3  * atmel_ssc_dai.c  --  ALSA SoC ATMEL SSC Audio Layer Platform driver
11  * Based on at91-ssc.c by
25 #include <linux/atmel-ssc.h>
39  * SSC PDC registers required by the PCM DMA engine.
56  * SSC & PDC status bits for transmit and receive.
136  * SSC interrupt handler.  Passes PDC interrupts to the DMA
147 	ssc_sr = (unsigned long)ssc_readl(ssc_p->ssc->regs, SR)  in atmel_ssc_interrupt()
148 			& (unsigned long)ssc_readl(ssc_p->ssc->regs, IMR);  in atmel_ssc_interrupt()
151 	 * Loop through the substreams attached to this SSC.  If  in atmel_ssc_interrupt()
176  * Serial Clock Ratio Considerations section from the SSC documentation:
180  *   This allows the SSC to support many slave-mode data transfers.
189  * SSC divider restrictions.
195 	struct ssc_device *ssc = ssc_p->ssc;  in atmel_ssc_hw_rule_rate()  local
215 		    && ssc->clk_from_rk_pin)  in atmel_ssc_hw_rule_rate()
225 		    && !ssc->clk_from_rk_pin)  in atmel_ssc_hw_rule_rate()
279 		ssc_readl(ssc_p->ssc->regs, SR));  in atmel_ssc_startup()
281 	/* Enable PMC peripheral clock for this SSC */  in atmel_ssc_startup()
283 	ret = clk_enable(ssc_p->ssc->clk);  in atmel_ssc_startup()
287 	ssc_p->mck_rate = clk_get_rate(ssc_p->ssc->clk);  in atmel_ssc_startup()
289 	/* Reset the SSC unless initialized to keep it in a clean state */  in atmel_ssc_startup()
291 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));  in atmel_ssc_startup()
313 	dma_params->ssc = ssc_p->ssc;  in atmel_ssc_startup()
329  * Shutdown.  Clear DMA parameters and shutdown the SSC if there
348 		dma_params->ssc = NULL;  in atmel_ssc_shutdown()
358 			free_irq(ssc_p->ssc->irq, ssc_p);  in atmel_ssc_shutdown()
362 		/* Reset the SSC */  in atmel_ssc_shutdown()
363 		ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_SWRST));  in atmel_ssc_shutdown()
364 		/* Clear the SSC dividers */  in atmel_ssc_shutdown()
369 	/* Shutdown the SSC clock. */  in atmel_ssc_shutdown()
371 	clk_disable(ssc_p->ssc->clk);  in atmel_ssc_shutdown()
389  * Record SSC clock dividers for use in hw_params().
455  * Configure the SSC.
464 	struct ssc_device *ssc = ssc_p->ssc;  in atmel_ssc_hw_params()  local
554 	 * Compute SSC register settings.  in atmel_ssc_hw_params()
614 		 * SSC provides BCLK  in atmel_ssc_hw_params()
616 		 * The SSC transmit and receive clocks are generated from the  in atmel_ssc_hw_params()
618 		 * on the SSC TK line.  in atmel_ssc_hw_params()
626 		rcmr |=	  SSC_BF(RCMR_CKS, ssc->clk_from_rk_pin ?  in atmel_ssc_hw_params()
630 		tcmr |=	  SSC_BF(TCMR_CKS, ssc->clk_from_rk_pin ?  in atmel_ssc_hw_params()
660 	if (fslen_ext && !ssc->pdata->has_fslen_ext) {  in atmel_ssc_hw_params()
661 		dev_err(dai->dev, "sample size %d is too large for SSC device\n",  in atmel_ssc_hw_params()
671 		if (!ssc_p->ssc->pdata->use_dma) {  in atmel_ssc_hw_params()
672 			ssc_writel(ssc_p->ssc->regs, PDC_RPR, 0);  in atmel_ssc_hw_params()
673 			ssc_writel(ssc_p->ssc->regs, PDC_RCR, 0);  in atmel_ssc_hw_params()
674 			ssc_writel(ssc_p->ssc->regs, PDC_RNPR, 0);  in atmel_ssc_hw_params()
675 			ssc_writel(ssc_p->ssc->regs, PDC_RNCR, 0);  in atmel_ssc_hw_params()
677 			ssc_writel(ssc_p->ssc->regs, PDC_TPR, 0);  in atmel_ssc_hw_params()
678 			ssc_writel(ssc_p->ssc->regs, PDC_TCR, 0);  in atmel_ssc_hw_params()
679 			ssc_writel(ssc_p->ssc->regs, PDC_TNPR, 0);  in atmel_ssc_hw_params()
680 			ssc_writel(ssc_p->ssc->regs, PDC_TNCR, 0);  in atmel_ssc_hw_params()
683 		ret = request_irq(ssc_p->ssc->irq, atmel_ssc_interrupt, 0,  in atmel_ssc_hw_params()
