[PATCH v2 0/3] ata: ahci-platform: add reset control support except for existing drivers

[PATCH v2 0/3] ata: ahci-platform: add reset control support except for existing drivers

[Kunihiko Hayashi]

Add support to get and control a list of resets for the device, and
add the flag indicating whether to use the reset. Existing SoC-dependent
drivers set 0 to this flag.

This series solves the issue of the previous patch [1] that was already
reverted [2].
[1] https://www.spinics.net/lists/linux-ide/msg55299.html
[2] https://www.spinics.net/lists/linux-ide/msg55379.html

Changes since v1:
- collect patches for each soc-dependent driver
- separate into 3 patches not to affect existing code

Kunihiko Hayashi (3):
  ata: add an extra argument to ahci_platform_get_resources()
  ata: libahci_platform: add reset control support
  ata: ahci_platform: enable to get and control reset

 .../devicetree/bindings/ata/ahci-platform.txt      |  1 +
 drivers/ata/ahci.h                                 |  1 +
 drivers/ata/ahci_brcm.c                            |  2 +-
 drivers/ata/ahci_ceva.c                            |  2 +-
 drivers/ata/ahci_da850.c                           |  2 +-
 drivers/ata/ahci_dm816.c                           |  2 +-
 drivers/ata/ahci_imx.c                             |  2 +-
 drivers/ata/ahci_mtk.c                             |  2 +-
 drivers/ata/ahci_mvebu.c                           |  2 +-
 drivers/ata/ahci_platform.c                        |  3 +-
 drivers/ata/ahci_qoriq.c                           |  2 +-
 drivers/ata/ahci_seattle.c                         |  2 +-
 drivers/ata/ahci_st.c                              |  2 +-
 drivers/ata/ahci_sunxi.c                           |  2 +-
 drivers/ata/ahci_tegra.c                           |  2 +-
 drivers/ata/ahci_xgene.c                           |  2 +-
 drivers/ata/libahci_platform.c                     | 35 ++++++++++++++++++----
 include/linux/ahci_platform.h                      |  4 ++-
 18 files changed, 49 insertions(+), 21 deletions(-)

-- 
2.7.4

[PATCH v2 1/3] ata: add an extra argument to ahci_platform_get_resources()

[Kunihiko Hayashi]

Add an extra argument to ahci_platform_get_resources(), that is
for the bitmap representing the resource to get in this function.

Currently there is no resources to be defined, so all the callers set
'0' to the argument.

Suggested-by: Hans de Goede <hdegoede@redhat.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Patrice Chotard <patrice.chotard@st.com>
Cc: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
---
 drivers/ata/ahci_brcm.c        | 2 +-
 drivers/ata/ahci_ceva.c        | 2 +-
 drivers/ata/ahci_da850.c       | 2 +-
 drivers/ata/ahci_dm816.c       | 2 +-
 drivers/ata/ahci_imx.c         | 2 +-
 drivers/ata/ahci_mtk.c         | 2 +-
 drivers/ata/ahci_mvebu.c       | 2 +-
 drivers/ata/ahci_platform.c    | 2 +-
 drivers/ata/ahci_qoriq.c       | 2 +-
 drivers/ata/ahci_seattle.c     | 2 +-
 drivers/ata/ahci_st.c          | 2 +-
 drivers/ata/ahci_sunxi.c       | 2 +-
 drivers/ata/ahci_tegra.c       | 2 +-
 drivers/ata/ahci_xgene.c       | 2 +-
 drivers/ata/libahci_platform.c | 4 +++-
 include/linux/ahci_platform.h  | 2 +-
 16 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/drivers/ata/ahci_brcm.c b/drivers/ata/ahci_brcm.c
index ea43081..f3d5577 100644
--- a/drivers/ata/ahci_brcm.c
+++ b/drivers/ata/ahci_brcm.c
@@ -425,7 +425,7 @@ static int brcm_ahci_probe(struct platform_device *pdev)
 
 	brcm_sata_phys_enable(priv);
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 	hpriv->plat_data = priv;
diff --git a/drivers/ata/ahci_ceva.c b/drivers/ata/ahci_ceva.c
index 5ecc9d4..dc78c98 100644
--- a/drivers/ata/ahci_ceva.c
+++ b/drivers/ata/ahci_ceva.c
@@ -213,7 +213,7 @@ static int ceva_ahci_probe(struct platform_device *pdev)
 
