ASoC: omap-mcpdm: API to configure offset cancellation

The offset cancellation values can be different from board to board, even
on the same HW platform.
Provide a way for the machine drivers to configure the McPDM offset
cancellation.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

diff --git a/sound/soc/omap/omap-mcpdm.c b/sound/soc/omap/omap-mcpdm.c
index 2c9fa51..41d1706 100644 (file)
--- a/sound/soc/omap/omap-mcpdm.c
+++ b/sound/soc/omap/omap-mcpdm.c
@@ -59,6 +59,9 @@ struct omap_mcpdm {
        /* McPDM FIFO thresholds */
        u32 dn_threshold;
        u32 up_threshold;
+
+       /* McPDM dn offsets for rx1, and 2 channels */
+       u32 dn_rx_offset;
 };
 
 /*
@@ -183,6 +186,15 @@ static void omap_mcpdm_open_streams(struct omap_mcpdm *mcpdm)
                        MCPDM_DN_IRQ_EMPTY | MCPDM_DN_IRQ_FULL |
                        MCPDM_UP_IRQ_EMPTY | MCPDM_UP_IRQ_FULL);
 
+       /* Enable DN RX1/2 offset cancellation feature, if configured */
+       if (mcpdm->dn_rx_offset) {
+               u32 dn_offset = mcpdm->dn_rx_offset;
+
+               omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, dn_offset);
+               dn_offset |= (MCPDM_DN_OFST_RX1_EN | MCPDM_DN_OFST_RX2_EN);
+               omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, dn_offset);
+       }
+
        omap_mcpdm_write(mcpdm, MCPDM_REG_FIFO_CTRL_DN, mcpdm->dn_threshold);
        omap_mcpdm_write(mcpdm, MCPDM_REG_FIFO_CTRL_UP, mcpdm->up_threshold);
 
@@ -209,6 +221,10 @@ static void omap_mcpdm_close_streams(struct omap_mcpdm *mcpdm)
 
        /* Disable DMA request generation for uplink */
        omap_mcpdm_write(mcpdm, MCPDM_REG_DMAENABLE_CLR, MCPDM_DMA_UP_ENABLE);
+
+       /* Disable RX1/2 offset cancellation */
+       if (mcpdm->dn_rx_offset)
+               omap_mcpdm_write(mcpdm, MCPDM_REG_DN_OFFSET, 0);
 }
 
 static irqreturn_t omap_mcpdm_irq_handler(int irq, void *dev_id)
@@ -418,6 +434,15 @@ static struct snd_soc_dai_driver omap_mcpdm_dai = {
        .ops = &omap_mcpdm_dai_ops,
 };
 
+void omap_mcpdm_configure_dn_offsets(struct snd_soc_pcm_runtime *rtd,
+                                   u8 rx1, u8 rx2)
+{
+       struct omap_mcpdm *mcpdm = snd_soc_dai_get_drvdata(rtd->cpu_dai);
+
+       mcpdm->dn_rx_offset = MCPDM_DNOFST_RX1(rx1) | MCPDM_DNOFST_RX2(rx2);
+}
+EXPORT_SYMBOL_GPL(omap_mcpdm_configure_dn_offsets);
+
 static __devinit int asoc_mcpdm_probe(struct platform_device *pdev)
 {
        struct omap_mcpdm *mcpdm;

diff --git a/sound/soc/omap/omap-mcpdm.h b/sound/soc/omap/omap-mcpdm.h
index d23122a..de8cf26 100644 (file)
--- a/sound/soc/omap/omap-mcpdm.h
+++ b/sound/soc/omap/omap-mcpdm.h
@@ -92,4 +92,16 @@
 #define MCPDM_UP_THRES_MAX             0xF
 #define MCPDM_DN_THRES_MAX             0xF
 
+/*
+ * MCPDM_DN_OFFSET bit fields
+ */
+
+#define MCPDM_DN_OFST_RX1_EN           (1 << 0)
+#define MCPDM_DNOFST_RX1(x)            ((x & 0x1f) << 1)
+#define MCPDM_DN_OFST_RX2_EN           (1 << 8)
+#define MCPDM_DNOFST_RX2(x)            ((x & 0x1f) << 9)
+
+void omap_mcpdm_configure_dn_offsets(struct snd_soc_pcm_runtime *rtd,
+                                   u8 rx1, u8 rx2);
+
 #endif /* End of __OMAP_MCPDM_H__ */