| Message ID | 20201111120605.50881-1-andriy.shevchenko@linux.intel.com |
|---|---|
| State | Accepted |
| Commit | 0fa86fc2e28227f1e64f13867e73cf864c6d25ad |
| Headers | show |
| Series | [v1] pinctrl: merrifield: Set default bias in case no particular value given | expand |
On Wed, Nov 11, 2020 at 02:06:05PM +0200, Andy Shevchenko wrote: > When GPIO library asks pin control to set the bias, it doesn't pass > any value of it and argument is considered boolean (and this is true > for ACPI GpioIo() / GpioInt() resources, by the way). Thus, individual > drivers must behave well, when they got the resistance value of 1 Ohm, > i.e. transforming it to sane default. > > In case of Intel Merrifield pin control hardware the 20 kOhm sounds plausible > because it gives a good trade off between weakness and minimization of leakage > current (will be only 50 uA with the above choice). > > Fixes: 4e80c8f50574 ("pinctrl: intel: Add Intel Merrifield pin controller support") > Depends-on: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback for GPIO chips") > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
On Thu, Nov 12, 2020 at 10:06:50AM +0200, Mika Westerberg wrote: > On Wed, Nov 11, 2020 at 02:06:05PM +0200, Andy Shevchenko wrote: > > When GPIO library asks pin control to set the bias, it doesn't pass > > any value of it and argument is considered boolean (and this is true > > for ACPI GpioIo() / GpioInt() resources, by the way). Thus, individual > > drivers must behave well, when they got the resistance value of 1 Ohm, > > i.e. transforming it to sane default. > > > > In case of Intel Merrifield pin control hardware the 20 kOhm sounds plausible > > because it gives a good trade off between weakness and minimization of leakage > > current (will be only 50 uA with the above choice). > > > > Fixes: 4e80c8f50574 ("pinctrl: intel: Add Intel Merrifield pin controller support") > > Depends-on: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback for GPIO chips") > > Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> > > Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> Pushed to my review and testing queue, thanks! -- With Best Regards, Andy Shevchenko
diff --git a/drivers/pinctrl/intel/pinctrl-merrifield.c b/drivers/pinctrl/intel/pinctrl-merrifield.c index e4ff8da1b894..3ae141e0b421 100644 --- a/drivers/pinctrl/intel/pinctrl-merrifield.c +++ b/drivers/pinctrl/intel/pinctrl-merrifield.c @@ -745,6 +745,10 @@ static int mrfld_config_set_pin(struct mrfld_pinctrl *mp, unsigned int pin, mask |= BUFCFG_Px_EN_MASK | BUFCFG_PUPD_VAL_MASK; bits |= BUFCFG_PU_EN; + /* Set default strength value in case none is given */ + if (arg == 1) + arg = 20000; + switch (arg) { case 50000: bits |= BUFCFG_PUPD_VAL_50K << BUFCFG_PUPD_VAL_SHIFT; @@ -765,6 +769,10 @@ static int mrfld_config_set_pin(struct mrfld_pinctrl *mp, unsigned int pin, mask |= BUFCFG_Px_EN_MASK | BUFCFG_PUPD_VAL_MASK; bits |= BUFCFG_PD_EN; + /* Set default strength value in case none is given */ + if (arg == 1) + arg = 20000; + switch (arg) { case 50000: bits |= BUFCFG_PUPD_VAL_50K << BUFCFG_PUPD_VAL_SHIFT;
When GPIO library asks pin control to set the bias, it doesn't pass any value of it and argument is considered boolean (and this is true for ACPI GpioIo() / GpioInt() resources, by the way). Thus, individual drivers must behave well, when they got the resistance value of 1 Ohm, i.e. transforming it to sane default. In case of Intel Merrifield pin control hardware the 20 kOhm sounds plausible because it gives a good trade off between weakness and minimization of leakage current (will be only 50 uA with the above choice). Fixes: 4e80c8f50574 ("pinctrl: intel: Add Intel Merrifield pin controller support") Depends-on: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback for GPIO chips") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> --- drivers/pinctrl/intel/pinctrl-merrifield.c | 8 ++++++++ 1 file changed, 8 insertions(+)