xref: /openbmc/linux/sound/pci/oxygen/oxygen_io.c (revision 3213486f)
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 <linux/export.h>
23 #include <linux/io.h>
24 #include <sound/core.h>
25 #include <sound/mpu401.h>
26 #include "oxygen.h"
27 
28 u8 oxygen_read8(struct oxygen *chip, unsigned int reg)
29 {
30 	return inb(chip->addr + reg);
31 }
32 EXPORT_SYMBOL(oxygen_read8);
33 
34 u16 oxygen_read16(struct oxygen *chip, unsigned int reg)
35 {
36 	return inw(chip->addr + reg);
37 }
38 EXPORT_SYMBOL(oxygen_read16);
39 
40 u32 oxygen_read32(struct oxygen *chip, unsigned int reg)
41 {
42 	return inl(chip->addr + reg);
43 }
44 EXPORT_SYMBOL(oxygen_read32);
45 
46 void oxygen_write8(struct oxygen *chip, unsigned int reg, u8 value)
47 {
48 	outb(value, chip->addr + reg);
49 	chip->saved_registers._8[reg] = value;
50 }
51 EXPORT_SYMBOL(oxygen_write8);
52 
53 void oxygen_write16(struct oxygen *chip, unsigned int reg, u16 value)
54 {
55 	outw(value, chip->addr + reg);
56 	chip->saved_registers._16[reg / 2] = cpu_to_le16(value);
57 }
58 EXPORT_SYMBOL(oxygen_write16);
59 
60 void oxygen_write32(struct oxygen *chip, unsigned int reg, u32 value)
61 {
62 	outl(value, chip->addr + reg);
63 	chip->saved_registers._32[reg / 4] = cpu_to_le32(value);
64 }
65 EXPORT_SYMBOL(oxygen_write32);
66 
67 void oxygen_write8_masked(struct oxygen *chip, unsigned int reg,
68 			  u8 value, u8 mask)
69 {
70 	u8 tmp = inb(chip->addr + reg);
71 	tmp &= ~mask;
72 	tmp |= value & mask;
73 	outb(tmp, chip->addr + reg);
74 	chip->saved_registers._8[reg] = tmp;
75 }
76 EXPORT_SYMBOL(oxygen_write8_masked);
77 
78 void oxygen_write16_masked(struct oxygen *chip, unsigned int reg,
79 			   u16 value, u16 mask)
80 {
81 	u16 tmp = inw(chip->addr + reg);
82 	tmp &= ~mask;
83 	tmp |= value & mask;
84 	outw(tmp, chip->addr + reg);
85 	chip->saved_registers._16[reg / 2] = cpu_to_le16(tmp);
86 }
87 EXPORT_SYMBOL(oxygen_write16_masked);
88 
89 void oxygen_write32_masked(struct oxygen *chip, unsigned int reg,
90 			   u32 value, u32 mask)
91 {
92 	u32 tmp = inl(chip->addr + reg);
93 	tmp &= ~mask;
94 	tmp |= value & mask;
95 	outl(tmp, chip->addr + reg);
96 	chip->saved_registers._32[reg / 4] = cpu_to_le32(tmp);
97 }
98 EXPORT_SYMBOL(oxygen_write32_masked);
99 
100 static int oxygen_ac97_wait(struct oxygen *chip, unsigned int mask)
101 {
102 	u8 status = 0;
103 
104 	/*
105 	 * Reading the status register also clears the bits, so we have to save
106 	 * the read bits in status.
107 	 */
108 	wait_event_timeout(chip->ac97_waitqueue,
109 			   ({ status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
110 			      status & mask; }),
111 			   msecs_to_jiffies(1) + 1);
112 	/*
113 	 * Check even after a timeout because this function should not require
114 	 * the AC'97 interrupt to be enabled.
115 	 */
116 	status |= oxygen_read8(chip, OXYGEN_AC97_INTERRUPT_STATUS);
117 	return status & mask ? 0 : -EIO;
118 }
119 
120 /*
121  * About 10% of AC'97 register reads or writes fail to complete, but even those
122  * where the controller indicates completion aren't guaranteed to have actually
123  * happened.
124  *
125  * It's hard to assign blame to either the controller or the codec because both
126  * were made by C-Media ...
127  */
128 
129 void oxygen_write_ac97(struct oxygen *chip, unsigned int codec,
130 		       unsigned int index, u16 data)
131 {
132 	unsigned int count, succeeded;
133 	u32 reg;
134 
135 	reg = data;
136 	reg |= index << OXYGEN_AC97_REG_ADDR_SHIFT;
137 	reg |= OXYGEN_AC97_REG_DIR_WRITE;
138 	reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
139 	succeeded = 0;
140 	for (count = 5; count > 0; --count) {
141 		udelay(5);
142 		oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
143 		/* require two "completed" writes, just to be sure */
144 		if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_WRITE_DONE) >= 0 &&
145 		    ++succeeded >= 2) {
146 			chip->saved_ac97_registers[codec][index / 2] = data;
147 			return;
148 		}
149 	}
150 	dev_err(chip->card->dev, "AC'97 write timeout\n");
151 }
152 EXPORT_SYMBOL(oxygen_write_ac97);
153 
154 u16 oxygen_read_ac97(struct oxygen *chip, unsigned int codec,
155 		     unsigned int index)
156 {
157 	unsigned int count;
158 	unsigned int last_read = UINT_MAX;
159 	u32 reg;
160 
161 	reg = index << OXYGEN_AC97_REG_ADDR_SHIFT;
162 	reg |= OXYGEN_AC97_REG_DIR_READ;
163 	reg |= codec << OXYGEN_AC97_REG_CODEC_SHIFT;
164 	for (count = 5; count > 0; --count) {
165 		udelay(5);
166 		oxygen_write32(chip, OXYGEN_AC97_REGS, reg);
167 		udelay(10);
168 		if (oxygen_ac97_wait(chip, OXYGEN_AC97_INT_READ_DONE) >= 0) {
169 			u16 value = oxygen_read16(chip, OXYGEN_AC97_REGS);
170 			/* we require two consecutive reads of the same value */
171 			if (value == last_read)
172 				return value;
173 			last_read = value;
174 			/*
175 			 * Invert the register value bits to make sure that two
176 			 * consecutive unsuccessful reads do not return the same
177 			 * value.
