kernel/linux.git/drivers/tty/serial/max310x.c, branch v4.9.331

serial: max310x: unregister uart driver in case of failure and abort

2021-06-03T06:23:31+00:00

[ Upstream commit 3890e3dea315f1a257d1b940a2a4e2fa16a7b095 ] The macro "spi_register_driver" invokes the function "__spi_register_driver()" which has a return type of int and can fail, returning a negative value in such a case. This is currently ignored and the init() function yields success even if the spi driver failed to register. Fix this by collecting the return value of "__spi_register_driver()" and also unregister the uart driver in case of failure. Cc: Jiri Slaby Signed-off-by: Atul Gopinathan Link: https://lore.kernel.org/r/20210503115736.2104747-12-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

serial: max310x: Fix tx_empty() callback

2019-12-05T14:34:41+00:00

[ Upstream commit a8da3c7873ea57acb8f9cea58c0af477522965aa ] Function max310x_tx_empty() accesses the IRQSTS register, which is cleared by IC when reading, so if there is an interrupt status, we will lose it. This patch implement the transmitter check only by the current FIFO level. Signed-off-by: Alexander Shiyan Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

tty: max310x: Fix invalid baudrate divisors calculator

2019-08-04T07:33:36+00:00

[ Upstream commit 35240ba26a932b279a513f66fa4cabfd7af55221 ] Current calculator doesn't do it' job quite correct. First of all the max310x baud-rates generator supports the divisor being less than 16. In this case the x2/x4 modes can be used to double or quadruple the reference frequency. But the current baud-rate setter function just filters all these modes out by the first condition and setups these modes only if there is a clocks-baud division remainder. The former doesn't seem right at all, since enabling the x2/x4 modes causes the line noise tolerance reduction and should be only used as a last resort to enable a requested too high baud-rate. Finally the fraction is supposed to be calculated from D = Fref/(c*baud) formulae, but not from D % 16, which causes the precision loss. So to speak the current baud-rate calculator code works well only if the baud perfectly fits to the uart reference input frequency. Lets fix the calculator by implementing the algo fully compliant with the fractional baud-rate generator described in the datasheet: D = Fref / (c*baud), where c={16,8,4} is the x1/x2/x4 rate mode respectively, Fref - reference input frequency. The divisor fraction is calculated from the same formulae, but making sure it is found with a resolution of 0.0625 (four bits). Signed-off-by: Serge Semin Signed-off-by: Greg Kroah-Hartman Signed-off-by: Sasha Levin

tty: max310x: Fix external crystal register setup

2019-06-11T10:22:42+00:00

commit 5d24f455c182d5116dd5db8e1dc501115ecc9c2c upstream. The datasheet states: Bit 4: ClockEnSet the ClockEn bit high to enable an external clocking (crystal or clock generator at XIN). Set the ClockEn bit to 0 to disable clocking Bit 1: CrystalEnSet the CrystalEn bit high to enable the crystal oscillator. When using an external clock source at XIN, CrystalEn must be set low. The bit 4, MAX310X_CLKSRC_EXTCLK_BIT, should be set and was not. This was required to make the MAX3107 with an external crystal on our board able to send or receive data. Signed-off-by: Joe Burmeister Cc: stable Signed-off-by: Greg Kroah-Hartman

serial: max310x: Fix to avoid potential NULL pointer dereference

2019-04-03T04:24:18+00:00

commit 3a10e3dd52e80b9a97a3346020024d17b2c272d6 upstream. of_match_device can return a NULL pointer when matching device is not found. This patch avoids a scenario causing NULL pointer derefernce. Signed-off-by: Aditya Pakki Cc: stable Signed-off-by: Greg Kroah-Hartman

serial: max310x: Set IRQF_TRIGGER_FALLING flag when dev.of_node is not NULL

2016-09-15T10:35:49+00:00

When dev.of_node is not NULL, we also need to set IRQF_TRIGGER_FALLING flag, otherwise it may cause uncertain interrupts. Signed-off-by: Liu Xiang Signed-off-by: Greg Kroah-Hartman

serial: max310x: Assign port line automatically

2016-06-25T20:55:35+00:00

This patch makes assignment of port line automatically, so now user allow to use several MAX310X chips. Signed-off-by: Alexander Shiyan Signed-off-by: Greg Kroah-Hartman

serial: max310x: Unregister UARTs on error

2016-06-25T20:55:35+00:00

Add uart_remove_one_port() for error path. Signed-off-by: Alexander Shiyan Signed-off-by: Greg Kroah-Hartman

serial: max310x: Remove duplicate bits definition

2016-06-25T20:55:35+00:00

Signed-off-by: Alexander Shiyan Signed-off-by: Greg Kroah-Hartman

serial: max310x: Register UART driver at module_init

2016-06-25T20:55:35+00:00

This patch moves UART registration at module_init initcall, so this should helps to add multiple chip support in the future. Signed-off-by: Alexander Shiyan Signed-off-by: Greg Kroah-Hartman