forked from ~ljy/RK356X_SDK_RELEASE
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2024-02-19 1c055e55a242a33e574e48be530e06770a210dcd 
 kernel/drivers/tty/serial/xilinx_uartps.c
....@@ -9,10 +9,6 @@
99  * in the code.
1010  */
1111 
12
-#if defined(CONFIG_SERIAL_XILINX_PS_UART_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
13
-#define SUPPORT_SYSRQ
14
-#endif
15
-
1612 #include <linux/platform_device.h>
1713 #include <linux/serial.h>
1814 #include <linux/console.h>
....@@ -32,19 +28,19 @@
3228 #define CDNS_UART_NAME		"xuartps"
3329 #define CDNS_UART_MAJOR		0	/* use dynamic node allocation */
3430 #define CDNS_UART_MINOR		0	/* works best with devtmpfs */
35
-#define CDNS_UART_NR_PORTS	2
31
+#define CDNS_UART_NR_PORTS	16
3632 #define CDNS_UART_FIFO_SIZE	64	/* FIFO size */
3733 #define CDNS_UART_REGISTER_SPACE	0x1000
3834 #define TX_TIMEOUT		500000
3935 
4036 /* Rx Trigger level */
4137 static int rx_trigger_level = 56;
42
-module_param(rx_trigger_level, uint, S_IRUGO);
38
+module_param(rx_trigger_level, uint, 0444);
4339 MODULE_PARM_DESC(rx_trigger_level, "Rx trigger level, 1-63 bytes");
4440 
4541 /* Rx Timeout */
4642 static int rx_timeout = 10;
47
-module_param(rx_timeout, uint, S_IRUGO);
43
+module_param(rx_timeout, uint, 0444);
4844 MODULE_PARM_DESC(rx_timeout, "Rx timeout, 1-255");
4945 
5046 /* Register offsets for the UART. */
....@@ -160,6 +156,16 @@
160156 #define CDNS_UART_MODEMCR_DTR	0x00000001 /* Data Terminal Ready */
161157 
162158 /*
159
+ * Modem Status register:
160
+ * The read/write Modem Status register reports the interface with the modem
161
+ * or data set, or a peripheral device emulating a modem.
162
+ */
163
+#define CDNS_UART_MODEMSR_DCD	BIT(7) /* Data Carrier Detect */
164
+#define CDNS_UART_MODEMSR_RI	BIT(6) /* Ting Indicator */
165
+#define CDNS_UART_MODEMSR_DSR	BIT(5) /* Data Set Ready */
166
+#define CDNS_UART_MODEMSR_CTS	BIT(4) /* Clear To Send */
167
+
168
+/*
163169  * Channel Status Register:
164170  * The channel status register (CSR) is provided to enable the control logic
165171  * to monitor the status of bits in the channel interrupt status register,
....@@ -182,6 +188,7 @@
182188  * @port:		Pointer to the UART port
183189  * @uartclk:		Reference clock
184190  * @pclk:		APB clock
191
+ * @cdns_uart_driver:	Pointer to UART driver
185192  * @baud:		Current baud rate
186193  * @clk_rate_change_nb:	Notifier block for clock changes
187194  * @quirks:		Flags for RXBS support.
....@@ -190,15 +197,17 @@
190197 	struct uart_port	*port;
191198 	struct clk		*uartclk;
192199 	struct clk		*pclk;
200
+	struct uart_driver	*cdns_uart_driver;
193201 	unsigned int		baud;
194202 	struct notifier_block	clk_rate_change_nb;
195203 	u32			quirks;
204
+	bool cts_override;
196205 };
197206 struct cdns_platform_data {
198207 	u32 quirks;
199208 };
200209 #define to_cdns_uart(_nb) container_of(_nb, struct cdns_uart, \
201
-		clk_rate_change_nb);
210
+		clk_rate_change_nb)
202211 
203212 /**
204213  * cdns_uart_handle_rx - Handle the received bytes along with Rx errors.
....@@ -311,15 +320,16 @@
311320 	} else {
312321 		numbytes = port->fifosize;
313322 		while (numbytes && !uart_circ_empty(&port->state->xmit) &&
314
-		       !(readl(port->membase + CDNS_UART_SR) & CDNS_UART_SR_TXFULL)) {
323
+		       !(readl(port->membase + CDNS_UART_SR) &
324
+						CDNS_UART_SR_TXFULL)) {
315325 			/*
316326 			 * Get the data from the UART circular buffer
317327 			 * and write it to the cdns_uart's TX_FIFO
318328 			 * register.
