Hi Nicolin, Am Montag, den 05.08.2013, 15:29 +0800 schrieb Nicolin Chen: > This patch add S/PDIF controller driver for Freescale SoC. > > Signed-off-by: Nicolin Chen <b42378@xxxxxxxxxxxxx> > --- > .../devicetree/bindings/sound/fsl,spdif.txt | 62 + > sound/soc/fsl/Kconfig | 3 + > sound/soc/fsl/Makefile | 2 + > sound/soc/fsl/fsl_spdif.c | 1311 ++++++++++++++++++++ > sound/soc/fsl/fsl_spdif.h | 227 ++++ > 5 files changed, 1605 insertions(+), 0 deletions(-) > create mode 100644 Documentation/devicetree/bindings/sound/fsl,spdif.txt > create mode 100644 sound/soc/fsl/fsl_spdif.c > create mode 100644 sound/soc/fsl/fsl_spdif.h > > diff --git a/Documentation/devicetree/bindings/sound/fsl,spdif.txt b/Documentation/devicetree/bindings/sound/fsl,spdif.txt > new file mode 100644 > index 0000000..8b1bfe2 > --- /dev/null > +++ b/Documentation/devicetree/bindings/sound/fsl,spdif.txt > @@ -0,0 +1,62 @@ > +Freescale Sony/Philips Digital Interface Format (S/PDIF) Controller > + > +The Freescale S/PDIF audio block is a stereo transceiver that allows the > +processor to receive and transmit digital audio via an coaxial cable or > +a fibre cable. > + > +Required properties: > + > + - compatible : Compatible list, contains "fsl,fsl-spdif" or SoC specific > + "fsl,imx6q-spdif", "fsl,imx6sl-spdif". i.MX53 also has this S/PDIF block. > + - reg : Offset and length of the register set for the device. > + > + - interrupts : Should contain spdif interrupt. > + > + - dmas : Generic dma devicetree binding as described in > + Documentation/devicetree/bindings/dma/dma.txt. > + > + - dma-names : Two dmas have to be defined, "tx" and "rx". > + > + - clocks : (First) The phandle for the clock ID registered in clock tree. > + There could be two clocks being set here, but only the first one, CORE > + clock, is must. > + > + > +Optional properties: > + > + - clocks : (Second) The phandle for the clock ID registered in clock tree. > + There could be two clocks being set here, but the second one, TX clock is > + optional. If absent, the TX clock will use CORE clock as default. > + > + - clock-names : The names for the two clocks. It will be required only when > + the second clock's present. If absent, the TX clock will use CORE clock as > + default. > + > + - tx-clk-source : The clock cources for Tx. Need to set this source according > + to the SoC datasheet in SPDIF_STC section. If absent, the default source is > + value 0x1 - CCM spdif0_clk_root input. >+ > + - rx-clk-source : The clock cource for Rx. Need to set this source according > + to the SoC datasheet in SPDIF_SRPC section. If absent, the default source is > + value 0x0 - if (DPLL Locked) SPDIF_RxClk else extal. This looks to me like a case of configuration data in the device tree. Couldn't the tx/rx clock source be determined automatically or at least the SoC specific clock sources to the mux be known to the driver, so that we can use clock phandles here? What happens if a different tx-clk-source is needed for 48 kHz than for 44.1 kHz? > +Example: > + > +spdif: spdif@02004000 { > + compatible = "fsl,fsl-spdif"; > + reg = <0x02004000 0x4000>; > + interrupts = <0 52 0x04>; > + dmas = <&sdma 14 18 0>, > + <&sdma 15 18 0>; > + dma-names = "rx", "tx"; > + > + clocks = <&clks 197>, <&clks 197>; > + clock-names = "core", "tx"; > + > + tx-clk-source = <0x1>; > + rx-clk-source = <0x0>; > + > + status = "okay"; > +}; > diff --git a/sound/soc/fsl/Kconfig b/sound/soc/fsl/Kconfig > index c26449b..74f533b 100644 > --- a/sound/soc/fsl/Kconfig > +++ b/sound/soc/fsl/Kconfig > @@ -1,6 +1,9 @@ > config SND_SOC_FSL_SSI > tristate > > +config SND_SOC_FSL_SPDIF > + tristate > + > config SND_SOC_FSL_UTILS > tristate > > diff --git a/sound/soc/fsl/Makefile b/sound/soc/fsl/Makefile > index d4b4aa8..4b5970e 100644 > --- a/sound/soc/fsl/Makefile > +++ b/sound/soc/fsl/Makefile > @@ -12,9 +12,11 @@ obj-$(CONFIG_SND_SOC_P1022_RDK) += snd-soc-p1022-rdk.o > > # Freescale PowerPC SSI/DMA Platform Support > snd-soc-fsl-ssi-objs := fsl_ssi.o > +snd-soc-fsl-spdif-objs := fsl_spdif.o > snd-soc-fsl-utils-objs := fsl_utils.o > snd-soc-fsl-dma-objs := fsl_dma.o > obj-$(CONFIG_SND_SOC_FSL_SSI) += snd-soc-fsl-ssi.o > +obj-$(CONFIG_SND_SOC_FSL_SPDIF) += snd-soc-fsl-spdif.o > obj-$(CONFIG_SND_SOC_FSL_UTILS) += snd-soc-fsl-utils.o > obj-$(CONFIG_SND_SOC_POWERPC_DMA) += snd-soc-fsl-dma.o > > diff --git a/sound/soc/fsl/fsl_spdif.c b/sound/soc/fsl/fsl_spdif.c > new file mode 100644 > index 0000000..8865499 > --- /dev/null > +++ b/sound/soc/fsl/fsl_spdif.c > @@ -0,0 +1,1311 @@ > +/* > + * Freescale S/PDIF ALSA SoC Digital Audio Interface (DAI) driver > + * > + * Copyright (C) 2013 Freescale Semiconductor, Inc. > + * > + * Based on stmp3xxx_spdif_dai.c > + * Vladimir Barinov <vbarinov@xxxxxxxxxxxxxxxxx> > + * Copyright 2008 SigmaTel, Inc > + * Copyright 2008 Embedded Alley Solutions, Inc > + * > + * This file is licensed under the terms of the GNU General Public License > + * version 2. This program is licensed "as is" without any warranty of any > + * kind, whether express or implied. > + */ > + > +#include <linux/module.h> > +#include <linux/clk.h> > +#include <linux/of_address.h> > +#include <linux/of_device.h> > +#include <linux/of_irq.h> > + > +#include <sound/asoundef.h> > +#include <sound/soc.h> > +#include <sound/dmaengine_pcm.h> > + > +#include "fsl_spdif.h" > +#include "imx-pcm.h" > + > +#define FSL_SPDIF_TXFIFO_WML 0x8 > +#define FSL_SPDIF_RXFIFO_WML 0x8 > + > +#define INTR_FOR_PLAYBACK (INT_TXFIFO_RESYNC) > +#define INTR_FOR_CAPTURE (INT_SYM_ERR | INT_BIT_ERR | INT_URX_FUL | INT_URX_OV|\ > + INT_QRX_FUL | INT_QRX_OV | INT_UQ_SYNC | INT_UQ_ERR |\ > + INT_RXFIFO_RESYNC | INT_LOSS_LOCK | INT_DPLL_LOCKED) > + > +enum fsl_spdif_type { > + FSL_IMX6Q_SPDIF, > + FSL_IMX6SL_SPDIF, > +}; > + > +static struct platform_device_id fsl_spdif_devtype[] = { > + { > + .name = "imx6q-spdif", > + .driver_data = FSL_IMX6Q_SPDIF, > + }, > + { > + .name = "imx6sl-spdif", > + .driver_data = FSL_IMX6SL_SPDIF, > + }, > +}; > +MODULE_DEVICE_TABLE(platform, fsl_spdif_devtype); > + > +static const struct of_device_id fsl_spdif_dt_ids[] = { > + { .compatible = "fsl,fsl-spdif", .data = &fsl_spdif_devtype[FSL_IMX6Q_SPDIF], }, > + { .compatible = "fsl,imx6q-spdif", .data = &fsl_spdif_devtype[FSL_IMX6Q_SPDIF], }, > + { .compatible = "fsl,imx6dl-spdif", .data = &fsl_spdif_devtype[FSL_IMX6Q_SPDIF], }, > + { .compatible = "fsl,imx6sl-spdif", .data = &fsl_spdif_devtype[FSL_IMX6SL_SPDIF], }, > + {} > +}; > +MODULE_DEVICE_TABLE(of, fsl_spdif_dt_ids); As there is no difference between imx6q and imx6dl, I think they should use the same compatible string. > + > +/* spdif_devtype indicates which module version is being used */ > +static u8 spdif_devtype; > + > +/* > + * SPDIF control structure > + * Defines channel status, subcode and Q sub > + */ > +struct spdif_mixer_control { > + /* spinlock to access control data */ > + spinlock_t ctl_lock; > + > + /* IEC958 channel tx status bit */ > + unsigned char ch_status[4]; > + > + /* User bits */ > + unsigned char subcode[2 * SPDIF_UBITS_SIZE]; > + > + /* Q subcode part of user bits */ > + unsigned char qsub[2 * SPDIF_QSUB_SIZE]; > + > + /* buffer ptrs for writer */ > + u32 upos; > + u32 qpos; > + > + /* ready buffer index of the two buffers */ > + u32 ready_buf; > +}; > + > +struct fsl_spdif_priv { > + struct spdif_mixer_control fsl_spdif_control; > + struct snd_soc_dai_driver cpu_dai_drv; > + struct reg_spdif __iomem *spdif; > + struct platform_device *pdev; > + dma_addr_t spdif_phys; > + atomic_t dpll_locked; > + u32 irq; > + u8 rxclk_src; > + u8 txclk_src; > + u8 txclk_div[SPDIF_TXRATE_MAX]; > + struct clk *txclk; > + struct clk *coreclk; > + struct snd_dmaengine_dai_dma_data dma_params_tx; > + struct snd_dmaengine_dai_dma_data dma_params_rx; > + > + char name[1]; Maybe use name[0] here and add a comment to make clear that this space will be allocated dynamically? > +}; > + > + > +/* All the registers of SPDIF are 24-bit implemented */ > +static u32 spdif_read(u32 __iomem *addr) > +{ > + return __raw_readl(addr) & 0xffffff; > +} > + > +static void spdif_write(u32 __iomem *addr, u32 val) > +{ > + __raw_writel(val & 0xffffff, addr); > +} > + > +static void spdif_setbits(u32 __iomem *addr, u32 bits) > +{ > + u32 val; > + > + val = spdif_read(addr); > + val |= bits; > + spdif_write(addr, val); > +} > + > +static void spdif_clrbits(u32 __iomem *addr, u32 bits) > +{ > + u32 val; > + > + val = spdif_read(addr); > + val &= ~bits; > + spdif_write(addr, val); > +} > + > +static void spdif_setmask(u32 __iomem *addr, u32 mask, u32 bits) > +{ > + u32 val; > + > + val = spdif_read(addr); > + val = (val & ~mask) | (bits & mask); > + spdif_write(addr, val); > +} > + > +#ifdef DEBUG > +static void dumpregs(struct fsl_spdif_priv *spdif_priv) > +{ > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 val, i; > + > + clk_enable(spdif_priv->coreclk); > + > + /* Valid address set of SPDIF is {[0x0-0x38], 0x44, 0x50} */ > + for (i = 0 ; i <= 0x38 ; i += 4) { > + val = spdif_read(&spdif->scr + i / 4); > + dev_dbg(&pdev->dev, "REG 0x%02x = 0x%06x\n", i, val); > + } > + > + i = 0x44; > + val = spdif_read(&spdif->scr + i / 4) & 0xffffff; > + dev_dbg(&pdev->dev, "REG 0x%02x = 0x%06x\n", i, val); > + > + i = 0x50; > + val = spdif_read(&spdif->scr + i / 4) & 0xffffff; > + dev_dbg(&pdev->dev, "REG 0x%02x = 0x%06x\n", i, val); > + > + clk_disable(spdif_priv->coreclk); > +} > +#else > +static void dumpregs(struct fsl_spdif_priv *spdif_priv) {} > +#endif Instead of reimplementing all this, you could also use regmap, which can also take care of enabling the core clock for register access. > +/* DPLL locked and lock loss interrupt handler */ > +static void spdif_irq_dpll_lock(struct fsl_spdif_priv *spdif_priv) > +{ > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 locked = spdif_read(&spdif->srpc) & SRPC_DPLL_LOCKED; > + > + dev_dbg(&pdev->dev, "isr: Rx dpll %s \n", > + locked ? "locked" : "loss lock"); > + > + atomic_set(&spdif_priv->dpll_locked, locked ? 1 : 0); > +} > + > +/* Receiver found illegal symbol interrupt handler */ > +static void spdif_irq_sym_error(struct fsl_spdif_priv *spdif_priv) > +{ > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + > + dev_dbg(&pdev->dev, "isr: receiver found illegal symbol\n"); > + > + if (!atomic_read(&spdif_priv->dpll_locked)) { > + /* dpll unlocked seems no audio stream */ > + spdif_clrbits(&spdif->sie, INT_SYM_ERR); > + } > +} > + > +/* U/Q Channel receive register full */ > +static void spdif_irq_uqrx_full(struct fsl_spdif_priv *spdif_priv, char name) > +{ > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 *pos, size, val; > + u32 __iomem *reg; > + > + switch (name) { > + case 'U': > + pos = &ctrl->upos; > + size = SPDIF_UBITS_SIZE; > + reg = &spdif->sru; > + break; > + case 'Q': > + pos = &ctrl->qpos; > + size = SPDIF_QSUB_SIZE; > + reg = &spdif->srq; > + break; > + default: > + return; > + } > + > + dev_dbg(&pdev->dev, "isr: %c Channel receive register full\n", name); > + > + if (*pos >= size * 2) { > + *pos = 0; > + } else if (unlikely((*pos % size) + 3 > size)) { > + dev_err(&pdev->dev, "User bit receivce buffer overflow\n"); > + return; > + } > + > + val = spdif_read(reg); > + ctrl->subcode[*pos++] = val >> 16; > + ctrl->subcode[*pos++] = val >> 8; > + ctrl->subcode[*pos++] = val; > +} > + > +/* U/Q Channel sync found */ > +static void spdif_irq_uq_sync(struct fsl_spdif_priv *spdif_priv) > +{ > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + struct platform_device *pdev = spdif_priv->pdev; > + > + dev_dbg(&pdev->dev, "isr: U/Q Channel sync found\n"); > + > + /* U/Q buffer reset */ > + if (ctrl->qpos == 0) > + return; > + > + /* set ready to this buffer */ > + ctrl->ready_buf = (ctrl->qpos - 1) / SPDIF_QSUB_SIZE + 1; > +} > + > +/* U/Q Channel framing error */ > +static void spdif_irq_uq_err(struct fsl_spdif_priv *spdif_priv) > +{ > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 val; > + > + dev_dbg(&pdev->dev, "isr: U/Q Channel framing error\n"); > + > + /* read U/Q data and do buffer reset */ > + val = spdif_read(&spdif->sru); > + val = spdif_read(&spdif->srq); > + > + /* drop this U/Q buffer */ > + ctrl->ready_buf = 0; > + ctrl->upos = 0; > + ctrl->qpos = 0; > +} > + > +/* Get spdif interrupt status and clear the interrupt */ > +static u32 spdif_intr_status_clear(struct fsl_spdif_priv *spdif_priv) > +{ > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 val = spdif_read(&spdif->sisc); > + > + val &= spdif_read(&spdif->sie); > + spdif_write(&spdif->sisc, val); > + > + return val; > +} > + > +static irqreturn_t spdif_isr(int irq, void *devid) > +{ > + struct fsl_spdif_priv *spdif_priv = (struct fsl_spdif_priv *)devid; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 sis; > + > + sis = spdif_intr_status_clear(spdif_priv); > + > + if (sis & INT_DPLL_LOCKED) > + spdif_irq_dpll_lock(spdif_priv); > + > + if (sis & INT_TXFIFO_UNOV) > + dev_dbg(&pdev->dev, "isr: Tx FIFO under/overrun\n"); > + > + if (sis & INT_TXFIFO_RESYNC) > + dev_dbg(&pdev->dev, "isr: Tx FIFO resync\n"); > + > + if (sis & INT_CNEW) > + dev_dbg(&pdev->dev, "isr: cstatus new\n"); > + > + if (sis & INT_VAL_NOGOOD) > + dev_dbg(&pdev->dev, "isr: validity flag no good\n"); > + > + if (sis & INT_SYM_ERR) > + spdif_irq_sym_error(spdif_priv); > + > + if (sis & INT_BIT_ERR) > + dev_dbg(&pdev->dev, "isr: receiver found parity bit error\n"); > + > + if (sis & INT_URX_FUL) > + spdif_irq_uqrx_full(spdif_priv, 'U'); > + > + if (sis & INT_URX_OV) > + dev_dbg(&pdev->dev, "isr: U Channel receive register overrun\n"); > + > + if (sis & INT_QRX_FUL) > + spdif_irq_uqrx_full(spdif_priv, 'Q'); > + > + if (sis & INT_QRX_OV) > + dev_dbg(&pdev->dev, "isr: Q Channel receive register overrun\n"); > + > + if (sis & INT_UQ_SYNC) > + spdif_irq_uq_sync(spdif_priv); > + > + if (sis & INT_UQ_ERR) > + spdif_irq_uq_err(spdif_priv); > + > + if (sis & INT_RXFIFO_UNOV) > + dev_dbg(&pdev->dev, "isr: Rx FIFO under/overrun\n"); > + > + if (sis & INT_RXFIFO_RESYNC) > + dev_dbg(&pdev->dev, "isr: Rx FIFO resync\n"); > + > + if (sis & INT_LOSS_LOCK) > + spdif_irq_dpll_lock(spdif_priv); > + > + /* FIXME: Write Tx FIFO to clear TxEm */ > + if (sis & INT_TX_EM) > + dev_dbg(&pdev->dev, "isr: Tx FIFO empty\n"); > + > + /* FIXME: Read Rx FIFO to clear RxFIFOFul */ > + if (sis & INT_RXFIFO_FUL) > + dev_dbg(&pdev->dev, "isr: Rx FIFO full\n"); > + > + return IRQ_HANDLED; > +} > + > +static void spdif_softreset(struct fsl_spdif_priv *spdif_priv) > +{ > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + int cycle = 1000; > + > + spdif_write(&spdif->scr, SCR_SOFT_RESET); > + > + /* RESET bit would be cleared after finishing its reset procedure */ > + while ((spdif_read(&spdif->scr) & SCR_SOFT_RESET) && cycle--); > +} > + > +static void spdif_set_cstatus(struct spdif_mixer_control *ctrl, > + u8 mask, u8 cstatus) > +{ > + ctrl->ch_status[3] &= ~mask; > + ctrl->ch_status[3] |= cstatus & mask; > +} > + > +static u8 reverse_bits(u8 input) > +{ > + u8 i, output = 0; > + > + for (i = 8 ; i > 0 ; i--) { > + output <<= 1; > + output |= input & 0x01; > + input >>= 1; > + } > + > + return output; > +} Do we already have anything for this in the kernel? It could also be done using: u8 tmp = input; tmp = ((tmp & 0b10101010) >> 1) | ((tmp << 1) & 0b10101010); tmp = ((tmp & 0b11001100) >> 2) | ((tmp << 2) & 0b11001100); tmp = ((tmp & 0b11110000) >> 4) | ((tmp << 4) & 0b11110000); return tmp; > +static void spdif_write_channel_status(struct fsl_spdif_priv *spdif_priv) > +{ > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 ch_status; > + > + ch_status = (reverse_bits(ctrl->ch_status[0]) << 16) | > + (reverse_bits(ctrl->ch_status[1]) << 8) | > + reverse_bits(ctrl->ch_status[2]); > + spdif_write(&spdif->stcsch, ch_status); > + > + ch_status = reverse_bits(ctrl->ch_status[3]) << 16; > + spdif_write(&spdif->stcscl, ch_status); > + > + dev_dbg(&pdev->dev, "STCSCH: 0x%06x\n", spdif_read(&spdif->stcsch)); > + dev_dbg(&pdev->dev, "STCSCL: 0x%06x\n", spdif_read(&spdif->stcscl)); > +} > + > +/* > + * Check if the clock source setting cares about DPLL Locked condition > + * > + * The DPLL locked condition should depend on SoC design, being different > + * between different spdif_devtype. > + */ > +static inline bool spdif_rxclk_lock_check(enum spdif_rxclk_src clksrc) { > + > + switch (spdif_devtype) { > + case FSL_IMX6Q_SPDIF: > + if (clksrc <= SRPC_CLKSRC_4) > + return true; > + else if (clksrc <= SRPC_CLKSRC_9) > + return false; > + else if (clksrc <= SRPC_CLKSRC_11) > + return true; > + else > + return false; > + break; > + case FSL_IMX6SL_SPDIF: > + if (clksrc <= SRPC_CLKSRC_3) > + return true; > + else > + return false; > + break; > + default: > + return false; > + } > +} > + > +/* Set SPDIF PhaseConfig register for rx clock */ > +static int spdif_set_rx_clksrc(struct fsl_spdif_priv *spdif_priv, > + enum spdif_gainsel gainsel, int dpll_locked) > +{ > + enum spdif_rxclk_src clksrc = spdif_priv->rxclk_src; > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + > + if (clksrc >= SRPC_CLKSRC_MAX || gainsel >= GAINSEL_MULTI_MAX) > + return -EINVAL; > + > + if (!dpll_locked && spdif_rxclk_lock_check(clksrc)) > + clksrc += SRPC_CLKSRC_SEL_LOCKED; > + > + spdif_setmask(&spdif->srpc, SRPC_CLKSRC_SEL_MASK | SRPC_GAINSEL_MASK, > + SRPC_CLKSRC_SEL_SET(clksrc) | SRPC_GAINSEL_SET(gainsel)); > + > + return 0; > +} > + > +static int spdif_clk_set_rate(struct clk *clk, unsigned long rate) > +{ > + unsigned long rate_actual; > + > + rate_actual = clk_round_rate(clk, rate); > + clk_set_rate(clk, rate_actual); > + > + return 0; > +} > + > +static int spdif_set_sample_rate(struct snd_pcm_substream *substream, > + int sample_rate) > +{ > + struct snd_soc_pcm_runtime *rtd = substream->private_data; > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + unsigned long clk = -1, div = 1, csfs = 0; > + u32 stc, mask; > + > + switch (sample_rate) { > + case 32000: > + clk = spdif_priv->txclk_src; > + div = spdif_priv->txclk_div[SPDIF_TXRATE_32000]; > + csfs = IEC958_AES3_CON_FS_32000; > + break; > + case 44100: > + clk = spdif_priv->txclk_src; > + div = spdif_priv->txclk_div[SPDIF_TXRATE_44100]; > + csfs = IEC958_AES3_CON_FS_44100; > + break; > + case 48000: > + clk = spdif_priv->txclk_src; > + div = spdif_priv->txclk_div[SPDIF_TXRATE_48000]; > + csfs = IEC958_AES3_CON_FS_48000; > + break; > + default: > + dev_err(&pdev->dev, "unsupported samplerate %d\n", sample_rate); > + return -EINVAL; > + } > + > + if (clk < 0) { > + dev_err(&pdev->dev, "no defined %d clk src\n", sample_rate); > + return -EINVAL; > + } > + > + /* > + * The S/PDIF block needs a clock of 64 * fs * div. The S/PDIF block > + * will divide by (div). So request 64 * fs * (div+1) which will > + * get rounded. > + */ > + spdif_clk_set_rate(spdif_priv->txclk, 64 * sample_rate * (div + 1)); > + > + dev_dbg(&pdev->dev, "expected clock rate = %d\n", > + (int)(64 * sample_rate * div)); > + dev_dbg(&pdev->dev, "acutal clock rate = %d\n", > + (int)clk_get_rate(spdif_priv->txclk)); > + > + /* set fs field