Re: [Qemu-arm] [PATCH v6 7/8] misc: add pca9552 LED blinker model

[Philippe Mathieu-Daudé]

Hi Cédric,

On 10/19/2017 01:35 PM, Cédric Le Goater wrote:
> Specs are available here :
> 
>     https://www.nxp.com/docs/en/application-note/AN264.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 <address@hidden>
> Reviewed-by: Peter Maydell <address@hidden>
> ---
> 
>  Changes since v3:
> 
>  - introduced auto-increment support
>  - removed the buffer collecting bytes on the bus
>  - improved reset
>  - used extract32
>  - added a unit test
> 
>  Changes since v2:
> 
>  - removed comments on the I2C buffer size, but kept the array. I did
>    not want to rewrite the buffer handling
> 
>  default-configs/arm-softmmu.mak |   1 +
>  hw/misc/Makefile.objs           |   1 +
>  hw/misc/pca9552.c               | 259 
> ++++++++++++++++++++++++++++++++++++++++
>  include/hw/misc/pca9552.h       |  33 +++++

If you mind using scripts/git.orderfile the review'd get easier :)

>  tests/Makefile.include          |   2 +
>  tests/pca9552-test.c            | 131 ++++++++++++++++++++
>  6 files changed, 427 insertions(+)
>  create mode 100644 hw/misc/pca9552.c
>  create mode 100644 include/hw/misc/pca9552.h
>  create mode 100644 tests/pca9552-test.c
> 
> diff --git a/default-configs/arm-softmmu.mak b/default-configs/arm-softmmu.mak
> index 5059d134c816..d868d1095a6c 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 e8f0a02f35af..e4e22880dbbc 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..70ce6f038da2
> --- /dev/null
> +++ b/hw/misc/pca9552.c
> @@ -0,0 +1,259 @@
> +/*
> + * PCA9552 I2C LED blinker
> + *
> + *     https://www.nxp.com/docs/en/application-note/AN264.pdf
> + *
> + * 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"
> +
> +/*
> + * Bits [0:3] are used to address a specific register.
> + */
> +#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 */

Since you use those in your test, can you move them to "hw/misc/pca9552.h"?

> +
> +/*
> + * Bit [4] is used to activate the Auto-Increment option of the
> + * register address
> + */
> +#define PCA9552_AUTOINC  (1 << 4)

ditto

> +
> +#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;

Looks a bit weird, why not use PCA9552_NR_REGS here so pca9552_autoinc()
becomes simply:

    reg += 1;
    reg %= s->max_reg;

?

> +    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)
> diff --git a/include/hw/misc/pca9552.h b/include/hw/misc/pca9552.h
> new file mode 100644
> index 000000000000..5df8d6407ca7
> --- /dev/null
> +++ b/include/hw/misc/pca9552.h
> @@ -0,0 +1,33 @@
> +/*
> + * 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

This could be an enum (or not, matter of taste).

> +
> +typedef struct PCA9552State {
> +    /*< private >*/
> +    I2CSlave i2c;
> +    /*< public >*/
> +
> +    uint8_t len;
> +    uint8_t pointer;
> +
> +    uint8_t regs[PCA9552_NR_REGS];
> +    uint8_t max_reg;
> +    uint8_t nr_leds;
> +} PCA9552State;
> +
> +#endif
> diff --git a/tests/Makefile.include b/tests/Makefile.include
> index 4ca15e681703..8ac2595c8512 100644
> --- a/tests/Makefile.include
> +++ b/tests/Makefile.include
> @@ -347,6 +347,7 @@ check-qtest-sparc64-y = tests/endianness-test$(EXESUF)
>  check-qtest-sparc64-y += tests/prom-env-test$(EXESUF)
>  
>  check-qtest-arm-y = tests/tmp105-test$(EXESUF)
> +check-qtest-arm-y += tests/pca9552-test$(EXESUF)
>  check-qtest-arm-y += tests/ds1338-test$(EXESUF)
>  check-qtest-arm-y += tests/m25p80-test$(EXESUF)
>  gcov-files-arm-y += hw/misc/tmp105.c
> @@ -739,6 +740,7 @@ tests/bios-tables-test$(EXESUF): tests/bios-tables-test.o 
> \
>       tests/boot-sector.o tests/acpi-utils.o $(libqos-obj-y)
>  tests/pxe-test$(EXESUF): tests/pxe-test.o tests/boot-sector.o $(libqos-obj-y)
>  tests/tmp105-test$(EXESUF): tests/tmp105-test.o $(libqos-omap-obj-y)
> +tests/pca9552-test$(EXESUF): tests/pca9552-test.o $(libqos-omap-obj-y)
>  tests/ds1338-test$(EXESUF): tests/ds1338-test.o $(libqos-imx-obj-y)
>  tests/m25p80-test$(EXESUF): tests/m25p80-test.o
>  tests/i440fx-test$(EXESUF): tests/i440fx-test.o $(libqos-pc-obj-y)
> diff --git a/tests/pca9552-test.c b/tests/pca9552-test.c
> new file mode 100644
> index 000000000000..53414452a12e
> --- /dev/null
> +++ b/tests/pca9552-test.c
> @@ -0,0 +1,131 @@
> +/*
> + * QTest testcase for the PCA9552 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 "hw/misc/pca9552.h"

> +#include "libqtest.h"
> +#include "libqos/i2c.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_AUTOINC  (1 << 4)
> +
> +
> +#define OMAP2_I2C_1_BASE 0x48070000

Can you define that in "hw/arm/omap.h" ?

