1c942fddfSThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
2b285192aSMauro Carvalho Chehab /*
3b285192aSMauro Carvalho Chehab * Stereo and SAP detection for cx88
4b285192aSMauro Carvalho Chehab *
5b285192aSMauro Carvalho Chehab * Copyright (c) 2009 Marton Balint <cus@fazekas.hu>
6b285192aSMauro Carvalho Chehab */
7b285192aSMauro Carvalho Chehab
865bc2fe8SMauro Carvalho Chehab #include "cx88.h"
965bc2fe8SMauro Carvalho Chehab #include "cx88-reg.h"
1065bc2fe8SMauro Carvalho Chehab
11b285192aSMauro Carvalho Chehab #include <linux/slab.h>
12b285192aSMauro Carvalho Chehab #include <linux/kernel.h>
13b285192aSMauro Carvalho Chehab #include <linux/module.h>
14b285192aSMauro Carvalho Chehab #include <linux/jiffies.h>
15b285192aSMauro Carvalho Chehab #include <asm/div64.h>
16b285192aSMauro Carvalho Chehab
17b285192aSMauro Carvalho Chehab #define INT_PI ((s32)(3.141592653589 * 32768.0))
18b285192aSMauro Carvalho Chehab
19b285192aSMauro Carvalho Chehab #define compat_remainder(a, b) \
20b285192aSMauro Carvalho Chehab ((float)(((s32)((a) * 100)) % ((s32)((b) * 100))) / 100.0)
21b285192aSMauro Carvalho Chehab
22b285192aSMauro Carvalho Chehab #define baseband_freq(carrier, srate, tone) ((s32)( \
23b285192aSMauro Carvalho Chehab (compat_remainder(carrier + tone, srate)) / srate * 2 * INT_PI))
24b285192aSMauro Carvalho Chehab
25399426caSMauro Carvalho Chehab /*
26399426caSMauro Carvalho Chehab * We calculate the baseband frequencies of the carrier and the pilot tones
27*3b12018dSSlark Xiao * based on the sampling rate of the audio rds fifo.
28399426caSMauro Carvalho Chehab */
29b285192aSMauro Carvalho Chehab
30b285192aSMauro Carvalho Chehab #define FREQ_A2_CARRIER baseband_freq(54687.5, 2689.36, 0.0)
31b285192aSMauro Carvalho Chehab #define FREQ_A2_DUAL baseband_freq(54687.5, 2689.36, 274.1)
32b285192aSMauro Carvalho Chehab #define FREQ_A2_STEREO baseband_freq(54687.5, 2689.36, 117.5)
33b285192aSMauro Carvalho Chehab
34399426caSMauro Carvalho Chehab /*
35399426caSMauro Carvalho Chehab * The frequencies below are from the reference driver. They probably need
36b285192aSMauro Carvalho Chehab * further adjustments, because they are not tested at all. You may even need
37b285192aSMauro Carvalho Chehab * to play a bit with the registers of the chip to select the proper signal
38b285192aSMauro Carvalho Chehab * for the input of the audio rds fifo, and measure it's sampling rate to
39399426caSMauro Carvalho Chehab * calculate the proper baseband frequencies...