319329 			 */
320330 			writel(
321
-				port->state->xmit.buf[port->state->xmit.
322
-				tail], port->membase + CDNS_UART_FIFO);
331
+				port->state->xmit.buf[port->state->xmit.tail],
332
+					port->membase + CDNS_UART_FIFO);
323333 
324334 			port->icount.tx++;
325335 
....@@ -365,6 +375,8 @@
365375 		isrstatus &= ~CDNS_UART_IXR_TXEMPTY;
366376 	}
367377 
378
+	isrstatus &= port->read_status_mask;
379
+	isrstatus &= ~port->ignore_status_mask;
368380 	/*
369381 	 * Skip RX processing if RX is disabled as RXEMPTY will never be set
370382 	 * as read bytes will not be removed from the FIFO.
....@@ -534,7 +546,7 @@
534546 
535547 		cdns_uart->baud = cdns_uart_set_baud_rate(cdns_uart->port,
536548 				cdns_uart->baud);
537
-		/* fall through */
549
+		fallthrough;
538550 	case ABORT_RATE_CHANGE:
539551 		if (!locked)
540552 			spin_lock_irqsave(&cdns_uart->port->lock, flags);
....@@ -641,8 +653,8 @@
641653 	unsigned int status;
642654 
643655 	status = readl(port->membase + CDNS_UART_SR) &
644
-				CDNS_UART_SR_TXEMPTY;
645
-	return status ? TIOCSER_TEMT : 0;
656
+		       (CDNS_UART_SR_TXEMPTY | CDNS_UART_SR_TACTIVE);
657
+	return (status == CDNS_UART_SR_TXEMPTY) ? TIOCSER_TEMT : 0;
646658 }
647659 
648660 /**
....@@ -681,23 +693,11 @@
681693 static void cdns_uart_set_termios(struct uart_port *port,
682694 				struct ktermios *termios, struct ktermios *old)
683695 {
684
-	unsigned int cval = 0;
696
+	u32 cval = 0;
685697 	unsigned int baud, minbaud, maxbaud;
686698 	unsigned long flags;
687
-	unsigned int ctrl_reg, mode_reg, val;
688
-	int err;
699
+	unsigned int ctrl_reg, mode_reg;
689700 
690
-	/* Wait for the transmit FIFO to empty before making changes */
691
-	if (!(readl(port->membase + CDNS_UART_CR) &
692
-				CDNS_UART_CR_TX_DIS)) {
693
-		err = readl_poll_timeout(port->membase + CDNS_UART_SR,
694
-					 val, (val & CDNS_UART_SR_TXEMPTY),
695
-					 1000, TX_TIMEOUT);
696
-		if (err) {
697
-			dev_err(port->dev, "timed out waiting for tx empty");
698
-			return;
699
-		}
700
-	}
701701 	spin_lock_irqsave(&port->lock, flags);
702702 
703703 	/* Disable the TX and RX to set baud rate */
....@@ -801,6 +801,13 @@
801801 	}
802802 	cval |= mode_reg & 1;
803803 	writel(cval, port->membase + CDNS_UART_MR);
804
+
805
+	cval = readl(port->membase + CDNS_UART_MODEMCR);
806
+	if (termios->c_cflag & CRTSCTS)
807
+		cval |= CDNS_UART_MODEMCR_FCM;
808
+	else
809
+		cval &= ~CDNS_UART_MODEMCR_FCM;
810
+	writel(cval, port->membase + CDNS_UART_MODEMCR);
804811 
805812 	spin_unlock_irqrestore(&port->lock, flags);
806813 }
....@@ -1004,13 +1011,34 @@
10041011  */
10051012 static unsigned int cdns_uart_get_mctrl(struct uart_port *port)
10061013 {
1007
-	return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
1014
+	u32 val;
1015
+	unsigned int mctrl = 0;
1016
+	struct cdns_uart *cdns_uart_data = port->private_data;
1017
+
1018
+	if (cdns_uart_data->cts_override)
1019
+		return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR;
1020
+
1021
+	val = readl(port->membase + CDNS_UART_MODEMSR);
1022
+	if (val & CDNS_UART_MODEMSR_CTS)
1023
+		mctrl |= TIOCM_CTS;
1024
+	if (val & CDNS_UART_MODEMSR_DSR)
1025
+		mctrl |= TIOCM_DSR;
1026
+	if (val & CDNS_UART_MODEMSR_RI)
