[PATCH AUTOSEL 4.19 30/66] drm/sun4i: dsi: Use NULL to signify "no panel"

[PATCH AUTOSEL 4.19 30/66] drm/sun4i: dsi: Use NULL to signify "no panel"

[Sasha Levin]

From: Samuel Holland <samuel@sholland.org>

[ Upstream commit 0e4e3fb4901d19f49e5c0a582f383b10dda8d1c5 ]

The continued use of an ERR_PTR to signify "no panel" outside of
sun6i_dsi_attach is confusing because it is a double negative. Because
the connector always reports itself as connected, there is also the
possibility of sending an ERR_PTR to drm_panel_get_modes(), which would
crash.

Solve both of these by only storing the panel pointer if it is valid.

Fixes: 133add5b5ad4 ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller support")
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20200211072858.30784-2-samuel@sholland.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
index 79eb11cd185d1..bc9454a562877 100644
--- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
+++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
@@ -642,7 +642,7 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
 	sun6i_dphy_init(dsi->dphy, device->lanes);
 	sun6i_dphy_power_on(dsi->dphy, device->lanes);
 
-	if (!IS_ERR(dsi->panel))
+	if (dsi->panel)
 		drm_panel_prepare(dsi->panel);
 
 	/*
@@ -657,7 +657,7 @@ static void sun6i_dsi_encoder_enable(struct drm_encoder *encoder)
 	 * ordering on the panels I've tested it with, so I guess this
 	 * will do for now, until that IP is better understood.
 	 */
-	if (!IS_ERR(dsi->panel))
+	if (dsi->panel)
 		drm_panel_enable(dsi->panel);
 
 	sun6i_dsi_start(dsi, DSI_START_HSC);
@@ -673,7 +673,7 @@ static void sun6i_dsi_encoder_disable(struct drm_encoder *encoder)
 
 	DRM_DEBUG_DRIVER("Disabling DSI output\n");
 
-	if (!IS_ERR(dsi->panel)) {
+	if (dsi->panel) {
 		drm_panel_disable(dsi->panel);
 		drm_panel_unprepare(dsi->panel);
 	}
@@ -835,11 +835,13 @@ static int sun6i_dsi_attach(struct mipi_dsi_host *host,
 			    struct mipi_dsi_device *device)
 {
 	struct sun6i_dsi *dsi = host_to_sun6i_dsi(host);
+	struct drm_panel *panel = of_drm_find_panel(device->dev.of_node);
 
+	if (IS_ERR(panel))
+		return PTR_ERR(panel);
+
+	dsi->panel = panel;
 	dsi->device = device;
-	dsi->panel = of_drm_find_panel(device->dev.of_node);
-	if (IS_ERR(dsi->panel))
-		return PTR_ERR(dsi->panel);
 
 	dev_info(host->dev, "Attached device %s\n", device->name);
 
-- 
2.20.1


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[PATCH AUTOSEL 4.19 36/66] drm/stm: ltdc: check crtc state before enabling LIE

[Sasha Levin]

From: Yannick Fertre <yannick.fertre@st.com>

[ Upstream commit a6bd58c51ac43083f3977057a7ad668def55812f ]

Following investigations of a hardware bug, the LIE interrupt
can occur while the display controller is not activated.
LIE interrupt (vblank) don't have to be set if the CRTC is not
enabled.

Signed-off-by: Yannick Fertre <yannick.fertre@st.com>
Acked-by: Philippe Cornu <philippe.cornu@st.com>
Signed-off-by: Benjamin Gaignard <benjamin.gaignard@st.com>
Link: https://patchwork.freedesktop.org/patch/msgid/1579601650-7055-1-git-send-email-yannick.fertre@st.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/stm/ltdc.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/stm/ltdc.c b/drivers/gpu/drm/stm/ltdc.c
index 477d0a27b9a5d..75d108db127c8 100644
--- a/drivers/gpu/drm/stm/ltdc.c
+++ b/drivers/gpu/drm/stm/ltdc.c
@@ -612,9 +612,14 @@ static const struct drm_crtc_helper_funcs ltdc_crtc_helper_funcs = {
 static int ltdc_crtc_enable_vblank(struct drm_crtc *crtc)
 {
 	struct ltdc_device *ldev = crtc_to_ltdc(crtc);
+	struct drm_crtc_state *state = crtc->state;
 
