mailbox: imx: restructure code to make easy for new MU

Add imx_mu_generic_tx for data send and imx_mu_generic_rx for interrupt
data receive.

Pack original mu chans related code into imx_mu_init_generic

Add tx/rx/init hooks into imx_mu_dcfg

With these, it will be a bit easy to introduce i.MX8/8X SCU type
MU dedicated to communicate with SCU.

Reviewed-by: Oleksij Rempel <[e-mail]>
Signed-off-by: Peng Fan <[e-mail]>
Signed-off-by: Jassi Brar <[e-mail]>

drivers/mailbox/imx-mailbox.c

···
 	IMX_MU_TYPE_RXDB,	/* Rx doorbell */
 };
 
-struct imx_mu_dcfg {
-	u32	xTR[4];		/* Transmit Registers */
-	u32	xRR[4];		/* Receive Registers */
-	u32	xSR;		/* Status Register */
-	u32	xCR;		/* Control Register */
-};
-
 struct imx_mu_con_priv {
 	unsigned int		idx;
 	char			irq_desc[IMX_MU_CHAN_NAME_SIZE];
···
 	bool			side_b;
 };
 
-static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
-	.xTR	= {0x0, 0x4, 0x8, 0xc},
-	.xRR	= {0x10, 0x14, 0x18, 0x1c},
-	.xSR	= 0x20,
-	.xCR	= 0x24,
-};
-
-static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
-	.xTR	= {0x20, 0x24, 0x28, 0x2c},
-	.xRR	= {0x40, 0x44, 0x48, 0x4c},
-	.xSR	= 0x60,
-	.xCR	= 0x64,
+struct imx_mu_dcfg {
+	int (*tx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp, void *data);
+	int (*rx)(struct imx_mu_priv *priv, struct imx_mu_con_priv *cp);
+	void (*init)(struct imx_mu_priv *priv);
+	u32	xTR[4];		/* Transmit Registers */
+	u32	xRR[4];		/* Receive Registers */
+	u32	xSR;		/* Status Register */
+	u32	xCR;		/* Control Register */
 };
 
 static struct imx_mu_priv *to_imx_mu_priv(struct mbox_controller *mbox)
···
 	return val;
 }
 
+static int imx_mu_generic_tx(struct imx_mu_priv *priv,
+			     struct imx_mu_con_priv *cp,
+			     void *data)
+{
+	u32 *arg = data;
+
+	switch (cp->type) {
+	case IMX_MU_TYPE_TX:
+		imx_mu_write(priv, *arg, priv->dcfg->xTR[cp->idx]);
+		imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
+		break;
+	case IMX_MU_TYPE_TXDB:
+		imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIRn(cp->idx), 0);
+		tasklet_schedule(&cp->txdb_tasklet);
+		break;
+	default:
+		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int imx_mu_generic_rx(struct imx_mu_priv *priv,
+			     struct imx_mu_con_priv *cp)
+{
+	u32 dat;
+
+	dat = imx_mu_read(priv, priv->dcfg->xRR[cp->idx]);
+	mbox_chan_received_data(cp->chan, (void *)&dat);
+
+	return 0;
+}
+
 static void imx_mu_txdb_tasklet(unsigned long data)
 {
 	struct imx_mu_con_priv *cp = (struct imx_mu_con_priv *)data;
···
 	struct mbox_chan *chan = p;
 	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 	struct imx_mu_con_priv *cp = chan->con_priv;
-	u32 val, ctrl, dat;
+	u32 val, ctrl;
 
 	ctrl = imx_mu_read(priv, priv->dcfg->xCR);
 	val = imx_mu_read(priv, priv->dcfg->xSR);
···
 		imx_mu_xcr_rmw(priv, 0, IMX_MU_xCR_TIEn(cp->idx));
 		mbox_chan_txdone(chan, 0);
 	} else if (val == IMX_MU_xSR_RFn(cp->idx)) {
-		dat = imx_mu_read(priv, priv->dcfg->xRR[cp->idx]);
-		mbox_chan_received_data(chan, (void *)&dat);
+		priv->dcfg->rx(priv, cp);
 	} else if (val == IMX_MU_xSR_GIPn(cp->idx)) {
 		imx_mu_write(priv, IMX_MU_xSR_GIPn(cp->idx), priv->dcfg->xSR);
 		mbox_chan_received_data(chan, NULL);
···
 {
 	struct imx_mu_priv *priv = to_imx_mu_priv(chan->mbox);
 	struct imx_mu_con_priv *cp = chan->con_priv;
-	u32 *arg = data;
 