> +
> +#define PCA9552_TEST_ID   "pca9552-test"
> +#define PCA9552_TEST_ADDR 0x60
> +
> +static I2CAdapter *i2c;
> +
> +static uint8_t pca9552_get8(I2CAdapter *i2c, uint8_t addr, uint8_t reg)
> +{
> +    uint8_t resp[1];
> +    i2c_send(i2c, addr, &reg, 1);
> +    i2c_recv(i2c, addr, resp, 1);
> +    return resp[0];
> +}
> +
> +static void pca9552_set8(I2CAdapter *i2c, uint8_t addr, uint8_t reg,
> +                         uint8_t value)
> +{
> +    uint8_t cmd[2];
> +    uint8_t resp[1];
> +
> +    cmd[0] = reg;
> +    cmd[1] = value;
> +    i2c_send(i2c, addr, cmd, 2);
> +    i2c_recv(i2c, addr, resp, 1);
> +    g_assert_cmphex(resp[0], ==, cmd[1]);
> +}
> +
> +static void receive_autoinc(void)
> +{
> +    uint8_t resp;
> +    uint8_t reg = PCA9552_LS0 | PCA9552_AUTOINC;
> +
> +    i2c_send(i2c, PCA9552_TEST_ADDR, &reg, 1);
> +
> +    /* PCA9552_LS0 */
> +    i2c_recv(i2c, PCA9552_TEST_ADDR, &resp, 1);
> +    g_assert_cmphex(resp, ==, 0x54);
> +
> +    /* PCA9552_LS1 */
> +    i2c_recv(i2c, PCA9552_TEST_ADDR, &resp, 1);
> +    g_assert_cmphex(resp, ==, 0x55);
> +
> +    /* PCA9552_LS2 */
> +    i2c_recv(i2c, PCA9552_TEST_ADDR, &resp, 1);
> +    g_assert_cmphex(resp, ==, 0x55);
> +
> +    /* PCA9552_LS3 */
> +    i2c_recv(i2c, PCA9552_TEST_ADDR, &resp, 1);
> +    g_assert_cmphex(resp, ==, 0x54);
> +}
> +
> +static void send_and_receive(void)
> +{
> +    uint8_t value;
> +
> +    value = pca9552_get8(i2c, PCA9552_TEST_ADDR, PCA9552_LS0);
> +    g_assert_cmphex(value, ==, 0x55);
> +
> +    value = pca9552_get8(i2c, PCA9552_TEST_ADDR, PCA9552_INPUT0);
> +    g_assert_cmphex(value, ==, 0x0);
> +
> +    /* Switch on LED 0 */
> +    pca9552_set8(i2c, PCA9552_TEST_ADDR, PCA9552_LS0, 0x54);
> +    value = pca9552_get8(i2c, PCA9552_TEST_ADDR, PCA9552_LS0);
> +    g_assert_cmphex(value, ==, 0x54);
> +
> +    value = pca9552_get8(i2c, PCA9552_TEST_ADDR, PCA9552_INPUT0);
> +    g_assert_cmphex(value, ==, 0x01);
> +
> +    /* Switch on LED 12 */
> +    pca9552_set8(i2c, PCA9552_TEST_ADDR, PCA9552_LS3, 0x54);
> +    value = pca9552_get8(i2c, PCA9552_TEST_ADDR, PCA9552_LS3);
> +    g_assert_cmphex(value, ==, 0x54);
> +
> +    value = pca9552_get8(i2c, PCA9552_TEST_ADDR, PCA9552_INPUT1);
> +    g_assert_cmphex(value, ==, 0x10);
> +}
> +
> +int main(int argc, char **argv)
> +{
> +    QTestState *s = NULL;
> +    int ret;
> +
> +    g_test_init(&argc, &argv, NULL);
> +
> +    s = qtest_start("-machine n800 "
> +                    "-device pca9552,bus=i2c-bus.0,id=" PCA9552_TEST_ID
> +                    ",address=0x60");
> +    i2c = omap_i2c_create(OMAP2_I2C_1_BASE);
> +
> +    qtest_add_func("/pca9552/tx-rx", send_and_receive);
> +    qtest_add_func("/pca9552/rx-autoinc", receive_autoinc);
> +
> +    ret = g_test_run();
> +
> +    if (s) {
> +        qtest_quit(s);
> +    }
> +    g_free(i2c);
> +
> +    return ret;
> +}
> 

If Peter accept to queue 1-6, I'd appreciate if you can address my few
suggestions then resend 7-8; else if you don't have time:
Reviewed-by: Philippe Mathieu-Daudé <address@hidden>

Regards,

Phil.