[PATCH 0/2] r8a7795 pinctrl: Add drive strength support

[PATCH 0/2] r8a7795 pinctrl: Add drive strength support

[Laurent Pinchart]

Hello,

This patch series adds drive strength control support to the sh-pfc driver for
the R8A7795 (R-Car H3) SoC.

The SoC can control the drive strength of all GPIO pins, as well as of some
dedicated-purpose pins. As the R8A7795 pinctrl driver doesn't support non-GPIO
pins yet, this series is limited to controlling the drive strength on the GPIO
pins.

Patch 1/2 adds drive strength support to the sh-pfc driver. It hardcodes a few
assumptions that might be specific to the R8A7795, I'll revisit them if future
SoCs break them.

Patch 2/2 adds R8A7795-specific support by setting the drive strength
configuration flag for all GPIO pins, and defining the drive strength
registers layout.

The series has been tested on the Salvator-X board with the GPIO pins
connected to the on-board LEDs. The 4.7µF capacitor to ground provides a large
enough load on the lines to make the effect of the drive strength easily
measurable with an oscilloscope.

Laurent Pinchart (2):
  pinctrl: sh-pfc: Add drive strength support
  pinctrl: sh-pfc: r8a7795: Add drive strength support

 .../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/pfc-r8a7795.c               | 218 ++++++++++++++++++++-
 drivers/pinctrl/sh-pfc/pinctrl.c                   | 112 +++++++++++
 drivers/pinctrl/sh-pfc/sh_pfc.h                    |  17 ++
 6 files changed, 359 insertions(+), 10 deletions(-)

-- 
Regards,

Laurent Pinchart

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[PATCH 1/2] pinctrl: sh-pfc: Add drive strength support

[Laurent Pinchart]

Add support for the drive-strengh pin configuration using the generic
pinconf DT bindings.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
 .../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                   | 112 +++++++++++++++++++++
 drivers/pinctrl/sh-pfc/sh_pfc.h                    |  17 ++++
 5 files changed, 149 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..7aeb816ad946 100644
--- a/drivers/pinctrl/sh-pfc/pinctrl.c
+++ b/drivers/pinctrl/sh-pfc/pinctrl.c
@@ -476,6 +476,92 @@ 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 = &reg->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.
+	 */
+	if (size == 2)
+		val <<= 1;
+	return (val + 1) * 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;
+	u32 reg;
+	u32 val;
+
+	if (strength < 3 || strength > 24)
+		return -EINVAL;
+
+	reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset, &size);
+	if (!reg)
+		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 / 3 - 1;
+	if (size == 2)
+		strength >>= 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 +579,9 @@ 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 +621,17 @@ 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 +684,18 @@ 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

[PATCH 2/2] pinctrl: sh-pfc: r8a7795: Add drive strength support

[Laurent Pinchart]

Define the drive strength registers for the R8A7795. As the PFC driver
for the SoC only defines GPIO pins at the moment, limit drive strength
support to those pins. Pins without GPIO capabilities will be supported
later.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
---
 drivers/pinctrl/sh-pfc/pfc-r8a7795.c | 218 +++++++++++++++++++++++++++++++++--
 1 file changed, 210 insertions(+), 8 deletions(-)

diff --git a/drivers/pinctrl/sh-pfc/pfc-r8a7795.c b/drivers/pinctrl/sh-pfc/pfc-r8a7795.c
index ce4f5cdb0579..1cc0c1bea692 100644
--- a/drivers/pinctrl/sh-pfc/pfc-r8a7795.c
+++ b/drivers/pinctrl/sh-pfc/pfc-r8a7795.c
@@ -14,14 +14,14 @@
 #include "sh_pfc.h"
 
 #define CPU_ALL_PORT(fn, sfx)						\
-	PORT_GP_16(0, fn, sfx),						\
-	PORT_GP_28(1, fn, sfx),						\
-	PORT_GP_15(2, fn, sfx),						\
-	PORT_GP_16(3, fn, sfx),						\
-	PORT_GP_18(4, fn, sfx),						\
-	PORT_GP_26(5, fn, sfx),						\
-	PORT_GP_32(6, fn, sfx),						\
-	PORT_GP_4(7, fn, sfx)
+	PORT_GP_CFG_16(0, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_28(1, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_15(2, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_16(3, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_18(4, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_26(5, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_32(6, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH),	\
+	PORT_GP_CFG_4(7, fn, sfx, SH_PFC_PIN_CFG_DRIVE_STRENGTH)
 /*
  * F_() : just information
  * FM() : macro for FN_xxx / xxx_MARK
@@ -4219,6 +4219,207 @@ static const struct pinmux_cfg_reg pinmux_config_regs[] = {
 	{ },
 };
 
