Merge tag 'tty-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty / serial updates from Greg KH:
 "Here is the big set of tty/serial driver changes for 6.10-rc1.
  Included in here are:

   - Usual good set of api cleanups and evolution by Jiri Slaby to make
     the serial interfaces move out of the 1990's by using kfifos
     instead of hand-rolling their own logic.

   - 8250_exar driver updates

   - max3100 driver updates

   - sc16is7xx driver updates

   - exar driver updates

   - sh-sci driver updates

   - tty ldisc api addition to help refuse bindings

   - other smaller serial driver updates

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

* tag 'tty-6.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (113 commits)
  serial: Clear UPF_DEAD before calling tty_port_register_device_attr_serdev()
  serial: imx: Raise TX trigger level to 8
  serial: 8250_pnp: Simplify "line" related code
  serial: sh-sci: simplify locking when re-issuing RXDMA fails
  serial: sh-sci: let timeout timer only run when DMA is scheduled
  serial: sh-sci: describe locking requirements for invalidating RXDMA
  serial: sh-sci: protect invalidating RXDMA on shutdown
  tty: add the option to have a tty reject a new ldisc
  serial: core: Call device_set_awake_path() for console port
  dt-bindings: serial: brcm,bcm2835-aux-uart: convert to dtschema
  tty: serial: uartps: Add support for uartps controller reset
  arm64: zynqmp: Add resets property for UART nodes
  dt-bindings: serial: cdns,uart: Add optional reset property
  serial: 8250_pnp: Switch to DEFINE_SIMPLE_DEV_PM_OPS()
  serial: 8250_exar: Keep the includes sorted
  serial: 8250_exar: Make type of bit the same in exar_ee_*_bit()
  serial: 8250_exar: Use BIT() in exar_ee_read()
  serial: 8250_exar: Switch to use dev_err_probe()
  serial: 8250_exar: Return directly from switch-cases
  serial: 8250_exar: Decrease indentation level
  ...

1 files changed, 17 insertions, 22 deletions

diff --git a/drivers/tty/serial/max310x.c b/drivers/tty/serial/max310x.c
index 14dd9cfaa9f7..35369a2f77b2 100644
--- a/drivers/tty/serial/max310x.c
+++ b/drivers/tty/serial/max310x.c
@@ -747,8 +747,9 @@ static void max310x_handle_rx(struct uart_port *port, unsigned int rxlen)
 
 static void max310x_handle_tx(struct uart_port *port)
 {
-	struct circ_buf *xmit = &port->state->xmit;
-	unsigned int txlen, to_send, until_end;
+	struct tty_port *tport = &port->state->port;
+	unsigned int txlen, to_send;
+	unsigned char *tail;
 
 	if (unlikely(port->x_char)) {
 		max310x_port_write(port, MAX310X_THR_REG, port->x_char);
@@ -757,32 +758,26 @@ static void max310x_handle_tx(struct uart_port *port)
 		return;
 	}
 
-	if (uart_circ_empty(xmit) || uart_tx_stopped(port))
+	if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port))
 		return;
 
-	/* Get length of data pending in circular buffer */
-	to_send = uart_circ_chars_pending(xmit);
-	until_end = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
-	if (likely(to_send)) {
+	/*
+	 * It's a circ buffer -- wrap around.
+	 * We could do that in one SPI transaction, but meh.
+	 */
+	while (!kfifo_is_empty(&tport->xmit_fifo)) {
 		/* Limit to space available in TX FIFO */
 		txlen = max310x_port_read(port, MAX310X_TXFIFOLVL_REG);
 		txlen = port->fifosize - txlen;
-		to_send = (to_send > txlen) ? txlen : to_send;
-
-		if (until_end < to_send) {
-			/*
-			 * It's a circ buffer -- wrap around.
-			 * We could do that in one SPI transaction, but meh.
-			 */
-			max310x_batch_write(port, xmit->buf + xmit->tail, until_end);
-			max310x_batch_write(port, xmit->buf, to_send - until_end);
-		} else {
-			max310x_batch_write(port, xmit->buf + xmit->tail, to_send);
-		}
+		if (!txlen)
+			break;
+
+		to_send = kfifo_out_linear_ptr(&tport->xmit_fifo, &tail, txlen);
+		max310x_batch_write(port, tail, to_send);
 		uart_xmit_advance(port, to_send);
 	}
 
-	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
+	if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
 		uart_write_wakeup(port);
 }
 
@@ -1478,7 +1473,7 @@ static struct regmap_config regcfg = {
 	.reg_bits = 8,
 	.val_bits = 8,
 	.write_flag_mask = MAX310X_WRITE_BIT,
-	.cache_type = REGCACHE_RBTREE,
+	.cache_type = REGCACHE_MAPLE,
 	.max_register = MAX310X_REG_1F,
 	.writeable_reg = max310x_reg_writeable,
 	.volatile_reg = max310x_reg_volatile,
@@ -1582,7 +1577,7 @@ static int max310x_i2c_extended_reg_enable(struct device *dev, bool enable)
 static struct regmap_config regcfg_i2c = {
 	.reg_bits = 8,
 	.val_bits = 8,
-	.cache_type = REGCACHE_RBTREE,
+	.cache_type = REGCACHE_MAPLE,
 	.writeable_reg = max310x_reg_writeable,
 	.volatile_reg = max310x_reg_volatile,
 	.precious_reg = max310x_reg_precious,