From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Wed, 30 Jan 2013 17:05:21 +0100 Subject: [U-Boot] [PATCH 06/10] mx23_olinuxino: Add support for status LED In-Reply-To: References: <1359548001-14278-1-git-send-email-otavio@ossystems.com.br> <201301301639.26621.marex@denx.de> Message-ID: <201301301705.22076.marex@denx.de> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Dear Otavio Salvador, > On Wed, Jan 30, 2013 at 1:39 PM, Marek Vasut wrote: > > Dear Otavio Salvador, > > > >> On Wed, Jan 30, 2013 at 12:13 PM, Marek Vasut wrote: > >> > Dear Otavio Salvador, > >> > > >> >> This allow user to know if the bootloader is running, even without a > >> >> serial console. > >> >> > >> >> Signed-off-by: Otavio Salvador > >> > > >> > Uh oh, how does this know which GPIO to toggle to drive the led this > >> > time ? > >> > >> The problem wasn't the code but me. I wasn't able to find the right > >> GPIO number at that time. > > > > This is not my question. My question is how does this toggle the GPIO for > > the LED? > > gpio_led driver (drivers/misc/gpio_led.c) does it. > > ... > void __led_init(led_id_t mask, int state) > { > gpio_request(mask, "gpio_led"); > gpio_direction_output(mask, state == STATUS_LED_ON); > } > > void __led_set(led_id_t mask, int state) > { > gpio_set_value(mask, state == STATUS_LED_ON); > } > ... Ok, this didn't explain much to me. > > Moreover, you never set the LED GPIO as output. > > The driver handles it by itself. Oh ok. Now that I did read through the code, I have few more questions: Why can't STATUS_LED_BIT be the MX23_PAD_SSP1_DETECT__GPIO_2_1 now? Did you test CMD_LED, does it work when toggling the LED? Best regards, Marek Vasut