gpio: max7301: fix the race between chip addition and pins reconfiguration (c557fa3e) · Commits · 戴 / test

There is a small race and code ugliness in max7301: pins are reconfigured after the chip is registered. Swap these calls so that the device is registered in correct state. Also this fixes the comile-time warning about unchecked gpiochip_remove. Signed-off-by:

Dmitry Baryshkov <dbaryshkov@gmail.com> Cc: Juergen Beisert <j.beisert@pengutronix.de> Cc: Guennadi Liakhovetski <g.liakhovetski@pengutronix.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Brownell <david-b@pacbell.net> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

drivers/gpio/max7301.c

+8 −10

Original line number	Diff line number	Diff line
		@@ -255,10 +255,6 @@ static int __devinit max7301_probe(struct spi_device *spi)
		ts->chip.dev = &spi->dev;
		ts->chip.owner = THIS_MODULE;

		ret = gpiochip_add(&ts->chip);
		if (ret)
		goto exit_destroy;

		/*
		* tristate all pins in hardware and cache the
		* register values for later use.
		@@ -269,17 +265,19 @@ static int __devinit max7301_probe(struct spi_device *spi)
		max7301_write(spi, 0x08 + i, 0xAA);
		ts->port_config[i] = 0xAA;
		for (j = 0; j < 4; j++) {
		int idx = ts->chip.base + (i - 1) * 4 + j;
		ret = gpio_direction_input(idx);
		int offset = (i - 1) * 4 + j;
		ret = max7301_direction_input(&ts->chip, offset);
		if (ret)
		goto exit_remove;
		gpio_free(idx);
		goto exit_destroy;
		}
		}

		ret = gpiochip_add(&ts->chip);
		if (ret)
		goto exit_destroy;

		return ret;

		exit_remove:
		gpiochip_remove(&ts->chip);
		exit_destroy:
		dev_set_drvdata(&spi->dev, NULL);
		mutex_destroy(&ts->lock);

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