in consumer channel status */ > + spdif_set_cstatus(ctrl, IEC958_AES3_CON_FS, csfs); > + > + /* select clock source and divisor */ > + stc = STC_TXCLK_ALL_EN | STC_TXCLK_SRC_SET(clk) | STC_TXCLK_DIV(div); > + mask = STC_TXCLK_ALL_EN_MASK | STC_TXCLK_SRC_MASK | STC_TXCLK_DIV_MASK; > + spdif_setmask(&spdif->stc, mask, stc); > + > + dev_dbg(&pdev->dev, "set sample rate to %d\n", sample_rate); > + > + return 0; > +} > + > +int fsl_spdif_startup(struct snd_pcm_substream *substream, > + struct snd_soc_dai *cpu_dai) > +{ > + struct snd_soc_pcm_runtime *rtd = substream->private_data; > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 scr, mask; > + > + clk_enable(spdif_priv->coreclk); > + clk_enable(spdif_priv->txclk); > + > + /* Reset module and interrupts only for first initialization */ > + if (!cpu_dai->active) { > + spdif_softreset(spdif_priv); > + > + /* disable all the interrupts */ > + spdif_clrbits(&spdif->sie, 0xffffff); > + } > + > + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { > + scr = SCR_TXFIFO_AUTOSYNC | SCR_TXFIFO_CTRL_NORMAL | > + SCR_TXSEL_NORMAL | SCR_USRC_SEL_CHIP | > + SCR_TXFIFO_FSEL_IF8; > + mask = SCR_TXFIFO_AUTOSYNC_MASK | SCR_TXFIFO_CTRL_MASK | > + SCR_TXSEL_MASK | SCR_USRC_SEL_MASK | > + SCR_TXFIFO_FSEL_MASK; > + } else { > + scr = SCR_RXFIFO_FSEL_IF8 | SCR_RXFIFO_AUTOSYNC; > + mask = SCR_RXFIFO_FSEL_MASK | SCR_RXFIFO_AUTOSYNC_MASK| > + SCR_RXFIFO_CTL_MASK | SCR_RXFIFO_OFF_MASK; > + } > + spdif_setmask(&spdif->scr, mask, scr); > + > + /* Power up SPDIF module */ > + spdif_clrbits(&spdif->scr, SCR_LOW_POWER); > + > + return 0; > +} > + > +static void fsl_spdif_shutdown(struct snd_pcm_substream *substream, > + struct snd_soc_dai *cpu_dai) > +{ > + struct snd_soc_pcm_runtime *rtd = substream->private_data; > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 scr, mask; > + > + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { > + scr = 0; > + mask = SCR_TXFIFO_AUTOSYNC_MASK | SCR_TXFIFO_CTRL_MASK | > + SCR_TXSEL_MASK | SCR_USRC_SEL_MASK | > + SCR_TXFIFO_FSEL_MASK; > + } else { > + scr = SCR_RXFIFO_OFF | SCR_RXFIFO_CTL_ZERO; > + mask = SCR_RXFIFO_FSEL_MASK | SCR_RXFIFO_AUTOSYNC_MASK| > + SCR_RXFIFO_CTL_MASK | SCR_RXFIFO_OFF_MASK; > + } > + spdif_setmask(&spdif->scr, mask, scr); > + > + /* Power down SPDIF module only if tx&rx are both inactive */ > + if (!cpu_dai->active) { > + spdif_intr_status_clear(spdif_priv); > + spdif_setbits(&spdif->scr, SCR_LOW_POWER); > + } > + > + /* disable spdif clock */ > + clk_disable(spdif_priv->txclk); > + clk_disable(spdif_priv->coreclk); > +} > + > +static int fsl_spdif_hw_params(struct snd_pcm_substream *substream, > + struct snd_pcm_hw_params *params, > + struct snd_soc_dai *dai) > +{ > + struct snd_soc_pcm_runtime *rtd = substream->private_data; > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + struct platform_device *pdev = spdif_priv->pdev; > + u32 sample_rate = params_rate(params); > + int ret = 0; > + > + if (substream->stream == SNDRV_PCM_STREAM_PLAYBACK) { > + ret = spdif_set_sample_rate(substream, sample_rate); > + if (ret) { > + dev_err(&pdev->dev, "%s: set sample rate failed: %d\n", > + __func__, sample_rate); > + return ret; > + } > + spdif_set_cstatus(ctrl, IEC958_AES3_CON_CLOCK, > + IEC958_AES3_CON_CLOCK_1000PPM); > + spdif_write_channel_status(spdif_priv); > + } else { > + /* setup rx clock source */ > + ret = spdif_set_rx_clksrc(spdif_priv, SPDIF_DEFAULT_GAINSEL, 1); > + } > + > + return ret; > +} > + > +static int fsl_spdif_trigger(struct snd_pcm_substream *substream, > + int cmd, struct snd_soc_dai *dai) > +{ > + struct snd_soc_pcm_runtime *rtd = substream->private_data; > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(rtd->cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + int is_playack = (substream->stream == SNDRV_PCM_STREAM_PLAYBACK); > + u32 intr = is_playack ? INTR_FOR_PLAYBACK : INTR_FOR_CAPTURE; > + u32 dmaen = is_playack ? SCR_DMA_TX_EN : SCR_DMA_RX_EN;; > + > + switch (cmd) { > + case SNDRV_PCM_TRIGGER_START: > + case SNDRV_PCM_TRIGGER_RESUME: > + case SNDRV_PCM_TRIGGER_PAUSE_RELEASE: > + spdif_setbits(&spdif->sie, intr); > + spdif_setbits(&spdif->scr, dmaen); > + dumpregs(spdif_priv); > + break; > + case SNDRV_PCM_TRIGGER_STOP: > + case SNDRV_PCM_TRIGGER_SUSPEND: > + case SNDRV_PCM_TRIGGER_PAUSE_PUSH: > + spdif_clrbits(&spdif->scr, dmaen); > + spdif_clrbits(&spdif->sie, intr); > + break; > + default: > + return -EINVAL; > + } > + > + return 0; > +} > + > +struct snd_soc_dai_ops fsl_spdif_dai_ops = { > + .startup = fsl_spdif_startup, > + .hw_params = fsl_spdif_hw_params, > + .trigger = fsl_spdif_trigger, > + .shutdown = fsl_spdif_shutdown, > +}; > + > + > +/* > + * ============================================ > + * FSL SPDIF IEC958 controller(mixer) functions > + * > + * Channel status get/put control > + * User bit value get/put control > + * Valid bit value get control > + * DPLL lock status get control > + * User bit sync mode selection control > + * ============================================ > + */ > + > +static int fsl_spdif_info(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_info *uinfo) > +{ > + uinfo->type = SNDRV_CTL_ELEM_TYPE_IEC958; > + uinfo->count = 1; > + > + return 0; > +} > + > +static int fsl_spdif_pb_get(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *uvalue) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + > + uvalue->value.iec958.status[0] = ctrl->ch_status[0]; > + uvalue->value.iec958.status[1] = ctrl->ch_status[1]; > + uvalue->value.iec958.status[2] = ctrl->ch_status[2]; > + uvalue->value.iec958.status[3] = ctrl->ch_status[3]; > + > + return 0; > +} > + > +static int fsl_spdif_pb_put(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *uvalue) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + > + ctrl->ch_status[0] = uvalue->value.iec958.status[0]; > + ctrl->ch_status[1] = uvalue->value.iec958.status[1]; > + ctrl->ch_status[2] = uvalue->value.iec958.status[2]; > + ctrl->ch_status[3] = uvalue->value.iec958.status[3]; > + > + clk_enable(spdif_priv->coreclk); > + > + spdif_write_channel_status(spdif_priv); > + > + clk_disable(spdif_priv->coreclk); > + > + return 0; > +} > + > +/* Get channel status from SPDIF_RX_CCHAN register */ > +static int fsl_spdif_capture_get(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 cstatus; > + > + clk_enable(spdif_priv->coreclk); > + > + if (!