xref: /openbmc/linux/sound/pci/oxygen/oxygen_io.c (revision b627b4ed)
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 <sound/mpu401.h>
24 #include <asm/io.h>
25 #include "oxygen.h"
26 
27 u8 oxygen_read8(struct oxygen *chip, unsigned int reg)
28 {
29 	return inb(chip->addr + reg);
30 }
31 EXPORT_SYMBOL(oxygen_read8);
32 
33 u16 oxygen_read16(struct oxygen *chip, unsigned int reg)
34 {
35 	return inw(chip->addr + reg);
36 }
37 EXPORT_SYMBOL(oxygen_read16);
38 
39 u32 oxygen_read32(struct oxygen *chip, unsigned int reg)
40 {
41 	return inl(chip->addr + reg);
42 }
43 EXPORT_SYMBOL(oxygen_read32);
44 
45 void oxygen_write8(struct oxygen *chip, unsigned int reg, u8 value)
46 {
47 	outb(value, chip->addr + reg);
48 	chip->saved_registers._8[reg] = value;
49 }
50 EXPORT_SYMBOL(oxygen_write8);
51 
52 void oxygen_write16(struct oxygen *chip, unsigned int reg, u16 value)
53 {
54 	outw(value, chip->addr + reg);
55 	chip->saved_registers._16[reg / 2] = cpu_to_le16(value);
56 }
57 EXPORT_SYMBOL(oxygen_write16);
58 
59 void oxygen_write32(struct oxygen *chip, unsigned int reg, u32 value)
60 {
61 	outl(value, chip->addr + reg);
62 	chip->saved_registers._32[reg / 4] = cpu_to_le32(value);
63 }
64 EXPORT_SYMBOL(oxygen_write32);
65 
66 void oxygen_write8_masked(struct oxygen *chip, unsigned int reg,
67 			  u8 value, u8 mask)
68 {
69 	u8 tmp = inb(chip->addr + reg);
70 	tmp &= ~mask;
71 	tmp |= value & mask;
72 	outb(tmp, chip->addr + reg);
73 	chip->saved_registers._8[reg] = tmp;
74 }
75 EXPORT_SYMBOL(oxygen_write8_masked);
76 
77 void oxygen_write16_masked(struct oxygen *chip, unsigned int reg,
78 			   u16 value, u16 mask)
79 {
80 	u16 tmp = inw(chip->addr + reg);
81 	tmp &= ~mask;
82 	tmp |= value & mask;
83 	outw(tmp, chip->addr + reg);
84 	chip->saved_registers._16[reg / 2] = cpu_to_le16(tmp);
85 }
86 EXPORT_SYMBOL(oxygen_write16_masked);
87 
88 void oxygen_write32_masked(struct oxygen *chip, unsigned int reg,
89 			   u32 value, u32 mask)
90 {
91 	u32 tmp = inl(chip->addr + reg);
92 	tmp &= ~mask;
93 	tmp |= value & mask;
94 	outl(tmp, chip->addr + reg);
95 	chip->saved_registers._32[reg / 4] = cpu_to_le32(tmp);
96 }
97 EXPORT_SYMBOL(oxygen_write32_masked);
98 
99 static int oxygen_ac97_wait(struct oxygen *chip, unsigned int mask)
100 {
101 	u8 status = 0;
102 
103 	/*
104 	 * Reading the status register also clears the bits, so we have to save
105 	 * the read bits in status.
106 	 */
107 	wait_event_timeout(chip->ac97_waitqueue,
108 			   ({ status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
109 			      status & mask; }),
110 			   msecs_to_jiffies(1) + 1);
111 	/*
112 	 * Check even after a timeout because this function should not require
113 	 * the AC'97 interrupt to be enabled.
114 	 */
115 	status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
116 	return status & mask ? 0 : -EIO;
117 }
118 
119 /*
120  * About 10% of AC'97 register reads or writes fail to complete, but even those
121  * where the controller indicates completion aren't guaranteed to have actually
122  * happened.
123  *
124  * It's hard to assign blame to either the controller or the codec because both
125  * were made by C-Media ...
126  */
127 
128 void oxygen_write_ac97(struct oxygen *chip, unsigned int codec,
129 		       unsigned int index, u16 data)
130 {
131 	unsigned int count, succeeded;
132 	u32 reg;
133 
134 	reg = data;
135 	reg |= index << OXYGEN_AC97_REG_ADDR_SHIFT;
136 	reg |= OXYGEN_AC97_REG_DIR_WRITE;
137 	reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
138 	succeeded = 0;
139 	for (count = 5; count > 0; --count) {
140 		udelay(5);
141 		oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
142 		/* require two "completed" writes, just to be sure */
143 		if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_WRITE_DONE) >= 0 &&
144 		    ++succeeded >= 2) {
145 			chip->saved_ac97_registers[codec][index / 2] = data;
146 			return;
147 		}
148 	}
149 	snd_printk(KERN_ERR "AC'97 write timeout\n");
150 }
151 EXPORT_SYMBOL(oxygen_write_ac97);
152 
153 u16 oxygen_read_ac97(struct oxygen *chip, unsigned int codec,
154 		     unsigned int index)
155 {
156 	unsigned int count;
157 	unsigned int last_read = UINT_MAX;
158 	u32 reg;
159 
160 	reg = index << OXYGEN_AC97_REG_ADDR_SHIFT;
161 	reg |= OXYGEN_AC97_REG_DIR_READ;
162 	reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
163 	for (count = 5; count > 0; --count) {
164 		udelay(5);
165 		oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
166 		udelay(10);
167 		if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_READ_DONE) >= 0) {
168 			u16 value = oxygen_read16(chip, OXYGEN_AC97_REGS);
169 			/* we require two consecutive reads of the same value */
170 			if (value == last_read)
171 				return value;
172 			last_read = value;
173 			/*
174 			 * Invert the register value bits to make sure that two
175 			 * consecutive unsuccessful reads do not return the same
176 			 * value.
