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-rw-r--r--hw/gpio/pca9552.c481
1 files changed, 481 insertions, 0 deletions
diff --git a/hw/gpio/pca9552.c b/hw/gpio/pca9552.c
new file mode 100644
index 0000000000..27d4db0680
--- /dev/null
+++ b/hw/gpio/pca9552.c
@@ -0,0 +1,481 @@
+/*
+ * PCA9552 I2C LED blinker
+ *
+ * https://www.nxp.com/docs/en/application-note/AN264.pdf
+ *
+ * Copyright (c) 2017-2018, IBM Corporation.
+ * Copyright (c) 2020 Philippe Mathieu-Daudé
+ *
+ * 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 "qemu/module.h"
+#include "qemu/bitops.h"
+#include "hw/qdev-properties.h"
+#include "hw/gpio/pca9552.h"
+#include "hw/gpio/pca9552_regs.h"
+#include "hw/irq.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qapi/visitor.h"
+#include "trace.h"
+#include "qom/object.h"
+
+struct PCA955xClass {
+ /*< private >*/
+ I2CSlaveClass parent_class;
+ /*< public >*/
+
+ uint8_t pin_count;
+ uint8_t max_reg;
+};
+typedef struct PCA955xClass PCA955xClass;
+
+DECLARE_CLASS_CHECKERS(PCA955xClass, PCA955X,
+ TYPE_PCA955X)
+/*
+ * Note: The LED_ON and LED_OFF configuration values for the PCA955X
+ * chips are the reverse of the PCA953X family of chips.
+ */
+#define PCA9552_LED_ON 0x0
+#define PCA9552_LED_OFF 0x1
+#define PCA9552_LED_PWM0 0x2
+#define PCA9552_LED_PWM1 0x3
+#define PCA9552_PIN_LOW 0x0
+#define PCA9552_PIN_HIZ 0x1
+
+static const char *led_state[] = {"on", "off", "pwm0", "pwm1"};
+
+static uint8_t pca955x_pin_get_config(PCA955xState *s, int pin)
+{
+ uint8_t reg = PCA9552_LS0 + (pin / 4);
+ uint8_t shift = (pin % 4) << 1;
+
+ return extract32(s->regs[reg], shift, 2);
+}
+
+/* Return INPUT status (bit #N belongs to GPIO #N) */
+static uint16_t pca955x_pins_get_status(PCA955xState *s)
+{
+ return (s->regs[PCA9552_INPUT1] << 8) | s->regs[PCA9552_INPUT0];
+}
+
+static void pca955x_display_pins_status(PCA955xState *s,
+ uint16_t previous_pins_status)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(s);
+ uint16_t pins_status, pins_changed;
+ int i;
+
+ pins_status = pca955x_pins_get_status(s);
+ pins_changed = previous_pins_status ^ pins_status;
+ if (!pins_changed) {
+ return;
+ }
+ if (trace_event_get_state_backends(TRACE_PCA955X_GPIO_STATUS)) {
+ char *buf = g_newa(char, k->pin_count + 1);
+
+ for (i = 0; i < k->pin_count; i++) {
+ if (extract32(pins_status, i, 1)) {
+ buf[i] = '*';
+ } else {
+ buf[i] = '.';
+ }
+ }
+ buf[i] = '\0';
+ trace_pca955x_gpio_status(s->description, buf);
+ }
+ if (trace_event_get_state_backends(TRACE_PCA955X_GPIO_CHANGE)) {
+ for (i = 0; i < k->pin_count; i++) {
+ if (extract32(pins_changed, i, 1)) {
+ unsigned new_state = extract32(pins_status, i, 1);
+
+ /*
+ * We display the state using the PCA logic ("active-high").
+ * This is not the state of the LED, which signal might be
+ * wired "active-low" on the board.
