1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Based on sound/arm/pxa2xx-ac97.c and sound/soc/pxa/pxa2xx-ac97.c
4 * which contain:
5 *
6 * Author: Nicolas Pitre
7 * Created: Dec 02, 2004
8 * Copyright: MontaVista Software Inc.
9 */
10
11 #include <linux/kernel.h>
12 #include <linux/platform_device.h>
13 #include <linux/interrupt.h>
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/module.h>
17 #include <linux/io.h>
18 #include <linux/gpio.h>
19 #include <linux/of_gpio.h>
20 #include <linux/soc/pxa/cpu.h>
21
22 #include <sound/pxa2xx-lib.h>
23
24 #include <linux/platform_data/asoc-pxa.h>
25
26 #include "pxa2xx-ac97-regs.h"
27
28 static DEFINE_MUTEX(car_mutex);
29 static DECLARE_WAIT_QUEUE_HEAD(gsr_wq);
30 static volatile long gsr_bits;
31 static struct clk *ac97_clk;
32 static struct clk *ac97conf_clk;
33 static int reset_gpio;
34 static void __iomem *ac97_reg_base;
35
36 /*
37 * Beware PXA27x bugs:
38 *
39 * o Slot 12 read from modem space will hang controller.
40 * o CDONE, SDONE interrupt fails after any slot 12 IO.
41 *
42 * We therefore have an hybrid approach for waiting on SDONE (interrupt or
43 * 1 jiffy timeout if interrupt never comes).
44 */
45
pxa2xx_ac97_read(int slot,unsigned short reg)46 int pxa2xx_ac97_read(int slot, unsigned short reg)
47 {
48 int val = -ENODEV;
49 u32 __iomem *reg_addr;
50
51 if (slot > 0)
52 return -ENODEV;
53
54 mutex_lock(&car_mutex);
55
56 /* set up primary or secondary codec space */
57 if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
58 reg_addr = ac97_reg_base +
59 (slot ? SMC_REG_BASE : PMC_REG_BASE);
60 else
61 reg_addr = ac97_reg_base +
62 (slot ? SAC_REG_BASE : PAC_REG_BASE);
63 reg_addr += (reg >> 1);
64
65 /* start read access across the ac97 link */
66 writel(GSR_CDONE | GSR_SDONE, ac97_reg_base + GSR);
67 gsr_bits = 0;
68 val = (readl(reg_addr) & 0xffff);
69 if (reg == AC97_GPIO_STATUS)
70 goto out;
71 if (wait_event_timeout(gsr_wq, (readl(ac97_reg_base + GSR) | gsr_bits) & GSR_SDONE, 1) <= 0 &&
72 !((readl(ac97_reg_base + GSR) | gsr_bits) & GSR_SDONE)) {
73 printk(KERN_ERR "%s: read error (ac97_reg=%d GSR=%#lx)\n",
74 __func__, reg, readl(ac97_reg_base + GSR) | gsr_bits);
75 val = -ETIMEDOUT;
76 goto out;
77 }
78
79 /* valid data now */
80 writel(GSR_CDONE | GSR_SDONE, ac97_reg_base + GSR);
81 gsr_bits = 0;
82 val = (readl(reg_addr) & 0xffff);
83 /* but we've just started another cycle... */
84 wait_event_timeout(gsr_wq, (readl(ac97_reg_base + GSR) | gsr_bits) & GSR_SDONE, 1);
85
86 out: mutex_unlock(&car_mutex);
87 return val;
88 }
89 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read);
90
pxa2xx_ac97_write(int slot,unsigned short reg,unsigned short val)91 int pxa2xx_ac97_write(int slot, unsigned short reg, unsigned short val)
92 {
93 u32 __iomem *reg_addr;
94 int ret = 0;
95
96 mutex_lock(&car_mutex);
97
98 /* set up primary or secondary codec space */
99 if (cpu_is_pxa25x() && reg == AC97_GPIO_STATUS)
100 reg_addr = ac97_reg_base +
101 (slot ? SMC_REG_BASE : PMC_REG_BASE);
102 else
103 reg_addr = ac97_reg_base +
104 (slot ? SAC_REG_BASE : PAC_REG_BASE);
105 reg_addr += (reg >> 1);
106
107 writel(GSR_CDONE | GSR_SDONE, ac97_reg_base + GSR);
108 gsr_bits = 0;
109 writel(val, reg_addr);
110 if (wait_event_timeout(gsr_wq, (readl(ac97_reg_base + GSR) | gsr_bits) & GSR_CDONE, 1) <= 0 &&
111 !((readl(ac97_reg_base + GSR) | gsr_bits) & GSR_CDONE)) {
112 printk(KERN_ERR "%s: write error (ac97_reg=%d GSR=%#lx)\n",
113 __func__, reg, readl(ac97_reg_base + GSR) | gsr_bits);
114 ret = -EIO;
115 }
116
117 mutex_unlock(&car_mutex);
118 return ret;
119 }
120 EXPORT_SYMBOL_GPL(pxa2xx_ac97_write);
