Merge Btrfs into fs/btrfs
[linux-2.6] / sound / pci / oxygen / oxygen_io.c
1 /*
2  * C-Media CMI8788 driver - helper functions
3  *
4  * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
5  *
6  *
7  *  This driver is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License, version 2.
9  *
10  *  This driver is distributed in the hope that it will be useful,
11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  *  GNU General Public License for more details.
14  *
15  *  You should have received a copy of the GNU General Public License
16  *  along with this driver; if not, write to the Free Software
17  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
18  */
19
20 #include <linux/delay.h>
21 #include <linux/sched.h>
22 #include <sound/core.h>
23 #include <asm/io.h>
24 #include "oxygen.h"
25
26 u8 oxygen_read8(struct oxygen *chip, unsigned int reg)
27 {
28         return inb(chip->addr + reg);
29 }
30 EXPORT_SYMBOL(oxygen_read8);
31
32 u16 oxygen_read16(struct oxygen *chip, unsigned int reg)
33 {
34         return inw(chip->addr + reg);
35 }
36 EXPORT_SYMBOL(oxygen_read16);
37
38 u32 oxygen_read32(struct oxygen *chip, unsigned int reg)
39 {
40         return inl(chip->addr + reg);
41 }
42 EXPORT_SYMBOL(oxygen_read32);
43
44 void oxygen_write8(struct oxygen *chip, unsigned int reg, u8 value)
45 {
46         outb(value, chip->addr + reg);
47         chip->saved_registers._8[reg] = value;
48 }
49 EXPORT_SYMBOL(oxygen_write8);
50
51 void oxygen_write16(struct oxygen *chip, unsigned int reg, u16 value)
52 {
53         outw(value, chip->addr + reg);
54         chip->saved_registers._16[reg / 2] = cpu_to_le16(value);
55 }
56 EXPORT_SYMBOL(oxygen_write16);
57
58 void oxygen_write32(struct oxygen *chip, unsigned int reg, u32 value)
59 {
60         outl(value, chip->addr + reg);
61         chip->saved_registers._32[reg / 4] = cpu_to_le32(value);
62 }
63 EXPORT_SYMBOL(oxygen_write32);
64
65 void oxygen_write8_masked(struct oxygen *chip, unsigned int reg,
66                           u8 value, u8 mask)
67 {
68         u8 tmp = inb(chip->addr + reg);
69         tmp &= ~mask;
70         tmp |= value & mask;
71         outb(tmp, chip->addr + reg);
72         chip->saved_registers._8[reg] = tmp;
73 }
74 EXPORT_SYMBOL(oxygen_write8_masked);
75
76 void oxygen_write16_masked(struct oxygen *chip, unsigned int reg,
77                            u16 value, u16 mask)
78 {
79         u16 tmp = inw(chip->addr + reg);
80         tmp &= ~mask;
81         tmp |= value & mask;
82         outw(tmp, chip->addr + reg);
83         chip->saved_registers._16[reg / 2] = cpu_to_le16(tmp);
84 }
85 EXPORT_SYMBOL(oxygen_write16_masked);
86
87 void oxygen_write32_masked(struct oxygen *chip, unsigned int reg,
88                            u32 value, u32 mask)
89 {
90         u32 tmp = inl(chip->addr + reg);
91         tmp &= ~mask;
92         tmp |= value & mask;
93         outl(tmp, chip->addr + reg);
94         chip->saved_registers._32[reg / 4] = cpu_to_le32(tmp);
95 }
96 EXPORT_SYMBOL(oxygen_write32_masked);
97
98 static int oxygen_ac97_wait(struct oxygen *chip, unsigned int mask)
99 {
100         u8 status = 0;
101
102         /*
103          * Reading the status register also clears the bits, so we have to save
104          * the read bits in status.
105          */
106         wait_event_timeout(chip->ac97_waitqueue,
107                            ({ status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
108                               status & mask; }),
109                            msecs_to_jiffies(1) + 1);
110         /*
111          * Check even after a timeout because this function should not require
112          * the AC'97 interrupt to be enabled.
113          */
114         status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
115         return status & mask ? 0 : -EIO;
116 }
117
118 /*
119  * About 10% of AC'97 register reads or writes fail to complete, but even those
120  * where the controller indicates completion aren't guaranteed to have actually
121  * happened.
