On 08/08/2013 09:08 PM, Kim, Milo wrote:
> From the viewpoint of a GPIO consumer, we don't care the base GPIO number.
> That is required when a GPIO controller is added.
> Just check '/sys/kernel/debug/gpio' and use available GPIOs for LEDs.
Hmm. I'm using leds-gpio, and it certainly does seem to care about GPIO
numbers. As a point of reference, here's what I'm doing to set up my
drive activity LEDs:
#define N5550_ICH_GPIO_BASE 195
#define N5550_DISK_ACT_0_GPIO (N5550_ICH_GPIO_BASE + 0)
#define N5550_DISK_ACT_1_GPIO (N5550_ICH_GPIO_BASE + 2)
#define N5550_DISK_ACT_2_GPIO (N5550_ICH_GPIO_BASE + 3)
#define N5550_DISK_ACT_3_GPIO (N5550_ICH_GPIO_BASE + 4)
#define N5550_DISK_ACT_4_GPIO (N5550_ICH_GPIO_BASE + 5)
static struct gpio_led n5550_disk_act_leds[5] = {
{
.name = "n5550:green:disk-act-0",
.default_trigger = "thecus-ahci-0",
.gpio = N5550_DISK_ACT_0_GPIO,
.active_low = 1,
.default_state = LEDS_GPIO_DEFSTATE_OFF,
},
{
.name = "n5550:green:disk-act-1",
.default_trigger = "thecus-ahci-1",
.gpio = N5550_DISK_ACT_1_GPIO,
.active_low = 1,
.default_state = LEDS_GPIO_DEFSTATE_OFF,
},
{
.name = "n5550:green:disk-act-2",
.default_trigger = "thecus-ahci-2",
.gpio = N5550_DISK_ACT_2_GPIO,
.active_low = 1,
.default_state = LEDS_GPIO_DEFSTATE_OFF,
},
{
.name = "n5550:green:disk-act-3",
.default_trigger = "thecus-ahci-3",
.gpio = N5550_DISK_ACT_3_GPIO,
.active_low = 1,
.default_state = LEDS_GPIO_DEFSTATE_OFF,
},
{
.name = "n5550:green:disk-act-4",
.default_trigger = "thecus-ahci-4",
.gpio = N5550_DISK_ACT_4_GPIO,
.active_low = 1,
.default_state = LEDS_GPIO_DEFSTATE_OFF,
},
};
As you can see, every LED has a GPIO number (.gpio), which comes from
the chip's GPIO base, and that number gets hardcoded into the setup
code. If the ich_gpio driver ever "dynamically" selects a base other
than 195, the LEDs won't work.
I just seems very fragile, and I can't help thinking that there must be
a better way. Maybe a module parameter ...
Thanks!
--
========================================================================
Ian Pilcher arequipeno@xxxxxxxxx
Sometimes there's nothing left to do but crash and burn...or die trying.
========================================================================
--
To unsubscribe from this list: send the line "unsubscribe linux-leds" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
