text: // SPDX-License-Identifier: GPL-2.0-or-later
  /*
   * bt87x.c - Brooktree Bt878/Bt879 driver for ALSA
   *
   * Copyright (c) Clemens Ladisch <clemens@ladisch.de>
   *
   * based on btaudio.c by Gerd Knorr <kraxel@bytesex.org>
   */
  
  #include <linux/init.h>
  #include <linux/interrupt.h>
  #include <linux/pci.h>
  #include <linux/slab.h>
  #include <linux/module.h>
  #include <linux/bitops.h>
  #include <linux/io.h>
  #include <sound/core.h>
  #include <sound/pcm.h>
  #include <sound/pcm_params.h>
  #include <sound/control.h>
  #include <sound/initval.h>
  
  MODULE_AUTHOR("Clemens Ladisch <clemens@ladisch.de>");
  MODULE_DESCRIPTION("Brooktree Bt87x audio driver");
  MODULE_LICENSE("GPL");
  MODULE_SUPPORTED_DEVICE("{{Brooktree,Bt878},"
  		"{Brooktree,Bt879}}");
  
  static int index[SNDRV_CARDS] = {[0 ... (SNDRV_CARDS - 1)] = -2}; /* Exclude the first card */
  static char *id[SNDRV_CARDS] = SNDRV_DEFAULT_STR;	/* ID for this card */
  static bool enable[SNDRV_CARDS] = SNDRV_DEFAULT_ENABLE_PNP;	/* Enable this card */
  static int digital_rate[SNDRV_CARDS];	/* digital input rate */
  static bool load_all;	/* allow to load the non-whitelisted cards */
  
  module_param_array(index, int, NULL, 0444);
  MODULE_PARM_DESC(index, "Index value for Bt87x soundcard");
  module_param_array(id, charp, NULL, 0444);
  MODULE_PARM_DESC(id, "ID string for Bt87x soundcard");
  module_param_array(enable, bool, NULL, 0444);
  MODULE_PARM_DESC(enable, "Enable Bt87x soundcard");
  module_param_array(digital_rate, int, NULL, 0444);
  MODULE_PARM_DESC(digital_rate, "Digital input rate for Bt87x soundcard");
  module_param(load_all, bool, 0444);
  MODULE_PARM_DESC(load_all, "Allow to load the non-whitelisted cards");
  
  
  /* register offsets */
  #define REG_INT_STAT		0x100	/* interrupt status */
  #define REG_INT_MASK		0x104	/* interrupt mask */
  #define REG_GPIO_DMA_CTL	0x10c	/* audio control */
  #define REG_PACKET_LEN		0x110	/* audio packet lengths */
  #define REG_RISC_STRT_ADD	0x114	/* RISC program start address */
  #define REG_RISC_COUNT		0x120	/* RISC program counter */
  
  /* interrupt bits */
  #define INT_OFLOW	(1 <<  3)	/* audio A/D overflow */
  #define INT_RISCI	(1 << 11)	/* RISC instruction IRQ bit set */
  #define INT_FBUS	(1 << 12)	/* FIFO overrun due to bus access latency */
  #define INT_FTRGT	(1 << 13)	/* FIFO overrun due to target latency */
  #define INT_FDSR	(1 << 14)	/* FIFO data stream resynchronization */
  #define INT_PPERR	(1 << 15)	/* PCI parity error */
  #define INT_RIPERR	(1 << 16)	/* RISC instruction parity error */
  #define INT_PABORT	(1 << 17)	/* PCI master or target abort */
  #define INT_OCERR	(1 << 18)	/* invalid opcode */
  #define INT_SCERR	(1 << 19)	/* sync counter overflow */
  #define INT_RISC_EN	(1 << 27)	/* DMA controller running */
  #define INT_RISCS_SHIFT	      28	/* RISC status bits */
  
  /* audio control bits */
  #define CTL_FIFO_ENABLE		(1 <<  0)	/* enable audio data FIFO */
  #define CTL_RISC_ENABLE		(1 <<  1)	/* enable audio DMA controller */
  #define CTL_PKTP_4		(0 <<  2)	/* packet mode FIFO trigger point - 4 DWORDs */
  #define CTL_PKTP_8		(1 <<  2)	/* 8 DWORDs */
  #define CTL_PKTP_16		(2 <<  2)	/* 16 DWORDs */
  #define CTL_ACAP_EN		(1 <<  4)	/* enable audio capture */
  #define CTL_DA_APP		(1 <<  5)	/* GPIO input */
  #define CTL_DA_IOM_AFE		(0 <<  6)	/* audio A/D input */
  #define CTL_DA_IOM_DA		(1 <<  6)	/* digital audio input */
  #define CTL_DA_SDR_SHIFT	       8	/* DDF first stage decimation rate */
  #define CTL_DA_SDR_MASK		(0xf<< 8)
  #define CTL_DA_LMT		(1 << 12)	/* limit audio data values */
  #define CTL_DA_ES2		(1 << 13)	/* enable DDF stage 2 */
  #define CTL_DA_SBR		(1 << 14)	/* samples rounded to 8 bits */
  #define CTL_DA_DPM		(1 << 15)	/* data packet mode */
  #define CTL_DA_LRD_SHIFT	      16	/* ALRCK delay */
  #define CTL_DA_MLB		(1 << 21)	/* MSB/LSB format */
  #define CTL_DA_LRI		(1 << 22)	/* left/right indication */
  #define CTL_DA_SCE		(1 << 23)	/* sample clock edge */
  #define CTL_A_SEL_STV		(0 << 24)	/* TV tuner audio input */
  #define CTL_A_SEL_SFM		(1 << 24)	/* FM audio input */
  #define CTL_A_SEL_SML		(2 << 24)	/* mic/line audio input */
  #define CTL_A_SEL_SMXC		(3 << 24)	/* MUX bypass */
  #define CTL_A_SEL_SHIFT		      24
  #define CTL_A_SEL_MASK		(3 << 24)
  #define CTL_A_PWRDN		(1 << 26)	/* analog audio power-down */
  #define CTL_A_G2X		(1 << 27)	/* audio gain boost */
  #define CTL_A_GAIN_SHIFT	      28	/* audio input gain */
  #define CTL_A_GAIN_MASK		(0xf<<28)
  
