From fb1492186276ba52d99b58121b8a9a87f20cc9f3 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Lothar=20Wa=C3=9Fmann?= Date: Thu, 7 Jul 2011 14:50:16 +0200 Subject: [PATCH] gpio/mxc: add missing initialization of basic_mmio_gpio shadow variables MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit The bgpio_init() function does not initialise the shadow register for the GPIO direction register. Thus, when configuring the first GPIO with gpio_set_direction() all other GPIOs of the same bank will be configured as inputs. Since the bgpio layer cannot know whether the register is readable, the initialisation should be done by the caller of bgpio_init(). Also, the 'data' shadow variable that is used inside basic_mmio_gpio to cache the current value of the GPIO_DR register is initialised from the GPIO_PSR register within bgpio_init(). Thus when setting the output value of a certain GPIO, the other GPIO outputs of the same bank will be set or cleared depending on the pin state of the GPIO inputs during bgpio_init(). Signed-off-by: Lothar Waßmann Signed-off-by: Grant Likely --- drivers/gpio/gpio-mxc.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c index 2f6a81b8f12e..71ba316854ca 100644 --- a/drivers/gpio/gpio-mxc.c +++ b/drivers/gpio/gpio-mxc.c @@ -305,6 +305,8 @@ static int __devinit mxc_gpio_probe(struct platform_device *pdev) goto out_iounmap; port->bgc.gc.base = pdev->id * 32; + port->bgc.dir = port->bgc.read_reg(port->bgc.reg_dir); + port->bgc.data = port->bgc.read_reg(port->bgc.reg_set); err = gpiochip_add(&port->bgc.gc); if (err) -- 2.20.1