Messages in this thread | | | Date | Fri, 25 Jul 2014 10:33:22 +0200 | From | Jiří Prchal <> | Subject | Re: [PATCH] ARM: at91: at91sam9x5: sets NPCS0 (PA14) back to GPIO |
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I changed manually .config, now it's there: [ 1.195312] spi spi0.0: gpio_request: 23 [ 1.195312] spi spi0.1: gpio_request: 22 [ 1.199218] spi spi0.2: gpio_request: 93 [ 1.203125] spi spi0.3: gpio_request: 14
But still not working.
Dne 25.7.2014 v 09:53 Boris BREZILLON napsal(a): > On Fri, 25 Jul 2014 08:14:40 +0200 > Jiří Prchal <jiri.prchal@aksignal.cz> wrote: > >> >> >> Dne 24.7.2014 v 17:58 Boris BREZILLON napsal(a): >>> On Thu, 24 Jul 2014 17:06:43 +0200 >>> Jiří Prchal <jiri.prchal@aksignal.cz> wrote: >>> >>>> Hi, >>>> >>>> Dne 24.7.2014 v 16:26 Boris BREZILLON napsal(a): >>>>> Hello Jiří, >>>>> >>>>> First of all, please try to use git format-patch when submitting a >>>>> patch to any kernel mailing list. >>>> Sorry for that. >>>>> >>>>> On Thu, 24 Jul 2014 15:38:24 +0200 >>>>> Jiří Prchal <jiri.prchal@aksignal.cz> wrote: >>>>> >>>>>> After ROMBOOT tries boot from flash on SPI0 NPCS0, this NPCS0 (PA14) remains set to PERIPH_A. >>>>>> Because of that, this pin is unusable to something else. >>>>>> This patch sets it back to GPIO. >>>>> >>>>> The policy is to leave pins in an unknown state till some peripheral >>>>> need them. >>>>> >>>>> What are you trying to use this pin for ? >>>> For chip select, but #3. And when SPI communicate with cs0 (PA22), it goes down too (PA14), so 2 devices on bus were >>>> selected. >>> >>> Are you using a 9x5ek board or a custom one, in the latter case could >>> you paste your spi0 node definition ? >> I'm using custom board. My spi node: >> spi0: spi@f0000000 { >> status = "okay"; >> cs-gpios = <&pioA 23 0 >> &pioA 22 0 >> &pioC 29 0 >> &pioA 14 0>; >> >> fm25@0 { >> compatible = "cypress,fm25"; >> spi-max-frequency = <40000000>; >> reg = <0>; >> pagesize = <256>; >> size = <131072>; >> address-width = <24>; >> }; >> /* ADC */ >> spidev@1 { >> compatible = "spidev"; >> reg = <1>; >> spi-max-frequency = <1000000>; >> }; >> /* IO expander for busaddr */ >> spidev@2 { >> compatible = "spidev"; >> reg = <2>; >> label = "busaddr"; >> spi-max-frequency = <10000000>; >> }; >> /* audio codec */ >> codec: codec@3 { >> compatible = "ti,tlv320aic3x"; >> spi-max-frequency = <1000000>; >> reg = <3>; >> }; >> }; >> >> This does not work without patch, because of 2 chips selected at one time because of PA14 is periph_a. Probably ROMBOOT >> changes that. > > Yes, boot code stored in ROM probably mux PA14 to periph A function, > but with your definition PA 14 should be set GPIO mode when the codec > device is created. > > I don't see any obvious error in your definition, could you add a trace > there [1] to see if the gpio is successfully requested ? > Could you also paste the content of /sys/kernel/debug/gpio ? > >>> >>>>> If you just want to use it as a chip select for an spi device, take a >>>>> look at [1]. >>>> At [1] it's OK until as cs0 is for example PA22 and cs1 is PA14. >>> >>> If you want PA14 to control cs1 and PA22 to control cs0 (both >>> configured as GPIOs), you'll have the following definition: >>> >>> cs-gpios = <&pioA 22 0>, <&pioA 14 0>, <0>, <0>; >> See my node. >>> >>>>> >>>>> Here the gpio is requested by the spi core when defining the cs-gpios >>>>> property. The gpio controller then request the listed pins to the pin >>>>> controller (pinctrl driver). >>>> GPIO is not set in driver as GPIO, at least I didn't find it. >>> >>> Take a look at [1], which is set as the gpio_request_enable callback, >>> called by pinctrl core when a gpio is requested. >> But is this called from spi driver when requesting gpios as cs? > > Yes, it's part of the gpio_request process: > gpio_request calls request method on at91 gpio_chip which in turn > calls pinctrl_request_gpio which then calls the gpio_request_enable > method I previously mentioned. > > > Best Regards, > > Boris > > [1]http://lxr.free-electrons.com/source/drivers/spi/spi-atmel.c#L1031 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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