  /* RISC instruction opcodes */
  #define RISC_WRITE	(0x1 << 28)	/* write FIFO data to memory at address */
  #define RISC_WRITEC	(0x5 << 28)	/* write FIFO data to memory at current address */
  #define RISC_SKIP	(0x2 << 28)	/* skip FIFO data */
  #define RISC_JUMP	(0x7 << 28)	/* jump to address */
  #define RISC_SYNC	(0x8 << 28)	/* synchronize with FIFO */
  
  /* RISC instruction bits */
  #define RISC_BYTES_ENABLE	(0xf << 12)	/* byte enable bits */
  #define RISC_RESYNC		(  1 << 15)	/* disable FDSR errors */
  #define RISC_SET_STATUS_SHIFT	        16	/* set status bits */
  #define RISC_RESET_STATUS_SHIFT	        20	/* clear status bits */
  #define RISC_IRQ		(  1 << 24)	/* interrupt */
  #define RISC_EOL		(  1 << 26)	/* end of line */
  #define RISC_SOL		(  1 << 27)	/* start of line */
  
  /* SYNC status bits values */
  #define RISC_SYNC_FM1	0x6
  #define RISC_SYNC_VRO	0xc
  
  #define ANALOG_CLOCK 1792000
  #ifdef CONFIG_SND_BT87X_OVERCLOCK
  #define CLOCK_DIV_MIN 1
  #else
  #define CLOCK_DIV_MIN 4
  #endif
  #define CLOCK_DIV_MAX 15
  
  #define ERROR_INTERRUPTS (INT_FBUS | INT_FTRGT | INT_PPERR | \
  			  INT_RIPERR | INT_PABORT | INT_OCERR)
  #define MY_INTERRUPTS (INT_RISCI | ERROR_INTERRUPTS)
  
  /* SYNC, one WRITE per line, one extra WRITE per page boundary, SYNC, JUMP */
  #define MAX_RISC_SIZE ((1 + 255 + (PAGE_ALIGN(255 * 4092) / PAGE_SIZE - 1) + 1 + 1) * 8)
  
  /* Cards with configuration information */
  enum snd_bt87x_boardid {
  	SND_BT87X_BOARD_UNKNOWN,
  	SND_BT87X_BOARD_GENERIC,	/* both an & dig interfaces, 32kHz */
  	SND_BT87X_BOARD_ANALOG,		/* board with no external A/D */
  	SND_BT87X_BOARD_OSPREY2x0,
  	SND_BT87X_BOARD_OSPREY440,
  	SND_BT87X_BOARD_AVPHONE98,
  };
  
  /* Card configuration */
  struct snd_bt87x_board {
  	int dig_rate;		/* Digital input sampling rate */
  	u32 digital_fmt;	/* Register settings for digital input */
  	unsigned no_analog:1;	/* No analog input */
  	unsigned no_digital:1;	/* No digital input */
  };
  
  static struct snd_bt87x_board snd_bt87x_boards[] = {
  	[SND_BT87X_BOARD_UNKNOWN] = {
  		.dig_rate = 32000, /* just a guess */
  	},
  	[SND_BT87X_BOARD_GENERIC] = {
  		.dig_rate = 32000,
  	},
  	[SND_BT87X_BOARD_ANALOG] = {
  		.no_digital = 1,
  	},
  	[SND_BT87X_BOARD_OSPREY2x0] = {
  		.dig_rate = 44100,
  		.digital_fmt = CTL_DA_LRI | (1 << CTL_DA_LRD_SHIFT),
  	},
  	[SND_BT87X_BOARD_OSPREY440] = {
  		.dig_rate = 32000,
  		.digital_fmt = CTL_DA_LRI | (1 << CTL_DA_LRD_SHIFT),
  		.no_analog = 1,
  	},
  	[SND_BT87X_BOARD_AVPHONE98] = {
  		.dig_rate = 48000,
  	},
  };
  
  struct snd_bt87x {
  	struct snd_card *card;
  	struct pci_dev *pci;
  	struct snd_bt87x_board board;
  
  	void __iomem *mmio;
  	int irq;
  
  	spinlock_t reg_lock;
  	unsigned long opened;
  	struct snd_pcm_substream *substream;
  