40399426caSMauro Carvalho Chehab */
41b285192aSMauro Carvalho Chehab
42b285192aSMauro Carvalho Chehab #define FREQ_A2M_CARRIER ((s32)(2.114516 * 32768.0))
43b285192aSMauro Carvalho Chehab #define FREQ_A2M_DUAL ((s32)(2.754916 * 32768.0))
44b285192aSMauro Carvalho Chehab #define FREQ_A2M_STEREO ((s32)(2.462326 * 32768.0))
45b285192aSMauro Carvalho Chehab
46b285192aSMauro Carvalho Chehab #define FREQ_EIAJ_CARRIER ((s32)(1.963495 * 32768.0)) /* 5pi/8 */
47b285192aSMauro Carvalho Chehab #define FREQ_EIAJ_DUAL ((s32)(2.562118 * 32768.0))
48b285192aSMauro Carvalho Chehab #define FREQ_EIAJ_STEREO ((s32)(2.601053 * 32768.0))
49b285192aSMauro Carvalho Chehab
50b285192aSMauro Carvalho Chehab #define FREQ_BTSC_DUAL ((s32)(1.963495 * 32768.0)) /* 5pi/8 */
51b285192aSMauro Carvalho Chehab #define FREQ_BTSC_DUAL_REF ((s32)(1.374446 * 32768.0)) /* 7pi/16 */
52b285192aSMauro Carvalho Chehab
53b285192aSMauro Carvalho Chehab #define FREQ_BTSC_SAP ((s32)(2.471532 * 32768.0))
54b285192aSMauro Carvalho Chehab #define FREQ_BTSC_SAP_REF ((s32)(1.730072 * 32768.0))
55b285192aSMauro Carvalho Chehab
56b285192aSMauro Carvalho Chehab /* The spectrum of the signal should be empty between these frequencies. */
57b285192aSMauro Carvalho Chehab #define FREQ_NOISE_START ((s32)(0.100000 * 32768.0))
58b285192aSMauro Carvalho Chehab #define FREQ_NOISE_END ((s32)(1.200000 * 32768.0))
59b285192aSMauro Carvalho Chehab
60b285192aSMauro Carvalho Chehab static unsigned int dsp_debug;
61b285192aSMauro Carvalho Chehab module_param(dsp_debug, int, 0644);
62b285192aSMauro Carvalho Chehab MODULE_PARM_DESC(dsp_debug, "enable audio dsp debug messages");
63b285192aSMauro Carvalho Chehab
6465bc2fe8SMauro Carvalho Chehab #define dprintk(level, fmt, arg...) do { \
6565bc2fe8SMauro Carvalho Chehab if (dsp_debug >= level) \
6665bc2fe8SMauro Carvalho Chehab printk(KERN_DEBUG pr_fmt("%s: dsp:" fmt), \
6765bc2fe8SMauro Carvalho Chehab __func__, ##arg); \
6865bc2fe8SMauro Carvalho Chehab } while (0)
69b285192aSMauro Carvalho Chehab
int_cos(u32 x)70b285192aSMauro Carvalho Chehab static s32 int_cos(u32 x)
71b285192aSMauro Carvalho Chehab {
72b285192aSMauro Carvalho Chehab u32 t2, t4, t6, t8;
73b285192aSMauro Carvalho Chehab s32 ret;
74b285192aSMauro Carvalho Chehab u16 period = x / INT_PI;
757b61ba8fSMauro Carvalho Chehab
76b285192aSMauro Carvalho Chehab if (period % 2)
77b285192aSMauro Carvalho Chehab return -int_cos(x - INT_PI);
78b285192aSMauro Carvalho Chehab x = x % INT_PI;
79b285192aSMauro Carvalho Chehab if (x > INT_PI / 2)
80b285192aSMauro Carvalho Chehab return -int_cos(INT_PI / 2 - (x % (INT_PI / 2)));
81399426caSMauro Carvalho Chehab /*
82399426caSMauro Carvalho Chehab * Now x is between 0 and INT_PI/2.
83399426caSMauro Carvalho Chehab * To calculate cos(x) we use it's Taylor polinom.
84399426caSMauro Carvalho Chehab */
85b285192aSMauro Carvalho Chehab t2 = x * x / 32768 / 2;
86b285192aSMauro Carvalho Chehab t4 = t2 * x / 32768 * x / 32768 / 3 / 4;
87b285192aSMauro Carvalho Chehab t6 = t4 * x / 32768 * x / 32768 / 5 / 6;
88b285192aSMauro Carvalho Chehab t8 = t6 * x / 32768 * x / 32768 / 7 / 8;
89b285192aSMauro Carvalho Chehab ret = 32768 - t2 + t4 - t6 + t8;
90b285192aSMauro Carvalho Chehab return ret;
91b285192aSMauro Carvalho Chehab }
92b285192aSMauro Carvalho Chehab
int_goertzel(s16 x[],u32 N,u32 freq)93b285192aSMauro Carvalho Chehab static u32 int_goertzel(s16 x[], u32 N, u32 freq)
94b285192aSMauro Carvalho Chehab {
95399426caSMauro Carvalho Chehab /*
96399426caSMauro Carvalho Chehab * We use the Goertzel algorithm to determine the power of the
97399426caSMauro Carvalho Chehab * given frequency in the signal
98399426caSMauro Carvalho Chehab */
99b285192aSMauro Carvalho Chehab s32 s_prev = 0;
100b285192aSMauro Carvalho Chehab s32 s_prev2 = 0;
101b285192aSMauro Carvalho Chehab s32 coeff = 2 * int_cos(freq);
102b285192aSMauro Carvalho Chehab u32 i;
103b285192aSMauro Carvalho Chehab
104b285192aSMauro Carvalho Chehab u64 tmp;
105b285192aSMauro Carvalho Chehab u32 divisor;
106b285192aSMauro Carvalho Chehab
107b285192aSMauro Carvalho Chehab for (i = 0; i < N; i++) {
108b285192aSMauro Carvalho Chehab s32 s = x[i] + ((s64)coeff * s_prev / 32768) - s_prev2;
1097b61ba8fSMauro Carvalho Chehab
110b285192aSMauro Carvalho Chehab s_prev2 = s_prev;
111b285192aSMauro Carvalho Chehab s_prev = s;
112b285192aSMauro Carvalho Chehab }
113b285192aSMauro Carvalho Chehab
114b285192aSMauro Carvalho Chehab tmp = (s64)s_prev2 * s_prev2 + (s64)s_prev * s_prev -
115b285192aSMauro Carvalho Chehab (s64)coeff * s_prev2 * s_prev / 32768;
116b285192aSMauro Carvalho Chehab
117399426caSMauro Carvalho Chehab /*
118399426caSMauro Carvalho Chehab * XXX: N must be low enough so that N*N fits in s32.