178 			 */
179 			reg ^= 0xffff;
180 		}
181 	}
182 	dev_err(chip->card->dev, "AC'97 read timeout on codec %u\n", codec);
183 	return 0;
184 }
185 EXPORT_SYMBOL(oxygen_read_ac97);
186 
187 void oxygen_write_ac97_masked(struct oxygen *chip, unsigned int codec,
188 			      unsigned int index, u16 data, u16 mask)
189 {
190 	u16 value = oxygen_read_ac97(chip, codec, index);
191 	value &= ~mask;
192 	value |= data & mask;
193 	oxygen_write_ac97(chip, codec, index, value);
194 }
195 EXPORT_SYMBOL(oxygen_write_ac97_masked);
196 
197 static int oxygen_wait_spi(struct oxygen *chip)
198 {
199 	unsigned int count;
200 
201 	/*
202 	 * Higher timeout to be sure: 200 us;
203 	 * actual transaction should not need more than 40 us.
204 	 */
205 	for (count = 50; count > 0; count--) {
206 		udelay(4);
207 		if ((oxygen_read8(chip, OXYGEN_SPI_CONTROL) &
208 						OXYGEN_SPI_BUSY) == 0)
209 			return 0;
210 	}
211 	dev_err(chip->card->dev, "oxygen: SPI wait timeout\n");
212 	return -EIO;
213 }
214 
215 int oxygen_write_spi(struct oxygen *chip, u8 control, unsigned int data)
216 {
217 	/*
218 	 * We need to wait AFTER initiating the SPI transaction,
219 	 * otherwise read operations will not work.
220 	 */
221 	oxygen_write8(chip, OXYGEN_SPI_DATA1, data);
222 	oxygen_write8(chip, OXYGEN_SPI_DATA2, data >> 8);
223 	if (control & OXYGEN_SPI_DATA_LENGTH_3)
224 		oxygen_write8(chip, OXYGEN_SPI_DATA3, data >> 16);
225 	oxygen_write8(chip, OXYGEN_SPI_CONTROL, control);
226 	return oxygen_wait_spi(chip);
227 }
228 EXPORT_SYMBOL(oxygen_write_spi);
229 
230 void oxygen_write_i2c(struct oxygen *chip, u8 device, u8 map, u8 data)
231 {
232 	/* should not need more than about 300 us */
233 	msleep(1);
234 
235 	oxygen_write8(chip, OXYGEN_2WIRE_MAP, map);
236 	oxygen_write8(chip, OXYGEN_2WIRE_DATA, data);
237 	oxygen_write8(chip, OXYGEN_2WIRE_CONTROL,
238 		      device | OXYGEN_2WIRE_DIR_WRITE);
239 }
240 EXPORT_SYMBOL(oxygen_write_i2c);
241 
242 static void _write_uart(struct oxygen *chip, unsigned int port, u8 data)
243 {
244 	if (oxygen_read8(chip, OXYGEN_MPU401 + 1) & MPU401_TX_FULL)
245 		msleep(1);
246 	oxygen_write8(chip, OXYGEN_MPU401 + port, data);
247 }
248 
249 void oxygen_reset_uart(struct oxygen *chip)
250 {
251 	_write_uart(chip, 1, MPU401_RESET);
252 	msleep(1); /* wait for ACK */
253 	_write_uart(chip, 1, MPU401_ENTER_UART);
254 }
255 EXPORT_SYMBOL(oxygen_reset_uart);
256 
257 void oxygen_write_uart(struct oxygen *chip, u8 data)
258 {
259 	_write_uart(chip, 0, data);
260 }
261 EXPORT_SYMBOL(oxygen_write_uart);
262 
263 u16 oxygen_read_eeprom(struct oxygen *chip, unsigned int index)
264 {
265 	unsigned int timeout;
266 
267 	oxygen_write8(chip, OXYGEN_EEPROM_CONTROL,
268 		      index | OXYGEN_EEPROM_DIR_READ);
269 	for (timeout = 0; timeout < 100; ++timeout) {
270 		udelay(1);
271 		if (!(oxygen_read8(chip, OXYGEN_EEPROM_STATUS)
272 		      & OXYGEN_EEPROM_BUSY))
273 			break;
274 	}
275 	return oxygen_read16(chip, OXYGEN_EEPROM_DATA);
276 }
277 
278 void oxygen_write_eeprom(struct oxygen *chip, unsigned int index, u16 value)
279 {
280 	unsigned int timeout;
281 
282 	oxygen_write16(chip, OXYGEN_EEPROM_DATA, value);
283 	oxygen_write8(chip, OXYGEN_EEPROM_CONTROL,
284 		      index | OXYGEN_EEPROM_DIR_WRITE);
285 	for (timeout = 0; timeout < 10; ++timeout) {
286 		msleep(1);
287 		if (!(oxygen_read8(chip, OXYGEN_EEPROM_STATUS)
288 		      & OXYGEN_EEPROM_BUSY))
289 			return;
290 	}
291 	dev_err(chip->card->dev, "EEPROM write timeout\n");
292 }
293