Merge "mtd: msm_qpic_nand: Support for partial page read"

	return err;

}

/**

 * msm_nand_read_partial_page() - read partial page

 * @mtd: pointer to mtd info

 * @from: start address of the page

 * @ops: pointer to mtd_oob_ops

 *

 * Reads a page into a bounce buffer and copies the required

 * number of bytes to actual buffer. The pages that are aligned

 * do not use bounce buffer.

 */

static int msm_nand_read_partial_page(struct mtd_info *mtd,

		loff_t from, struct mtd_oob_ops *ops)

{

	int err = 0;

	unsigned char *actual_buf;

	unsigned char *bounce_buf;

	loff_t aligned_from;

	loff_t offset;

	size_t len;

	size_t actual_len;

	actual_len = ops->len;

	actual_buf = ops->datbuf;

	bounce_buf = kmalloc(mtd->writesize, GFP_KERNEL);

	if (!bounce_buf) {

		pr_err("%s: could not allocate memory\n", __func__);

		err = -ENOMEM;

		goto out;

	}

	/* Get start address of page to read from */

	ops->len = mtd->writesize;

	offset = from & (mtd->writesize - 1);

	aligned_from = from - offset;

	for (;;) {

		bool no_copy = false;

		len = mtd->writesize - offset;

		if (len > actual_len)

			len = actual_len;

		if (offset == 0 && len == mtd->writesize)

			no_copy = true;

		ops->datbuf = no_copy ? actual_buf : bounce_buf;

		err = msm_nand_read_oob(mtd, aligned_from, ops);

		if (err < 0)

			break;

		if (!no_copy)

			memcpy(actual_buf, bounce_buf + offset, len);

		actual_len -= len;

		ops->retlen += len;

		if (actual_len == 0)

			break;

		actual_buf += len;

		offset = 0;

		aligned_from += mtd->writesize;

	}

	kfree(bounce_buf);

out:

	return err;

}

/*

 * Function that gets called from upper layers such as MTD/YAFFS2 to read a

 * page with only main data.

	ops.ooblen = 0;

	ops.datbuf = buf;

	ops.oobbuf = NULL;

	if (!(from & (mtd->writesize - 1)) && !(len % mtd->writesize))

		/* read pages on page boundary */

		ret = msm_nand_read_oob(mtd, from, &ops);

	else

		ret = msm_nand_read_partial_page(mtd, from, &ops);

	*retlen = ops.retlen;

	return ret;

}