119399426caSMauro Carvalho Chehab * Else we need two divisions.
120399426caSMauro Carvalho Chehab */
121b285192aSMauro Carvalho Chehab divisor = N * N;
122b285192aSMauro Carvalho Chehab do_div(tmp, divisor);
123b285192aSMauro Carvalho Chehab
124b285192aSMauro Carvalho Chehab return (u32)tmp;
125b285192aSMauro Carvalho Chehab }
126b285192aSMauro Carvalho Chehab
freq_magnitude(s16 x[],u32 N,u32 freq)127b285192aSMauro Carvalho Chehab static u32 freq_magnitude(s16 x[], u32 N, u32 freq)
128b285192aSMauro Carvalho Chehab {
129b285192aSMauro Carvalho Chehab u32 sum = int_goertzel(x, N, freq);
1307b61ba8fSMauro Carvalho Chehab
131b285192aSMauro Carvalho Chehab return (u32)int_sqrt(sum);
132b285192aSMauro Carvalho Chehab }
133b285192aSMauro Carvalho Chehab
noise_magnitude(s16 x[],u32 N,u32 freq_start,u32 freq_end)134b285192aSMauro Carvalho Chehab static u32 noise_magnitude(s16 x[], u32 N, u32 freq_start, u32 freq_end)
135b285192aSMauro Carvalho Chehab {
136b285192aSMauro Carvalho Chehab int i;
137b285192aSMauro Carvalho Chehab u32 sum = 0;
138b285192aSMauro Carvalho Chehab u32 freq_step;
139b285192aSMauro Carvalho Chehab int samples = 5;
140b285192aSMauro Carvalho Chehab
141b285192aSMauro Carvalho Chehab if (N > 192) {
142b285192aSMauro Carvalho Chehab /* The last 192 samples are enough for noise detection */
143b285192aSMauro Carvalho Chehab x += (N - 192);
144b285192aSMauro Carvalho Chehab N = 192;
145b285192aSMauro Carvalho Chehab }
146b285192aSMauro Carvalho Chehab
147b285192aSMauro Carvalho Chehab freq_step = (freq_end - freq_start) / (samples - 1);
148b285192aSMauro Carvalho Chehab
149b285192aSMauro Carvalho Chehab for (i = 0; i < samples; i++) {
150b285192aSMauro Carvalho Chehab sum += int_goertzel(x, N, freq_start);
151b285192aSMauro Carvalho Chehab freq_start += freq_step;
152b285192aSMauro Carvalho Chehab }
153b285192aSMauro Carvalho Chehab
154b285192aSMauro Carvalho Chehab return (u32)int_sqrt(sum / samples);
155b285192aSMauro Carvalho Chehab }
156b285192aSMauro Carvalho Chehab
detect_a2_a2m_eiaj(struct cx88_core * core,s16 x[],u32 N)157b285192aSMauro Carvalho Chehab static s32 detect_a2_a2m_eiaj(struct cx88_core *core, s16 x[], u32 N)
158b285192aSMauro Carvalho Chehab {
159b285192aSMauro Carvalho Chehab s32 carrier, stereo, dual, noise;
160b285192aSMauro Carvalho Chehab s32 carrier_freq, stereo_freq, dual_freq;
161b285192aSMauro Carvalho Chehab s32 ret;
162b285192aSMauro Carvalho Chehab
163b285192aSMauro Carvalho Chehab switch (core->tvaudio) {
164b285192aSMauro Carvalho Chehab case WW_BG:
165b285192aSMauro Carvalho Chehab case WW_DK:
166b285192aSMauro Carvalho Chehab carrier_freq = FREQ_A2_CARRIER;
167b285192aSMauro Carvalho Chehab stereo_freq = FREQ_A2_STEREO;
168b285192aSMauro Carvalho Chehab dual_freq = FREQ_A2_DUAL;
169b285192aSMauro Carvalho Chehab break;
170b285192aSMauro Carvalho Chehab case WW_M:
171b285192aSMauro Carvalho Chehab carrier_freq = FREQ_A2M_CARRIER;
172b285192aSMauro Carvalho Chehab stereo_freq = FREQ_A2M_STEREO;
173b285192aSMauro Carvalho Chehab dual_freq = FREQ_A2M_DUAL;
174b285192aSMauro Carvalho Chehab break;
175b285192aSMauro Carvalho Chehab case WW_EIAJ:
176b285192aSMauro Carvalho Chehab carrier_freq = FREQ_EIAJ_CARRIER;
177b285192aSMauro Carvalho Chehab stereo_freq = FREQ_EIAJ_STEREO;
178b285192aSMauro Carvalho Chehab dual_freq = FREQ_EIAJ_DUAL;
179b285192aSMauro Carvalho Chehab break;
180b285192aSMauro Carvalho Chehab default:
18165bc2fe8SMauro Carvalho Chehab pr_warn("unsupported audio mode %d for %s\n",
18265bc2fe8SMauro Carvalho Chehab core->tvaudio, __func__);
183b285192aSMauro Carvalho Chehab return UNSET;
184b285192aSMauro Carvalho Chehab }
185b285192aSMauro Carvalho Chehab
186b285192aSMauro Carvalho Chehab carrier = freq_magnitude(x, N, carrier_freq);
187b285192aSMauro Carvalho Chehab stereo = freq_magnitude(x, N, stereo_freq);
188b285192aSMauro Carvalho Chehab dual = freq_magnitude(x, N, dual_freq);
189b285192aSMauro Carvalho Chehab noise = noise_magnitude(x, N, FREQ_NOISE_START, FREQ_NOISE_END);
190b285192aSMauro Carvalho Chehab
191399426caSMauro Carvalho Chehab dprintk(1,
192399426caSMauro Carvalho Chehab "detect a2/a2m/eiaj: carrier=%d, stereo=%d, dual=%d, noise=%d\n",
193e318e584SMauro Carvalho Chehab carrier, stereo, dual, noise);
194b285192aSMauro Carvalho Chehab
195b285192aSMauro Carvalho Chehab if (stereo > dual)
196b285192aSMauro Carvalho Chehab ret = V4L2_TUNER_SUB_STEREO;
197b285192aSMauro Carvalho Chehab else
198b285192aSMauro Carvalho Chehab ret = V4L2_TUNER_SUB_LANG1 | V4L2_TUNER_SUB_LANG2;
199b285192aSMauro Carvalho Chehab
200b285192aSMauro Carvalho Chehab if (core->tvaudio == WW_EIAJ) {
201b285192aSMauro Carvalho Chehab /* EIAJ checks may need adjustments */
202b285192aSMauro Carvalho Chehab if ((carrier > max(stereo, dual) * 2) &&
203b285192aSMauro Carvalho Chehab (carrier < max(stereo, dual) * 6) &&
204b285192aSMauro Carvalho Chehab (carrier > 20 && carrier < 200) &&
205b285192aSMauro Carvalho Chehab (max(stereo, dual) > min(stereo, dual))) {
206399426caSMauro Carvalho Chehab /*
207399426caSMauro Carvalho Chehab * For EIAJ the carrier is always present,
208399426caSMauro Carvalho Chehab * so we probably don't need noise detection
209399426caSMauro Carvalho Chehab */
210b285192aSMauro Carvalho Chehab return ret;
211b285192aSMauro Carvalho Chehab }
212b285192aSMauro Carvalho Chehab } else {
213b285192aSMauro Carvalho Chehab if ((carrier > max(stereo, dual) * 2) &&
214b285192aSMauro Carvalho Chehab (carrier < max(stereo, dual) * 8) &&
215b285192aSMauro Carvalho Chehab (carrier > 20 && carrier < 200) &&
216b285192aSMauro Carvalho Chehab (noise < 10) &&
217b285192aSMauro Carvalho Chehab (max(stereo, dual) > min(stereo, dual) * 2)) {
218b285192aSMauro Carvalho Chehab return ret;
219b285192aSMauro Carvalho Chehab }
220b285192aSMauro Carvalho Chehab }
221b285192aSMauro Carvalho Chehab return V4L2_TUNER_SUB_MONO;
222b285192aSMauro Carvalho Chehab }
223b285192aSMauro Carvalho Chehab
