[PATCH v3 6/7] hw/misc/mps2-scc: Use the LED device

[Philippe Mathieu-Daudé]

Per the 'ARM MPS2 and MPS2+ FPGA Prototyping Boards Technical
Reference Manual' (100112_0200_07_en):

  2.1  Overview of the MPS2 and MPS2+ hardware

       The MPS2 and MPS2+ FPGA Prototyping Boards contain the
       following components and interfaces:

       * User switches and user LEDs:

         - Two green LEDs and two push buttons that connect to
           the FPGA.
         - Eight green LEDs and one 8-way dip switch that connect
           to the MCC.

Add the 8 LEDs connected to the MCC.

This remplaces the 'mps2_scc_leds' trace events by the generic
'led_set_intensity' event.

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
https://youtu.be/l9kD70uPchk?t=288
---
 include/hw/misc/mps2-scc.h |  1 +
 hw/misc/mps2-scc.c         | 23 ++++++++++++-----------
 hw/misc/Kconfig            |  1 +
 hw/misc/trace-events       |  1 -
 4 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/include/hw/misc/mps2-scc.h b/include/hw/misc/mps2-scc.h
index 7045473788..29e12b832b 100644
--- a/include/hw/misc/mps2-scc.h
+++ b/include/hw/misc/mps2-scc.h
@@ -25,6 +25,7 @@ typedef struct {
 
     /*< public >*/
     MemoryRegion iomem;
+    DeviceState *led[8];
 
     uint32_t cfg0;
     uint32_t cfg1;
diff --git a/hw/misc/mps2-scc.c b/hw/misc/mps2-scc.c
index 9d0909e7b3..2e59a382ec 100644
--- a/hw/misc/mps2-scc.c
+++ b/hw/misc/mps2-scc.c
@@ -20,11 +20,13 @@
 #include "qemu/osdep.h"
 #include "qemu/log.h"
 #include "qemu/module.h"
+#include "qemu/bitops.h"
 #include "trace.h"
 #include "hw/sysbus.h"
 #include "migration/vmstate.h"
 #include "hw/registerfields.h"
 #include "hw/misc/mps2-scc.h"
+#include "hw/misc/led.h"
 #include "hw/qdev-properties.h"
 
 REG32(CFG0, 0)
@@ -152,18 +154,10 @@ static void mps2_scc_write(void *opaque, hwaddr offset, 
uint64_t value,
         s->cfg0 = value;
         break;
     case A_CFG1:
-        /* CFG1 bits [7:0] control the board LEDs. We don't currently have
-         * a mechanism for displaying this graphically, so use a trace event.
-         */
-        trace_mps2_scc_leds(value & 0x80 ? '*' : '.',
-                            value & 0x40 ? '*' : '.',
-                            value & 0x20 ? '*' : '.',
-                            value & 0x10 ? '*' : '.',
-                            value & 0x08 ? '*' : '.',
-                            value & 0x04 ? '*' : '.',
-                            value & 0x02 ? '*' : '.',
-                            value & 0x01 ? '*' : '.');
         s->cfg1 = value;
+        for (size_t i = 0; i < ARRAY_SIZE(s->led); i++) {
+            led_set_state(LED(s->led[i]), !!extract32(value, i, 1));
+        }
         break;
     case A_CFGDATA_OUT:
         s->cfgdata_out = value;
@@ -245,6 +239,13 @@ static void mps2_scc_init(Object *obj)
 
     memory_region_init_io(&s->iomem, obj, &mps2_scc_ops, s, "mps2-scc", 
0x1000);
     sysbus_init_mmio(sbd, &s->iomem);
+
+    for (size_t i = 0; i < ARRAY_SIZE(s->led); i++) {
+        char *name = g_strdup_printf("SCC LED%zu", i);
+        s->led[i] = create_led(obj, LED_COLOR_GREEN,
+                               name, LED_RESET_INTENSITY_ACTIVE_HIGH);
+        g_free(name);
+    }
 }
 
 static void mps2_scc_realize(DeviceState *dev, Error **errp)
diff --git a/hw/misc/Kconfig b/hw/misc/Kconfig
index 889757731b..f278f7f354 100644
--- a/hw/misc/Kconfig
+++ b/hw/misc/Kconfig
@@ -97,6 +97,7 @@ config MPS2_FPGAIO
 
 config MPS2_SCC
     bool
+    select LED
 
 config TZ_MPC
     bool
diff --git a/hw/misc/trace-events b/hw/misc/trace-events
index 8bc7a675e8..490a0f341a 100644
--- a/hw/misc/trace-events
+++ b/hw/misc/trace-events
@@ -81,7 +81,6 @@ aspeed_scu_write(uint64_t offset, unsigned size, uint32_t 
data) "To 0x%" PRIx64
 mps2_scc_read(uint64_t offset, uint64_t data, unsigned size) "MPS2 SCC read: 
offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u"
 mps2_scc_write(uint64_t offset, uint64_t data, unsigned size) "MPS2 SCC write: 
offset 0x%" PRIx64 " data 0x%" PRIx64 " size %u"
 mps2_scc_reset(void) "MPS2 SCC: reset"
-mps2_scc_leds(char led7, char led6, char led5, char led4, char led3, char 
led2, char led1, char led0) "MPS2 SCC LEDs: %c%c%c%c%c%c%c%c"
 mps2_scc_cfg_write(unsigned function, unsigned device, uint32_t value) "MPS2 
SCC config write: function %d device %d data 0x%" PRIx32
 mps2_scc_cfg_read(unsigned function, unsigned device, uint32_t value) "MPS2 
SCC config read: function %d device %d data 0x%" PRIx32
 
-- 
2.21.3