lkml.org 
[lkml]   [2018]   [Mar]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH] ata: ahci-platform: add reset control support
    Date
    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.

    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 | 24 +++++++++++++++++++---
    3 files changed, 23 insertions(+), 3 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 749fd94..47ec77a2 100644
    --- a/drivers/ata/ahci.h
    +++ b/drivers/ata/ahci.h
    @@ -347,6 +347,7 @@ 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 341d0ef..3130db9 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);

    @@ -239,12 +248,15 @@ EXPORT_SYMBOL_GPL(ahci_platform_enable_resources);
    * following order:
    * 1) Phys
    * 2) Clocks (through ahci_platform_disable_clks)
    - * 3) Regulator
    + * 3) Resets
    + * 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);
    @@ -393,6 +405,12 @@ struct ahci_host_priv *ahci_platform_get_resources(struct platform_device *pdev)
    hpriv->clks[i] = clk;
    }

    + 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);

    /*
    --
    2.7.4
    \
     
     \ /
      Last update: 2018-03-23 02:31    [W:3.406 / U:0.064 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site