[Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Filip Navara]

This patch introduces an emulation of the rotary encoder that could be connected
to GPIO controller.

An internal state is maintained with the values of the output pins. When a key is
pressed the state is modified accordingly and the information is signaled on the
output pins.

Key mappings are specified by the "key-left" and "key-left-alt" properties for a
counter-clockwise direction and "key-right" and "key-right-alt" for a clockwise
direction.

Signed-off-by: Filip Navara <filip.navara@gmail.com>
---
 Makefile.target  |    1 +
 hw/gpio_rotary.c |  136 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 137 insertions(+), 0 deletions(-)
 create mode 100644 hw/gpio_rotary.c

diff --git a/Makefile.target b/Makefile.target
index 1a71f3a..0e66139 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -666,6 +666,7 @@ obj-y += framebuffer.o
 obj-y += syborg.o syborg_fb.o syborg_interrupt.o syborg_keyboard.o
 obj-y += syborg_serial.o syborg_timer.o syborg_pointer.o syborg_rtc.o
 obj-y += syborg_virtio.o
+obj-y += gpio_rotary.o
 CPPFLAGS += -DHAS_AUDIO
 endif
 ifeq ($(TARGET_BASE_ARCH), sh4)
diff --git a/hw/gpio_rotary.c b/hw/gpio_rotary.c
new file mode 100644
index 0000000..c35810c
--- /dev/null
+++ b/hw/gpio_rotary.c
@@ -0,0 +1,136 @@
+/*
+ * GPIO Rotary Coder
+ *
+ * Copyright (c) 2009 Filip Navara
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "sysbus.h"
+#include "console.h"
+
+typedef struct RotaryCoderState {
+    SysBusDevice busdev;
+    qemu_irq out[2];
+    uint8_t state;
+    uint8_t key_left;
+    uint8_t key_right;
+    uint8_t key_left_alt;
+    uint8_t key_right_alt;
+    uint8_t extension;
+} RotaryCoderState;
+
+static void rotary_update(RotaryCoderState *s, int direction)
+{
+    s->state += direction;
+    s->state %= 4;    
+
+    qemu_set_irq(s->out[0], s->state == 1 || s->state == 2);
+    qemu_set_irq(s->out[1], s->state == 2 || s->state == 3);
+}
+
+static void rotary_keyboard_event(void *opaque, int keycode)
+{
+    RotaryCoderState *s = opaque;
+
+    if (keycode == 0xe0 && !s->extension) {
+        s->extension = 0x80;
+        return;
+    }
+
+    if (!(keycode & 0x80)) {   
+        keycode &= 0x7f;
+        keycode |= s->extension;
+
+        if (keycode == s->key_left || keycode == s->key_left_alt) {
+            rotary_update(s, 3);
+        } else if (keycode == s->key_right || keycode == s->key_right_alt) {
+            rotary_update(s, 1);
+        }
+    }
+
+    s->extension = 0;
+}
+
+static void rotary_save(QEMUFile *f, void *opaque)
+{
+    RotaryCoderState *s = opaque;
+
+    qemu_put_byte(f, s->state);
+    qemu_put_byte(f, s->extension);
+}
+
+static int rotary_load(QEMUFile *f, void *opaque, int version_id)
+{
+    RotaryCoderState *s = opaque;
+
+    if (version_id != 1)
+        return -EINVAL;
+
+    s->state = qemu_get_byte(f);
+    s->extension = qemu_get_byte(f);
+
+    return 0;
+}
+
+/*
+static void rotary_late_init(DeviceState *dev)
+{
+    RotaryCoderState *s = FROM_SYSBUS(RotaryCoderState, sysbus_from_qdev(dev));
+
+    rotary_update(s);
+}
+*/
+
+static void rotary_init(SysBusDevice *dev)
+{
+    RotaryCoderState *s = FROM_SYSBUS(RotaryCoderState, dev);
+
+    s->key_left = qdev_get_prop_int(&dev->qdev, "key-left", 0xcb);
+    s->key_right = qdev_get_prop_int(&dev->qdev, "key-right", 0xcd);
+    s->key_left_alt = qdev_get_prop_int(&dev->qdev, "key-left-alt", 0x4b);
+    s->key_right_alt = qdev_get_prop_int(&dev->qdev, "key-right-alt", 0x4d);
+
+    qdev_init_gpio_out(&dev->qdev, s->out, 2);
+
+    qemu_add_kbd_event_handler(rotary_keyboard_event, s);
+
+    register_savevm("gpio_rotary", -1, 1, rotary_save, rotary_load, s);
+}
+
+static SysBusDeviceInfo rotary_info = {
+    .init = rotary_init,
+    /* .qdev.late_init = rotary_late_init, */
+    .qdev.name  = "gpio,rotary",
+    .qdev.size  = sizeof(RotaryCoderState),
+    .qdev.props = (DevicePropList[]) {
+        {.name = "key-left", .type = PROP_TYPE_INT},
+        {.name = "key-right", .type = PROP_TYPE_INT},
+        {.name = "key-left-alt", .type = PROP_TYPE_INT},
+        {.name = "key-right-alt", .type = PROP_TYPE_INT},
+        {.name = NULL}
+    }
+};
+
+static void rotary_register(void)
+{
+    sysbus_register_withprop(&rotary_info);
+}
+
+device_init(rotary_register)
-- 
1.6.3.msysgit.0

Re: [Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Blue Swirl]

On Wed, 15 Jul 09 16:52:12 Central Europe Standard Time, Filip Navara
<filip.navara@gmail.com> wrote:
> This patch introduces an emulation of the rotary encoder that could be connected
>  to GPIO controller.