 	cevapriv->ahci_pdev = pdev;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_da850.c b/drivers/ata/ahci_da850.c
index 9b34dff..ebaa657 100644
--- a/drivers/ata/ahci_da850.c
+++ b/drivers/ata/ahci_da850.c
@@ -171,7 +171,7 @@ static int ahci_da850_probe(struct platform_device *pdev)
 	u32 mpy;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_dm816.c b/drivers/ata/ahci_dm816.c
index fbd827c..89509c3 100644
--- a/drivers/ata/ahci_dm816.c
+++ b/drivers/ata/ahci_dm816.c
@@ -148,7 +148,7 @@ static int ahci_dm816_probe(struct platform_device *pdev)
 	struct ahci_host_priv *hpriv;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_imx.c b/drivers/ata/ahci_imx.c
index 6822e2f..b00799d 100644
--- a/drivers/ata/ahci_imx.c
+++ b/drivers/ata/ahci_imx.c
@@ -1127,7 +1127,7 @@ static int imx_ahci_probe(struct platform_device *pdev)
 			return ret;
 	}
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_mtk.c b/drivers/ata/ahci_mtk.c
index 0ae6971..8bc1a26 100644
--- a/drivers/ata/ahci_mtk.c
+++ b/drivers/ata/ahci_mtk.c
@@ -142,7 +142,7 @@ static int mtk_ahci_probe(struct platform_device *pdev)
 	if (!plat)
 		return -ENOMEM;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_mvebu.c b/drivers/ata/ahci_mvebu.c
index 72d90b4..f9cb51b 100644
--- a/drivers/ata/ahci_mvebu.c
+++ b/drivers/ata/ahci_mvebu.c
@@ -158,7 +158,7 @@ static int ahci_mvebu_probe(struct platform_device *pdev)
 	const struct mbus_dram_target_info *dram;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 99f9a89..5709273 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -43,7 +43,7 @@ static int ahci_probe(struct platform_device *pdev)
 	struct ahci_host_priv *hpriv;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_qoriq.c b/drivers/ata/ahci_qoriq.c
index cfdef4d..ce59253 100644
--- a/drivers/ata/ahci_qoriq.c
+++ b/drivers/ata/ahci_qoriq.c
@@ -250,7 +250,7 @@ static int ahci_qoriq_probe(struct platform_device *pdev)
 	struct resource *res;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_seattle.c b/drivers/ata/ahci_seattle.c
index 1d31c0c..e57b6f9 100644
--- a/drivers/ata/ahci_seattle.c
+++ b/drivers/ata/ahci_seattle.c
@@ -164,7 +164,7 @@ static int ahci_seattle_probe(struct platform_device *pdev)
 	int rc;
 	struct ahci_host_priv *hpriv;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_st.c b/drivers/ata/ahci_st.c
index bc345f2..21c5c44 100644
--- a/drivers/ata/ahci_st.c
+++ b/drivers/ata/ahci_st.c
@@ -156,7 +156,7 @@ static int st_ahci_probe(struct platform_device *pdev)
 	if (!drv_data)
 		return -ENOMEM;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 	hpriv->plat_data = drv_data;
diff --git a/drivers/ata/ahci_sunxi.c b/drivers/ata/ahci_sunxi.c
index b264374..631610b 100644
--- a/drivers/ata/ahci_sunxi.c
+++ b/drivers/ata/ahci_sunxi.c
@@ -181,7 +181,7 @@ static int ahci_sunxi_probe(struct platform_device *pdev)
 	struct ahci_host_priv *hpriv;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_tegra.c b/drivers/ata/ahci_tegra.c
index 64d8484..004f260 100644
--- a/drivers/ata/ahci_tegra.c
+++ b/drivers/ata/ahci_tegra.c
@@ -494,7 +494,7 @@ static int tegra_ahci_probe(struct platform_device *pdev)
 	int ret;
 	unsigned int i;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/ahci_xgene.c b/drivers/ata/ahci_xgene.c
index ad58da7..7e157e1 100644
--- a/drivers/ata/ahci_xgene.c
+++ b/drivers/ata/ahci_xgene.c
@@ -759,7 +759,7 @@ static int xgene_ahci_probe(struct platform_device *pdev)
 					      &xgene_ahci_v2_port_info };
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev);
+	hpriv = ahci_platform_get_resources(pdev, 0);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
index 30cc8f1..6abc1cd 100644
--- a/drivers/ata/libahci_platform.c
+++ b/drivers/ata/libahci_platform.c
@@ -332,6 +332,7 @@ static int ahci_platform_get_regulator(struct ahci_host_priv *hpriv, u32 port,
 /**
  * ahci_platform_get_resources - Get platform resources
  * @pdev: platform device to get resources for
+ * @flags: bitmap representing the resource to get
  *
  * This function allocates an ahci_host_priv struct, and gets the following
  * resources, storing a reference to them inside the returned struct:
@@ -345,7 +346,8 @@ static int ahci_platform_get_regulator(struct ahci_host_priv *hpriv, u32 port,
  * RETURNS:
  * The allocated ahci_host_priv on success, otherwise an ERR_PTR value
  */
-struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev)
+struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev,
+						   unsigned int flags)
 {
 	struct device *dev = &pdev->dev;
 	struct ahci_host_priv *hpriv;
diff --git a/include/linux/ahci_platform.h b/include/linux/ahci_platform.h
index 1b0a17b..6490be1 100644
--- a/include/linux/ahci_platform.h
+++ b/include/linux/ahci_platform.h
@@ -30,7 +30,7 @@ void ahci_platform_disable_regulators(struct ahci_host_priv *hpriv);
 int ahci_platform_enable_resources(struct ahci_host_priv *hpriv);
 void ahci_platform_disable_resources(struct ahci_host_priv *hpriv);
 struct ahci_host_priv *ahci_platform_get_resources(
-	struct platform_device *pdev);
+	struct platform_device *pdev, unsigned int flags);
 int ahci_platform_init_host(struct platform_device *pdev,
 			    struct ahci_host_priv *hpriv,
 			    const struct ata_port_info *pi_template,
-- 
2.7.4