+static const struct pinmux_drive_reg pinmux_drive_regs[] = {
+	{ PINMUX_DRIVE_REG("DRVCTRL3", 0xe606030c) {
+		{ RCAR_GP_PIN(2,  9),  8, 3 },	/* AVB_MDC */
+		{ RCAR_GP_PIN(2, 10),  4, 3 },	/* AVB_MAGIC */
+		{ RCAR_GP_PIN(2, 11),  0, 3 },	/* AVB_PHY_INT */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL4", 0xe6060310) {
+		{ RCAR_GP_PIN(2, 12), 28, 3 },	/* AVB_LINK */
+		{ RCAR_GP_PIN(2, 13), 24, 3 },	/* AVB_AVTP_MATCH */
+		{ RCAR_GP_PIN(2, 14), 20, 3 },	/* AVB_AVTP_CAPTURE */
+		{ RCAR_GP_PIN(2,  0), 16, 3 },	/* IRQ0 */
+		{ RCAR_GP_PIN(2,  1), 12, 3 },	/* IRQ1 */
+		{ RCAR_GP_PIN(2,  2),  8, 3 },	/* IRQ2 */
+		{ RCAR_GP_PIN(2,  3),  4, 3 },	/* IRQ3 */
+		{ RCAR_GP_PIN(2,  4),  0, 3 },	/* IRQ4 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL5", 0xe6060314) {
+		{ RCAR_GP_PIN(2,  5), 28, 3 },	/* IRQ5 */
+		{ RCAR_GP_PIN(2,  6), 24, 3 },	/* PWM0 */
+		{ RCAR_GP_PIN(2,  7), 20, 3 },	/* PWM1 */
+		{ RCAR_GP_PIN(2,  8), 16, 3 },	/* PWM2 */
+		{ RCAR_GP_PIN(1,  0), 12, 3 },	/* A0 */
+		{ RCAR_GP_PIN(1,  1),  8, 3 },	/* A1 */
+		{ RCAR_GP_PIN(1,  2),  4, 3 },	/* A2 */
+		{ RCAR_GP_PIN(1,  3),  0, 3 },	/* A3 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL6", 0xe6060318) {
+		{ RCAR_GP_PIN(1,  4), 28, 3 },	/* A4 */
+		{ RCAR_GP_PIN(1,  5), 24, 3 },	/* A5 */
+		{ RCAR_GP_PIN(1,  6), 20, 3 },	/* A6 */
+		{ RCAR_GP_PIN(1,  7), 16, 3 },	/* A7 */
+		{ RCAR_GP_PIN(1,  8), 12, 3 },	/* A8 */
+		{ RCAR_GP_PIN(1,  9),  8, 3 },	/* A9 */
+		{ RCAR_GP_PIN(1, 10),  4, 3 },	/* A10 */
+		{ RCAR_GP_PIN(1, 11),  0, 3 },	/* A11 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL7", 0xe606031c) {
+		{ RCAR_GP_PIN(1, 12), 28, 3 },	/* A12 */
+		{ RCAR_GP_PIN(1, 13), 24, 3 },	/* A13 */
+		{ RCAR_GP_PIN(1, 14), 20, 3 },	/* A14 */
+		{ RCAR_GP_PIN(1, 15), 16, 3 },	/* A15 */
+		{ RCAR_GP_PIN(1, 16), 12, 3 },	/* A16 */
+		{ RCAR_GP_PIN(1, 17),  8, 3 },	/* A17 */
+		{ RCAR_GP_PIN(1, 18),  4, 3 },	/* A18 */
+		{ RCAR_GP_PIN(1, 19),  0, 3 },	/* A19 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL8", 0xe6060320) {
+		{ RCAR_GP_PIN(1, 20), 24, 3 },	/* CS0 */
+		{ RCAR_GP_PIN(1, 21), 20, 3 },	/* CS1_A26 */
+		{ RCAR_GP_PIN(1, 22), 16, 3 },	/* BS */
+		{ RCAR_GP_PIN(1, 23), 12, 3 },	/* RD */
+		{ RCAR_GP_PIN(1, 24),  8, 3 },	/* RD_WR */