  	struct snd_dma_buffer dma_risc;
  	unsigned int line_bytes;
  	unsigned int lines;
  
  	u32 reg_control;
  	u32 interrupt_mask;
  
  	int current_line;
  
  	int pci_parity_errors;
  };
  
  enum { DEVICE_DIGITAL, DEVICE_ANALOG };
  
  static inline u32 snd_bt87x_readl(struct snd_bt87x *chip, u32 reg)
  {
  	return readl(chip->mmio + reg);
  }
  
  static inline void snd_bt87x_writel(struct snd_bt87x *chip, u32 reg, u32 value)
  {
  	writel(value, chip->mmio + reg);
  }
  
  static int snd_bt87x_create_risc(struct snd_bt87x *chip, struct snd_pcm_substream *substream,
  			       	 unsigned int periods, unsigned int period_bytes)
  {
  	unsigned int i, offset;
  	__le32 *risc;
  
  	if (chip->dma_risc.area == NULL) {
  		if (snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV, snd_dma_pci_data(chip->pci),
  					PAGE_ALIGN(MAX_RISC_SIZE), &chip->dma_risc) < 0)
  			return -ENOMEM;
  	}
  	risc = (__le32 *)chip->dma_risc.area;
  	offset = 0;
  	*risc++ = cpu_to_le32(RISC_SYNC | RISC_SYNC_FM1);
  	*risc++ = cpu_to_le32(0);
  	for (i = 0; i < periods; ++i) {
  		u32 rest;
  
  		rest = period_bytes;
  		do {
  			u32 cmd, len;
  			unsigned int addr;
  
  			len = PAGE_SIZE - (offset % PAGE_SIZE);
  			if (len > rest)
  				len = rest;
  			cmd = RISC_WRITE | len;
  			if (rest == period_bytes) {
  				u32 block = i * 16 / periods;
  				cmd |= RISC_SOL;
  				cmd |= block << RISC_SET_STATUS_SHIFT;
  				cmd |= (~block & 0xf) << RISC_RESET_STATUS_SHIFT;
  			}
  			if (len == rest)
  				cmd |= RISC_EOL | RISC_IRQ;
  			*risc++ = cpu_to_le32(cmd);
  			addr = snd_pcm_sgbuf_get_addr(substream, offset);
  			*risc++ = cpu_to_le32(addr);
  			offset += len;
  			rest -= len;
  		} while (rest > 0);
  	}
  	*risc++ = cpu_to_le32(RISC_SYNC | RISC_SYNC_VRO);
  	*risc++ = cpu_to_le32(0);
  	*risc++ = cpu_to_le32(RISC_JUMP);
  	*risc++ = cpu_to_le32(chip->dma_risc.addr);
  	chip->line_bytes = period_bytes;
  	chip->lines = periods;
  	return 0;
  }
  
  static void snd_bt87x_free_risc(struct snd_bt87x *chip)
  {
  	if (chip->dma_risc.area) {
  		snd_dma_free_pages(&chip->dma_risc);
  		chip->dma_risc.area = NULL;
  	}
  }
  
  static void snd_bt87x_pci_error(struct snd_bt87x *chip, unsigned int status)
  {
  	u16 pci_status;
  
  	pci_read_config_word(chip->pci, PCI_STATUS, &pci_status);
  	pci_status &= PCI_STATUS_PARITY | PCI_STATUS_SIG_TARGET_ABORT |
  		PCI_STATUS_REC_TARGET_ABORT | PCI_STATUS_REC_MASTER_ABORT |
  		PCI_STATUS_SIG_SYSTEM_ERROR | PCI_STATUS_DETECTED_PARITY;
  	pci_write_config_word(chip->pci, PCI_STATUS, pci_status);
  	if (pci_status != PCI_STATUS_DETECTED_PARITY)
  		dev_err(chip->card->dev,
  			"Aieee - PCI error! status %#08x, PCI status %#04x\n",
  			   status & ERROR_INTERRUPTS, pci_status);
  	else {
  		dev_err(chip->card->dev,
  			"Aieee - PCI parity error detected!\n");
  		/* error 'handling' similar to aic7xxx_pci.c: */
  		chip->pci_parity_errors++;
  		if (chip->pci_parity_errors > 20) {
  			dev_err(chip->card->dev,
  				"Too many PCI parity errors observed.\n");
  			dev_err(chip->card->dev,
  				"Some device on this bus is generating bad parity.\n");
  			dev_err(chip->card->dev,
  				"This is an error *observed by*, not *generated by*, this card.\n");
  			dev_err(chip->card->dev,
  				"PCI parity error checking has been disabled.\n");
  			chip->interrupt_mask &= ~(INT_PPERR | INT_RIPERR);
  			snd_bt87x_writel(chip, REG_INT_MASK, chip->interrupt_mask);
  		}
  	}
  }
  
  static irqreturn_t snd_bt87x_interrupt(int irq, void *dev_id)
  {
  	struct snd_bt87x *chip = dev_id;
  	unsigned int status, irq_status;
  
  	status = snd_bt87x_readl(chip, REG_INT_STAT);
  	irq_status = status & chip->interrupt_mask;
  	if (!irq_status)
  		return IRQ_NONE;
  	snd_bt87x_writel(chip, REG_INT_STAT, irq_status);
  
  	if (irq_status & ERROR_INTERRUPTS) {
  		if (irq_status & (INT_FBUS | INT_FTRGT))
  			dev_warn(chip->card->dev,
  				 "FIFO overrun, status %#08x\n", status);
  		if (irq_status & INT_OCERR)
  			dev_err(chip->card->dev,
  				"internal RISC error, status %#08x\n", status);
  		if (irq_status & (INT_PPERR | INT_RIPERR | INT_PABORT))
  			snd_bt87x_pci_error(chip, irq_status);
  	}
  	if ((irq_status & INT_RISCI) && (chip->reg_control & CTL_ACAP_EN)) {
  		int current_block, irq_block;
  