 	DRM_DEBUG_DRIVER("\n");
-	reg_set(ldev->regs, LTDC_IER, IER_LIE);
+
+	if (state->enable)
+		reg_set(ldev->regs, LTDC_IER, IER_LIE);
+	else
+		return -EPERM;
 
 	return 0;
 }
-- 
2.20.1


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[PATCH AUTOSEL 4.19 56/66] dmaengine: stm32-dma: use reset controller only at probe time

[Sasha Levin]

From: Etienne Carriere <etienne.carriere@st.com>

[ Upstream commit 8cf1e0fc50fcc25021567bb2755580504c57c83a ]

Remove reset controller reference from device instance since it is
used only at probe time.

Signed-off-by: Etienne Carriere <etienne.carriere@st.com>
Signed-off-by: Amelie Delaunay <amelie.delaunay@st.com>
Link: https://lore.kernel.org/r/20200129153628.29329-3-amelie.delaunay@st.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/dma/stm32-dma.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/dma/stm32-dma.c b/drivers/dma/stm32-dma.c
index 4903a408fc146..e58cee8ec2410 100644
--- a/drivers/dma/stm32-dma.c
+++ b/drivers/dma/stm32-dma.c
@@ -207,7 +207,6 @@ struct stm32_dma_device {
 	struct dma_device ddev;
 	void __iomem *base;
 	struct clk *clk;
-	struct reset_control *rst;
 	bool mem2mem;
 	struct stm32_dma_chan chan[STM32_DMA_MAX_CHANNELS];
 };
@@ -1215,6 +1214,7 @@ static int stm32_dma_probe(struct platform_device *pdev)
 	struct dma_device *dd;
 	const struct of_device_id *match;
 	struct resource *res;
+	struct reset_control *rst;
 	int i, ret;
 
 	match = of_match_device(stm32_dma_of_match, &pdev->dev);
@@ -1243,11 +1243,11 @@ static int stm32_dma_probe(struct platform_device *pdev)
 	dmadev->mem2mem = of_property_read_bool(pdev->dev.of_node,
 						"st,mem2mem");
 
-	dmadev->rst = devm_reset_control_get(&pdev->dev, NULL);
-	if (!IS_ERR(dmadev->rst)) {
-		reset_control_assert(dmadev->rst);
+	rst = devm_reset_control_get(&pdev->dev, NULL);
+	if (!IS_ERR(rst)) {
+		reset_control_assert(rst);
 		udelay(2);
-		reset_control_deassert(dmadev->rst);
+		reset_control_deassert(rst);
 	}
 
 	dma_cap_set(DMA_SLAVE, dd->cap_mask);
-- 
2.20.1


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[PATCH AUTOSEL 4.19 59/66] scsi: ufs: Fix ufshcd_hold() caused scheduling while atomic

[Sasha Levin]

From: Can Guo <cang@codeaurora.org>

[ Upstream commit c63d6099a7959ecc919b2549dc6b71f53521f819 ]

The async version of ufshcd_hold(async == true), which is only called in
queuecommand path as for now, is expected to work in atomic context, thus
it should not sleep or schedule out. When it runs into the condition that
clocks are ON but link is still in hibern8 state, it should bail out
without flushing the clock ungate work.

Fixes: f2a785ac2312 ("scsi: ufshcd: Fix race between clk scaling and ungate work")
Link: https://lore.kernel.org/r/1581392451-28743-6-git-send-email-cang@codeaurora.org
Reviewed-by: Hongwu Su <hongwus@codeaurora.org>
Reviewed-by: Asutosh Das <asutoshd@codeaurora.org>
Reviewed-by: Bean Huo <beanhuo@micron.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/scsi/ufs/ufshcd.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index b3dee24917a86..d91209ba18c86 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1563,6 +1563,11 @@ int ufshcd_hold(struct ufs_hba *hba, bool async)
 		 */
 		if (ufshcd_can_hibern8_during_gating(hba) &&
 		    ufshcd_is_link_hibern8(hba)) {
+			if (async) {
+				rc = -EAGAIN;
+				hba->clk_gating.active_reqs--;
+				break;
+			}
 			spin_unlock_irqrestore(hba->host->host_lock, flags);
 			flush_work(&hba->clk_gating.ungate_work);
 			spin_lock_irqsave(hba->host->host_lock, flags);
-- 
2.20.1


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