[PATCH 2/2] serial: pl011: Move uart_register_driver call to device probe
From: Tushar Behera <hidden>
Date: 2014-01-20 09:07:56
Also in:
linux-samsung-soc, lkml
Subsystem:
arm primecell uart pl010 and pl011 drivers, the rest, tty layer and serial drivers · Maintainers:
Russell King, Linus Torvalds, Greg Kroah-Hartman, Jiri Slaby
uart_register_driver call binds the driver to a specific device node through tty_register_driver call. This should typically happen during device probe call. In a multiplatform scenario, it is possible that multiple serial drivers are part of the kernel. Currently the driver registration fails if multiple serial drivers with same default major/minor numbers are included in the kernel. A typical case is observed with amba-pl011 and samsung-uart drivers. Signed-off-by: Tushar Behera <redacted> --- drivers/tty/serial/amba-pl011.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/drivers/tty/serial/amba-pl011.c b/drivers/tty/serial/amba-pl011.c
index d58783d..d4eda24 100644
--- a/drivers/tty/serial/amba-pl011.c
+++ b/drivers/tty/serial/amba-pl011.c@@ -2154,9 +2154,19 @@ static int pl011_probe(struct amba_device *dev, const struct amba_id *id) amba_ports[i] = uap; amba_set_drvdata(dev, uap); + + if (!amba_reg.state) { + ret = uart_register_driver(&amba_reg); + if (ret < 0) { + pr_err("Failed to register AMBA-PL011 driver\n"); + return ret; + } + } + ret = uart_add_one_port(&amba_reg, &uap->port); if (ret) { amba_ports[i] = NULL; + uart_unregister_driver(&amba_reg); pl011_dma_remove(uap); } out:
@@ -2175,6 +2185,7 @@ static int pl011_remove(struct amba_device *dev) amba_ports[i] = NULL; pl011_dma_remove(uap); + uart_unregister_driver(&amba_reg); return 0; }
@@ -2230,22 +2241,14 @@ static struct amba_driver pl011_driver = { static int __init pl011_init(void) { - int ret; printk(KERN_INFO "Serial: AMBA PL011 UART driver\n"); - ret = uart_register_driver(&amba_reg); - if (ret == 0) { - ret = amba_driver_register(&pl011_driver); - if (ret) - uart_unregister_driver(&amba_reg); - } - return ret; + return amba_driver_register(&pl011_driver); } static void __exit pl011_exit(void) { amba_driver_unregister(&pl011_driver); - uart_unregister_driver(&amba_reg); } /*
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1.7.9.5