TTY / Serial driver fixes for 5.13-rc4

Here are some small fixes for reported problems for tty and serial
 drivers for 5.13-rc4.
 
 They consist of:
 	- 8250 bugfixes and new device support
 	- lockdown security mode fixup
 	- syzbot found problems fixed
 	- 8250_omap fix for interrupt storm
 	- revert of 8250_omap driver fix as it caused worse problem than
 	  the original issue
 
 All but the last patch have been in linux-next for a while, the last one
 is a revert of a problem found in linux-next with the 8250_omap driver
 change.
 
 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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Merge tag 'tty-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial driver fixes from Greg KH:
 "Here are some small fixes for reported problems for tty and serial
  drivers for 5.13-rc4.

  They consist of:

   - 8250 bugfixes and new device support

   - lockdown security mode fixup

   - syzbot found problems fixed

   - 8250_omap fix for interrupt storm

   - revert of 8250_omap driver fix as it caused worse problem than the
     original issue

  All but the last patch have been in linux-next for a while, the last
  one is a revert of a problem found in linux-next with the 8250_omap
  driver change"

* tag 'tty-5.13-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  Revert "serial: 8250: 8250_omap: Fix possible interrupt storm"
  serial: 8250_pci: handle FL_NOIRQ board flag
  serial: rp2: use 'request_firmware' instead of 'request_firmware_nowait'
  serial: 8250_pci: Add support for new HPE serial device
  serial: 8250: 8250_omap: Fix possible interrupt storm
  serial: 8250: Use BIT(x) for UART_{CAP,BUG}_*
  serial: 8250: Add UART_BUG_TXRACE workaround for Aspeed VUART
  serial: 8250_dw: Add device HID for new AMD UART controller
  serial: sh-sci: Fix off-by-one error in FIFO threshold register setting
  serial: core: fix suspicious security_locked_down() call
  serial: tegra: Fix a mask operation that is always true

drivers/acpi/acpi_apd.c

@@ -226,6 +226,7 @@ static const struct acpi_device_id acpi_apd_device_ids[] = {
 	{ "AMDI0010", APD_ADDR(wt_i2c_desc) },
 	{ "AMD0020", APD_ADDR(cz_uart_desc) },
 	{ "AMDI0020", APD_ADDR(cz_uart_desc) },
+	{ "AMDI0022", APD_ADDR(cz_uart_desc) },
 	{ "AMD0030", },
 	{ "AMD0040", APD_ADDR(fch_misc_desc)},
 	{ "HYGO0010", APD_ADDR(wt_i2c_desc) },

drivers/tty/serial/8250/8250.h

@@ -7,6 +7,7 @@
  *  Copyright (C) 2001 Russell King.
  */
 
+#include <linux/bits.h>
 #include <linux/serial_8250.h>
 #include <linux/serial_reg.h>
 #include <linux/dmaengine.h>
@@ -70,24 +71,25 @@ struct serial8250_config {
 	unsigned int	flags;
 };
 
-#define UART_CAP_FIFO	(1 << 8)	/* UART has FIFO */
+#define UART_CAP_FIFO	BIT(8)	/* UART has FIFO */
-#define UART_CAP_EFR	(1 << 9)	/* UART has EFR */
+#define UART_CAP_EFR	BIT(9)	/* UART has EFR */
-#define UART_CAP_SLEEP	(1 << 10)	/* UART has IER sleep */
+#define UART_CAP_SLEEP	BIT(10)	/* UART has IER sleep */
-#define UART_CAP_AFE	(1 << 11)	/* MCR-based hw flow control */
+#define UART_CAP_AFE	BIT(11)	/* MCR-based hw flow control */
-#define UART_CAP_UUE	(1 << 12)	/* UART needs IER bit 6 set (Xscale) */
+#define UART_CAP_UUE	BIT(12)	/* UART needs IER bit 6 set (Xscale) */
-#define UART_CAP_RTOIE	(1 << 13)	/* UART needs IER bit 4 set (Xscale, Tegra) */
+#define UART_CAP_RTOIE	BIT(13)	/* UART needs IER bit 4 set (Xscale, Tegra) */
-#define UART_CAP_HFIFO	(1 << 14)	/* UART has a "hidden" FIFO */
+#define UART_CAP_HFIFO	BIT(14)	/* UART has a "hidden" FIFO */
-#define UART_CAP_RPM	(1 << 15)	/* Runtime PM is active while idle */
+#define UART_CAP_RPM	BIT(15)	/* Runtime PM is active while idle */
-#define UART_CAP_IRDA	(1 << 16)	/* UART supports IrDA line discipline */
+#define UART_CAP_IRDA	BIT(16)	/* UART supports IrDA line discipline */
-#define UART_CAP_MINI	(1 << 17)	/* Mini UART on BCM283X family lacks:
+#define UART_CAP_MINI	BIT(17)	/* Mini UART on BCM283X family lacks:
 					 * STOP PARITY EPAR SPAR WLEN5 WLEN6
 					 */
 
