Commit 311eab8d authored Jun 12, 2020 by Christophe Leroy Committed by Greg Kroah-Hartman Jun 27, 2020

tty: serial: cpm_uart: Fix behaviour for non existing GPIOs



devm_gpiod_get_index() doesn't return NULL but -ENOENT when the
requested GPIO doesn't exist,  leading to the following messages:

[    2.742468] gpiod_direction_input: invalid GPIO (errorpointer)
[    2.748147] can't set direction for gpio #2: -2
[    2.753081] gpiod_direction_input: invalid GPIO (errorpointer)
[    2.758724] can't set direction for gpio #3: -2
[    2.763666] gpiod_direction_output: invalid GPIO (errorpointer)
[    2.769394] can't set direction for gpio #4: -2
[    2.774341] gpiod_direction_input: invalid GPIO (errorpointer)
[    2.779981] can't set direction for gpio #5: -2
[    2.784545] ff000a20.serial: ttyCPM1 at MMIO 0xfff00a20 (irq = 39, base_baud = 8250000) is a CPM UART

Use devm_gpiod_get_index_optional() instead.

At the same time, handle the error case and properly exit
with an error.

Fixes: 97cbaf2c ("tty: serial: cpm_uart: Convert to use GPIO descriptors")
Cc: stable@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/694a25fdce548c5ee8b060ef6a4b02746b8f25c0.1591986307.git.christophe.leroy@csgroup.eu


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent 48778464

drivers/tty/serial/cpm_uart/cpm_uart_core.c

+8 −1

Original line number	Diff line number	Diff line
		@@ -1215,7 +1215,12 @@ static int cpm_uart_init_port(struct device_node *np,

		pinfo->gpios[i] = NULL;

		gpiod = devm_gpiod_get_index(dev, NULL, i, GPIOD_ASIS);
		gpiod = devm_gpiod_get_index_optional(dev, NULL, i, GPIOD_ASIS);

		if (IS_ERR(gpiod)) {
		ret = PTR_ERR(gpiod);
		goto out_irq;
		}

		if (gpiod) {
		if (i == GPIO_RTS \|\| i == GPIO_DTR)
		@@ -1237,6 +1242,8 @@ static int cpm_uart_init_port(struct device_node *np,

		return cpm_uart_request_port(&pinfo->port);

		out_irq:
		irq_dispose_mapping(pinfo->port.irq);
		out_pram:
		cpm_uart_unmap_pram(pinfo, pram);
		out_mem:

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