MLK-16327-1: dma: fsl-edma-v3: make exclusive channel name for all edma channels

Since there are multi edmav3 instances on i.mx8, every edma channel name
is better unique.But so far, all edma channel name is 'edma-channel(id)-
tx',thus some edma channels which share the same channel id but different
edma instance will show the same channel name in kernel and this is not
friendly to debug in kernel.
  Now the edma channel name(interrupt-names property) is define in dts
as below:
        "edmaX-chanX-Xx"
             |     | |---> receive/transmit, r or t
             |     |---> channel id, the max number is 32
             |---> edma controller instance, 0, 1, 2,..etc
and get below correct name with 'cat /proc/interrupts':
 43:          0          0          0          0     GICv3 466 Level     edma0-chan8-rx
 44:          0          0          0          0     GICv3 467 Level     edma0-chan9-tx
 45:         79          0          0          0     GICv3 468 Level     edma0-chan10-rx
 46:        311          0          0          0     GICv3 469 Level     edma0-chan11-tx
 47:          0          0          0          0     GICv3 470 Level     edma0-chan12-rx
 48:          0          0          0          0     GICv3 471 Level     edma0-chan13-tx
 49:          0          0          0          0     GICv3 472 Level     edma0-chan14-rx
 50:          0          0          0          0     GICv3 473 Level     edma0-chan15-tx
 51:          0          0          0          0     GICv3 406 Level     edma2-chan0-tx
 52:          0          0          0          0     GICv3 407 Level     edma2-chan1-tx
 53:          0          0          0          0     GICv3 408 Level     edma2-chan2-tx
 54:          0          0          0          0     GICv3 409 Level     edma2-chan3-tx
 55:          0          0          0          0     GICv3 410 Level     edma2-chan4-tx
 56:          0          0          0          0     GICv3 411 Level     edma2-chan5-tx
 57:          0          0          0          0     GICv3 442 Level     edma2-chan6-rx, edma2-chan7-tx

Signed-off-by: Robin Gong <yibin.gong@nxp.com>
Reviewed-by: Shengjiu Wang <shengjiu.wang@nxp.com>
(cherry picked from commit af8e197a92c9c024ec4fbfcf543d744e81748773)

Documentation/devicetree/bindings/dma/fsl-edma-v3.txt

@@ -12,8 +12,12 @@ Required properties:
 - reg : Specifies base physical address(s) and size of the eDMA channel registers.
 	Each eDMA channel has separated register's address and size.
 - interrupts : A list of interrupt-specifiers, each channel has one interrupt.
-- interrupt-names : Should contain:
-	"edma-chan12-tx" - the channel12 transmission interrupt
+- interrupt-names : Should contain below template:
+	"edmaX-chanX-Xx"
+	     |     | |---> receive/transmit, r or t
+	     |     |---> channel id, the max number is 32
+	     |---> edma controller instance, 0, 1, 2,..etc
+
 - #dma-cells : Must be <3>.
 	The 1st cell specifies the channel ID.
 	The 2nd cell specifies the channel priority.
@@ -40,8 +44,8 @@ edma0: dma-controller@40018000 {
 		     <GIC_SPI 435 IRQ_TYPE_LEVEL_HIGH>,
 		     <GIC_SPI 436 IRQ_TYPE_LEVEL_HIGH>,
 		     <GIC_SPI 437 IRQ_TYPE_LEVEL_HIGH>;
-	interrupt-names = "edma-chan12-tx", "edma-chan13-tx",
-			  "edma-chan14-tx", "edma-chan15-tx";
+	interrupt-names = "edma0-chan12-rx", "edma0-chan13-tx",
+			  "edma0-chan14-rx", "edma0-chan15-tx";
 	status = "okay";
 };
 

drivers/dma/fsl-edma-v3.c

@@ -107,6 +107,10 @@
 #define ARGS_REMOTE			BIT(1)
 #define ARGS_DFIFO			BIT(2)
 
+/* channel name template define in dts */
+#define CHAN_PREFIX			"edma0-chan"
+#define CHAN_POSFIX			"-tx"
+
 struct fsl_edma3_hw_tcd {
 	__le32	saddr;
 	__le16	soff;
@@ -806,7 +810,10 @@ static int fsl_edma3_probe(struct platform_device *pdev)
 	INIT_LIST_HEAD(&fsl_edma3->dma_dev.channels);
 	for (i = 0; i < fsl_edma3->n_chans; i++) {
 		struct fsl_edma3_chan *fsl_chan = &fsl_edma3->chans[i];
-		char *txirq_name = fsl_chan->txirq_name;
+		const char *txirq_name = fsl_chan->txirq_name;
+		char chanid[3], id_len = 0;
+		char *p = chanid;
+		unsigned long val;
 
 		fsl_chan->edma3 = fsl_edma3;
 		/* Get per channel membase */
@@ -819,7 +826,31 @@ static int fsl_edma3_probe(struct platform_device *pdev)
 		 * channel0:0x10000, channel1:0x20000... total 32 channels
 		 */
 		fsl_chan->hw_chanid = (res->start >> 16) & 0x1f;
-		sprintf(txirq_name, "edma-chan%d-tx", fsl_chan->hw_chanid);
+
+		ret = of_property_read_string_index(np, "interrupt-names", i,
+							&txirq_name);
+		if (ret) {
+			dev_err(&pdev->dev, "read interrupt-names fail.\n");
+			return ret;
+		}
+		/* Get channel id length from dts, one-digit or double-digit */
+		id_len = strlen(txirq_name) - strlen(CHAN_PREFIX) -
+			 strlen(CHAN_POSFIX);
+		if (id_len > 2) {
+			dev_err(&pdev->dev, "%s is edmaX-chanX-tx in dts?\n",
+				res->name);
+			return -EINVAL;
+		}
+		/* Grab channel id from txirq_name */
+		strncpy(p, txirq_name + strlen(CHAN_PREFIX), id_len);
+		*(p + id_len) = '\0';
+
+		/* check if the channel id match well with hw_chanid */
+		ret = kstrtoul(chanid, 0, &val);
+		if (ret || val != fsl_chan->hw_chanid) {
+			dev_err(&pdev->dev, "%s,wrong id?\n", txirq_name);
+			return -EINVAL;
+		}
 
 		/* request channel irq */
 		fsl_chan->txirq = platform_get_irq_byname(pdev, txirq_name);