Merge tag 'tty-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty

Pull tty/serial driver updates from Greg KH:
 "Here is the big tty and serial driver update for 4.8-rc1.

  Lots of good cleanups from Jiri on a number of vt and other tty
  related things, and the normal driver updates.  Full details are in
  the shortlog.

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

* tag 'tty-4.8-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (90 commits)
  tty/serial: atmel: enforce tasklet init and termination sequences
  serial: sh-sci: Stop transfers in sci_shutdown()
  serial: 8250_ingenic: drop #if conditional surrounding earlycon code
  serial: 8250_mtk: drop !defined(MODULE) conditional
  serial: 8250_uniphier: drop !defined(MODULE) conditional
  earlycon: mark earlycon code as __used iif the caller is built-in
  tty/serial/8250: use mctrl_gpio helpers
  serial: mctrl_gpio: enable API usage only for initialized mctrl_gpios struct
  serial: mctrl_gpio: add modem control read routine
  tty/serial/8250: make UART_MCR register access consistent
  serial: 8250_mid: Read RX buffer on RX DMA timeout for DNV
  serial: 8250_dma: Export serial8250_rx_dma_flush()
  dmaengine: hsu: Export hsu_dma_get_status()
  tty: serial: 8250: add CON_CONSDEV to flags
  tty: serial: samsung: add byte-order aware bit functions
  tty: serial: samsung: fixup accessors for endian
  serial: sirf: make fifo functions static
  serial: mps2-uart: make driver explicitly non-modular
  serial: mvebu-uart: free the IRQ in ->shutdown()
  serial/bcm63xx_uart: use correct alias naming
  ...

1 files changed, 36 insertions, 2 deletions

diff --git a/include/linux/console_struct.h b/include/linux/console_struct.h
index e329ee2667e1..6fd3c908a340 100644
--- a/include/linux/console_struct.h
+++ b/include/linux/console_struct.h
@@ -21,6 +21,38 @@ struct uni_pagedir;
 
 #define NPAR 16
 
+/*
+ * Example: vc_data of a console that was scrolled 3 lines down.
+ *
+ *                              Console buffer
+ * vc_screenbuf ---------> +----------------------+-.
+ *                         | initializing W       |  \
+ *                         | initializing X       |   |
+ *                         | initializing Y       |    > scroll-back area
+ *                         | initializing Z       |   |
+ *                         |                      |  /
+ * vc_visible_origin ---> ^+----------------------+-:
+ * (changes by scroll)    || Welcome to linux     |  \
+ *                        ||                      |   |
+ *           vc_rows --->< | login: root          |   |  visible on console
+ *                        || password:            |    > (vc_screenbuf_size is
+ * vc_origin -----------> ||                      |   |   vc_size_row * vc_rows)
+ * (start when no scroll) || Last login: 12:28    |  /
+ *                        v+----------------------+-:
+ *                         | Have a lot of fun... |  \
+ * vc_pos -----------------|--------v             |   > scroll-front area
+ *                         | ~ # cat_             |  /
+ * vc_scr_end -----------> +----------------------+-:
+ * (vc_origin +            |                      |  \ EMPTY, to be filled by
+ *  vc_screenbuf_size)     |                      |  / vc_video_erase_char
+ *                         +----------------------+-'
+ *                         <---- 2 * vc_cols ----->
+ *                         <---- vc_size_row ----->
+ *
+ * Note that every character in the console buffer is accompanied with an
+ * attribute in the buffer right after the character. This is not depicted
+ * in the figure.
+ */
 struct vc_data {
 	struct tty_port port;			/* Upper level data */
 
@@ -74,7 +106,6 @@ struct vc_data {
 	unsigned int	vc_decawm	: 1;	/* Autowrap Mode */
 	unsigned int	vc_deccm	: 1;	/* Cursor Visible */
 	unsigned int	vc_decim	: 1;	/* Insert Mode */
-	unsigned int	vc_deccolm	: 1;	/* 80/132 Column Mode */
 	/* attribute flags */
 	unsigned int	vc_intensity	: 2;	/* 0=half-bright, 1=normal, 2=bold */
 	unsigned int    vc_italic:1;
@@ -136,6 +167,9 @@ extern void vc_SAK(struct work_struct *work);
 
 #define CUR_DEFAULT CUR_UNDERLINE
 
-#define CON_IS_VISIBLE(conp) (*conp->vc_display_fg == conp)
+static inline bool con_is_visible(const struct vc_data *vc)
+{
+	return *vc->vc_display_fg == vc;
+}
 
 #endif /* _LINUX_CONSOLE_STRUCT_H */