[PATCH v2 2/3] ata: libahci_platform: add reset control support

[Kunihiko Hayashi]

Add support to get and control a list of resets for the device
as optional and shared. These resets must be kept de-asserted until
the device is enabled.

This is specified as shared because some SoCs like UniPhier series
have common reset controls with all ahci controller instances.

However, according to Thierry's view,
https://www.spinics.net/lists/linux-ide/msg55357.html
some hardware-specific drivers already use their own resets,
and the common reset make a path to occur double controls of resets.

The ahci_platform_get_resources() can get and control the reset
only when the second argument includes AHCI_PLATFORM_GET_RESETS bit.

Suggested-by: Hans de Goede <hdegoede@redhat.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
---
 .../devicetree/bindings/ata/ahci-platform.txt      |  1 +
 drivers/ata/ahci.h                                 |  1 +
 drivers/ata/libahci_platform.c                     | 31 ++++++++++++++++++----
 include/linux/ahci_platform.h                      |  2 ++
 4 files changed, 30 insertions(+), 5 deletions(-)

diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
index c760ecb..f4006d3 100644
--- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
+++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
@@ -30,6 +30,7 @@ compatible:
 Optional properties:
 - dma-coherent      : Present if dma operations are coherent
 - clocks            : a list of phandle + clock specifier pairs
+- resets            : a list of phandle + reset specifier pairs
 - target-supply     : regulator for SATA target power
 - phys              : reference to the SATA PHY node
 - phy-names         : must be "sata-phy"
diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 1609eba..6a1515f 100644
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -350,6 +350,7 @@ struct ahci_host_priv {
 	u32			em_msg_type;	/* EM message type */
 	bool			got_runtime_pm; /* Did we do pm_runtime_get? */
 	struct clk		*clks[AHCI_MAX_CLKS]; /* Optional */
+	struct reset_control	*rsts;		/* Optional */
 	struct regulator	**target_pwrs;	/* Optional */
 	/*
 	 * If platform uses PHYs. There is a 1:1 relation between the port number and
diff --git a/drivers/ata/libahci_platform.c b/drivers/ata/libahci_platform.c
index 6abc1cd..6817143 100644
--- a/drivers/ata/libahci_platform.c
+++ b/drivers/ata/libahci_platform.c
@@ -25,6 +25,7 @@
 #include <linux/phy/phy.h>
 #include <linux/pm_runtime.h>
 #include <linux/of_platform.h>
+#include <linux/reset.h>
 #include "ahci.h"
 