+ */
+ trace_pca955x_gpio_change(s->description, i,
+ !new_state, new_state);
+ }
+ }
+ }
+}
+
+static void pca955x_update_pin_input(PCA955xState *s)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(s);
+ int i;
+
+ for (i = 0; i < k->pin_count; i++) {
+ uint8_t input_reg = PCA9552_INPUT0 + (i / 8);
+ uint8_t bit_mask = 1 << (i % 8);
+ uint8_t config = pca955x_pin_get_config(s, i);
+ uint8_t old_value = s->regs[input_reg] & bit_mask;
+ uint8_t new_value;
+
+ switch (config) {
+ case PCA9552_LED_ON:
+ /* Pin is set to 0V to turn on LED */
+ s->regs[input_reg] &= ~bit_mask;
+ break;
+ case PCA9552_LED_OFF:
+ /*
+ * Pin is set to Hi-Z to turn off LED and
+ * pullup sets it to a logical 1 unless
+ * external device drives it low.
+ */
+ if (s->ext_state[i] == PCA9552_PIN_LOW) {
+ s->regs[input_reg] &= ~bit_mask;
+ } else {
+ s->regs[input_reg] |= bit_mask;
+ }
+ break;
+ case PCA9552_LED_PWM0:
+ case PCA9552_LED_PWM1:
+ /* TODO */
+ default:
+ break;
+ }
+
+ /* update irq state only if pin state changed */
+ new_value = s->regs[input_reg] & bit_mask;
+ if (new_value != old_value) {
+ qemu_set_irq(s->gpio_out[i], !!new_value);
+ }
+ }
+}
+
+static uint8_t pca955x_read(PCA955xState *s, uint8_t reg)
+{
+ 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:
+ return s->regs[reg];
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: unexpected read to register %d\n",
+ __func__, reg);
+ return 0xFF;
+ }
+}
+
+static void pca955x_write(PCA955xState *s, uint8_t reg, uint8_t data)
+{
+ uint16_t pins_status;
+
+ switch (reg) {
+ case PCA9552_PSC0:
+ case PCA9552_PWM0:
+ case PCA9552_PSC1:
+ case PCA9552_PWM1:
+ s->regs[reg] = data;
+ break;
+
+ case PCA9552_LS0:
+ case PCA9552_LS1:
+ case PCA9552_LS2:
+ case PCA9552_LS3:
+ pins_status = pca955x_pins_get_status(s);
+ s->regs[reg] = data;
+ pca955x_update_pin_input(s);
+ pca955x_display_pins_status(s, pins_status);
+ break;
+
+ case PCA9552_INPUT0:
+ case PCA9552_INPUT1:
+ default:
+ qemu_log_mask(LOG_GUEST_ERROR, "%s: unexpected write to register %d\n",
+ __func__, reg);
+ }
+}
+
+/*
+ * When Auto-Increment is on, the register address is incremented
+ * after each byte is sent to or received by the device. The index
+ * rollovers to 0 when the maximum register address is reached.
+ */
+static void pca955x_autoinc(PCA955xState *s)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(s);
+
+ if (s->pointer != 0xFF && s->pointer & PCA9552_AUTOINC) {
+ uint8_t reg = s->pointer & 0xf;
+
+ reg = (reg + 1) % (k->max_reg + 1);
+ s->pointer = reg | PCA9552_AUTOINC;
+ }
+}
+
+static uint8_t pca955x_recv(I2CSlave *i2c)
+{
+ PCA955xState *s = PCA955X(i2c);
+ uint8_t ret;
+
+ ret = pca955x_read(s, s->pointer & 0xf);
+
+ /*
+ * From the Specs:
+ *
+ * Important Note: When a Read sequence is initiated and the
+ * AI bit is set to Logic Level 1, the Read Sequence MUST
+ * start by a register different from 0.
+ *
+ * I don't know what should be done in this case, so throw an
+ * error.
+ */
+ if (s->pointer == PCA9552_AUTOINC) {
+ qemu_log_mask(LOG_GUEST_ERROR,
+ "%s: Autoincrement read starting with register 0\n",
+ __func__);
+ }
+
+ pca955x_autoinc(s);
+
+ return ret;
+}
+
+static int pca955x_send(I2CSlave *i2c, uint8_t data)
+{
+ PCA955xState *s = PCA955X(i2c);
+
+ /* First byte sent by is the register address */
+ if (s->len == 0) {
+ s->pointer = data;
+ s->len++;
+ } else {
+ pca955x_write(s, s->pointer & 0xf, data);
+
+ pca955x_autoinc(s);
+ }
+
+ return 0;
+}
+
+static int pca955x_event(I2CSlave *i2c, enum i2c_event event)
+{
+ PCA955xState *s = PCA955X(i2c);
+
+ s->len = 0;
+ return 0;
+}
+
+static void pca955x_get_led(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(obj);
+ PCA955xState *s = PCA955X(obj);
+ int led, rc, reg;
+ uint8_t state;
+
+ rc = sscanf(name, "led%2d", &led);
+ if (rc != 1) {
+ error_setg(errp, "%s: error reading %s", __func__, name);
+ return;
+ }
+ if (led < 0 || led > k->pin_count) {
+ error_setg(errp, "%s invalid led %s", __func__, name);
+ return;
+ }
+ /*
+ * Get the LSx register as the qom interface should expose the device
+ * state, not the modeled 'input line' behaviour which would come from
+ * reading the INPUTx reg
+ */
+ reg = PCA9552_LS0 + led / 4;
+ state = (pca955x_read(s, reg) >> ((led % 4) * 2)) & 0x3;
+ visit_type_str(v, name, (char **)&led_state[state], errp);
+}
+
+/*
+ * Return an LED selector register value based on an existing one, with
+ * the appropriate 2-bit state value set for the given LED number (0-3).
+ */
+static inline uint8_t pca955x_ledsel(uint8_t oldval, int led_num, int state)
+{
+ return (oldval & (~(0x3 << (led_num << 1)))) |
+ ((state & 0x3) << (led_num << 1));
+}
+
+static void pca955x_set_led(Object *obj, Visitor *v, const char *name,
+ void *opaque, Error **errp)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(obj);
+ PCA955xState *s = PCA955X(obj);
+ int led, rc, reg, val;
+ uint8_t state;
+ char *state_str;
+
+ if (!visit_type_str(v, name, &state_str, errp)) {
+ return;
+ }
+ rc = sscanf(name, "led%2d", &led);
+ if (rc != 1) {
+ error_setg(errp, "%s: error reading %s", __func__, name);
+ return;
+ }
+ if (led < 0 || led > k->pin_count) {
+ error_setg(errp, "%s invalid led %s", __func__, name);
+ return;
+ }
+
+ for (state = 0; state < ARRAY_SIZE(led_state); state++) {
+ if (!strcmp(state_str, led_state[state])) {
+ break;
+ }
+ }
+ if (state >= ARRAY_SIZE(led_state)) {
+ error_setg(errp, "%s invalid led state %s", __func__, state_str);
+ return;
+ }
+
+ reg = PCA9552_LS0 + led / 4;
+ val = pca955x_read(s, reg);
+ val = pca955x_ledsel(val, led % 4, state);
+ pca955x_write(s, reg, val);
+}
+
+static const VMStateDescription pca9552_vmstate = {
+ .name = "PCA9552",
+ .version_id = 0,
+ .minimum_version_id = 0,
+ .fields = (const VMStateField[]) {
+ VMSTATE_UINT8(len, PCA955xState),
+ VMSTATE_UINT8(pointer, PCA955xState),
+ VMSTATE_UINT8_ARRAY(regs, PCA955xState, PCA955X_NR_REGS),
+ VMSTATE_UINT8_ARRAY(ext_state, PCA955xState, PCA955X_PIN_COUNT_MAX),