+		{ RCAR_GP_PIN(1, 25),  4, 3 },	/* WE0 */
+		{ RCAR_GP_PIN(1, 26),  0, 3 },	/* WE1 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL9", 0xe6060324) {
+		{ RCAR_GP_PIN(1, 27), 28, 3 },	/* EX_WAIT0 */
+		{ RCAR_GP_PIN(0,  0), 20, 3 },	/* D0 */
+		{ RCAR_GP_PIN(0,  1), 16, 3 },	/* D1 */
+		{ RCAR_GP_PIN(0,  2), 12, 3 },	/* D2 */
+		{ RCAR_GP_PIN(0,  3),  8, 3 },	/* D3 */
+		{ RCAR_GP_PIN(0,  4),  4, 3 },	/* D4 */
+		{ RCAR_GP_PIN(0,  5),  0, 3 },	/* D5 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL10", 0xe6060328) {
+		{ RCAR_GP_PIN(0,  6), 28, 3 },	/* D6 */
+		{ RCAR_GP_PIN(0,  7), 24, 3 },	/* D7 */
+		{ RCAR_GP_PIN(0,  8), 20, 3 },	/* D8 */
+		{ RCAR_GP_PIN(0,  9), 16, 3 },	/* D9 */
+		{ RCAR_GP_PIN(0, 10), 12, 3 },	/* D10 */
+		{ RCAR_GP_PIN(0, 11),  8, 3 },	/* D11 */
+		{ RCAR_GP_PIN(0, 12),  4, 3 },	/* D12 */
+		{ RCAR_GP_PIN(0, 13),  0, 3 },	/* D13 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL11", 0xe606032c) {
+		{ RCAR_GP_PIN(0, 14), 28, 3 },	/* D14 */
+		{ RCAR_GP_PIN(0, 15), 24, 3 },	/* D15 */
+		{ RCAR_GP_PIN(7,  0), 20, 3 },	/* AVS1 */
+		{ RCAR_GP_PIN(7,  1), 16, 3 },	/* AVS2 */
+		{ RCAR_GP_PIN(7,  2), 12, 3 },	/* HDMI0_CEC */
+		{ RCAR_GP_PIN(7,  3),  8, 3 },	/* HDMI1_CEC */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL13", 0xe6060334) {
+		{ RCAR_GP_PIN(3,  0), 20, 3 },	/* SD0_CLK */
+		{ RCAR_GP_PIN(3,  1), 16, 3 },	/* SD0_CMD */
+		{ RCAR_GP_PIN(3,  2), 12, 3 },	/* SD0_DAT0 */
+		{ RCAR_GP_PIN(3,  3),  8, 3 },	/* SD0_DAT1 */
+		{ RCAR_GP_PIN(3,  4),  4, 3 },	/* SD0_DAT2 */
+		{ RCAR_GP_PIN(3,  5),  0, 3 },	/* SD0_DAT3 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL14", 0xe6060338) {
+		{ RCAR_GP_PIN(3,  6), 28, 3 },	/* SD1_CLK */
+		{ RCAR_GP_PIN(3,  7), 24, 3 },	/* SD1_CMD */
+		{ RCAR_GP_PIN(3,  8), 20, 3 },	/* SD1_DAT0 */
+		{ RCAR_GP_PIN(3,  9), 16, 3 },	/* SD1_DAT1 */
+		{ RCAR_GP_PIN(3, 10), 12, 3 },	/* SD1_DAT2 */
+		{ RCAR_GP_PIN(3, 11),  8, 3 },	/* SD1_DAT3 */
+		{ RCAR_GP_PIN(4,  0),  4, 3 },	/* SD2_CLK */
+		{ RCAR_GP_PIN(4,  1),  0, 3 },	/* SD2_CMD */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL15", 0xe606033c) {
+		{ RCAR_GP_PIN(4,  2), 28, 3 },	/* SD2_DAT0 */
+		{ RCAR_GP_PIN(4,  3), 24, 3 },	/* SD2_DAT1 */
+		{ RCAR_GP_PIN(4,  4), 20, 3 },	/* SD2_DAT2 */