1027
+		mctrl |= TIOCM_RNG;
1028
+	if (val & CDNS_UART_MODEMSR_DCD)
1029
+		mctrl |= TIOCM_CAR;
1030
+
1031
+	return mctrl;
10081032 }
10091033 
10101034 static void cdns_uart_set_mctrl(struct uart_port *port, unsigned int mctrl)
10111035 {
10121036 	u32 val;
10131037 	u32 mode_reg;
1038
+	struct cdns_uart *cdns_uart_data = port->private_data;
1039
+
1040
+	if (cdns_uart_data->cts_override)
1041
+		return;
10141042 
10151043 	val = readl(port->membase + CDNS_UART_MODEMCR);
10161044 	mode_reg = readl(port->membase + CDNS_UART_MR);
....@@ -1068,8 +1096,6 @@
10681096 		cpu_relax();
10691097 
10701098 	spin_unlock_irqrestore(&port->lock, flags);
1071
-
1072
-	return;
10731099 }
10741100 #endif
10751101 
....@@ -1109,6 +1135,8 @@
11091135 	.poll_put_char	= cdns_uart_poll_put_char,
11101136 #endif
11111137 };
1138
+
1139
+static struct uart_driver cdns_uart_uart_driver;
11121140 
11131141 #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
11141142 /**
....@@ -1185,7 +1213,7 @@
11851213 				unsigned int count)
11861214 {
11871215 	struct uart_port *port = console_port;
1188
-	unsigned long flags;
1216
+	unsigned long flags = 0;
11891217 	unsigned int imr, ctrl;
11901218 	int locked = 1;
11911219 
....@@ -1210,9 +1238,7 @@
12101238 	writel(ctrl, port->membase + CDNS_UART_CR);
12111239 
12121240 	uart_console_write(port, s, count, cdns_uart_console_putchar);
1213
-	while ((readl(port->membase + CDNS_UART_SR) &
1214
-			(CDNS_UART_SR_TXEMPTY | CDNS_UART_SR_TACTIVE)) !=
1215
-			CDNS_UART_SR_TXEMPTY)
1241
+	while (cdns_uart_tx_empty(port) != TIOCSER_TEMT)
12161242 		cpu_relax();
12171243 
12181244 	/* restore interrupt state */
....@@ -1258,8 +1284,6 @@
12581284 	return uart_set_options(port, co, baud, parity, bits, flow);
12591285 }
12601286 
1261
-static struct uart_driver cdns_uart_uart_driver;
1262
-
12631287 static struct console cdns_uart_console = {
12641288 	.name	= CDNS_UART_TTY_NAME,
12651289 	.write	= cdns_uart_console_write,
....@@ -1271,18 +1295,6 @@
12711295 };
12721296 #endif /* CONFIG_SERIAL_XILINX_PS_UART_CONSOLE */
12731297 
1274
-static struct uart_driver cdns_uart_uart_driver = {
1275
-	.owner		= THIS_MODULE,
1276
-	.driver_name	= CDNS_UART_NAME,
1277
-	.dev_name	= CDNS_UART_TTY_NAME,
1278
-	.major		= CDNS_UART_MAJOR,
1279
-	.minor		= CDNS_UART_MINOR,
1280
-	.nr		= CDNS_UART_NR_PORTS,
1281
-#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
1282
-	.cons		= &cdns_uart_console,
1283
-#endif
1284
-};
1285
-
12861298 #ifdef CONFIG_PM_SLEEP
12871299 /**
12881300  * cdns_uart_suspend - suspend event
....@@ -1293,11 +1305,12 @@
12931305 static int cdns_uart_suspend(struct device *device)
12941306 {
12951307 	struct uart_port *port = dev_get_drvdata(device);
1308
+	struct cdns_uart *cdns_uart = port->private_data;
12961309 	int may_wake;
12971310 
12981311 	may_wake = device_may_wakeup(device);
12991312 
1300
-	if (console_suspend_enabled && may_wake) {
1313
+	if (console_suspend_enabled && uart_console(port) && may_wake) {
13011314 		unsigned long flags = 0;
13021315 
13031316 		spin_lock_irqsave(&port->lock, flags);
....@@ -1316,7 +1329,7 @@
13161329 	 * Call the API provided in serial_core.c file which handles
13171330 	 * the suspend.