detect_btsc(struct cx88_core * core,s16 x[],u32 N)224b285192aSMauro Carvalho Chehab static s32 detect_btsc(struct cx88_core *core, s16 x[], u32 N)
225b285192aSMauro Carvalho Chehab {
226b285192aSMauro Carvalho Chehab s32 sap_ref = freq_magnitude(x, N, FREQ_BTSC_SAP_REF);
227b285192aSMauro Carvalho Chehab s32 sap = freq_magnitude(x, N, FREQ_BTSC_SAP);
228b285192aSMauro Carvalho Chehab s32 dual_ref = freq_magnitude(x, N, FREQ_BTSC_DUAL_REF);
229b285192aSMauro Carvalho Chehab s32 dual = freq_magnitude(x, N, FREQ_BTSC_DUAL);
2307b61ba8fSMauro Carvalho Chehab
231e318e584SMauro Carvalho Chehab dprintk(1, "detect btsc: dual_ref=%d, dual=%d, sap_ref=%d, sap=%d\n",
232e318e584SMauro Carvalho Chehab dual_ref, dual, sap_ref, sap);
233b285192aSMauro Carvalho Chehab /* FIXME: Currently not supported */
234b285192aSMauro Carvalho Chehab return UNSET;
235b285192aSMauro Carvalho Chehab }
236b285192aSMauro Carvalho Chehab
read_rds_samples(struct cx88_core * core,u32 * N)237b285192aSMauro Carvalho Chehab static s16 *read_rds_samples(struct cx88_core *core, u32 *N)
238b285192aSMauro Carvalho Chehab {
239b285192aSMauro Carvalho Chehab const struct sram_channel *srch = &cx88_sram_channels[SRAM_CH27];
240b285192aSMauro Carvalho Chehab s16 *samples;
241b285192aSMauro Carvalho Chehab
242b285192aSMauro Carvalho Chehab unsigned int i;
243b285192aSMauro Carvalho Chehab unsigned int bpl = srch->fifo_size / AUD_RDS_LINES;
244b285192aSMauro Carvalho Chehab unsigned int spl = bpl / 4;
245b285192aSMauro Carvalho Chehab unsigned int sample_count = spl * (AUD_RDS_LINES - 1);
246b285192aSMauro Carvalho Chehab
247b285192aSMauro Carvalho Chehab u32 current_address = cx_read(srch->ptr1_reg);
248b285192aSMauro Carvalho Chehab u32 offset = (current_address - srch->fifo_start + bpl);
249b285192aSMauro Carvalho Chehab
250399426caSMauro Carvalho Chehab dprintk(1,
251399426caSMauro Carvalho Chehab "read RDS samples: current_address=%08x (offset=%08x), sample_count=%d, aud_intstat=%08x\n",
252e318e584SMauro Carvalho Chehab current_address,
253b285192aSMauro Carvalho Chehab current_address - srch->fifo_start, sample_count,
254b285192aSMauro Carvalho Chehab cx_read(MO_AUD_INTSTAT));
255045d69ceSMarkus Elfring samples = kmalloc_array(sample_count, sizeof(*samples), GFP_KERNEL);
256b285192aSMauro Carvalho Chehab if (!samples)
257b285192aSMauro Carvalho Chehab return NULL;
258b285192aSMauro Carvalho Chehab
259b285192aSMauro Carvalho Chehab *N = sample_count;
260b285192aSMauro Carvalho Chehab
261b285192aSMauro Carvalho Chehab for (i = 0; i < sample_count; i++) {
262b285192aSMauro Carvalho Chehab offset = offset % (AUD_RDS_LINES * bpl);
263b285192aSMauro Carvalho Chehab samples[i] = cx_read(srch->fifo_start + offset);
264b285192aSMauro Carvalho Chehab offset += 4;
265b285192aSMauro Carvalho Chehab }
266b285192aSMauro Carvalho Chehab
2673b0cb24fSMauro Carvalho Chehab dprintk(2, "RDS samples dump: %*ph\n", sample_count, samples);
268b285192aSMauro Carvalho Chehab