  		/* assume that exactly one line has been recorded */
  		chip->current_line = (chip->current_line + 1) % chip->lines;
  		/* but check if some interrupts have been skipped */
  		current_block = chip->current_line * 16 / chip->lines;
  		irq_block = status >> INT_RISCS_SHIFT;
  		if (current_block != irq_block)
  			chip->current_line = (irq_block * chip->lines + 15) / 16;
  
  		snd_pcm_period_elapsed(chip->substream);
  	}
  	return IRQ_HANDLED;
  }
  
  static const struct snd_pcm_hardware snd_bt87x_digital_hw = {
  	.info = SNDRV_PCM_INFO_MMAP |
  		SNDRV_PCM_INFO_INTERLEAVED |
  		SNDRV_PCM_INFO_BLOCK_TRANSFER |
  		SNDRV_PCM_INFO_MMAP_VALID |
  		SNDRV_PCM_INFO_BATCH,
  	.formats = SNDRV_PCM_FMTBIT_S16_LE,
  	.rates = 0, /* set at runtime */
  	.channels_min = 2,
  	.channels_max = 2,
  	.buffer_bytes_max = 255 * 4092,
  	.period_bytes_min = 32,
  	.period_bytes_max = 4092,
  	.periods_min = 2,
  	.periods_max = 255,
  };
  
  static const struct snd_pcm_hardware snd_bt87x_analog_hw = {
  	.info = SNDRV_PCM_INFO_MMAP |
  		SNDRV_PCM_INFO_INTERLEAVED |
  		SNDRV_PCM_INFO_BLOCK_TRANSFER |
  		SNDRV_PCM_INFO_MMAP_VALID |
  		SNDRV_PCM_INFO_BATCH,
  	.formats = SNDRV_PCM_FMTBIT_S16_LE | SNDRV_PCM_FMTBIT_S8,
  	.rates = SNDRV_PCM_RATE_KNOT,
  	.rate_min = ANALOG_CLOCK / CLOCK_DIV_MAX,
  	.rate_max = ANALOG_CLOCK / CLOCK_DIV_MIN,
  	.channels_min = 1,
  	.channels_max = 1,
  	.buffer_bytes_max = 255 * 4092,
  	.period_bytes_min = 32,
  	.period_bytes_max = 4092,
  	.periods_min = 2,
  	.periods_max = 255,
  };
  
  static int snd_bt87x_set_digital_hw(struct snd_bt87x *chip, struct snd_pcm_runtime *runtime)
  {
  	chip->reg_control |= CTL_DA_IOM_DA | CTL_A_PWRDN;
  	runtime->hw = snd_bt87x_digital_hw;
  	runtime->hw.rates = snd_pcm_rate_to_rate_bit(chip->board.dig_rate);
  	runtime->hw.rate_min = chip->board.dig_rate;
  	runtime->hw.rate_max = chip->board.dig_rate;
  	return 0;
  }
  
  static int snd_bt87x_set_analog_hw(struct snd_bt87x *chip, struct snd_pcm_runtime *runtime)
  {
  	static const struct snd_ratnum analog_clock = {
  		.num = ANALOG_CLOCK,
  		.den_min = CLOCK_DIV_MIN,
  		.den_max = CLOCK_DIV_MAX,
  		.den_step = 1
  	};
  	static const struct snd_pcm_hw_constraint_ratnums constraint_rates = {
  		.nrats = 1,
  		.rats = &analog_clock
  	};
  
  	chip->reg_control &= ~(CTL_DA_IOM_DA | CTL_A_PWRDN);
  	runtime->hw = snd_bt87x_analog_hw;
  	return snd_pcm_hw_constraint_ratnums(runtime, 0, SNDRV_PCM_HW_PARAM_RATE,
  					     &constraint_rates);
  }
  
  static int snd_bt87x_pcm_open(struct snd_pcm_substream *substream)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	int err;
  
  	if (test_and_set_bit(0, &chip->opened))
  		return -EBUSY;
  
  	if (substream->pcm->device == DEVICE_DIGITAL)
  		err = snd_bt87x_set_digital_hw(chip, runtime);
  	else
  		err = snd_bt87x_set_analog_hw(chip, runtime);
  	if (err < 0)
  		goto _error;
  
  	err = snd_pcm_hw_constraint_integer(runtime, SNDRV_PCM_HW_PARAM_PERIODS);
  	if (err < 0)
  		goto _error;
  
  	chip->substream = substream;
  	return 0;
  