13181331 	 */
1319
-	return uart_suspend_port(&cdns_uart_uart_driver, port);
1332
+	return uart_suspend_port(cdns_uart->cdns_uart_driver, port);
13201333 }
13211334 
13221335 /**
....@@ -1328,15 +1341,14 @@
13281341 static int cdns_uart_resume(struct device *device)
13291342 {
13301343 	struct uart_port *port = dev_get_drvdata(device);
1344
+	struct cdns_uart *cdns_uart = port->private_data;
13311345 	unsigned long flags = 0;
13321346 	u32 ctrl_reg;
13331347 	int may_wake;
13341348 
13351349 	may_wake = device_may_wakeup(device);
13361350 
1337
-	if (console_suspend_enabled && !may_wake) {
1338
-		struct cdns_uart *cdns_uart = port->private_data;
1339
-
1351
+	if (console_suspend_enabled && uart_console(port) && !may_wake) {
13401352 		clk_enable(cdns_uart->pclk);
13411353 		clk_enable(cdns_uart->uartclk);
13421354 
....@@ -1370,7 +1382,7 @@
13701382 		spin_unlock_irqrestore(&port->lock, flags);
13711383 	}
13721384 
1373
-	return uart_resume_port(&cdns_uart_uart_driver, port);
1385
+	return uart_resume_port(cdns_uart->cdns_uart_driver, port);
13741386 }
13751387 #endif /* ! CONFIG_PM_SLEEP */
13761388 static int __maybe_unused cdns_runtime_suspend(struct device *dev)
....@@ -1412,6 +1424,9 @@
14121424 };
14131425 MODULE_DEVICE_TABLE(of, cdns_uart_of_match);
14141426 
1427
+/* Temporary variable for storing number of instances */
1428
+static int instances;
1429
+
14151430 /**
14161431  * cdns_uart_probe - Platform driver probe
14171432  * @pdev: Pointer to the platform device structure
....@@ -1434,6 +1449,36 @@
14341449 	if (!port)
14351450 		return -ENOMEM;
14361451 
1452
+	/* Look for a serialN alias */
1453
+	id = of_alias_get_id(pdev->dev.of_node, "serial");
1454
+	if (id < 0)
1455
+		id = 0;
1456
+
1457
+	if (id >= CDNS_UART_NR_PORTS) {
1458
+		dev_err(&pdev->dev, "Cannot get uart_port structure\n");
1459
+		return -ENODEV;
1460
+	}
1461
+
1462
+	if (!cdns_uart_uart_driver.state) {
1463
+		cdns_uart_uart_driver.owner = THIS_MODULE;
1464
+		cdns_uart_uart_driver.driver_name = CDNS_UART_NAME;
1465
+		cdns_uart_uart_driver.dev_name = CDNS_UART_TTY_NAME;
1466
+		cdns_uart_uart_driver.major = CDNS_UART_MAJOR;
1467
+		cdns_uart_uart_driver.minor = CDNS_UART_MINOR;
1468
+		cdns_uart_uart_driver.nr = CDNS_UART_NR_PORTS;
1469
+#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
1470
+		cdns_uart_uart_driver.cons = &cdns_uart_console;
1471
+#endif
1472
+
1473
+		rc = uart_register_driver(&cdns_uart_uart_driver);
1474
+		if (rc < 0) {
1475
+			dev_err(&pdev->dev, "Failed to register driver\n");
1476
+			return rc;
1477
+		}
1478
+	}
1479
+
1480
+	cdns_uart_data->cdns_uart_driver = &cdns_uart_uart_driver;
1481
+
14371482 	match = of_match_node(cdns_uart_of_match, pdev->dev.of_node);
14381483 	if (match && match->data) {
14391484 		const struct cdns_platform_data *data = match->data;
....@@ -1442,31 +1487,39 @@
14421487 	}
14431488 
14441489 	cdns_uart_data->pclk = devm_clk_get(&pdev->dev, "pclk");
1490
+	if (PTR_ERR(cdns_uart_data->pclk) == -EPROBE_DEFER) {
1491
+		rc = PTR_ERR(cdns_uart_data->pclk);
1492
+		goto err_out_unregister_driver;
1493
+	}
1494
+
14451495 	if (IS_ERR(cdns_uart_data->pclk)) {
14461496 		cdns_uart_data->pclk = devm_clk_get(&pdev->dev, "aper_clk");
