[PATCH v12 10/35] gpu: host1x: Add host1x_channel_stop()

From: Dmitry Osipenko <digetx@gmail.com>
To: "Thierry Reding" <thierry.reding@gmail.com>,
	"Jonathan Hunter" <jonathanh@nvidia.com>,
	"Ulf Hansson" <ulf.hansson@linaro.org>,
	"Viresh Kumar" <vireshk@kernel.org>,
	"Stephen Boyd" <sboyd@kernel.org>,
	"Peter De Schrijver" <pdeschrijver@nvidia.com>,
	"Mikko Perttunen" <mperttunen@nvidia.com>,
	"Peter Chen" <peter.chen@kernel.org>,
	"Lee Jones" <lee.jones@linaro.org>,
	"Uwe Kleine-König" <u.kleine-koenig@pengutronix.de>,
	"Nishanth Menon" <nm@ti.com>,
	"Adrian Hunter" <adrian.hunter@intel.com>,
	"Rob Herring" <robh+dt@kernel.org>,
	"Michael Turquette" <mturquette@baylibre.com>
Cc: linux-kernel@vger.kernel.org, linux-tegra@vger.kernel.org,
	linux-pm@vger.kernel.org, linux-usb@vger.kernel.org,
	linux-staging@lists.linux.dev, linux-pwm@vger.kernel.org,
	linux-mmc@vger.kernel.org, dri-devel@lists.freedesktop.org,
	devicetree@vger.kernel.org, linux-clk@vger.kernel.org,
	Mark Brown <broonie@kernel.org>,
	Vignesh Raghavendra <vigneshr@ti.com>,
	Richard Weinberger <richard@nod.at>,
	Miquel Raynal <miquel.raynal@bootlin.com>,
	Lucas Stach <dev@lynxeye.de>, Stefan Agner <stefan@agner.ch>,
	Mauro Carvalho Chehab <mchehab@kernel.org>,
	David Heidelberg <david@ixit.cz>
Subject: [PATCH v12 10/35] gpu: host1x: Add host1x_channel_stop()
Date: Mon, 20 Sep 2021 21:11:20 +0300	[thread overview]
Message-ID: <20210920181145.19543-11-digetx@gmail.com> (raw)
In-Reply-To: <20210920181145.19543-1-digetx@gmail.com>

Add host1x_channel_stop() which waits till channel becomes idle and then
stops the channel hardware. This is needed for supporting suspend/resume
by host1x drivers since the hardware state is lost after power-gating,
thus the channel needs to be stopped before client enters into suspend.

Tested-by: Peter Geis <pgwipeout@gmail.com> # Ouya T30
Tested-by: Paul Fertser <fercerpav@gmail.com> # PAZ00 T20
Tested-by: Nicolas Chauvet <kwizart@gmail.com> # PAZ00 T20 and TK1 T124
Tested-by: Matt Merhar <mattmerhar@protonmail.com> # Ouya T30
Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
 drivers/gpu/host1x/channel.c | 8 ++++++++
 include/linux/host1x.h       | 1 +
 2 files changed, 9 insertions(+)

diff --git a/drivers/gpu/host1x/channel.c b/drivers/gpu/host1x/channel.c
index 4cd212bb570d..2a9a3a8d5931 100644
--- a/drivers/gpu/host1x/channel.c
+++ b/drivers/gpu/host1x/channel.c
@@ -75,6 +75,14 @@ struct host1x_channel *host1x_channel_get_index(struct host1x *host,
 	return ch;
 }
 
+void host1x_channel_stop(struct host1x_channel *channel)
+{
+	struct host1x *host = dev_get_drvdata(channel->dev->parent);
+
+	host1x_hw_cdma_stop(host, &channel->cdma);
+}
+EXPORT_SYMBOL(host1x_channel_stop);
+
 static void release_channel(struct kref *kref)
 {
 	struct host1x_channel *channel =
diff --git a/include/linux/host1x.h b/include/linux/host1x.h
index 7bccf589aba7..66473b5be0af 100644
--- a/include/linux/host1x.h
+++ b/include/linux/host1x.h
@@ -181,6 +181,7 @@ struct host1x_job;
 
 struct host1x_channel *host1x_channel_request(struct host1x_client *client);
 struct host1x_channel *host1x_channel_get(struct host1x_channel *channel);
+void host1x_channel_stop(struct host1x_channel *channel);
 void host1x_channel_put(struct host1x_channel *channel);
 int host1x_job_submit(struct host1x_job *job);
 
-- 
2.32.0

