d3692805f1
This commit removes a superfluous null pointer check. The device is accessed via a label. so in case it is not available a build error arises, but the pointer won't ever be null. Signed-off-by: Thomas Stranger <thomas.stranger@outlook.com>
74 lines
1.6 KiB
C
74 lines
1.6 KiB
C
/*
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* Copyright (c) 2021 Thomas Stranger
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#include <zephyr.h>
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#include <sys/printk.h>
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#include <drivers/eeprom.h>
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#include <device.h>
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#define EERPOM_SAMPLE_OFFSET 0
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#define EERPOM_SAMPLE_MAGIC 0xEE9703
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struct perisistant_values {
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uint32_t magic;
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uint32_t boot_count;
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};
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/*
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* Get a device structure from a devicetree node with alias eeprom-0
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*/
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static const struct device *get_eeprom_device(void)
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{
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const struct device *dev = DEVICE_DT_GET(DT_ALIAS(eeprom_0));
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if (!device_is_ready(dev)) {
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printk("\nError: Device \"%s\" is not ready; "
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"check the driver initialization logs for errors.\n",
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dev->name);
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return NULL;
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}
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printk("Found EEPROM device \"%s\"\n", dev->name);
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return dev;
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}
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void main(void)
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{
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const struct device *eeprom = get_eeprom_device();
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size_t eeprom_size;
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struct perisistant_values values;
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int rc;
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if (eeprom == NULL) {
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return;
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}
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eeprom_size = eeprom_get_size(eeprom);
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printk("Using eeprom with size of: %d.\n", eeprom_size);
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rc = eeprom_read(eeprom, EERPOM_SAMPLE_OFFSET, &values, sizeof(values));
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if (rc < 0) {
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printk("Error: Couldn't read eeprom: err: %d.\n", rc);
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return;
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}
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if (values.magic != EERPOM_SAMPLE_MAGIC) {
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values.magic = EERPOM_SAMPLE_MAGIC;
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values.boot_count = 0;
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}
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values.boot_count++;
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printk("Device booted %d times.\n", values.boot_count);
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rc = eeprom_write(eeprom, EERPOM_SAMPLE_OFFSET, &values, sizeof(values));
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if (rc < 0) {
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printk("Error: Couldn't write eeprom: err:%d.\n", rc);
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return;
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}
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printk("Reset the MCU to see the inceasing boot counter.\n\n");
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}
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