From ed5e1cfbad32ccc5cd061b2fc7cb36dc1ae956e9 Mon Sep 17 00:00:00 2001 From: Nicolin Chen Date: Fri, 28 Mar 2014 19:39:25 +0800 Subject: ASoC: fsl_sai: Improve fsl_sai_isr() This patch improves fsl_sai_isr() in these ways: 1, Add comment for mask fetching code. 2, Return IRQ_NONE if the IRQ is not for the device. 3, Use regmap_write() instead of regmap_update_bits(). Signed-off-by: Nicolin Chen Signed-off-by: Mark Brown (cherry picked from commit 413312aa17ceefe7003ad690778ab72f023128f0) --- sound/soc/fsl/fsl_sai.c | 64 ++++++++++++++++++++++++++++++++++--------------- 1 file changed, 45 insertions(+), 19 deletions(-) (limited to 'sound/soc/fsl/fsl_sai.c') diff --git a/sound/soc/fsl/fsl_sai.c b/sound/soc/fsl/fsl_sai.c index 56da8c8c5960..7194d9280020 100644 --- a/sound/soc/fsl/fsl_sai.c +++ b/sound/soc/fsl/fsl_sai.c @@ -30,62 +30,88 @@ static irqreturn_t fsl_sai_isr(int irq, void *devid) { struct fsl_sai *sai = (struct fsl_sai *)devid; struct device *dev = &sai->pdev->dev; - u32 xcsr, mask; + u32 flags, xcsr, mask; + bool irq_none = true; - /* Only handle those what we enabled */ + /* + * Both IRQ status bits and IRQ mask bits are in the xCSR but + * different shifts. And we here create a mask only for those + * IRQs that we activated. + */ mask = (FSL_SAI_FLAGS >> FSL_SAI_CSR_xIE_SHIFT) << FSL_SAI_CSR_xF_SHIFT; /* Tx IRQ */ regmap_read(sai->regmap, FSL_SAI_TCSR, &xcsr); - xcsr &= mask; + flags = xcsr & mask; - if (xcsr & FSL_SAI_CSR_WSF) + if (flags) + irq_none = false; + else + goto irq_rx; + + if (flags & FSL_SAI_CSR_WSF) dev_dbg(dev, "isr: Start of Tx word detected\n"); - if (xcsr & FSL_SAI_CSR_SEF) + if (flags & FSL_SAI_CSR_SEF) dev_warn(dev, "isr: Tx Frame sync error detected\n"); - if (xcsr & FSL_SAI_CSR_FEF) { + if (flags & FSL_SAI_CSR_FEF) { dev_warn(dev, "isr: Transmit underrun detected\n"); /* FIFO reset for safety */ xcsr |= FSL_SAI_CSR_FR; } - if (xcsr & FSL_SAI_CSR_FWF) + if (flags & FSL_SAI_CSR_FWF) dev_dbg(dev, "isr: Enabled transmit FIFO is empty\n"); - if (xcsr & FSL_SAI_CSR_FRF) + if (flags & FSL_SAI_CSR_FRF) dev_dbg(dev, "isr: Transmit FIFO watermark has been reached\n"); - regmap_update_bits(sai->regmap, FSL_SAI_TCSR, - FSL_SAI_CSR_xF_W_MASK | FSL_SAI_CSR_FR, xcsr); + flags &= FSL_SAI_CSR_xF_W_MASK; + xcsr &= ~FSL_SAI_CSR_xF_MASK; + + if (flags) + regmap_write(sai->regmap, FSL_SAI_TCSR, flags | xcsr); +irq_rx: /* Rx IRQ */ regmap_read(sai->regmap, FSL_SAI_RCSR, &xcsr); - xcsr &= mask; + flags = xcsr & mask; - if (xcsr & FSL_SAI_CSR_WSF) + if (flags) + irq_none = false; + else + goto out; + + if (flags & FSL_SAI_CSR_WSF) dev_dbg(dev, "isr: Start of Rx word detected\n"); - if (xcsr & FSL_SAI_CSR_SEF) + if (flags & FSL_SAI_CSR_SEF) dev_warn(dev, "isr: Rx Frame sync error detected\n"); - if (xcsr & FSL_SAI_CSR_FEF) { + if (flags & FSL_SAI_CSR_FEF) { dev_warn(dev, "isr: Receive overflow detected\n"); /* FIFO reset for safety */ xcsr |= FSL_SAI_CSR_FR; } - if (xcsr & FSL_SAI_CSR_FWF) + if (flags & FSL_SAI_CSR_FWF) dev_dbg(dev, "isr: Enabled receive FIFO is full\n"); - if (xcsr & FSL_SAI_CSR_FRF) + if (flags & FSL_SAI_CSR_FRF) dev_dbg(dev, "isr: Receive FIFO watermark has been reached\n"); - regmap_update_bits(sai->regmap, FSL_SAI_RCSR, - FSL_SAI_CSR_xF_W_MASK | FSL_SAI_CSR_FR, xcsr); + flags &= FSL_SAI_CSR_xF_W_MASK; + xcsr &= ~FSL_SAI_CSR_xF_MASK; - return IRQ_HANDLED; + if (flags) + regmap_write(sai->regmap, FSL_SAI_TCSR, flags | xcsr); + +out: + if (irq_none) + return IRQ_NONE; + else + return IRQ_HANDLED; } static int fsl_sai_set_dai_sysclk_tr(struct snd_soc_dai *cpu_dai, -- cgit v1.2.3