-#define UART_BUG_QUOT	(1 << 0)	/* UART has buggy quot LSB */
+#define UART_BUG_QUOT	BIT(0)	/* UART has buggy quot LSB */
-#define UART_BUG_TXEN	(1 << 1)	/* UART has buggy TX IIR status */
+#define UART_BUG_TXEN	BIT(1)	/* UART has buggy TX IIR status */
-#define UART_BUG_NOMSR	(1 << 2)	/* UART has buggy MSR status bits (Au1x00) */
+#define UART_BUG_NOMSR	BIT(2)	/* UART has buggy MSR status bits (Au1x00) */
-#define UART_BUG_THRE	(1 << 3)	/* UART has buggy THRE reassertion */
+#define UART_BUG_THRE	BIT(3)	/* UART has buggy THRE reassertion */
-#define UART_BUG_PARITY	(1 << 4)	/* UART mishandles parity if FIFO enabled */
+#define UART_BUG_PARITY	BIT(4)	/* UART mishandles parity if FIFO enabled */
+#define UART_BUG_TXRACE	BIT(5)	/* UART Tx fails to set remote DR */
 
 
 #ifdef CONFIG_SERIAL_8250_SHARE_IRQ

drivers/tty/serial/8250/8250_aspeed_vuart.c

@@ -437,6 +437,7 @@ static int aspeed_vuart_probe(struct platform_device *pdev)
 	port.port.status = UPSTAT_SYNC_FIFO;
 	port.port.dev = &pdev->dev;
 	port.port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_8250_CONSOLE);
+	port.bugs |= UART_BUG_TXRACE;
 
 	rc = sysfs_create_group(&vuart->dev->kobj, &aspeed_vuart_attr_group);
 	if (rc < 0)

drivers/tty/serial/8250/8250_dw.c

@@ -714,6 +714,7 @@ static const struct acpi_device_id dw8250_acpi_match[] = {
 	{ "APMC0D08", 0},
 	{ "AMD0020", 0 },
 	{ "AMDI0020", 0 },
+	{ "AMDI0022", 0 },
 	{ "BRCM2032", 0 },
 	{ "HISI0031", 0 },
 	{ },

drivers/tty/serial/8250/8250_pci.c

@@ -56,6 +56,8 @@ struct serial_private {
 	int			line[];
 };
 
+#define PCI_DEVICE_ID_HPE_PCI_SERIAL	0x37e
+
 static const struct pci_device_id pci_use_msi[] = {
 	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_NETMOS, PCI_DEVICE_ID_NETMOS_9900,
 			 0xA000, 0x1000) },
@@ -63,6 +65,8 @@ static const struct pci_device_id pci_use_msi[] = {
 			 0xA000, 0x1000) },
 	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_NETMOS, PCI_DEVICE_ID_NETMOS_9922,
 			 0xA000, 0x1000) },
+	{ PCI_DEVICE_SUB(PCI_VENDOR_ID_HP_3PAR, PCI_DEVICE_ID_HPE_PCI_SERIAL,
+			 PCI_ANY_ID, PCI_ANY_ID) },
 	{ }
 };
 
