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| author | Andy Shevchenko <andriy.shevchenko@linux.intel.com> | 2024-05-03 20:16:03 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-05-04 18:09:30 +0200 |
| commit | 3c089d7ebfcb31ad6fb0530970a32303b1168991 (patch) | |
| tree | 9cac0515b354e6576597ce0e25b169d4b1de1e1c /drivers/tty | |
| parent | d72c3018300e86590b2d5037fe959d040e50cd33 (diff) | |
| download | lwn-3c089d7ebfcb31ad6fb0530970a32303b1168991.tar.gz lwn-3c089d7ebfcb31ad6fb0530970a32303b1168991.zip | |
serial: 8250_exar: Use BIT() in exar_ee_read()
Use BIT() in exar_ee_read() like other functions do.
While at it, explain the EEPROM type and the dummy bit requirement.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Parker Newman <pnewman@connecttech.com>
Link: https://lore.kernel.org/r/20240503171917.2921250-12-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
| -rw-r--r-- | drivers/tty/serial/8250/8250_exar.c | 13 |
1 files changed, 7 insertions, 6 deletions
diff --git a/drivers/tty/serial/8250/8250_exar.c b/drivers/tty/serial/8250/8250_exar.c index 306bc6d7c141..93d2c8dd3cd8 100644 --- a/drivers/tty/serial/8250/8250_exar.c +++ b/drivers/tty/serial/8250/8250_exar.c @@ -324,6 +324,7 @@ static inline u8 exar_ee_read_bit(struct exar8250 *priv) * @ee_addr: Offset of EEPROM to read word from * * Read a single 16bit word from an Exar UART's EEPROM. + * The type of the EEPROM is AT93C46D. * * Return: EEPROM word */ @@ -340,13 +341,13 @@ static u16 exar_ee_read(struct exar8250 *priv, u8 ee_addr) exar_ee_write_bit(priv, 0); // Send address to read from - for (i = 1 << (UART_EXAR_REGB_EE_ADDR_SIZE - 1); i; i >>= 1) - exar_ee_write_bit(priv, (ee_addr & i)); + for (i = UART_EXAR_REGB_EE_ADDR_SIZE - 1; i >= 0; i--) + exar_ee_write_bit(priv, ee_addr & BIT(i)); - // Read data 1 bit at a time - for (i = 0; i <= UART_EXAR_REGB_EE_DATA_SIZE; i++) { - data <<= 1; - data |= exar_ee_read_bit(priv); + // Read data 1 bit at a time starting with a dummy bit + for (i = UART_EXAR_REGB_EE_DATA_SIZE; i >= 0; i--) { + if (exar_ee_read_bit(priv)) + data |= BIT(i); } exar_ee_deselect(priv); |