  _error:
  	clear_bit(0, &chip->opened);
  	smp_mb__after_atomic();
  	return err;
  }
  
  static int snd_bt87x_close(struct snd_pcm_substream *substream)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  
  	spin_lock_irq(&chip->reg_lock);
  	chip->reg_control |= CTL_A_PWRDN;
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	spin_unlock_irq(&chip->reg_lock);
  
  	chip->substream = NULL;
  	clear_bit(0, &chip->opened);
  	smp_mb__after_atomic();
  	return 0;
  }
  
  static int snd_bt87x_hw_params(struct snd_pcm_substream *substream,
  			       struct snd_pcm_hw_params *hw_params)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  	int err;
  
  	err = snd_pcm_lib_malloc_pages(substream,
  				       params_buffer_bytes(hw_params));
  	if (err < 0)
  		return err;
  	return snd_bt87x_create_risc(chip, substream,
  				     params_periods(hw_params),
  				     params_period_bytes(hw_params));
  }
  
  static int snd_bt87x_hw_free(struct snd_pcm_substream *substream)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  
  	snd_bt87x_free_risc(chip);
  	snd_pcm_lib_free_pages(substream);
  	return 0;
  }
  
  static int snd_bt87x_prepare(struct snd_pcm_substream *substream)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  	struct snd_pcm_runtime *runtime = substream->runtime;
  	int decimation;
  
  	spin_lock_irq(&chip->reg_lock);
  	chip->reg_control &= ~(CTL_DA_SDR_MASK | CTL_DA_SBR);
  	decimation = (ANALOG_CLOCK + runtime->rate / 4) / runtime->rate;
  	chip->reg_control |= decimation << CTL_DA_SDR_SHIFT;
  	if (runtime->format == SNDRV_PCM_FORMAT_S8)
  		chip->reg_control |= CTL_DA_SBR;
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	spin_unlock_irq(&chip->reg_lock);
  	return 0;
  }
  
  static int snd_bt87x_start(struct snd_bt87x *chip)
  {
  	spin_lock(&chip->reg_lock);
  	chip->current_line = 0;
  	chip->reg_control |= CTL_FIFO_ENABLE | CTL_RISC_ENABLE | CTL_ACAP_EN;
  	snd_bt87x_writel(chip, REG_RISC_STRT_ADD, chip->dma_risc.addr);
  	snd_bt87x_writel(chip, REG_PACKET_LEN,
  			 chip->line_bytes | (chip->lines << 16));
  	snd_bt87x_writel(chip, REG_INT_MASK, chip->interrupt_mask);
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	spin_unlock(&chip->reg_lock);
  	return 0;
  }
  
  static int snd_bt87x_stop(struct snd_bt87x *chip)
  {
  	spin_lock(&chip->reg_lock);
  	chip->reg_control &= ~(CTL_FIFO_ENABLE | CTL_RISC_ENABLE | CTL_ACAP_EN);
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	snd_bt87x_writel(chip, REG_INT_MASK, 0);
  	snd_bt87x_writel(chip, REG_INT_STAT, MY_INTERRUPTS);
  	spin_unlock(&chip->reg_lock);
  	return 0;
  }
  
  static int snd_bt87x_trigger(struct snd_pcm_substream *substream, int cmd)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  
  	switch (cmd) {
  	case SNDRV_PCM_TRIGGER_START:
  		return snd_bt87x_start(chip);
  	case SNDRV_PCM_TRIGGER_STOP:
  		return snd_bt87x_stop(chip);
  	default:
  		return -EINVAL;
  	}
  }
  
  static snd_pcm_uframes_t snd_bt87x_pointer(struct snd_pcm_substream *substream)
  {
  	struct snd_bt87x *chip = snd_pcm_substream_chip(substream);
  	struct snd_pcm_runtime *runtime = substream->runtime;
  
  	return (snd_pcm_uframes_t)bytes_to_frames(runtime, chip->current_line * chip->line_bytes);
  }
  
  static const struct snd_pcm_ops snd_bt87x_pcm_ops = {
  	.open = snd_bt87x_pcm_open,
  	.close = snd_bt87x_close,
  	.ioctl = snd_pcm_lib_ioctl,
  	.hw_params = snd_bt87x_hw_params,
  	.hw_free = snd_bt87x_hw_free,
  	.prepare = snd_bt87x_prepare,
  	.trigger = snd_bt87x_trigger,
  	.pointer = snd_bt87x_pointer,
  	.page = snd_pcm_sgbuf_ops_page,
  };
  
  static int snd_bt87x_capture_volume_info(struct snd_kcontrol *kcontrol,
  					 struct snd_ctl_elem_info *info)
  {
  	info->type = SNDRV_CTL_ELEM_TYPE_INTEGER;
  	info->count = 1;
  	info->value.integer.min = 0;
  	info->value.integer.max = 15;
  	return 0;
  }
  
  static int snd_bt87x_capture_volume_get(struct snd_kcontrol *kcontrol,
  					struct snd_ctl_elem_value *value)
  {
  	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
  
  	value->value.integer.value[0] = (chip->reg_control & CTL_A_GAIN_MASK) >> CTL_A_GAIN_SHIFT;
  	return 0;
  }
  
  static int snd_bt87x_capture_volume_put(struct snd_kcontrol *kcontrol,
  					struct snd_ctl_elem_value *value)
  {
  	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
  	u32 old_control;
  	int changed;
  
  	spin_lock_irq(&chip->reg_lock);
  	old_control = chip->reg_control;
  	chip->reg_control = (chip->reg_control & ~CTL_A_GAIN_MASK)
  		| (value->value.integer.value[0] << CTL_A_GAIN_SHIFT);
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	changed = old_control != chip->reg_control;
  	spin_unlock_irq(&chip->reg_lock);
  	return changed;
  }
  
  static const struct snd_kcontrol_new snd_bt87x_capture_volume = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Capture Volume",
  	.info = snd_bt87x_capture_volume_info,
  	.get = snd_bt87x_capture_volume_get,
  	.put = snd_bt87x_capture_volume_put,
  };
  
