Re: [PATCH v8 1/2] ASoC: fsl: Add S/PDIF CPU DAI driver

Thank you Sascha, I'll revise them all in v9

On Mon, Aug 19, 2013 at 02:34:49PM +0200, Sascha Hauer wrote:

Hi Nicolas,

Some misc other comments inline.

On Mon, Aug 19, 2013 at 08:08:48PM +0800, Nicolin Chen wrote:

quoted

This patch implements a device-tree-only CPU DAI driver for Freescale
+
+struct fsl_spdif_priv {
+	struct spdif_mixer_control fsl_spdif_control;
+	struct snd_soc_dai_driver cpu_dai_drv;
+	struct platform_device *pdev;
+	struct regmap *regmap;
+	atomic_t dpll_locked;

You don't need an atomic_t to track a bool variable. Use a plain bool or
int instead.

quoted

+	u8 txclk_div[SPDIF_TXRATE_MAX];
+	u8 txclk_src[SPDIF_TXRATE_MAX];
+	u8 rxclk_src;
+	struct clk *txclk[SPDIF_TXRATE_MAX];
+	struct clk *rxclk;
+	struct snd_dmaengine_dai_dma_data dma_params_tx;
+	struct snd_dmaengine_dai_dma_data dma_params_rx;
+
+	/* The name space will be allocated dynamically */
+	char name[0];
+};
+
+
+#ifdef DEBUG
+static void dumpregs(struct fsl_spdif_priv *spdif_priv)
+{
+	struct regmap *regmap = spdif_priv->regmap;
+	struct platform_device *pdev = spdif_priv->pdev;
+	u32 val, i;
+	int ret;
+
+	/* Valid address set of SPDIF is {[0x0-0x38], 0x44, 0x50} */
+	for (i = 0 ; i <= REG_SPDIF_STC; i += 4) {
+		ret = regmap_read(regmap, REG_SPDIF_SCR + i, &val);
+		if (!ret)
+			dev_dbg(&pdev->dev, "REG 0x%02x = 0x%06x\n", i, val);
+	}
+}
+#else
+static void dumpregs(struct fsl_spdif_priv *spdif_priv) {}
+#endif

Is this needed? regmap provides a register dump in debugfs.

quoted

+
+static int spdif_clk_set_rate(struct clk *clk, unsigned long rate)
+{
+	unsigned long rate_actual;
+
+	rate_actual = clk_round_rate(clk, rate);
+	return clk_set_rate(clk, rate_actual);
+}

clk_round_rate returns the rate which clk_set_rate would set if called
with the same rate. The clk_round_rate() is unnecessary.

quoted

+
+	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[rate]));

s/acutal/actual/

Also please use %ld instead of casting the unsigned long to int.

quoted

+
+	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);

Get rid of the casts

quoted

+
+	spdif_priv = devm_kzalloc(&pdev->dev,
+			sizeof(struct fsl_spdif_priv) + strlen(np->name) + 1, GFP_KERNEL);
+	if (!spdif_priv) {
+		dev_err(&pdev->dev, "could not allocate DAI object\n");

Please drop this message. You'll never see it.

quoted

+
+	for (i = 0; i < SPDIF_TXRATE_MAX; i++) {
+		ret = fsl_spdif_probe_txclk(spdif_priv, i);
+		if (ret)
+			return ret;
+	}
+
+	/* Prepare rx/tx clock */
+	clk_prepare(spdif_priv->rxclk);
+	for (i = 0; i < SPDIF_TXRATE_MAX; i++)
+		clk_prepare(spdif_priv->txclk[i]);

Why do you prepare all clocks instead of the one you actually use? Also,
no need to do this here. You can use clk_prepare_enable instead where
you have clk_enable now.

quoted

+
+/* 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,
+};

These are unused and look unnecessary.

quoted

+
+/* 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,
+};

Also unused.

Sascha

-- 
Pengutronix e.K.                           |                             |
Industrial Linux Solutions                 | http://www.pengutronix.de/  |
Peiner Str. 6-8, 31137 Hildesheim, Germany | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |