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

[Cédric Le Goater]

On 10/20/2017 04:58 AM, Philippe Mathieu-Daudé wrote:
> 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 :)

I didn't know about it. I will take a look.
>>  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"?

yes I could stuff them under "hw/misc/pca9552_reg.h" probably.

> 
>> +
>> +/*
>> + * 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;
> 
> ?

because I expect someone (me, maybe) to add support for the 
PCA9550,1,3 devices and, in that case, regs[] could be shared 
and PCA9552_NR_REGS would represent the maximum of the maximum 
number of registers for all devices.
 
>> +    s->nr_leds = 16;

this value would change also for each device.

 
>> +}
>> +
>> +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).

a define is fine IMO.

>> +
>> +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" ?

I suppose I can to share it with tmp105-test.c

>> +
>> +#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>

I rather address your suggestions in follow ups if you don't mind.

Thanks for the review,

C.

> Regards,
> 
> Phil.
>