Add support for the drive-strengh pin configuration using the generic
pinconf DT bindings.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
---
.../bindings/pinctrl/renesas,pfc-pinctrl.txt | 4 +-
drivers/pinctrl/sh-pfc/core.c | 15 +++
drivers/pinctrl/sh-pfc/core.h | 3 +
drivers/pinctrl/sh-pfc/pinctrl.c | 111 +++++++++++++++++++++
drivers/pinctrl/sh-pfc/sh_pfc.h | 17 ++++
5 files changed, 148 insertions(+), 2 deletions(-)
diff --git a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
index ffadb7a371f6..74e6ec0339d6 100644
--- a/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
+++ b/Documentation/devicetree/bindings/pinctrl/renesas,pfc-pinctrl.txt
@@ -72,8 +72,8 @@ Pin Configuration Node Properties:
The pin configuration parameters use the generic pinconf bindings defined in
pinctrl-bindings.txt in this directory. The supported parameters are
-bias-disable, bias-pull-up, bias-pull-down and power-source. For pins that
-have a configurable I/O voltage, the power-source value should be the
+bias-disable, bias-pull-up, bias-pull-down, drive strength and power-source. For
+pins that have a configurable I/O voltage, the power-source value should be the
nominal I/O voltage in millivolts.
diff --git a/drivers/pinctrl/sh-pfc/core.c b/drivers/pinctrl/sh-pfc/core.c
index 181ea98a63b7..73f0b33ee0a1 100644
--- a/drivers/pinctrl/sh-pfc/core.c
+++ b/drivers/pinctrl/sh-pfc/core.c
@@ -173,6 +173,21 @@ void sh_pfc_write_raw_reg(void __iomem *mapped_reg, unsigned int reg_width,
BUG();
}
+u32 sh_pfc_read_reg(struct sh_pfc *pfc, u32 reg, unsigned int width)
+{
+ return sh_pfc_read_raw_reg(sh_pfc_phys_to_virt(pfc, reg), width);
+}
+
+void sh_pfc_write_reg(struct sh_pfc *pfc, u32 reg, unsigned int width, u32 data)
+{
+ if (pfc->info->unlock_reg)
+ sh_pfc_write_raw_reg(
+ sh_pfc_phys_to_virt(pfc, pfc->info->unlock_reg), 32,
+ ~data);
+
+ sh_pfc_write_raw_reg(sh_pfc_phys_to_virt(pfc, reg), width, data);
+}
+
static void sh_pfc_config_reg_helper(struct sh_pfc *pfc,
const struct pinmux_cfg_reg *crp,
unsigned int in_pos,
diff --git a/drivers/pinctrl/sh-pfc/core.h b/drivers/pinctrl/sh-pfc/core.h
index 62f53b22ae85..fc05d0c516f3 100644
--- a/drivers/pinctrl/sh-pfc/core.h
+++ b/drivers/pinctrl/sh-pfc/core.h
@@ -62,6 +62,9 @@ int sh_pfc_unregister_pinctrl(struct sh_pfc *pfc);
u32 sh_pfc_read_raw_reg(void __iomem *mapped_reg, unsigned int reg_width);
void sh_pfc_write_raw_reg(void __iomem *mapped_reg, unsigned int reg_width,
u32 data);
+u32 sh_pfc_read_reg(struct sh_pfc *pfc, u32 reg, unsigned int width);
+void sh_pfc_write_reg(struct sh_pfc *pfc, u32 reg, unsigned int width,
+ u32 data);
int sh_pfc_get_pin_index(struct sh_pfc *pfc, unsigned int pin);
int sh_pfc_config_mux(struct sh_pfc *pfc, unsigned mark, int pinmux_type);
diff --git a/drivers/pinctrl/sh-pfc/pinctrl.c b/drivers/pinctrl/sh-pfc/pinctrl.c
index 87b0a599afaf..8efaa0631be6 100644
--- a/drivers/pinctrl/sh-pfc/pinctrl.c
+++ b/drivers/pinctrl/sh-pfc/pinctrl.c
@@ -476,6 +476,91 @@ static const struct pinmux_ops sh_pfc_pinmux_ops = {
.gpio_set_direction = sh_pfc_gpio_set_direction,
};
+static u32 sh_pfc_pinconf_find_drive_strength_reg(struct sh_pfc *pfc,
+ unsigned int pin, unsigned int *offset, unsigned int *size)
+{
+ const struct pinmux_drive_reg_field *field;
+ const struct pinmux_drive_reg *reg;
+ unsigned int i;
+
+ for (reg = pfc->info->drive_regs; reg->reg; ++reg) {
+ for (i = 0; i < ARRAY_SIZE(reg->fields); ++i) {
+ field = ®->fields[i];
+
+ if (field->size && field->pin == pin) {
+ *offset = field->offset;
+ *size = field->size;
+
+ return reg->reg;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static int sh_pfc_pinconf_get_drive_strength(struct sh_pfc *pfc,
+ unsigned int pin)
+{
+ unsigned long flags;
+ unsigned int offset;
+ unsigned int size;
+ u32 reg;
+ u32 val;
+
+ reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset, &size);
+ if (!reg)
+ return -EINVAL;
+
+ spin_lock_irqsave(&pfc->lock, flags);
+ val = sh_pfc_read_reg(pfc, reg, 32);
+ spin_unlock_irqrestore(&pfc->lock, flags);
+
+ val = (val >> offset) & GENMASK(size - 1, 0);
+
+ /* Convert the value to mA based on a full drive strength value of 24mA.
