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