122  *
123  * It's hard to assign blame to either the controller or the codec because both
124  * were made by C-Media ...
125  */
126
127 void oxygen_write_ac97(struct oxygen *chip, unsigned int codec,
128                        unsigned int index, u16 data)
129 {
130         unsigned int count, succeeded;
131         u32 reg;
132
133         reg = data;
134         reg |= index << OXYGEN_AC97_REG_ADDR_SHIFT;
135         reg |= OXYGEN_AC97_REG_DIR_WRITE;
136         reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
137         succeeded = 0;
138         for (count = 5; count > 0; --count) {
139                 udelay(5);
140                 oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
141                 /* require two "completed" writes, just to be sure */
142                 if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_WRITE_DONE) >= 0 &&
143                     ++succeeded >= 2) {
144                         chip->saved_ac97_registers[codec][index / 2] = data;
145                         return;
146                 }
147         }
148         snd_printk(KERN_ERR "AC'97 write timeout\n");
149 }
150 EXPORT_SYMBOL(oxygen_write_ac97);
151
152 u16 oxygen_read_ac97(struct oxygen *chip, unsigned int codec,
153                      unsigned int index)
154 {
155         unsigned int count;
156         unsigned int last_read = UINT_MAX;
157         u32 reg;
158
159         reg = index << OXYGEN_AC97_REG_ADDR_SHIFT;
160         reg |= OXYGEN_AC97_REG_DIR_READ;
161         reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
162         for (count = 5; count > 0; --count) {
163                 udelay(5);
164                 oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
165                 udelay(10);
166                 if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_READ_DONE) >= 0) {
167                         u16 value = oxygen_read16(chip, OXYGEN_AC97_REGS);
168                         /* we require two consecutive reads of the same value */
169                         if (value == last_read)
170                                 return value;
171                         last_read = value;
172                         /*
173                          * Invert the register value bits to make sure that two
174                          * consecutive unsuccessful reads do not return the same
175                          * value.
176                          */
177                         reg ^= 0xffff;
178                 }
179         }
180         snd_printk(KERN_ERR "AC'97 read timeout on codec %u\n", codec);
181         return 0;
182 }
183 EXPORT_SYMBOL(oxygen_read_ac97);
184
185 void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec,
186                               unsigned int index, u16 data, u16 mask)
187 {
188         u16 value = oxygen_read_ac97(chip, codec, index);
189         value &= ~mask;
190         value |= data & mask;
191         oxygen_write_ac97(chip, codec, index, value);
192 }
193 EXPORT_SYMBOL(oxygen_write_ac97_masked);
194
195 void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
196 {
197         unsigned int count;
198
199         /* should not need more than 7.68 us (24 * 320 ns) */
200         count = 10;
201         while ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) & OXYGEN_SPI_BUSY)
202                && count > 0) {
203                 udelay(1);
204                 --count;
205         }
206
207         oxygen_write8(chip, OXYGEN_SPI_DATA1, data);
208         oxygen_write8(chip, OXYGEN_SPI_DATA2, data >> 8);
209         if (control & OXYGEN_SPI_DATA_LENGTH_3)
210                 oxygen_write8(chip, OXYGEN_SPI_DATA3, data >> 16);
211         oxygen_write8(chip, OXYGEN_SPI_CONTROL, control);
212 }
213 EXPORT_SYMBOL(oxygen_write_spi);
214
215 void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data)
216 {
217         unsigned long timeout;
218
219         /* should not need more than about 300 us */
220         timeout = jiffies + msecs_to_jiffies(1);
221         do {
222                 if (!(oxygen_read16(chip, OXYGEN_2WIRE_BUS_STATUS)
223                       & OXYGEN_2WIRE_BUSY))
224                         break;
225                 udelay(1);
226                 cond_resched();
227         } while (time_after_eq(timeout, jiffies));
228
229         oxygen_write8(chip, OXYGEN_2WIRE_MAP, map);
230         oxygen_write8(chip, OXYGEN_2WIRE_DATA, data);
231         oxygen_write8(chip, OXYGEN_2WIRE_CONTROL,
232                       device | OXYGEN_2WIRE_DIR_WRITE);
233 }
234 EXPORT_SYMBOL(oxygen_write_i2c);