redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

gpio: of: fix GPIO drivers with multiple gpio_chip for a single node 

Sylvain Lemieux reports the LPC32xx GPIO driver is broken since
commit 762c2e46c0 ("gpio: of: remove of_gpiochip_and_xlate() and
struct gg_data").  Probably, gpio-etraxfs.c and gpio-davinci.c are
broken too.

Those drivers register multiple gpio_chip that are associated to a
single OF node, and their own .of_xlate() checks if the passed
gpio_chip is valid.

Now, the problem is of_find_gpiochip_by_node() returns the first
gpio_chip found to match the given node.  So, .of_xlate() fails,
except for the first GPIO bank.

Reverting the commit could be a solution, but I do not want to go
back to the mess of struct gg_data.  Another solution here is to
take the match by a node pointer and the success of .of_xlate().
It is a bit clumsy to call .of_xlate twice; for gpio_chip matching
and for really getting the gpio_desc index.  Perhaps, our long-term
goal might be to convert the drivers to single chip registration,
but this commit will solve the problem until then.

Fixes: 762c2e46c0 ("gpio: of: remove of_gpiochip_and_xlate() and struct gg_data")
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reported-by: Sylvain Lemieux <slemieux.tyco@gmail.com>
Tested-by: David Lechner <david@lechnology.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
hifive-unleashed-5.1
Masahiro Yamada 2016-10-25 10:47:44 +09:00 committed by Linus Walleij
parent 953b956a2e
commit c7e9d39831
1 changed files with 9 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

14
drivers/gpio/gpiolib-of.c
View File

@ -26,14 +26,18 @@
#include "gpiolib.h"
static int of_gpiochip_match_node(struct gpio_chip *chip, void *data)
static int of_gpiochip_match_node_and_xlate(struct gpio_chip *chip, void *data)
{
return chip->gpiodev->dev.of_node == data;
struct of_phandle_args *gpiospec = data;
return chip->gpiodev->dev.of_node == gpiospec->np &&
chip->of_xlate(chip, gpiospec, NULL) >= 0;
}
static struct gpio_chip *of_find_gpiochip_by_node(struct device_node *np)
static struct gpio_chip *of_find_gpiochip_by_xlate(
struct of_phandle_args *gpiospec)
{
return gpiochip_find(np, of_gpiochip_match_node);
return gpiochip_find(gpiospec, of_gpiochip_match_node_and_xlate);
}
static struct gpio_desc *of_xlate_and_get_gpiod_flags(struct gpio_chip *chip,
@ -79,7 +83,7 @@ struct gpio_desc *of_get_named_gpiod_flags(struct device_node *np,
return ERR_PTR(ret);
}
chip = of_find_gpiochip_by_node(gpiospec.np);
chip = of_find_gpiochip_by_xlate(&gpiospec);
if (!chip) {
desc = ERR_PTR(-EPROBE_DEFER);
goto out;