| Message ID | 1480612342-23614-1-git-send-email-abailon@baylibre.com |
|---|---|
| State | New |
| Headers | show |
On 12/01/2016 11:12 AM, Alexandre Bailon wrote: > Everytime the usb20 phy is enabled, there is a Every time is two words > "sleeping function called from invalid context" BUG. > > clk_enable() from arch/arm/mach-davinci/clock.c uses spin_lock_irqsave() > before to invoke the callback usb20_phy_clk_enable(). > usb20_phy_clk_enable() uses clk_get() and clk_enable_prepapre() > which may sleep. > Move clk_get() to da8xx_register_usb20_phy_clk() and > replace clk_prepare_enable() by clk_enable(). > > Signed-off-by: Alexandre Bailon <abailon@baylibre.com> > --- > arch/arm/mach-davinci/usb-da8xx.c | 23 ++++++++++++----------- > 1 file changed, 12 insertions(+), 11 deletions(-) > > diff --git a/arch/arm/mach-davinci/usb-da8xx.c b/arch/arm/mach-davinci/usb-da8xx.c > index b010e5f..bfb55b9 100644 > --- a/arch/arm/mach-davinci/usb-da8xx.c > +++ b/arch/arm/mach-davinci/usb-da8xx.c > @@ -156,23 +156,18 @@ int __init da8xx_register_usb_refclkin(int rate) > return 0; > } > > +static struct clk *usb20_clk; Not a serious issue, but I would rather have the global variable declared at the beginning of the file to make it more obvious there is a global variable. > + > static void usb20_phy_clk_enable(struct clk *clk) > { > - struct clk *usb20_clk; > int err; > u32 val; > u32 timeout = 500000; /* 500 msec */ > > val = readl(DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP2_REG)); > > - usb20_clk = clk_get(&da8xx_usb20_dev.dev, "usb20"); > - if (IS_ERR(usb20_clk)) { > - pr_err("could not get usb20 clk: %ld\n", PTR_ERR(usb20_clk)); > - return; > - } > - > /* The USB 2.O PLL requires that the USB 2.O PSC is enabled as well. */ > - err = clk_prepare_enable(usb20_clk); > + err = clk_enable(usb20_clk); > if (err) { > pr_err("failed to enable usb20 clk: %d\n", err); > clk_put(usb20_clk); > @@ -197,8 +192,7 @@ static void usb20_phy_clk_enable(struct clk *clk) > > pr_err("Timeout waiting for USB 2.0 PHY clock good\n"); > done: > - clk_disable_unprepare(usb20_clk); > - clk_put(usb20_clk); > + clk_disable(usb20_clk); > } > > static void usb20_phy_clk_disable(struct clk *clk) > @@ -287,9 +281,16 @@ int __init da8xx_register_usb20_phy_clk(bool use_usb_refclkin) > struct clk *parent; > int ret = 0; No longer need to initialize ret here. > > + usb20_clk = clk_get(&da8xx_usb20_dev.dev, "usb20"); > + ret = PTR_ERR_OR_ZERO(usb20_clk); > + if (ret) > + return ret; > + > parent = clk_get(NULL, use_usb_refclkin ? "usb_refclkin" : "pll0_aux"); > - if (IS_ERR(parent)) > + if (IS_ERR(parent)) { why not use ret = PTR_ERR_OR_ZERO(parent) pattern here too? > + clk_put(usb20_clk); The global usb20_clk is no longer valid after this. Should we set it to NULL here? > return PTR_ERR(parent); > + } > > usb20_phy_clk.parent = parent; > ret = clk_register(&usb20_phy_clk); > _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
On Thursday 01 December 2016 11:17 PM, David Lechner wrote: > >> + clk_put(usb20_clk); > > The global usb20_clk is no longer valid after this. Should we set it to > NULL here? No need of this. Also, NULL is valid clock handle. Thanks, Sekhar _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
diff --git a/arch/arm/mach-davinci/usb-da8xx.c b/arch/arm/mach-davinci/usb-da8xx.c index b010e5f..bfb55b9 100644 --- a/arch/arm/mach-davinci/usb-da8xx.c +++ b/arch/arm/mach-davinci/usb-da8xx.c @@ -156,23 +156,18 @@ int __init da8xx_register_usb_refclkin(int rate) return 0; } +static struct clk *usb20_clk; + static void usb20_phy_clk_enable(struct clk *clk) { - struct clk *usb20_clk; int err; u32 val; u32 timeout = 500000; /* 500 msec */ val = readl(DA8XX_SYSCFG0_VIRT(DA8XX_CFGCHIP2_REG)); - usb20_clk = clk_get(&da8xx_usb20_dev.dev, "usb20"); - if (IS_ERR(usb20_clk)) { - pr_err("could not get usb20 clk: %ld\n", PTR_ERR(usb20_clk)); - return; - } - /* The USB 2.O PLL requires that the USB 2.O PSC is enabled as well. */ - err = clk_prepare_enable(usb20_clk); + err = clk_enable(usb20_clk); if (err) { pr_err("failed to enable usb20 clk: %d\n", err); clk_put(usb20_clk); @@ -197,8 +192,7 @@ static void usb20_phy_clk_enable(struct clk *clk) pr_err("Timeout waiting for USB 2.0 PHY clock good\n"); done: - clk_disable_unprepare(usb20_clk); - clk_put(usb20_clk); + clk_disable(usb20_clk); } static void usb20_phy_clk_disable(struct clk *clk) @@ -287,9 +281,16 @@ int __init da8xx_register_usb20_phy_clk(bool use_usb_refclkin) struct clk *parent; int ret = 0; + usb20_clk = clk_get(&da8xx_usb20_dev.dev, "usb20"); + ret = PTR_ERR_OR_ZERO(usb20_clk); + if (ret) + return ret; + parent = clk_get(NULL, use_usb_refclkin ? "usb_refclkin" : "pll0_aux"); - if (IS_ERR(parent)) + if (IS_ERR(parent)) { + clk_put(usb20_clk); return PTR_ERR(parent); + } usb20_phy_clk.parent = parent; ret = clk_register(&usb20_phy_clk);
Everytime the usb20 phy is enabled, there is a "sleeping function called from invalid context" BUG. clk_enable() from arch/arm/mach-davinci/clock.c uses spin_lock_irqsave() before to invoke the callback usb20_phy_clk_enable(). usb20_phy_clk_enable() uses clk_get() and clk_enable_prepapre() which may sleep. Move clk_get() to da8xx_register_usb20_phy_clk() and replace clk_prepare_enable() by clk_enable(). Signed-off-by: Alexandre Bailon <abailon@baylibre.com> --- arch/arm/mach-davinci/usb-da8xx.c | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) -- 2.7.3 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel