diff options
Diffstat (limited to 'drivers/net/phy/sfp.c')
| -rw-r--r-- | drivers/net/phy/sfp.c | 100 |
1 files changed, 67 insertions, 33 deletions
diff --git a/drivers/net/phy/sfp.c b/drivers/net/phy/sfp.c index 804295ad8a04..7a680b5177f5 100644 --- a/drivers/net/phy/sfp.c +++ b/drivers/net/phy/sfp.c @@ -349,19 +349,11 @@ static int sfp_i2c_read(struct sfp *sfp, bool a2, u8 dev_addr, void *buf, size_t len) { struct i2c_msg msgs[2]; - size_t block_size; + u8 bus_addr = a2 ? 0x51 : 0x50; + size_t block_size = sfp->i2c_block_size; size_t this_len; - u8 bus_addr; int ret; - if (a2) { - block_size = 16; - bus_addr = 0x51; - } else { - block_size = sfp->i2c_block_size; - bus_addr = 0x50; - } - msgs[0].addr = bus_addr; msgs[0].flags = 0; msgs[0].len = 1; @@ -1295,6 +1287,20 @@ static void sfp_hwmon_probe(struct work_struct *work) struct sfp *sfp = container_of(work, struct sfp, hwmon_probe.work); int err, i; + /* hwmon interface needs to access 16bit registers in atomic way to + * guarantee coherency of the diagnostic monitoring data. If it is not + * possible to guarantee coherency because EEPROM is broken in such way + * that does not support atomic 16bit read operation then we have to + * skip registration of hwmon device. + */ + if (sfp->i2c_block_size < 2) { + dev_info(sfp->dev, + "skipping hwmon device registration due to broken EEPROM\n"); + dev_info(sfp->dev, + "diagnostic EEPROM area cannot be read atomically to guarantee data coherency\n"); + return; + } + err = sfp_read(sfp, true, 0, &sfp->diag, sizeof(sfp->diag)); if (err < 0) { if (sfp->hwmon_tries--) { @@ -1655,26 +1661,30 @@ static int sfp_sm_mod_hpower(struct sfp *sfp, bool enable) return 0; } -/* Some modules (Nokia 3FE46541AA) lock up if byte 0x51 is read as a - * single read. Switch back to reading 16 byte blocks unless we have - * a CarlitoxxPro module (rebranded VSOL V2801F). Even more annoyingly, - * some VSOL V2801F have the vendor name changed to OEM. +/* GPON modules based on Realtek RTL8672 and RTL9601C chips (e.g. V-SOL + * V2801F, CarlitoxxPro CPGOS03-0490, Ubiquiti U-Fiber Instant, ...) do + * not support multibyte reads from the EEPROM. Each multi-byte read + * operation returns just one byte of EEPROM followed by zeros. There is + * no way to identify which modules are using Realtek RTL8672 and RTL9601C + * chips. Moreover every OEM of V-SOL V2801F module puts its own vendor + * name and vendor id into EEPROM, so there is even no way to detect if + * module is V-SOL V2801F. Therefore check for those zeros in the read + * data and then based on check switch to reading EEPROM to one byte + * at a time. */ -static int sfp_quirk_i2c_block_size(const struct sfp_eeprom_base *base) +static bool sfp_id_needs_byte_io(struct sfp *sfp, void *buf, size_t len) { - if (!memcmp(base->vendor_name, "VSOL ", 16)) - return 1; - if (!memcmp(base->vendor_name, "OEM ", 16) && - !memcmp(base->vendor_pn, "V2801F ", 16)) - return 1; + size_t i, block_size = sfp->i2c_block_size; - /* Some modules can't cope with long reads */ - return 16; -} + /* Already using byte IO */ + if (block_size == 1) + return false; -static void sfp_quirks_base(struct sfp *sfp, const struct sfp_eeprom_base *base) -{ - sfp->i2c_block_size = sfp_quirk_i2c_block_size(base); + for (i = 1; i < len; i += block_size) { + if (memchr_inv(buf + i, '\0', min(block_size - 1, len - i))) + return false; + } + return true; } static int sfp_cotsworks_fixup_check(struct sfp *sfp, struct sfp_eeprom_id *id) @@ -1718,11 +1728,11 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report) u8 check; int ret; - /* Some modules (CarlitoxxPro CPGOS03-0490) do not support multibyte - * reads from the EEPROM, so start by reading the base identifying - * information one byte at a time. + /* Some SFP modules and also some Linux I2C drivers do not like reads + * longer than 16 bytes, so read the EEPROM in chunks of 16 bytes at + * a time. */ - sfp->i2c_block_size = 1; + sfp->i2c_block_size = 16; ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base)); if (ret < 0) { @@ -1736,6 +1746,33 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report) return -EAGAIN; } + /* Some SFP modules (e.g. Nokia 3FE46541AA) lock up if read from + * address 0x51 is just one byte at a time. Also SFF-8472 requires + * that EEPROM supports atomic 16bit read operation for diagnostic + * fields, so do not switch to one byte reading at a time unless it + * is really required and we have no other option. + */ + if (sfp_id_needs_byte_io(sfp, &id.base, sizeof(id.base))) { + dev_info(sfp->dev, + "Detected broken RTL8672/RTL9601C emulated EEPROM\n"); + dev_info(sfp->dev, + "Switching to reading EEPROM to one byte at a time\n"); + sfp->i2c_block_size = 1; + + ret = sfp_read(sfp, false, 0, &id.base, sizeof(id.base)); + if (ret < 0) { + if (report) + dev_err(sfp->dev, "failed to read EEPROM: %d\n", + ret); + return -EAGAIN; + } + + if (ret != sizeof(id.base)) { + dev_err(sfp->dev, "EEPROM short read: %d\n", ret); + return -EAGAIN; + } + } + /* Cotsworks do not seem to update the checksums when they * do the final programming with the final module part number, * serial number and date code. @@ -1770,9 +1807,6 @@ static int sfp_sm_mod_probe(struct sfp *sfp, bool report) } } - /* Apply any early module-specific quirks */ - sfp_quirks_base(sfp, &id.base); - ret = sfp_read(sfp, false, SFP_CC_BASE + 1, &id.ext, sizeof(id.ext)); if (ret < 0) { if (report) |