  #define snd_bt87x_capture_boost_info	snd_ctl_boolean_mono_info
  
  static int snd_bt87x_capture_boost_get(struct snd_kcontrol *kcontrol,
  				       struct snd_ctl_elem_value *value)
  {
  	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
  
  	value->value.integer.value[0] = !! (chip->reg_control & CTL_A_G2X);
  	return 0;
  }
  
  static int snd_bt87x_capture_boost_put(struct snd_kcontrol *kcontrol,
  				       struct snd_ctl_elem_value *value)
  {
  	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
  	u32 old_control;
  	int changed;
  
  	spin_lock_irq(&chip->reg_lock);
  	old_control = chip->reg_control;
  	chip->reg_control = (chip->reg_control & ~CTL_A_G2X)
  		| (value->value.integer.value[0] ? CTL_A_G2X : 0);
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	changed = chip->reg_control != old_control;
  	spin_unlock_irq(&chip->reg_lock);
  	return changed;
  }
  
  static const struct snd_kcontrol_new snd_bt87x_capture_boost = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Capture Boost",
  	.info = snd_bt87x_capture_boost_info,
  	.get = snd_bt87x_capture_boost_get,
  	.put = snd_bt87x_capture_boost_put,
  };
  
  static int snd_bt87x_capture_source_info(struct snd_kcontrol *kcontrol,
  					 struct snd_ctl_elem_info *info)
  {
  	static const char *const texts[3] = {"TV Tuner", "FM", "Mic/Line"};
  
  	return snd_ctl_enum_info(info, 1, 3, texts);
  }
  
  static int snd_bt87x_capture_source_get(struct snd_kcontrol *kcontrol,
  					struct snd_ctl_elem_value *value)
  {
  	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
  
  	value->value.enumerated.item[0] = (chip->reg_control & CTL_A_SEL_MASK) >> CTL_A_SEL_SHIFT;
  	return 0;
  }
  
  static int snd_bt87x_capture_source_put(struct snd_kcontrol *kcontrol,
  					struct snd_ctl_elem_value *value)
  {
  	struct snd_bt87x *chip = snd_kcontrol_chip(kcontrol);
  	u32 old_control;
  	int changed;
  
  	spin_lock_irq(&chip->reg_lock);
  	old_control = chip->reg_control;
  	chip->reg_control = (chip->reg_control & ~CTL_A_SEL_MASK)
  		| (value->value.enumerated.item[0] << CTL_A_SEL_SHIFT);
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	changed = chip->reg_control != old_control;
  	spin_unlock_irq(&chip->reg_lock);
  	return changed;
  }
  
  static const struct snd_kcontrol_new snd_bt87x_capture_source = {
  	.iface = SNDRV_CTL_ELEM_IFACE_MIXER,
  	.name = "Capture Source",
  	.info = snd_bt87x_capture_source_info,
  	.get = snd_bt87x_capture_source_get,
  	.put = snd_bt87x_capture_source_put,
  };
  
  static int snd_bt87x_free(struct snd_bt87x *chip)
  {
  	if (chip->mmio)
  		snd_bt87x_stop(chip);
  	if (chip->irq >= 0)
  		free_irq(chip->irq, chip);
  	iounmap(chip->mmio);
  	pci_release_regions(chip->pci);
  	pci_disable_device(chip->pci);
  	kfree(chip);
  	return 0;
  }
  
  static int snd_bt87x_dev_free(struct snd_device *device)
  {
  	struct snd_bt87x *chip = device->device_data;
  	return snd_bt87x_free(chip);
  }
  
  static int snd_bt87x_pcm(struct snd_bt87x *chip, int device, char *name)
  {
  	int err;
  	struct snd_pcm *pcm;
  
  	err = snd_pcm_new(chip->card, name, device, 0, 1, &pcm);
  	if (err < 0)
  		return err;
  	pcm->private_data = chip;
  	strcpy(pcm->name, name);
  	snd_pcm_set_ops(pcm, SNDRV_PCM_STREAM_CAPTURE, &snd_bt87x_pcm_ops);
  	snd_pcm_lib_preallocate_pages_for_all(pcm, SNDRV_DMA_TYPE_DEV_SG,
  					      snd_dma_pci_data(chip->pci),
  					      128 * 1024,
  					      ALIGN(255 * 4092, 1024));
  	return 0;
  }
  
  static int snd_bt87x_create(struct snd_card *card,
  			    struct pci_dev *pci,
  			    struct snd_bt87x **rchip)
  {
  	struct snd_bt87x *chip;
  	int err;
  	static struct snd_device_ops ops = {
  		.dev_free = snd_bt87x_dev_free
  	};
  
