diff options
author | Alexandre Courbot <acourbot@nvidia.com> | 2013-02-03 01:29:24 +0900 |
---|---|---|
committer | Grant Likely <grant.likely@secretlab.ca> | 2013-02-09 09:20:12 +0000 |
commit | 1a989d0f1de8f5a150b35e1e8181cc1abc139162 (patch) | |
tree | 5d1a3b1009d2ec1ee84abf3d2a120a46b4748f87 /include/asm-generic | |
parent | 0fa2fd9a0d4f1305a54a396d44975894e90eed7b (diff) | |
download | linux-1a989d0f1de8f5a150b35e1e8181cc1abc139162.tar.bz2 |
gpiolib: link all gpio_chips using a list
Add a list member to gpio_chip that allows all chips to be parsed
quickly. The current method requires parsing the entire GPIO integer
space, which is painfully slow. Using a list makes many chip operations
that involve lookup or parsing faster, and also simplifies the code. It
is also necessary to eventually get rid of the global gpio_desc[] array.
The list of gpio_chips is always ordered by base GPIO number to ensure
chips traversal is done in the right order.
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Diffstat (limited to 'include/asm-generic')
-rw-r--r-- | include/asm-generic/gpio.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h index 2034e691c7ab..b562f95cdc2f 100644 --- a/include/asm-generic/gpio.h +++ b/include/asm-generic/gpio.h @@ -53,6 +53,7 @@ struct device_node; * @label: for diagnostics * @dev: optional device providing the GPIOs * @owner: helps prevent removal of modules exporting active GPIOs + * @list: links gpio_chips together for traversal * @request: optional hook for chip-specific activation, such as * enabling module power and clock; may sleep * @free: optional hook for chip-specific deactivation, such as @@ -98,6 +99,7 @@ struct gpio_chip { const char *label; struct device *dev; struct module *owner; + struct list_head list; int (*request)(struct gpio_chip *chip, unsigned offset); |