 static void ahci_host_stop(struct ata_host *host);
@@ -195,7 +196,8 @@ EXPORT_SYMBOL_GPL(ahci_platform_disable_regulators);
  * following order:
  * 1) Regulator
  * 2) Clocks (through ahci_platform_enable_clks)
- * 3) Phys
+ * 3) Resets
+ * 4) Phys
  *
  * If resource enabling fails at any point the previous enabled resources
  * are disabled in reverse order.
@@ -215,12 +217,19 @@ int ahci_platform_enable_resources(struct ahci_host_priv *hpriv)
 	if (rc)
 		goto disable_regulator;
 
-	rc = ahci_platform_enable_phys(hpriv);
+	rc = reset_control_deassert(hpriv->rsts);
 	if (rc)
 		goto disable_clks;
 
+	rc = ahci_platform_enable_phys(hpriv);
+	if (rc)
+		goto disable_resets;
+
 	return 0;
 
+disable_resets:
+	reset_control_assert(hpriv->rsts);
+
 disable_clks:
 	ahci_platform_disable_clks(hpriv);
 
@@ -238,13 +247,16 @@ EXPORT_SYMBOL_GPL(ahci_platform_enable_resources);
  * This function disables all ahci_platform managed resources in the
  * following order:
  * 1) Phys
- * 2) Clocks (through ahci_platform_disable_clks)
- * 3) Regulator
+ * 2) Resets
+ * 3) Clocks (through ahci_platform_disable_clks)
+ * 4) Regulator
  */
 void ahci_platform_disable_resources(struct ahci_host_priv *hpriv)
 {
 	ahci_platform_disable_phys(hpriv);
 
+	reset_control_assert(hpriv->rsts);
+
 	ahci_platform_disable_clks(hpriv);
 
 	ahci_platform_disable_regulators(hpriv);
@@ -341,7 +353,8 @@ static int ahci_platform_get_regulator(struct ahci_host_priv *hpriv, u32 port,
  * 2) regulator for controlling the targets power (optional)
  * 3) 0 - AHCI_MAX_CLKS clocks, as specified in the devs devicetree node,
  *    or for non devicetree enabled platforms a single clock
- * 4) phys (optional)
+ * 4) resets, if flags has AHCI_PLATFORM_GET_RESETS (optional)
+ * 5) phys (optional)
  *
  * RETURNS:
  * The allocated ahci_host_priv on success, otherwise an ERR_PTR value
@@ -395,6 +408,14 @@ struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev,
 		hpriv->clks[i] = clk;
 	}
 
+	if (flags & AHCI_PLATFORM_GET_RESETS) {
+		hpriv->rsts = devm_reset_control_array_get_optional_shared(dev);
+		if (IS_ERR(hpriv->rsts)) {
+			rc = PTR_ERR(hpriv->rsts);
+			goto err_out;
+		}
+	}
+
 	hpriv->nports = child_nodes = of_get_child_count(dev->of_node);
 
 	/*
diff --git a/include/linux/ahci_platform.h b/include/linux/ahci_platform.h
index 6490be1..eaedca5f 100644
--- a/include/linux/ahci_platform.h
+++ b/include/linux/ahci_platform.h
@@ -43,4 +43,6 @@ int ahci_platform_resume_host(struct device *dev);
 int ahci_platform_suspend(struct device *dev);
 int ahci_platform_resume(struct device *dev);
 
+#define AHCI_PLATFORM_GET_RESETS	0x01
+
 #endif /* _AHCI_PLATFORM_H */
-- 
2.7.4

[PATCH v2 3/3] ata: ahci_platform: enable to get and control reset

[Kunihiko Hayashi]

Unlike SoC-specific driver, generic ahci_platform driver doesn't
have any chances to control resets.

This adds AHCI_PLATFORM_GET_RESETS to ahci_platform_get_resources()
on the generic driver to enable reset control support.