@@ -1997,6 +2001,16 @@ static struct pci_serial_quirk pci_serial_quirks[] = {
 		.init		= pci_hp_diva_init,
 		.setup		= pci_hp_diva_setup,
 	},
+	/*
+	 * HPE PCI serial device
+	 */
+	{
+		.vendor         = PCI_VENDOR_ID_HP_3PAR,
+		.device         = PCI_DEVICE_ID_HPE_PCI_SERIAL,
+		.subvendor      = PCI_ANY_ID,
+		.subdevice      = PCI_ANY_ID,
+		.setup		= pci_hp_diva_setup,
+	},
 	/*
 	 * Intel
 	 */
@@ -3944,6 +3958,9 @@ pciserial_init_ports(struct pci_dev *dev, const struct pciserial_board *board)
 	uart.port.flags = UPF_SKIP_TEST | UPF_BOOT_AUTOCONF | UPF_SHARE_IRQ;
 	uart.port.uartclk = board->base_baud * 16;
 
+	if (board->flags & FL_NOIRQ) {
+		uart.port.irq = 0;
+	} else {
 		if (pci_match_id(pci_use_msi, dev)) {
 			dev_dbg(&dev->dev, "Using MSI(-X) interrupts\n");
 			pci_set_master(dev);
@@ -3959,6 +3976,8 @@ pciserial_init_ports(struct pci_dev *dev, const struct pciserial_board *board)
 		}
 
 		uart.port.irq = pci_irq_vector(dev, 0);
+	}
+
 	uart.port.dev = &dev->dev;
 
 	for (i = 0; i < nr_ports; i++) {
@@ -4973,6 +4992,10 @@ static const struct pci_device_id serial_pci_tbl[] = {
 	{	PCI_VENDOR_ID_HP, PCI_DEVICE_ID_HP_DIVA_AUX,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
 		pbn_b2_1_115200 },
+	/* HPE PCI serial device */
+	{	PCI_VENDOR_ID_HP_3PAR, PCI_DEVICE_ID_HPE_PCI_SERIAL,
+		PCI_ANY_ID, PCI_ANY_ID, 0, 0,
+		pbn_b1_1_115200 },
 
 	{	PCI_VENDOR_ID_DCI, PCI_DEVICE_ID_DCI_PCCOM2,
 		PCI_ANY_ID, PCI_ANY_ID, 0, 0,

drivers/tty/serial/8250/8250_port.c

@@ -1809,6 +1809,18 @@ void serial8250_tx_chars(struct uart_8250_port *up)
 	count = up->tx_loadsz;
 	do {
 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
+		if (up->bugs & UART_BUG_TXRACE) {
+			/*
+			 * The Aspeed BMC virtual UARTs have a bug where data
+			 * may get stuck in the BMC's Tx FIFO from bursts of
+			 * writes on the APB interface.
+			 *
+			 * Delay back-to-back writes by a read cycle to avoid
+			 * stalling the VUART. Read a register that won't have
+			 * side-effects and discard the result.
+			 */
+			serial_in(up, UART_SCR);
+		}
 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
 		port->icount.tx++;
 		if (uart_circ_empty(xmit))

drivers/tty/serial/rp2.c

@@ -195,7 +195,6 @@ struct rp2_card {
 	void __iomem			*bar0;
 	void __iomem			*bar1;
 	spinlock_t			card_lock;
-	struct completion		fw_loaded;
 };
 
 #define RP_ID(prod) PCI_VDEVICE(RP, (prod))
@@ -662,17 +661,10 @@ static void rp2_remove_ports(struct rp2_card *card)
 	card->initialized_ports = 0;
 }
 
-static void rp2_fw_cb(const struct firmware *fw, void *context)
+static int rp2_load_firmware(struct rp2_card *card, const struct firmware *fw)
 {
-	struct rp2_card *card = context;
 	resource_size_t phys_base;
-	int i, rc = -ENOENT;
+	int i, rc = 0;
-
-	if (!fw) {
-		dev_err(&card->pdev->dev, "cannot find '%s' firmware image\n",
-			RP2_FW_NAME);
-		goto no_fw;
-	}
 
 	phys_base = pci_resource_start(card->pdev, 1);
 
@@ -718,23 +710,13 @@ static void rp2_fw_cb(const struct firmware *fw, void *context)
 		card->initialized_ports++;
 	}
 