  	*rchip = NULL;
  
  	err = pci_enable_device(pci);
  	if (err < 0)
  		return err;
  
  	chip = kzalloc(sizeof(*chip), GFP_KERNEL);
  	if (!chip) {
  		pci_disable_device(pci);
  		return -ENOMEM;
  	}
  	chip->card = card;
  	chip->pci = pci;
  	chip->irq = -1;
  	spin_lock_init(&chip->reg_lock);
  
  	if ((err = pci_request_regions(pci, "Bt87x audio")) < 0) {
  		kfree(chip);
  		pci_disable_device(pci);
  		return err;
  	}
  	chip->mmio = pci_ioremap_bar(pci, 0);
  	if (!chip->mmio) {
  		dev_err(card->dev, "cannot remap io memory\n");
  		err = -ENOMEM;
  		goto fail;
  	}
  
  	chip->reg_control = CTL_A_PWRDN | CTL_DA_ES2 |
  			    CTL_PKTP_16 | (15 << CTL_DA_SDR_SHIFT);
  	chip->interrupt_mask = MY_INTERRUPTS;
  	snd_bt87x_writel(chip, REG_GPIO_DMA_CTL, chip->reg_control);
  	snd_bt87x_writel(chip, REG_INT_MASK, 0);
  	snd_bt87x_writel(chip, REG_INT_STAT, MY_INTERRUPTS);
  
  	err = request_irq(pci->irq, snd_bt87x_interrupt, IRQF_SHARED,
  			  KBUILD_MODNAME, chip);
  	if (err < 0) {
  		dev_err(card->dev, "cannot grab irq %d\n", pci->irq);
  		goto fail;
  	}
  	chip->irq = pci->irq;
  	pci_set_master(pci);
  	synchronize_irq(chip->irq);
  
  	err = snd_device_new(card, SNDRV_DEV_LOWLEVEL, chip, &ops);
  	if (err < 0)
  		goto fail;
  
  	*rchip = chip;
  	return 0;
  
  fail:
  	snd_bt87x_free(chip);
  	return err;
  }
  
  #define BT_DEVICE(chip, subvend, subdev, id) \
  	{ .vendor = PCI_VENDOR_ID_BROOKTREE, \
  	  .device = chip, \
  	  .subvendor = subvend, .subdevice = subdev, \
  	  .driver_data = SND_BT87X_BOARD_ ## id }
  /* driver_data is the card id for that device */
  
  static const struct pci_device_id snd_bt87x_ids[] = {
  	/* Hauppauge WinTV series */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x0070, 0x13eb, GENERIC),
  	/* Hauppauge WinTV series */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_879, 0x0070, 0x13eb, GENERIC),
  	/* Viewcast Osprey 200 */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x0070, 0xff01, OSPREY2x0),
  	/* Viewcast Osprey 440 (rate is configurable via gpio) */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x0070, 0xff07, OSPREY440),
  	/* ATI TV-Wonder */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x1002, 0x0001, GENERIC),
  	/* Leadtek Winfast tv 2000xp delux */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x107d, 0x6606, GENERIC),
  	/* Pinnacle PCTV */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x11bd, 0x0012, GENERIC),
  	/* Voodoo TV 200 */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x121a, 0x3000, GENERIC),
  	/* Askey Computer Corp. MagicTView'99 */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x144f, 0x3000, GENERIC),
  	/* AVerMedia Studio No. 103, 203, ...? */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x1461, 0x0003, AVPHONE98),
  	/* Prolink PixelView PV-M4900 */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0x1554, 0x4011, GENERIC),
  	/* Pinnacle  Studio PCTV rave */
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, 0xbd11, 0x1200, GENERIC),
  	{ }
  };
  MODULE_DEVICE_TABLE(pci, snd_bt87x_ids);
  
  /* cards known not to have audio
   * (DVB cards use the audio function to transfer MPEG data) */
  static struct {
  	unsigned short subvendor, subdevice;
  } blacklist[] = {
  	{0x0071, 0x0101}, /* Nebula Electronics DigiTV */
  	{0x11bd, 0x001c}, /* Pinnacle PCTV Sat */
  	{0x11bd, 0x0026}, /* Pinnacle PCTV SAT CI */
  	{0x1461, 0x0761}, /* AVermedia AverTV DVB-T */
  	{0x1461, 0x0771}, /* AVermedia DVB-T 771 */
  	{0x1822, 0x0001}, /* Twinhan VisionPlus DVB-T */
  	{0x18ac, 0xd500}, /* DVICO FusionHDTV 5 Lite */
  	{0x18ac, 0xdb10}, /* DVICO FusionHDTV DVB-T Lite */
  	{0x18ac, 0xdb11}, /* Ultraview DVB-T Lite */
  	{0x270f, 0xfc00}, /* Chaintech Digitop DST-1000 DVB-S */
  	{0x7063, 0x2000}, /* pcHDTV HD-2000 TV */
  };
  
  static struct pci_driver driver;
  