+ VMSTATE_I2C_SLAVE(i2c, PCA955xState),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+static void pca9552_reset(DeviceState *dev)
+{
+ PCA955xState *s = PCA955X(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;
+
+ memset(s->ext_state, PCA9552_PIN_HIZ, PCA955X_PIN_COUNT_MAX);
+ pca955x_update_pin_input(s);
+
+ s->pointer = 0xFF;
+ s->len = 0;
+}
+
+static void pca955x_initfn(Object *obj)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(obj);
+ int led;
+
+ assert(k->pin_count <= PCA955X_PIN_COUNT_MAX);
+ for (led = 0; led < k->pin_count; led++) {
+ char *name;
+
+ name = g_strdup_printf("led%d", led);
+ object_property_add(obj, name, "bool", pca955x_get_led, pca955x_set_led,
+ NULL, NULL);
+ g_free(name);
+ }
+}
+
+static void pca955x_set_ext_state(PCA955xState *s, int pin, int level)
+{
+ if (s->ext_state[pin] != level) {
+ uint16_t pins_status = pca955x_pins_get_status(s);
+ s->ext_state[pin] = level;
+ pca955x_update_pin_input(s);
+ pca955x_display_pins_status(s, pins_status);
+ }
+}
+
+static void pca955x_gpio_in_handler(void *opaque, int pin, int level)
+{
+
+ PCA955xState *s = PCA955X(opaque);
+ PCA955xClass *k = PCA955X_GET_CLASS(s);
+
+ assert((pin >= 0) && (pin < k->pin_count));
+ pca955x_set_ext_state(s, pin, level);
+}
+
+static void pca955x_realize(DeviceState *dev, Error **errp)
+{
+ PCA955xClass *k = PCA955X_GET_CLASS(dev);
+ PCA955xState *s = PCA955X(dev);
+
+ if (!s->description) {
+ s->description = g_strdup("pca-unspecified");
+ }
+
+ qdev_init_gpio_out(dev, s->gpio_out, k->pin_count);
+ qdev_init_gpio_in(dev, pca955x_gpio_in_handler, k->pin_count);
+}
+
+static Property pca955x_properties[] = {
+ DEFINE_PROP_STRING("description", PCA955xState, description),
+ DEFINE_PROP_END_OF_LIST(),
+};
+
+static void pca955x_class_init(ObjectClass *klass, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(klass);
+ I2CSlaveClass *k = I2C_SLAVE_CLASS(klass);
+
+ k->event = pca955x_event;
+ k->recv = pca955x_recv;
+ k->send = pca955x_send;
+ dc->realize = pca955x_realize;
+ device_class_set_props(dc, pca955x_properties);
+}
+
+static const TypeInfo pca955x_info = {
+ .name = TYPE_PCA955X,
+ .parent = TYPE_I2C_SLAVE,
+ .instance_init = pca955x_initfn,
+ .instance_size = sizeof(PCA955xState),
+ .class_init = pca955x_class_init,
+ .class_size = sizeof(PCA955xClass),
+ .abstract = true,
+};
+
+static void pca9552_class_init(ObjectClass *oc, void *data)
+{
+ DeviceClass *dc = DEVICE_CLASS(oc);
+ PCA955xClass *pc = PCA955X_CLASS(oc);
+
+ dc->reset = pca9552_reset;
+ dc->vmsd = &pca9552_vmstate;
+ pc->max_reg = PCA9552_LS3;
+ pc->pin_count = 16;
+}
+
+static const TypeInfo pca9552_info = {
+ .name = TYPE_PCA9552,
+ .parent = TYPE_PCA955X,
+ .class_init = pca9552_class_init,
+};
+
+static void pca955x_register_types(void)
+{
+ type_register_static(&pca955x_info);
+ type_register_static(&pca9552_info);
+}
+
+type_init(pca955x_register_types)
generated by cgit v1.2.3 (git 2.26.2) at 2024-11-30 23:27:40 +0000