121
122 #ifdef CONFIG_PXA25x
pxa_ac97_warm_pxa25x(void)123 static inline void pxa_ac97_warm_pxa25x(void)
124 {
125 gsr_bits = 0;
126
127 writel(readl(ac97_reg_base + GCR) | (GCR_WARM_RST), ac97_reg_base + GCR);
128 }
129
pxa_ac97_cold_pxa25x(void)130 static inline void pxa_ac97_cold_pxa25x(void)
131 {
132 writel(readl(ac97_reg_base + GCR) & ( GCR_COLD_RST), ac97_reg_base + GCR); /* clear everything but nCRST */
133 writel(readl(ac97_reg_base + GCR) & (~GCR_COLD_RST), ac97_reg_base + GCR); /* then assert nCRST */
134
135 gsr_bits = 0;
136
137 writel(GCR_COLD_RST, ac97_reg_base + GCR);
138 }
139 #endif
140
141 #ifdef CONFIG_PXA27x
pxa_ac97_warm_pxa27x(void)142 static inline void pxa_ac97_warm_pxa27x(void)
143 {
144 gsr_bits = 0;
145
146 /* warm reset broken on Bulverde, so manually keep AC97 reset high */
147 pxa27x_configure_ac97reset(reset_gpio, true);
148 udelay(10);
149 writel(readl(ac97_reg_base + GCR) | (GCR_WARM_RST), ac97_reg_base + GCR);
150 pxa27x_configure_ac97reset(reset_gpio, false);
151 udelay(500);
152 }
153
pxa_ac97_cold_pxa27x(void)154 static inline void pxa_ac97_cold_pxa27x(void)
155 {
156 writel(readl(ac97_reg_base + GCR) & ( GCR_COLD_RST), ac97_reg_base + GCR); /* clear everything but nCRST */
157 writel(readl(ac97_reg_base + GCR) & (~GCR_COLD_RST), ac97_reg_base + GCR); /* then assert nCRST */
158
159 gsr_bits = 0;
160
161 /* PXA27x Developers Manual section 13.5.2.2.1 */
162 clk_prepare_enable(ac97conf_clk);
163 udelay(5);
164 clk_disable_unprepare(ac97conf_clk);
165 writel(GCR_COLD_RST | GCR_WARM_RST, ac97_reg_base + GCR);
166 }
167 #endif
168
169 #ifdef CONFIG_PXA3xx
pxa_ac97_warm_pxa3xx(void)170 static inline void pxa_ac97_warm_pxa3xx(void)
171 {
172 gsr_bits = 0;
173
174 /* Can't use interrupts */
175 writel(readl(ac97_reg_base + GCR) | (GCR_WARM_RST), ac97_reg_base + GCR);
176 }
177
pxa_ac97_cold_pxa3xx(void)178 static inline void pxa_ac97_cold_pxa3xx(void)
179 {
180 /* Hold CLKBPB for 100us */
181 writel(0, ac97_reg_base + GCR);
182 writel(GCR_CLKBPB, ac97_reg_base + GCR);
183 udelay(100);
184 writel(0, ac97_reg_base + GCR);
185
186 writel(readl(ac97_reg_base + GCR) & ( GCR_COLD_RST), ac97_reg_base + GCR); /* clear everything but nCRST */
187 writel(readl(ac97_reg_base + GCR) & (~GCR_COLD_RST), ac97_reg_base + GCR); /* then assert nCRST */
188
189 gsr_bits = 0;
190
191 /* Can't use interrupts on PXA3xx */
192 writel(readl(ac97_reg_base + GCR) & (~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN)), ac97_reg_base + GCR);
193
194 writel(GCR_WARM_RST | GCR_COLD_RST, ac97_reg_base + GCR);
195 }
196 #endif
197
pxa2xx_ac97_try_warm_reset(void)198 bool pxa2xx_ac97_try_warm_reset(void)
199 {
200 unsigned long gsr;
201 unsigned int timeout = 100;
202
203 #ifdef CONFIG_PXA25x
204 if (cpu_is_pxa25x())
205 pxa_ac97_warm_pxa25x();
206 else
207 #endif
208 #ifdef CONFIG_PXA27x
209 if (cpu_is_pxa27x())
210 pxa_ac97_warm_pxa27x();
211 else
212 #endif
213 #ifdef CONFIG_PXA3xx
214 if (cpu_is_pxa3xx())
215 pxa_ac97_warm_pxa3xx();
216 else
217 #endif
218 snd_BUG();
219
220 while (!((readl(ac97_reg_base + GSR) | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
221 mdelay(1);
222
223 gsr = readl(ac97_reg_base + GSR) | gsr_bits;
224 if (!(gsr & (GSR_PCR | GSR_SCR))) {
225 printk(KERN_INFO "%s: warm reset timeout (GSR=%#lx)\n",
226 __func__, gsr);
227
228 return false;
229 }
230
231 return true;
232 }
233 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_warm_reset);
234
pxa2xx_ac97_try_cold_reset(void)235 bool pxa2xx_ac97_try_cold_reset(void)
236 {
237 unsigned long gsr;
238 unsigned int timeout = 1000;
