Re: [PATCH v10 char-misc-next 1/2] misc: microchip: pci1xxxx: Add support to read and write into PCI1XXXX OTP via NVMEM sysfs

From: Michael Walle
Date: Tue Apr 25 2023 - 03:35:08 EST


Hi,

+static int pci1xxxx_otp_read(void *priv_t, unsigned int off,
+ void *buf_t, size_t count)
+{
+ struct pci1xxxx_otp_eeprom_device *priv = priv_t;
+ void __iomem *rb = priv->reg_base;
+ char *buf = buf_t;
+ u32 regval;
+ u32 byte;
+ int ret;
+ u8 data;
+
+ if (off >= priv->nvmem_config_otp.size)
+ return -EFAULT;
+
+ if ((off + count) > priv->nvmem_config_otp.size)
+ count = priv->nvmem_config_otp.size - off;
+
+ ret = set_sys_lock(priv);
+ if (ret)
+ return ret;
+
+ for (byte = 0; byte < count; byte++) {
+ otp_device_set_address(priv, (u16)(off + byte));
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_FUNC_CMD_OFFSET));
+ writel(data | OTP_FUNC_RD_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_FUNC_CMD_OFFSET));
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_CMD_GO_OFFSET));
+ writel(data | OTP_CMD_GO_BIT,
+ rb + MMAP_OTP_OFFSET(OTP_CMD_GO_OFFSET));
+
+ ret = read_poll_timeout(readl, regval,
+ !(regval & OTP_STATUS_BUSY_BIT),
+ STATUS_READ_DELAY_US,
+ STATUS_READ_TIMEOUT_US, true,
+ rb + MMAP_OTP_OFFSET(OTP_STATUS_OFFSET));
+
+ data = readl(rb + MMAP_OTP_OFFSET(OTP_PASS_FAIL_OFFSET));
+ if (ret < 0 || data & OTP_FAIL_BIT)
+ return -EIO;

Don't you need to release the lock?

+
+ buf[byte] = readl(rb + MMAP_OTP_OFFSET(OTP_RD_DATA_OFFSET));
+ }
+ release_sys_lock(priv);
+
+ return byte;
+}