(spdif_read(&spdif->sisc) & INT_CNEW)) { > + clk_disable(spdif_priv->coreclk); > + return -EAGAIN; > + } > + > + cstatus = spdif_read(&spdif->srcsch); > + ucontrol->value.iec958.status[0] = (cstatus >> 16) & 0xFF; > + ucontrol->value.iec958.status[1] = (cstatus >> 8) & 0xFF; > + ucontrol->value.iec958.status[2] = cstatus & 0xFF; > + > + cstatus = spdif_read(&spdif->srcscl); > + ucontrol->value.iec958.status[3] = (cstatus >> 16) & 0xFF; > + ucontrol->value.iec958.status[4] = (cstatus >> 8) & 0xFF; > + ucontrol->value.iec958.status[5] = cstatus & 0xFF; > + > + /* clear intr */ > + spdif_write(&spdif->sisc, INT_CNEW); > + > + clk_disable(spdif_priv->coreclk); > + > + return 0; > +} > + > +/* > + * Get User bits (subcode) from chip value which readed out > + * in UChannel register. > + */ > +static int fsl_spdif_subcode_get(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + unsigned long flags; > + int ret = 0; > + > + spin_lock_irqsave(&ctrl->ctl_lock, flags); > + if (ctrl->ready_buf) { > + int idx = (ctrl->ready_buf - 1) * SPDIF_UBITS_SIZE; > + memcpy(&ucontrol->value.iec958.subcode[0], > + &ctrl->subcode[idx], SPDIF_UBITS_SIZE); > + } else { > + ret = -EAGAIN; > + } > + spin_unlock_irqrestore(&ctrl->ctl_lock, flags); > + > + return ret; > +} > + > +/* Q-subcode infomation. The byte size is SPDIF_UBITS_SIZE/8 */ > +static int fsl_spdif_qinfo(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_info *uinfo) > +{ > + uinfo->type = SNDRV_CTL_ELEM_TYPE_BYTES; > + uinfo->count = SPDIF_QSUB_SIZE; > + > + return 0; > +} > + > +/* Get Q subcode from chip value which readed out in QChannel register */ > +static int fsl_spdif_qget(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct spdif_mixer_control *ctrl = &spdif_priv->fsl_spdif_control; > + unsigned long flags; > + int ret = 0; > + > + spin_lock_irqsave(&ctrl->ctl_lock, flags); > + if (ctrl->ready_buf) { > + int idx = (ctrl->ready_buf - 1) * SPDIF_QSUB_SIZE; > + memcpy(&ucontrol->value.bytes.data[0], > + &ctrl->qsub[idx], SPDIF_QSUB_SIZE); > + } else { > + ret = -EAGAIN; > + } > + spin_unlock_irqrestore(&ctrl->ctl_lock, flags); > + > + return ret; > +} > + > +/* Valid bit infomation */ > +static int fsl_spdif_vbit_info(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_info *uinfo) > +{ > + uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; > + uinfo->count = 1; > + uinfo->value.integer.min = 0; > + uinfo->value.integer.max = 1; > + > + return 0; > +} > + > +/* Get valid good bit from interrupt status register */ > +static int fsl_spdif_vbit_get(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 int_val; > + > + clk_enable(spdif_priv->coreclk); > + > + int_val = spdif_read(&spdif->sisc); > + ucontrol->value.integer.value[0] = (int_val & INT_VAL_NOGOOD) != 0; > + spdif_write(&spdif->sisc, INT_VAL_NOGOOD); > + > + clk_disable(spdif_priv->coreclk); > + > + return 0; > +} > + > +/* DPLL lock infomation */ > +static int fsl_spdif_rxrate_info(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_info *uinfo) > +{ > + uinfo->type = SNDRV_CTL_ELEM_TYPE_INTEGER; > + uinfo->count = 1; > + uinfo->value.integer.min = 16000; > + uinfo->value.integer.max = 96000; > + > + return 0; > +} > + > +static u32 gainsel_multi[GAINSEL_MULTI_MAX] = { > + 24, 16, 12, 8, 6, 4, 3, > +}; > + > +/* Get RX data clock rate given the SPDIF bus_clk */ > +static int spdif_get_rxclk_rate(struct fsl_spdif_priv *spdif_priv, > + enum spdif_gainsel gainsel) > +{ > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + struct platform_device *pdev = spdif_priv->pdev; > + u64 tmpval64, freqmeas, phaseconf, busclk_freq = 0; > + enum spdif_rxclk_src clksrc; > + > + clk_enable(spdif_priv->coreclk); > + > + freqmeas = spdif_read(&spdif->srfm); > + phaseconf = spdif_read(&spdif->srpc); > + > + clksrc = (phaseconf >> SRPC_CLKSRC_SEL_OFFSET) & 0xf; > + if (spdif_rxclk_lock_check(clksrc) && (phaseconf & SRPC_DPLL_LOCKED)) { > + /* get bus clock from system */ > + busclk_freq = clk_get_rate(spdif_priv->coreclk); > + } > + > + /* FreqMeas_CLK = (BUS_CLK * FreqMeas) / 2 ^ 10 / GAINSEL / 128 */ > + tmpval64 = (u64) busclk_freq * freqmeas; > + do_div(tmpval64, gainsel_multi[gainsel] * 1024); > + do_div(tmpval64, 128 * 1024); > + > + dev_dbg(&pdev->dev, "FreqMeas: %d\n", (int)freqmeas); > + dev_dbg(&pdev->dev, "BusclkFreq: %d\n", (int)busclk_freq); > + dev_dbg(&pdev->dev, "RxRate: %d\n", (int)tmpval64); > + > + clk_disable(spdif_priv->coreclk); > + > + return (int)tmpval64; > +} > + > +/* > + * Get DPLL lock or not info from stable interrupt status register. > + * User application must use this control to get locked, > + * then can do next PCM operation > + */ > +static int fsl_spdif_rxrate_get(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + int rate = spdif_get_rxclk_rate(spdif_priv, SPDIF_DEFAULT_GAINSEL); > + > + if (atomic_read(&spdif_priv->dpll_locked)) > + ucontrol->value.integer.value[0] = rate; > + else > + ucontrol->value.integer.value[0] = 0; > + > + return 0; > +} > + > +/* User bit sync mode info */ > +static int fsl_spdif_usync_info(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_info *uinfo) > +{ > + uinfo->type = SNDRV_CTL_ELEM_TYPE_BOOLEAN; > + uinfo->count = 1; > + uinfo->value.integer.min = 0; > + uinfo->value.integer.max = 1; > + > + return 0; > +} > + > +/* > + * User bit sync mode: > + * 1 CD User channel subcode > + * 0 Non-CD data > + */ > +static int fsl_spdif_usync_get(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 int_val; > + > + clk_enable(spdif_priv->coreclk); > + > + int_val = spdif_read(&spdif->srcd); > + ucontrol->value.integer.value[0] = (int_val & SRCD_CD_USER) != 0; > + > + clk_disable(spdif_priv->coreclk); > + > + return 0; > +} > + > +/* > + * User bit sync mode: > + * 1 CD User channel subcode > + * 0 Non-CD data > + */ > +static int fsl_spdif_usync_put(struct snd_kcontrol *kcontrol, > + struct snd_ctl_elem_value *ucontrol) > +{ > + struct snd_soc_dai *cpu_dai = snd_kcontrol_chip(kcontrol); > + struct fsl_spdif_priv *spdif_priv = snd_soc_dai_get_drvdata(cpu_dai); > + struct reg_spdif __iomem *spdif = spdif_priv->spdif; > + u32 int_val = ucontrol->value.integer.value[0] << SRCD_CD_USER_OFFSET; > + > + clk_enable(spdif_priv->coreclk); > + > + spdif_setmask(&spdif->srcd, SRCD_CD_USER, int_val); > + > + clk_disable(spdif_priv->coreclk); > + > + return 