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