+ * We can make the full value configurable later if needed.
+ */
+ return (val + 1) * (size == 2 ? 6 : 3);
+}
+
+static int sh_pfc_pinconf_set_drive_strength(struct sh_pfc *pfc,
+ unsigned int pin, u16 strength)
+{
+ unsigned long flags;
+ unsigned int offset;
+ unsigned int size;
+ unsigned int step;
+ u32 reg;
+ u32 val;
+
+ reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset, &size);
+ if (!reg)
+ return -EINVAL;
+
+ step = size == 2 ? 6 : 3;
+
+ if (strength < step || strength > 24)
+ return -EINVAL;
+
+ /* Convert the value from mA based on a full drive strength value of
+ * 24mA. We can make the full value configurable later if needed.
+ */
+ strength = strength / step - 1;
+
+ spin_lock_irqsave(&pfc->lock, flags);
+
+ val = sh_pfc_read_reg(pfc, reg, 32);
+ val &= ~GENMASK(offset + size - 1, offset);
+ val |= strength << offset;
+
+ sh_pfc_write_reg(pfc, reg, 32, val);
+
+ spin_unlock_irqrestore(&pfc->lock, flags);
+
+ return 0;
+}
+
/* Check whether the requested parameter is supported for a pin. */
static bool sh_pfc_pinconf_validate(struct sh_pfc *pfc, unsigned int _pin,
enum pin_config_param param)
@@ -493,6 +578,9 @@ static bool sh_pfc_pinconf_validate(struct sh_pfc *pfc, unsigned int _pin,
case PIN_CONFIG_BIAS_PULL_DOWN:
return pin->configs & SH_PFC_PIN_CFG_PULL_DOWN;
+ case PIN_CONFIG_DRIVE_STRENGTH:
+ return pin->configs & SH_PFC_PIN_CFG_DRIVE_STRENGTH;
+
case PIN_CONFIG_POWER_SOURCE:
return pin->configs & SH_PFC_PIN_CFG_IO_VOLTAGE;
@@ -532,6 +620,17 @@ static int sh_pfc_pinconf_get(struct pinctrl_dev *pctldev, unsigned _pin,
break;
}
+ case PIN_CONFIG_DRIVE_STRENGTH: {
+ int ret;
+
+ ret = sh_pfc_pinconf_get_drive_strength(pfc, _pin);
+ if (ret < 0)
+ return ret;
+
+ *config = ret;
+ break;
+ }
+
case PIN_CONFIG_POWER_SOURCE: {
int ret;
@@ -584,6 +683,18 @@ static int sh_pfc_pinconf_set(struct pinctrl_dev *pctldev, unsigned _pin,
break;
+ case PIN_CONFIG_DRIVE_STRENGTH: {
+ unsigned int arg =
+ pinconf_to_config_argument(configs[i]);
+ int ret;
+
+ ret = sh_pfc_pinconf_set_drive_strength(pfc, _pin, arg);
+ if (ret < 0)
+ return ret;
+
+ break;
+ }
+
case PIN_CONFIG_POWER_SOURCE: {
unsigned int arg =
pinconf_to_config_argument(configs[i]);
diff --git a/drivers/pinctrl/sh-pfc/sh_pfc.h b/drivers/pinctrl/sh-pfc/sh_pfc.h
index 2123ab49d6a5..8d548fb39229 100644
--- a/drivers/pinctrl/sh-pfc/sh_pfc.h
+++ b/drivers/pinctrl/sh-pfc/sh_pfc.h
@@ -28,6 +28,7 @@ enum {
#define SH_PFC_PIN_CFG_PULL_UP (1 << 2)
#define SH_PFC_PIN_CFG_PULL_DOWN (1 << 3)
#define SH_PFC_PIN_CFG_IO_VOLTAGE (1 << 4)
+#define SH_PFC_PIN_CFG_DRIVE_STRENGTH (1 << 5)
#define SH_PFC_PIN_CFG_NO_GPIO (1 << 31)
struct sh_pfc_pin {
@@ -110,6 +111,21 @@ struct pinmux_cfg_reg {
{ var_fw0, var_fwn, 0 }, \
.enum_ids = (const u16 [])
+struct pinmux_drive_reg_field {
+ u16 pin;
+ u8 offset;
+ u8 size;
+};
+
+struct pinmux_drive_reg {
+ u32 reg;
+ const struct pinmux_drive_reg_field fields[8];
+};
+
+#define PINMUX_DRIVE_REG(name, r) \
+ .reg = r, \
+ .fields =
+
struct pinmux_data_reg {
u32 reg;
u8 reg_width;
@@ -166,6 +182,7 @@ struct sh_pfc_soc_info {
#endif
const struct pinmux_cfg_reg *cfg_regs;
+ const struct pinmux_drive_reg *drive_regs;
const struct pinmux_data_reg *data_regs;
const u16 *pinmux_data;
--
2.7.3