0; > +} > + > +/* FSL SPDIF IEC958 controller defines */ > +static struct snd_kcontrol_new fsl_spdif_ctrls[] = { > + /* status cchanel controller */ > + { > + .iface = SNDRV_CTL_ELEM_IFACE_MIXER, > + .name = SNDRV_CTL_NAME_IEC958("", PLAYBACK, DEFAULT), > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_WRITE | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_info, > + .get = fsl_spdif_pb_get, > + .put = fsl_spdif_pb_put, > + }, > + { > + .iface = SNDRV_CTL_ELEM_IFACE_PCM, > + .name = SNDRV_CTL_NAME_IEC958("", CAPTURE, DEFAULT), > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_info, > + .get = fsl_spdif_capture_get, > + }, > + /* user bits controller */ > + { > + .iface = SNDRV_CTL_ELEM_IFACE_PCM, > + .name = "IEC958 Subcode Capture Default", > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_info, > + .get = fsl_spdif_subcode_get, > + }, > + { > + .iface = SNDRV_CTL_ELEM_IFACE_PCM, > + .name = "IEC958 Q-subcode Capture Default", > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_qinfo, > + .get = fsl_spdif_qget, > + }, > + /* valid bit error controller */ > + { > + .iface = SNDRV_CTL_ELEM_IFACE_PCM, > + .name = "IEC958 V-Bit Errors", > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_vbit_info, > + .get = fsl_spdif_vbit_get, > + }, > + /* DPLL lock info get controller */ > + { > + .iface = SNDRV_CTL_ELEM_IFACE_PCM, > + .name = "RX Sample Rate", > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_rxrate_info, > + .get = fsl_spdif_rxrate_get, > + }, > + /* User bit sync mode set/get controller */ > + { > + .iface = SNDRV_CTL_ELEM_IFACE_PCM, > + .name = "IEC958 USyncMode CDText", > + .access = SNDRV_CTL_ELEM_ACCESS_READ | > + SNDRV_CTL_ELEM_ACCESS_WRITE | > + SNDRV_CTL_ELEM_ACCESS_VOLATILE, > + .info = fsl_spdif_usync_info, > + .get = fsl_spdif_usync_get, > + .put = fsl_spdif_usync_put, > + }, > +}; > + > +static int fsl_spdif_dai_probe(struct snd_soc_dai *dai) > +{ > + struct fsl_spdif_priv *spdif_private = snd_soc_dai_get_drvdata(dai); > + > + dai->playback_dma_data = &spdif_private->dma_params_tx; > + dai->capture_dma_data = &spdif_private->dma_params_rx; > + > + snd_soc_add_dai_controls(dai, fsl_spdif_ctrls, ARRAY_SIZE(fsl_spdif_ctrls)); > + > + return 0; > +} > + > +struct snd_soc_dai_driver fsl_spdif_dai = { > + .probe = &fsl_spdif_dai_probe, > + .playback = { > + .channels_min = 2, > + .channels_max = 2, > + .rates = FSL_SPDIF_RATES_PLAYBACK, > + .formats = FSL_SPDIF_FORMATS_PLAYBACK, > + }, > + .capture = { > + .channels_min = 2, > + .channels_max = 2, > + .rates = FSL_SPDIF_RATES_CAPTURE, > + .formats = FSL_SPDIF_FORMATS_CAPTURE, > + }, > + .ops = &fsl_spdif_dai_ops, > +}; > + > +static const struct snd_soc_component_driver fsl_spdif_component = { > + .name = "fsl-spdif", > +}; > + > +static void spdif_clk_cal_txdiv(struct fsl_spdif_priv *spdif_priv) > +{ > + struct platform_device *pdev = spdif_priv->pdev; > + struct clk *clk = spdif_priv->coreclk; > + u64 rate_ideal, rate_actual, sub, savesub; > + u32 i, div, arate, rate[] = {32000, 44100, 48000}; > + > + for (i = 0; i < SPDIF_TXRATE_MAX; i++, savesub = 100000) { > + for (div = 1; div <= 128; div++) { > + rate_ideal = rate[i] * (div + 1) * 64; > + rate_actual = clk_round_rate(clk, rate_ideal); > + > + arate = rate_actual / 64; > + arate /= div; > + if (arate == rate[i]) { > + savesub = 0; > + spdif_priv->txclk_div[i] = div; > + break; > + } else if (arate / rate[i] == 1) { > + sub = (arate - rate[i]) * 100000; > + do_div(sub, rate[i]); > + if (sub < savesub) { > + savesub = sub; > + spdif_priv->txclk_div[i] = div; > + } > + } else if (rate[i] / arate == 1) { > + sub = (rate[i] - arate) * 100000; > + do_div(sub, rate[i]); > + if (sub < savesub) { > + savesub = sub; > + spdif_priv->txclk_div[i] = div; > + } > + } > + } > + dev_dbg(&pdev->dev, "calculated %dHz div: %d\n", > + rate[i], spdif_priv->txclk_div[i]); > + } > +} > + > +static int fsl_spdif_probe(struct platform_device *pdev) > +{ > + const struct of_device_id *of_id = > + of_match_device(fsl_spdif_dt_ids, &pdev->dev); > + struct fsl_spdif_priv *spdif_priv; > + struct spdif_mixer_control *ctrl; > + struct device_node *np = pdev->dev.of_node; > + struct resource res; > + const char *p; > + int ret = 0; > + > + if (!of_device_is_available(np)) > + return -ENODEV; > + > + /* The DAI name is the last part of the full name of the node. */ > + p = strrchr(np->full_name, '/') + 1; > + spdif_priv = devm_kzalloc(&pdev->dev, > + sizeof(struct fsl_spdif_priv) + strlen(p), GFP_KERNEL); > + if (!spdif_priv) { > + dev_err(&pdev->dev, "could not allocate DAI object\n"); > + return -ENOMEM; > + } > + > + strcpy(spdif_priv->name, p); > + > + spdif_priv->pdev = pdev; > + > + if (of_id) > + pdev->id_entry = of_id->data; > + spdif_devtype = pdev->id_entry->driver_data; > + > + /* Initialize this copy of the CPU DAI driver structure */ > + memcpy(&spdif_priv->cpu_dai_drv, &fsl_spdif_dai, sizeof(fsl_spdif_dai)); > + spdif_priv->cpu_dai_drv.name = spdif_priv->name; > + > + /* Get the addresses and IRQ */ > + ret = of_address_to_resource(np, 0, &res); > + if (ret) { > + dev_err(&pdev->dev, "could not determine device resources\n"); > + return ret; > + } > + > + spdif_priv->spdif = of_iomap(np, 0); > + if (!spdif_priv->spdif) { > + dev_err(&pdev->dev, "could not map device resources\n"); > + return ret; > + } > + spdif_priv->spdif_phys = res.start; > + > + spdif_priv->irq = irq_of_parse_and_map(np, 0); > + if (spdif_priv->irq == NO_IRQ) { > + dev_err(&pdev->dev, "no irq for node %s\n", np->full_name); > + ret = -ENXIO; > + goto error_iomap; > + } > + > + /* The 'name' should not have any slashes in it. */ > + ret = devm_request_irq(&pdev->dev, spdif_priv->irq, spdif_isr, 0, > + spdif_priv->name, spdif_priv); > + if (ret) { > + dev_err(&pdev->dev, "could not claim irq %u\n", spdif_priv->irq); > + goto error_irqmap; > + } > + > + spdif_priv->coreclk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(spdif_priv->coreclk)) { > + ret = PTR_ERR(spdif_priv->coreclk); > + dev_err(&pdev->dev, "failed to get clock: %d\n", ret); > + goto error_irqmap; > + } > + > + clk_prepare(spdif_priv->coreclk); > + > + spdif_priv->txclk = devm_clk_get(&pdev->dev, "tx"); > + if (IS_ERR(spdif_priv->txclk)) { > + /* Use coreclk as default txclk */ > + spdif_priv->txclk = spdif_priv->coreclk; > + dev_warn(&pdev->dev, "using core