pinctrl: SPEAr: Add SoC specific gpio configuration routines

Different SPEAr SoCs have different approach to configure pins as gpios. Some
configure a group of gpios with single register bit and others have one bit per
gpio pin. Only earlier one is implemented till now, this patch adds support for
later one.

Here we add callbacks to SoC specific code to configure gpios in
gpio_request_enable(). That will do additional SoC specific configuration to
enable gpio pins.

We also implement this callback for SPEAr1340 in this patch.

Signed-off-by: Shiraz Hashim <shiraz.hashim@st.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 27 insertions, 0 deletions

diff --git a/drivers/pinctrl/spear/pinctrl-spear1340.c b/drivers/pinctrl/spear/pinctrl-spear1340.c
index 0606b8cf3f2c..0b4af0e5cdc1 100644
--- a/drivers/pinctrl/spear/pinctrl-spear1340.c
+++ b/drivers/pinctrl/spear/pinctrl-spear1340.c
@@ -1971,6 +1971,32 @@ static struct spear_function *spear1340_functions[] = {
 	&sata_function,
 };
 
+static void gpio_request_endisable(struct spear_pmx *pmx, int pin,
+		bool enable)
+{
+	unsigned int regoffset, regindex, bitoffset;
+	unsigned int val;
+
+	/* pin++ as gpio configuration starts from 2nd bit of base register */
+	pin++;
+
+	regindex = pin / 32;
+	bitoffset = pin % 32;
+
+	if (regindex <= 3)
+		regoffset = PAD_FUNCTION_EN_1 + regindex * sizeof(int *);
+	else
+		regoffset = PAD_FUNCTION_EN_5 + (regindex - 4) * sizeof(int *);
+
+	val = pmx_readl(pmx, regoffset);
+	if (enable)
+		val &= ~(0x1 << bitoffset);
+	else
+		val |= 0x1 << bitoffset;
+
+	pmx_writel(pmx, val, regoffset);
+}
+
 static struct spear_pinctrl_machdata spear1340_machdata = {
 	.pins = spear1340_pins,
 	.npins = ARRAY_SIZE(spear1340_pins),
@@ -1978,6 +2004,7 @@ static struct spear_pinctrl_machdata spear1340_machdata = {
 	.ngroups = ARRAY_SIZE(spear1340_pingroups),
 	.functions = spear1340_functions,
 	.nfunctions = ARRAY_SIZE(spear1340_functions),
+	.gpio_request_endisable = gpio_request_endisable,
 	.modes_supported = false,
 };