| Message ID | 1306765534-20103-2-git-send-email-balajitk@ti.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
* Balaji T K <balajitk@ti.com> [110530 07:23]: > 4 micro seconds is not enough for PBIAS if MMC regulator is > enabled from MMC regulator OFF. > Increase the delay for PBIAS to stabilize. > Wait for PBIAS and timeout if not. > > Resolves MMC/SD failure on OMAP4 > "Pbias Voltage is not same as LDO" > > Signed-off-by: Balaji T K <balajitk@ti.com> > --- > arch/arm/mach-omap2/hsmmc.c | 13 ++++++++++--- > 1 files changed, 10 insertions(+), 3 deletions(-) > > diff --git a/arch/arm/mach-omap2/hsmmc.c b/arch/arm/mach-omap2/hsmmc.c > index b2f30be..3f8dc16 100644 > --- a/arch/arm/mach-omap2/hsmmc.c > +++ b/arch/arm/mach-omap2/hsmmc.c > @@ -145,6 +145,7 @@ static void omap4_hsmmc1_after_set_reg(struct device *dev, int slot, > int power_on, int vdd) > { > u32 reg; > + unsigned long timeout; > > if (power_on) { > reg = omap4_ctrl_pad_readl(control_pbias_offset); > @@ -157,9 +158,15 @@ static void omap4_hsmmc1_after_set_reg(struct device *dev, int slot, > OMAP4_MMC1_PWRDNZ_MASK | > OMAP4_USBC1_ICUSB_PWRDNZ_MASK); > omap4_ctrl_pad_writel(reg, control_pbias_offset); > - /* 4 microsec delay for comparator to generate an error*/ > - udelay(4); > - reg = omap4_ctrl_pad_readl(control_pbias_offset); > + > + timeout = jiffies + msecs_to_jiffies(5); > + do { > + reg = omap4_ctrl_pad_readl(control_pbias_offset); > + if (!(reg & OMAP4_MMC1_PBIASLITE_VMODE_ERROR_MASK)) > + break; > + udelay(100); > + } while (!time_after(jiffies, timeout)); > + > if (reg & OMAP4_MMC1_PBIASLITE_VMODE_ERROR_MASK) { > pr_err("Pbias Voltage is not same as LDO\n"); > /* Caution : On VMODE_ERROR Power Down MMC IO */ Actually, can you check if you can use usleep_range here as recommended by checkpatch.pl? Tony
On Wed, Jun 1, 2011 at 1:11 PM, Tony Lindgren <tony@atomide.com> wrote: > * Balaji T K <balajitk@ti.com> [110530 07:23]: >> 4 micro seconds is not enough for PBIAS if MMC regulator is >> enabled from MMC regulator OFF. >> Increase the delay for PBIAS to stabilize. >> Wait for PBIAS and timeout if not. >> >> Resolves MMC/SD failure on OMAP4 >> "Pbias Voltage is not same as LDO" >> >> Signed-off-by: Balaji T K <balajitk@ti.com> >> --- >> arch/arm/mach-omap2/hsmmc.c | 13 ++++++++++--- >> 1 files changed, 10 insertions(+), 3 deletions(-) >> >> diff --git a/arch/arm/mach-omap2/hsmmc.c b/arch/arm/mach-omap2/hsmmc.c >> index b2f30be..3f8dc16 100644 >> --- a/arch/arm/mach-omap2/hsmmc.c >> +++ b/arch/arm/mach-omap2/hsmmc.c >> @@ -145,6 +145,7 @@ static void omap4_hsmmc1_after_set_reg(struct device *dev, int slot, >> int power_on, int vdd) >> { >> u32 reg; >> + unsigned long timeout; >> >> if (power_on) { >> reg = omap4_ctrl_pad_readl(control_pbias_offset); >> @@ -157,9 +158,15 @@ static void omap4_hsmmc1_after_set_reg(struct device *dev, int slot, >> OMAP4_MMC1_PWRDNZ_MASK | >> OMAP4_USBC1_ICUSB_PWRDNZ_MASK); >> omap4_ctrl_pad_writel(reg, control_pbias_offset); >> - /* 4 microsec delay for comparator to generate an error*/ >> - udelay(4); >> - reg = omap4_ctrl_pad_readl(control_pbias_offset); >> + >> + timeout = jiffies + msecs_to_jiffies(5); >> + do { >> + reg = omap4_ctrl_pad_readl(control_pbias_offset); >> + if (!(reg & OMAP4_MMC1_PBIASLITE_VMODE_ERROR_MASK)) >> + break; >> + udelay(100); >> + } while (!time_after(jiffies, timeout)); >> + >> if (reg & OMAP4_MMC1_PBIASLITE_VMODE_ERROR_MASK) { >> pr_err("Pbias Voltage is not same as LDO\n"); >> /* Caution : On VMODE_ERROR Power Down MMC IO */ > > Actually, can you check if you can use usleep_range here as recommended > by checkpatch.pl? sure, fixing it in v2 > > Tony >
diff --git a/arch/arm/mach-omap2/hsmmc.c b/arch/arm/mach-omap2/hsmmc.c index b2f30be..3f8dc16 100644 --- a/arch/arm/mach-omap2/hsmmc.c +++ b/arch/arm/mach-omap2/hsmmc.c @@ -145,6 +145,7 @@ static void omap4_hsmmc1_after_set_reg(struct device *dev, int slot, int power_on, int vdd) { u32 reg; + unsigned long timeout; if (power_on) { reg = omap4_ctrl_pad_readl(control_pbias_offset); @@ -157,9 +158,15 @@ static void omap4_hsmmc1_after_set_reg(struct device *dev, int slot, OMAP4_MMC1_PWRDNZ_MASK | OMAP4_USBC1_ICUSB_PWRDNZ_MASK); omap4_ctrl_pad_writel(reg, control_pbias_offset); - /* 4 microsec delay for comparator to generate an error*/ - udelay(4); - reg = omap4_ctrl_pad_readl(control_pbias_offset); + + timeout = jiffies + msecs_to_jiffies(5); + do { + reg = omap4_ctrl_pad_readl(control_pbias_offset); + if (!(reg & OMAP4_MMC1_PBIASLITE_VMODE_ERROR_MASK)) + break; + udelay(100); + } while (!time_after(jiffies, timeout)); + if (reg & OMAP4_MMC1_PBIASLITE_VMODE_ERROR_MASK) { pr_err("Pbias Voltage is not same as LDO\n"); /* Caution : On VMODE_ERROR Power Down MMC IO */
4 micro seconds is not enough for PBIAS if MMC regulator is enabled from MMC regulator OFF. Increase the delay for PBIAS to stabilize. Wait for PBIAS and timeout if not. Resolves MMC/SD failure on OMAP4 "Pbias Voltage is not same as LDO" Signed-off-by: Balaji T K <balajitk@ti.com> --- arch/arm/mach-omap2/hsmmc.c | 13 ++++++++++--- 1 files changed, 10 insertions(+), 3 deletions(-)