From 03a61f11c00213394e3c7ac62ae416d034dc728f Mon Sep 17 00:00:00 2001
From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Date: Wed, 11 Nov 2020 14:06:05 +0200
Subject: [PATCH] pinctrl: merrifield: Set default bias in case no particular value given
Git-commit: 03a61f11c00213394e3c7ac62ae416d034dc728f
Patch-mainline: v5.10
References: git-fixes
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>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/pinctrl/intel/pinctrl-merrifield.c | 8 ++++++++
1 file changed, 8 insertions(+)
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;
--
2.26.2