Merge tag 'tty-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial updates from Greg KH:
 "Here is the "big" tty and serial driver patches for 5.5-rc1.

  It's a bit later in the merge window than normal as I wanted to make
  sure some last-minute patches applied to it were all sane. They seem
  to be :)

  There's a lot of little stuff in here, for the tty core, and for lots
  of serial drivers:

   - reverts of uartlite serial driver patches that were wrong

   - msm-serial driver fixes

   - serial core updates and fixes

   - tty core fixes

   - serial driver dma mapping api changes

   - lots of other tiny fixes and updates for serial drivers

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

* tag 'tty-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (58 commits)
  Revert "serial/8250: Add support for NI-Serial PXI/PXIe+485 devices"
  vcs: prevent write access to vcsu devices
  tty: vt: keyboard: reject invalid keycodes
  tty: don't crash in tty_init_dev when missing tty_port
  serial: stm32: fix clearing interrupt error flags
  tty: Fix Kconfig indentation, continued
  serial: serial_core: Perform NULL checks for break_ctl ops
  tty: remove unused argument from tty_open_by_driver()
  tty: Fix Kconfig indentation
  {tty: serial, nand: onenand}: samsung: rename to fix build warning
  serial: ifx6x60: add missed pm_runtime_disable
  serial: pl011: Fix DMA ->flush_buffer()
  Revert "serial-uartlite: Move the uart register"
  Revert "serial-uartlite: Add get serial id if not provided"
  Revert "serial-uartlite: Do not use static struct uart_driver out of probe()"
  Revert "serial-uartlite: Add runtime support"
  Revert "serial-uartlite: Change logic how console_port is setup"
  Revert "serial-uartlite: Use allocated structure instead of static ones"
  tty: serial: msm_serial: Use dma_request_chan() directly for channel request
  tty: serial: tegra: Use dma_request_chan() directly for channel request
  ...

1 files changed, 84 insertions, 0 deletions

diff --git a/drivers/tty/serial/8250/8250_aspeed_vuart.c b/drivers/tty/serial/8250/8250_aspeed_vuart.c
index 0438d9a905ce..6e67fd89445a 100644
--- a/drivers/tty/serial/8250/8250_aspeed_vuart.c
+++ b/drivers/tty/serial/8250/8250_aspeed_vuart.c
@@ -14,6 +14,8 @@
 #include <linux/of_address.h>
 #include <linux/of_irq.h>
 #include <linux/of_platform.h>
+#include <linux/regmap.h>
+#include <linux/mfd/syscon.h>
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 #include <linux/clk.h>
@@ -22,6 +24,7 @@
 
 #define ASPEED_VUART_GCRA		0x20
 #define ASPEED_VUART_GCRA_VUART_EN		BIT(0)
+#define ASPEED_VUART_GCRA_HOST_SIRQ_POLARITY	BIT(1)
 #define ASPEED_VUART_GCRA_DISABLE_HOST_TX_DISCARD BIT(5)
 #define ASPEED_VUART_GCRB		0x24
 #define ASPEED_VUART_GCRB_HOST_SIRQ_MASK	GENMASK(7, 4)
@@ -131,8 +134,53 @@ static ssize_t sirq_store(struct device *dev, struct device_attribute *attr,
 
 static DEVICE_ATTR_RW(sirq);
 
+static ssize_t sirq_polarity_show(struct device *dev,
+				  struct device_attribute *attr, char *buf)
+{
+	struct aspeed_vuart *vuart = dev_get_drvdata(dev);
+	u8 reg;
+
+	reg = readb(vuart->regs + ASPEED_VUART_GCRA);
+	reg &= ASPEED_VUART_GCRA_HOST_SIRQ_POLARITY;
+
+	return snprintf(buf, PAGE_SIZE - 1, "%u\n", reg ? 1 : 0);
+}
+
+static void aspeed_vuart_set_sirq_polarity(struct aspeed_vuart *vuart,
+					   bool polarity)
+{
+	u8 reg = readb(vuart->regs + ASPEED_VUART_GCRA);
+
+	if (polarity)
+		reg |= ASPEED_VUART_GCRA_HOST_SIRQ_POLARITY;
+	else
+		reg &= ~ASPEED_VUART_GCRA_HOST_SIRQ_POLARITY;
+
+	writeb(reg, vuart->regs + ASPEED_VUART_GCRA);
+}
+
+static ssize_t sirq_polarity_store(struct device *dev,
+				   struct device_attribute *attr,
+				   const char *buf, size_t count)
+{
+	struct aspeed_vuart *vuart = dev_get_drvdata(dev);
+	unsigned long val;
+	int err;
+
+	err = kstrtoul(buf, 0, &val);
+	if (err)
+		return err;
+
+	aspeed_vuart_set_sirq_polarity(vuart, val != 0);
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(sirq_polarity);
+
 static struct attribute *aspeed_vuart_attrs[] = {
 	&dev_attr_sirq.attr,
+	&dev_attr_sirq_polarity.attr,
 	&dev_attr_lpc_address.attr,
 	NULL,
 };
@@ -302,8 +350,30 @@ static int aspeed_vuart_handle_irq(struct uart_port *port)
 	return 1;
 }
 
+static void aspeed_vuart_auto_configure_sirq_polarity(
+	struct aspeed_vuart *vuart, struct device_node *syscon_np,
+	u32 reg_offset, u32 reg_mask)
+{
+	struct regmap *regmap;
+	u32 value;
+
+	regmap = syscon_node_to_regmap(syscon_np);
+	if (IS_ERR(regmap)) {
+		dev_warn(vuart->dev,
+			 "could not get regmap for aspeed,sirq-polarity-sense\n");
+		return;
+	}
+	if (regmap_read(regmap, reg_offset, &value)) {
+		dev_warn(vuart->dev, "could not read hw strap table\n");
+		return;
+	}
+
+	aspeed_vuart_set_sirq_polarity(vuart, (value & reg_mask) == 0);
+}
+
 static int aspeed_vuart_probe(struct platform_device *pdev)
 {
+	struct of_phandle_args sirq_polarity_sense_args;
 	struct uart_8250_port port;
 	struct aspeed_vuart *vuart;
 	struct device_node *np;
@@ -402,6 +472,20 @@ static int aspeed_vuart_probe(struct platform_device *pdev)
 
 	vuart->line = rc;
 
+	rc = of_parse_phandle_with_fixed_args(
+		np, "aspeed,sirq-polarity-sense", 2, 0,
+		&sirq_polarity_sense_args);
+	if (rc < 0) {
+		dev_dbg(&pdev->dev,
+			"aspeed,sirq-polarity-sense property not found\n");
+	} else {
+		aspeed_vuart_auto_configure_sirq_polarity(
+			vuart, sirq_polarity_sense_args.np,
+			sirq_polarity_sense_args.args[0],
+			BIT(sirq_polarity_sense_args.args[1]));
+		of_node_put(sirq_polarity_sense_args.np);
+	}
+
 	aspeed_vuart_set_enabled(vuart, true);
 	aspeed_vuart_set_host_tx_discard(vuart, true);
 	platform_set_drvdata(pdev, vuart);