W25Q16JVSSIQ flash power down

[Hkhan7861]

Good day

I am trying to send the flash to power down mode by shifting an instruction code.  The flash is located on spi.  I have found a method to send instruction code in spi_nor.c located in the zephyr drivers.  However, I am struggling to reference this in my project.  I have added 

CONFIG_SPI_NOR=y to my config file and added   "zephyr\drivers\flash\spi_nor.h" to my main.c file but the project doesn't include the functions used in spi_nor.c.  Is there something I need to do to include these functions.

Thank you in advance.

Kind regards,

Hassan

[Hkhan7861]

My intention is to send the flash to DPD mode.  My board file includes this:

&spi3 {

    compatible = "nordic,nrf-spim";

    status = "okay";

    cs-gpios = <&gpio0 7 GPIO_ACTIVE_LOW>;

    pinctrl-0 = <&spi3_default>;

    pinctrl-1 = <&spi3_sleep>;

    pinctrl-names = "default", "sleep";

    w25q32jv: w25q32jv@0 {

        compatible = "jedec,spi-nor";

        reg = <0>;

        spi-max-frequency = <40000000>;

        wp-gpios = <&gpio0 8 GPIO_ACTIVE_LOW>;

        hold-gpios = <&gpio0 10 GPIO_ACTIVE_LOW>;

        size = <0x2000000>;

        has-dpd;

        t-enter-dpd = <3000>;

        t-exit-dpd = <30000>;

        jedec-id = [ ef 40 15 ];

    };

};

and my overlay file contains this:

/ {

    chosen {

        nordic,pm-ext-flash = &w25q32jv;

       

       

    };

   

};

my prj file contains this:

CONFIG_PM_DEVICE=y

By doing some research i've learnt that the device should enter dpd mode if I use

pm_device_action_run(F_dev, PM_DEVICE_ACTION_SUSPEND); 

where F_dev is the flash in question.  Im wondering if this is the right way to do it as i'm not seeing anything in the logs at the moment.

[Hkhan7861]

I've also tried to send the chip to deep power down mode manually by sending one byte of instruction code.

static int spi_deep_power_down(const struct device *const dev,

                               uint8_t opcode, unsigned int access)

{

    const struct spi_nor_config *const driver_cfg = dev->config;

    struct spi_nor_data *const driver_data = dev->data;

    bool is_write = (access & NOR_ACCESS_WRITE) != 0U;

    uint8_t buf[1] = {0};

    buf[0] = opcode;

    const struct spi_buf tx_buf = {

        .buf = &opcode,

        .len = 1

    };

    const struct spi_buf_set tx_set = {

        .buffers = &tx_buf,

        .count = 1,

    };

    // return spi_write_dt(&F_dev, &tx_set);

    return spi_write(F_dev, &driver_cfg->spi, &tx_set);

)

However, ive found that when I use this function, the CS pin never goes low and therefore I cant write the device.  Please assist me in  finding a driver that will work for this if in fact it is the best way to do it.  If not, how do am I able to make the CS pin go low dynamically within the code.

Thank you in advance.

Kind regards,

Hassan