[src/trunk]: src/sys/dev/ic Various improvements for connecting HD44780s usin...

[joff <joff%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/7f851cb39092
branches:  trunk
changeset: 572583:7f851cb39092
user:      joff <joff%NetBSD.org@localhost>
date:      Sat Jan 08 20:17:22 2005 +0000

description:
Various improvements for connecting HD44780s using bit-banging style devices

o add sc_writereg and sc_readreg functions that get passed the hd44780_chip
  struct and RS (register-select) signal
o add sc_dev to struct hd44780_chip so upper level read/write routines can get
  back to their parent softc
o change TIMEOUT_XXX to HD_TIMEOUT_XXX
o remove sc_rread and sc_rwrite in favor of new sc_writereg and sc_readreg
o add new flag HD_UP to sc_flags that is set once 4bit/8bit mode selection
  has been finalized.
o remove sc_irwrite, MD readreg/writereg should check state of HD_UP instead

diffstat:

 sys/dev/ic/hd44780_subr.c |  132 ++++++++++++++++++++++++---------------------
 sys/dev/ic/hd44780_subr.h |   32 +++-------
 2 files changed, 80 insertions(+), 84 deletions(-)

diffs (287 lines):

diff -r 21ad2abbe1d7 -r 7f851cb39092 sys/dev/ic/hd44780_subr.c
--- a/sys/dev/ic/hd44780_subr.c Sat Jan 08 18:48:56 2005 +0000
+++ b/sys/dev/ic/hd44780_subr.c Sat Jan 08 20:17:22 2005 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: hd44780_subr.c,v 1.1 2003/01/20 01:20:50 soren Exp $ */
+/* $NetBSD: hd44780_subr.c,v 1.2 2005/01/08 20:17:22 joff Exp $ */
 
 /*
  * Copyright (c) 2002 Dennis I. Chernoivanov
@@ -32,7 +32,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: hd44780_subr.c,v 1.1 2003/01/20 01:20:50 soren Exp $");
+__KERNEL_RCSID(0, "$NetBSD: hd44780_subr.c,v 1.2 2005/01/08 20:17:22 joff Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -59,7 +59,7 @@
        struct hd44780_chip *sc;
 {
        /* Putc/getc are supposed to be set by platform-dependent code. */
-       if ((sc->sc_rwrite == NULL) || (sc->sc_rread == NULL))
+       if ((sc->sc_writereg == NULL) || (sc->sc_readreg == NULL))
                sc->sc_dev_ok = 0;
 
        /* Make sure that HD_MAX_CHARS is enough. */
@@ -69,7 +69,8 @@
                sc->sc_dev_ok = 0;
 
        if (sc->sc_dev_ok) {
-               hd44780_init(sc);
+               if ((sc->sc_flags & HD_UP) == 0)
+                       hd44780_init(sc);
 
                /* Turn display on and clear it. */
                hd44780_ir_write(sc, cmd_dispctl(1, 0, 0));
@@ -86,20 +87,11 @@
 {
        u_int8_t cmd;
 
-       bus_space_tag_t iot;
-       bus_space_handle_t ioh;
-
-       iot = sc->sc_iot;
-       ioh = sc->sc_ioir;
-
-       if (sc->sc_irwrite == NULL)
-               sc->sc_irwrite = sc->sc_rwrite;
-
        cmd = cmd_init(sc->sc_flags & HD_8BIT);
-       sc->sc_irwrite(iot, ioh, cmd);
-       delay(TIMEOUT_LONG);
-       sc->sc_irwrite(iot, ioh, cmd);
-       sc->sc_irwrite(iot, ioh, cmd);
+       hd44780_ir_write(sc, cmd);
+       delay(HD_TIMEOUT_LONG);
+       hd44780_ir_write(sc, cmd);
+       hd44780_ir_write(sc, cmd);
 
        cmd = cmd_funcset(
                        sc->sc_flags & HD_8BIT,
@@ -107,16 +99,14 @@
                        sc->sc_flags & HD_BIGFONT);
 
        if ((sc->sc_flags & HD_8BIT) == 0)
-               sc->sc_irwrite(iot, ioh, cmd);
+               hd44780_ir_write(sc, cmd);
+
+       sc->sc_flags |= HD_UP;
 
-       /* Interface is set to the proper width, use normal 'write' op. */
-       sc->sc_rwrite(iot, ioh, cmd);
-       cmd = cmd_dispctl(0, 0, 0);
-       sc->sc_rwrite(iot, ioh, cmd);
-       cmd = cmd_clear();
-       sc->sc_rwrite(iot, ioh, cmd);
-       cmd = cmd_modset(1, 0);
-       sc->sc_rwrite(iot, ioh, cmd);
+       hd44780_ir_write(sc, cmd);
+       hd44780_ir_write(sc, cmd_dispctl(0, 0, 0));
+       hd44780_ir_write(sc, cmd_clear());
+       hd44780_ir_write(sc, cmd_modset(1, 0));
 }
 
