From:   Javier Martinez Canillas <javierm@redhat.com>
To:     linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org
Cc:     Javier Martinez Canillas <javierm@redhat.com>,
        David Lechner <david@lechnology.com>
Subject: [PATCH 54/60] drm/st7586: Add support for the nomodeset kernel parameter
Date:   Wed, 15 Dec 2021 02:00:02 +0100
Message-Id: <20211215010008.2545520-55-javierm@redhat.com>
In-Reply-To: <20211215010008.2545520-1-javierm@redhat.com>
References: <20211215010008.2545520-1-javierm@redhat.com>
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According to disable Documentation/admin-guide/kernel-parameters.txt, this
parameter can be used to disable kernel modesetting.

DRM drivers will not perform display-mode changes or accelerated rendering
and only the systewm system framebuffer will be available if it was set-up.

But only a few DRM drivers currently check for nomodeset, make this driver
to also support the command line parameter.

Signed-off-by: Javier Martinez Canillas <javierm@redhat.com>
---

 drivers/gpu/drm/tiny/st7586.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/tiny/st7586.c b/drivers/gpu/drm/tiny/st7586.c
index 51b9b9fb3ead..55bf695861c7 100644
--- a/drivers/gpu/drm/tiny/st7586.c
+++ b/drivers/gpu/drm/tiny/st7586.c
@@ -305,6 +305,9 @@ static int st7586_probe(struct spi_device *spi)
 	size_t bufsize;
 	int ret;
 
+	if (drm_firmware_drivers_only())
+		return -ENODEV;
+
 	dbidev = devm_drm_dev_alloc(dev, &st7586_driver,
 				    struct mipi_dbi_dev, drm);
 	if (IS_ERR(dbidev))
-- 
2.33.1