689 			clk_disable(ssc_p->ssc->clk);  in atmel_ssc_hw_params()
696 	/* set SSC clock mode register */  in atmel_ssc_hw_params()
697 	ssc_writel(ssc_p->ssc->regs, CMR, cmr_div);  in atmel_ssc_hw_params()
700 	ssc_writel(ssc_p->ssc->regs, RCMR, rcmr);  in atmel_ssc_hw_params()
701 	ssc_writel(ssc_p->ssc->regs, RFMR, rfmr);  in atmel_ssc_hw_params()
704 	ssc_writel(ssc_p->ssc->regs, TCMR, tcmr);  in atmel_ssc_hw_params()
705 	ssc_writel(ssc_p->ssc->regs, TFMR, tfmr);  in atmel_ssc_hw_params()
707 	pr_debug("atmel_ssc_dai,hw_params: SSC initialized\n");  in atmel_ssc_hw_params()
727 	ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);  in atmel_ssc_prepare()
728 	ssc_writel(ssc_p->ssc->regs, IDR, dma_params->mask->ssc_error);  in atmel_ssc_prepare()
732 			ssc_readl(ssc_p->ssc->regs, SR));  in atmel_ssc_prepare()
755 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_enable);  in atmel_ssc_trigger()
758 		ssc_writel(ssc_p->ssc->regs, CR, dma_params->mask->ssc_disable);  in atmel_ssc_trigger()
776 	ssc_p->ssc_state.ssc_sr = ssc_readl(ssc_p->ssc->regs, SR);  in atmel_ssc_suspend()
777 	ssc_writel(ssc_p->ssc->regs, CR, SSC_BIT(CR_TXDIS) | SSC_BIT(CR_RXDIS));  in atmel_ssc_suspend()
780 	ssc_p->ssc_state.ssc_imr = ssc_readl(ssc_p->ssc->regs, IMR);  in atmel_ssc_suspend()
781 	ssc_writel(ssc_p->ssc->regs, IDR, ssc_p->ssc_state.ssc_imr);  in atmel_ssc_suspend()
783 	ssc_p->ssc_state.ssc_cmr = ssc_readl(ssc_p->ssc->regs, CMR);  in atmel_ssc_suspend()
784 	ssc_p->ssc_state.ssc_rcmr = ssc_readl(ssc_p->ssc->regs, RCMR);  in atmel_ssc_suspend()
785 	ssc_p->ssc_state.ssc_rfmr = ssc_readl(ssc_p->ssc->regs, RFMR);  in atmel_ssc_suspend()
786 	ssc_p->ssc_state.ssc_tcmr = ssc_readl(ssc_p->ssc->regs, TCMR);  in atmel_ssc_suspend()
787 	ssc_p->ssc_state.ssc_tfmr = ssc_readl(ssc_p->ssc->regs, TFMR);  in atmel_ssc_suspend()
803 	/* restore SSC register settings */  in atmel_ssc_resume()
804 	ssc_writel(ssc_p->ssc->regs, TFMR, ssc_p->ssc_state.ssc_tfmr);  in atmel_ssc_resume()
805 	ssc_writel(ssc_p->ssc->regs, TCMR, ssc_p->ssc_state.ssc_tcmr);  in atmel_ssc_resume()
806 	ssc_writel(ssc_p->ssc->regs, RFMR, ssc_p->ssc_state.ssc_rfmr);  in atmel_ssc_resume()
807 	ssc_writel(ssc_p->ssc->regs, RCMR, ssc_p->ssc_state.ssc_rcmr);  in atmel_ssc_resume()
808 	ssc_writel(ssc_p->ssc->regs, CMR, ssc_p->ssc_state.ssc_cmr);  in atmel_ssc_resume()
811 	ssc_writel(ssc_p->ssc->regs, IER, ssc_p->ssc_state.ssc_imr);  in atmel_ssc_resume()
819 	ssc_writel(ssc_p->ssc->regs, CR, cr);  in atmel_ssc_resume()
856 	.name			= "atmel-ssc",
864 	struct ssc_device *ssc = dev_get_drvdata(dev);  in asoc_ssc_init()  local
874 	if (ssc->pdata->use_dma)  in asoc_ssc_init()
888  * atmel_ssc_set_audio - Allocate the specified SSC for audio use.
893 	struct ssc_device *ssc;  in atmel_ssc_set_audio()  local
895 	/* If we can grab the SSC briefly to parent the DAI device off it */  in atmel_ssc_set_audio()
896 	ssc = ssc_request(ssc_id);  in atmel_ssc_set_audio()
897 	if (IS_ERR(ssc)) {  in atmel_ssc_set_audio()
898 		pr_err("Unable to parent ASoC SSC DAI on SSC: %ld\n",  in atmel_ssc_set_audio()
899 			PTR_ERR(ssc));  in atmel_ssc_set_audio()
900 		return PTR_ERR(ssc);  in atmel_ssc_set_audio()
902 		ssc_info[ssc_id].ssc = ssc;  in atmel_ssc_set_audio()
905 	return asoc_ssc_init(&ssc->pdev->dev);  in atmel_ssc_set_audio()
911 	struct ssc_device *ssc = ssc_info[ssc_id].ssc;  in atmel_ssc_put_audio()  local
913 	ssc_free(ssc);  in atmel_ssc_put_audio()
919 MODULE_DESCRIPTION("ATMEL SSC ASoC Interface");