 /*
@@ -320,70 +310,86 @@
 
 #if defined(HD44780_STD_WIDE)
 /*
- * Standard 8-bit version of 'sc_rwrite' (8-bit port, 8-bit access)
+ * Standard 8-bit version of 'sc_writereg' (8-bit port, 8-bit access)
  */
 void
-hd44780_rwrite(iot, ioh, cmd)
-       bus_space_tag_t iot;
-       bus_space_handle_t ioh;
+hd44780_writereg(sc, reg, cmd)
+       struct hd44780_chip *sc;
+       u_int32_t reg;
        u_int8_t cmd;
 {
+       bus_space_tag_t iot = sc->sc_iot;
+       bus_space_handle_t ioh;
+
+       if (reg == 0)
+               ioh = sc->sc_ioir; 
+       else
+               ioh = sc->sc_iodr;
+
        bus_space_write_1(iot, ioh, 0x00, cmd);
-       delay(TIMEOUT_NORMAL);
+       delay(HD_TIMEOUT_NORMAL);
 }
 
 /*
- * Standard 8-bit version of 'sc_rread' (8-bit port, 8-bit access)
+ * Standard 8-bit version of 'sc_readreg' (8-bit port, 8-bit access)
  */
 u_int8_t
-hd44780_rread(iot, ioh)
-       bus_space_tag_t iot;
+hd44780_readreg(sc, reg)
+       struct hd44780_chip *sc;
+       u_int32_t reg;
+{
+       bus_space_tag_t iot = sc->sc_iot;
        bus_space_handle_t ioh;
-{
-       delay(TIMEOUT_NORMAL);
+
+       if (reg == 0)
+               ioh = sc->sc_ioir; 
+       else
+               ioh = sc->sc_iodr;
+
+       delay(HD_TIMEOUT_NORMAL);
        return bus_space_read_1(iot, ioh, 0x00);
 }
 #elif defined(HD44780_STD_SHORT)
 /*
- * Standard 4-bit version of 'sc_irwrite' (4-bit port, 8-bit access)
+ * Standard 4-bit version of 'sc_writereg' (4-bit port, 8-bit access)
  */
 void
-hd44780_irwrite(iot, ioh, cmd)
-       bus_space_tag_t iot;
-       bus_space_handle_t ioh;
+hd44780_writereg(sc, reg, cmd)
+       struct hd44780_chip *sc;
+       u_int32_t reg;
        u_int8_t cmd;
 {
-       /* first four instructions emitted in 8-bit mode */
+       bus_space_tag_t iot = sc->sc_iot;
+       bus_space_handle_t ioh;
+
+       if (reg == 0)
+               ioh = sc->sc_ioir; 
+       else
+               ioh = sc->sc_iodr;
+
        bus_space_write_1(iot, ioh, 0x00, hi_bits(cmd));
-       delay(TIMEOUT_NORMAL);
+       if (sc->sc_flags & HD_UP) 
+               bus_space_write_1(iot, ioh, 0x00, lo_bits(cmd));
+       delay(HD_TIMEOUT_NORMAL);
 }
 
 /*
- * Standard 4-bit version of 'sc_rrwrite' (4-bit port, 8-bit access)
- */
-void
-hd44780_rwrite(iot, ioh, cmd)
-       bus_space_tag_t iot;
-       bus_space_handle_t ioh;
-       u_int8_t cmd;
-{
-       bus_space_write_1(iot, ioh, 0x00, hi_bits(cmd));
-       bus_space_write_1(iot, ioh, 0x00, lo_bits(cmd));
-       delay(TIMEOUT_NORMAL);
-}
-
-/*
- * Standard 4-bit version of 'sc_rread' (4-bit port, 8-bit access)
+ * Standard 4-bit version of 'sc_readreg' (4-bit port, 8-bit access)
  */
 u_int8_t
-hd44780_rread(iot, ioh)
-       bus_space_tag_t iot;
-       bus_space_handle_t ioh;
+hd44780_readreg(sc, reg)
+       struct hd44780_chip *sc;
+       u_int32_t reg;
 {
-       u_int8_t rd;
-       u_int8_t dat;
+       bus_space_tag_t iot = sc->sc_iot;
+       bus_space_handle_t ioh;
+       u_int8_t rd, dat;
 
