[Qemu-devel] [PATCH v2 5/6] misc: add pca9552 LED blinker model

["Cédric Le Goater" <clg@kaod.org>]

Specs are available here :

  https://www.nxp.com/docs/en/data-sheet/PCA9552.pdf

This is a simple model supporting the basic registers for led and GPIO
mode. The device also supports two blinking rates but not the model
yet.

Signed-off-by: Cédric Le Goater <clg@kaod.org>
---
 default-configs/arm-softmmu.mak |   1 +
 hw/misc/Makefile.objs           |   1 +
 hw/misc/pca9552.c               | 212 ++++++++++++++++++++++++++++++++++++++++
 include/hw/misc/pca9552.h       |  32 ++++++
 4 files changed, 246 insertions(+)
 create mode 100644 hw/misc/pca9552.c
 create mode 100644 include/hw/misc/pca9552.h

diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
index bbdd3c1d8b7f..17b8fc323f27 100644
--- a/default-configs/arm-softmmu.mak
+++ b/default-configs/arm-softmmu.mak
@@ -16,6 +16,7 @@ CONFIG_TSC2005=y
 CONFIG_LM832X=y
 CONFIG_TMP105=y
 CONFIG_TMP421=y
+CONFIG_PCA9552=y
 CONFIG_STELLARIS=y
 CONFIG_STELLARIS_INPUT=y
 CONFIG_STELLARIS_ENET=y
diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs
index 29fb922cefc6..33ba1d6642f9 100644
--- a/hw/misc/Makefile.objs
+++ b/hw/misc/Makefile.objs
@@ -7,6 +7,7 @@ common-obj-$(CONFIG_SGA) += sga.o
 common-obj-$(CONFIG_ISA_TESTDEV) += pc-testdev.o
 common-obj-$(CONFIG_PCI_TESTDEV) += pci-testdev.o
 common-obj-$(CONFIG_EDU) += edu.o
+common-obj-$(CONFIG_PCA9552) += pca9552.o
 