  /* return the id of the card, or a negative value if it's blacklisted */
  static int snd_bt87x_detect_card(struct pci_dev *pci)
  {
  	int i;
  	const struct pci_device_id *supported;
  
  	supported = pci_match_id(snd_bt87x_ids, pci);
  	if (supported && supported->driver_data > 0)
  		return supported->driver_data;
  
  	for (i = 0; i < ARRAY_SIZE(blacklist); ++i)
  		if (blacklist[i].subvendor == pci->subsystem_vendor &&
  		    blacklist[i].subdevice == pci->subsystem_device) {
  			dev_dbg(&pci->dev,
  				"card %#04x-%#04x:%#04x has no audio\n",
  				    pci->device, pci->subsystem_vendor, pci->subsystem_device);
  			return -EBUSY;
  		}
  
  	dev_info(&pci->dev, "unknown card %#04x-%#04x:%#04x\n",
  		   pci->device, pci->subsystem_vendor, pci->subsystem_device);
  	dev_info(&pci->dev, "please mail id, board name, and, "
  		   "if it works, the correct digital_rate option to "
  		   "<alsa-devel@alsa-project.org>\n");
  	return SND_BT87X_BOARD_UNKNOWN;
  }
  
  static int snd_bt87x_probe(struct pci_dev *pci,
  			   const struct pci_device_id *pci_id)
  {
  	static int dev;
  	struct snd_card *card;
  	struct snd_bt87x *chip;
  	int err;
  	enum snd_bt87x_boardid boardid;
  
  	if (!pci_id->driver_data) {
  		err = snd_bt87x_detect_card(pci);
  		if (err < 0)
  			return -ENODEV;
  		boardid = err;
  	} else
  		boardid = pci_id->driver_data;
  
  	if (dev >= SNDRV_CARDS)
  		return -ENODEV;
  	if (!enable[dev]) {
  		++dev;
  		return -ENOENT;
  	}
  
  	err = snd_card_new(&pci->dev, index[dev], id[dev], THIS_MODULE,
  			   0, &card);
  	if (err < 0)
  		return err;
  
  	err = snd_bt87x_create(card, pci, &chip);
  	if (err < 0)
  		goto _error;
  
  	memcpy(&chip->board, &snd_bt87x_boards[boardid], sizeof(chip->board));
  
  	if (!chip->board.no_digital) {
  		if (digital_rate[dev] > 0)
  			chip->board.dig_rate = digital_rate[dev];
  
  		chip->reg_control |= chip->board.digital_fmt;
  
  		err = snd_bt87x_pcm(chip, DEVICE_DIGITAL, "Bt87x Digital");
  		if (err < 0)
  			goto _error;
  	}
  	if (!chip->board.no_analog) {
  		err = snd_bt87x_pcm(chip, DEVICE_ANALOG, "Bt87x Analog");
  		if (err < 0)
  			goto _error;
  		err = snd_ctl_add(card, snd_ctl_new1(
  				  &snd_bt87x_capture_volume, chip));
  		if (err < 0)
  			goto _error;
  		err = snd_ctl_add(card, snd_ctl_new1(
  				  &snd_bt87x_capture_boost, chip));
  		if (err < 0)
  			goto _error;
  		err = snd_ctl_add(card, snd_ctl_new1(
  				  &snd_bt87x_capture_source, chip));
  		if (err < 0)
  			goto _error;
  	}
  	dev_info(card->dev, "bt87x%d: Using board %d, %sanalog, %sdigital "
  		   "(rate %d Hz)\n", dev, boardid,
  		   chip->board.no_analog ? "no " : "",
  		   chip->board.no_digital ? "no " : "", chip->board.dig_rate);
  
  	strcpy(card->driver, "Bt87x");
  	sprintf(card->shortname, "Brooktree Bt%x", pci->device);
  	sprintf(card->longname, "%s at %#llx, irq %i",
  		card->shortname, (unsigned long long)pci_resource_start(pci, 0),
  		chip->irq);
  	strcpy(card->mixername, "Bt87x");
  
  	err = snd_card_register(card);
  	if (err < 0)
  		goto _error;
  
  	pci_set_drvdata(pci, card);
  	++dev;
  	return 0;
  
  _error:
  	snd_card_free(card);
  	return err;
  }
  
  static void snd_bt87x_remove(struct pci_dev *pci)
  {
  	snd_card_free(pci_get_drvdata(pci));
  }
  
  /* default entries for all Bt87x cards - it's not exported */
  /* driver_data is set to 0 to call detection */
  static const struct pci_device_id snd_bt87x_default_ids[] = {
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_878, PCI_ANY_ID, PCI_ANY_ID, UNKNOWN),
  	BT_DEVICE(PCI_DEVICE_ID_BROOKTREE_879, PCI_ANY_ID, PCI_ANY_ID, UNKNOWN),
  	{ }
  };
  
  static struct pci_driver driver = {
  	.name = KBUILD_MODNAME,
  	.id_table = snd_bt87x_ids,
  	.probe = snd_bt87x_probe,
  	.remove = snd_bt87x_remove,
  };
  
  static int __init alsa_card_bt87x_init(void)
  {
  	if (load_all)
  		driver.id_table = snd_bt87x_default_ids;
  	return pci_register_driver(&driver);
  }
  
  static void __exit alsa_card_bt87x_exit(void)
  {
  	pci_unregister_driver(&driver);
  }
  
  module_init(alsa_card_bt87x_init)
  module_exit(alsa_card_bt87x_exit)
  