-       delay(TIMEOUT_NORMAL);
+       if (reg == 0)
+               ioh = sc->sc_ioir; 
+       else
+               ioh = sc->sc_iodr;
+
        rd = bus_space_read_1(iot, ioh, 0x00);
        dat = (rd & 0x0f) << 4;
        rd = bus_space_read_1(iot, ioh, 0x00);
diff -r 21ad2abbe1d7 -r 7f851cb39092 sys/dev/ic/hd44780_subr.h
--- a/sys/dev/ic/hd44780_subr.h Sat Jan 08 18:48:56 2005 +0000
+++ b/sys/dev/ic/hd44780_subr.h Sat Jan 08 20:17:22 2005 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: hd44780_subr.h,v 1.1 2003/01/20 01:20:51 soren Exp $ */
+/* $NetBSD: hd44780_subr.h,v 1.2 2005/01/08 20:17:22 joff Exp $ */
 
 /*
  * Copyright (c) 2002 Dennis I. Chernoivanov
@@ -80,6 +80,7 @@
 #define HD_MULTILINE           0x02    /* 2 lines if set, 1 otherwise */
 #define HD_BIGFONT             0x04    /* 5x10 if set, 5x8 otherwise */
 #define HD_KEYPAD              0x08    /* if set, keypad is connected */
+#define HD_UP                  0x10    /* if set, lcd has been initialized */
        u_char sc_flags;
 
        u_char sc_rows;                 /* visible rows */
@@ -91,18 +92,11 @@
        bus_space_handle_t sc_ioir;     /* instruction register */
        bus_space_handle_t sc_iodr;     /* data register */
 
-       /*
-        * This one is here to make initialization generic. If 4-bit
-        * connection is used, the device still starts as if it was
-        * 8-bit connected, so a special care is needed for such case.
-        * If set to NULL, normal 'sc_rwrite()' function will be used
-        * during initialization.
-        */
-       void     (* sc_irwrite)(bus_space_tag_t, bus_space_handle_t, u_int8_t);
+       struct device *sc_dev;          /* Pointer to parent device */
 
        /* Generic write/read byte entries. */
-       void     (* sc_rwrite)(bus_space_tag_t, bus_space_handle_t, u_int8_t);
-       u_int8_t (* sc_rread)(bus_space_tag_t, bus_space_handle_t);
+       void     (* sc_writereg)(struct hd44780_chip *, u_int32_t, u_int8_t);
+       u_int8_t (* sc_readreg)(struct hd44780_chip *, u_int32_t);
 };
 
 #define hd44780_busy_wait(sc) \
@@ -111,17 +105,17 @@
 #define hd44780_ir_write(sc, dat) \
        do {                                                            \
                hd44780_busy_wait(sc);                                  \
-               (sc)->sc_rwrite((sc)->sc_iot, (sc)->sc_ioir, (dat));    \
+               (sc)->sc_writereg((sc), 0, (dat));                      \
        } while(0)
 
 #define hd44780_ir_read(sc) \
-       (sc)->sc_rread((sc)->sc_iot, (sc)->sc_ioir)
+       (sc)->sc_readreg((sc), 0)
 
 #define hd44780_dr_write(sc, dat) \
-       (sc)->sc_rwrite((sc)->sc_iot, (sc)->sc_iodr, (dat))
+       (sc)->sc_writereg((sc), 1, (dat))
 
 #define hd44780_dr_read(sc) \
-       (sc)->sc_rread((sc)->sc_iot, (sc)->sc_iodr)
+       (sc)->sc_readreg((sc), 1)
 
 void hd44780_attach_subr(struct hd44780_chip *);
 int  hd44780_ioctl_subr(struct hd44780_chip *, u_long, caddr_t);
@@ -131,13 +125,9 @@
 #define HD_DDRAM_WRITE 0x1
 int  hd44780_ddram_io(struct hd44780_chip *, struct hd44780_io *, u_char);
 
-#if defined(HD44780_STD_SHORT)
-void     hd44780_irwrite(bus_space_tag_t, bus_space_handle_t, u_int8_t);
-#endif
-
 #if defined(HD44780_STD_WIDE) || defined(HD44780_STD_SHORT)
-void     hd44780_rwrite(bus_space_tag_t, bus_space_handle_t, u_int8_t);
-u_int8_t hd44780_rread(bus_space_tag_t, bus_space_handle_t);
+void     hd44780_writereg(struct hd44780_chip *, u_int32_t, u_int8_t);
+u_int8_t hd44780_readreg(struct hd44780_chip *, u_int32_t);
 #endif
 
 #endif /* _KERNEL */