239
240 #ifdef CONFIG_PXA25x
241 if (cpu_is_pxa25x())
242 pxa_ac97_cold_pxa25x();
243 else
244 #endif
245 #ifdef CONFIG_PXA27x
246 if (cpu_is_pxa27x())
247 pxa_ac97_cold_pxa27x();
248 else
249 #endif
250 #ifdef CONFIG_PXA3xx
251 if (cpu_is_pxa3xx())
252 pxa_ac97_cold_pxa3xx();
253 else
254 #endif
255 snd_BUG();
256
257 while (!((readl(ac97_reg_base + GSR) | gsr_bits) & (GSR_PCR | GSR_SCR)) && timeout--)
258 mdelay(1);
259
260 gsr = readl(ac97_reg_base + GSR) | gsr_bits;
261 if (!(gsr & (GSR_PCR | GSR_SCR))) {
262 printk(KERN_INFO "%s: cold reset timeout (GSR=%#lx)\n",
263 __func__, gsr);
264
265 return false;
266 }
267
268 return true;
269 }
270 EXPORT_SYMBOL_GPL(pxa2xx_ac97_try_cold_reset);
271
272
pxa2xx_ac97_finish_reset(void)273 void pxa2xx_ac97_finish_reset(void)
274 {
275 u32 gcr = readl(ac97_reg_base + GCR);
276 gcr &= ~(GCR_PRIRDY_IEN|GCR_SECRDY_IEN);
277 gcr |= GCR_SDONE_IE|GCR_CDONE_IE;
278 writel(gcr, ac97_reg_base + GCR);
279 }
280 EXPORT_SYMBOL_GPL(pxa2xx_ac97_finish_reset);
281
pxa2xx_ac97_irq(int irq,void * dev_id)282 static irqreturn_t pxa2xx_ac97_irq(int irq, void *dev_id)
283 {
284 long status;
285
286 status = readl(ac97_reg_base + GSR);
287 if (status) {
288 writel(status, ac97_reg_base + GSR);
289 gsr_bits |= status;
290 wake_up(&gsr_wq);
291
292 /* Although we don't use those we still need to clear them
293 since they tend to spuriously trigger when MMC is used
294 (hardware bug? go figure)... */
295 if (cpu_is_pxa27x()) {
296 writel(MISR_EOC, ac97_reg_base + MISR);
297 writel(PISR_EOC, ac97_reg_base + PISR);
298 writel(MCSR_EOC, ac97_reg_base + MCSR);
299 }
300
301 return IRQ_HANDLED;
302 }
303
304 return IRQ_NONE;
305 }
306
307 #ifdef CONFIG_PM
pxa2xx_ac97_hw_suspend(void)308 int pxa2xx_ac97_hw_suspend(void)
309 {
310 writel(readl(ac97_reg_base + GCR) | (GCR_ACLINK_OFF), ac97_reg_base + GCR);
311 clk_disable_unprepare(ac97_clk);
312 return 0;
313 }
314 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_suspend);
315
pxa2xx_ac97_hw_resume(void)316 int pxa2xx_ac97_hw_resume(void)
317 {
318 clk_prepare_enable(ac97_clk);
319 return 0;
320 }
321 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_resume);
322 #endif
323
pxa2xx_ac97_hw_probe(struct platform_device * dev)324 int pxa2xx_ac97_hw_probe(struct platform_device *dev)
325 {
326 int ret;
327 int irq;
328 pxa2xx_audio_ops_t *pdata = dev->dev.platform_data;
329
330 ac97_reg_base = devm_platform_ioremap_resource(dev, 0);
331 if (IS_ERR(ac97_reg_base)) {
332 dev_err(&dev->dev, "Missing MMIO resource\n");
333 return PTR_ERR(ac97_reg_base);
334 }
335
336 if (pdata) {
337 switch (pdata->reset_gpio) {
338 case 95:
339 case 113:
340 reset_gpio = pdata->reset_gpio;
341 break;
342 case 0:
343 reset_gpio = 113;
344 break;
345 case -1:
346 break;
347 default:
348 dev_err(&dev->dev, "Invalid reset GPIO %d\n",
349 pdata->reset_gpio);
350 }
351 } else if (!pdata && dev->dev.of_node) {
352 pdata = devm_kzalloc(&dev->dev, sizeof(*pdata), GFP_KERNEL);
353 if (!pdata)
354 return -ENOMEM;
355 pdata->reset_gpio = of_get_named_gpio(dev->dev.of_node,
356 "reset-gpios", 0);
357 if (pdata->reset_gpio == -ENOENT)
358 pdata->reset_gpio = -1;
359 else if (pdata->reset_gpio < 0)
360 return pdata->reset_gpio;
361 reset_gpio = pdata->reset_gpio;
362 } else {
363 if (cpu_is_pxa27x())
364 reset_gpio = 113;
365 }
366
367 if (cpu_is_pxa27x()) {
368 /*
369 * This gpio is needed for a work-around to a bug in the ac97
370 * controller during warm reset. The direction and level is set
371 * here so that it is an output driven high when switching from
372 * AC97_nRESET alt function to generic gpio.