 common-obj-y += unimp.o
 
diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c
new file mode 100644
index 000000000000..22460f4c14fe
--- /dev/null
+++ b/hw/misc/pca9552.c
@@ -0,0 +1,212 @@
+/*
+ * PCA9552 I2C LED blinker
+ *
+ * Copyright (c) 2017, IBM Corporation.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qemu/log.h"
+#include "hw/hw.h"
+#include "hw/misc/pca9552.h"
+
+#define PCA9552_INPUT0   0 /* read only input register 0 */
+#define PCA9552_INPUT1   1 /* read only input register 1  */
+#define PCA9552_PSC0     2 /* read/write frequency prescaler 0 */
+#define PCA9552_PWM0     3 /* read/write PWM register 0 */
+#define PCA9552_PSC1     4 /* read/write frequency prescaler 1 */
+#define PCA9552_PWM1     5 /* read/write PWM register 1 */
+#define PCA9552_LS0      6 /* read/write LED0 to LED3 selector */
+#define PCA9552_LS1      7 /* read/write LED4 to LED7 selector */
+#define PCA9552_LS2      8 /* read/write LED8 to LED11 selector */
+#define PCA9552_LS3      9 /* read/write LED12 to LED15 selector */
+
+#define PCA9552_LED_ON   0x0
+#define PCA9552_LED_OFF  0x1
+#define PCA9552_LED_PWM0 0x2
+#define PCA9552_LED_PWM1 0x3
+
+static uint8_t pca9552_pin_get_config(PCA9552State *s, int pin)
+{
+    uint8_t reg   = PCA9552_LS0 + (pin / 4);
+    uint8_t shift = (pin % 4) << 1;
+
+    return (s->regs[reg] >> shift) & 0x3;
+}
+
+static void pca9552_update_pin_input(PCA9552State *s)
+{
+    int i;
+
+    for (i = 0; i < 16; i++) {
+        uint8_t input_reg = PCA9552_INPUT0 + (i / 8);
+        uint8_t input_shift = (i % 8);
+        uint8_t config = pca9552_pin_get_config(s, i);
+
+        switch (config) {
+        case PCA9552_LED_ON:
+            s->regs[input_reg] |= 1 << input_shift;
+            break;
+        case PCA9552_LED_OFF:
+            s->regs[input_reg] &= ~(1 << input_shift);
+            break;
+        case PCA9552_LED_PWM0:
+        case PCA9552_LED_PWM1:
+            /* ??? */
+        default:
+            break;
+        }
+    }
+}
+
+static void pca9552_read(PCA9552State *s)
+{
+    uint8_t reg = s->pointer & 0xf;
+
+    s->len = 0;
+
+    switch (reg) {
+    case PCA9552_INPUT0:
+    case PCA9552_INPUT1:
+    case PCA9552_PSC0:
+    case PCA9552_PWM0:
+    case PCA9552_PSC1:
+    case PCA9552_PWM1:
+    case PCA9552_LS0:
+    case PCA9552_LS1:
+    case PCA9552_LS2:
+    case PCA9552_LS3:
+        s->buf[s->len++] = s->regs[reg];
+        break;
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: unexpected read to register %d\n",
+                      __func__, reg);
+    }
+}
+
+static void pca9552_write(PCA9552State *s)
+{
+    uint8_t reg = s->pointer & 0xf;
+
+    switch (reg) {
+    case PCA9552_PSC0:
+    case PCA9552_PWM0:
+    case PCA9552_PSC1:
+    case PCA9552_PWM1:
+        s->regs[reg] = s->buf[0];
+        break;
+
+    case PCA9552_LS0:
+    case PCA9552_LS1:
+    case PCA9552_LS2:
+    case PCA9552_LS3:
+        s->regs[reg] = s->buf[0];
+        pca9552_update_pin_input(s);
+        break;
+
+    case PCA9552_INPUT0:
+    case PCA9552_INPUT1:
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: unexpected write to register %d\n",
+                      __func__, reg);
+    }
+}
+
+static int pca9552_recv(I2CSlave *i2c)
+{
+    PCA9552State *s = PCA9552(i2c);
+
+    if (s->len < sizeof(s->buf)) {
+        return s->buf[s->len++];
+    } else {
+        return 0xff;
+    }
+}
+
+static int pca9552_send(I2CSlave *i2c, uint8_t data)
+{
+    PCA9552State *s = PCA9552(i2c);
+
+    if (s->len == 0) {
+        s->pointer = data;
+        s->len++;
+    } else {
+        if (s->len <= sizeof(s->buf)) {
+            s->buf[s->len - 1] = data;
+        }
+        s->len++;
+        pca9552_write(s);
+    }
+
+    return 0;
+}
+
+static int pca9552_event(I2CSlave *i2c, enum i2c_event event)
+{
+    PCA9552State *s = PCA9552(i2c);
+
+    if (event == I2C_START_RECV) {
+        pca9552_read(s);
+    }
+
+    s->len = 0;
+    return 0;
+}
+
+static const VMStateDescription pca9552_vmstate = {
+    .name = "PCA9552",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT8(len, PCA9552State),
+        VMSTATE_UINT8(pointer, PCA9552State),
+        VMSTATE_UINT8_ARRAY(buf, PCA9552State, 1),
+        VMSTATE_UINT8_ARRAY(regs, PCA9552State, PCA9552_NR_REGS),
+        VMSTATE_I2C_SLAVE(i2c, PCA9552State),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void pca9552_reset(DeviceState *dev)
+{
+    PCA9552State *s = PCA9552(dev);
+
+    s->regs[PCA9552_PSC0] = 0xFF;
+    s->regs[PCA9552_PWM0] = 0x80;
+    s->regs[PCA9552_PSC1] = 0xFF;
+    s->regs[PCA9552_PWM1] = 0x80;
+    s->regs[PCA9552_LS0] = 0x55; /* all OFF */
+    s->regs[PCA9552_LS1] = 0x55;
+    s->regs[PCA9552_LS2] = 0x55;
+    s->regs[PCA9552_LS3] = 0x55;
+
+    pca9552_update_pin_input(s);
+}
+
+static void pca9552_class_init(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
+
+    k->event = pca9552_event;
+    k->recv = pca9552_recv;
+    k->send = pca9552_send;
+    dc->reset = pca9552_reset;
+    dc->vmsd = &pca9552_vmstate;
+}
+
+static const TypeInfo pca9552_info = {
+    .name          = TYPE_PCA9552,
+    .parent        = TYPE_I2C_SLAVE,
+    .instance_size = sizeof(PCA9552State),
+    .class_init    = pca9552_class_init,
+};
+
+static void pca9552_register_types(void)
+{
+    type_register_static(&pca9552_info);
+}
+
+type_init(pca9552_register_types)
diff --git a/include/hw/misc/pca9552.h b/include/hw/misc/pca9552.h
new file mode 100644
index 000000000000..875467725526
--- /dev/null
+++ b/include/hw/misc/pca9552.h
@@ -0,0 +1,32 @@
+/*
+ * PCA9552 I2C LED blinker
+ *
+ * Copyright (c) 2017, IBM Corporation.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ */
+#ifndef PCA9552_H
+#define PCA9552_H
+
+#include "hw/i2c/i2c.h"
+
+#define TYPE_PCA9552 "pca9552"
+#define PCA9552(obj) OBJECT_CHECK(PCA9552State, (obj), TYPE_PCA9552)
+
+
+#define PCA9552_NR_REGS 10
+
+typedef struct PCA9552State {
+    /*< private >*/
+    I2CSlave i2c;
+    /*< public >*/
+
+    uint8_t len;
+    uint8_t pointer;
+    uint8_t buf[1]; /* just to remember how to handle a larger buffer */
+
+    uint8_t regs[PCA9552_NR_REGS];
+} PCA9552State;
+
+#endif
-- 
2.13.5