177 			 */
178 			reg ^= 0xffff;
179 		}
180 	}
181 	snd_printk(KERN_ERR "AC'97 read timeout on codec %u\n", codec);
182 	return 0;
183 }
184 EXPORT_SYMBOL(oxygen_read_ac97);
185 
186 void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec,
187 			      unsigned int index, u16 data, u16 mask)
188 {
189 	u16 value = oxygen_read_ac97(chip, codec, index);
190 	value &= ~mask;
191 	value |= data & mask;
192 	oxygen_write_ac97(chip, codec, index, value);
193 }
194 EXPORT_SYMBOL(oxygen_write_ac97_masked);
195 
196 void oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
197 {
198 	unsigned int count;
199 
200 	/* should not need more than 7.68 us (24 * 320 ns) */
201 	count = 10;
202 	while ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) & OXYGEN_SPI_BUSY)
203 	       && count > 0) {
204 		udelay(1);
205 		--count;
206 	}
207 
208 	oxygen_write8(chip, OXYGEN_SPI_DATA1, data);
209 	oxygen_write8(chip, OXYGEN_SPI_DATA2, data >> 8);
210 	if (control & OXYGEN_SPI_DATA_LENGTH_3)
211 		oxygen_write8(chip, OXYGEN_SPI_DATA3, data >> 16);
212 	oxygen_write8(chip, OXYGEN_SPI_CONTROL, control);
213 }
214 EXPORT_SYMBOL(oxygen_write_spi);
215 
216 void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data)
217 {
218 	unsigned long timeout;
219 
220 	/* should not need more than about 300 us */
221 	timeout = jiffies + msecs_to_jiffies(1);
222 	do {
223 		if (!(oxygen_read16(chip, OXYGEN_2WIRE_BUS_STATUS)
224 		      & OXYGEN_2WIRE_BUSY))
225 			break;
226 		udelay(1);
227 		cond_resched();
228 	} while (time_after_eq(timeout, jiffies));
229 
230 	oxygen_write8(chip, OXYGEN_2WIRE_MAP, map);
231 	oxygen_write8(chip, OXYGEN_2WIRE_DATA, data);
232 	oxygen_write8(chip, OXYGEN_2WIRE_CONTROL,
233 		      device | OXYGEN_2WIRE_DIR_WRITE);
234 }
235 EXPORT_SYMBOL(oxygen_write_i2c);
236 
237 static void _write_uart(struct oxygen *chip, unsigned int port, u8 data)
238 {
239 	if (oxygen_read8(chip, OXYGEN_MPU401 + 1) & MPU401_TX_FULL)
240 		msleep(1);
241 	oxygen_write8(chip, OXYGEN_MPU401 + port, data);
242 }
243 
244 void oxygen_reset_uart(struct oxygen *chip)
245 {
246 	_write_uart(chip, 1, MPU401_RESET);
247 	msleep(1); /* wait for ACK */
248 	_write_uart(chip, 1, MPU401_ENTER_UART);
249 }
250 EXPORT_SYMBOL(oxygen_reset_uart);
251 
252 void oxygen_write_uart(struct oxygen *chip, u8 data)
253 {
254 	_write_uart(chip, 0, data);
255 }
256 EXPORT_SYMBOL(oxygen_write_uart);
257 
258 u16 oxygen_read_eeprom(struct oxygen *chip, unsigned int index)
259 {
260 	unsigned int timeout;
261 
262 	oxygen_write8(chip, OXYGEN_EEPROM_CONTROL,
263 		      index | OXYGEN_EEPROM_DIR_READ);
264 	for (timeout = 0; timeout < 100; ++timeout) {
265 		udelay(1);
266 		if (!(oxygen_read8(chip, OXYGEN_EEPROM_STATUS)
267 		      & OXYGEN_EEPROM_BUSY))
268 			break;
269 	}
270 	return oxygen_read16(chip, OXYGEN_EEPROM_DATA);
271 }
272 
273 void oxygen_write_eeprom(struct oxygen *chip, unsigned int index, u16 value)
274 {
275 	unsigned int timeout;
276 
277 	oxygen_write16(chip, OXYGEN_EEPROM_DATA, value);
278 	oxygen_write8(chip, OXYGEN_EEPROM_CONTROL,
279 		      index | OXYGEN_EEPROM_DIR_WRITE);
280 	for (timeout = 0; timeout < 10; ++timeout) {
281 		msleep(1);
282 		if (!(oxygen_read8(chip, OXYGEN_EEPROM_STATUS)
283 		      & OXYGEN_EEPROM_BUSY))
284 			return;
285 	}
286 	snd_printk(KERN_ERR "EEPROM write timeout\n");
287 }
288