-	release_firmware(fw);
+	return rc;
-no_fw:
-	/*
-	 * rp2_fw_cb() is called from a workqueue long after rp2_probe()
-	 * has already returned success.  So if something failed here,
-	 * we'll just leave the now-dormant device in place until somebody
-	 * unbinds it.
-	 */
-	if (rc)
-		dev_warn(&card->pdev->dev, "driver initialization failed\n");
-
-	complete(&card->fw_loaded);
 }
 
 static int rp2_probe(struct pci_dev *pdev,
 				   const struct pci_device_id *id)
 {
+	const struct firmware *fw;
 	struct rp2_card *card;
 	struct rp2_uart_port *ports;
 	void __iomem * const *bars;
@@ -745,7 +727,6 @@ static int rp2_probe(struct pci_dev *pdev,
 		return -ENOMEM;
 	pci_set_drvdata(pdev, card);
 	spin_lock_init(&card->card_lock);
-	init_completion(&card->fw_loaded);
 
 	rc = pcim_enable_device(pdev);
 	if (rc)
@@ -778,22 +759,24 @@ static int rp2_probe(struct pci_dev *pdev,
 		return -ENOMEM;
 	card->ports = ports;
 
+	rc = request_firmware(&fw, RP2_FW_NAME, &pdev->dev);
+	if (rc < 0) {
+		dev_err(&pdev->dev, "cannot find '%s' firmware image\n",
+			RP2_FW_NAME);
+		return rc;
+	}
+
+	rc = rp2_load_firmware(card, fw);
+
+	release_firmware(fw);
+	if (rc < 0)
+		return rc;
+
 	rc = devm_request_irq(&pdev->dev, pdev->irq, rp2_uart_interrupt,
 			      IRQF_SHARED, DRV_NAME, card);
 	if (rc)
 		return rc;
 
-	/*
-	 * Only catastrophic errors (e.g. ENOMEM) are reported here.
-	 * If the FW image is missing, we'll find out in rp2_fw_cb()
-	 * and print an error message.
-	 */
-	rc = request_firmware_nowait(THIS_MODULE, 1, RP2_FW_NAME, &pdev->dev,
-				     GFP_KERNEL, card, rp2_fw_cb);
-	if (rc)
-		return rc;
-	dev_dbg(&pdev->dev, "waiting for firmware blob...\n");
-
 	return 0;
 }
 
@@ -801,7 +784,6 @@ static void rp2_remove(struct pci_dev *pdev)
 {
 	struct rp2_card *card = pci_get_drvdata(pdev);
 
-	wait_for_completion(&card->fw_loaded);
 	rp2_remove_ports(card);
 }
 

drivers/tty/serial/serial-tegra.c

@@ -338,7 +338,7 @@ static void tegra_uart_fifo_reset(struct tegra_uart_port *tup, u8 fcr_bits)
 
 	do {
 		lsr = tegra_uart_read(tup, UART_LSR);
-		if ((lsr | UART_LSR_TEMT) && !(lsr & UART_LSR_DR))
+		if ((lsr & UART_LSR_TEMT) && !(lsr & UART_LSR_DR))
 			break;
 		udelay(1);
 	} while (--tmout);

drivers/tty/serial/serial_core.c

@@ -863,9 +863,11 @@ static int uart_set_info(struct tty_struct *tty, struct tty_port *port,
 		goto check_and_exit;
 	}
 
+	if (change_irq || change_port) {
 		retval = security_locked_down(LOCKDOWN_TIOCSSERIAL);
-	if (retval && (change_irq || change_port))
+		if (retval)
 			goto exit;
+	}
 
 	/*
 	 * Ask the low level driver to verify the settings.

drivers/tty/serial/sh-sci.c

@@ -1023,10 +1023,10 @@ static int scif_set_rtrg(struct uart_port *port, int rx_trig)
 {
 	unsigned int bits;
 
+	if (rx_trig >= port->fifosize)
+		rx_trig = port->fifosize - 1;
 	if (rx_trig < 1)
 		rx_trig = 1;
-	if (rx_trig >= port->fifosize)
-		rx_trig = port->fifosize;
 
 	/* HSCIF can be set to an arbitrary level. */
 	if (sci_getreg(port, HSRTRGR)->size) {