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Subject: Re: [PATCH] brcmfmac: Obtain reset GPIO
To:     Ulf Hansson <ulf.hansson@linaro.org>,
        Linus Walleij <linus.walleij@linaro.org>
Cc:     Arend van Spriel <aspriel@gmail.com>,
        Franky Lin <franky.lin@broadcom.com>,
        Hante Meuleman <hante.meuleman@broadcom.com>,
        Chi-hsien Lin <chi-hsien.lin@infineon.com>,
        Wright Feng <wright.feng@infineon.com>,
        Chung-hsien Hsu <chung-hsien.hsu@infineon.com>,
        linux-wireless <linux-wireless@vger.kernel.org>
References: <20210509224226.348127-1-linus.walleij@linaro.org>
 <c5370b69-eac2-815e-27cb-f865a7885830@broadcom.com>
 <CAPDyKFq6PEx9YNF5VDjEy2giLOe=NJPxM2KCAWOOQxeGR_3jMw@mail.gmail.com>
From:   Arend van Spriel <arend.vanspriel@broadcom.com>
Message-ID: <30a7bbeb-d588-4780-bd6c-d99f72898138@broadcom.com>
Date:   Mon, 10 May 2021 11:27:12 +0200
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On 5/10/2021 11:14 AM, Ulf Hansson wrote:
> On Mon, 10 May 2021 at 09:37, Arend Van Spriel
> <arend.vanspriel@broadcom.com> wrote:
>>
>> + Uffe
>>
>> On 5/10/2021 12:42 AM, Linus Walleij wrote:
>>> This grabs the reset GPIO and holds it de-asserted, if available.
>>> Asserting this signal will make the SDIO card re-enumerate.
>>
>> looks ok to me, but could this also be done through SDIO power sequence
>> stuff?
> 
> Yes, it certainly looks like that to me. It should be the mmc
> host/core that manages the power on/off thingy for the SDIO card.

Thanks, Uffe

This is not directly power on/off, but a separate "reset" GPIO. However, 
checking in pwrseq_simple.c I see:

struct mmc_pwrseq_simple {
	struct mmc_pwrseq pwrseq;
	bool clk_enabled;
	u32 post_power_on_delay_ms;
	u32 power_off_delay_us;
	struct clk *ext_clk;
	struct gpio_descs *reset_gpios;
};

So the term 'reset_gpios' is also used in pwrseq context.

Regards,
Arend