From: Michal Simek <michal.simek@xxxxxxxxxx> commit 18cc7ac8a28e28cd005c2475f52576cfe10cabfb upstream. This reverts commit 024ca329bfb9a948f76eaff3243e21b7e70182f2. As Johan says, this driver needs a lot more work and these changes are only going in the wrong direction: https://lkml.kernel.org/r/20190523091839.GC568@localhost Reported-by: Johan Hovold <johan@xxxxxxxxxx> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx> Cc: stable <stable@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/1ee35667e36a8efddee381df5fe495ad65f4d15c.1585905873.git.michal.simek@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/tty/serial/xilinx_uartps.c | 95 +++++++++++++++---------------------- 1 file changed, 40 insertions(+), 55 deletions(-) --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -27,6 +27,7 @@ #define CDNS_UART_TTY_NAME "ttyPS" #define CDNS_UART_NAME "xuartps" #define CDNS_UART_MAJOR 0 /* use dynamic node allocation */ +#define CDNS_UART_MINOR 0 /* works best with devtmpfs */ #define CDNS_UART_NR_PORTS 16 #define CDNS_UART_FIFO_SIZE 64 /* FIFO size */ #define CDNS_UART_REGISTER_SPACE 0x1000 @@ -1144,6 +1145,8 @@ static const struct uart_ops cdns_uart_o #endif }; +static struct uart_driver cdns_uart_uart_driver; + #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE /** * cdns_uart_console_putchar - write the character to the FIFO buffer @@ -1283,6 +1286,16 @@ static int cdns_uart_console_setup(struc return uart_set_options(port, co, baud, parity, bits, flow); } + +static struct console cdns_uart_console = { + .name = CDNS_UART_TTY_NAME, + .write = cdns_uart_console_write, + .device = uart_console_device, + .setup = cdns_uart_console_setup, + .flags = CON_PRINTBUFFER, + .index = -1, /* Specified on the cmdline (e.g. console=ttyPS ) */ + .data = &cdns_uart_uart_driver, +}; #endif /* CONFIG_SERIAL_XILINX_PS_UART_CONSOLE */ #ifdef CONFIG_PM_SLEEP @@ -1414,6 +1427,9 @@ static const struct of_device_id cdns_ua }; MODULE_DEVICE_TABLE(of, cdns_uart_of_match); +/* Temporary variable for storing number of instances */ +static int instances; + /** * cdns_uart_probe - Platform driver probe * @pdev: Pointer to the platform device structure @@ -1427,11 +1443,6 @@ static int cdns_uart_probe(struct platfo struct resource *res; struct cdns_uart *cdns_uart_data; const struct of_device_id *match; - struct uart_driver *cdns_uart_uart_driver; - char *driver_name; -#ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE - struct console *cdns_uart_console; -#endif cdns_uart_data = devm_kzalloc(&pdev->dev, sizeof(*cdns_uart_data), GFP_KERNEL); @@ -1441,12 +1452,6 @@ static int cdns_uart_probe(struct platfo if (!port) return -ENOMEM; - cdns_uart_uart_driver = devm_kzalloc(&pdev->dev, - sizeof(*cdns_uart_uart_driver), - GFP_KERNEL); - if (!cdns_uart_uart_driver) - return -ENOMEM; - /* Look for a serialN alias */ id = of_alias_get_id(pdev->dev.of_node, "serial"); if (id < 0) @@ -1457,50 +1462,25 @@ static int cdns_uart_probe(struct platfo return -ENODEV; } - /* There is a need to use unique driver name */ - driver_name = devm_kasprintf(&pdev->dev, GFP_KERNEL, "%s%d", - CDNS_UART_NAME, id); - if (!driver_name) - return -ENOMEM; - - cdns_uart_uart_driver->owner = THIS_MODULE; - cdns_uart_uart_driver->driver_name = driver_name; - cdns_uart_uart_driver->dev_name = CDNS_UART_TTY_NAME; - cdns_uart_uart_driver->major = CDNS_UART_MAJOR; - cdns_uart_uart_driver->minor = id; - cdns_uart_uart_driver->nr = 1; - + if (!cdns_uart_uart_driver.state) { + cdns_uart_uart_driver.owner = THIS_MODULE; + cdns_uart_uart_driver.driver_name = CDNS_UART_NAME; + cdns_uart_uart_driver.dev_name = CDNS_UART_TTY_NAME; + cdns_uart_uart_driver.major = CDNS_UART_MAJOR; + cdns_uart_uart_driver.minor = CDNS_UART_MINOR; + cdns_uart_uart_driver.nr = CDNS_UART_NR_PORTS; #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE - cdns_uart_console = devm_kzalloc(&pdev->dev, sizeof(*cdns_uart_console), - GFP_KERNEL); - if (!cdns_uart_console) - return -ENOMEM; - - strncpy(cdns_uart_console->name, CDNS_UART_TTY_NAME, - sizeof(cdns_uart_console->name)); - cdns_uart_console->index = id; - cdns_uart_console->write = cdns_uart_console_write; - cdns_uart_console->device = uart_console_device; - cdns_uart_console->setup = cdns_uart_console_setup; - cdns_uart_console->flags = CON_PRINTBUFFER; - cdns_uart_console->data = cdns_uart_uart_driver; - cdns_uart_uart_driver->cons = cdns_uart_console; + cdns_uart_uart_driver.cons = &cdns_uart_console; #endif - rc = uart_register_driver(cdns_uart_uart_driver); - if (rc < 0) { - dev_err(&pdev->dev, "Failed to register driver\n"); - return rc; + rc = uart_register_driver(&cdns_uart_uart_driver); + if (rc < 0) { + dev_err(&pdev->dev, "Failed to register driver\n"); + return rc; + } } - cdns_uart_data->cdns_uart_driver = cdns_uart_uart_driver; - - /* - * Setting up proper name_base needs to be done after uart - * registration because tty_driver structure is not filled. - * name_base is 0 by default. - */ - cdns_uart_uart_driver->tty_driver->name_base = id; + cdns_uart_data->cdns_uart_driver = &cdns_uart_uart_driver; match = of_match_node(cdns_uart_of_match, pdev->dev.of_node); if (match && match->data) { @@ -1578,6 +1558,7 @@ static int cdns_uart_probe(struct platfo port->ops = &cdns_uart_ops; port->fifosize = CDNS_UART_FIFO_SIZE; port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_XILINX_PS_UART_CONSOLE); + port->line = id; /* * Register the port. @@ -1609,7 +1590,7 @@ static int cdns_uart_probe(struct platfo console_port = port; #endif - rc = uart_add_one_port(cdns_uart_uart_driver, port); + rc = uart_add_one_port(&cdns_uart_uart_driver, port); if (rc) { dev_err(&pdev->dev, "uart_add_one_port() failed; err=%i\n", rc); @@ -1619,12 +1600,15 @@ static int cdns_uart_probe(struct platfo #ifdef CONFIG_SERIAL_XILINX_PS_UART_CONSOLE /* This is not port which is used for console that's why clean it up */ if (console_port == port && - !(cdns_uart_uart_driver->cons->flags & CON_ENABLED)) + !(cdns_uart_uart_driver.cons->flags & CON_ENABLED)) console_port = NULL; #endif cdns_uart_data->cts_override = of_property_read_bool(pdev->dev.of_node, "cts-override"); + + instances++; + return 0; err_out_pm_disable: @@ -1640,8 +1624,8 @@ err_out_clk_disable: err_out_clk_dis_pclk: clk_disable_unprepare(cdns_uart_data->pclk); err_out_unregister_driver: - uart_unregister_driver(cdns_uart_data->cdns_uart_driver); - + if (!instances) + uart_unregister_driver(cdns_uart_data->cdns_uart_driver); return rc; } @@ -1676,7 +1660,8 @@ static int cdns_uart_remove(struct platf console_port = NULL; #endif - uart_unregister_driver(cdns_uart_data->cdns_uart_driver); + if (!--instances) + uart_unregister_driver(cdns_uart_data->cdns_uart_driver); return rc; }
