc_request *req;
187 int head;
188
189 mutex_lock(&adc->queue_mutex);
190 head = adc->queue_head;
191
192 req = adc->queue[head];
193 if (WARN_ON(!req)) {
194 dev_err(pcf->dev, "pcf50633-adc irq: ADC queue empty!\n");
195 mutex_unlock(&adc->queue_mutex);
196 return;
197 }
198 adc->queue[head] = NULL;
199 adc->queue_head = (head + 1) &
200 (PCF50633_MAX_ADC_FIFO_DEPTH - 1);
201
202 mutex_unlock(&adc->queue_mutex);
203
204 req->callback(pcf, req->callback_param, adc_result(pcf));
205 kfree(req);
206
207 trigger_next_adc_job_if_any(pcf);
208}
209
210static int __devinit pcf50633_adc_probe(struct platform_device *pdev)
211{
212 struct pcf50633_subdev_pdata *pdata = pdev->dev.platform_data;
213 struct pcf50633_adc *adc;
214
215 adc = kzalloc(sizeof(*adc), GFP_KERNEL);
216 if (!adc)
217 return -ENOMEM;
218
219 adc->pcf = pdata->pcf;
220 platform_set_drvdata(pdev, adc);
221
222 pcf50633_register_irq(pdata->pcf, PCF50633_IRQ_ADCRDY,
223 pcf50633_adc_irq, adc);
224
225 mutex_init(&adc->queue_mutex);
226
227 return 0;
228}
229
230static int __devexit pcf50633_adc_remove(struct platform_device *pdev)
231{
232 struct pcf50633_adc *adc = platform_get_drvdata(pdev);
233 int i, head;
234
235 pcf50633_free_irq(adc->pcf, PCF50633_IRQ_ADCRDY);
236
237 mutex_lock(&adc->queue_mutex);
238 head = adc->queue_head;
239
240 if (WARN_ON(adc->queue[head]))
241 dev_err(adc->pcf->dev,
242 "adc driver removed with request pending\n");
243
244 for (i = 0; i < PCF50633_MAX_ADC_FIFO_DEPTH; i++)
245 kfree(adc->queue[i]);
246
247 mutex_unlock(&adc->queue_mutex);
248 kfree(adc);
249
250 return 0;
251}
252
253static struct platform_driver pcf50633_adc_driver = {
254 .driver = {
255 .name = "pcf50633-adc",
256 },
257 .probe = pcf50633_adc_probe,
258 .remove = __devexit_p(pcf50633_adc_remove),
259};
260
261static int __init pcf50633_adc_init(void)
262{
263 return platform_driver_register(&pcf50633_adc_driver);
264}
265module_init(pcf50633_adc_init);
266
267static void __exit pcf50633_adc_exit(void)
268{
269 platform_driver_unregister(&pcf50633_adc_driver);
270}
271module_exit(pcf50633_adc_exit);
272
273MODULE_AUTHOR("Balaji Rao <balajirrao@openmoko.org>");
274MODULE_DESCRIPTION("PCF50633 adc driver");
275MODULE_LICENSE("GPL");
276MODULE_ALIAS("platform:pcf50633-adc");
277