How about reset handling (qemu_register_reset)?

Re: [Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Filip Navara]

On Wed, Jul 15, 2009 at 5:33 PM, Blue Swirl<blauwirbel@gmail.com> wrote:
> On Wed, 15 Jul 09 16:52:12 Central Europe Standard Time, Filip Navara
> <filip.navara@gmail.com> wrote:
>> This patch introduces an emulation of the rotary encoder that could be connected
>>  to GPIO controller.
>
> How about reset handling (qemu_register_reset)?
>

Good point, it was on my TODO list, but I never implemented it. All
the devices currently lack it. I'll include it in next version.

Thanks,
Filip Navara

Re: [Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Filip Navara]

On Wed, Jul 15, 2009 at 5:38 PM, Filip Navara<filip.navara@gmail.com> wrote:
> On Wed, Jul 15, 2009 at 5:33 PM, Blue Swirl<blauwirbel@gmail.com> wrote:
>> On Wed, 15 Jul 09 16:52:12 Central Europe Standard Time, Filip Navara
>> <filip.navara@gmail.com> wrote:
>>> This patch introduces an emulation of the rotary encoder that could be connected
>>>  to GPIO controller.
>>
>> How about reset handling (qemu_register_reset)?
>>
>
> Good point, it was on my TODO list, but I never implemented it. All
> the devices currently lack it. I'll include it in next version.

On second thought the GPIO devices don't need reset handling. In real
hardware the rotary encoder is not affected by reset, so why would it
be affected in QEMU? Unfortunately to get that working correctly the
late_init callbacks, proposed in the devtree patches, are needed.

Best regards,
Filip Navara

Re: [Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Blue Swirl]

On Sat, Jul 18, 2009 at 11:52 AM, Filip Navara<filip.navara@gmail.com> wrote:
> On Wed, Jul 15, 2009 at 5:38 PM, Filip Navara<filip.navara@gmail.com> wrote:
>> On Wed, Jul 15, 2009 at 5:33 PM, Blue Swirl<blauwirbel@gmail.com> wrote:
>>> On Wed, 15 Jul 09 16:52:12 Central Europe Standard Time, Filip Navara
>>> <filip.navara@gmail.com> wrote:
>>>> This patch introduces an emulation of the rotary encoder that could be connected
>>>>  to GPIO controller.
>>>
>>> How about reset handling (qemu_register_reset)?
>>>
>>
>> Good point, it was on my TODO list, but I never implemented it. All
>> the devices currently lack it. I'll include it in next version.
>
> On second thought the GPIO devices don't need reset handling. In real
> hardware the rotary encoder is not affected by reset, so why would it
> be affected in QEMU? Unfortunately to get that working correctly the
> late_init callbacks, proposed in the devtree patches, are needed.

There is still internal state (for example s->extension) that may need reset.

Re: [Qemu-devel] [PATCH 01/14] GPIO rotary encoder implementation

[Filip Navara]

On Sat, Jul 18, 2009 at 11:00 AM, Blue Swirl<blauwirbel@gmail.com> wrote:
> On Sat, Jul 18, 2009 at 11:52 AM, Filip Navara<filip.navara@gmail.com> wrote:
>> On Wed, Jul 15, 2009 at 5:38 PM, Filip Navara<filip.navara@gmail.com> wrote:
>>> On Wed, Jul 15, 2009 at 5:33 PM, Blue Swirl<blauwirbel@gmail.com> wrote:
>>>> On Wed, 15 Jul 09 16:52:12 Central Europe Standard Time, Filip Navara
>>>> <filip.navara@gmail.com> wrote:
>>>>> This patch introduces an emulation of the rotary encoder that could be connected
>>>>>  to GPIO controller.
>>>>
>>>> How about reset handling (qemu_register_reset)?
>>>>
>>>
>>> Good point, it was on my TODO list, but I never implemented it. All
>>> the devices currently lack it. I'll include it in next version.
>>
>> On second thought the GPIO devices don't need reset handling. In real
>> hardware the rotary encoder is not affected by reset, so why would it
>> be affected in QEMU? Unfortunately to get that working correctly the
>> late_init callbacks, proposed in the devtree patches, are needed.
>
> There is still internal state (for example s->extension) that may need reset.
>

s->extension is part of host state actually and I don't think it
should be reset. The only emulated device that resets it is ESCC.
ADB, Musicpal, Syborg, Stellaris and xenfb never reset it (possibly
because reset callbacks are not implemented).

Best regards,
Filip Navara