2014-03-03 12:11 GMT+01:00 Richard Genoud <noreply.rgenoud@xxxxxxxxx>: > The USART controller on sam9x5 chips (and also all AT91/SAMA5 chips > but at91rm9200) are not capable of handling DTR/DSR/DCD/RI signal. > Moreover, even if the controller can handle CTS/RTS, the dedicated > CTS/RTS pins are already muxed for other peripherals (LCDC/EMAC/MMC). > > So this patchset adds the possibility to control those lines via GPIO, > as it is done for RTS in the patch "switch atmel serial to use gpiolib" > > As it was suggested by Alexander Shiyan, I made that available for > every board. > > Patch 1 implements the generic helpers to control modem lines via GPIO > Patch 2 implements modem control lines in atmel_serial atmel_serial. > Patch 3 implement the interrupts of CTS/DSR/DCD/RI. > > This is based on next-20140303 + [PATCH v3 5/7] ARM: at91: gpio: implement get_direction > (It has been acked by Linus, but I don't think it has been applied in a tree yet) > > Tested on at91sam9g35, with a null modem cable between 2 serial ports, > one with CTS/RTS controlled by the USART controller, the other via GPIO, > full duplex transfers. > Did some tests also with null modem cables on a PC, and with real modems. > > Updates from v4: > - patches "tty/serial: at91: remove unused open/close hooks" and > "tty/serial: at91: use dev_err instead of printk" have been picked > by Greg on tty tree. > - As Alexander pointed out, IS_ERR_OR_NULL() was replaced by a simple > check againts NULL in patch 1/3 > - in path 1/3, a warning is produced instead of an error when we can't set > the direction of a GPIO. > > Updates from v3: > - add static keyword on struct uart0_gpios_table. > - add use an index at the mctrl_gpio_init() function to make it > usable by driver that allocates several ports at once. > - hide struct gpio_desc from users. > - patch "pinctrl: at91: implement get_direction" has been picked by Linus. > - patch "ARM: at91: gpio: implement get_direction" has been acked by Linus. > > Updates from v2: > - remove UART_GPIO_MIN/UART_GPIO_MAX_INPUT and use a direction > boolean instead. > - implement get_direction in at91 pinctrl and mach-at91/gpio.c. > - remove the get_mctrl_gpio_name() function that was used for > logs only. > - split atmel_serial.c patch in 2. > - use a gpio lookup table to declare modem gpios in platform > devices boards. So there's no more special case for platform > data gpios in atmel_serial.c. > > Updates from v1: > - Instead of controlling modem signal only on atmel board, the > code is now available for every board. > - The active low flag from device tree is now used. I'll send a v6 with (last) corrections next week. -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
