| Message ID | 1566991129-13479-1-git-send-email-nkristam@nvidia.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | soc/tegra: fuse: Add clock error check in tegra_fuse_readl | expand |
On 28/08/2019 12:18, Nagarjuna Kristam wrote: > Tegra fuse clock handle is retrieved in tegra_fuse_probe(). > tegra_fuse_readl() is exported symbol, which can be called from drivers > at any time. tegra_fuse_readl() enables fuse clock and reads corresponding > fuse register offset. > > Calling tegra_fuse_readl() before tegra_fuse_probe(), will cause data > abort. Add DEFER_PROBE error check for fuse clock in tegra_fuse_readl(), > to avoid enabling of fuse clock, before clock is available. > > Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com> > --- > drivers/soc/tegra/fuse/fuse-tegra.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c > index 3eb44e6..21b39b7 100644 > --- a/drivers/soc/tegra/fuse/fuse-tegra.c > +++ b/drivers/soc/tegra/fuse/fuse-tegra.c > @@ -186,7 +186,7 @@ u32 __init tegra_fuse_read_early(unsigned int offset) > > int tegra_fuse_readl(unsigned long offset, u32 *value) > { > - if (!fuse->read) > + if (!fuse->read || (PTR_ERR(fuse->clk) == -EPROBE_DEFER)) > return -EPROBE_DEFER; What about the case where fuse->clk is NULL or a different error value? Jon
On 02-09-2019 16:15, Jon Hunter wrote: > > On 28/08/2019 12:18, Nagarjuna Kristam wrote: >> Tegra fuse clock handle is retrieved in tegra_fuse_probe(). >> tegra_fuse_readl() is exported symbol, which can be called from drivers >> at any time. tegra_fuse_readl() enables fuse clock and reads corresponding >> fuse register offset. >> >> Calling tegra_fuse_readl() before tegra_fuse_probe(), will cause data >> abort. Add DEFER_PROBE error check for fuse clock in tegra_fuse_readl(), >> to avoid enabling of fuse clock, before clock is available. >> >> Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com> >> --- >> drivers/soc/tegra/fuse/fuse-tegra.c | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c >> index 3eb44e6..21b39b7 100644 >> --- a/drivers/soc/tegra/fuse/fuse-tegra.c >> +++ b/drivers/soc/tegra/fuse/fuse-tegra.c >> @@ -186,7 +186,7 @@ u32 __init tegra_fuse_read_early(unsigned int offset) >> >> int tegra_fuse_readl(unsigned long offset, u32 *value) >> { >> - if (!fuse->read) >> + if (!fuse->read || (PTR_ERR(fuse->clk) == -EPROBE_DEFER)) >> return -EPROBE_DEFER; > > What about the case where fuse->clk is NULL or a different error value? > > Jon > Yes, all error checks are needed, will use IS_ERR as a separate condition for clock. Thanks, Nagarjuna
diff --git a/drivers/soc/tegra/fuse/fuse-tegra.c b/drivers/soc/tegra/fuse/fuse-tegra.c index 3eb44e6..21b39b7 100644 --- a/drivers/soc/tegra/fuse/fuse-tegra.c +++ b/drivers/soc/tegra/fuse/fuse-tegra.c @@ -186,7 +186,7 @@ u32 __init tegra_fuse_read_early(unsigned int offset) int tegra_fuse_readl(unsigned long offset, u32 *value) { - if (!fuse->read) + if (!fuse->read || (PTR_ERR(fuse->clk) == -EPROBE_DEFER)) return -EPROBE_DEFER; *value = fuse->read(fuse, offset);
Tegra fuse clock handle is retrieved in tegra_fuse_probe(). tegra_fuse_readl() is exported symbol, which can be called from drivers at any time. tegra_fuse_readl() enables fuse clock and reads corresponding fuse register offset. Calling tegra_fuse_readl() before tegra_fuse_probe(), will cause data abort. Add DEFER_PROBE error check for fuse clock in tegra_fuse_readl(), to avoid enabling of fuse clock, before clock is available. Signed-off-by: Nagarjuna Kristam <nkristam@nvidia.com> --- drivers/soc/tegra/fuse/fuse-tegra.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)