1447
-		if (!IS_ERR(cdns_uart_data->pclk))
1448
-			dev_err(&pdev->dev, "clock name 'aper_clk' is deprecated.\n");
1449
-	}
1450
-	if (IS_ERR(cdns_uart_data->pclk)) {
1451
-		dev_err(&pdev->dev, "pclk clock not found.\n");
1452
-		return PTR_ERR(cdns_uart_data->pclk);
1497
+		if (IS_ERR(cdns_uart_data->pclk)) {
1498
+			rc = PTR_ERR(cdns_uart_data->pclk);
1499
+			goto err_out_unregister_driver;
1500
+		}
1501
+		dev_err(&pdev->dev, "clock name 'aper_clk' is deprecated.\n");
14531502 	}
14541503 
14551504 	cdns_uart_data->uartclk = devm_clk_get(&pdev->dev, "uart_clk");
1505
+	if (PTR_ERR(cdns_uart_data->uartclk) == -EPROBE_DEFER) {
1506
+		rc = PTR_ERR(cdns_uart_data->uartclk);
1507
+		goto err_out_unregister_driver;
1508
+	}
1509
+
14561510 	if (IS_ERR(cdns_uart_data->uartclk)) {
14571511 		cdns_uart_data->uartclk = devm_clk_get(&pdev->dev, "ref_clk");
1458
-		if (!IS_ERR(cdns_uart_data->uartclk))
1459
-			dev_err(&pdev->dev, "clock name 'ref_clk' is deprecated.\n");
1460
-	}
1461
-	if (IS_ERR(cdns_uart_data->uartclk)) {
1462
-		dev_err(&pdev->dev, "uart_clk clock not found.\n");
1463
-		return PTR_ERR(cdns_uart_data->uartclk);
1512
+		if (IS_ERR(cdns_uart_data->uartclk)) {
1513
+			rc = PTR_ERR(cdns_uart_data->uartclk);
1514
+			goto err_out_unregister_driver;
1515
+		}
1516
+		dev_err(&pdev->dev, "clock name 'ref_clk' is deprecated.\n");
14641517 	}
14651518 
14661519 	rc = clk_prepare_enable(cdns_uart_data->pclk);
14671520 	if (rc) {
14681521 		dev_err(&pdev->dev, "Unable to enable pclk clock.\n");
1469
-		return rc;
1522
+		goto err_out_unregister_driver;
14701523 	}
14711524 	rc = clk_prepare_enable(cdns_uart_data->uartclk);
14721525 	if (rc) {
....@@ -1493,28 +1546,16 @@
14931546 				&cdns_uart_data->clk_rate_change_nb))
14941547 		dev_warn(&pdev->dev, "Unable to register clock notifier.\n");
14951548 #endif
1496
-	/* Look for a serialN alias */
1497
-	id = of_alias_get_id(pdev->dev.of_node, "serial");
1498
-	if (id < 0)
1499
-		id = 0;
1500
-
1501
-	if (id >= CDNS_UART_NR_PORTS) {
1502
-		dev_err(&pdev->dev, "Cannot get uart_port structure\n");
1503
-		rc = -ENODEV;
1504
-		goto err_out_notif_unreg;
1505
-	}
15061549 
15071550 	/* At this point, we've got an empty uart_port struct, initialize it */
15081551 	spin_lock_init(&port->lock);
1509
-	port->membase	= NULL;
1510
-	port->irq	= 0;
15111552 	port->type	= PORT_UNKNOWN;
15121553 	port->iotype	= UPIO_MEM32;
15131554 	port->flags	= UPF_BOOT_AUTOCONF;
15141555 	port->ops	= &cdns_uart_ops;
15151556 	port->fifosize	= CDNS_UART_FIFO_SIZE;
1557
+	port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_XILINX_PS_UART_CONSOLE);
15161558 	port->line	= id;
1517
-	port->dev	= NULL;
15181559 
15191560 	/*
15201561 	 * Register the port.
....@@ -1533,6 +1574,7 @@
15331574 	pm_runtime_set_autosuspend_delay(&pdev->dev, UART_AUTOSUSPEND_TIMEOUT);
15341575 	pm_runtime_set_active(&pdev->dev);
15351576 	pm_runtime_enable(&pdev->dev);
1577
+	device_init_wakeup(port->dev, true);
15361578 
15371579 #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
15381580 	/*
....@@ -1541,8 +1583,10 @@
15411583 	 * If register_console() don't assign value, then console_port pointer
15421584 	 * is cleanup.
