static inline int do_erase_oneblock()

in chips/cfi_cmdset_0020.c [732:888]

• 119 lines of code
• 20 McCabe index (conditional complexity)

static inline int do_erase_oneblock(struct map_info *map, struct flchip *chip, unsigned long adr)
{
	struct cfi_private *cfi = map->fldrv_priv;
	map_word status, status_OK;
	unsigned long timeo;
	int retries = 3;
	DECLARE_WAITQUEUE(wait, current);
	int ret = 0;

	adr += chip->start;

	/* Let's determine this according to the interleave only once */
	status_OK = CMD(0x80);

	timeo = jiffies + HZ;
retry:
	mutex_lock(&chip->mutex);

	/* Check that the chip's ready to talk to us. */
	switch (chip->state) {
	case FL_CFI_QUERY:
	case FL_JEDEC_QUERY:
	case FL_READY:
		map_write(map, CMD(0x70), adr);
		chip->state = FL_STATUS;
		fallthrough;
	case FL_STATUS:
		status = map_read(map, adr);
		if (map_word_andequal(map, status, status_OK, status_OK))
			break;

		/* Urgh. Chip not yet ready to talk to us. */
		if (time_after(jiffies, timeo)) {
			mutex_unlock(&chip->mutex);
			printk(KERN_ERR "waiting for chip to be ready timed out in erase\n");
			return -EIO;
		}

		/* Latency issues. Drop the lock, wait a while and retry */
		mutex_unlock(&chip->mutex);
		cfi_udelay(1);
		goto retry;

	default:
		/* Stick ourselves on a wait queue to be woken when
		   someone changes the status */
		set_current_state(TASK_UNINTERRUPTIBLE);
		add_wait_queue(&chip->wq, &wait);
		mutex_unlock(&chip->mutex);
		schedule();
		remove_wait_queue(&chip->wq, &wait);
		timeo = jiffies + HZ;
		goto retry;
	}

	ENABLE_VPP(map);
	/* Clear the status register first */
	map_write(map, CMD(0x50), adr);

	/* Now erase */
	map_write(map, CMD(0x20), adr);
	map_write(map, CMD(0xD0), adr);
	chip->state = FL_ERASING;

	mutex_unlock(&chip->mutex);
	msleep(1000);
	mutex_lock(&chip->mutex);

	/* FIXME. Use a timer to check this, and return immediately. */
	/* Once the state machine's known to be working I'll do that */

	timeo = jiffies + (HZ*20);
	for (;;) {
		if (chip->state != FL_ERASING) {
			/* Someone's suspended the erase. Sleep */
			set_current_state(TASK_UNINTERRUPTIBLE);
			add_wait_queue(&chip->wq, &wait);
			mutex_unlock(&chip->mutex);
			schedule();
			remove_wait_queue(&chip->wq, &wait);
			timeo = jiffies + (HZ*20); /* FIXME */
			mutex_lock(&chip->mutex);
			continue;
		}

		status = map_read(map, adr);
		if (map_word_andequal(map, status, status_OK, status_OK))
			break;

		/* OK Still waiting */
		if (time_after(jiffies, timeo)) {
			map_write(map, CMD(0x70), adr);
			chip->state = FL_STATUS;
			printk(KERN_ERR "waiting for erase to complete timed out. Xstatus = %lx, status = %lx.\n", status.x[0], map_read(map, adr).x[0]);
			DISABLE_VPP(map);
			mutex_unlock(&chip->mutex);
			return -EIO;
		}

		/* Latency issues. Drop the lock, wait a while and retry */
		mutex_unlock(&chip->mutex);
		cfi_udelay(1);
		mutex_lock(&chip->mutex);
	}

	DISABLE_VPP(map);
	ret = 0;

	/* We've broken this before. It doesn't hurt to be safe */
	map_write(map, CMD(0x70), adr);
	chip->state = FL_STATUS;
	status = map_read(map, adr);

	/* check for lock bit */
	if (map_word_bitsset(map, status, CMD(0x3a))) {
		unsigned char chipstatus = status.x[0];
		if (!map_word_equal(map, status, CMD(chipstatus))) {
			int i, w;
			for (w=0; w<map_words(map); w++) {
				for (i = 0; i<cfi_interleave(cfi); i++) {
					chipstatus |= status.x[w] >> (cfi->device_type * 8);
				}
			}
			printk(KERN_WARNING "Status is not identical for all chips: 0x%lx. Merging to give 0x%02x\n",
			       status.x[0], chipstatus);
		}
		/* Reset the error bits */
		map_write(map, CMD(0x50), adr);
		map_write(map, CMD(0x70), adr);

		if ((chipstatus & 0x30) == 0x30) {
			printk(KERN_NOTICE "Chip reports improper command sequence: status 0x%x\n", chipstatus);
			ret = -EIO;
		} else if (chipstatus & 0x02) {
			/* Protection bit set */
			ret = -EROFS;
		} else if (chipstatus & 0x8) {
			/* Voltage */
			printk(KERN_WARNING "Chip reports voltage low on erase: status 0x%x\n", chipstatus);
			ret = -EIO;
		} else if (chipstatus & 0x20) {
			if (retries--) {
				printk(KERN_DEBUG "Chip erase failed at 0x%08lx: status 0x%x. Retrying...\n", adr, chipstatus);
				timeo = jiffies + HZ;
				chip->state = FL_STATUS;
				mutex_unlock(&chip->mutex);
				goto retry;
			}
			printk(KERN_DEBUG "Chip erase failed at 0x%08lx: status 0x%x\n", adr, chipstatus);
			ret = -EIO;
		}
	}

	wake_up(&chip->wq);
	mutex_unlock(&chip->mutex);
	return ret;
}