+ ret = clk_prepare_enable(efuse->clk);
+ if (ret < 0) {
+ dev_err(efuse->dev, "failed to prepare/enable efuse clk\n");
+ return ret;
+ }
+
+ 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(sizeof(*buf) * addr_len * RK3399_NBYTES, GFP_KERNEL);
+ if (!buf) {
+ clk_disable_unprepare(efuse->clk);
+ return -ENOMEM;
+ }
+
+ writel(RK3399_LOAD | RK3399_PGENB | RK3399_STROBSFTSEL | RK3399_RSB,
+ efuse->base + REG_EFUSE_CTRL);
+ udelay(1);
+ while (addr_len--) {
+ writel(readl(efuse->base + REG_EFUSE_CTRL) | RK3399_STROBE |
+ ((addr_start++ & RK3399_A_MASK) << RK3399_A_SHIFT),
+ efuse->base + REG_EFUSE_CTRL);
+ udelay(1);
+ out_value = readl(efuse->base + REG_EFUSE_DOUT);
+ writel(readl(efuse->base + REG_EFUSE_CTRL) & (~RK3399_STROBE),
+ efuse->base + REG_EFUSE_CTRL);
+ udelay(1);
+
+ memcpy(&buf[i], &out_value, RK3399_NBYTES);
+ i += RK3399_NBYTES;
+ }
+
+ /* Switch to standby mode */
+ writel(RK3399_PD | RK3399_CSB, efuse->base + REG_EFUSE_CTRL);
+
+ memcpy(val, buf + addr_offset, bytes);
+
+ kfree(buf);
+
+ clk_disable_unprepare(efuse->clk);
+
+ return 0;
+}