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From patchwork Sat Aug 25 08:44:17 2018
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MIME-Version: 1.0
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Subject: gpio: pxa: handle corner case of unprobed device
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X-Patchwork-Submitter: Robert Jarzmik <robert.jarzmik@free.fr>
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X-Patchwork-Id: 962145
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Message-Id: <20180825084417.13526-1-robert.jarzmik@free.fr>
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To: Robert Jarzmik <robert.jarzmik@free.fr>,
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 Linus Walleij <linus.walleij@linaro.org>
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Cc: linux-gpio@vger.kernel.org, linux-kernel@vger.kernel.org
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Date: Sat, 25 Aug 2018 10:44:17 +0200
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From: Robert Jarzmik <robert.jarzmik@free.fr>
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List-Id: <linux-gpio.vger.kernel.org>
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In the corner case where the gpio driver probe fails, for whatever
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reason, the suspend and resume handlers will still be called as they
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have to be registered as syscore operations. This applies as well when
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no probe was called while the driver has been built in the kernel.
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Nicolas tracked this in :
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https://bugzilla.kernel.org/show_bug.cgi?id=200905
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Therefore, add a failsafe in these function, and test if a proper probe
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succeeded and the driver is functional.
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Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
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Reported-by: Nicolas Chauvet <kwizart@gmail.com>
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---
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 drivers/gpio/gpio-pxa.c | 6 ++++++
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 1 file changed, 6 insertions(+)
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diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
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index c18712dabf93..bfe4c5c9f41c 100644
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--- a/drivers/gpio/gpio-pxa.c
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+++ b/drivers/gpio/gpio-pxa.c
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@@ -776,6 +776,9 @@ static int pxa_gpio_suspend(void)
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 	struct pxa_gpio_bank *c;
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 	int gpio;
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+	if (!pchip)
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+		return 0;
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+
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 	for_each_gpio_bank(gpio, c, pchip) {
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 		c->saved_gplr = readl_relaxed(c->regbase + GPLR_OFFSET);
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 		c->saved_gpdr = readl_relaxed(c->regbase + GPDR_OFFSET);
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@@ -794,6 +797,9 @@ static void pxa_gpio_resume(void)
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 	struct pxa_gpio_bank *c;
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 	int gpio;
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+	if (!pchip)
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+		return;
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+
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 	for_each_gpio_bank(gpio, c, pchip) {
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 		/* restore level with set/clear */
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 		writel_relaxed(c->saved_gplr, c->regbase + GPSR_OFFSET);