clock as tx clk\n"); > + } else { > + clk_prepare(spdif_priv->txclk); > + } > + > + ret = of_property_read_u8(pdev->dev.of_node, > + "rx-clk-source", &spdif_priv->rxclk_src); > + if (ret) { > + dev_warn(&pdev->dev, "using default rx-clk-source\n"); > + spdif_priv->rxclk_src = DEFAULT_RXCLK_SRC; > + } > + > + ret = of_property_read_u8(pdev->dev.of_node, > + "tx-clk-source", &spdif_priv->txclk_src); > + if (ret) { > + dev_warn(&pdev->dev, "using default tx-clk-source\n"); > + spdif_priv->txclk_src = DEFAULT_TXCLK_SRC; > + } > + > + spdif_clk_cal_txdiv(spdif_priv); > + > + ctrl = &spdif_priv->fsl_spdif_control; > + /* initial spinlock for control data */ > + spin_lock_init(&ctrl->ctl_lock); > + > + /* init tx channel status default value */ > + ctrl->ch_status[0] = > + IEC958_AES0_CON_NOT_COPYRIGHT | IEC958_AES0_CON_EMPHASIS_5015; > + ctrl->ch_status[1] = IEC958_AES1_CON_DIGDIGCONV_ID; > + ctrl->ch_status[2] = 0x00; > + ctrl->ch_status[3] = > + IEC958_AES3_CON_FS_44100 | IEC958_AES3_CON_CLOCK_1000PPM; > + > + atomic_set(&spdif_priv->dpll_locked, 0); > + > + spdif_priv->dma_params_tx.maxburst = FSL_SPDIF_TXFIFO_WML; > + spdif_priv->dma_params_rx.maxburst = FSL_SPDIF_RXFIFO_WML; > + spdif_priv->dma_params_tx.addr = > + spdif_priv->spdif_phys + offsetof(struct reg_spdif, stl); > + spdif_priv->dma_params_rx.addr = > + spdif_priv->spdif_phys + offsetof(struct reg_spdif, srl); > + > + /* Register with ASoC */ > + dev_set_drvdata(&pdev->dev, spdif_priv); > + > + ret = snd_soc_register_component(&pdev->dev, &fsl_spdif_component, > + &spdif_priv->cpu_dai_drv, 1); > + if (ret) { > + dev_err(&pdev->dev, "failed to register DAI: %d\n", ret); > + goto error_dev; > + } > + > + ret = imx_pcm_dma_init(pdev); > + if (ret) { > + dev_err(&pdev->dev, "imx_pcm_dma_init failed: %d\n", ret); > + goto error_component; > + } > + > + return ret; > + > +error_component: > + snd_soc_unregister_component(&pdev->dev); > +error_dev: > + dev_set_drvdata(&pdev->dev, NULL); > + if (spdif_priv->txclk != spdif_priv->coreclk) { > + clk_unprepare(spdif_priv->txclk); > + clk_put(spdif_priv->txclk); > + } > + clk_unprepare(spdif_priv->coreclk); > + clk_put(spdif_priv->coreclk); Since you use devm_clk_get() above, devres will already do this. > +error_irqmap: > + irq_dispose_mapping(spdif_priv->irq); Hm, how does this interact with the devm_request_irq above? Disposing the mapping before the irq is freed sounds unsafe. > +error_iomap: > + iounmap(spdif_priv->spdif); There is a mixture of devres/devm and manual resource handling going on here. It's probably better to either go all the way or completely do it manually. > + > + return ret; > +} > + > +static int fsl_spdif_remove(struct platform_device *pdev) > +{ > + struct fsl_spdif_priv *spdif_priv = platform_get_drvdata(pdev); > + > + imx_pcm_dma_exit(pdev); > + snd_soc_unregister_component(&pdev->dev); > + > + if (spdif_priv->txclk != spdif_priv->coreclk) { > + clk_unprepare(spdif_priv->txclk); > + clk_put(spdif_priv->txclk); > + } > + clk_unprepare(spdif_priv->coreclk); > + clk_put(spdif_priv->coreclk); See above. > + > + irq_dispose_mapping(spdif_priv->irq); See above. > + iounmap(spdif_priv->spdif); > + > + dev_set_drvdata(&pdev->dev, NULL); > + > + return 0; > +} > + > +static struct platform_driver fsl_spdif_driver = { > + .driver = { > + .name = "fsl-spdif-dai", > + .owner = THIS_MODULE, > + .of_match_table = fsl_spdif_dt_ids, > + }, > + .probe = fsl_spdif_probe, > + .remove = fsl_spdif_remove, > +}; > + > +module_platform_driver(fsl_spdif_driver); > + > +MODULE_AUTHOR("Freescale Semiconductor, Inc."); > +MODULE_DESCRIPTION("Freescale S/PDIF CPU DAI Driver"); > +MODULE_LICENSE("GPL v2"); > +MODULE_ALIAS("platform:fsl_spdif"); > diff --git a/sound/soc/fsl/fsl_spdif.h b/sound/soc/fsl/fsl_spdif.h > new file mode 100644 > index 0000000..de8b383 > --- /dev/null > +++ b/sound/soc/fsl/fsl_spdif.h > @@ -0,0 +1,227 @@ > +/* > + * fsl_spdif.h - ALSA S/PDIF interface for the Freescale i.MX SoC > + * > + * Copyright (C) 2013 Freescale Semiconductor, Inc. > + * > + * Author: Nicolin Chen <b42378@xxxxxxxxxxxxx> > + * > + * Based on fsl_ssi.h > + * Author: Timur Tabi <timur@xxxxxxxxxxxxx> > + * Copyright 2007-2008 Freescale Semiconductor, Inc. > + * > + * This file is licensed under the terms of the GNU General Public License > + * version 2. This program is licensed "as is" without any warranty of any > + * kind, whether express or implied. > + */ > + > +#ifndef _FSL_SPDIF_DAI_H > +#define _FSL_SPDIF_DAI_H > + > +/* S/PDIF Register Map */ > +struct reg_spdif { > + __le32 scr; /* 0x.0000 - SPDIF Configuration Register */ > + __le32 srcd; /* 0x.0004 - CDText Control Register */ > + __le32 srpc; /* 0x.0008 - PhaseConfig Register */ > + __le32 sie; /* 0x.000C - InterruptEn Register */ > + __le32 sisc; /* 0x.0010 - InterruptStat(R)/Clear(W) Register */ > + __le32 srl; /* 0x.0014 - SPDIFRxLeft Register */ > + __le32 srr; /* 0x.0018 - SPDIFRxRight Register */ > + __le32 srcsch; /* 0x.001C - SPDIFRxCChannel_h Register */ > + __le32 srcscl; /* 0x.0020 - SPDIFRxCChannel_l Register */ > + __le32 sru; /* 0x.0024 - UchannelRx Register */ > + __le32 srq; /* 0x.0028 - QchannelRx Register */ > + __le32 stl; /* 0x.002C - SPDIFTxLeft Register */ > + __le32 str; /* 0x.0030 - SPDIFTxRight Register */ > + __le32 stcsch; /* 0x.0034 - SPDIFTxCChannelCons_h Register */ > + __le32 stcscl; /* 0x.0038 - SPDIFTxCChannelCons_l Register */ > + __le32 null1; /* 0x.003C - N/A */ > + __le32 null2; /* 0x.0040 - N/A */ > + __le32 srfm; /* 0x.0044 - FreqMeas Register */ > + __le32 null3; /* 0x.0048 - N/A */ > + __le32 null4; /* 0x.004C - N/A */ > + __le32 stc; /* 0x.0050 - SPDIFTxClk Register */ > +}; > + > +/* SPDIF Configuration register */ > +#define SCR_RXFIFO_CTL_OFFSET 23 > +#define SCR_RXFIFO_CTL_MASK (1 << SCR_RXFIFO_CTL_OFFSET) > +#define SCR_RXFIFO_CTL_ZERO (1 << SCR_RXFIFO_CTL_OFFSET) > +#define SCR_RXFIFO_OFF_OFFSET 22 > +#define SCR_RXFIFO_OFF_MASK (1 << SCR_RXFIFO_OFF_OFFSET) > +#define SCR_RXFIFO_OFF (1 << SCR_RXFIFO_OFF_OFFSET) > +#define SCR_RXFIFO_RST_OFFSET 21 > +#define SCR_RXFIFO_RST_MASK (1 << SCR_RXFIFO_RST_OFFSET) > +#define SCR_RXFIFO_RST (1 << SCR_RXFIFO_RST_OFFSET) > +#define SCR_RXFIFO_FSEL_OFFSET 19 > +#define SCR_RXFIFO_FSEL_MASK (0x3 << SCR_RXFIFO_FSEL_OFFSET) > +#define SCR_RXFIFO_FSEL_IF0 (0x0 << SCR_RXFIFO_FSEL_OFFSET) > +#define