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Message-Id: <1384964989-28760-1-git-send-email-julien.delacou@st.com>
Date: Wed, 20 Nov 2013 17:29:49 +0100
From: Julien DELACOU <julien.delacou@...com>
To: Paul Zimmerman <paulz@...opsys.com>,
Matthijs Kooijman <matthijs@...in.nl>,
Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
Grant Likely <grant.likely@...aro.org>
Cc: linux-kernel@...r.kernel.org, linux-usb@...r.kernel.org,
devel@...verdev.osuosl.org, Julien Delacou <julien.delacou@...com>
Subject: [PATCH] staging: dwc2: add check on dwc2_core_reset return
If the GRSTCTL_CSFTRST self-clearing bit never comes
back to 0 for any reason, the controller is under reset
state and cannot be used. It's preferable to abort
initialization in such case.
Signed-off-by: Julien Delacou <julien.delacou@...com>
---
drivers/staging/dwc2/core.c | 58 +++++++++++++++++++++++++++++++++----------
1 file changed, 45 insertions(+), 13 deletions(-)
diff --git a/drivers/staging/dwc2/core.c b/drivers/staging/dwc2/core.c
index 27e1964..ecce1ef 100644
--- a/drivers/staging/dwc2/core.c
+++ b/drivers/staging/dwc2/core.c
@@ -116,7 +116,7 @@ static void dwc2_init_fs_ls_pclk_sel(struct dwc2_hsotg *hsotg)
* Do core a soft reset of the core. Be careful with this because it
* resets all the internal state machines of the core.
*/
-static void dwc2_core_reset(struct dwc2_hsotg *hsotg)
+static int dwc2_core_reset(struct dwc2_hsotg *hsotg)
{
u32 greset;
int count = 0;
@@ -131,7 +131,7 @@ static void dwc2_core_reset(struct dwc2_hsotg *hsotg)
dev_warn(hsotg->dev,
"%s() HANG! AHB Idle GRSTCTL=%0x\n",
__func__, greset);
- return;
+ return -EBUSY;
}
} while (!(greset & GRSTCTL_AHBIDLE));
@@ -146,7 +146,7 @@ static void dwc2_core_reset(struct dwc2_hsotg *hsotg)
dev_warn(hsotg->dev,
"%s() HANG! Soft Reset GRSTCTL=%0x\n",
__func__, greset);
- break;
+ return -EBUSY;
}
} while (greset & GRSTCTL_CSFTRST);
@@ -155,11 +155,14 @@ static void dwc2_core_reset(struct dwc2_hsotg *hsotg)
* not stay in host mode after a connector ID change!
*/
usleep_range(150000, 200000);
+
+ return 0;
}
-static void dwc2_fs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
+static int dwc2_fs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
{
u32 usbcfg, i2cctl;
+ int retval = 0;
/*
* core_init() is now called on every switch so only call the
@@ -172,7 +175,12 @@ static void dwc2_fs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
writel(usbcfg, hsotg->regs + GUSBCFG);
/* Reset after a PHY select */
- dwc2_core_reset(hsotg);
+ retval = dwc2_core_reset(hsotg);
+ if (retval) {
+ dev_err(hsotg->dev, "%s() Reset failed, aborting",
+ __func__);
+ return retval;
+ }
}
/*
@@ -200,14 +208,17 @@ static void dwc2_fs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
i2cctl |= GI2CCTL_I2CEN;
writel(i2cctl, hsotg->regs + GI2CCTL);
}
+
+ return retval;
}
-static void dwc2_hs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
+static int dwc2_hs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
{
u32 usbcfg;
+ int retval = 0;
if (!select_phy)
- return;
+ return -ENODEV;
usbcfg = readl(hsotg->regs + GUSBCFG);
@@ -240,20 +251,32 @@ static void dwc2_hs_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
writel(usbcfg, hsotg->regs + GUSBCFG);
/* Reset after setting the PHY parameters */
- dwc2_core_reset(hsotg);
+ retval = dwc2_core_reset(hsotg);
+ if (retval) {
+ dev_err(hsotg->dev, "%s() Reset failed, aborting",
+ __func__);
+ return retval;
+ }
+
+ return retval;
}
-static void dwc2_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
+static int dwc2_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
{
u32 usbcfg;
+ int retval = 0;
if (hsotg->core_params->speed == DWC2_SPEED_PARAM_FULL &&
hsotg->core_params->phy_type == DWC2_PHY_TYPE_PARAM_FS) {
/* If FS mode with FS PHY */
- dwc2_fs_phy_init(hsotg, select_phy);
+ retval = dwc2_fs_phy_init(hsotg, select_phy);
+ if (retval)
+ return retval;
} else {
/* High speed PHY */
- dwc2_hs_phy_init(hsotg, select_phy);
+ retval = dwc2_hs_phy_init(hsotg, select_phy);
+ if (retval)
+ return retval;
}
if (hsotg->hw_params.hs_phy_type == GHWCFG2_HS_PHY_TYPE_ULPI &&
@@ -270,6 +293,8 @@ static void dwc2_phy_init(struct dwc2_hsotg *hsotg, bool select_phy)
usbcfg &= ~GUSBCFG_ULPI_CLK_SUSP_M;
writel(usbcfg, hsotg->regs + GUSBCFG);
}
+
+ return retval;
}
static int dwc2_gahbcfg_init(struct dwc2_hsotg *hsotg)
@@ -421,12 +446,19 @@ int dwc2_core_init(struct dwc2_hsotg *hsotg, bool select_phy, int irq)
writel(usbcfg, hsotg->regs + GUSBCFG);
/* Reset the Controller */
- dwc2_core_reset(hsotg);
+ retval = dwc2_core_reset(hsotg);
+ if (retval) {
+ dev_err(hsotg->dev, "%s(): Reset failed, aborting\n",
+ __func__);
+ return retval;
+ }
/*
* This needs to happen in FS mode before any other programming occurs
*/
- dwc2_phy_init(hsotg, select_phy);
+ retval = dwc2_phy_init(hsotg, select_phy);
+ if (retval)
+ return retval;
/* Program the GAHBCFG Register */
retval = dwc2_gahbcfg_init(hsotg);
--
1.7.9.5
--
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