269b285192aSMauro Carvalho Chehab return samples;
270b285192aSMauro Carvalho Chehab }
271b285192aSMauro Carvalho Chehab
cx88_dsp_detect_stereo_sap(struct cx88_core * core)272b285192aSMauro Carvalho Chehab s32 cx88_dsp_detect_stereo_sap(struct cx88_core *core)
273b285192aSMauro Carvalho Chehab {
274b285192aSMauro Carvalho Chehab s16 *samples;
275b285192aSMauro Carvalho Chehab u32 N = 0;
276b285192aSMauro Carvalho Chehab s32 ret = UNSET;
277b285192aSMauro Carvalho Chehab
278b285192aSMauro Carvalho Chehab /* If audio RDS fifo is disabled, we can't read the samples */
279b285192aSMauro Carvalho Chehab if (!(cx_read(MO_AUD_DMACNTRL) & 0x04))
280b285192aSMauro Carvalho Chehab return ret;
281b285192aSMauro Carvalho Chehab if (!(cx_read(AUD_CTL) & EN_FMRADIO_EN_RDS))
282b285192aSMauro Carvalho Chehab return ret;
283b285192aSMauro Carvalho Chehab
284b285192aSMauro Carvalho Chehab /* Wait at least 500 ms after an audio standard change */
285b285192aSMauro Carvalho Chehab if (time_before(jiffies, core->last_change + msecs_to_jiffies(500)))
286b285192aSMauro Carvalho Chehab return ret;
287b285192aSMauro Carvalho Chehab
288b285192aSMauro Carvalho Chehab samples = read_rds_samples(core, &N);
289b285192aSMauro Carvalho Chehab
290b285192aSMauro Carvalho Chehab if (!samples)
291b285192aSMauro Carvalho Chehab return ret;
292b285192aSMauro Carvalho Chehab
293b285192aSMauro Carvalho Chehab switch (core->tvaudio) {
294b285192aSMauro Carvalho Chehab case WW_BG:
295b285192aSMauro Carvalho Chehab case WW_DK:
296b285192aSMauro Carvalho Chehab case WW_EIAJ:
297b285192aSMauro Carvalho Chehab case WW_M:
298b285192aSMauro Carvalho Chehab ret = detect_a2_a2m_eiaj(core, samples, N);
299b285192aSMauro Carvalho Chehab break;
300b285192aSMauro Carvalho Chehab case WW_BTSC:
301b285192aSMauro Carvalho Chehab ret = detect_btsc(core, samples, N);
302b285192aSMauro Carvalho Chehab break;
303b285192aSMauro Carvalho Chehab case WW_NONE:
304b285192aSMauro Carvalho Chehab case WW_I:
305b285192aSMauro Carvalho Chehab case WW_L:
306b285192aSMauro Carvalho Chehab case WW_I2SPT:
307b285192aSMauro Carvalho Chehab case WW_FM:
308b285192aSMauro Carvalho Chehab case WW_I2SADC:
309b285192aSMauro Carvalho Chehab break;
310b285192aSMauro Carvalho Chehab }
311b285192aSMauro Carvalho Chehab
312b285192aSMauro Carvalho Chehab kfree(samples);
313b285192aSMauro Carvalho Chehab
3147b61ba8fSMauro Carvalho Chehab if (ret != UNSET)
315b285192aSMauro Carvalho Chehab dprintk(1, "stereo/sap detection result:%s%s%s\n",
316b285192aSMauro Carvalho Chehab (ret & V4L2_TUNER_SUB_MONO) ? " mono" : "",
317b285192aSMauro Carvalho Chehab (ret & V4L2_TUNER_SUB_STEREO) ? " stereo" : "",
318b285192aSMauro Carvalho Chehab (ret & V4L2_TUNER_SUB_LANG2) ? " dual" : "");
319b285192aSMauro Carvalho Chehab
320b285192aSMauro Carvalho Chehab return ret;
321b285192aSMauro Carvalho Chehab }
322b285192aSMauro Carvalho Chehab EXPORT_SYMBOL(cx88_dsp_detect_stereo_sap);
323b285192aSMauro Carvalho Chehab
324