Hi Milo,
Thanks for the update.
On 06/29/2015 02:39 AM, Milo Kim wrote:
LP55xx driver uses not firmware file but raw data to load program through
the firmware interface.(Documents/leds/leds-lp55xx.txt)
For example, here is how to run blinking green channel pattern.
(The second engine is seleted and MUX is mapped to 'RGB' mode)
echo 2 > /sys/bus/i2c/devices/xxxx/select_engine
echo "RGB" > /sys/bus/i2c/devices/xxxx/engine_mux
echo 1 > /sys/class/firmware/lp5562/loading
echo "4000600040FF6000" > /sys/class/firmware/lp5562/data
echo 0 > /sys/class/firmware/lp5562/loading
echo 1 > /sys/bus/i2c/devices/xxxx/run_engine
However, '/sys/class/firmware/<device name>' is not created after the
firmware loader user helper was introduced.
This feature is used in the case below.
As soon as the firmware download is requested by the driver, firmware
class subsystem tries to find the binary file.
If it gets failed, then it just falls back to user helper to load
raw data manually. Here, you can see the device file under
/sys/class/firmware/.
To make it happen, LP55xx driver requires two configurations.
1. Enable CONFIG_FW_LOADER_USER_HELPER_FALLBACK in Kconfig
2. Set option, 'FW_OPT_USERHELPER' on requesting the firmware data.
It means the second option should be 'false' in
request_firmware_nowait().
This option enables to load firmware data manually by calling
fw_load_from_user_helper().
Cc: Bryan Wu <cooloney@xxxxxxxxx>
Cc: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
Cc: linux-leds@xxxxxxxxxxxxxxx
Signed-off-by: Milo Kim <milo.kim@xxxxxx>
---
drivers/leds/Kconfig | 1 +
drivers/leds/leds-lp55xx-common.c | 2 +-
2 files changed, 2 insertions(+), 1 deletion(-)
diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig
index 966b960..a39d608 100644
--- a/drivers/leds/Kconfig
+++ b/drivers/leds/Kconfig
@@ -206,6 +206,7 @@ config LEDS_LP55XX_COMMON
tristate "Common Driver for TI/National LP5521/5523/55231/5562/8501"
depends on LEDS_LP5521 || LEDS_LP5523 || LEDS_LP5562 || LEDS_LP8501
select FW_LOADER
+ select FW_LOADER_USER_HELPER_FALLBACK
help
This option supports common operations for LP5521/5523/55231/5562/8501
devices.
diff --git a/drivers/leds/leds-lp55xx-common.c b/drivers/leds/leds-lp55xx-common.c
index 77c26bc..96d51e9 100644
--- a/drivers/leds/leds-lp55xx-common.c
+++ b/drivers/leds/leds-lp55xx-common.c
@@ -223,7 +223,7 @@ static int lp55xx_request_firmware(struct lp55xx_chip *chip)
const char *name = chip->cl->name;
struct device *dev = &chip->cl->dev;
- return request_firmware_nowait(THIS_MODULE, true, name, dev,
+ return request_firmware_nowait(THIS_MODULE, false, name, dev,
GFP_KERNEL, chip, lp55xx_firmware_loaded);
}
Acked-by: Jacek Anaszewski <j.anaszewski@xxxxxxxxxxx>
--
Best Regards,
Jacek Anaszewski
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