[src/trunk]: src/sys/dev/spi ssdfb: support the 4-wire SPI interface

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

details:   https://anonhg.NetBSD.org/src/rev/34bfcff8e07a
branches:  trunk
changeset: 1022673:34bfcff8e07a
user:      tnn <tnn%NetBSD.org@localhost>
date:      Sun Aug 01 14:56:18 2021 +0000

description:
ssdfb: support the 4-wire SPI interface

diffstat:

 sys/dev/spi/ssdfb_spi.c |  44 ++++++++++++++++++++++++++++++++++----------
 1 files changed, 34 insertions(+), 10 deletions(-)

diffs (110 lines):

diff -r 24cc05f6a8da -r 34bfcff8e07a sys/dev/spi/ssdfb_spi.c
--- a/sys/dev/spi/ssdfb_spi.c   Sun Aug 01 14:51:41 2021 +0000
+++ b/sys/dev/spi/ssdfb_spi.c   Sun Aug 01 14:56:18 2021 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: ssdfb_spi.c,v 1.5 2021/01/27 02:32:31 thorpej Exp $ */
+/* $NetBSD: ssdfb_spi.c,v 1.6 2021/08/01 14:56:18 tnn Exp $ */
 
 /*
  * Copyright (c) 2019 The NetBSD Foundation, Inc.
@@ -30,7 +30,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ssdfb_spi.c,v 1.5 2021/01/27 02:32:31 thorpej Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ssdfb_spi.c,v 1.6 2021/08/01 14:56:18 tnn Exp $");
 
 #include <sys/param.h>
 #include <sys/device.h>
@@ -39,6 +39,10 @@
 #include <dev/rasops/rasops.h>
 #include <dev/spi/spivar.h>
 #include <dev/ic/ssdfbvar.h>
+#include "opt_fdt.h"
+#ifdef FDT
+#include <dev/fdt/fdtvar.h>
+#endif
 
 struct bs_state {
        uint8_t *base;
@@ -49,6 +53,9 @@
 struct ssdfb_spi_softc {
        struct ssdfb_softc      sc;
        struct spi_handle       *sc_sh;
+#ifdef FDT
+       struct fdtbus_gpio_pin  *sc_gpio_dc;
+#endif
        bool                    sc_3wiremode;
 };
 
@@ -74,7 +81,8 @@
     ssdfb_spi_match, ssdfb_spi_attach, NULL, NULL);
 
 static const struct device_compatible_entry compat_data[] = {
-       { .compat = "solomon,ssd1322" },
+       { .compat = "solomon,ssd1306",  .value = SSDFB_PRODUCT_SSD1306_GENERIC },
+       { .compat = "solomon,ssd1322",  .value = SSDFB_PRODUCT_SSD1322_GENERIC },
        DEVICE_COMPAT_EOL
 };
 
@@ -108,8 +116,14 @@
        sc->sc.sc_dev = self;
        sc->sc_sh = sa->sa_handle;
        sc->sc.sc_cookie = (void *)sc;
-       if ((flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) == SSDFB_PRODUCT_UNKNOWN)
-               flags |= SSDFB_PRODUCT_SSD1322_GENERIC;
+       if ((flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) == SSDFB_PRODUCT_UNKNOWN) {
+               const struct device_compatible_entry *dce =
+                       device_compatible_lookup(sa->sa_compat, sa->sa_ncompat, compat_data);
+               if (dce)
+                       flags |= (int)dce->value;
+               else
+                       flags |= SSDFB_PRODUCT_SSD1322_GENERIC;
+       }
        /*
         * Note on interface modes.
         *
@@ -117,11 +131,18 @@
         * the bit that determines if the lower 8 bits are command or data.
         *
         * 4 wire mode sends 8 bit sequences and requires an auxiliary GPIO
-        * pin for the command/data bit. But in other to allocate a GPIO pin
-        * we need to use fdt, so only support 3 wire mode in this frontend,
-        * at least for now.
+        * pin for the command/data bit.
         */
        sc->sc_3wiremode = true;
+#ifdef FDT
+       const int phandle = sa->sa_cookie;
+       sc->sc_gpio_dc = fdtbus_gpio_acquire(phandle, "dc-gpio", GPIO_PIN_OUTPUT);
+       if (!sc->sc_gpio_dc)
+               sc->sc_gpio_dc = fdtbus_gpio_acquire(phandle, "cd-gpio", GPIO_PIN_OUTPUT);
+       sc->sc_3wiremode = (sc->sc_gpio_dc == NULL);
+#else
+       sc->sc_3wiremode = true;
+#endif
 
        switch (flags & SSDFB_ATTACH_FLAG_PRODUCT_MASK) {
        case SSDFB_PRODUCT_SSD1322_GENERIC:
@@ -141,7 +162,7 @@
        } else {
                sc->sc.sc_cmd = ssdfb_spi_cmd_4wire;
        }
-       
+
        ssdfb_attach(&sc->sc, flags);
 
        device_printf(sc->sc.sc_dev, "%d-wire SPI interface\n",
@@ -264,8 +285,11 @@
 static void
 ssdfb_spi_4wire_set_dc(struct ssdfb_spi_softc *sc, int value)
 {
-       /* TODO: this should toggle an auxilliary GPIO pin */
+#ifdef FDT
+       fdtbus_gpio_write_raw(sc->sc_gpio_dc, value);
+#else
        panic("ssdfb_spi_4wire_set_dc");
+#endif
 }
 
 static int