SCR_RXFIFO_FSEL_IF4 (0x1 << SCR_RXFIFO_FSEL_OFFSET) > +#define SCR_RXFIFO_FSEL_IF8 (0x2 << SCR_RXFIFO_FSEL_OFFSET) > +#define SCR_RXFIFO_FSEL_IF12 (0x3 << SCR_RXFIFO_FSEL_OFFSET) > +#define SCR_RXFIFO_AUTOSYNC_OFFSET 18 > +#define SCR_RXFIFO_AUTOSYNC_MASK (1 << SCR_RXFIFO_AUTOSYNC_OFFSET) > +#define SCR_RXFIFO_AUTOSYNC (1 << SCR_RXFIFO_AUTOSYNC_OFFSET) > +#define SCR_TXFIFO_AUTOSYNC_OFFSET 17 > +#define SCR_TXFIFO_AUTOSYNC_MASK (1 << SCR_TXFIFO_AUTOSYNC_OFFSET) > +#define SCR_TXFIFO_AUTOSYNC (1 << SCR_TXFIFO_AUTOSYNC_OFFSET) > +#define SCR_TXFIFO_FSEL_OFFSET 15 > +#define SCR_TXFIFO_FSEL_MASK (0x3 << SCR_TXFIFO_FSEL_OFFSET) > +#define SCR_TXFIFO_FSEL_IF0 (0x0 << SCR_TXFIFO_FSEL_OFFSET) > +#define SCR_TXFIFO_FSEL_IF4 (0x1 << SCR_TXFIFO_FSEL_OFFSET) > +#define SCR_TXFIFO_FSEL_IF8 (0x2 << SCR_TXFIFO_FSEL_OFFSET) > +#define SCR_TXFIFO_FSEL_IF12 (0x3 << SCR_TXFIFO_FSEL_OFFSET) > +#define SCR_LOW_POWER (1 << 13) > +#define SCR_SOFT_RESET (1 << 12) > +#define SCR_TXFIFO_CTRL_OFFSET 10 > +#define SCR_TXFIFO_CTRL_MASK (0x3 << SCR_TXFIFO_CTRL_OFFSET) > +#define SCR_TXFIFO_CTRL_ZERO (0x0 << SCR_TXFIFO_CTRL_OFFSET) > +#define SCR_TXFIFO_CTRL_NORMAL (0x1 << SCR_TXFIFO_CTRL_OFFSET) > +#define SCR_TXFIFO_CTRL_ONESAMPLE (0x2 << SCR_TXFIFO_CTRL_OFFSET) > +#define SCR_DMA_RX_EN_OFFSET 9 > +#define SCR_DMA_RX_EN_MASK (1 << SCR_DMA_RX_EN_OFFSET) > +#define SCR_DMA_RX_EN (1 << SCR_DMA_RX_EN_OFFSET) > +#define SCR_DMA_TX_EN_OFFSET 8 > +#define SCR_DMA_TX_EN_MASK (1 << SCR_DMA_TX_EN_OFFSET) > +#define SCR_DMA_TX_EN (1 << SCR_DMA_TX_EN_OFFSET) > +#define SCR_VAL_OFFSET 5 > +#define SCR_VAL_MASK (1 << SCR_VAL_OFFSET) > +#define SCR_VAL_CLEAR (1 << SCR_VAL_OFFSET) > +#define SCR_TXSEL_OFFSET 2 > +#define SCR_TXSEL_MASK (0x7 << SCR_TXSEL_OFFSET) > +#define SCR_TXSEL_OFF (0 << SCR_TXSEL_OFFSET) > +#define SCR_TXSEL_RX (1 << SCR_TXSEL_OFFSET) > +#define SCR_TXSEL_NORMAL (0x5 << SCR_TXSEL_OFFSET) > +#define SCR_USRC_SEL_OFFSET 0x0 > +#define SCR_USRC_SEL_MASK (0x3 << SCR_USRC_SEL_OFFSET) > +#define SCR_USRC_SEL_NONE (0x0 << SCR_USRC_SEL_OFFSET) > +#define SCR_USRC_SEL_RECV (0x1 << SCR_USRC_SEL_OFFSET) > +#define SCR_USRC_SEL_CHIP (0x3 << SCR_USRC_SEL_OFFSET) > + > +/* SPDIF CDText control */ > +#define SRCD_CD_USER_OFFSET 1 > +#define SRCD_CD_USER (1 << SRCD_CD_USER_OFFSET) > + > +/* SPDIF Phase Configuration register */ > +#define SRPC_DPLL_LOCKED (1 << 6) > +#define SRPC_CLKSRC_SEL_OFFSET 7 > +#define SRPC_CLKSRC_SEL_MASK (0xf << SRPC_CLKSRC_SEL_OFFSET) > +#define SRPC_CLKSRC_SEL_SET(x) ((x << SRPC_CLKSRC_SEL_OFFSET) & SRPC_CLKSRC_SEL_MASK) > +#define SRPC_CLKSRC_SEL_LOCKED 5 > +#define SRPC_GAINSEL_OFFSET 3 > +#define SRPC_GAINSEL_MASK (0x7 << SRPC_GAINSEL_OFFSET) > +#define SRPC_GAINSEL_SET(x) ((x << SRPC_GAINSEL_OFFSET) & SRPC_GAINSEL_MASK) > + > +/* SPDIF rx clock source */ > +enum spdif_rxclk_src { > + SRPC_CLKSRC_0 = 0, > + SRPC_CLKSRC_1, > + SRPC_CLKSRC_2, > + SRPC_CLKSRC_3, > + SRPC_CLKSRC_4, > + SRPC_CLKSRC_5, > + SRPC_CLKSRC_6, > + SRPC_CLKSRC_7, > + SRPC_CLKSRC_8, > + SRPC_CLKSRC_9, > + SRPC_CLKSRC_10, > + SRPC_CLKSRC_11, > + SRPC_CLKSRC_12, > + SRPC_CLKSRC_13, > + SRPC_CLKSRC_14, > + SRPC_CLKSRC_15, > +}; > +#define SRPC_CLKSRC_MAX (SRPC_CLKSRC_15 + 1) > +#define DEFAULT_RXCLK_SRC SRPC_CLKSRC_0 > + > +enum spdif_gainsel { > + GAINSEL_MULTI_24 = 0, > + GAINSEL_MULTI_16, > + GAINSEL_MULTI_12, > + GAINSEL_MULTI_8, > + GAINSEL_MULTI_6, > + GAINSEL_MULTI_4, > + GAINSEL_MULTI_3, > +}; > +#define GAINSEL_MULTI_MAX (GAINSEL_MULTI_3 + 1) > +#define SPDIF_DEFAULT_GAINSEL GAINSEL_MULTI_8 > + > +/* SPDIF interrupt mask define */ > +#define INT_DPLL_LOCKED (1 << 20) > +#define INT_TXFIFO_UNOV (1 << 19) > +#define INT_TXFIFO_RESYNC (1 << 18) > +#define INT_CNEW (1 << 17) > +#define INT_VAL_NOGOOD (1 << 16) > +#define INT_SYM_ERR (1 << 15) > +#define INT_BIT_ERR (1 << 14) > +#define INT_URX_FUL (1 << 10) > +#define INT_URX_OV (1 << 9) > +#define INT_QRX_FUL (1 << 8) > +#define INT_QRX_OV (1 << 7) > +#define INT_UQ_SYNC (1 << 6) > +#define INT_UQ_ERR (1 << 5) > +#define INT_RXFIFO_UNOV (1 << 4) > +#define INT_RXFIFO_RESYNC (1 << 3) > +#define INT_LOSS_LOCK (1 << 2) > +#define INT_TX_EM (1 << 1) > +#define INT_RXFIFO_FUL (1 << 0) > + > +/* SPDIF Clock register */ > +#define STC_SYSCLK_DIV_OFFSET 11 > +#define STC_SYSCLK_DIV_MASK (0x1ff << STC_TXCLK_SRC_OFFSET) > +#define STC_SYSCLK_DIV(x) ((((x) - 1) << STC_TXCLK_DIV_OFFSET) & STC_SYSCLK_DIV_MASK) > +#define STC_TXCLK_SRC_OFFSET 8 > +#define STC_TXCLK_SRC_MASK (0x7 << STC_TXCLK_SRC_OFFSET) > +#define STC_TXCLK_SRC_SET(x) ((x << STC_TXCLK_SRC_OFFSET) & STC_TXCLK_SRC_MASK) > +#define STC_TXCLK_ALL_EN_OFFSET 7 > +#define STC_TXCLK_ALL_EN_MASK (1 << STC_TXCLK_ALL_EN_OFFSET) > +#define STC_TXCLK_ALL_EN (1 << STC_TXCLK_ALL_EN_OFFSET) > +#define STC_TXCLK_DIV_OFFSET 0 > +#define STC_TXCLK_DIV_MASK (0x7ff << STC_TXCLK_DIV_OFFSET) > +#define STC_TXCLK_DIV(x) ((((x) - 1) << STC_TXCLK_DIV_OFFSET) & STC_TXCLK_DIV_MASK) > + > +/* SPDIF tx clksrc */ > +enum spdif_txclk_src { > + STC_TXCLK_SRC_0 = 0, > + STC_TXCLK_SRC_1, > + STC_TXCLK_SRC_2, > + STC_TXCLK_SRC_3, > + STC_TXCLK_SRC_4, > + STC_TXCLK_SRC_5, > + STC_TXCLK_SRC_6, > + STC_TXCLK_SRC_7, > +}; > +#define STC_TXCLK_SRC_MAX (STC_TXCLK_SRC_7 + 1) > +#define DEFAULT_TXCLK_SRC STC_TXCLK_SRC_1 > + > +/* SPDIF tx rate */ > +enum spdif_txrate { > + SPDIF_TXRATE_32000 = 0, > + SPDIF_TXRATE_44100, > + SPDIF_TXRATE_48000, > +}; > +#define SPDIF_TXRATE_MAX (SPDIF_TXRATE_48000 + 1) > + > + > +#define SPDIF_CSTATUS_BYTE 6 > +#define SPDIF_UBITS_SIZE 96 > +#define SPDIF_QSUB_SIZE (SPDIF_UBITS_SIZE / 8) > + > + > +#define FSL_SPDIF_RATES_PLAYBACK (SNDRV_PCM_RATE_32000 | \ > + SNDRV_PCM_RATE_44100 | \ > + SNDRV_PCM_RATE_48000) > + > +#define FSL_SPDIF_RATES_CAPTURE (SNDRV_PCM_RATE_16000 | \ > + SNDRV_PCM_RATE_32000 | \ > + SNDRV_PCM_RATE_44100 | \ > + SNDRV_PCM_RATE_48000 | \ > + SNDRV_PCM_RATE_64000 | \ > + SNDRV_PCM_RATE_96000) > + > +#define FSL_SPDIF_FORMATS_PLAYBACK (SNDRV_PCM_FMTBIT_S16_LE | \ > + SNDRV_PCM_FMTBIT_S20_3LE | \ > + SNDRV_PCM_FMTBIT_S24_LE) > + > +#define FSL_SPDIF_FORMATS_CAPTURE (SNDRV_PCM_FMTBIT_S24_LE) In principle, it should also be possible to let the SDMA engine only take the FIFOs' MSBs for S16_LE. Is this a limitation of the SDMA ROM script? > +#endif /* _FSL_SPDIF_DAI_H */ regards Philipp -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html