373 */
374 ret = gpio_request_one(reset_gpio, GPIOF_OUT_INIT_HIGH,
375 "pxa27x ac97 reset");
376 if (ret < 0) {
377 pr_err("%s: gpio_request_one() failed: %d\n",
378 __func__, ret);
379 goto err_conf;
380 }
381 pxa27x_configure_ac97reset(reset_gpio, false);
382
383 ac97conf_clk = clk_get(&dev->dev, "AC97CONFCLK");
384 if (IS_ERR(ac97conf_clk)) {
385 ret = PTR_ERR(ac97conf_clk);
386 ac97conf_clk = NULL;
387 goto err_conf;
388 }
389 }
390
391 ac97_clk = clk_get(&dev->dev, "AC97CLK");
392 if (IS_ERR(ac97_clk)) {
393 ret = PTR_ERR(ac97_clk);
394 ac97_clk = NULL;
395 goto err_clk;
396 }
397
398 ret = clk_prepare_enable(ac97_clk);
399 if (ret)
400 goto err_clk2;
401
402 irq = platform_get_irq(dev, 0);
403 if (irq < 0) {
404 ret = irq;
405 goto err_irq;
406 }
407
408 ret = request_irq(irq, pxa2xx_ac97_irq, 0, "AC97", NULL);
409 if (ret < 0)
410 goto err_irq;
411
412 return 0;
413
414 err_irq:
415 writel(readl(ac97_reg_base + GCR) | (GCR_ACLINK_OFF), ac97_reg_base + GCR);
416 err_clk2:
417 clk_put(ac97_clk);
418 ac97_clk = NULL;
419 err_clk:
420 if (ac97conf_clk) {
421 clk_put(ac97conf_clk);
422 ac97conf_clk = NULL;
423 }
424 err_conf:
425 return ret;
426 }
427 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_probe);
428
pxa2xx_ac97_hw_remove(struct platform_device * dev)429 void pxa2xx_ac97_hw_remove(struct platform_device *dev)
430 {
431 if (cpu_is_pxa27x())
432 gpio_free(reset_gpio);
433 writel(readl(ac97_reg_base + GCR) | (GCR_ACLINK_OFF), ac97_reg_base + GCR);
434 free_irq(platform_get_irq(dev, 0), NULL);
435 if (ac97conf_clk) {
436 clk_put(ac97conf_clk);
437 ac97conf_clk = NULL;
438 }
439 clk_disable_unprepare(ac97_clk);
440 clk_put(ac97_clk);
441 ac97_clk = NULL;
442 }
443 EXPORT_SYMBOL_GPL(pxa2xx_ac97_hw_remove);
444
pxa2xx_ac97_read_modr(void)445 u32 pxa2xx_ac97_read_modr(void)
446 {
447 if (!ac97_reg_base)
448 return 0;
449
450 return readl(ac97_reg_base + MODR);
451 }
452 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read_modr);
453
pxa2xx_ac97_read_misr(void)454 u32 pxa2xx_ac97_read_misr(void)
455 {
456 if (!ac97_reg_base)
457 return 0;
458
459 return readl(ac97_reg_base + MISR);
460 }
461 EXPORT_SYMBOL_GPL(pxa2xx_ac97_read_misr);
462
463 MODULE_AUTHOR("Nicolas Pitre");
464 MODULE_DESCRIPTION("Intel/Marvell PXA sound library");
465 MODULE_LICENSE("GPL");
466
467
