static int rockchip_rk3328_efuse_read()

in rockchip-efuse.c [95:148]

• 46 lines of code
• 5 McCabe index (conditional complexity)

static int rockchip_rk3328_efuse_read(void *context, unsigned int offset,
				      void *val, size_t bytes)
{
	struct rockchip_efuse_chip *efuse = context;
	unsigned int addr_start, addr_end, addr_offset, addr_len;
	u32 out_value, status;
	u8 *buf;
	int ret, i = 0;

	ret = clk_prepare_enable(efuse->clk);
	if (ret < 0) {
		dev_err(efuse->dev, "failed to prepare/enable efuse clk\n");
		return ret;
	}

	/* 128 Byte efuse, 96 Byte for secure, 32 Byte for non-secure */
	offset += RK3328_SECURE_SIZES;
	addr_start = rounddown(offset, RK3399_NBYTES) / RK3399_NBYTES;
	addr_end = roundup(offset + bytes, RK3399_NBYTES) / RK3399_NBYTES;
	addr_offset = offset % RK3399_NBYTES;
	addr_len = addr_end - addr_start;

	buf = kzalloc(array3_size(addr_len, RK3399_NBYTES, sizeof(*buf)),
		      GFP_KERNEL);
	if (!buf) {
		ret = -ENOMEM;
		goto nomem;
	}

	while (addr_len--) {
		writel(RK3328_AUTO_RD | RK3328_AUTO_ENB |
		       ((addr_start++ & RK3399_A_MASK) << RK3399_A_SHIFT),
		       efuse->base + RK3328_AUTO_CTRL);
		udelay(4);
		status = readl(efuse->base + RK3328_INT_STATUS);
		if (!(status & RK3328_INT_FINISH)) {
			ret = -EIO;
			goto err;
		}
		out_value = readl(efuse->base + RK3328_DOUT);
		writel(RK3328_INT_FINISH, efuse->base + RK3328_INT_STATUS);

		memcpy(&buf[i], &out_value, RK3399_NBYTES);
		i += RK3399_NBYTES;
	}

	memcpy(val, buf + addr_offset, bytes);
err:
	kfree(buf);
nomem:
	clk_disable_unprepare(efuse->clk);

	return ret;
}