+		{ RCAR_GP_PIN(4,  5), 16, 3 },	/* SD2_DAT3 */
+		{ RCAR_GP_PIN(4,  6), 12, 3 },	/* SD2_DS */
+		{ RCAR_GP_PIN(4,  7),  8, 3 },	/* SD3_CLK */
+		{ RCAR_GP_PIN(4,  8),  4, 3 },	/* SD3_CMD */
+		{ RCAR_GP_PIN(4,  9),  0, 3 },	/* SD3_DAT0 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL16", 0xe6060340) {
+		{ RCAR_GP_PIN(4, 10), 28, 3 },	/* SD3_DAT1 */
+		{ RCAR_GP_PIN(4, 11), 24, 3 },	/* SD3_DAT2 */
+		{ RCAR_GP_PIN(4, 12), 20, 3 },	/* SD3_DAT3 */
+		{ RCAR_GP_PIN(4, 13), 16, 3 },	/* SD3_DAT4 */
+		{ RCAR_GP_PIN(4, 14), 12, 3 },	/* SD3_DAT5 */
+		{ RCAR_GP_PIN(4, 15),  8, 3 },	/* SD3_DAT6 */
+		{ RCAR_GP_PIN(4, 16),  4, 3 },	/* SD3_DAT7 */
+		{ RCAR_GP_PIN(4, 17),  0, 3 },	/* SD3_DS */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL17", 0xe6060344) {
+		{ RCAR_GP_PIN(3, 12), 28, 3 },	/* SD0_CD */
+		{ RCAR_GP_PIN(3, 13), 24, 3 },	/* SD0_WP */
+		{ RCAR_GP_PIN(3, 14), 20, 3 },	/* SD1_CD */
+		{ RCAR_GP_PIN(3, 15), 16, 3 },	/* SD1_WP */
+		{ RCAR_GP_PIN(5,  0), 12, 3 },	/* SCK0 */
+		{ RCAR_GP_PIN(5,  1),  8, 3 },	/* RX0 */
+		{ RCAR_GP_PIN(5,  2),  4, 3 },	/* TX0 */
+		{ RCAR_GP_PIN(5,  3),  0, 3 },	/* CTS0 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL18", 0xe6060348) {
+		{ RCAR_GP_PIN(5,  4), 28, 3 },	/* RTS0_TANS */
+		{ RCAR_GP_PIN(5,  5), 24, 3 },	/* RX1 */
+		{ RCAR_GP_PIN(5,  6), 20, 3 },	/* TX1 */
+		{ RCAR_GP_PIN(5,  7), 16, 3 },	/* CTS1 */
+		{ RCAR_GP_PIN(5,  8), 12, 3 },	/* RTS1_TANS */
+		{ RCAR_GP_PIN(5,  9),  8, 3 },	/* SCK2 */
+		{ RCAR_GP_PIN(5, 10),  4, 3 },	/* TX2 */
+		{ RCAR_GP_PIN(5, 11),  0, 3 },	/* RX2 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL19", 0xe606034c) {
+		{ RCAR_GP_PIN(5, 12), 28, 3 },	/* HSCK0 */
+		{ RCAR_GP_PIN(5, 13), 24, 3 },	/* HRX0 */
+		{ RCAR_GP_PIN(5, 14), 20, 3 },	/* HTX0 */
+		{ RCAR_GP_PIN(5, 15), 16, 3 },	/* HCTS0 */
+		{ RCAR_GP_PIN(5, 16), 12, 3 },	/* HRTS0 */
+		{ RCAR_GP_PIN(5, 17),  8, 3 },	/* MSIOF0_SCK */
+		{ RCAR_GP_PIN(5, 18),  4, 3 },	/* MSIOF0_SYNC */
+		{ RCAR_GP_PIN(5, 19),  0, 3 },	/* MSIOF0_SS1 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL20", 0xe6060350) {
+		{ RCAR_GP_PIN(5, 20), 28, 3 },	/* MSIOF0_TXD */
+		{ RCAR_GP_PIN(5, 21), 24, 3 },	/* MSIOF0_SS2 */
+		{ RCAR_GP_PIN(5, 22), 20, 3 },	/* MSIOF0_RXD */