-	switch (cp->type) {
-	case IMX_MU_TYPE_TX:
-		imx_mu_write(priv, *arg, priv->dcfg->xTR[cp->idx]);
-		imx_mu_xcr_rmw(priv, IMX_MU_xCR_TIEn(cp->idx), 0);
-		break;
-	case IMX_MU_TYPE_TXDB:
-		imx_mu_xcr_rmw(priv, IMX_MU_xCR_GIRn(cp->idx), 0);
-		tasklet_schedule(&cp->txdb_tasklet);
-		break;
-	default:
-		dev_warn_ratelimited(priv->dev, "Send data on wrong channel type: %d\n", cp->type);
-		return -EINVAL;
-	}
-
-	return 0;
+	return priv->dcfg->tx(priv, cp, data);
 }
 
 static int imx_mu_startup(struct mbox_chan *chan)
···
 
 static void imx_mu_init_generic(struct imx_mu_priv *priv)
 {
+	unsigned int i;
+
+	for (i = 0; i < IMX_MU_CHANS; i++) {
+		struct imx_mu_con_priv *cp = &priv->con_priv[i];
+
+		cp->idx = i % 4;
+		cp->type = i >> 2;
+		cp->chan = &priv->mbox_chans[i];
+		priv->mbox_chans[i].con_priv = cp;
+		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
+			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
+	}
+
+	priv->mbox.num_chans = IMX_MU_CHANS;
+	priv->mbox.of_xlate = imx_mu_xlate;
+
 	if (priv->side_b)
 		return;
 
···
 	struct device_node *np = dev->of_node;
 	struct imx_mu_priv *priv;
 	const struct imx_mu_dcfg *dcfg;
-	unsigned int i;
 	int ret;
 
 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
···
 		return ret;
 	}
 
-	for (i = 0; i < IMX_MU_CHANS; i++) {
-		struct imx_mu_con_priv *cp = &priv->con_priv[i];
-
-		cp->idx = i % 4;
-		cp->type = i >> 2;
-		cp->chan = &priv->mbox_chans[i];
-		priv->mbox_chans[i].con_priv = cp;
-		snprintf(cp->irq_desc, sizeof(cp->irq_desc),
-			 "imx_mu_chan[%i-%i]", cp->type, cp->idx);
-	}
-
 	priv->side_b = of_property_read_bool(np, "fsl,mu-side-b");
+
+	priv->dcfg->init(priv);
 
 	spin_lock_init(&priv->xcr_lock);
 
 	priv->mbox.dev = dev;
 	priv->mbox.ops = &imx_mu_ops;
 	priv->mbox.chans = priv->mbox_chans;
-	priv->mbox.num_chans = IMX_MU_CHANS;
-	priv->mbox.of_xlate = imx_mu_xlate;
 	priv->mbox.txdone_irq = true;
 
 	platform_set_drvdata(pdev, priv);
-
-	imx_mu_init_generic(priv);
 
 	return devm_mbox_controller_register(dev, &priv->mbox);
 }
···
 
 	return 0;
 }
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx6sx = {
+	.tx	= imx_mu_generic_tx,
+	.rx	= imx_mu_generic_rx,
+	.init	= imx_mu_init_generic,
+	.xTR	= {0x0, 0x4, 0x8, 0xc},
+	.xRR	= {0x10, 0x14, 0x18, 0x1c},
+	.xSR	= 0x20,
+	.xCR	= 0x24,
+};
+
+static const struct imx_mu_dcfg imx_mu_cfg_imx7ulp = {
+	.tx	= imx_mu_generic_tx,
+	.rx	= imx_mu_generic_rx,
+	.init	= imx_mu_init_generic,
+	.xTR	= {0x20, 0x24, 0x28, 0x2c},
+	.xRR	= {0x40, 0x44, 0x48, 0x4c},
+	.xSR	= 0x60,
+	.xCR	= 0x64,
+};
 
 static const struct of_device_id imx_mu_dt_ids[] = {
 	{ .compatible = "fsl,imx7ulp-mu", .data = &imx_mu_cfg_imx7ulp },