diff options
Diffstat (limited to 'hw/misc')
| -rw-r--r-- | hw/misc/Makefile.objs | 1 | ||||
| -rw-r--r-- | hw/misc/pca9552.c | 240 |
2 files changed, 241 insertions, 0 deletions
diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs index 00e834d0f0..ecd8d61098 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-$(CONFIG_PCA9552) += pca9552.o common-obj-y += unimp.o common-obj-$(CONFIG_FW_CFG_DMA) += vmcoreinfo.o diff --git a/hw/misc/pca9552.c b/hw/misc/pca9552.c new file mode 100644 index 0000000000..9775d5274a --- /dev/null +++ b/hw/misc/pca9552.c @@ -0,0 +1,240 @@ +/* + * PCA9552 I2C LED blinker + * + * https://www.nxp.com/docs/en/application-note/AN264.pdf + * + * Copyright (c) 2017-2018, 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" +#include "hw/misc/pca9552_regs.h" + +#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 extract32(s->regs[reg], shift, 2); +} + +static void pca9552_update_pin_input(PCA9552State *s) +{ + int i; + + for (i = 0; i < s->nr_leds; 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: + /* TODO */ + default: + break; + } + } +} + +static uint8_t pca9552_read(PCA9552State *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 pca9552_write(PCA9552State *s, uint8_t reg, uint8_t data) +{ + 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: + s->regs[reg] = data; + 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); + } +} + +/* + * 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 pca9552_autoinc(PCA9552State *s) +{ + if (s->pointer != 0xFF && s->pointer & PCA9552_AUTOINC) { + uint8_t reg = s->pointer & 0xf; + + reg = (reg + 1) % (s->max_reg + 1); + s->pointer = reg | PCA9552_AUTOINC; + } +} + +static int pca9552_recv(I2CSlave *i2c) +{ + PCA9552State *s = PCA9552(i2c); + uint8_t ret; + + ret = pca9552_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__); + } + + pca9552_autoinc(s); + + return ret; +} + +static int pca9552_send(I2CSlave *i2c, uint8_t data) +{ + PCA9552State *s = PCA9552(i2c); + + /* First byte sent by is the register address */ + if (s->len == 0) { + s->pointer = data; + s->len++; + } else { + pca9552_write(s, s->pointer & 0xf, data); + + pca9552_autoinc(s); + } + + return 0; +} + +static int pca9552_event(I2CSlave *i2c, enum i2c_event event) +{ + PCA9552State *s = PCA9552(i2c); + + 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(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); + + s->pointer = 0xFF; + s->len = 0; +} + +static void pca9552_initfn(Object *obj) +{ + PCA9552State *s = PCA9552(obj); + + /* If support for the other PCA955X devices are implemented, these + * constant values might be part of class structure describing the + * PCA955X device + */ + s->max_reg = PCA9552_LS3; + s->nr_leds = 16; +} + +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_init = pca9552_initfn, + .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) |