+		{ RCAR_GP_PIN(5, 23), 16, 3 },	/* MLB_CLK */
+		{ RCAR_GP_PIN(5, 24), 12, 3 },	/* MLB_SIG */
+		{ RCAR_GP_PIN(5, 25),  8, 3 },	/* MLB_DAT */
+		{ RCAR_GP_PIN(6,  0),  0, 3 },	/* SSI_SCK01239 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL21", 0xe6060354) {
+		{ RCAR_GP_PIN(6,  1), 28, 3 },	/* SSI_WS01239 */
+		{ RCAR_GP_PIN(6,  2), 24, 3 },	/* SSI_SDATA0 */
+		{ RCAR_GP_PIN(6,  3), 20, 3 },	/* SSI_SDATA1 */
+		{ RCAR_GP_PIN(6,  4), 16, 3 },	/* SSI_SDATA2 */
+		{ RCAR_GP_PIN(6,  5), 12, 3 },	/* SSI_SCK34 */
+		{ RCAR_GP_PIN(6,  6),  8, 3 },	/* SSI_WS34 */
+		{ RCAR_GP_PIN(6,  7),  4, 3 },	/* SSI_SDATA3 */
+		{ RCAR_GP_PIN(6,  8),  0, 3 },	/* SSI_SCK4 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL22", 0xe6060358) {
+		{ RCAR_GP_PIN(6,  9), 28, 3 },	/* SSI_WS4 */
+		{ RCAR_GP_PIN(6, 10), 24, 3 },	/* SSI_SDATA4 */
+		{ RCAR_GP_PIN(6, 11), 20, 3 },	/* SSI_SCK5 */
+		{ RCAR_GP_PIN(6, 12), 16, 3 },	/* SSI_WS5 */
+		{ RCAR_GP_PIN(6, 13), 12, 3 },	/* SSI_SDATA5 */
+		{ RCAR_GP_PIN(6, 14),  8, 3 },	/* SSI_SCK6 */
+		{ RCAR_GP_PIN(6, 15),  4, 3 },	/* SSI_WS6 */
+		{ RCAR_GP_PIN(6, 16),  0, 3 },	/* SSI_SDATA6 */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL23", 0xe606035c) {
+		{ RCAR_GP_PIN(6, 17), 28, 3 },	/* SSI_SCK78 */
+		{ RCAR_GP_PIN(6, 18), 24, 3 },	/* SSI_WS78 */
+		{ RCAR_GP_PIN(6, 19), 20, 3 },	/* SSI_SDATA7 */
+		{ RCAR_GP_PIN(6, 20), 16, 3 },	/* SSI_SDATA8 */
+		{ RCAR_GP_PIN(6, 21), 12, 3 },	/* SSI_SDATA9 */
+		{ RCAR_GP_PIN(6, 22),  8, 3 },	/* AUDIO_CLKA */
+		{ RCAR_GP_PIN(6, 23),  4, 3 },	/* AUDIO_CLKB */
+		{ RCAR_GP_PIN(6, 24),  0, 3 },	/* USB0_PWEN */
+	} },
+	{ PINMUX_DRIVE_REG("DRVCTRL24", 0xe6060360) {
+		{ RCAR_GP_PIN(6, 25), 28, 3 },	/* USB0_OVC */
+		{ RCAR_GP_PIN(6, 26), 24, 3 },	/* USB1_PWEN */
+		{ RCAR_GP_PIN(6, 27), 20, 3 },	/* USB1_OVC */
+		{ RCAR_GP_PIN(6, 28), 16, 3 },	/* USB30_PWEN */
+		{ RCAR_GP_PIN(6, 29), 12, 3 },	/* USB30_OVC */
+		{ RCAR_GP_PIN(6, 30),  8, 3 },	/* USB31_PWEN */
+		{ RCAR_GP_PIN(6, 31),  4, 3 },	/* USB31_OVC */
+	} },
+	{ },
+};
+
 const struct sh_pfc_soc_info r8a7795_pinmux_info = {
 	.name = "r8a77950_pfc",
 	.unlock_reg = 0xe6060000, /* PMMR */
@@ -4233,6 +4434,7 @@ const struct sh_pfc_soc_info r8a7795_pinmux_info = {
 	.nr_functions = ARRAY_SIZE(pinmux_functions),
 
 	.cfg_regs = pinmux_config_regs,
+	.drive_regs = pinmux_drive_regs,
 
 	.pinmux_data = pinmux_data,
 	.pinmux_data_size = ARRAY_SIZE(pinmux_data),
-- 
2.7.3

Re: [PATCH 1/2] pinctrl: sh-pfc: Add drive strength support

[Geert Uytterhoeven]

Hi Laurent,

On Mon, Mar 21, 2016 at 12:33 AM, Laurent Pinchart
<laurent.pinchart+renesas@ideasonboard.com> wrote:
> Add support for the drive-strengh pin configuration using the generic
> pinconf DT bindings.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Thanks for your patch!

> 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);
> +}

I like these helpers. They may also be used by r8a7778_pinmux_[gs]et_bias()
and r8a7790_[gs]et_io_voltage().

However, writing to the pull-up registers on r8a7778 doesn't seem to require
writing to the unlock register first.

Should we prepare for that and add a bool parameter to sh_pfc_write_reg()?

> --- a/drivers/pinctrl/sh-pfc/pinctrl.c
> +++ b/drivers/pinctrl/sh-pfc/pinctrl.c

> +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.
> +        */
> +       if (size == 2)
> +               val <<= 1;

I would write "val *= 2" here, as you're doing arithmetic, and have a "* 3"
below anyway.

> +       return (val + 1) * 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;
> +       u32 reg;
> +       u32 val;
> +
> +       if (strength < 3 || strength > 24)
> +               return -EINVAL;
> +
> +       reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset, &size);
> +       if (!reg)
> +               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 / 3 - 1;
> +       if (size == 2)
> +               strength >>= 1;

Same here: "strength / = 2".

Apart from the above, everything else looks fine to me, thx!

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 2/2] pinctrl: sh-pfc: r8a7795: Add drive strength support

[Geert Uytterhoeven]

Hi Laurent,

On Mon, Mar 21, 2016 at 12:33 AM, Laurent Pinchart
<laurent.pinchart+renesas@ideasonboard.com> wrote:
> Define the drive strength registers for the R8A7795. As the PFC driver
> for the SoC only defines GPIO pins at the moment, limit drive strength
> support to those pins. Pins without GPIO capabilities will be supported
> later.
>
> Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>

Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

Re: [PATCH 1/2] pinctrl: sh-pfc: Add drive strength support

[Laurent Pinchart]

Hi Geert,

On Wednesday 23 Mar 2016 10:54:02 Geert Uytterhoeven wrote:
> On Mon, Mar 21, 2016 at 12:33 AM, Laurent Pinchart wrote:
> > Add support for the drive-strengh pin configuration using the generic
> > pinconf DT bindings.
> > 
> > Signed-off-by: Laurent Pinchart
> > <laurent.pinchart+renesas@ideasonboard.com>
> 
> Thanks for your patch!
> 
> > 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);
> > +}
> 
> I like these helpers. They may also be used by r8a7778_pinmux_[gs]et_bias()
> and r8a7790_[gs]et_io_voltage().
> 
> However, writing to the pull-up registers on r8a7778 doesn't seem to require
> writing to the unlock register first.
> 
> Should we prepare for that and add a bool parameter to sh_pfc_write_reg()?

I've thought about it, but given that we don't have an immediate issue with 
the r8a7778 implementation, I decided it would be better to wait until we have 
a couple more users for that API to decide how to implement it best.

> > --- a/drivers/pinctrl/sh-pfc/pinctrl.c
> > +++ b/drivers/pinctrl/sh-pfc/pinctrl.c
> > 
> > +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.
> > +        */
> > +       if (size == 2)
> > +               val <<= 1;
> 
> I would write "val *= 2" here, as you're doing arithmetic, and have a "* 3"
> below anyway.

It's actually not really arithmetics, but I realize the code doesn't work 
correctly as a 2-bits drive strength set to 3 will be converted to 21 instead 
of 34. I'll fix it and resubmit.

> > +       return (val + 1) * 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;
> > +       u32 reg;
> > +       u32 val;
> > +
> > +       if (strength < 3 || strength > 24)
> > +               return -EINVAL;
> > +
> > +       reg = sh_pfc_pinconf_find_drive_strength_reg(pfc, pin, &offset,
> > &size); +       if (!reg)
> > +               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 / 3 - 1;
> > +       if (size == 2)
> > +               strength >>= 1;
> 
> Same here: "strength / = 2".
> 
> Apart from the above, everything else looks fine to me, thx!
> 
> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>

-- 
Regards,

Laurent Pinchart