[cip-dev] [PATCH 4.19.y 06/17] usb: renesas_usbhs: Add multiple clocks management

Fabrizio Castro
2019-04-24T17:20:29Z

From: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>

commit 3df0e240caba641e0d70640e3baf34d34c105176 upstream.

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>
Signed-off-by: Fabrizio Castro <fabrizio.castro@bp.renesas.com>
---
drivers/usb/renesas_usbhs/common.c | 88 ++++++++++++++++++++++++++++++++++++++
drivers/usb/renesas_usbhs/common.h | 2 +
2 files changed, 90 insertions(+)

diff --git a/drivers/usb/renesas_usbhs/common.c b/drivers/usb/renesas_usbhs/common.c
index 0601b14..33088b9 100644
--- 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);
}
@@ -671,6 +752,10 @@ 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.
@@ -724,6 +809,8 @@ 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);
@@ -754,6 +841,7 @@ 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..555b3e78 100644
--- 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];
};

/*
--
2.7.4