usb: renesas_usbhs: Add multiple clocks management

R-Car Gen3 needs to enable clocks of both host and peripheral.
Since [eo]hci-platform disables the reset(s) when the drivers are
removed, renesas_usbhs driver doesn't work correctly. To fix this
issue, this patch adds multiple clocks management on this
renesas_usbhs driver.

Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/usb/renesas_usbhs/common.c b/drivers/usb/renesas_usbhs/common.c
index 1d355d5..d6c39ba 100644 (file)
--- a/drivers/usb/renesas_usbhs/common.c
+++ b/drivers/usb/renesas_usbhs/common.c
@@ -5,6 +5,7 @@
  * Copyright (C) 2011 Renesas Solutions Corp.
  * Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
  */
+#include <linux/clk.h>
 #include <linux/err.h>
 #include <linux/gpio.h>
 #include <linux/io.h>
@@ -291,6 +292,79 @@ static void usbhsc_set_buswait(struct usbhs_priv *priv)
                usbhs_bset(priv, BUSWAIT, 0x000F, wait);
 }
 
+static bool usbhsc_is_multi_clks(struct usbhs_priv *priv)
+{
+       if (priv->dparam.type == USBHS_TYPE_RCAR_GEN3 ||
+           priv->dparam.type == USBHS_TYPE_RCAR_GEN3_WITH_PLL)
+               return true;
+
+       return false;
+}
+
+static int usbhsc_clk_get(struct device *dev, struct usbhs_priv *priv)
+{
+       if (!usbhsc_is_multi_clks(priv))
+               return 0;
+
+       /* The first clock should exist */
+       priv->clks[0] = of_clk_get(dev->of_node, 0);
+       if (IS_ERR(priv->clks[0]))
+               return PTR_ERR(priv->clks[0]);
+
+       /*
+        * To backward compatibility with old DT, this driver checks the return
+        * value if it's -ENOENT or not.
+        */
+       priv->clks[1] = of_clk_get(dev->of_node, 1);
+       if (PTR_ERR(priv->clks[1]) == -ENOENT)
+               priv->clks[1] = NULL;
+       else if (IS_ERR(priv->clks[1]))
+               return PTR_ERR(priv->clks[1]);
+
+       return 0;
+}
+
+static void usbhsc_clk_put(struct usbhs_priv *priv)
+{
+       int i;
+
+       if (!usbhsc_is_multi_clks(priv))
+               return;
+
+       for (i = 0; i < ARRAY_SIZE(priv->clks); i++)
+               clk_put(priv->clks[i]);
+}
+
+static int usbhsc_clk_prepare_enable(struct usbhs_priv *priv)
+{
+       int i, ret;
+
+       if (!usbhsc_is_multi_clks(priv))
+               return 0;
+
+       for (i = 0; i < ARRAY_SIZE(priv->clks); i++) {
+               ret = clk_prepare_enable(priv->clks[i]);
+               if (ret) {
+                       while (--i >= 0)
+                               clk_disable_unprepare(priv->clks[i]);
+                       return ret;
+               }
+       }
+
+       return ret;
+}
+
+static void usbhsc_clk_disable_unprepare(struct usbhs_priv *priv)
+{
+       int i;
+
+       if (!usbhsc_is_multi_clks(priv))
+               return;
+
+       for (i = 0; i < ARRAY_SIZE(priv->clks); i++)
+               clk_disable_unprepare(priv->clks[i]);
+}
+
 /*
  *             platform default param
  */
@@ -341,6 +415,10 @@ static void usbhsc_power_ctrl(struct usbhs_priv *priv, int enable)
                /* enable PM */
                pm_runtime_get_sync(dev);
 
+               /* enable clks */
+               if (usbhsc_clk_prepare_enable(priv))
+                       return;
+
                /* enable platform power */
                usbhs_platform_call(priv, power_ctrl, pdev, priv->base, enable);
 
@@ -353,6 +431,9 @@ static void usbhsc_power_ctrl(struct usbhs_priv *priv, int enable)
                /* disable platform power */
                usbhs_platform_call(priv, power_ctrl, pdev, priv->base, enable);
 
+               /* disable clks */
+               usbhsc_clk_disable_unprepare(priv);
+
                /* disable PM */
                pm_runtime_put_sync(dev);
        }
@@ -667,6 +748,10 @@ static int usbhs_probe(struct platform_device *pdev)
        if (ret)
                goto probe_fail_rst;
 
+       ret = usbhsc_clk_get(&pdev->dev, priv);
+       if (ret)
+               goto probe_fail_clks;
+
        /*
         * deviece reset here because
         * USB device might be used in boot loader.
@@ -720,6 +805,8 @@ static int usbhs_probe(struct platform_device *pdev)
        return ret;
 
 probe_end_mod_exit:
+       usbhsc_clk_put(priv);
+probe_fail_clks:
        reset_control_assert(priv->rsts);
 probe_fail_rst:
        usbhs_mod_remove(priv);
@@ -750,6 +837,7 @@ static int usbhs_remove(struct platform_device *pdev)
        pm_runtime_disable(&pdev->dev);
 
        usbhs_platform_call(priv, hardware_exit, pdev);
+       usbhsc_clk_put(priv);
        reset_control_assert(priv->rsts);
        usbhs_mod_remove(priv);
        usbhs_fifo_remove(priv);

diff --git a/drivers/usb/renesas_usbhs/common.h b/drivers/usb/renesas_usbhs/common.h
index bce7d35..555b3e7 100644 (file)
--- a/drivers/usb/renesas_usbhs/common.h
+++ b/drivers/usb/renesas_usbhs/common.h
@@ -8,6 +8,7 @@
 #ifndef RENESAS_USB_DRIVER_H
 #define RENESAS_USB_DRIVER_H
 
+#include <linux/clk.h>
 #include <linux/extcon.h>
 #include <linux/platform_device.h>
 #include <linux/reset.h>
@@ -279,6 +280,7 @@ struct usbhs_priv {
 
        struct phy *phy;
        struct reset_control *rsts;
+       struct clk *clks[2];
 };
 
 /*