5.4-stable review patch. If anyone has any objections, please let me know.
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From: Chunyan Zhang chunyan.zhang@unisoc.com
[ Upstream commit 4b7349cb4e26e79429ecd619eb588bf384f69fdb ]
This patch simplifies the process of getting serial port number, with this patch, serial devices must have aliases configured in devicetree.
The serial port searched out via sprd_port array maybe wrong if we don't have serial alias defined in devicetree, and specify console with command line, we would get the wrong port number if other serial ports probe failed before console's. So using aliases is mandatory.
Reviewed-by: Baolin Wang baolin.wang7@gmail.com Signed-off-by: Chunyan Zhang chunyan.zhang@unisoc.com Link: https://lore.kernel.org/r/20200318105049.19623-2-zhang.lyra@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Stable-dep-of: f9608f188756 ("serial: sprd: Assign sprd_port after initialized to avoid wrong access") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/tty/serial/sprd_serial.c | 36 +++++--------------------------- 1 file changed, 5 insertions(+), 31 deletions(-)
diff --git a/drivers/tty/serial/sprd_serial.c b/drivers/tty/serial/sprd_serial.c index 07573de70445c..e6acf2c848f39 100644 --- a/drivers/tty/serial/sprd_serial.c +++ b/drivers/tty/serial/sprd_serial.c @@ -1073,29 +1073,6 @@ static struct uart_driver sprd_uart_driver = { .cons = SPRD_CONSOLE, };
-static int sprd_probe_dt_alias(int index, struct device *dev) -{ - struct device_node *np; - int ret = index; - - if (!IS_ENABLED(CONFIG_OF)) - return ret; - - np = dev->of_node; - if (!np) - return ret; - - ret = of_alias_get_id(np, "serial"); - if (ret < 0) - ret = index; - else if (ret >= ARRAY_SIZE(sprd_port) || sprd_port[ret] != NULL) { - dev_warn(dev, "requested serial port %d not available.\n", ret); - ret = index; - } - - return ret; -} - static int sprd_remove(struct platform_device *dev) { struct sprd_uart_port *sup = platform_get_drvdata(dev); @@ -1173,14 +1150,11 @@ static int sprd_probe(struct platform_device *pdev) int index; int ret;
- for (index = 0; index < ARRAY_SIZE(sprd_port); index++) - if (sprd_port[index] == NULL) - break; - - if (index == ARRAY_SIZE(sprd_port)) - return -EBUSY; - - index = sprd_probe_dt_alias(index, &pdev->dev); + index = of_alias_get_id(pdev->dev.of_node, "serial"); + if (index < 0 || index >= ARRAY_SIZE(sprd_port)) { + dev_err(&pdev->dev, "got a wrong serial alias id %d\n", index); + return -EINVAL; + }
sprd_port[index] = devm_kzalloc(&pdev->dev, sizeof(*sprd_port[index]), GFP_KERNEL);