Suggested-by: Hans de Goede <hdegoede@redhat.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
---
 drivers/ata/ahci_platform.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index 5709273..ddd9308 100644
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -43,7 +43,8 @@ static int ahci_probe(struct platform_device *pdev)
 	struct ahci_host_priv *hpriv;
 	int rc;
 
-	hpriv = ahci_platform_get_resources(pdev, 0);
+	hpriv = ahci_platform_get_resources(pdev,
+					    AHCI_PLATFORM_GET_RESETS);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);
 
-- 
2.7.4

Re: [PATCH v2 0/3] ata: ahci-platform: add reset control support except for existing drivers

[Hans de Goede]

Hi,

On 22-08-18 14:13, Kunihiko Hayashi wrote:
> Add support to get and control a list of resets for the device, and
> add the flag indicating whether to use the reset. Existing SoC-dependent
> drivers set 0 to this flag.
> 
> This series solves the issue of the previous patch [1] that was already
> reverted [2].
> [1] https://www.spinics.net/lists/linux-ide/msg55299.html
> [2] https://www.spinics.net/lists/linux-ide/msg55379.html
> 
> Changes since v1:
> - collect patches for each soc-dependent driver
> - separate into 3 patches not to affect existing code

Thanks, series looks good to me now:

Reviewed-by: Hans de Goede <hdegoede@redhat.com>

Regards,

Hans


> 
> Kunihiko Hayashi (3):
>    ata: add an extra argument to ahci_platform_get_resources()
>    ata: libahci_platform: add reset control support
>    ata: ahci_platform: enable to get and control reset
> 
>   .../devicetree/bindings/ata/ahci-platform.txt      |  1 +
>   drivers/ata/ahci.h                                 |  1 +
>   drivers/ata/ahci_brcm.c                            |  2 +-
>   drivers/ata/ahci_ceva.c                            |  2 +-
>   drivers/ata/ahci_da850.c                           |  2 +-
>   drivers/ata/ahci_dm816.c                           |  2 +-
>   drivers/ata/ahci_imx.c                             |  2 +-
>   drivers/ata/ahci_mtk.c                             |  2 +-
>   drivers/ata/ahci_mvebu.c                           |  2 +-
>   drivers/ata/ahci_platform.c                        |  3 +-
>   drivers/ata/ahci_qoriq.c                           |  2 +-
>   drivers/ata/ahci_seattle.c                         |  2 +-
>   drivers/ata/ahci_st.c                              |  2 +-
>   drivers/ata/ahci_sunxi.c                           |  2 +-
>   drivers/ata/ahci_tegra.c                           |  2 +-
>   drivers/ata/ahci_xgene.c                           |  2 +-
>   drivers/ata/libahci_platform.c                     | 35 ++++++++++++++++++----
>   include/linux/ahci_platform.h                      |  4 ++-
>   18 files changed, 49 insertions(+), 21 deletions(-)
> 

Re: [PATCH v2 0/3] ata: ahci-platform: add reset control support except for existing drivers

[Tejun Heo]

On Wed, Aug 22, 2018 at 09:13:00PM +0900, Kunihiko Hayashi wrote:
> Add support to get and control a list of resets for the device, and
> add the flag indicating whether to use the reset. Existing SoC-dependent
> drivers set 0 to this flag.

Applied to libata/for-4.19.

Thanks.

-- 
tejun

Re: [PATCH v2 2/3] ata: libahci_platform: add reset control support

[Rob Herring]

On Wed, Aug 22, 2018 at 09:13:02PM +0900, Kunihiko Hayashi wrote:
> Add support to get and control a list of resets for the device
> as optional and shared. These resets must be kept de-asserted until
> the device is enabled.
> 
> This is specified as shared because some SoCs like UniPhier series
> have common reset controls with all ahci controller instances.
> 
> However, according to Thierry's view,
> https://www.spinics.net/lists/linux-ide/msg55357.html
> some hardware-specific drivers already use their own resets,
> and the common reset make a path to occur double controls of resets.
> 
> The ahci_platform_get_resources() can get and control the reset
> only when the second argument includes AHCI_PLATFORM_GET_RESETS bit.
> 
> Suggested-by: Hans de Goede <hdegoede@redhat.com>
> Cc: Thierry Reding <thierry.reding@gmail.com>
> Signed-off-by: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> ---
>  .../devicetree/bindings/ata/ahci-platform.txt      |  1 +

Acked-by: Rob Herring <robh@kernel.org>

>  drivers/ata/ahci.h                                 |  1 +
>  drivers/ata/libahci_platform.c                     | 31 ++++++++++++++++++----
>  include/linux/ahci_platform.h                      |  2 ++
>  4 files changed, 30 insertions(+), 5 deletions(-)