Merge tag 'tty-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial fixes from Greg KH:
 "Here are some small tty/serial/vt fixes for 7.2-rc3 that resolve some
  reported problems. Included in here are:

   - vt spurious modifier issue that showed up in -rc1 (reported a
     bunch)

   - 8250 driver bugfixes

   - msm serial driver bugfix

   - max310x serial driver bugfix

  All of these have been in linux-next with no reported issues"

* tag 'tty-7.2-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty:
  serial: 8250: Ignore flow control on suspend/resume with no_console_suspend
  serial: 8250_mid: Disable DMA for selected platforms
  serial: 8250_omap: clear rx_running on zero-length DMA completes
  vt: fix spurious modifier in CSI/cursor key sequences
  serial: msm: Disable DMA for kernel console UART
  serial: max310x: implement gpio_chip::get_direction()

Author: torvalds

drivers/tty/serial/8250/8250_mid.c

@@ -10,6 +10,7 @@
 #include <linux/module.h>
 #include <linux/pci.h>
 #include <linux/rational.h>
+#include <linux/util_macros.h>
 
 #include <linux/dma/hsu.h>
 
@@ -368,8 +369,16 @@ static const struct mid8250_board dnv_board = {
 	.freq = 133333333,
 	.base_baud = 115200,
 	.bar = 1,
-	.setup = dnv_setup,
-	.exit = dnv_exit,
+	/*
+	 * Errata:
+	 * HSUART May Stop Functioning when DMA is Active.
+	 *
+	 * - Denverton document #572409, rev 3.4, DNV60
+	 * - Ice Lake Xeon D document #714070, ICXD65
+	 * - Snowridge document #731931, SNR44
+	 */
+	.setup = PTR_IF(false, dnv_setup),
+	.exit = PTR_IF(false, dnv_exit),
 };
 
 static const struct pci_device_id pci_ids[] = {

drivers/tty/serial/8250/8250_omap.c

@@ -944,11 +944,12 @@ static void __dma_rx_do_complete(struct uart_8250_port *p)
 				dev_err(p->port.dev, "teardown incomplete\n");
 		}
 	}
+
+	dma->rx_running = 0;
 	if (!count)
 		goto out;
 	ret = tty_insert_flip_string(tty_port, dma->rx_buf, count);
 
-	dma->rx_running = 0;
 	p->port.icount.rx += ret;
 	p->port.icount.buf_overrun += count - ret;
 out:

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

@@ -2000,8 +2000,14 @@ static void wait_for_xmitr(struct uart_8250_port *up, int bits)
 
 	tx_ready = wait_for_lsr(up, bits);
 
-	/* Wait up to 1s for flow control if necessary */
-	if (uart_console_hwflow_active(&up->port)) {
+	/*
+	 * Wait up to 1s for flow control if necessary.
+	 * When 'no_console_suspend' is active (in the window between
+	 * suspend() and resume()), flow control is temporarily ignored
+	 * because the canary workaround is not reliable in all situations,
+	 * leading to flow control timeouts for every character.
+	 */
+	if (uart_console_hwflow_active(&up->port) && !up->canary) {
 		for (tmout = 1000000; tmout; tmout--) {
 			unsigned int msr = serial_in(up, UART_MSR);
 			up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;

drivers/tty/serial/max310x.c

@@ -1243,6 +1243,17 @@ static int max310x_gpio_set(struct gpio_chip *chip, unsigned int offset,
 	return 0;
 }
 
+static int max310x_gpio_get_direction(struct gpio_chip *chip, unsigned int offset)
+{
+	struct max310x_port *s = gpiochip_get_data(chip);
+	struct uart_port *port = &s->p[offset / 4].port;
+	unsigned int val;
+
+	val = max310x_port_read(port, MAX310X_GPIOCFG_REG);
+
+	return val & BIT(offset % 4) ? GPIO_LINE_DIRECTION_OUT : GPIO_LINE_DIRECTION_IN;
+}
+
 static int max310x_gpio_direction_input(struct gpio_chip *chip, unsigned int offset)
 {
 	struct max310x_port *s = gpiochip_get_data(chip);
@@ -1446,6 +1457,7 @@ static int max310x_probe(struct device *dev, const struct max310x_devtype *devty
 	s->gpio.owner		= THIS_MODULE;
 	s->gpio.parent		= dev;
 	s->gpio.label		= devtype->name;
+	s->gpio.get_direction	= max310x_gpio_get_direction;
 	s->gpio.direction_input	= max310x_gpio_direction_input;
 	s->gpio.get		= max310x_gpio_get;
 	s->gpio.direction_output= max310x_gpio_direction_output;

drivers/tty/serial/msm_serial.c

@@ -1228,7 +1228,8 @@ static int msm_startup(struct uart_port *port)
 	data |= MSM_UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
 	msm_write(port, data, MSM_UART_MR1);
 
-	if (msm_port->is_uartdm) {
+	/* Disable DMA for console to prevent PIO/DMA collisions */
+	if (msm_port->is_uartdm && !uart_console(port)) {
 		msm_request_tx_dma(msm_port, msm_port->uart.mapbase);
 		msm_request_rx_dma(msm_port, msm_port->uart.mapbase);
 	}

drivers/tty/vt/keyboard.c

@@ -765,16 +765,22 @@ static void k_fn(struct vc_data *vc, unsigned char value, char up_flag)
 /*
  * Compute xterm-style modifier parameter for CSI sequences.
  * Returns 1 + (shift ? 1 : 0) + (alt ? 2 : 0) + (ctrl ? 4 : 0)
+ *
+ * Only the canonical modifier weights are counted. The left/right variants
+ * (KG_SHIFTL, KG_SHIFTR, KG_CTRLL, KG_CTRLR) and KG_ALTGR are commonly
+ * repurposed as keymap layout-group or level selectors rather than as plain
+ * modifiers (for instance XKB-derived keymaps select the layout group with
+ * KG_SHIFTL/KG_SHIFTR), so counting them would encode a spurious modifier.
  */
 static int csi_modifier_param(void)
 {
 	int mod = 1;
 
-	if (shift_state & (BIT(KG_SHIFT) | BIT(KG_SHIFTL) | BIT(KG_SHIFTR)))
+	if (shift_state & BIT(KG_SHIFT))
 		mod += 1;
-	if (shift_state & (BIT(KG_ALT) | BIT(KG_ALTGR)))
+	if (shift_state & BIT(KG_ALT))
 		mod += 2;
-	if (shift_state & (BIT(KG_CTRL) | BIT(KG_CTRLL) | BIT(KG_CTRLR)))
+	if (shift_state & BIT(KG_CTRL))
 		mod += 4;
 	return mod;
 }