15431585 	 */
1544
-	if (cdns_uart_uart_driver.cons->index == -1)
1586
+	if (!console_port) {
1587
+		cdns_uart_console.index = id;
15451588 		console_port = port;
1589
+	}
15461590 #endif
15471591 
15481592 	rc = uart_add_one_port(&cdns_uart_uart_driver, port);
....@@ -1554,9 +1598,17 @@
15541598 
15551599 #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
15561600 	/* This is not port which is used for console that's why clean it up */
1557
-	if (cdns_uart_uart_driver.cons->index == -1)
1601
+	if (console_port == port &&
1602
+	    !(cdns_uart_uart_driver.cons->flags & CON_ENABLED)) {
15581603 		console_port = NULL;
1604
+		cdns_uart_console.index = -1;
1605
+	}
15591606 #endif
1607
+
1608
+	cdns_uart_data->cts_override = of_property_read_bool(pdev->dev.of_node,
1609
+							     "cts-override");
1610
+
1611
+	instances++;
15601612 
15611613 	return 0;
15621614 
....@@ -1564,7 +1616,6 @@
15641616 	pm_runtime_disable(&pdev->dev);
15651617 	pm_runtime_set_suspended(&pdev->dev);
15661618 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1567
-err_out_notif_unreg:
15681619 #ifdef CONFIG_COMMON_CLK
15691620 	clk_notifier_unregister(cdns_uart_data->uartclk,
15701621 			&cdns_uart_data->clk_rate_change_nb);
....@@ -1573,7 +1624,9 @@
15731624 	clk_disable_unprepare(cdns_uart_data->uartclk);
15741625 err_out_clk_dis_pclk:
15751626 	clk_disable_unprepare(cdns_uart_data->pclk);
1576
-
1627
+err_out_unregister_driver:
1628
+	if (!instances)
1629
+		uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
15771630 	return rc;
15781631 }
15791632 
....@@ -1594,13 +1647,22 @@
15941647 	clk_notifier_unregister(cdns_uart_data->uartclk,
15951648 			&cdns_uart_data->clk_rate_change_nb);
15961649 #endif
1597
-	rc = uart_remove_one_port(&cdns_uart_uart_driver, port);
1650
+	rc = uart_remove_one_port(cdns_uart_data->cdns_uart_driver, port);
15981651 	port->mapbase = 0;
15991652 	clk_disable_unprepare(cdns_uart_data->uartclk);
16001653 	clk_disable_unprepare(cdns_uart_data->pclk);
16011654 	pm_runtime_disable(&pdev->dev);
16021655 	pm_runtime_set_suspended(&pdev->dev);
16031656 	pm_runtime_dont_use_autosuspend(&pdev->dev);
1657
+	device_init_wakeup(&pdev->dev, false);
1658
+
1659
+#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE
1660
+	if (console_port == port)
1661
+		console_port = NULL;
1662
+#endif
1663
+
1664
+	if (!--instances)
1665
+		uart_unregister_driver(cdns_uart_data->cdns_uart_driver);
16041666 	return rc;
16051667 }
16061668 
....@@ -1617,28 +1679,14 @@
16171679 
16181680 static int __init cdns_uart_init(void)
16191681 {
1620
-	int retval = 0;
1621
-
1622
-	/* Register the cdns_uart driver with the serial core */
1623
-	retval = uart_register_driver(&cdns_uart_uart_driver);
1624
-	if (retval)
1625
-		return retval;
1626
-
16271682 	/* Register the platform driver */
1628
-	retval = platform_driver_register(&cdns_uart_platform_driver);
1629
-	if (retval)
1630
-		uart_unregister_driver(&cdns_uart_uart_driver);
1631
-
1632
-	return retval;
1683
+	return platform_driver_register(&cdns_uart_platform_driver);
16331684 }
16341685 
16351686 static void __exit cdns_uart_exit(void)
16361687 {
16371688 	/* Unregister the platform driver */
16381689 	platform_driver_unregister(&cdns_uart_platform_driver);
1639
-
1640
-	/* Unregister the cdns_uart driver */
1641
-	uart_unregister_driver(&cdns_uart_uart_driver);
16421690 }
16431691 
16441692 arch_initcall(cdns_uart_init);