📄 dmasound_paula.c
字号:
/* * linux/sound/oss/dmasound/dmasound_paula.c * * Amiga `Paula' DMA Sound Driver * * See linux/sound/oss/dmasound/dmasound_core.c for copyright and credits * prior to 28/01/2001 * * 28/01/2001 [0.1] Iain Sandoe * - added versioning * - put in and populated the hardware_afmts field. * [0.2] - put in SNDCTL_DSP_GETCAPS value. * [0.3] - put in constraint on state buffer usage. * [0.4] - put in default hard/soft settings*/#include <linux/module.h>#include <linux/config.h>#include <linux/mm.h>#include <linux/init.h>#include <linux/ioport.h>#include <linux/soundcard.h>#include <linux/interrupt.h>#include <asm/uaccess.h>#include <asm/setup.h>#include <asm/amigahw.h>#include <asm/amigaints.h>#include <asm/machdep.h>#include "dmasound.h"#define DMASOUND_PAULA_REVISION 0#define DMASOUND_PAULA_EDITION 4 /* * The minimum period for audio depends on htotal (for OCS/ECS/AGA) * (Imported from arch/m68k/amiga/amisound.c) */extern volatile u_short amiga_audio_min_period; /* * amiga_mksound() should be able to restore the period after beeping * (Imported from arch/m68k/amiga/amisound.c) */extern u_short amiga_audio_period; /* * Audio DMA masks */#define AMI_AUDIO_OFF (DMAF_AUD0 | DMAF_AUD1 | DMAF_AUD2 | DMAF_AUD3)#define AMI_AUDIO_8 (DMAF_SETCLR | DMAF_MASTER | DMAF_AUD0 | DMAF_AUD1)#define AMI_AUDIO_14 (AMI_AUDIO_8 | DMAF_AUD2 | DMAF_AUD3) /* * Helper pointers for 16(14)-bit sound */static int write_sq_block_size_half, write_sq_block_size_quarter;/*** Low level stuff *********************************************************/static void *AmiAlloc(unsigned int size, gfp_t flags);static void AmiFree(void *obj, unsigned int size);static int AmiIrqInit(void);#ifdef MODULEstatic void AmiIrqCleanUp(void);#endifstatic void AmiSilence(void);static void AmiInit(void);static int AmiSetFormat(int format);static int AmiSetVolume(int volume);static int AmiSetTreble(int treble);static void AmiPlayNextFrame(int index);static void AmiPlay(void);static irqreturn_t AmiInterrupt(int irq, void *dummy, struct pt_regs *fp);#ifdef CONFIG_HEARTBEAT /* * Heartbeat interferes with sound since the 7 kHz low-pass filter and the * power LED are controlled by the same line. */#ifdef CONFIG_APUS#define mach_heartbeat ppc_md.heartbeat#endifstatic void (*saved_heartbeat)(int) = NULL;static inline void disable_heartbeat(void){ if (mach_heartbeat) { saved_heartbeat = mach_heartbeat; mach_heartbeat = NULL; } AmiSetTreble(dmasound.treble);}static inline void enable_heartbeat(void){ if (saved_heartbeat) mach_heartbeat = saved_heartbeat;}#else /* !CONFIG_HEARTBEAT */#define disable_heartbeat() do { } while (0)#define enable_heartbeat() do { } while (0)#endif /* !CONFIG_HEARTBEAT *//*** Mid level stuff *********************************************************/static void AmiMixerInit(void);static int AmiMixerIoctl(u_int cmd, u_long arg);static int AmiWriteSqSetup(void);static int AmiStateInfo(char *buffer, size_t space);/*** Translations ************************************************************//* ++TeSche: radically changed for new expanding purposes... * * These two routines now deal with copying/expanding/translating the samples * from user space into our buffer at the right frequency. They take care about * how much data there's actually to read, how much buffer space there is and * to convert samples into the right frequency/encoding. They will only work on * complete samples so it may happen they leave some bytes in the input stream * if the user didn't write a multiple of the current sample size. They both * return the number of bytes they've used from both streams so you may detect * such a situation. Luckily all programs should be able to cope with that. * * I think I've optimized anything as far as one can do in plain C, all * variables should fit in registers and the loops are really short. There's * one loop for every possible situation. Writing a more generalized and thus * parameterized loop would only produce slower code. Feel free to optimize * this in assembler if you like. :) * * I think these routines belong here because they're not yet really hardware * independent, especially the fact that the Falcon can play 16bit samples * only in stereo is hardcoded in both of them! * * ++geert: split in even more functions (one per format) */ /* * Native format */static ssize_t ami_ct_s8(const u_char *userPtr, size_t userCount, u_char frame[], ssize_t *frameUsed, ssize_t frameLeft){ ssize_t count, used; if (!dmasound.soft.stereo) { void *p = &frame[*frameUsed]; count = min_t(unsigned long, userCount, frameLeft) & ~1; used = count; if (copy_from_user(p, userPtr, count)) return -EFAULT; } else { u_char *left = &frame[*frameUsed>>1]; u_char *right = left+write_sq_block_size_half; count = min_t(unsigned long, userCount, frameLeft)>>1 & ~1; used = count*2; while (count > 0) { if (get_user(*left++, userPtr++) || get_user(*right++, userPtr++)) return -EFAULT; count--; } } *frameUsed += used; return used;} /* * Copy and convert 8 bit data */#define GENERATE_AMI_CT8(funcname, convsample) \static ssize_t funcname(const u_char *userPtr, size_t userCount, \ u_char frame[], ssize_t *frameUsed, \ ssize_t frameLeft) \{ \ ssize_t count, used; \ \ if (!dmasound.soft.stereo) { \ u_char *p = &frame[*frameUsed]; \ count = min_t(size_t, userCount, frameLeft) & ~1; \ used = count; \ while (count > 0) { \ u_char data; \ if (get_user(data, userPtr++)) \ return -EFAULT; \ *p++ = convsample(data); \ count--; \ } \ } else { \ u_char *left = &frame[*frameUsed>>1]; \ u_char *right = left+write_sq_block_size_half; \ count = min_t(size_t, userCount, frameLeft)>>1 & ~1; \ used = count*2; \ while (count > 0) { \ u_char data; \ if (get_user(data, userPtr++)) \ return -EFAULT; \ *left++ = convsample(data); \ if (get_user(data, userPtr++)) \ return -EFAULT; \ *right++ = convsample(data); \ count--; \ } \ } \ *frameUsed += used; \ return used; \}#define AMI_CT_ULAW(x) (dmasound_ulaw2dma8[(x)])#define AMI_CT_ALAW(x) (dmasound_alaw2dma8[(x)])#define AMI_CT_U8(x) ((x) ^ 0x80)GENERATE_AMI_CT8(ami_ct_ulaw, AMI_CT_ULAW)GENERATE_AMI_CT8(ami_ct_alaw, AMI_CT_ALAW)GENERATE_AMI_CT8(ami_ct_u8, AMI_CT_U8) /* * Copy and convert 16 bit data */#define GENERATE_AMI_CT_16(funcname, convsample) \static ssize_t funcname(const u_char *userPtr, size_t userCount, \ u_char frame[], ssize_t *frameUsed, \ ssize_t frameLeft) \{ \ ssize_t count, used; \ u_short data; \ \ if (!dmasound.soft.stereo) { \ u_char *high = &frame[*frameUsed>>1]; \ u_char *low = high+write_sq_block_size_half; \ count = min_t(size_t, userCount, frameLeft)>>1 & ~1; \ used = count*2; \ while (count > 0) { \ if (get_user(data, ((u_short *)userPtr)++)) \ return -EFAULT; \ data = convsample(data); \ *high++ = data>>8; \ *low++ = (data>>2) & 0x3f; \ count--; \ } \ } else { \ u_char *lefth = &frame[*frameUsed>>2]; \ u_char *leftl = lefth+write_sq_block_size_quarter; \ u_char *righth = lefth+write_sq_block_size_half; \ u_char *rightl = righth+write_sq_block_size_quarter; \ count = min_t(size_t, userCount, frameLeft)>>2 & ~1; \ used = count*4; \ while (count > 0) { \ if (get_user(data, ((u_short *)userPtr)++)) \ return -EFAULT; \ data = convsample(data); \ *lefth++ = data>>8; \ *leftl++ = (data>>2) & 0x3f; \ if (get_user(data, ((u_short *)userPtr)++)) \ return -EFAULT; \ data = convsample(data); \ *righth++ = data>>8; \ *rightl++ = (data>>2) & 0x3f; \ count--; \ } \ } \ *frameUsed += used; \ return used; \}#define AMI_CT_S16BE(x) (x)#define AMI_CT_U16BE(x) ((x) ^ 0x8000)#define AMI_CT_S16LE(x) (le2be16((x)))#define AMI_CT_U16LE(x) (le2be16((x)) ^ 0x8000)GENERATE_AMI_CT_16(ami_ct_s16be, AMI_CT_S16BE)GENERATE_AMI_CT_16(ami_ct_u16be, AMI_CT_U16BE)GENERATE_AMI_CT_16(ami_ct_s16le, AMI_CT_S16LE)GENERATE_AMI_CT_16(ami_ct_u16le, AMI_CT_U16LE)static TRANS transAmiga = { .ct_ulaw = ami_ct_ulaw, .ct_alaw = ami_ct_alaw, .ct_s8 = ami_ct_s8, .ct_u8 = ami_ct_u8, .ct_s16be = ami_ct_s16be, .ct_u16be = ami_ct_u16be, .ct_s16le = ami_ct_s16le, .ct_u16le = ami_ct_u16le,};/*** Low level stuff *********************************************************/static inline void StopDMA(void){ custom.aud[0].audvol = custom.aud[1].audvol = 0; custom.aud[2].audvol = custom.aud[3].audvol = 0; custom.dmacon = AMI_AUDIO_OFF; enable_heartbeat();}static void *AmiAlloc(unsigned int size, gfp_t flags){ return amiga_chip_alloc((long)size, "dmasound [Paula]");}static void AmiFree(void *obj, unsigned int size){ amiga_chip_free (obj);}static int __init AmiIrqInit(void){ /* turn off DMA for audio channels */ StopDMA(); /* Register interrupt handler. */ if (request_irq(IRQ_AMIGA_AUD0, AmiInterrupt, 0, "DMA sound", AmiInterrupt)) return 0; return 1;}#ifdef MODULEstatic void AmiIrqCleanUp(void){ /* turn off DMA for audio channels */ StopDMA(); /* release the interrupt */ free_irq(IRQ_AMIGA_AUD0, AmiInterrupt);}#endif /* MODULE */static void AmiSilence(void){ /* turn off DMA for audio channels */ StopDMA();}static void AmiInit(void){ int period, i; AmiSilence(); if (dmasound.soft.speed) period = amiga_colorclock/dmasound.soft.speed-1; else period = amiga_audio_min_period; dmasound.hard = dmasound.soft; dmasound.trans_write = &transAmiga; if (period < amiga_audio_min_period) {
⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -